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Note: This page contains sample records for the topic "rectangular precast concrete" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


1

Technological rules and constraints affecting design of precast concrete housing  

E-Print Network (OSTI)

Precast concrete technology is of great importance in multifamily housing. This technology provides the possibility to the industrialize housing construction and thus enhance the availability and quality of houses. With ...

Nakamura, Takashi

1994-01-01T23:59:59.000Z

2

Characterization of Self-Consolidating Concrete for the Design of Precast, Pretensioned Bridge Superstructure Elements  

E-Print Network (OSTI)

Self-consolidating concrete (SCC) is a new, innovative construction material that can be placed into forms without the need for mechanical vibration. The mixture proportions are critical for producing quality SCC and require an optimized combination of coarse and fine aggregates, cement, water, and chemical and mineral admixtures. The required mixture constituents and proportions may affect the mechanical properties, bond characteristics, and long-term behavior, and SCC may not provide the same inservice performance as conventional concrete (CC). Different SCC mixture constituents and proportions were evaluated for mechanical properties, shear characteristics, bond characteristics, creep, and durability. Variables evaluated included mixture type (CC or SCC), coarse aggregate type (river gravel or limestone), and coarse aggregate volume. To correlate these results with full-scale samples and investigate structural behavior related to strand bond properties, four girder-deck systems, 40 ft (12 m) long, with CC and SCC pretensioned girders were fabricated and tested. Results from the research indicate that the American Association of State Highway Transportation Officials Load and Resistance Factor Design (AASHTO LRFD) Specifications can be used to estimate the mechanical properties of SCC for a concrete compressive strength range of 5 to 10 ksi (34 to 70 MPa). In addition, the research team developed prediction equations for concrete compressive strength ranges from 5 to 16 ksi (34 to 110 MPa). With respect to shear characteristics, a more appropriate expression is proposed to estimate the concrete shear strength for CC and SCC girders with a compressive strength greater than 10 ksi (70 MPa). The author found that girder-deck systems with Type A SCC girders exhibit similar flexural performance as deck-systems with CC girders. The AASHTO LRFD (2006) equations for computing the cracking moment, nominal moment, transfer length, development length, and prestress losses may be used for SCC girder-deck systems similar to those tested in this study. For environments exhibiting freeze-thaw cycles, a minimum 16-hour release strength of 7 ksi (48 MPa) is recommended for SCC mixtures.

Kim, Young Hoon

2008-12-01T23:59:59.000Z

3

Progressive collapse simulation of precast panel shear walls during earthquakes  

Science Conference Proceedings (OSTI)

A distinct element method (DEM) program is modified to model precast panel shear walls. The influence of collapse time t"0 of local failure of a panel is presented. Integrity analyses of a twelve-storey, three-bay precast panel shear wall in different ... Keywords: Concrete panels, Distinct element method, Earthquakes, Failure process simulation, Progressive collapse

O. A. Pekau; Yuzhu Cui

2006-01-01T23:59:59.000Z

4

Rectangular Reinforced Concrete Beams Strengthened with CFRP Straps  

E-Print Network (OSTI)

, the rate of softening increases (see Fig. 2(a)). The principal tensile strain at the crack plane slipping stage (??_????) corresponds to the intersection of the curves represented by Eqns. 1 and 2. Fig. 2(b) shows the behavior of ??_???? vs ? assuming ??... increases significantly, the crack planes start to slip, and the steel web reinforcement tends to yield. The aggregate interlocking mechanism and the concrete contribution towards the shear strength deteriorate [Yapa 2011]. If however the beam 2...

Yapa, Hiran D.; Lees, Janet M.

2013-07-13T23:59:59.000Z

5

Emerging Energy-efficiency and CO2 Emission-reduction Technologies for Cement and Concrete Production  

E-Print Network (OSTI)

A new process stores carbon dioxide in precast concrete.G. J. Venta. 2009. Carbon Dioxide Reduction Technologyuse of captured carbon dioxide. Available at http://

Hasanbeigi, Ali

2013-01-01T23:59:59.000Z

6

Designing Precast Concrete Cross Wall Joints Against Progressive Collapse  

E-Print Network (OSTI)

and parametric analysis will follow. Reference Department of Defense (2005). Unified Facilities Criteria (UFC-4-023-03

Birmingham, University of

7

Seismic Performance Assessment and Probabilistic Repair Cost Analysis of Precast Concrete Cladding Systems for Multistory Buildings  

E-Print Network (OSTI)

Costs (2009). The cost per square foot was determined fromcost for basement levels is given at $36.40 per square foot

Hunt, Jeffrey Patrick

2010-01-01T23:59:59.000Z

8

Seismic Performance Assessment and Probabilistic Repair Cost Analysis of Precast Concrete Cladding Systems for Multistory Buildings  

E-Print Network (OSTI)

221 Fig. 7.10 Glass fallout from window glazing system (1995a) Fig. 7.10 Glass fallout from window glazing system (before cracking and glass fallout occurs. The results of the

Hunt, Jeffrey Patrick

2010-01-01T23:59:59.000Z

9

Energy Efficiency Improvement and Cost Saving Oportunities for the Concrete Industry  

SciTech Connect

The U.S. concrete industry is the main consumer of U.S.-produced cement. The manufacturing of ready mixed concrete accounts for more than 75% of the U.S. concrete production following the manufacturing of precast concrete and masonry units. The most significant expenditure is the cost of materials accounting for more than 50% of total concrete production costs - cement only accounts for nearly 24%. In 2009, energy costs of the U.S. concrete industry were over $610 million. Hence, energy efficiency improvements along with efficient use of materials without negatively affecting product quality and yield, especially in times of increased fuel and material costs, can significantly reduce production costs and increase competitiveness. The Energy Guide starts with an overview of the U.S. concrete industrys structure and energy use, a description of the various manufacturing processes, and identification of the major energy consuming areas in the different industry segments. This is followed by a description of general and process related energy- and cost-efficiency measures applicable to the concrete industry. Specific energy and cost savings and a typical payback period are included based on literature and case studies, when available. The Energy Guide intends to provide information on cost reduction opportunities to energy and plant managers in the U.S. concrete industry. Every cost saving opportunity should be assessed carefully prior to implementation in individual plants, as the economics and the potential energy and material savings may differ.

Kermeli, Katerina; Worrell, Ernst; Masanet, Eric

2011-12-01T23:59:59.000Z

10

Concrete Electrical Conductivity Test  

Science Conference Proceedings (OSTI)

Concrete Electrical Conductivity Test. Description/Summary: ... Details. Type of software: Virtual concrete electrical conductivity test. Authors: ...

2013-06-11T23:59:59.000Z

11

Concrete concentrator panel development program for SolarOil project, Phase I  

DOE Green Energy (OSTI)

The results of the General Atomic (GA) fixed-mirror solar concentrator (FMSC) concrete panel development program are presented. The FMSC is part of the solar steam supply system proposed by GA for the SolarOil project. The program was conducted to determine the achievable accuracy of precast concrete concentrator panels and to investigate expedient and economical mass production of the panels. One steel form, two concrete forms, and three concrete panels were fabricated and about 1500 slat angle measurements made using a laser inspection fixture developed expressly for this purpose. All panels were 1.83 m (6 ft) long and had a 3.6 m (11 ft 10 in.) aperture and 71 slats. Proper concrete mixes, parting compounds, placement methods, vibrating techniques, and curing procedures were identified, and the hardware and techniques for stripping and turning the panels were tested. Based upon test results and structural calculations it was concluded that reasonably priced 5.5-m (18 ft) long panels can be produced with either steel or fiberglass-coated concrete forms with 95% to 99% of the slat area within +-0.25/sup 0/ of the desired angles. With steam curing, the production rate is one panel every other working day per 5.5 m (18 ft) of form length.

Nicolayeff, V.; Chow, G.S.; Koploy, M.

1980-05-01T23:59:59.000Z

12

Concrete Decks  

E-Print Network (OSTI)

Federal Highway Administration (FHWA), several crashworthy wood bridge railings and approach railing transitions have been adapted for use on concrete bridge decks. These railings meet testing and evaluation criteria outlined in National Cooperative Research Program (NCHRP) Report 350, Recommended Procedures for the Safety Performance Evaluation of Highway Features, and include a glued-laminated timber (glulam) rail, with and without a curb, at Test Level- 2 (TL-2), a glulam rail with curb at TL-4, and a glulam curb rail for low-volume roads at TL-1. In adapting the railings from a wood deck to a concrete deck, the critical consideration was railing attachment to the deck. A comparable connection was obtained by an analysis of maximum loads measured by field instrumentation during crash testing or by equating the ultimate capacity of connections used on the wood deck to those required for a concrete deck. For the convenience of the user, full drawing sets are provided in customary U.S. and S.I. units.

United States; Forest Service; Wood Bridge Railings For; Michael A. Ritter; Ronald K. Faller; Paula D. Hilbrich Lee; Barry T. Rosson; Sheila Rimal; Duwadi Abstract

1998-01-01T23:59:59.000Z

13

Propagation in LHM slab loaded rectangular waveguide  

Science Conference Proceedings (OSTI)

The strange properties of Left - Handed Materials (LHM), whose permittivity and permeability are both negative, is briefly introduced. The electric- and magnetic-field components are given in rectangular waveguide loaded with LHM by use of field component ... Keywords: cutoff wavelength, dispersion equation, group velocity, left-handed materials, rectangular waveguide

Rui-Lian Li

2011-09-01T23:59:59.000Z

14

HIGH DENSITY SLAG CONCRETE  

SciTech Connect

Test results are presented that show that a strong concrete weighing approximately 185 lb/ft/sup 3/ can be made using water, waste lead slag, and Ciment Fondu. Feasibility, materials, mortar tests, concrete tests, and Ciment Fondu concretes are discussed. A 24-in.-thick concrete shield wall would have to be increased in thickness by 5 in. if slag concrete is used in place of barytes or magnetite concrete. On a pound-for-pound basis, the waste lead slag concrete materials were 30% cheaper than barytes and magnetite concrete materials. (M.C.G.)

Northup, T.E.

1963-08-01T23:59:59.000Z

15

Insulating polymer concrete  

DOE Patents (OSTI)

A lightweight insulating polymer concrete formed from a lightweight closed cell aggregate and a water resistance polymeric binder.

Schorr, H. Peter (Douglaston, NY); Fontana, Jack J. (Shirley, NY); Steinberg, Meyer (Melville, NY)

1987-01-01T23:59:59.000Z

16

The development of an alternate building system based on the use of an existing standardized component : precast, prestressed, hollow-core concrete slab  

E-Print Network (OSTI)

The primary scope of this thesis is a conceptual design implementation for a new building systems approach. This system is based on a standardized, economically feasible and widely used prefabricated structural component. ...

Simovic, Laszlo

1984-01-01T23:59:59.000Z

17

Rule-based Mamdani-type fuzzy modelling of thermal performance of multi-layer precast concrete panels used in residential buildings in Turkey  

Science Conference Proceedings (OSTI)

Heat insulation applied on outer wall surfaces of buildings for the purpose of conserving energy, can be analyzed experimentally, mathematically and by using simulation modelling. In this study, simulation modelling of insulation layer (d"2), for residential ... Keywords: Insulation, Prefabricated panel, Rule-based Mamdani-type fuzzy modelling, Thermal analysis

M. Tosun; K. Dincer; S. Baskaya

2011-05-01T23:59:59.000Z

18

Hotter Cements, Cooler Concretes  

Science Conference Proceedings (OSTI)

... 7: Measured concrete temperatures for Texas highway mass ... refer to the east and West sides of ... Through the use of an intermediate size lightweight ...

19

Segmentally Constructed Prestressed Concrete  

E-Print Network (OSTI)

Segmentally Constructed Prestressed Concrete Hyperboloid Cooling Tower Saml H. Rizkalla Assistant large capacity power plant facilities, the natural draft cooling tower in the fonn of a thin shell concrete natural draft cooling towers is expensive and time-consuming. The cost of the structure

20

Concrete sample point: 304 Concretion Facility  

SciTech Connect

This report contains information concerning the analysis of concretes for volatile organic compounds. Included are the raw data for these analysis and the quality control data, the standards data, and all of the accompanying chains-of-custody records and requests for special analysis.

Rollison, M.D.

1995-03-10T23:59:59.000Z

Note: This page contains sample records for the topic "rectangular precast concrete" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Electrokinetic decontamination of concrete  

Science Conference Proceedings (OSTI)

ELECTROSORB Electrokinetic Extraction Technology, developed by ISOTRON Corp., offers a cost-effective approach to treating contaminated concrete. Heavy metals/radionuclides trapped in concrete can be extracted using this process if they are chemically solubilized; solubilizers used are citric acid alone and a mixture of citric and nitric acids. A DC electric field is applied across the contaminated concrete to electrokinetically transport the solubilized contaminants from the concrete pores to a collector on the concrete surface. The collector is an extraction pad laid on the surface. The pad provides confinement for a planar electrode and solubilizer solution; it is operated under a vacuum to hold the pad against the concrete surface. Operation requires little attendance, reducing the workers` health hazards. The process incorporates a mechanism for recycling the solubilizer solution. A field demonstration of the process took place in Building 21 of DOE`s Mound facility in Miamisburg, OH, over 12 days in June 1996. The thorium species present in this building`s concrete floors included ThO{sub 2} and thorium oxalate. The nitric acid was found to facilitate Th extraction.

Lomasney, H.L.; SenGupta, A.K.; Yachmenev, V.

1996-12-31T23:59:59.000Z

22

Rotating Heat Transfer in High Aspect Ratio Rectangular Cooling...  

NLE Websites -- All DOE Office Websites (Extended Search)

Reynolds Number (Nu Nu o ) (f f o ) 24% Increase in Cooling Performance Rotating Heat Transfer in High Aspect Ratio Rectangular Cooling Passages with Shaped Turbulators...

23

Structural Materials: 95. Concrete  

SciTech Connect

Nuclear power plant concrete structures and their materials of construction are described, and their operating experience noted. Aging and environmental factors that can affect the durability of the concrete structures are identified. Basic components of a program to manage aging of these structures are identified and described. Application of structural reliability theory to devise uniform risk-based criteria by which existing facilities can be evaluated to achieve a desired performance level when subjected to uncertain demands and to quantify the effects of degradation is outlined. Finally, several areas are identified where additional research is desired.

Naus, Dan J [ORNL

2012-01-01T23:59:59.000Z

24

High temperature polymer concrete  

DOE Patents (OSTI)

This invention is concerned with a polymer concrete composition, which is a two-component composition useful with many bases including metal. Component A, the aggregate composition, is broadly composed of silica, silica flour, portland cement, and acrylamide, whereas Component B, which is primarily vinyl and acrylyl reactive monomers, is a liquid system.

Fontana, J.J.; Reams, W.

1984-05-29T23:59:59.000Z

25

A hybrid heuristic algorithm for the rectangular packing problem  

Science Conference Proceedings (OSTI)

A hybrid heuristic algorithm for the two-dimensional rectangular packing problem is presented. This algorithm is mainly based on divide-and-conquer and greedy strategies. The computational results on a class of benchmark problems have shown that the ...

Defu Zhang; Ansheng Deng; Yan Kang

2005-05-01T23:59:59.000Z

26

Research Required to Support Full Implementation of ...  

Science Conference Proceedings (OSTI)

... Precast concrete cladding Heating, ventilating, and air conditioning systems Fixed windows Skylights over large atria Glass fiber reinforced ...

2009-05-05T23:59:59.000Z

27

Hydraulic properties of asphalt concrete.  

E-Print Network (OSTI)

??This research has applied standard unsaturated flow models and laboratory methods common to soil analysis, to characterize the hydraulic properties of asphalt concrete. Wetting and (more)

Pease, Ronald Eric

2010-01-01T23:59:59.000Z

28

Learning from Roman Seawater Concrete  

NLE Websites -- All DOE Office Websites (Extended Search)

The ancient Romans, however, made concrete by mixing lime and volcanic rock. For underwater structures, lime and volcanic ash were mixed to form mortar, and this mortar and...

29

Computational Materials Science of Concrete  

Science Conference Proceedings (OSTI)

... However, the problem of amorphous semiconductors, or of glass, was entirely ... in the concrete field: the US National Stone Sand and Gravel ...

2012-07-02T23:59:59.000Z

30

Energy Balances of Curing Concrete Bridge Decks  

Science Conference Proceedings (OSTI)

Atmospheric conditions for several days after concrete is poured influence the exothermic, temperature-dependent, hydration reactions of concrete's cementitious (binding) components. Because excessively high concrete temperatures or lack of water ...

Gary S. Wojcik; David R. Fitzjarrald

2001-11-01T23:59:59.000Z

31

Accelerated and Natural Carbonation of Concretes with ...  

Science Conference Proceedings (OSTI)

... many parts of the world, corrosion of reinforcing steel in concrete induced by carbonation of the concrete continues to be a major durability concern. ...

2013-09-05T23:59:59.000Z

32

The Virtual Cement and Concrete Testing Laboratory ...  

Science Conference Proceedings (OSTI)

... Mitigation of early age cracking in high volume fly ash concrete Mitigation of early age-cracking in high volume fly ash concrete ...

2010-11-12T23:59:59.000Z

33

Nuclear Power Plant Concrete Structures  

Science Conference Proceedings (OSTI)

A nuclear power plant (NPP) involves complex engineering structures that are significant items of the structures, systems and components (SSC) important to the safe and reliable operation of the NPP. Concrete is the commonly used civil engineering construction material in the nuclear industry because of a number of advantageous properties. The NPP concrete structures underwent a great degree of evolution, since the commissioning of first NPP in early 1960. The increasing concern with time related to safety of the public and environment, and degradation of concrete structures due to ageing related phenomena are the driving forces for such evolution. The concrete technology underwent rapid development with the advent of chemical admixtures of plasticizer/super plasticizer category as well as viscosity modifiers and mineral admixtures like fly ash and silica fume. Application of high performance concrete (HPC) developed with chemical and mineral admixtures has been witnessed in the construction of NPP structures. Along with the beneficial effect, the use of admixtures in concrete has posed a number of challenges as well in design and construction. This along with the prospect of continuing operation beyond design life, especially after 60 years, the impact of extreme natural events ( as in the case of Fukushima NPP accident) and human induced events (e.g. commercial aircraft crash like the event of September 11th 2001) has led to further development in the area of NPP concrete structures. The present paper aims at providing an account of evolution of NPP concrete structures in last two decades by summarizing the development in the areas of concrete technology, design methodology and construction techniques, maintenance and ageing management of concrete structures.

Basu, Prabir [International Atomic Energy Agency (IAEA)] [International Atomic Energy Agency (IAEA); Labbe, Pierre [Electricity of France (EDF)] [Electricity of France (EDF); Naus, Dan [Oak Ridge National Laboratory (ORNL)] [Oak Ridge National Laboratory (ORNL)

2013-01-01T23:59:59.000Z

34

Explosive demolition of activated concrete  

SciTech Connect

This paper describes the removal of a radiologically contaminated concrete pad. This pad was removed during 1979 by operating personnel under the direction of the Waste Management Program of EG and G Idaho, Inc. The concrete pad was the foundation for the Organic Moderated Reactor Experiment (OMRE) reactor vessel located at the Idaho National Engineering Laboratory (INEL). The pad consisted of a cylindrical concrete slab 15 ft in diameter, 2 ft thick, and reinforced with steel bar. It was poured directly onto basalt rocks approximately 20 ft below grade. The entire pad contained induced radioactivity and was therefore demolished, boxed, and buried rather than being decontaminated. The pad was demolished by explosive blasting.

Smith, D.L.

1980-01-01T23:59:59.000Z

35

Evaluation of Contemporary Design of Reinforced Concrete ...  

Science Conference Proceedings (OSTI)

Page 1. Evaluation of Contemporary Design of Reinforced Concrete Lateral Resisting Systems Using Current Performance ...

2011-02-16T23:59:59.000Z

36

Testing of concrete by laser ablation  

DOE Patents (OSTI)

A method is disclosed for testing concrete in a structure in situ, by: directing a succession of pulses of laser radiation at a point on the structure so that each pulse effects removal of a quantity of concrete and transfers energy to the concrete; detecting a characteristic of energy which has been transferred to the concrete; determining, separately from the detecting step, the total quantity of concrete removed by the succession of pulses; and calculating a property of the concrete on the basis of the detected energy characteristic and the determined total quantity of concrete removed. 1 fig.

Flesher, D.J.; Becker, D.L.; Beem, W.L.; Berry, T.C.; Cannon, N.S.

1997-01-07T23:59:59.000Z

37

Testing of concrete by laser ablation  

DOE Patents (OSTI)

A method of testing concrete in a structure in situ, by: directing a succession of pulses of laser radiation at a point on the structure so that each pulse effects removal of a quantity of concrete and transfers energy to the concrete; detecting a characteristic of energy which has been transferred to the concrete; determining, separately from the detecting step, the total quantity of concrete removed by the succession of pulses; and calculating a property of the concrete on the basis of the detected energy characteristic and the determined total quantity of concrete removed.

Flesher, Dann J. (Benton City, WA); Becker, David L. (Kennewick, WA); Beem, William L. (Kennewick, WA); Berry, Tommy C. (Kennewick, WA); Cannon, N. Scott (Kennewick, WA)

1997-01-01T23:59:59.000Z

38

Corrosion resistance of concrete reinforcement  

E-Print Network (OSTI)

The objective of this thesis is to investigate the mechanism of corrosion of steel reinforcement in concrete and epoxy coated reinforcing bars as corrosion resistant alternatives. Several case studies explore the durability ...

Ward-Waller, Elizabeth, 1982-

2005-01-01T23:59:59.000Z

39

Keys, nominals, and concrete domains  

Science Conference Proceedings (OSTI)

Many description logics (DLs) combine knowledge representation on an abstract, logical level with an interface to "concrete" domains like numbers and strings with built-in predicates such as <, +, and prefix-of. These hybrid DLs have turned out to ...

Carsten Lutz; Carlos Areces; Ian Horrocks; Ulrike Sattler

2005-01-01T23:59:59.000Z

40

Electrically conductive polymer concrete coatings  

DOE Patents (OSTI)

A sprayable electrically conductive polymer concrete coating for vertical d overhead applications is described. The coating is permeable yet has low electrical resistivity (<10 ohm-cm), good bond strength to concrete substrates, and good weatherability. A preferred formulation contains about 60 wt % calcined coke breeze, 40 wt % vinyl ester with 3.5 wt % modified bentonite clay. Such formulations apply evenly and provide enough rigidity for vertical or overhead structures so there is no drip or sag.

Fontana, J.J.; Elling, D.; Reams, W.

1990-03-13T23:59:59.000Z

Note: This page contains sample records for the topic "rectangular precast concrete" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Electrically conductive polymer concrete coatings  

DOE Patents (OSTI)

A sprayable electrically conductive polymer concrete coating for vertical d overhead applications is described. The coating is permeable yet has low electrical resistivity (<10 ohm-cm), good bond strength to concrete substrates, and good weatherability. A preferred formulation contains about 60 wt % calcined coke breeze, 40 wt % vinyl ester with 3.5 wt % modified bentonite clay. Such formulations apply evenly and provide enough rigidity for vertical or overhead structures so there is no drip or sag.

Fontana, Jack J. (Shirley, NY); Elling, David (Centereach, NY); Reams, Walter (Shirley, NY)

1990-01-01T23:59:59.000Z

42

Electrically conductive polymer concrete coatings  

DOE Patents (OSTI)

A sprayable electrically conductive polymer concrete coating for vertical and overhead applications is described. The coating is permeable yet has low electrical resistivity (<10 ohm-cm), good bond strength to concrete substrates, and good weatherability. A preferred formulation contains about 60 wt% calcined coke breeze, 40 wt% vinyl ester resin with 3.5 wt% modified bentonite clay. Such formulations apply evenly and provide enough rigidity for vertical or overhead structures so there is no drip or sag. 4 tabs.

Fontana, J.J.; Elling, D.; Reams, W.

1988-05-26T23:59:59.000Z

43

Radial Eigenmodes for a Toroidal Waveguide with Rectangular Cross Section  

SciTech Connect

In applying mode expansion to solve the CSR impedance for a section of toroidal vacuum chamber with rectangular cross section, we identify the eigenvalue problem for the radial eigenmodes which is different from that for cylindrical structures. In this paper, we present the general expressions of the radial eigenmodes, and discuss the properties of the eigenvalues on the basis of the Sturm-Liouville theory.

Rui Li

2012-07-01T23:59:59.000Z

44

Rectangular-Mask Coronagraphs for High-Contrast Imaging  

E-Print Network (OSTI)

We present yet another new family of masks for high-contrast imaging as required for the to-be-built terrestrial planet finder space telescope. The ``best'' design involves a square entrance pupil having a 4-vane spider, a square image-plane mask containing a plus-sign shaped occulter to block the starlight inside 0.6 lambda/D, and a Lyot-plane mask consisting of a rectangular array of rectangular opennings. Using Fraunhofer analysis, we show that the optical system can image a planet 10^{-10} times as bright as an on-axis star in four rectangular regions given by {(xi,zeta): 1.4 stripes of opaque material with the stripes oriented at right angles to each other. We call these striped masks barcode masks. We show that it is sufficient for the barcode masks by themselves to provide 10^{-5} contrast. This then guarantees that the full system will provide the required 10^{-10} contrast.

Robert J. Vanderbei; N. Jeremy Kasdin; David N. Spergel

2004-01-30T23:59:59.000Z

45

Roller-Compacted Concrete for Dams  

Science Conference Proceedings (OSTI)

Placing mass concrete by the roller-compacted method improves the economics of hydroelectric dam construction. Many sites previously considered uneconomical for embankment or conventional concrete construction may now prove feasible.

1986-09-29T23:59:59.000Z

46

Advanced Nuclear Technology: Embedded Sensors in Concrete  

Science Conference Proceedings (OSTI)

One of the greatest hindrances to concrete inspection in nuclear power plants is the lack of accessibility to many concrete structures. This report aims to address the use of embedded sensors in future power plants to allow for inspection of inaccessible structures and to facilitate continuous monitoring of the critical concrete structures of the power plants. Monitoring these structures using embedded sensors is especially important because many large concrete structures in nuclear power plants are not ...

2011-11-30T23:59:59.000Z

47

Concrete Degradation Modeling in the Evaluation of ...  

Science Conference Proceedings (OSTI)

... as a Decommission Option by ... Page 2. Concrete Degradation Modeling in the Evaluation of Entombment as a Decommissioning Option ...

2004-07-26T23:59:59.000Z

48

Comparison of concrete rheometers: International tests at ...  

Science Conference Proceedings (OSTI)

... Parainen (Finland): Erik Nordenswan Advanced Concrete and Masonry Centre, Paisley ... this mixture was designed to minimize the wall effects and ...

2002-03-26T23:59:59.000Z

49

Corner heating in rectangular solid oxide electrochemical cell generators  

DOE Patents (OSTI)

Disclosed is an improvement in a solid oxide electrochemical cell generator 1 having a rectangular design with four sides that meet at corners, and containing multiplicity of electrically connected fuel cells 11, where a fuel gas is passed over one side of said cells and an oxygen containing gas is passed into said cells, and said fuel is burned to form heat, electricity, and an exhaust gas. The improvement comprises passing the exhaust gases over the multiplicity of cells 11 in such a way that more of the heat in said exhaust gases flows at the corners of the generator, such as through channels 19.

Reichner, Philip (Plum Boro, PA)

1989-01-01T23:59:59.000Z

50

Characteristics of multimode heat transfer in a differentially-heated horizontal rectangular duct.  

E-Print Network (OSTI)

??This study presents the numerical analysis of steady laminar flow heat transfer in a horizontal rectangular duct with differential heating on the vertical walls. Three (more)

Wangdhamkoom, Panitan

2007-01-01T23:59:59.000Z

51

DEVELOPING FLOW AND HEAT TRANSFER IN STRONGLY CURVED DUCTS OF RECTANGULAR CROSS-SECTION  

E-Print Network (OSTI)

Forced Convection Heat Transfer in Curved RectangularInfluence of Curvature on Heat Transfer to IncompressibleT. , "Forced Convective Heat Transfer in a Curved Channel

Yee, G.

2010-01-01T23:59:59.000Z

52

Concrete Decontamination Technology Workshop Proceedings  

Science Conference Proceedings (OSTI)

EPRI has initiated a series of highly focused workshops, each dealing with a specific nuclear power plant decommissioning technology. The objective is to equip utility personnel with the information needed to assess the use of these technologies in their individual projects. This report presents the results of the first workshop, which covered concrete decontamination.

1998-12-31T23:59:59.000Z

53

Diffusion of Radionuclides in Concrete and Soil  

SciTech Connect

One of the methods being considered for safely disposing of Category 3 low-level radioactive wastes is to encase the waste in concrete. Such concrete encasement would contain and isolate the waste packages from the hydrologic environment and would act as an intrusion barrier. Any failure of concrete encasement may result in water intrusion and consequent mobilization of radionuclides from the waste packages. The mobilized radionuclides may escape from the encased concrete by mass flow and/or diffusion and move into the surrounding subsurface environment. Therefore, it is necessary to assess the performance of the concrete encasement structure and the ability of the surrounding soil to retard radionuclide migration. The objective of our study was to measure the diffusivity of Re, Tc and I in concrete containment and the surrounding vadose zone soil. Effects of carbonation, presence of metallic iron, and fracturing of concrete and the varying moisture contents in soil on the diffusivities of Tc and I were evaluated.

Mattigod, Shas V.; Wellman, Dawn M.; Bovaird, Chase C.; Parker, Kent E.; Recknagle, Kurtis P.; Clayton, Libby N.; Wood, Marcus I.

2012-04-25T23:59:59.000Z

54

An approximate algorithm for the flux from a rectangular volume source  

SciTech Connect

An exact semi-analytic formula for the flux from a rectangular surface source with a slab shield has been derived and the required function table has been calculated. This formula is the basis for an algorithm which gives a good approximation for the flux from a rectangular volume source. No other hand calculation method for this source geometry is available in the literature.

Wallace, O.J.

1994-11-09T23:59:59.000Z

55

Visualization of Transient Natural Convection Heat Transfer from a Vertical Rectangular Fin  

Science Conference Proceedings (OSTI)

Experiments on thermal visualization of transient natural convection from short vertical rectangular fins were conducted using the technique of laser holographic interferometry. A sequence of infinite-fringe interferograms recorded for the heating regime ... Keywords: interferograms, laser holographic interferometry, thermal visualization, transient natural convection, vertical rectangular fins

K. C. Leong; T. C. Kooi

1998-12-01T23:59:59.000Z

56

Method for efficient prevention of gravity wave decoupling on rectangular semi-staggered grids  

Science Conference Proceedings (OSTI)

Generation of short gravity wave noise often occurs on semi-staggered rectangular grids as a result of sub-grid decoupling when there is a strong forcing in the mass field. In this study a numerical scheme has been proposed to prevent the generation ... Keywords: Divergence correction, Gravity wave, Rectangular grid

Slobodan Nickovic; Vladimir Djurdjevic; Mirjam Vujadinovic; Zavisa I. Janjic; Milan Curcic; Borivoj Rajkovic

2011-03-01T23:59:59.000Z

57

Radionuclide Retention in Concrete Wasteforms  

Science Conference Proceedings (OSTI)

Assessing long-term performance of Category 3 waste cement grouts for radionuclide encasement requires knowledge of the radionuclide-cement interactions and mechanisms of retention (i.e., sorption or precipitation); the mechanism of contaminant release; the significance of contaminant release pathways; how wasteform performance is affected by the full range of environmental conditions within the disposal facility; the process of wasteform aging under conditions that are representative of processes occurring in response to changing environmental conditions within the disposal facility; the effect of wasteform aging on chemical, physical, and radiological properties; and the associated impact on contaminant release. This knowledge will enable accurate prediction of radionuclide fate when the wasteforms come in contact with groundwater. The information present in the report provides data that (1) measures the effect of concrete wasteform properties likely to influence radionuclide migration; and (2) quantifies the rate of carbonation of concrete materials in a simulated vadose zone repository.

Bovaird, Chase C.; Jansik, Danielle P.; Wellman, Dawn M.; Wood, Marcus I.

2011-09-30T23:59:59.000Z

58

Quantitative study of rectangular waveguide behavior in the THz.  

SciTech Connect

This report describes our efforts to quantify the behavior of micro-fabricated THz rectangular waveguides on a configurable, robust semiconductor-based platform. These waveguides are an enabling technology for coupling THz radiation directly from or to lasers, mixers, detectors, antennas, and other devices. Traditional waveguides fabricated on semiconductor platforms such as dielectric guides in the infrared or co-planar waveguides in the microwave regions, suffer high absorption and radiative losses in the THz. The former leads to very short propagation lengths, while the latter will lead to unwanted radiation modes and/or crosstalk in integrated devices. This project exploited the initial developments of THz micro-machined rectangular waveguides developed under the THz Grand Challenge Program, but instead of focusing on THz transceiver integration, this project focused on exploring the propagation loss and far-field radiation patterns of the waveguides. During the 9 month duration of this project we were able to reproduce the waveguide loss per unit of length in the waveguides and started to explore how the loss depended on wavelength. We also explored the far-field beam patterns emitted by H-plane horn antennas attached to the waveguides. In the process we learned that the method of measuring the beam patterns has a significant impact on what is actually measured, and this may have an effect on most of the beam patterns of THz that have been reported to date. The beam pattern measurements improved significantly throughout the project, but more refinements of the measurement are required before a definitive determination of the beam-pattern can be made.

Rowen, Adam M.; Nordquist, Christopher Daniel; Wanke, Michael Clement

2009-10-01T23:59:59.000Z

59

Experimental study on rectangular barge in beam sea  

E-Print Network (OSTI)

This study presents laboratory observations of flow characteristics for regular waves passing a rectangular barge in a two dimensional wave tank. The rectangular barge was fixed and free to roll (one degree of freedom) in a beam sea. Particle image velocimetry (PIV) was employed to measure the velocity field in the vicinity of the structure. The mean velocity and turbulence properties were obtained by phase-averaging the velocity profiles from repeated test runs. The quantitative flow characteristics were represented to elucidate the coupled interactions between the regular wave and the barge in roll motion or fixed condition. Additionally, the turbulence properties including the turbulence length scale and the turbulent kinetic energy budget were investigated to characterize the flow pattern due to the wave interaction. Because all the data including wave elevations, roll motion, and dynamic pressure were synchronized with velocity profiles, the results between the roll motion and the fixed condition were compared. The viscous effects due to the flow separation depend on the relative relation between the wave water particle motion and the roll motion of the barge. The viscous damping mechanism that reduces the roll motion at the roll natural period wave is illustrated. It shows that the vortex flow was mainly induced by the roll motion. For wave periods longer than the roll natural period, the flow was separated in different directions accompanying the roll natural period wave. The longer waves may help the roll motion with the vortex flow predominantly separated by the wave water particle motion rather than the barge motion. This may be called the viscous exciting effect. Moreover, the variations of dynamic pressures near the corners were measured and analyzed along with the viscous effect for both the roll motion and the fixed barge cases.

Jung, Kwang-Hyo

2003-05-01T23:59:59.000Z

60

Magnetohydrodynamic lattice Boltzmann simulations of turbulence and rectangular jet flow  

E-Print Network (OSTI)

Magnetohydrodynamic (MHD) investigations of decaying isotropic turbulence and rectangular jets (RJ) are carried out. A novel MHD lattice Boltzmann scheme that combines multiple relaxation time (MRT) parameters for the velocity field with a single relaxation time (SRT) parameter for the Maxwells stress tensor is developed for this study. In the MHD homogeneous turbulence studies, the kinetic/magnetic energy and enstrophy decays, kinetic enstrophy evolution, and vorticity alignment with the strain-rate tensor are evaluated to assess the key physical MHD turbulence mechanisms. The magnetic and kinetic energies interact and exchange through the influence of the Lorentz force work. An initial random fluctuating magnetic field increases the vortex stretching and forward cascade mechanisms. A strong uniform mean magnetic field increases the anisotropy of the turbulent flow field and causes inverse cascading. In the RJ studies, an investigation into the MHD effects on velocity, instability, and the axis-switching phenomena is performed at various magnetic field strengths and Magnetic Reynolds Numbers. The magnetic field is found to decelerate the jet core, inhibit instability, and prevent axis-switching. The key physical mechanisms are: (i) the exchange of energy between kinetic and magnetic modes and (ii) the magnetic field effect on the vorticity evolution. From these studies, it is found that magnetic field influences momentum, vorticity, and energy evolution and the degree of modification depends on the field strength. This interaction changes vortex evolution, and alters turbulence processes and rectangular jet flow characteristics. Overall, this study provides more insight into the physics of MHD flows, which suggests possible applications of MHD Flow Control.

Riley, Benjamin Matthew

2007-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "rectangular precast concrete" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Project: Early-Age Performance of Concrete  

Science Conference Proceedings (OSTI)

... at the international workshop "Micro-structure, setting and aging of cement ... Solution Chemistry and Phase Evolution in Early-Age Concrete Materials ...

2012-12-31T23:59:59.000Z

62

Project: Long Term Performance of Concrete  

Science Conference Proceedings (OSTI)

... of a Performance-Based Specification for Cast-in-Place Concrete, RMC Research & Education Foundation, Phase 1 Final Report, 2006. ...

2013-06-28T23:59:59.000Z

63

NISTIR 7026 Condition Assessment of Concrete Nuclear ...  

Science Conference Proceedings (OSTI)

... An im- portant consideration for decommissioning is that the existing concrete nuclear structure is a primary barrier between its remaining contents ...

2003-12-16T23:59:59.000Z

64

Concrete & Asphalt Recycling into Reusable Products  

NLE Websites -- All DOE Office Websites (Extended Search)

SNLNM Pollution Prevention Concrete & Asphalt Recycling into Reusable Products (SNLNM Pollution Prevention Program) March 18, 2010 Doug Vetter, PE, LEED-AP Sandia is a...

65

Proceedings of the concrete decontamination workshop  

Science Conference Proceedings (OSTI)

Fourteen papers were presented. These papers describe concrete surface removal methods and equipment, as well as experiences in decontaminating and removing both power and experimental nuclear reactors.

Halter, J.M.; Sullivan, R.G.; Currier, A.J.

1980-05-28T23:59:59.000Z

66

The life cycle assessment of concrete manufacturing in Kuwait  

E-Print Network (OSTI)

Concrete is the second most widely used material in the world after water. Annually 9,120 million tons of concrete are produced, which is an equivalent of 1.3 tons of concrete per individual. As the world's primary ...

El Mostafa, Mayce (Mayce A.)

2013-01-01T23:59:59.000Z

67

Physics of relativistic electron beams in rectangular and cylindrical geometries  

SciTech Connect

The use of electron beams for the direct pumping of lasers for fusion applications requires the generation of large area beams in appropriate geometries. Two geometries which are of particular interest are rectangular electron beams with planar anodes and radially converging beams with cyclindrical anodes. The generation of such beams requires the management of electron trajectories in a complex combination of applied and self-generated electric and magnetic fields. The beam's self-electric field limits the emitted current and the deflection of the electron in the self-magnetic field (beam pinch) limits the beam area that can be generated from a single cathode. A simple analytic model is used to derive a scaling relationship for beam pinch in both geometries of the form V/sup 1/2/ w/d = $alpha$ where V is the diode voltage, w the beam width, d the anode-cathode spacing, and $alpha$ is a weak function of the geometry. Numerical calculations are presented to show the effects of nonuniform electric fields encountered in typical geometries together with supporting experimental measurements. (auth)

Schlitt, L.G.; Bradley, L.P.

1975-11-01T23:59:59.000Z

68

Diffraction of surface wave on conducting rectangular wedge  

E-Print Network (OSTI)

Diffraction of a surface wave on a rectangular wedge with impedance faces is studied using the Sommerfeld-Malyuzhinets technique. An analog of Landau's bypass rule in the theory of plasma waves is introduced for selection of a correct branch of the Sommerfeld integral, and the exact solution is given in terms of imaginary error function. The formula derived is valid both in the near-field and far-wave zones. It is shown that a diffracted surface wave is completely scattered into freely propagating electromagnetic waves and neither reflected nor transmitted surface waves are generated in case of bare metals which have positive real part of surface impedance. The scattered waves propagate predominantly at a grazing angle along the direction of propagation of the incident surface wave and mainly in the upper hemisphere regarding the wedge face. The profile of radiated intensity is nonmonotonic and does not resemble the surface wave profile which exponentially evanesces with the distance from the wedge face. Comparison with experiments carried out in the terahertz spectral range at Novosibirsk free electron laser has shown a good agreement of the theory and the experiments.

Igor A. Kotelnikov; Vasily V. Gerasimov; Boris A. Knyazev

2013-01-16T23:59:59.000Z

69

Radionuclide Retention in Concrete Wasteforms  

SciTech Connect

Assessing long-term performance of Category 3 waste cement grouts for radionuclide encasement requires knowledge of the radionuclide-cement interactions and mechanisms of retention (i.e., sorption or precipitation); the mechanism of contaminant release; the significance of contaminant release pathways; how wasteform performance is affected by the full range of environmental conditions within the disposal facility; the process of wasteform aging under conditions that are representative of processes occurring in response to changing environmental conditions within the disposal facility; the effect of wasteform aging on chemical, physical, and radiological properties; and the associated impact on contaminant release. This knowledge will enable accurate prediction of radionuclide fate when the wasteforms come in contact with groundwater. Data collected throughout the course of this work will be used to quantify the efficacy of concrete wasteforms, similar to those used in the disposal of LLW and MLLW, for the immobilization of key radionuclides (i.e., uranium, technetium, and iodine). Data collected will also be used to quantify the physical and chemical properties of the concrete affecting radionuclide retention.

Wellman, Dawn M.; Jansik, Danielle P.; Golovich, Elizabeth C.; Cordova, Elsa A.

2012-09-24T23:59:59.000Z

70

Concrete Foundations in Substations and Transmission Lines  

Science Conference Proceedings (OSTI)

This report presents the results of surveys conducted to obtain information on the degradation of concrete foundations that support transmission towers and high-voltage substation equipment. Although concrete foundations are simple and inexpensive, their degradation or failure may have costly consequences, including potential equipment damage and the need for outages to allow movement of critical equipment so the ...

2012-12-14T23:59:59.000Z

71

NISTIR 6295 Curing of High-Performance Concrete: Report of ...  

Science Conference Proceedings (OSTI)

... High-strength lightweight concreteConcrete produced by using lightweight aggregates, such as expanded clay, shale, and slate aggregates, so ...

1999-05-27T23:59:59.000Z

72

Life-Cycle Evaluation of Concrete Building Construction as a Strategy for Sustainable Cities  

E-Print Network (OSTI)

additives in concrete) and organic substances that are emitted during or shortly after the concrete manufacturing

Stadel, Alexander

2013-01-01T23:59:59.000Z

73

Quick-setting concrete and a method for making quick-setting concrete  

DOE Patents (OSTI)

This invention relates to a method for producing concrete, and more specifically, this invention relates to a method for producing quick-setting concrete while simultaneously minimizing the release of carbon dioxide to the atmosphere, said release of carbon dioxide inherent in cement production. A method for producing quick setting concrete comprises hydrating a concrete dry mixture with carbonate solution to create a slurry, and allowing the slurry to cure. The invention also provides for a quick setting concrete having a predetermined proportion of CaCO{sub 3} of between 5 and 23 weight percent of the entire concrete mixture, and whereby the concrete has a compression strength of approximately 4,000 pounds per square inch (psi) within 24 hours after pouring.

Wagh, A.S.; Singh, D.; Pullockaran, J.D.; Knox, L.

1995-12-31T23:59:59.000Z

74

STRUCTURAL PERFORMANCE OF DEGRADED REINFORCED CONCRETE MEMBERS.  

Science Conference Proceedings (OSTI)

This paper describes the results of a study to evaluate, in probabilistic terms, the effects of age-related degradation on the structural performance of reinforced concrete members at nuclear power plants. The paper focuses on degradation of reinforced concrete flexural members and shear walls due to the loss of steel reinforcing area and loss of concrete area (cracking/spalling). Loss of steel area is typically caused by corrosion while cracking and spalling can be caused by corrosion of reinforcing steel, freeze-thaw, or aggressive chemical attack. Structural performance in the presence of uncertainties is depicted by a fragility (or conditional probability of failure). The effects of degradation on the fragility of reinforced concrete members are calculated to assess the potential significance of various levels of degradation. The fragility modeling procedures applied to degraded concrete members can be used to assess the effects of degradation on plant risk and can lead to the development of probability-based degradation acceptance limits.

Braverman, J.I.; Miller, C.A.; Ellingwood, B.R.; Naus, D.J.; Hofmayer, C.H.; Bezler, P.; Chang, T.Y.

2001-03-22T23:59:59.000Z

75

Generation of transform-limited rectangular pulses in a spectral compressor  

SciTech Connect

The generation of 100-fs transform-limited pulses with a rectangular envelope in a spectral compressor is demonstrated experimentally. The pulses are characterised by spectral interferometry. (control of radiation parameters)

Kalashyan, M A; Palandzhyan, K A; Esayan, G L; Muradyan, L Kh [Department of Physics, Yerevan State University, Yerevan (Armenia)

2010-12-09T23:59:59.000Z

76

Special concrete shield selection using the analytic hierarchy process  

SciTech Connect

Special types of concrete radiation shields that depend on locally available materials and have improved properties for both neutron and gamma-ray attenuation were developed by using plastic materials and heavy ores. The analytic hierarchy process (AHP) is implemented to evaluate these types for selecting the best biological radiation shield for nuclear reactors. Factors affecting the selection decision are degree of protection against neutrons, degree of protection against gamma rays, suitability of the concrete as building material, and economic considerations. The seven concrete alternatives are barite-polyethylene concrete, barite-polyvinyl chloride (PVC) concrete, barite-portland cement concrete, pyrite-polyethylene concrete, pyrite-PVC concrete, pyrite-portland cement concrete, and ordinary concrete. The AHP analysis shows the superiority of pyrite-polyethylene concrete over the others.

Abulfaraj, W.H. (King Abdulaziz Univ., Jeddah (Saudi Arabia). Nuclear Engineering Dept.)

1994-08-01T23:59:59.000Z

77

Property:Description of Beach | Open Energy Information  

Open Energy Info (EERE)

Beach Beach Jump to: navigation, search Property Name Description of Beach Property Type Text Pages using the property "Description of Beach" Showing 24 pages using this property. A Alden Wave Basin + Designed as needed using commercially available sand/sediment C Carderock Maneuvering & Seakeeping Basin + Wave absorbers are a discontinuous 12 degree slope type made up of seven permeable layers of rectangular precast concrete bar panels resting on an impermeable beach, they are located along the full length of the two sides of the basin opposite the wavemaker units. Carderock Tow Tank 2 + The wave absorber spans the full width of the basin at the end opposite the wavemaker dome, the absorbers are a discontinuous 12 degree slope type made up of 12 permeable layers of rectangular precast concrete bar panels resting on an impermeable concrete slab supported by a structural steel framework, the center section of the absorber is of wood construction & can be raised and lowered as a unit to provide model access to and from the fitting-out dry dock located at the end of the basin.

78

Immobilization of iodine in concrete  

DOE Patents (OSTI)

A method for immobilizing fission product radioactive iodine recovered from irradiated nuclear fuel comprises combining material comprising water, Portland cement and about 3-20 wt. % iodine as Ba(IO.sub.3).sub.2 to provide a fluid mixture and allowing the fluid mixture to harden, said Ba(IO.sub.3).sub.2 comprising said radioactive iodine. An article for solid waste disposal comprises concrete prepared by this method. BACKGROUND OF THE INVENTION This invention was made in the course of, or under a contract with the Energy Research and Development Administration. It relates in general to reactor waste solidification and more specifically to the immobilization of fission product radioactive iodine recovered from irradiated nuclear fuel for underground storage.

Clark, Walter E. (Oak Ridge, TN); Thompson, Clarence T. (Oak Ridge, TN)

1977-04-12T23:59:59.000Z

79

Insulating polymer concrete for LNG impounding dikes. [Polymer concretes  

SciTech Connect

An insulating polymer concrete (IPC) composite has been developed under contract to the Gas Research Institute for possible use as a dike insulation material at Liquid Natural Gas (LNG) storage facilities. In the advent of an LNG spill into the impounding dike area, the boiloff rate of the LNG can be substantially reduced if the surfaces of the dike are insulated. This increased safety at the LNG facility will tend to reduce the hazardous explosive mixture with atmospheric air in the surrounding region. The dike insulation material must have a low thermal conductivity and be unaffected by environmental conditions. The IPC composites developed consist of perlite or glass nodule aggregates bound together as a closed cell structure with a polyester resin. In addition to low thermal conductivity and porosity, these composites have correspondingly high strengths and, therefore, can carry transient loads of workmen and maintenance equipment. Prefabricated IPC panels have been installed experimentally and at least one utility is currently considering a complete installation at its LNG facility. 5 refs., 5 tabs.

Fontana, J.J.; Steinberg, M.

1986-03-01T23:59:59.000Z

80

Air leakage of Insulated Concrete Form houses  

E-Print Network (OSTI)

Air leakage has been shown to increase building energy use due to additional heating and cooling loads. Although many construction types have been examined for leakage, an exploration of a large number of Insulated Concrete ...

Durschlag, Hannah (Hanna Rebekah)

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "rectangular precast concrete" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Variability in properties of Salado Mass Concrete  

SciTech Connect

Salado Mass Concrete (SMC) has been developed for use as a seal component in the Waste Isolation Pilot Plant. This concrete is intended to be mixed from pre-bagged materials, have an initial slump of 10 in., and remain pumpable and placeable for two hours after mixing. It is a mass concrete because it will be placed in monoliths large enough that the heat generated during cement hydration has the potential to cause thermal expansion and subsequent cracking, a phenomenon to avoid in the seal system. This report describes effects on concrete properties of changes in ratio of water to cement, batch size, and variations in characteristics of different lots of individual components of the concrete. The research demonstrates that the concrete can be prepared from laboratory-batched or pre-bagged dry materials in batches from 1.5 ft{sup 3} to 5.0 yd{sup 3}, with no chemical admixtures other than the sodium chloride added to improve bonding with the host rock, at a water-to-cement ratio ranging from 0.36 to 0.42. All batches prepared according to established procedures had adequate workability for at least 1.5 hours, and achieved or exceeded the target compressive strength of 4500 psi at 180 days after casting. Portland cement and fly ash from different lots or sources did not have a measurable effect on concrete properties, but variations in a shrinkage-compensating cement used as a component of the concrete did appear to affect workability. A low initial temperature and the water-reducing and set-retarding functions of the salt are critical to meeting target properties.

Wakeley, L.D.; Harrington, P.T. [US Army Engineer Waterways Experiment Station, Vicksburg, MS (United States); Hansen, F.D. [Sandia National Labs., Albuquerque, NM (United States)

1995-08-01T23:59:59.000Z

82

Energy Efficiency Improvement and Cost Saving Oportunities for the Concrete Industry  

E-Print Network (OSTI)

costs. Mechanical concrete reclaimer. Concrete returned tothrough a mechanical reclaimer, able to separate aggregatesobtaining a concrete reclaimer is significant and according

Kermeli, Katerina

2013-01-01T23:59:59.000Z

83

Final Technical Report HFC Concrete: A Low-???????­???¢???????Energy, Carbon-???????­Dioxide-???????­Negative Solution for reducing Industrial Greenhouse Gas Emissions  

SciTech Connect

Solidia/CCSM received funding for further research and development of its Low Temperature Solidification Process (LTS), which is used to create hydrate-free concrete (HFC). LTS/HFC is a technology/materials platform that offers wide applicability in the built infrastructure. Most importantly, it provides a means of making concrete without Portland cement. Cement and concrete production is a major consumer of energy and source of industrial greenhouse gas (GHG) emissions. The primary goal of this project was to develop and commercialize a novel material, HFC, which by replacing traditional concrete and cement, reduces both energy use and GHG emissions in the built infrastructure. Traditional concrete uses Portland Cement (PC) as a binder. PC production involves calcination of limestone at {approx}1450 C, which releases significant amounts of CO{sub 2} gas to the atmosphere and consumes a large amount of energy due to the high temperature required. In contrast, HFC is a carbonate-based hydrate-free concrete (HFC) that consumes CO{sub 2} gas in its production. HFC is made by reaction of silicate minerals with CO{sub 2} at temperatures below 100 C, more than an order-of-magnitude below the temperature required to make PC. Because of this significant difference in temperature, it is estimated that we will be able to reduce energy use in the cement and concrete industry by up to 30 trillion Btu by 2020. Because of the insulating properties of HFC, we believe we will also be able to significantly reduce energy use in the Building sector, though the extent of this saving is not yet quantified. It is estimated that production of a tonne of PC-based concrete requires about 6.2 million Btu of energy and produces over 1 tonne of CO{sub 2} emissions (Choate, 2003). These can be reduced to 1.9 million Btu and 0.025 tonnes of CO{sub 2} emissions per tonne of HFC (with overall CO{sub 2}-negativity possible by increasing carbonation yield). In this way, by replacing PC-based concrete with HFC in infrastructure we can reduce energy use in concrete production by 70%, and reduce CO{sub 2} emissions by 98%; thus the potential to reduce the impact of building materials on global warming and climate change is highly significant. Low Temperature Solidification (LTS) is a breakthrough technology that enables the densification of inorganic materials via a hydrothermal process. The resulting product exhibits excellent control of chemistry and microstructure, to provide durability and mechanical performance that exceeds that of concrete or natural stone. The technology can be used in a wide range of applications including facade panels, interior tiles, roof tiles, countertops, and pre-cast concrete. Replacing traditional building materials and concrete in these applications will result in significant reduction in both energy consumption and CO{sub 2} emissions.

Dr. Larry McCandlish, Principal Investigator; Dr. Richard Riman, Co-Principal Investigator

2012-05-14T23:59:59.000Z

84

SUSTAINABLE CONCRETE FOR WIND TURBINE FOUNDATIONS.  

SciTech Connect

The use of wind power to generate electricity continues to grow, especially given commitments by various countries throughout the world to ensure that a significant percentage of energy comes from renewable sources. In order to meet such objectives, increasingly larger turbines with higher capacity are being developed. The engineering aspects of larger turbine development tend to focus on design and materials for blades and towers. However, foundations are also a critical component of large wind turbines and represent a significant cost of wind energy projects. Ongoing wind research at BNL is examining two areas: (a) structural response analysis of wind turbine-tower-foundation systems and (b) materials engineering of foundations. This work is investigating the dynamic interactions in wind turbine systems, which in turn assists the wind industry in achieving improved reliability and more cost efficient foundation designs. The results reported herein cover initial studies of concrete mix designs for large wind turbine foundations and how these may be tailored to reduce cost and incorporate sustainability and life cycle concepts. The approach taken was to investigate material substitutions so that the environmental, energy and CO{sub 2}-impact of concrete could be reduced. The use of high volumes of ''waste'' materials in concrete was examined. These materials included fly ash, blast furnace slag and recycled concrete aggregate. In addition, the use of steel fiber reinforcement as a means to improve mechanical properties and potentially reduce the amount of bar reinforcement in concrete foundations was studied. Four basic mixes were considered. These were: (1) conventional mix with no material substitutions, (2) 50% replacement of cement with fly ash, (3) 50% replacement of cement with blast furnace slag and (4) 25% replacement of cement with fly ash and 25% replacement with blast furnace slag. Variations on these mixes included the addition of 1% by volume steel fibers. The use of recycled concrete aggregate in the conventional and 50% slag mixes was also studied. Properties investigated included compressive and tensile strengths, elastic modulus, coefficient of permeability, thermal conductivity and durability in seawater and sulfate solutions. It was determined that the mixes containing 50% slag gave the best overall performance. Slag was particularly beneficial for concrete that used recycled aggregate and could reduce strength losses. Initial durability results indicated that corrosion of fibers in the different concrete mixes when exposed to seawater was minimal. Future research needs to include more detailed studies of mix design and properties of concrete for wind turbine foundations. Emphasis on slag-modified mixes with natural and recycled concrete aggregate is recommended. The proportion of slag that can be incorporated in the concrete needs to be optimized, as does the grading of recycled aggregate. The potential for using silica fume in conjunction with slag is worth exploring as this may further enhance strength and durability. Longer-term durability studies are necessary and other pertinent properties of concrete that require investigation include damping characteristics, pullout strength, fatigue strength and risk of thermal cracking. The properties of sustainable concrete mixes need to be integrated with studies on the structural behavior of wind turbine foundations in order to determine the optimal mix design and to examine means of reducing conservatism and cost of foundations.

BERNDT,M.L.

2004-06-01T23:59:59.000Z

85

Nuclear Concrete Materials Database Phase I Development  

Science Conference Proceedings (OSTI)

The FY 2011 accomplishments in Phase I development of the Nuclear Concrete Materials Database to support the Light Water Reactor Sustainability Program are summarized. The database has been developed using the ORNL materials database infrastructure established for the Gen IV Materials Handbook to achieve cost reduction and development efficiency. In this Phase I development, the database has been successfully designed and constructed to manage documents in the Portable Document Format generated from the Structural Materials Handbook that contains nuclear concrete materials data and related information. The completion of the Phase I database has established a solid foundation for Phase II development, in which a digital database will be designed and constructed to manage nuclear concrete materials data in various digitized formats to facilitate electronic and mathematical processing for analysis, modeling, and design applications.

Ren, Weiju [ORNL; Naus, Dan J [ORNL

2012-05-01T23:59:59.000Z

86

TRANSPORT THROUGH CRACKED CONCRETE: LITERATURE REVIEW  

SciTech Connect

Concrete containment structures and cement-based fills and waste forms are used at the Savannah River Site to enhance the performance of shallow land disposal systems designed for containment of low-level radioactive waste. Understanding and measuring transport through cracked concrete is important for describing the initial condition of radioactive waste containment structures at the Savannah River Site (SRS) and for predicting performance of these structures over time. This report transmits the results of a literature review on transport through cracked concrete which was performed by Professor Jason Weiss, Purdue University per SRR0000678 (RFP-RQ00001029-WY). This review complements the NRC-sponsored literature review and assessment of factors relevant to performance of grouted systems for radioactive waste disposal. This review was performed by The Center for Nuclear Waste Regulatory Analyses, San Antonio, TX, and The University of Aberdeen, Aberdeen Scotland and was focused on tank closure. The objective of the literature review on transport through cracked concrete was to identify information in the open literature which can be applied to SRS transport models for cementitious containment structures, fills, and waste forms. In addition, the literature review was intended to: (1) Provide a framework for describing and classifying cracks in containment structures and cementitious materials used in radioactive waste disposal, (2) Document the state of knowledge and research related to transport through cracks in concrete for various exposure conditions, (3) Provide information or methodology for answering several specific questions related to cracking and transport in concrete, and (4) Provide information that can be used to design experiments on transport through cracked samples and actual structures.

Langton, C.

2012-05-11T23:59:59.000Z

87

Dual variational principle for a problem of heat conduction in a rectangular plate  

Science Conference Proceedings (OSTI)

In this paper we formulate the dual variational principle for a problem of heat conduction in a rectangular domain, represented by elliptic equation with boundary conditions (Dirichlet-Neumann). The approximate solution for the dual variational problem ... Keywords: dual functional, heat transfer, weak solution

Mioara Boncu?; Dumitru Barac

2010-07-01T23:59:59.000Z

88

Gas Explosion Tests on East Jordan Iron Works Rectangular Composite Secondary Box Covers for Con Edison  

Science Conference Proceedings (OSTI)

This report is an account of continuing research by Con Edison and EPRI to address issues related to manhole events caused by the accumulation of gases in underground structures. It summarizes the results of gas explosion tests performed in June 2008 on rectangular composite vented covers produced by East Jordan Iron Works Company.

2009-07-21T23:59:59.000Z

89

Global Century IMPORTANT NOTICE  

E-Print Network (OSTI)

· Dualheatexchanger o Hot-water storage tank connects three systems in the house: the open domestic hot-water loop · Radiantconcreteflooring o Concrete flooring contains coils filled with water used as a space heater in winter o Heating#12;16 Precast solutions | Winter 2012 stunning Precast concrete solar home incorPorates latest

Chu, Xi

90

Maintenance-based design of concrete parking structures  

E-Print Network (OSTI)

The purpose of this study is to determine what type of preventative maintenance for a concrete parking structure will produce the maximum economic benefit. Existing models for concrete deterioration are analyzed for their ...

Stoakes, Christopher D. (Christopher David)

2007-01-01T23:59:59.000Z

91

Set in stone? A perspective on the concrete sustainability challenge  

E-Print Network (OSTI)

As the most abundant engineered material on Earth, concrete is essential to the physical infrastructure of all modern societies. There are no known materials that can replace concrete in terms of cost and availability. ...

Vliet, Krystyn Van J.

92

Material flow analysis of concrete in the United States  

E-Print Network (OSTI)

Concrete is the second most consumed material in the world after water. Due to the sheer mass of concrete consumed annually and its associated resource and environmental impacts, improving the materials management of ...

Low, Man-Shi

2005-01-01T23:59:59.000Z

93

The Complexity of Description Logics with Concrete Domains  

E-Print Network (OSTI)

of Concrete Domains . . . . . . . . . . . . . . . . . . . . . . 31 2.4.1 Unary Concrete Domains and ALCf Domains . . . . . . . . . . . . . . . . . . . 36 3 Reasoning with ALCF(D) 41 3.1 Concept Satis#12;ability: ALCF . . . . . . . . . . . . . . . . . . . . . . . . 78 4.3 The Upper Bound

Baader, Franz

94

The Complexity of Description Logics with Concrete Domains  

E-Print Network (OSTI)

of Concrete Domains . . . . . . . . . . . . . . . . . . . . . . 31 2.4.1 Unary Concrete Domains and ALCf Domains . . . . . . . . . . . . . . . . . . . 36 3 Reasoning with ALCF(D) 41 3.1 Concept Satisfiability: ALCF . . . . . . . . . . . . . . . . . . . . . . . . 78 4.3 The Upper Bound

Baader, Franz

95

NEXPTIME-Complete Description Logics with Concrete Domains  

Science Conference Proceedings (OSTI)

Concrete domains are an extension of Description Logics (DLs) allowing to integrate reasoning about conceptual knowledge with reasoning about "concrete properties" of objects such as sizes, weights, and durations. It is known that reasoning with ALC(D), ...

Carsten Lutz

2001-06-01T23:59:59.000Z

96

Chloride-Exposed Steel-Reinforced Concrete Service Life ...  

Science Conference Proceedings (OSTI)

Chloride-Exposed Steel-Reinforced Concrete Service Life Prediction Program. Description/Summary: (Return to Cement ...

2013-06-11T23:59:59.000Z

97

Predicting the Permeability of Pervious Concretes from Planar ...  

Science Conference Proceedings (OSTI)

... Permeability predictions for sand- clogged Portland cement pervious concrete pavement systems, Journal of Environmental Management 81, 42 ...

2009-05-26T23:59:59.000Z

98

Best Practices Guide for High-Volume Fly Ash Concretes:  

Science Conference Proceedings (OSTI)

... Concrete Mixtures [7]. This online, interactive tool provides guidelines ... cement type (alkali level), opening time requirements, and paving weather. ...

2013-09-19T23:59:59.000Z

99

Investigation on Lightweight High-Volume Fly Ash Concrete  

Science Conference Proceedings (OSTI)

This report presents the results of a study that developed an engineering data base on HVFA lightweight concrete. The investigation also identified potential problems that might be experienced in commercializing lightweight concrete production. The study was based on the use of high volume flyash (HVFA) in the concrete process.

1997-03-26T23:59:59.000Z

100

Center for By-Products Utilization Sustainable Concrete with  

E-Print Network (OSTI)

-Products Utilization Geopolymer Concrete (GPC) · Proposed by Devidovits (1994) is an upcoming technology-friendly and sustainable. #12;Center for By-Products Utilization Geopolymer Concrete (cont'd) · Industrial byCenter for By-Products Utilization Sustainable Concrete with Industrial and Post-Consumer By

Saldin, Dilano

Note: This page contains sample records for the topic "rectangular precast concrete" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

A Hybrid Solution Approach for Ready-Mixed Concrete Delivery  

Science Conference Proceedings (OSTI)

Companies in the concrete industry are facing the following scheduling problem on a daily basis: Concrete produced at several plants has to be delivered at customers' construction sites using a heterogeneous fleet of vehicles in a timely, but cost-effective ... Keywords: hybrid approach, integer multicommodity flow, ready-mixed concrete delivery, variable neighborhood search

Verena Schmid; Karl F. Doerner; Richard F. Hartl; Martin W. P. Savelsbergh; Wolfgang Stoecher

2009-02-01T23:59:59.000Z

102

Reinforced concrete perforation and penetration simulation using AUTODYN-3D  

Science Conference Proceedings (OSTI)

3D hydrocode simulation on the perforation and penetration of reinforced concrete target has been performed. The simulation aims to examine the influence of the following constitutive models for concrete on a projectile's residual velocity: (1) constant-yield ... Keywords: Constitutive model, Hydrocode, Perforation, Projectile, Reinforced concrete

C. Y. Tham

2005-08-01T23:59:59.000Z

103

NEXP TIME-complete description logics with concrete domains  

Science Conference Proceedings (OSTI)

Concrete domains are an extension of Description Logics (DLs) that allow one to integrate reasoning about conceptual knowledge with reasoning about "concrete qualities" of real-world entities such as their sizes, weights, and durations. In this article, ... Keywords: Computational complexity, NExpTime-completeness, concrete domains, description logic, domino problem, post correspondence problem

Carsten Lutz

2004-10-01T23:59:59.000Z

104

Numerical simulations of oblique penetration into reinforced concrete targets  

Science Conference Proceedings (OSTI)

A dynamic constitutive model based on the tensile and the compressive damage models for concrete was developed and implemented into the three-dimensional finite element code, LS-DYNA. Numerical simulations of oblique penetration into reinforced concrete ... Keywords: Dynamic damage model, Numerical simulation, Oblique penetration, Reinforced concrete

Yan Liu; Fenglei Huang; Aie Ma

2011-04-01T23:59:59.000Z

105

Predict strength of rubberized concrete using atrificial neural network  

Science Conference Proceedings (OSTI)

In this paper, behaviour of rubberized concrete was modelled using artificial neural network ANN and obtained results were compared to experimental data. Experimental test include recycling 5, 10, 15 and 20% percentage of concrete aggregate with different ... Keywords: artificial neural network, multi linear regression, root mean square, rubberized concrete

A. Abdollahzadeh; R. Masoudnia; S. Aghababaei

2011-02-01T23:59:59.000Z

106

A plastic damage approach for confined concrete  

Science Conference Proceedings (OSTI)

There are many situations in which it is necessary to increase the capacity of structures in use. This need maybe either for a change of use or because the structures have suffered some damage or have shown little resistance in case of extreme loads ... Keywords: Concrete, Confinement, Damage, Dilation, Fiber reinforced composites, Plasticity

B. M. Luccioni; V. C. Rougier

2005-10-01T23:59:59.000Z

107

Nuclear waste package fabricated from concrete  

Science Conference Proceedings (OSTI)

After the United States enacted the Nuclear Waste Policy Act in 1983, the Department of Energy must design, site, build and operate permanent geologic repositories for high-level nuclear waste. The Department of Energy has recently selected three sites, one being the Hanford Site in the state of Washington. At this particular site, the repository will be located in basalt at a depth of approximately 3000 feet deep. The main concern of this site, is contamination of the groundwater by release of radionuclides from the waste package. The waste package basically has three components: the containment barrier (metal or concrete container, in this study concrete will be considered), the waste form, and other materials (such as packing material, emplacement hole liners, etc.). The containment barriers are the primary waste container structural materials and are intended to provide containment of the nuclear waste up to a thousand years after emplacement. After the containment barriers are breached by groundwater, the packing material (expanding sodium bentonite clay) is expected to provide the primary control of release of radionuclide into the immediate repository environment. The loading conditions on the concrete container (from emplacement to approximately 1000 years), will be twofold; (1) internal heat of the high-level waste which could be up to 400/sup 0/C; (2) external hydrostatic pressure up to 1300 psi after the seepage of groundwater has occurred in the emplacement tunnel. A suggested container is a hollow plain concrete cylinder with both ends capped. 7 refs.

Pfeiffer, P.A.; Kennedy, J.M.

1987-03-01T23:59:59.000Z

108

Safety Concrete Principal Investigators: Hamlin Jennings  

E-Print Network (OSTI)

is to minimize casualties from large fragments of concrete propelled by a vehicle bomb detonated outside TO REDUCE BLAST-RELATED CASUALTIES Edward F. O'Neil, Hamlin Jennings, Jeffrey Thomas, Weiguo Shen, Toney materials. Jeffrey Thomas is a Professor of Civil Engineering whose primary research interest is the atomic

109

Types and Causes of Concrete Degradation  

Science Conference Proceedings (OSTI)

Table 2   Chemicals that deteriorate concrete...butter (a) Coconut oil (a) Cottonseed oil (a) Fish liquor (b) Mustard oil (a) Perchloric acid, 10% Potassium dichromate Potassium hydroxide (>20%) Rapeseed oil (a) Slaughterhouse waste (c) Sodium bisulfate Sodium bisulfite Sodium hydroxide (>20%) Sulfite liquor Sulfuric acid, 80% oleum (a) Tanning...

110

Implementation Plan and Initial Development of Nuclear Concrete Materials  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Implementation Plan and Initial Development of Nuclear Concrete Implementation Plan and Initial Development of Nuclear Concrete Materials Database for Light Water Reactor Sustainability Program Implementation Plan and Initial Development of Nuclear Concrete Materials Database for Light Water Reactor Sustainability Program The FY10 activities for development of a nuclear concrete materials database to support the Light Water Reactor Sustainability Program are summarized. The database will be designed and constructed using the ORNL materials database infrastructure established for the Gen IV Materials Handbook to achieve cost reduction and development efficiency. In Phase I, a static database will be developed to manage searchable documents from the Structural Materials Handbook that contains information on nuclear concrete

111

Implementation Plan and Initial Development of Nuclear Concrete Materials  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Implementation Plan and Initial Development of Nuclear Concrete Implementation Plan and Initial Development of Nuclear Concrete Materials Database for Light Water Reactor Sustainability Program Implementation Plan and Initial Development of Nuclear Concrete Materials Database for Light Water Reactor Sustainability Program The FY10 activities for development of a nuclear concrete materials database to support the Light Water Reactor Sustainability Program are summarized. The database will be designed and constructed using the ORNL materials database infrastructure established for the Gen IV Materials Handbook to achieve cost reduction and development efficiency. In Phase I, a static database will be developed to manage searchable documents from the Structural Materials Handbook that contains information on nuclear concrete

112

Concrete decontamination by Electro-Hydraulic Scabbling (EHS)  

SciTech Connect

EHS is being developed for decontaminating concrete structures from radionuclides, organic substances, and hazardous metals. EHS involves the generation of powerful shock waves and intense cavitation by a strong pulsed electric discharge in a water layer at the concrete surface; high impulse pressure results in stresses which crack and peel off a concrete layer of controllable thickness. Scabbling produces contaminated debris of relatively small volume which can be easily removed, leaving clean bulk concrete. Objective of Phase I was to prove the technical feasibility of EH for controlled scabbling and decontamination of concrete. Phase I is complete.

NONE

1994-11-01T23:59:59.000Z

113

A P R I L 2 0 0 9 Imagination is more important than knowledge. Knowledge is  

E-Print Network (OSTI)

of Geopolymer Concrete (Envirocrete) in Pre-Cast Components and Field Construction Entergy Nuclear 60,956 Alice NSF/BoR 18,250 Erez Allouche Applications of Inorganic Polymer Concrete (Geopolymer) in Transportation

Selmic, Sandra

114

J A N U A R Y 2 0 0 8 If I have been able to see farther than others, it was because I  

E-Print Network (OSTI)

of Geopolymer Concrete (Envirocrete) in Pre-Cast Components and Field Construction Entergy Nuclear 60,956 Alice NSF/BoR 18,250 Erez Allouche Applications of Inorganic Polymer Concrete (Geopolymer) in Transportation

Selmic, Sandra

115

S E P T E M B E R 2 0 0 7 In every adversity there lies the seed of an equivalent advantage.  

E-Print Network (OSTI)

of Geopolymer Concrete (Envirocrete) in Pre-Cast Components and Field Construction Entergy Nuclear 60,956 Alice NSF/BoR 18,250 Erez Allouche Applications of Inorganic Polymer Concrete (Geopolymer) in Transportation

Selmic, Sandra

116

THSE DE DOCTORAT DE L'UNIVERSIT PIERRE ET MARIE CURIE  

E-Print Network (OSTI)

of Geopolymer Concrete (Envirocrete) in Pre-Cast Components and Field Construction Entergy Nuclear 60,956 Alice NSF/BoR 18,250 Erez Allouche Applications of Inorganic Polymer Concrete (Geopolymer) in Transportation

117

Two Channel Dielectric-Lined Rectangular High Transformer Ratio Accelerator Structure Experiment  

SciTech Connect

Current status of a two-channel cm-scale rectangular dielectric lined wakefield accelerator structure is described. This structure is installed at the Argonne Wakefield Accelerator facility (AWA), and is presently being evaluated. The device has a transformer ratio of {approx}12.5:1. When driven by a {approx}50 nC single drive bunch it is expected to obtain {approx}6 MV/m acceleration gradient. Related issues are discussed.

Shchelkunov, S. V.; LaPointe, M. A. [Beam Physics Laboratory, Yale University, 272 Whitney Avenue, New Haven, CT 06511 (United States); Hirshfield, J. L. [Beam Physics Laboratory, Yale University, 272 Whitney Avenue, New Haven, CT 06511 (United States); Omega-P, Inc., 258 Bradley St., New Haven, CT 06510 (United States); Marshall, T. C. [Columbia University, New York, NY 10027 (United States); Omega-P, Inc., 258 Bradley St., New Haven, CT 06510 (United States); Sotnikov, G. [NSC Kharkov Institute of Physics and Technology, Kharkov (Ukraine); Omega-P, Inc., 258 Bradley St., New Haven, CT 06510 (United States); Gai, Wei; Conde, M.; Power, J.; Mihalcea, D. [Argonne National Laboratory, Argonne, IL 60439 (United States)

2010-11-04T23:59:59.000Z

118

Multiple solutions of gravity and surface shear driven thin film flows over a rectangular cavity  

Science Conference Proceedings (OSTI)

The effect of surface shear stress on the two-dimensional flow of a thin film over a rectangular cavity is investigated by the numerical simulation of the problem in terms of its corresponding Stokes formulation. The integral representation of the problem is numerically solved by a direct boundary element method(BEM) with primitive variables of velocity and surface traction. For cases in which the applied surface shear and the gravity act in opposite directions

N. H. Shuaib; H. Power; S. Hibberd

2006-01-01T23:59:59.000Z

119

GARCON: Genetic Algorithm for Rectangular Cuts OptimizatioN. User's manual for version 2.0  

E-Print Network (OSTI)

This paper presents GARCON program, illustrating its functionality on a simple HEP analysis example. The program automatically performs rectangular cuts optimization and verification for stability in a multi-dimensional phase space. The program has been successfully used by a number of very different analyses presented in the CMS Physics Technical Design Report. The current version GARCON 2.0 incorporates the feedback the authors have received. User's Manual is included as a part of the note.

S. Abdullin; D. Acosta; P. Bartalini; R. Cavanaugh; A. Drozdetskiy; G. Karapostoli; G. Mitselmakher; Yu. Pakhotin; B. Scurlock; M. Spiropulu

2006-05-12T23:59:59.000Z

120

Impact of aspect ratio on flow boiling of water in rectangular microchannels  

SciTech Connect

In this paper we focus on the impact of varying the aspect ratio of rectangular microchannels, on the overall pressure drop involving water boiling. An integrated system comprising micro-heaters, sensors and microchannels has been realized on (110) silicon wafers, following CMOS compatible process steps. Rectangular microchannels were fabricated with varying aspect ratios (width [W] to depth [H]) but constant hydraulic diameter of 142{+-}2{mu}m and length of 20 mm. The invariant nature of the hydraulic diameter is confirmed through two independent means: physical measurements using profilometer and by measuring the pressure drop in single-phase fluid flow. The experimental results show that the pressure drop for two-phase flow in rectangular microchannels experiences minima at an aspect ratio of about 1.6. The minimum is possibly due to opposing trends of frictional and acceleration pressure drops, with respect to aspect ratio. In a certain heat flux and mass flux range, it is observed that the two-phase pressure drop is lower than the corresponding single-phase value. This is the first study to investigate the effect of aspect ratio in two-phase flow in microchannels, to the best of our knowledge. The results are in qualitative agreement with annular flow model predictions. These results improve the possibility of designing effective heat-sinks based on two-phase fluid flow in microchannels. (author)

Singh, S.G.; Kulkarni, A.; Duttagupta, S.P. [Nanoelectronics Center, Department of Electrical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400 076 (India); Puranik, B.P.; Agrawal, A. [Suman Mashruwala Lab, Department of Mechanical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400 076 (India)

2008-10-15T23:59:59.000Z

Note: This page contains sample records for the topic "rectangular precast concrete" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Reasoning with Concrete Domains Carsten Lutz  

E-Print Network (OSTI)

and fea­ ture disagreement. This leads to the new logic ALCF(D), which combines ALC(D) with the logic ALCF problems for the logic ALCF(D) are given. Furthermore, the complexity of rea­ soning with ALCF(D) is formally analyzed. Since reason­ ing with ALCF(D) involves a satisfiability check for the concrete domain

Baader, Franz

122

Radionuclide Retention in Concrete Waste Forms  

Science Conference Proceedings (OSTI)

Assessing long-term performance of Category 3 waste cement grouts for radionuclide encasement requires knowledge of the radionuclide-cement interactions and mechanisms of retention (i.e., sorption or precipitation); the mechanism of contaminant release; the significance of contaminant release pathways; how waste form performance is affected by the full range of environmental conditions within the disposal facility; the process of waste form aging under conditions that are representative of processes occurring in response to changing environmental conditions within the disposal facility; the effect of waste form aging on chemical, physical, and radiological properties; and the associated impact on contaminant release. This knowledge will enable accurate prediction of radionuclide fate when the waste forms come in contact with groundwater. The information presented in the report provides data that 1) quantify radionuclide retention within concrete waste form materials similar to those used to encapsulate waste in the Low-Level Waste Burial Grounds (LLBG); 2) measure the effect of concrete waste form properties likely to influence radionuclide migration; and 3) quantify the stability of uranium-bearing solid phases of limited solubility in concrete.

Mattigod, Shas V.; Bovaird, Chase C.; Wellman, Dawn M.; Wood, Marcus I.

2010-09-30T23:59:59.000Z

123

Goal 4 Long Life Pavement Rehabilitation Strategies-Rigid: Flexural Fatigue Life of Hydraulic Cement Concrete Beams  

E-Print Network (OSTI)

Flexural Fatigue Life of Hydraulic Cement Concrete Beamsperformance of Fast-Setting Hydraulic Cement Concrete (and Thermal Expansion of Hydraulic Cement Concrete Mixes,

Kohler, Erwin R.; Ali, Abdikarim; Harvey, John T

2005-01-01T23:59:59.000Z

124

Environmental and Corrosion Effects on Reinforced Concrete Foundations  

Science Conference Proceedings (OSTI)

The large number of transmission structures with concrete foundations that the electric industry maintains makes it important to develop efficient ways to monitor their condition and remediate damage, especially since the largest population of concrete foundations is 20-40 years old; and almost 40 of foundations are more than 40 years old. This report discusses the environmental and corrosion effects that affect steel-reinforced concrete foundations, including problems caused by poor construction, freezi...

2011-12-22T23:59:59.000Z

125

Evaluation of sustainable high-volume fly ash concretes  

Science Conference Proceedings (OSTI)

... All rights reserved. ... and by the concrete mixture proportions; in this scenario, one key con- crete material property is the energy generated within the ...

2013-08-09T23:59:59.000Z

126

Guidelines for identification of concrete in a materials property database  

SciTech Connect

Guidelines for the identification of concrete in a materials property database are presented to address the complex problem of distinguishing one concrete from another. These guidelines are based on a logical scheme for systematically organizing and subdividing data and information about concrete and its constituents; they reflect consensus recommendations for a multilevel material description and designation system. Aspects of the guidelines include a classification system used to establish a series of primary identifiers, methods for reporting constituent information and mixture proportions, fields describing the source of the concrete and its processing history, and recommendations for reporting baseline or reference properties.

Oland, C.B. [Oak Ridge National Lab., TN (United States). Engineering Technology Div.; Frohnsdorff, G. [National Inst. of Standards and Technology, Gaithersburg, MD (United States)

1995-12-31T23:59:59.000Z

127

The use of gasification ash in cement and concrete.  

E-Print Network (OSTI)

?? Cement is an essential material in todays society because, as a major constituent of concrete, it forms a fundamental element of any housing or (more)

Du Plessis, Hanli

2007-01-01T23:59:59.000Z

128

Risk-Based Radionuclide DCGLs for Concrete Slab End States  

Argonne National Laboratory (DOE, NRC, EPA) Adjustment of Relevant Parameters and Exposure Factors Concrete End-State vs. Soil (Preliminary Remediation Goals)

129

Saving Energy in Ready Mixed Concrete Production: An ENERGY STAR...  

NLE Websites -- All DOE Office Websites (Extended Search)

Saving Energy in Ready Mixed Concrete Production: An ENERGY STAR Quick Guide for Managing Energy Secondary menu About us Press room Contact Us Portfolio Manager Login Facility...

130

Studies of Tritium Characterization in Concrete at the ...  

Studies of Tritium Characterization in Concrete at the Savannah River Site Robert C. Hochel#, Elliot A. Clark* #Analytical Development, *Materials Science and Technology

131

Characterizing Blast and Impact of Long Carbon Fiber Reinforced Concrete.  

E-Print Network (OSTI)

??The primary objective of the study was to investigate the blast and impact resistance of carbon fiber reinforced concrete. The impact resistance was assessed through (more)

Musselman, Eric

2007-01-01T23:59:59.000Z

132

Concrete Industry Benefits from Ancient Romans and the ALS  

NLE Websites -- All DOE Office Websites (Extended Search)

the structure before it's immobilized. This process is important for the modern concrete industry because chloride corrosion of steel reinforcement is a major source of decay....

133

Concrete Industry Benefits from Ancient Romans and the ALS  

NLE Websites -- All DOE Office Websites (Extended Search)

into the structure before it's immobilized. This process is important for the modern concrete industry because chloride corrosion of steel reinforcement is a major source of decay....

134

Investigation of Uplift Pressures and Shear and Tensile Strengths for Concrete Gravity Dams  

Science Conference Proceedings (OSTI)

Concrete gravity dam stability depends on the characteristics of the rock foundation, strength of the concrete-to-rock bond, concrete strength, and uplift pressure forces. This interim report describes, with examples, how to assess these factors.

1990-12-17T23:59:59.000Z

135

Development of a Reaction Signature for Combined Concrete Materials  

E-Print Network (OSTI)

Although concrete is widely considered a very durable material, if conditions are such, it can be vulnerable to deterioration and early distress development. Alkali-Silica Reaction (ASR) is a major durability problem in concrete structures. It is a chemical reaction between the reactive silica existent in some types of rocks and alkali hydroxides in the concrete pore water. The product of this reaction is a gel that is hygroscopic in nature. When the gel absorbs moisture, it swells leading to tensile stresses in concrete. When those stresses exceed the tensile strength of concrete, cracks occur. The main objective of this study was to address a method of testing concrete materials as a combination to assist engineers to effectively mitigate ASR in concrete. The research approach involved capturing the combined effects of concrete materials (water cement ratio, porosity, supplementary cementitious materials, etc.) through a method of testing to allow the formulation of mixture combinations resistant to ASR leading to an increase in the life span of concrete structures. To achieve this objective, a comprehensive study on different types of aggregates of different reactivity was conducted to formulate a robust approach that takes into account the factors affecting ASR; such as, temperature, moisture, calcium concentration and alkalinity. A kinetic model was proposed to determine aggregate ASR characteristics which were calculated using the System Identification Method. Analysis of the results validates that ASR is a thermally activated process and therefore, the reactivity of an aggregate can be characterized in terms of its activation energy (Ea) using the Arrhenius equation. Statistical analysis was conducted to determine that the test protocol is highly repeatable and reliable. To relate the effect of material combinations to field performance, concrete samples with different w/cm?s and fly ash contents using selective aggregates were tested at different alkalinities. To combine aggregate and concrete characteristics, two models were proposed and combined. The first model predicts the Ea of the aggregate at levels of alkalinity similar to field conditions. The second model, generated using the Juarez- Badillo transform, connects the ultimate expansion of the concrete and aggregate, the water cement ratio, and the fly ash content to the Ea of the rock. The proposed models were validated through laboratory tests. To develop concrete mixtures highly resistant to ASR, a sequence of steps to determine threshold total alkali in concrete were presented with examples. It is expected that the knowledge gained through this work will assist government agencies, contractors, and material engineers, to select the optimum mixture combinations that fits best their needs or type of applications, and predict their effects on the concrete performance in the field.

Ghanem, Hassan A.

2009-05-01T23:59:59.000Z

136

Radionuclide Retention in Concrete Wasteforms - FY13  

SciTech Connect

Assessing long-term performance of Category 3 waste cement grouts for radionuclide encasement requires knowledge of the radionuclide-cement interactions and mechanisms of retention (i.e., sorption or precipitation); the mechanism of contaminant release; the significance of contaminant release pathways; how wasteform performance is affected by the full range of environmental conditions within the disposal facility; the process of wasteform aging under conditions that are representative of processes occurring in response to changing environmental conditions within the disposal facility; the effect of wasteform aging on chemical, physical, and radiological properties; and the associated impact on contaminant release. This knowledge will enable accurate prediction of radionuclide fate when the wasteforms come in contact with groundwater. Data collected throughout the course of this work will be used to quantify the efficacy of concrete wasteforms, similar to those used in the disposal of low-level waste and mixed low-level waste, for the immobilization of key radionuclides (i.e., uranium, technetium, and iodine). Data collected will also be used to quantify the physical and chemical properties of the concrete affecting radionuclide retention.

Snyder, Michelle MV; Golovich, Elizabeth C.; Wellman, Dawn M.; Crum, Jarrod V.; Lapierre, Robert; Dage, Denomy C.; Parker, Kent E.; Cordova, Elsa A.

2013-10-15T23:59:59.000Z

137

Electropositive bivalent metallic ion unsaturated polyester complexed polymer concrete  

DOE Patents (OSTI)

Quick setting polymer concrete compositions which are mixtures of unsaturated polyesters and crosslinking monomers together with appropriate initiators and promoters in association with aggregate which may be wet and a source of bivalent metallic ions which will set to polymer concrete with excellent structural properties.

Sugama, T.; Kukacka, L.E.; Horn, W.H.

1981-11-04T23:59:59.000Z

138

Electropositive bivalent metallic ion unsaturated polyester complexed polymer concrete  

DOE Patents (OSTI)

Quick setting polymer concrete compositions with excellent structural properties are disclosed; these polymer concrete compositions are mixtures of unsaturated polyesters and crosslinking monomers together with appropriate initiators and promoters in association with aggregate, which may be wet, and with a source of bivalent metallic ions.

Sugama, Toshifumi (Mastic Beach, NY); Kukacka, Lawrence E. (Port Jefferson, NY); Horn, William H. (Brookhaven, NY)

1985-01-01T23:59:59.000Z

139

An approach for modelling concrete spalling in finite strains  

Science Conference Proceedings (OSTI)

A new approach for modelling concrete spalling process is here proposed, taking into account a fully nonlinear-displacement/strain theory able to catch complex interactions between pressure, thermal and mechanical fields. The micro-structural modelling ... Keywords: Concrete spalling, Finite strains, Micro-structural modelling

C. E. Majorana; V. A. Salomoni; G. Mazzucco; G. A. Khoury

2010-04-01T23:59:59.000Z

140

Concrete decontamination by electro-hydraulic scabbling (EHS). Final report  

SciTech Connect

Contamination of concrete structures by radionuclides, hazardous metals and organic substances (including PCB`s) occurs at many DOE sites. The contamination of concrete structures (walls, floors, ceilings, etc.) varies in type, concentration, and especially depth of penetration into the concrete. In many instances, only the surface layer of concrete is contaminated, up to a depth of one inch, according to estimates provided in the R and D ID document. Then, removal of the concrete surface layer (scabbling) is considered to be the most effective decontamination method. Textron Systems Corp. (TSC) has developed a scabbling concept based on electro-mechanical phenomena accompanying strong electric pulses generated by applying high voltage at the concrete/water interface. Depending on the conditions, the electric discharge may occur either through a waste layer or through the concrete body itself. This report describes the development, testing, and results of this electro-mechanical process. Phase 1 demonstrated the feasibility of the process for the controlled removal of a thin layer of contaminated concrete. Phase 2 designed, fabricated, and tested an integrated subscale unit. This was tested at Fernald. In Phase 3, the scabbling unit was reconfigured to increase its power and processing rate. Technology transfer to an engineering contracting company is continuing.

NONE

1997-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "rectangular precast concrete" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Electropositive bivalent metallic ion unsaturated polyester complexed polymer concrete  

DOE Patents (OSTI)

Quick setting polymer concrete compositions are described which are mixtures of unsaturated polyesters and crosslinking monomers together with appropriate initiators and promoters in association with aggregate which may be wet and a source of bivalent metallic ions which will set to polymer concrete with excellent structural properties.

Sugama, T.; Kukacka, L.E.; Horn, W.H.

1983-05-13T23:59:59.000Z

142

Method for incorporating radioactive phosphoric acid solutions in concrete  

DOE Patents (OSTI)

A method for incorporating radioactive phosphoric acid solutions in concrete is described wherein the phosphoric acid is reacted with Ca(OH)/sub 2/ to form a precipitate of hydroxyapatite and the hydroxyapatite is mixed with Portland cement to form concrete.

Wolf, G.A.; Smith, J.W.; Ihle, N.C.

1982-07-08T23:59:59.000Z

143

Concrete Characterization and Dose Modeling During Plant Decommissioning  

Science Conference Proceedings (OSTI)

Several U.S. nuclear power plants entered decommissioning in the 1990's. The cost effective characterization of contaminated concrete remains a challenge for plants currently undergoing decommissioning. This report provides detailed information on projects involving the characterization, dose modeling, remediation and disposal of contaminated concrete at a number of plants undergoing decommissioning.

2008-03-31T23:59:59.000Z

144

Method for incorporating radioactive phosphoric acid solutions in concrete  

DOE Patents (OSTI)

A method for incorporating radioactive phosphoric acid solutions in concrete is described wherein the phosphoric acid is reacted with Ca(OH).sub.2 to form a precipitate of hydroxyapatite and the hydroxyapatite is mixed with portland cement to form concrete.

Wolf, Gary A. (Kennewick, WA); Smith, Jeffrey W. (Lancaster, OH); Ihle, Nathan C. (Walla Walla, WA)

1984-01-01T23:59:59.000Z

145

The feasibility of modern technologies for reinforced concrete containment structures of nuclear power plants.  

E-Print Network (OSTI)

??This report explores the requirements for the design and analysis of concrete containment and shows how newer material technologies such as self-consolidating concrete (SCC) and (more)

Czerniewski, Sarah

2009-01-01T23:59:59.000Z

146

Review of Concrete Biodeterioration in Relation to Buried Nuclear Waste  

Science Conference Proceedings (OSTI)

Long-term storage of low level radioactive material in below ground concrete disposal units (DUs) (Saltstone Disposal Facility) is a means of depositing wastes generated from nuclear operations of the U.S. Department of Energy. Based on the currently modeled degradation mechanisms, possible microbial induced effects on the structural integrity of buried low level wastes must be addressed. Previous international efforts related to microbial impacts on concrete structures that house low level radioactive waste showed that microbial activity can play a significant role in the process of concrete degradation and ultimately structural deterioration. This literature review examines the recent research in this field and is focused on specific parameters that are applicable to modeling and prediction of the fate of concrete vaults housing stored wastes and the wastes themselves. Rates of concrete biodegradation vary with the environmental conditions, illustrating a need to understand the bioavailability of key compounds involved in microbial activity. Specific parameters require pH and osmotic pressure to be within a certain range to allow for microbial growth as well as the availability and abundance of energy sources like components involved in sulfur, iron and nitrogen oxidation. Carbon flow and availability are also factors to consider in predicting concrete biodegradation. The results of this review suggest that microbial activity in Saltstone, (grouted low level radioactive waste) is unlikely due to very high pH and osmotic pressure. Biodegradation of the concrete vaults housing the radioactive waste however, is a possibility. The rate and degree of concrete biodegradation is dependent on numerous physical, chemical and biological parameters. Results from this review point to parameters to focus on for modeling activities and also, possible options for mitigation that would minimize concrete biodegradation. In addition, key chemical components that drive microbial activity on concrete surfaces are discussed.

Turick, C; Berry, C.

2012-10-15T23:59:59.000Z

147

Diamond Shaving of Contaminated Concrete Surfaces  

Science Conference Proceedings (OSTI)

Decommissioning and decontamination of existing facilities presents technological challenges. One major challenge is the removal of surface contamination from concrete floors and walls while eliminating the spread of contamination and volumetric reduction of the waste stream. Numerous methods have been tried with a varying degree of success. Recent technology has made this goal achievable and has been used successfully. This new technology is the Diamond Floor Shaver and Diamond Wall shaver. The Diamond Floor Shaver is a self-propelled, walk behind machine that literally shaves the contaminated concrete surface to specified depths. This is accomplished by using a patented system of 100 dry cutting diamond blades with offset diamond segments that interlock to provide complete shaving of the concrete surface. Grooves are eliminated which allows for a direct frisk reading to analyze results. When attached to an appropriate size vacuum, the dust produced is 100% contained. Dust is collected in drums ready for disposition and disposal. The waste produced in shaving 7,500 square feet at 1/8 inch thickness would fill a single 55 gallon drum. Production is dependent on depth of shaving but averages 100 square feet per hour. The wall shaver uses the same patented diamond drum and blades but is hydraulically driven and is deployed using a robotic arm allowing its operation to be to totally remote. It can reach ceilings as high as 20 feet. Numerous small projects were successfully completed using this technology. Large scale deployment came in 2003. Bluegrass, in conjunction with Bartlett Services, deployed this technology to support decontamination activities for closing of the Rocky Flats nuclear weapons site. Up to six floor shavers and one wall shaver were deployed in buildings B371 and B374. These buildings had up to one half-inch, fixed plutonium and beryllium contamination. Hundred-thousands of square feet of floors and walls were shaved successfully to depths of up to one half inch. Decontamination efforts were so successful the balance of the buildings could be demolished using conventional methods. The shavers helped keep the project on schedule while the vacuum system eliminated the potential for contaminants becoming airborne.

Mullen, Lisa K. [Bluegrass Concrete Cutting Inc., 107 Mildred Street PO Box 427, Greenville, Alabama 36037 (United States)

2008-01-15T23:59:59.000Z

148

Sulfate and acid resistant concrete and mortar  

DOE Patents (OSTI)

The present invention relates to concrete, mortar and other hardenable mixtures comprising cement and fly ash for use in construction and other applications, which hardenable mixtures demonstrate significant levels of acid and sulfate resistance while maintaining acceptable compressive strength properties. The acid and sulfate hardenable mixtures of the invention containing fly ash comprise cementitious materials and a fine aggregate. The cementitous materials may comprise fly ash as well as cement. The fine aggregate may comprise fly ash as well as sand. The total amount of fly ash in the hardenable mixture ranges from about 60% to about 120% of the total amount of cement, by weight, whether the fly ash is included as a cementious material, fine aggregate, or an additive, or any combination of the foregoing. In specific examples, mortar containing 50% fly ash and 50% cement in cementitious materials demonstrated superior properties of corrosion resistance. 6 figs.

Liskowitz, J.W.; Wecharatana, M.; Jaturapitakkul, C.; Cerkanowicz, A.E.

1998-06-30T23:59:59.000Z

149

Sulfate and acid resistant concrete and mortar  

DOE Patents (OSTI)

The present invention relates to concrete, mortar and other hardenable mixtures comprising cement and fly ash for use in construction and other applications, which hardenable mixtures demonstrate significant levels of acid and sulfate resistance while maintaining acceptable compressive strength properties. The acid and sulfate hardenable mixtures of the invention containing fly ash comprise cementitious materials and a fine aggregate. The cementitous materials may comprise fly ash as well as cement. The fine aggregate may comprise fly ash as well as sand. The total amount of fly ash in the hardenable mixture ranges from about 60% to about 120% of the total amount of cement, by weight, whether the fly ash is included as a cementious material, fine aggregate, or an additive, or any combination of the foregoing. In specific examples, mortar containing 50% fly ash and 50% cement in cementitious materials demonstrated superior properties of corrosion resistance.

Liskowitz, John W. (Belle Mead, NJ); Wecharatana, Methi (Parsippany, NJ); Jaturapitakkul, Chai (Bangkok, TH); Cerkanowicz, deceased, Anthony E. (late of Livingston, NJ)

1998-01-01T23:59:59.000Z

150

Ductility of lightly reinforced concrete hydraulic structures  

E-Print Network (OSTI)

In the past, intake towers built by the Corp of Engineers were designed without consideration of seismic effects. This study investigates an economic approach to determining the ductility of an existing lightly reinforced concrete hydraulic structure. An intake tower, typical of older structure, with reinforcing steel ratios below code specified minimums was selected and modeled using DRAIN-2DX, a dynamic analysis program for personal computers which incorporates the effects of inelastic deformation. The analyses, performed with three separate earthquake acceleration time histories for various model conditions, produced a range of ductility values. The results indicate that ductility is facilitated by the presence of in-plane walls. However, the calculated ductility values may be exaggerated due to the elastic panel elements in the model which redistribute loads away from yielded sections. Also, larger ductility values were calculated for reservoirs with water than for empty reservoirs.

Raines, Amy Lynette

1994-01-01T23:59:59.000Z

151

Concrete Industry Benefits from Ancient Romans and the ALS  

NLE Websites -- All DOE Office Websites (Extended Search)

Concrete Industry Benefits from Concrete Industry Benefits from Ancient Romans and the ALS Concrete Industry Benefits from Ancient Romans and the ALS Print Thursday, 17 October 2013 14:24 Cement production - the mainstay of the modern concrete industry - is one of the primary sources of carbon dioxide emissions worldwide. Making cement essentially requires burning rock, an extremely energy-intensive process that releases a large amount of carbon into the atmosphere. In an effort to reduce its carbon footprint, the industry has begun to move toward new concrete "recipes" that incorporate environmentally friendly supplemental cementitious materials (SCMs), which partially replace Portland cement and reduce its use. The challenge is to maintain, or even increase, the end product's strength and durability while becoming more environmentally sustainable. Ancient Rome, without the impetus of modern environmental concerns, had a lot of this figured out. New insights into the Romans' ingenious concrete harbor structures now emerging from ALS beamline research could move the modern concrete industry toward its goal.

152

Concrete Industry Benefits from Ancient Romans and the ALS  

NLE Websites -- All DOE Office Websites (Extended Search)

Concrete Industry Benefits from Concrete Industry Benefits from Ancient Romans and the ALS Concrete Industry Benefits from Ancient Romans and the ALS Print Thursday, 17 October 2013 14:24 Cement production - the mainstay of the modern concrete industry - is one of the primary sources of carbon dioxide emissions worldwide. Making cement essentially requires burning rock, an extremely energy-intensive process that releases a large amount of carbon into the atmosphere. In an effort to reduce its carbon footprint, the industry has begun to move toward new concrete "recipes" that incorporate environmentally friendly supplemental cementitious materials (SCMs), which partially replace Portland cement and reduce its use. The challenge is to maintain, or even increase, the end product's strength and durability while becoming more environmentally sustainable. Ancient Rome, without the impetus of modern environmental concerns, had a lot of this figured out. New insights into the Romans' ingenious concrete harbor structures now emerging from ALS beamline research could move the modern concrete industry toward its goal.

153

Effect of Concrete Wasteform Properties on Radionuclide Migration  

SciTech Connect

The objective of this investigation was to initiate numerous sets of concrete-soil half-cell tests to quantify 1) diffusion of I and Tc from concrete into uncontaminated soil after 1 and 2 years, 2) I and Re (set 1) and Tc (set 2) diffusion from fractured concrete into uncontaminated soil, and 3) evaluate the moisture distribution profile within the sediment half-cell. These half-cells will be section in FY2009 and FY2010. Additionally, 1) concrete-soil half-cells initiated during FY2007 using fractured prepared with and without metallic iron, half of which were carbonated using carbonated, were sectioned to evaluate the diffusion of I and Re in the concrete part of the half-cell under unsaturated conditions (4%, 7%, and 15% by wt moisture content), 2) concrete-soil half cells containing Tc were sectioned to measure the diffusion profile in the soil half-cell unsaturated conditions (4%, 7%, and 15% by wt moisture content), and 3) solubility measurements of uranium solid phases were completed under concrete porewater conditions. The results of these tests are presented.

Wellman, Dawn M.; Bovaird, Chase C.; Mattigod, Shas V.; Parker, Kent E.; Ermi, Ruby M.; Wood, Marcus I.

2008-09-30T23:59:59.000Z

154

Interaction of hot solid core debris with concrete  

SciTech Connect

The Hot Solid program is intended to measure, model, and assess the thermal, gas evolution, and fission product source terms produced as a consequence of hot, solid, core debris-concrete interactions. Two preliminary experiments, HSS-1 and HSS-3, were performed in order to compare hot solid UO/sub 2/-concrete and hot solid steel-concrete interactions. The HSS-1 experiment ablated 6 cm of limestone-common sand concrete in a little more than three hours using a 9 kg slug of 304 stainless steel at an average debris temperature of 1350/sup 0/C. The HSS-3 experiment ablated 6.5 cm of limestone-common sand concrete in four hours using a 10 kg slug of 80% UO/sub 2/-20% ZrO/sub 2/ at an average debris temperature of 1650/sup 0/C. Both experiments were inductively heated and contained in a 22 cm alumina sleeve to simulate one-dimensional axial erosion. The HOTROX computer code model was evaluated using the results from the HSS tests. HOTROX is a 1-D concrete ablation model that calculates transient conduction and gas release in the concrete as well as heatup of the hot solid slug. Using the HSS-1 power input history and geometry, HOTROX calculates 6.2 cm of concrete erosion in 200 minutes. Using the HSS-3 input conditions, HOTROX predicts 6.8 cm of erosion in 190 minutes. These results compare favorably with the experimental erosion rates. The calculated thermal response of the concrete is also close to experimentally measured values. The information from the Hot Solid Program will be used both to expand the post-accident phenomena data base and to extend the range of applicability of current accident analysis computer models such as CORCON and CONTAIN.

Copus, E.R.; Bradley, D.R.

1986-06-01T23:59:59.000Z

155

Effect of Aggregate Specification in Heavy Concrete for Fusion Reactor Shield on Neutron Dose Evaluation  

E-Print Network (OSTI)

Effect of Aggregate Specification in Heavy Concrete for Fusion Reactor Shield on Neutron Dose Evaluation

Murata, I; Takahashi, A

2000-01-01T23:59:59.000Z

156

Spontaneous Emission from a Two-Level Atom in a Rectangular Waveguide  

E-Print Network (OSTI)

Quantum mechanical treatment of light inside dielectric media is important to understand the behavior of an optical system. In this paper, a two-level atom embedded in a rectangular waveguide surrounded by a perfect electric conductor is considered. Spontaneous emission, propagation, and detection of a photon are described by the second quantization formalism. The quantized modes for light are divided into two types: photonic propagating modes and localized modes with exponential decay along the direction of waveguide. Though spontaneous emission depends on all possible modes including the localized modes, detection far from the source only depends on the propagating modes. This discrepancy of dynamical behaviors gives two di?erent decay rates along space and time in the correlation function of the photon detection.

Moochan B. Kim; Georgios Veronis; Tae-Woo Lee; Hwang Lee; Jonathan P. Dowling

2013-09-20T23:59:59.000Z

157

Two-phase flow characteristics across sudden contraction in small rectangular channels  

SciTech Connect

This study examines the two-phase flow pattern change and pressure drop at the sudden contraction from small rectangular channels (3 x 9 mm and 3 x 6 mm) into a 3 mm diameter tube. A unique deflection of contraction pressure drop vs. vapor quality is observed at a very low quality regime with an unusual ''liquid like vena contracta''. The measured pressure drops are compared with existing correlations/models, but none of them can accurately predict the available database. By proposing a correction factor accounting for the influence of surface tension (Bond number and contraction ratio) to the original homogeneous model, considerable improvement of the predictive ability of homogeneous model is arrived. The mean deviation of this correlation is 26.18% applicable to the present data (80 points) and available literatures (357 points). (author)

Chen, Ing Youn; Chu, Mon-Chern [Mechanical Engineering Department, National Yunlin University of Science and Technology, Yunlin 640 (China); Liaw, Jane-Sunn; Wang, Chi-Chuan [Energy and Environment Research Laboratories, Industrial Technology Research Institute, Hsinchu 310 (China)

2008-09-15T23:59:59.000Z

158

Degree of mixing downstream of rectangular bends and design of an inlet for ambient aerosol  

E-Print Network (OSTI)

Tests were conducted to characterize mixing in a square and a rectangular duct with respect to suitability for single point sampling of contaminants. Several configurations, such as a straight duct with unidirectional flow at the entrance section and straight ducts preceded by mixing elements (a 90° mitred bend, double 90° bends in S- and U-type configurations) were tested. For a straight duct of square cross section, the COV of tracer gas concentration at 19 duct diameters downstream of the gas release location is 143% (Center release). COVs of velocity and tracer gas concentration downstream of each mixing element in square duct setups were verified throughout this study. In the case of a rectangular duct with a 3:1 (width to height) aspect ratio, COVs of velocity and tracer gas concentration only downstream of a 90° mitred bend were verified. Tests were conducted to develop improved inlets for a Battelle bioaerosol sampling system. New inlets have been developed called the All Weather Inlets (AWI), which are designed to prevent entry of precipitation while maintaining aerosol penetration. The AWI has two inlets - one that samples at a flow rate of 780 L/min and the other one that is operated at a flow rate of 90 L/min. The initial version of the AWI-780 L/min unit featured an internal cone, which was removed because the penetration of the AWI-780 without the bottom chamber was higher than that of the Battelle inlet ? 81% with the cone while 86% without the cone for around 9.5 µm AD at 2 km/h. The best bug-screen configuration was verified and a cutpoint management process was performed. The inlets were tested with different wind speeds from 2 to 24 km/h to verify the wind sensitivity of those inlets.

Seo, Youngjin

2004-12-01T23:59:59.000Z

159

Compressive strength of concrete and mortar containing fly ash  

DOE Patents (OSTI)

The present invention relates to concrete, mortar and other hardenable mixtures comprising cement and fly ash for use in construction. The invention includes a method for predicting the compressive strength of such a hardenable mixture, which is very important for planning a project. The invention also relates to hardenable mixtures comprising cement and fly ash which can achieve greater compressive strength than hardenable mixtures containing only concrete over the time period relevant for construction. In a specific embodiment, a formula is provided that accurately predicts compressive strength of concrete containing fly ash out to 180 days. In other specific examples, concrete and mortar containing about 15% to 25% fly ash as a replacement for cement, which are capable of meeting design specifications required for building and highway construction, are provided. Such materials can thus significantly reduce construction costs.

Liskowitz, John W. (Belle Mead, NJ); Wecharatana, Methi (Parsippany, NJ); Jaturapitakkul, Chai (Bangkok, TH); Cerkanowicz, deceased, Anthony E. (late of Livingston, NJ)

1997-01-01T23:59:59.000Z

160

Compressive strength of concrete and mortar containing fly ash  

DOE Patents (OSTI)

The present invention relates to concrete, mortar and other hardenable mixtures comprising cement and fly ash for use in construction. The invention includes a method for predicting the compressive strength of such a hardenable mixture, which is very important for planning a project. The invention also relates to hardenable mixtures comprising cement and fly ash which can achieve greater compressive strength than hardenable mixtures containing only concrete over the time period relevant for construction. In a specific embodiment, a formula is provided that accurately predicts compressive strength of concrete containing fly ash out to 180 days. In other specific examples, concrete and mortar containing about 15% to 25% fly ash as a replacement for cement, which are capable of meeting design specification required for building and highway construction, are provided. Such materials can thus significantly reduce construction costs. 33 figs.

Liskowitz, J.W.; Wecharatana, M.; Jaturapitakkul, C.; Cerkanowicz, A.E.

1998-12-29T23:59:59.000Z

Note: This page contains sample records for the topic "rectangular precast concrete" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Compressive strength of concrete and mortar containing fly ash  

DOE Patents (OSTI)

The present invention relates to concrete, mortar and other hardenable mixtures comprising cement and fly ash for use in construction. The invention includes a method for predicting the compressive strength of such a hardenable mixture, which is very important for planning a project. The invention also relates to hardenable mixtures comprising cement and fly ash which can achieve greater compressive strength than hardenable mixtures containing only concrete over the time period relevant for construction. In a specific embodiment, a formula is provided that accurately predicts compressive strength of concrete containing fly ash out to 180 days. In other specific examples, concrete and mortar containing about 15% to 25% fly ash as a replacement for cement, which are capable of meeting design specification required for building and highway construction, are provided. Such materials can thus significantly reduce construction costs.

Liskowitz, John W. (Belle Mead, NJ); Wecharatana, Methi (Parsippany, NJ); Jaturapitakkul, Chai (Bangkok, TH); Cerkanowicz, deceased, Anthony E. (late of Livingston, NJ)

1998-01-01T23:59:59.000Z

162

Compressive strength of concrete and mortar containing fly ash  

DOE Patents (OSTI)

The present invention relates to concrete, mortar and other hardenable mixtures comprising cement and fly ash for use in construction. The invention includes a method for predicting the compressive strength of such a hardenable mixture, which is very important for planning a project. The invention also relates to hardenable mixtures comprising cement and fly ash which can achieve greater compressive strength than hardenable mixtures containing only concrete over the time period relevant for construction. In a specific embodiment, a formula is provided that accurately predicts compressive strength of concrete containing fly ash out to 180 days. In other specific examples, concrete and mortar containing about 15% to 25% fly ash as a replacement for cement, which are capable of meeting design specifications required for building and highway construction, are provided. Such materials can thus significantly reduce construction costs. 33 figs.

Liskowitz, J.W.; Wecharatana, M.; Jaturapitakkul, C.; Cerkanowicz, A.E.

1997-04-29T23:59:59.000Z

163

Viscosity Modifiers to Enhance Concrete Performance Dale P. ...  

Science Conference Proceedings (OSTI)

... For the concrete, the LWA sand (an expanded shale) had a pre-wetted specific gravity of 1.7, an absorption of 25 % by dry mass, and a ...

2011-12-09T23:59:59.000Z

164

The Complexity of Reasoning with Concrete Domains Revised Version  

Science Conference Proceedings (OSTI)

Description logics are knowledge representation and reasoning formalisms which represent conceptual knowledge on an abstract logical level. Concrete domains are a theoretically well-founded approach to the integration of description logic reasoning with ...

C. Lutz

1999-08-01T23:59:59.000Z

165

Life cycle assessment of concrete pavements : impacts and opportunities  

E-Print Network (OSTI)

The concrete pavement network in the United States plays a crucial role in the economy by enabling the transport of people and goods, but it also leads to resource consumption and environmental impacts. This thesis is ...

Loijos, Alex (Alexander Nikos)

2011-01-01T23:59:59.000Z

166

Design of wind turbines with Ultra-High Performance Concrete  

E-Print Network (OSTI)

Ultra-High Performance Concrete (UHPC) has proven an asset for bridge design as it significantly reduces costs. However, UHPC has not been applied yet to wind turbine technology. Design codes do not propose any recommendations ...

Jammes, Franois-Xavier

2009-01-01T23:59:59.000Z

167

Dynamic analysis of concrete coupled wall structures : a parametric study  

E-Print Network (OSTI)

Concrete coupled wall structure is a system that can efficiently dissipate energy under the effect of lateral loads. It has been widely used in medium height buildings for several decades. While researchers have conducted ...

Huang, Elaine Annabelle, 1981-

2005-01-01T23:59:59.000Z

168

Centrifuge Modeling and Analysis of Concrete Gravity Dams  

Science Conference Proceedings (OSTI)

This report contains general background information on centrifuge experimentation and linear elastic fracture mechanics pertaining to concrete gravity dam models, and explains in detail the experimental methodology and procedures developed for testing concrete gravity dam models in centrifuges. An important detail in the experimental procedure is that the models are loaded upstream with water and, at fracture, have water uplift pressure within any cracks. Finally, test results and comparisons to analytic...

1995-12-14T23:59:59.000Z

169

Identification of Concrete Incompatibilities Using Cement Paste Rheology  

E-Print Network (OSTI)

The complex interaction between cement and chemical/mineral admixtures in concrete mixtures sometimes leads to unpredictable concrete performance in the field which is generally defined as concrete incompatibilities. Cement paste rheology measurements instead of traditional workability tests (i.e., slump cone test) can have great potential in detecting those incompatibilities in concrete before the concrete is placed, which can, in turn, avoid related workability problems and setting time as well as heat evolution abnormalities. The objectives of the present study were to examine the applicability of the dynamic shear rheometer (DSR) to measure cement paste rheology, and to identify cement and mineral/chemical admixture incompatibilities, based on the determined rheological parameters. The DSR was modified and optimized for cement paste rheology measurements. Two different modes of operations (i.e., static and dynamic methods) with the modified DSR were investigated to measure representative rheological parameters as well as to identify cement and chemical/mineral admixture incompatibility. The conventional plastic viscosity and yield stress are measured in static mode and storage modulus curve, as a function of time, is measured in dynamic mode. The rate of change of plastic viscosity (RPV) as another static rheological parameter and the modeled magnitude parameter ?, from the dynamic rheological method, showed great potentialities as acceptance criteria to identify incompatible mixtures. The heat of hydration data from isothermal conduction calorimeter tests and setting time results for the studied mixtures have strongly supported the rheology based observations as supporting tools. Based on the main tests results, the acceptance criteria were set up using the rheological parameters in accordance with heat of hydration data. This will ultimately help material suppliers, concrete producers, and other users to detect problematic combinations of concrete ingredients before a given concrete mixture is placed.

Jang, Se Hoon

2009-05-01T23:59:59.000Z

170

Program on Technology Innovation: Nuclear Concrete Structures Aging Reference Manual  

Science Conference Proceedings (OSTI)

EPRI has been proactive in researching concrete degradation in nuclear plants in recent years, with a focus on anticipated future regulatory mandates regarding relicensing beyond 60 years operation (long-term operation). The comprehensive treatment of concrete degradation provided in this report will be used to guide research and development activities. EPRI is currently working to address such issues to benefit the industry and will continue to do so.

2011-10-14T23:59:59.000Z

171

Modeling of Molten Core Concrete Interactions and Fission Product Release  

Science Conference Proceedings (OSTI)

The study of molten core concrete interactions is important in estimating the possible consequences of a severe nuclear reactor accident. CORCON-Mod2 is a computer program that models the thermal, chemical, and physical phenomena associated with molten core concrete interactions. Models have been added to extend the modeling of these phenomena. An ideal solution chemical equilibrium methodology predicts the fission product vaporization release. Additional chemical species have been added, and the calcula...

1994-05-27T23:59:59.000Z

172

Effect of Concrete Waste Form Properties on Radionuclide Migration  

Science Conference Proceedings (OSTI)

Assessing long-term performance of Category 3 waste cement grouts for radionuclide encasement requires knowledge of the radionuclide-cement interactions and mechanisms of retention (i.e., sorption or precipitation) the mechanism of contaminant release, the significance of contaminant release pathways, how waste form performance is affected by the full range of environmental conditions within the disposal facility, the process of waste form aging under conditions that are representative of processes occurring in response to changing environmental conditions within the disposal facility, the effect of waste form aging on chemical, physical, and radiological properties and the associated impact on contaminant release. This knowledge will enable accurate prediction of radionuclide fate when the waste forms come in contact with groundwater. Numerous sets of tests were initiated in fiscal years (FY) 2006-2009 to evaluate (1) diffusion of iodine (I) and technetium (Tc) from concrete into uncontaminated soil after 1 and 2 years, (2) I and rhenium (Re) diffusion from contaminated soil into fractured concrete, (3) I and Re (set 1) and Tc (set 2) diffusion from fractured concrete into uncontaminated soil, (4) evaluate the moisture distribution profile within the sediment half-cell, (5) the reactivity and speciation of uranium (VI) (U(VI)) compounds in concrete porewaters, (6) the rate of dissolution of concrete monoliths, and (7) the diffusion of simulated tank waste into concrete.

Mattigod, Shas V.; Bovaird, Chase C.; Wellman, Dawn M.; Skinner, De'Chauna J.; Cordova, Elsa A.; Wood, Marcus I.

2009-09-30T23:59:59.000Z

173

Relaxation and Intermediate Asymptotics of a Rectangular Trench in a Viscous Film  

E-Print Network (OSTI)

The surface of a thin liquid film with nonconstant curvature flattens as a result of capillary forces. While this leveling is driven by local curvature gradients, the global boundary conditions greatly influence the dynamics. Here, we study the evolution of rectangular trenches in a polystyrene nanofilm. Initially, when the two sides of a trench are well separated, the asymmetric boundary condition given by the step height controls the dynamics. In this case, the evolution results from the leveling of two noninteracting steps. As the steps broaden further and start to interact, the global symmetric boundary condition alters the leveling dynamics. We report on full agreement between theory and experiments for: the capillary-driven flow and resulting time dependent height profiles; a crossover in the power-law dependence of the viscous energy dissipation as a function of time as the trench evolution transitions from two noninteracting to interacting steps; and the convergence of the profiles to a universal self-similar attractor that is given by the Green's function of the linear operator describing the dimensionless linearized thin film equation.

Oliver Bumchen; Michael Benzaquen; Thomas Salez; Joshua D. McGraw; Matilda Backholm; Paul Fowler; Elie Raphal; Kari Dalnoki-Veress

2013-09-10T23:59:59.000Z

174

Bubble confinement in flow boiling of FC-72 in a ''rectangular'' microchannel of high aspect ratio  

SciTech Connect

Boiling in microchannels remains elusive due to the lack of full understanding of the mechanisms involved. A powerful tool in achieving better comprehension of the mechanisms is detailed imaging and analysis of the two-phase flow at a fundamental level. Boiling is induced in a single microchannel geometry (hydraulic diameter 727 {mu}m), using a refrigerant FC-72, to investigate the effect of channel confinement on bubble growth. A transparent, metallic, conductive deposit has been developed on the exterior of the rectangular microchannel, allowing simultaneous uniform heating and visualisation to be achieved. The data presented in this paper is for a particular case with a uniform heat flux applied to the microchannel and inlet liquid mass flowrate held constant. In conjunction with obtaining high-speed images and videos, sensitive pressure sensors are used to record the pressure drop across the microchannel over time. Bubble nucleation and growth, as well as periodic slug flow, are observed in the microchannel test section. The periodic pressure fluctuations evidenced across the microchannel are caused by the bubble dynamics and instances of vapour blockage during confined bubble growth in the channel. The variation of the aspect ratio and the interface velocities of the growing vapour slug over time, are all observed and analysed. We follow visually the nucleation and subsequent both 'free' and 'confined' growth of a vapour bubble during flow boiling of FC-72 in a microchannel, from analysis of our results, images and video sequences with the corresponding pressure data obtained. (author)

Barber, Jacqueline [School of Engineering, University of Edinburgh, The King's Buildings, Mayfield Road, Edinburgh, EH9 3JL (United Kingdom); Aix-Marseille Universite (UI, UII) - CNRS Laboratoire IUSTI, UMR 6595, 5 Rue Enrico Fermi, Marseille 13453 (France); Brutin, David; Tadrist, Lounes [Aix-Marseille Universite (UI, UII) - CNRS Laboratoire IUSTI, UMR 6595, 5 Rue Enrico Fermi, Marseille 13453 (France); Sefiane, Khellil [School of Engineering, University of Edinburgh, The King's Buildings, Mayfield Road, Edinburgh, EH9 3JL (United Kingdom)

2010-11-15T23:59:59.000Z

175

The analysis of single-electron orbits in a free electron laser based upon a rectangular hybrid wiggler  

SciTech Connect

A three-dimensional analysis of a novel free-electron laser (FEL) based upon a rectangular hybrid wiggler (RHW) is presented. This RHW is designed in a configuration composed of rectangular rings with alternating ferrite and dielectric spacers immersed in a solenoidal magnetic field. An analytic model of RHW is introduced by solution of Laplace's equation for the magnetostatic fields under the appropriate boundary conditions. The single-electron orbits in combined RHW and axial guide magnetic fields are studied when only the first and the third spatial harmonic components of the RHW field are taken into account and the higher order terms are ignored. The results indicate that the third spatial harmonic leads to group III orbits with a strong negative mass regime particularly in large solenoidal magnetic fields. RHW is found to be a promising candidate with favorable characteristics to be used in microwave FEL.

Kordbacheh, A.; Ghahremaninezhad, Roghayeh [Department of Physics, Iran University of Science and Technology, 1684613114 Tehran (Iran, Islamic Republic of); Maraghechi, B. [Department of Physics, Amirkabir University of Technology, 159163411 Tehran (Iran, Islamic Republic of)

2012-09-15T23:59:59.000Z

176

Bayesian prediction of modulus of elasticity of self consolidated concrete  

E-Print Network (OSTI)

Current models of the modulus of elasticity, E , of concrete recommended by the American Concrete Institute (ACI) and the American Association of State Highway and Transportation Officials (AASHTO) are derived only for normally vibrated concrete (NVC). Because self consolidated concrete (SCC) mixtures used today differ from NVC in the quantities and types of constituent materials, mineral additives, and chemical admixtures, the current models may not take into consideration the complexity of SCC, and thus they may predict the E of SCC inaccurately. Although some authors recommend specific models to predict the E of SCC, they include only a single variable of assumed importance, namely the compressive strength of concrete, c f ? . However there are other parameters that may need to be accounted for while developing a prediction model for the E of SCC. In this research, a Bayesian variable selection method is implemented to identify the significant parameters in predicting the E of SCC and more accurate models for the E are generated using these variables. The models have a parsimonious parameterization for ease of use in practice and properly account for the prevailing uncertainties.

Bhattacharjee, Chandan

2007-12-01T23:59:59.000Z

177

Report on aging of nuclear power plant reinforced concrete structures  

Science Conference Proceedings (OSTI)

The Structural Aging Program provides the US Nuclear Regulatory Commission with potential structural safety issues and acceptance criteria for use in continued service assessments of nuclear power plant safety-related concrete structures. The program was organized under four task areas: Program Management, Materials Property Data Base, Structural Component Assessment/Repair Technology, and Quantitative Methodology for Continued Service Determinations. Under these tasks, over 90 papers and reports were prepared addressing pertinent aspects associated with aging management of nuclear power plant reinforced concrete structures. Contained in this report is a summary of program results in the form of information related to longevity of nuclear power plant reinforced concrete structures, a Structural Materials Information Center presenting data and information on the time variation of concrete materials under the influence of environmental stressors and aging factors, in-service inspection and condition assessments techniques, repair materials and methods, evaluation of nuclear power plant reinforced concrete structures, and a reliability-based methodology for current and future condition assessments. Recommendations for future activities are also provided. 308 refs., 61 figs., 50 tabs.

Naus, D.J.; Oland, C.B. [Oak Ridge National Lab., TN (United States); Ellingwood, B.R. [Johns Hopkins Univ., Baltimore, MD (United States). Dept. of Civil Engineering

1996-03-01T23:59:59.000Z

178

The time optimal control problem with control constraints of the rectangular type for a class of ODEs  

E-Print Network (OSTI)

This paper studies a time optimal control problem with control constraints of the rectangular type for the linear multi-input time-varying ordinary di?erential equations. The aims of this study are to establish certain necessary and sufficient conditions for the optimal time and time optimal control, and to build up an al- gorithm for the optimal time and time optimal control.

Zhang, Can

2011-01-01T23:59:59.000Z

179

Nondestructive Evaluation of Concrete Structures at BAM | ornl.gov  

NLE Websites -- All DOE Office Websites (Extended Search)

Nondestructive Evaluation of Concrete Structures at BAM Nondestructive Evaluation of Concrete Structures at BAM Jan 17 2014 10:00 AM - 11:00 AM Dr. Herbert Wiggenhauser, Federal Institute for Materials Research and Testing (BAM), Berlin, Germany EESRD Seminar Weinberg Auditorium CONTACT : Email: Dwight Clayton Phone:865.576.8134 Add to Calendar SHARE NDT of concrete structures at BAM (Federal Institute for Materials Research and Testing) in Berlin/Germany is focussed on the evaluation of structural properties in RC structures: Location of reinforcement, position of tendon ducts, condition of grouting in tendons, presence and location of honeycombs, sizing of cracks and others. These testing tasks are mainly solved using GPR (ground penetrating radar) and low frequency ultrasound pulse echo. Scanning and automation supports the evaluations and

180

Transient analysis of LMFBR reinforced/prestressed concrete containment  

SciTech Connect

The use of prestressed concrete reactor vessels (PCRVs) for LMFBR containment creates a need for analytical methods for treating the transient response of such structures, for LMFBR containment must be capable of sustaining the dynamic effects which arise in a hypothetical core disruptive accident (HCDA). These analyses require several unique features: a model of concrete which includes tensile cracking, a methodology for representing the prestressing tendons and for simulating the prestressing operation, and an efficient computational tool for treating the transient response. For the purpose of treating the transient response, a finite element program with explicit time integration was chosen. For the purpose of illustrating the applicability of these techniques and the validity of the models for concrete and the prestressing tendons, several example solutions are presented and compared with experimental results.

Marchertas, A.H.; Belytschko, T.B.; Bazant, Z.P.

1979-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "rectangular precast concrete" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Treatment of fly ash for use in concrete  

DOE Patents (OSTI)

A process for treating fly ash to render it highly usable as a concrete additive. A quantity of fly ash is obtained that contains carbon and which is considered unusable fly ash for concrete based upon foam index testing. The fly ash is mixed with an activator solution sufficient to initiate a geopolymerization reaction and for a geopolymerized fly ash. The geopolymerized fly ash is granulated. The geopolymerized fly ash is considered usable fly ash for concrete according to foam index testing. The geopolymerized fly ash may have a foam index less than 35% of the foam index of the untreated fly ash, and in some cases less than 10% of the foam index of the untreated fly ash. The activator solution may contain an alkali metal hydroxide, carbonate, silicate, aluminate, or mixtures thereof.

Boxley, Chett (Park City, UT); Akash, Akash (Salt lake City, UT); Zhao, Qiang (Natick, MA)

2012-05-08T23:59:59.000Z

182

Treatment of fly ash for use in concrete  

DOE Patents (OSTI)

A process for treating fly ash to render it highly usable as a concrete additive. A quantity of fly ash is obtained that contains carbon and which is considered unusable fly ash for concrete based upon foam index testing. The fly ash is mixed with an activator solution sufficient to initiate a geopolymerization reaction and for a geopolymerized fly ash. The geopolymerized fly ash is granulated. The geopolymerized fly ash is considered usable fly ash for concrete according to foam index testing. The geopolymerized fly ash may have a foam index less than 35% of the foam index of the untreated fly ash, and in some cases less than 10% of the foam index of the untreated fly ash. The activator solution may contain an alkali metal hydroxide, carbonate, silicate, aluminate, or mixtures thereof.

Boxley, Chett; Akash, Akash; Zhao, Qiang

2013-01-08T23:59:59.000Z

183

Treatment of fly ash for use in concrete  

DOE Patents (OSTI)

A process for treating fly ash to render it highly usable as a concrete additive. A quantity of fly ash is obtained that contains carbon and which is considered unusable fly ash for concrete based upon foam index testing. The fly ash is mixed with a quantity of spray dryer ash (SDA) and water to initiate a geopolymerization reaction and form a geopolymerized fly ash. The geopolymerized fly ash is granulated. The geopolymerized fly ash is considered usable fly ash for concrete according to foam index testing. The geopolymerized fly ash may have a foam index less than 40%, and in some cases less than 20%, of the foam index of the untreated fly ash. An optional alkaline activator may be mixed with the fly ash and SDA to facilitate the geopolymerization reaction. The alkaline activator may contain an alkali metal hydroxide, carbonate, silicate, aluminate, or mixtures thereof.

Boxley, Chett (Park City, UT)

2012-05-15T23:59:59.000Z

184

TEST METHOD FOR COEFFICIENT OF LINEAR THERMAL EXPANSION OF CONCRETE  

E-Print Network (OSTI)

1.1 This method covers the determination of the coefficient of linear thermal expansion of concrete test specimens by determinations of length change due to temperature changes. Because the thermal coefficient of concrete varies with moisture condition, being a minimum when saturated or oven dry and a maximum at about 70 percent saturated, it is important to select the relevant moisture condition for the tests to be made. 2. Apparatus 2.1. The apparatus shall consist of: 2.1.1 Heating Bath- A water bath in which concrete specimens can be maintained at a temperature of 140 2 F (60 1.1 C) (Note 1) 2.1.2 Cooling Bath- A water bath in which

unknown authors

1981-01-01T23:59:59.000Z

185

Light Water Reactor Sustainability Nondestructive Evaluation for Concrete  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Nondestructive Evaluation for Nondestructive Evaluation for Concrete Research and Development Roadmap Light Water Reactor Sustainability Nondestructive Evaluation for Concrete Research and Development Roadmap Materials issues are a key concern for the existing nuclear reactor fleet as material degradation can lead to increased maintenance, increased downtown, and increased risk. Extending reactor life to 60 years and beyond will likely increase susceptibility and severity of known forms of degradation. Additionally, new mechanisms of materials degradation are also possible. The purpose of the US Department of Energy Office of Nuclear Energy's Light Water Reactor Sustainability (LWRS) Program is to develop technologies and other solutions that can improve the reliability, sustain the safety, and extend

186

Economic assessment of polymer concrete usage in geothermal power plants  

DOE Green Energy (OSTI)

Results of a study established to review the Heber and Niland, California 50 MWe conceptual geothermal power plants designs and to identify areas where non-metallic materials, such as polymer concrete, can be technically and economically employed are reported. Emphasis was directed toward determining potential economic advantages and resulting improvements in plant availability. It is estimated that use of polymer concrete in the Heber plant will effect a savings of 6.18 mills per KWH in the cost of power delivered to the network, a savings of 9.7%. A similar savings should be effected in the Niland plant.

Not Available

1977-11-01T23:59:59.000Z

187

Alternative Fuels Data Center: Ozinga Adds 14 Natural Gas Concrete Mixers  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Ozinga Adds 14 Natural Ozinga Adds 14 Natural Gas Concrete Mixers to Its Fleet to someone by E-mail Share Alternative Fuels Data Center: Ozinga Adds 14 Natural Gas Concrete Mixers to Its Fleet on Facebook Tweet about Alternative Fuels Data Center: Ozinga Adds 14 Natural Gas Concrete Mixers to Its Fleet on Twitter Bookmark Alternative Fuels Data Center: Ozinga Adds 14 Natural Gas Concrete Mixers to Its Fleet on Google Bookmark Alternative Fuels Data Center: Ozinga Adds 14 Natural Gas Concrete Mixers to Its Fleet on Delicious Rank Alternative Fuels Data Center: Ozinga Adds 14 Natural Gas Concrete Mixers to Its Fleet on Digg Find More places to share Alternative Fuels Data Center: Ozinga Adds 14 Natural Gas Concrete Mixers to Its Fleet on AddThis.com... Sept. 28, 2013 Ozinga Adds 14 Natural Gas Concrete Mixers to Its Fleet

188

Lightweight concrete : investigations into the production of variable density cellular materials  

E-Print Network (OSTI)

This research focuses on the intersection between material composition and form in the development of a new type of concrete. As concrete is the most widely used building material in the world, innovation in this material ...

Cooke, Timothy Graham

2012-01-01T23:59:59.000Z

189

The Effect of Elevated Temperature on Concrete Materials and Structures - a Literature Review.  

Science Conference Proceedings (OSTI)

The objective of this limited study was to provide an overview of the effects of elevated temperature on the behavior of concrete materials and structures. In meeting this objective the effects of elevated temperatures on the properties of ordinary Portland cement concrete constituent materials and concretes are summarized. The effects of elevated temperature on high-strength concrete materials are noted and their performance compared to normal strength concretes. A review of concrete materials for elevated-temperature service is presented. Nuclear power plant and general civil engineering design codes are described. Design considerations and analytical techniques for evaluating the response of reinforced concrete structures to elevated-temperature conditions are presented. Pertinent studies in which reinforced concrete structural elements were subjected to elevated temperatures are described.

Naus, Dan J [ORNL

2006-03-01T23:59:59.000Z

190

Seismic Performance, Modeling, and Failure Assessment of Reinforced Concrete Shear Wall Buildings  

E-Print Network (OSTI)

of Structural Engineering, ASCE, V. 117, No. 5, pp. 1514-J. P. , (2007). Update to ASCE/SEI 41 Concrete Provisions.Model for Confined Concrete", ASCE Journal of Structural

Tuna, Zeynep

2012-01-01T23:59:59.000Z

191

Three-dimensional gravity modeling and focusing inversion using rectangular meshes.  

SciTech Connect

Rectangular grid cells are commonly used for the geophysical modeling of gravity anomalies, owing to their flexibility in constructing complex models. The straightforward handling of cubic cells in gravity inversion algorithms allows for a flexible imposition of model regularization constraints, which are generally essential in the inversion of static potential field data. The first part of this paper provides a review of commonly used expressions for calculating the gravity of a right polygonal prism, both for gravity and gradiometry, where the formulas of Plouff and Forsberg are adapted. The formulas can be cast into general forms practical for implementation. In the second part, a weighting scheme for resolution enhancement at depth is presented. Modelling the earth using highly digitized meshes, depth weighting schemes are typically applied to the model objective functional, subject to minimizing the data misfit. The scheme proposed here involves a non-linear conjugate gradient inversion scheme with a weighting function applied to the non-linear conjugate gradient scheme's gradient vector of the objective functional. The low depth resolution due to the quick decay of the gravity kernel functions is counteracted by suppressing the search directions in the parameter space that would lead to near-surface concentrations of gravity anomalies. Further, a density parameter transformation function enabling the imposition of lower and upper bounding constraints is employed. Using synthetic data from models of varying complexity and a field data set, it is demonstrated that, given an adequate depth weighting function, the gravity inversion in the transform space can recover geologically meaningful models requiring a minimum of prior information and user interaction.

Commer, M.

2011-03-01T23:59:59.000Z

192

A Non-Pyramidal Rectangular-to-Trough Waveguide Transition and Pattern Reconfigurable Trough Waveguide Antenna  

E-Print Network (OSTI)

Trough waveguides (TWG) have been utilized in a variety of radio frequency (RF) and other related applications including radar, the treatment of hypothermia and in the generation of plasmas. Perturbing the guided wave in these structures with blocks, rods, dielectrics, and other structures can create reconfigurable periodic line sources. These trough waveguide antennas (TWA) are then capable of providing both fixedfrequency and frequency-dependent beam steering. This was originally performed using electro-mechanical cam-and-gear mechanisms. Previous work related to the excitation of TWG and the performance of TWA topologies are limited when compared to more common antenna designs, yet they possess many desirable features that can be exploited in a modern system. This thesis will examines an S-band rectangular-to-trough waveguide transition and trough guide antenna that has been designed for broadband reconfigurable antenna applications considering as well the airflow characteristics for sensing applications. The design, fabrication, and electromagnetic performance (mode conversion, impedance matching, and antenna performance) are discussed, including the use of metallic cantilever perturbations placed along the troughguide sidewalls that are designed to provide improved impedance matching when steering the beam from the backward quadrant through broadside, towards the forward quadrant. Impedance matching techniques such as use of circular holes at the edge of each actuated cantilever are used to reduce power reflections and provide a low voltage standing wave ratio (VSWR) along the S-band. Finite element simulations will provide a demonstration of the airflow and turbulence characteristics throughout the entire structure, where the metallic cantilevers are used to manipulate the flow of air, to distribute it across the surfaces of the structure better and improve its potential for sensing operations.

Loizou, Loizos

2010-12-01T23:59:59.000Z

193

Mercury Emissions from Curing Concretes that Contain Fly Ash and Activated Carbon Sorbents  

Science Conference Proceedings (OSTI)

This report presents new laboratory data on the release of mercury from concrete containing fly ash and powdered activated carbon sorbents used to capture mercury. The concretes studied in this project were made with fly ashes from lignite and subbituminous coal, including fly ashes containing powdered activated carbon (PAC). Minute quantities of mercury were emitted from five concretes during the standard 28-day curing process and throughout an additional 28 days of curing for two of these concretes. Ge...

2006-09-07T23:59:59.000Z

194

Monitoring the Durability Performance of Concrete in Nuclear Waste Containment. Second technical progress report  

Science Conference Proceedings (OSTI)

OAK-B135 Monitoring the Durability Performance of Concrete in Nuclear Waste Containment. Second technical progress report

Ulm, Franz-Josef

1999-12-31T23:59:59.000Z

195

Advanced Nuclear Technology: Quality Control of Concrete During Construction - Voids Detection  

Science Conference Proceedings (OSTI)

The main type of degradation of concrete structures during the construction of nuclear power plants has been the existence of honeycombs and voids due to inadequate concrete design and placement. The detection of these honeycombs and voids in concrete structures has been attempted with nondestructive evaluation technologies with limited success. The addition of steel-concrete construction techniques further complicates the ability of these technologies to ...

2012-12-22T23:59:59.000Z

196

Measurements of Accelerator-Produced Leakage Neutron and Photon Transmission through Concrete  

DOE Green Energy (OSTI)

Optimum shielding of the radiation from particle accelerators requires knowledge of the attenuation characteristics of the shielding material. The most common material for shielding this radiation is concrete, which can be made using various materials of different densities as aggregates. These different concrete mixes can have very different attenuation characteristics. Information about the attenuation of leakage photons and neutrons in ordinary and heavy concrete is, however, very limited. To increase our knowledge and understanding of the radiation attenuation in concrete of various compositions, we have performed measurements of the transmission of leakage radiation, photons and neutrons, from a Varian Clinac 2100C medical linear accelerator operating at maximum electron energies of 6 and 18 MeV. We also calculated, using Monte Carlo techniques, the leakage neutron spectra and its transmission through concrete. The results of these measurements and calculations extend the information currently available for designing shielding for medical electron accelerators. Photon transmission characteristics depend more on the manufacturer of the concrete than on the atomic composition. A possible cause for this effect is a non-uniform distribution of the high density aggregate, typically iron, in the concrete matrix. Errors in estimated transmission of photons can exceed a factor of three, depending on barrier thickness, if attenuation in high-density concrete is simply scaled from that of normal density concrete. We found that neutron transmission through the high-density concretes can be estimated most reasonably and conservatively by using the linear tenth-value layer of normal concrete if specific values of the tenth-value layer of the high-density concrete are not known. The reason for this is that the neutron transmission depends primarily on the hydrogen content of the concrete, which does not significantly depend on concrete density. Errors of factors of two to more than ten, depending on barrier thickness, in the estimated transmission of neutrons through high-density concrete can be made if the attenuation is scaled by density from normal concrete.

Nelson, Walter R

2002-07-04T23:59:59.000Z

197

Sustainable Concrete with Industrial and Post-Consumer By-Products  

E-Print Network (OSTI)

with recycled-aggregates and fly ash shows no deleterious effect on the durability of reinforced concrete that the addition of residual solids in concrete enhances its durability properties in freezing and thawing(1), 91-100. Sonebi, M. (2004), "Medium strength self-compacting concrete containing fly ash: modeling

Wisconsin-Milwaukee, University of

198

Mechanical properties of self-compacting concrete reinforced with polypropylene fibres  

E-Print Network (OSTI)

and M. M. Hossain: `Abrasion resistance of high-strength concrete made with class C fly ash', ACI Mater, natural pozzolans and fly ash (FA), can be used to increase the viscosity and fresh concrete workability term durability and strength. Mix proportions Ten mixture compositions for each cubic metre of concrete

North Texas, University of

199

Engineered Cementitious Composites (ECC) Bendable Concrete Fracture MechanicsExperiments and Observations  

E-Print Network (OSTI)

and normal concrete Figure 3. Tensile stress-strain behavior of fiber reinforced geopolymer [1] V.C. Li , "On reinforced geopolymer Property Fiber reinforced geopolymer Normal concrete Compressive strength (MPa) 17.4 40Engineered Cementitious Composites (ECC) ­ Bendable Concrete Fracture Mechanics

Li, Victor C.

200

Linseed Oil-Based Concrete Surface Treatment -for Building and Highway Structures in  

E-Print Network (OSTI)

, Linseed Oil-Based Concrete Surface Treatment -for Building and Highway Structures in Hong Kong Y using jour Canadian linseed oil- based sealants on concrete specimens madejrom G30120 and G45120 Keywords: Unseed Oil, Concrete Surface Treatment, Salt Spray Resistance, Carbonation, Bond Strength, Ultra

Note: This page contains sample records for the topic "rectangular precast concrete" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Behaviour of the sustainable fiber reinforced concrete with recycled aggregate after loading  

Science Conference Proceedings (OSTI)

This paper presents an experimental investigation of fiber reinforced concrete made from construction and demolition waste - recycled concrete and masonry aggregate with and without polypropylene fibres. This work was aimed at evaluating physical - mechanical ... Keywords: composite material, ductility, fiber reinforced concrete, fibres, flexural strength, properties, pseudo-working diagram, splitting strength

Vladimira Vytlacilova

2011-11-01T23:59:59.000Z

202

Seismic fracture analysis of concrete gravity dams including dam-reservoir interaction  

Science Conference Proceedings (OSTI)

In this study, the seismic fracture response of concrete gravity dams is investigated with considering the effects of dam-reservoir interaction. A co-axial rotating crack model (CRCM), which includes the strain softening behavior, is selected for concrete ... Keywords: Concrete gravity dam, Dam-reservoir interaction, Non-linear analysis, Seismic fracture

Yusuf Calayir; Muhammet Karaton

2005-07-01T23:59:59.000Z

203

ASSESSMENT OF RELEASE RATES FOR RADIONUCLIDES IN ACTIVATED CONCRETE.  

Science Conference Proceedings (OSTI)

The Maine Yankee (MY) nuclear power plant is undergoing the process of decontamination and decommissioning (D&D). Part of the process requires analyses that demonstrate that any radioactivity that remains after D&D will not cause exposure to radioactive contaminants to exceed acceptable limits. This requires knowledge of the distribution of radionuclides in the remaining material and their potential release mechanisms from the material to the contacting groundwater. In this study the concern involves radionuclide contamination in activated concrete in the ICI Sump below the containment building. Figures 1-3 are schematic representations of the ICI Sump. Figure 2 and 3 contain the relevant dimensions needed for the analysis. The key features of Figures 2 and 3 are the 3/8-inch carbon steel liner that isolates the activated concrete from the pit and the concrete wall, which is between 7 feet and 7 feet 2 inches thick. During operations, a small neutron flux from the reactor activated the carbon steel liner and the concrete outside the liner. Current MY plans call for filling the ICI sump with compacted sand.

SULLIVAN,T.M.

2003-08-23T23:59:59.000Z

204

Concrete Structure Design Using Mixed-Integer Nonlinear ...  

E-Print Network (OSTI)

Nov 24, 2009 ... The demand on the RC elements in terms of displacements and forces ... necessary to model the resistive forces provided by the concrete, elastic-perfectly plastic material response ...... Material and installation unit price of reinforcement ..... Department of Energy, under Contract DE-AC02-06CH11357 and...

205

Modeling of Sulfate Resistance of Flyash Blended Cement Concrete Materials  

E-Print Network (OSTI)

Modeling of Sulfate Resistance of Flyash Blended Cement Concrete Materials Barzin Mobasher1 or water with high SO3 content. External sulfate 2007 World of Coal Ash (WOCA), May 7-10, 2007, Covington, the effect of curing (especially in the case of blended cements) and the effect of the pH change during

Mobasher, Barzin

206

Innovative technologies for recycling contaminated concrete and scrap metal  

SciTech Connect

Decontamination and decommissioning of US DOE`s surplus facilities will generate enormous quantities of concrete and scrap metal. A solicitation was issued, seeking innovative technologies for recycling and reusing these materials. Eight proposals were selected for award. If successfully developed, these technologies will enable DOE to clean its facilities by 2019.

Bossart, S.J. [USDOE Morgantown Energy Technology Center, WV (United States); Moore, J. [USDOE Oak Ridge Operations Office, TN (United States)

1993-09-01T23:59:59.000Z

207

Corresponding author Measuring Concrete Crosstie Rail Seat Pressure Distribution  

E-Print Network (OSTI)

Mediavilla 4 Rail Transportation and Engineering Center ­ RailTEC 2 Department of Civil and Environmental loads and cumulative freight tonnages, as well as increased interest in high speed passenger rail1 Corresponding author Measuring Concrete Crosstie Rail Seat Pressure Distribution with Matrix

Barkan, Christopher P.L.

208

Radiolytic gas production from concrete containing Savannah River Plant waste  

DOE Green Energy (OSTI)

To determine the extent of gas production from radiolysis of concrete containing radioactive Savannah River Plant waste, samples of concrete and simulated waste were irradiated by /sup 60/Co gamma rays and /sup 244/Cm alpha particles. Gamma radiolysis simulated radiolysis by beta particles from fission products in the waste. Alpha radiolysis indicated the effect of alpha particles from transuranic isotopes in the waste. With gamma radiolysis, hydrogen was the only significant product; hydrogen reached a steady-state pressure that increased with increasing radiation intensity. Hydrogen was produced faster, and a higher steady-state pressure resulted when an organic set retarder was present. Oxygen that was sealed with the wastes was depleted. Gamma radiolysis also produced nitrous oxide gas when nitrate or nitrite was present in the concrete. With alpha radiolysis, hydrogen and oxygen were produced. Hydrogen did not reach a steady-state pressure at <140 psi. From these results, estimates of pressure in conceptual containers (cylinders 2 feet ID by 10 feet tall, 90% full) of SRP waste concrete were made. During the first 300 years of storage when radiolysis will mainly be from beta-gamma radiation (from /sup 137/Cs and /sup 90/Sr), hydrogen will reach a steady-state pressure of 8 to 28 psi, and oxygen will be partially consumed. These predictions were confirmed by measurement of gas produced over a short time in a container of concrete and actual SRP waste. The tests with simulated waste also indicated that nitrous oxide may form, but because of the low nitrate or nitrite content of the waste, the maximum pressure of nitrous oxide after 300 years will be <60 psi. After decay of these fission products, alpha radiolysis from /sup 238/Pu and /sup 239/Pu will predominate; the hydrogen and oxygen pressures will increase to >200 psi.

Bibler, N.E.

1978-01-01T23:59:59.000Z

209

Construction of Recurrent Fractal Interpolation Surfaces with Function Scaling Factors and Estimation of Box-counting Dimension on Rectangular Grids  

E-Print Network (OSTI)

We consider a construction of recurrent fractal interpolation surfaces with function vertical scaling factors and estimation of their box-counting dimension. A recurrent fractal interpolation surface (RFIS) is an attractor of a recurrent iterated function system (RIFS) which is a graph of bivariate interpolation function. For any given data set on rectangular grids, we construct general recurrent iterated function systems with function vertical scaling factors and prove the existence of bivariate functions whose graph are attractors of the above constructed RIFSs. Finally, we estimate lower and upper bounds for the box-counting dimension of the constructed RFISs.

Chol-Hui Yun; Hui-Chol Choi; Hyong-Chol O

2013-07-10T23:59:59.000Z

210

Of FFT-based convolutions and correlations, with application to solving Poisson's equation in an open rectangular pipe  

Science Conference Proceedings (OSTI)

A new method is presented for solving Poisson's equation inside an open-ended rectangular pipe. The method uses Fast Fourier Transforms (FFTs)to perform mixed convolutions and correlations of the charge density with the Green function. Descriptions are provided for algorithms based on theordinary Green function and for an integrated Green function (IGF). Due to its similarity to the widely used Hockney algorithm for solving Poisson'sequation in free space, this capability can be easily implemented in many existing particle-in-cell beam dynamics codes.

Ryne, Robert D.

2011-11-07T23:59:59.000Z

211

Activities in support of continuing the service of nuclear power plant concrete structures  

SciTech Connect

In general, nuclear power plant concrete structure s performance has been very good; however, aging of concrete structures occurs with the passage of time that can potentially result in degradation if is effects are not controlled. Safety-related nuclear power plant concrete structures are described. In-service inspection and testing requirements in the U.S. are summarized. The interaction of the license renewal process and concrete structures is noted. A summary of operating experience related to aging of nuclear power plant concrete structures is provided. Several candidate areas are identified where additional research would be beneficial for aging management of nuclear power plant concrete structures. Finally, an update on recent activities at Oak Ridge National Laboratory related to aging management of nuclear power plant concrete structures is provided.

Naus, Dan J [ORNL

2012-01-01T23:59:59.000Z

212

Ray Tracing through the Edge Focusing of Rectangular Benders and an Improved Model for the Los Alamos Proton Storage Ring  

SciTech Connect

Particle ray tracing through simulated 3D magnetic fields was executed to investigate the effective quadrupole strength of the edge focusing of the rectangular bending magnets in the Los Alamos Proton Storage Ring (PSR). The particle rays receive a kick in the edge field of the rectangular dipole. A focal length may be calculated from the particle tracking and related to the fringe field integral (FINT) model parameter. This tech note introduces the baseline lattice model of the PSR and motivates the need for an improvement in the baseline model's vertical tune prediction, which differs from measurement by .05. An improved model of the PSR is created by modifying the fringe field integral parameter to those suggested by the ray tracing investigation. This improved model is then verified against measurement at the nominal PSR operating set point and at set points far away from the nominal operating conditions. Lastly, Linear Optics from Closed Orbits (LOCO) is employed in an orbit response matrix method for model improvement to verify the quadrupole strengths of the improved model.

Kolski, Jeffrey S. [Los Alamos National Laboratory; Barlow, David B. [Los Alamos National Laboratory; Macek, Robert J. [Los Alamos National Laboratory; McCrady, Rodney C. [Los Alamos National Laboratory

2011-01-01T23:59:59.000Z

213

The Effect of Hydrostatic Pressure on the Fracture of Concrete  

Science Conference Proceedings (OSTI)

The topic of this research deals with (1) the hydrostatic distribution along dam upstream face cracks and (2) the material resistance versus cracking when water pressure is present in the crack. Fracture experiments were performed where hydrostatic pressure was present during formation and growth of a crack in a concrete specimen. Experimental results yielded information regarding both the pressure distribution along cracks and the fracture properties as affected by the presence of hydrostatic pressure. ...

1995-12-14T23:59:59.000Z

214

Concrete Cleaning, Inc. centrifugal shot blaster: Baseline report  

Science Conference Proceedings (OSTI)

The centrifugal shot blaster technology was tested and is being evaluated at Florida International University (FIU) as a baseline technology. In conjunction with FIU`s evaluation of efficiency and cost, this report covers the evaluation conducted for safety and health issues. It is a commercially available technology and has been used for various projects at locations throughout the country. The centrifugal shot blaster is an electronically operated shot blast machine that has been modified to remove layers of concrete to varying depths. A hardened steel shot propelled at a high rate of speed abrades the surface of the concrete. The depth of material removed is determined by the rate of speed the machine is traveling and the volume of shot being fired into the blast chamber. The steel shot is recycled and used over until it is pulverized into dust, which ends up in the waste container with the concrete being removed. Debris is continually vacuumed by a large dust collection system attached to the shot blaster. The safety and health evaluation during the human factors assessment focused on two main areas: noise and dust.

NONE

1997-07-31T23:59:59.000Z

215

Blunt-crack band propagation in finite-element analysis for concrete structures. [LMFBR  

SciTech Connect

The knowledge of concrete fracture is needed in nuclear reactor safety. The question of safety arises from the potential of concrete to crack under thermal loading. It has been postulated that structural concrete could be exposed to very high temperature, which may result from hot reactor coolant or even core debris coming in direct contact with the concrete. The utilization of the blunt crack approach for simulating concrete cracking in a general-purpose code is explored. The difficulties encountered in establishing the proper direction of crack propagation in an arbitrary discretization are described. Crack propagation is considered within the context of two types of solution techniques: (1) implicit solution of the static crack advance, and (2) explicit time integration using a dynamic relaxation technique to simulate the static crack advance. Also, in both solution techniques an elastic model is used to characterize the concrete.

Pfeiffer, P.A.; Bazant, Z.P.; Marchertas, A.H.

1983-01-01T23:59:59.000Z

216

Effects of composition and exposure on the solar reflectance of Portland Cement Concrete  

SciTech Connect

Increasing the solar reflectance (albedo) of a paved surface keeps it cooler in the sun, reducing convection of heat from pavement to air and thereby decreasing the ambient air temperature. Lower air temperatures decrease demand for cooling energy and slow the formation of urban smog. Variations with composition and environmental exposure of the albedos of portland cement concrete pavements were investigated through laboratory fabrication and exposure of 32 mixes of concrete. Concrete albedo generally correlated with cement albedo and sand albedo and, after abrasion, with rock albedo. Cement albedo had a disproportionately strong influence on the reflectance of concrete. Simulated weathering, soiling, and abrasion each reduced average concrete albedo, though some samples became slightly more reflective through weathering or soiling. Concrete albedo grew as the cement hydration reaction progressed, but stabilized within six weeks of casting.

Levinson, Ronnen; Akbari, Hashem

2002-06-01T23:59:59.000Z

217

Corium Spreading Over Concrete: The Vulcano VE-U7 and VE-U8 Tests  

Science Conference Proceedings (OSTI)

Two experiments have been performed in the VULCANO facility in which prototypic corium has been spread over concrete. In the VE-U7 test, a mixture representative of what can be expected at the opening of EPR reactor-pit gate has been spread on siliceous concrete and on a reference channel in inert refractory ceramic. The spreading progression was not much affected by the presence of concrete and sparging gases. In the VE-U8 test, a UO{sub 2}-ZrO{sub 2} mixture, prototypic of in-vessel corium, has been spread over a lime-siliceous concrete. Although residual power was not simulated in this experiment, up to 2 cm of concrete have been eroded during the test. Results in terms of spreading behaviour, effects of gases, concrete erosion and thermal attack are presented and discussed. (authors)

Journeau, Christophe; Boccaccio, Eric; Fouquart, Pascal; Jegou, Claude; Piluso, Pascal [CEA Cadarache, F-13108 St Paul lez Durance cedex (France)

2002-07-01T23:59:59.000Z

218

Effects of Radiation on Concrete: A Literature Survey and Path Forward  

Science Conference Proceedings (OSTI)

An important focus for the long-term operation of nuclear plants is the aging of plant concrete structures. The containment building, biological shielding, and support concrete are examples of concrete structures that are of primary importance in the operation of a nuclear plant. These and other safety-related structures at a plant site must be capable of maintaining structural capability for the operating life of the plant. The continued operation of existing units is potentially challenged by a change ...

2012-05-07T23:59:59.000Z

219

Mercury Leachability From Concretes That Contain Fly Ashes and Activated Carbon Sorbents  

Science Conference Proceedings (OSTI)

This report presents new laboratory data on the leaching of mercury from concrete that contains fly ash and powdered activated carbon (PAC) sorbents used to capture mercury. The concretes studied during this project were made with fly ashes from lignite and subbituminous coal, including fly ashes containing PAC. Only very low levels of mercuryless than 5 parts per trillionwere leached from the fly ash concretes in both 18-hour and 7-day laboratory leach tests.

2007-07-18T23:59:59.000Z

220

Characterizing the Nano and Micro Structure of Concrete to Improve its Durability  

E-Print Network (OSTI)

Characterizing the Nano and Micro Structure of Concrete todeveloped to characterize the nano and microstructure ofis providing new insight on the nano scale of the cement

Monteiro, P.J.M.

2009-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "rectangular precast concrete" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Characterizing the nano and micro structure of concrete to improve its durability  

E-Print Network (OSTI)

Characterizing the Nano and Micro Structure of Concrete todeveloped to characterize the nano and microstructure ofis providing new insight on the nano scale of the cement

Monteiro, P.J.M.

2008-01-01T23:59:59.000Z

222

Life-Cycle Evaluation of Concrete Building Construction as a Strategy for Sustainable Cities  

E-Print Network (OSTI)

5. Map of California climate zones with average HDD and CDDaverage across climate zones) . 36 Figure 4-7.between steel and concrete frames by climate zone and

Stadel, Alexander

2013-01-01T23:59:59.000Z

223

Temperature and pore pressure distribution in a concrete slab during the microwave decontamination process  

SciTech Connect

As an application of microwave engineering, the new technology of concrete decontamination and decommissioning using microwave energy has been recently developed. The temperature and pore pressure within the concrete are studied theoretically in this paper. The heat and mass transfer within the porous concrete, coupled with temperature dependent dielectric property are investigated. The effects of microwave frequency (f), microwave power intensity (Q{sub 0,ave}), concrete porosity ({phi}) on the temperature and pore pressure distributions and their variations are fully discussed. The effects of the variation of complex dielectric permittivity ({epsilon}) and presentation of different steel reinforcements are also illustrated.

Li, W.; Ebadian, M.A. [Florida International Univ., Miami, FL (United States). Dept. of Mechanical Engineering; White, T.L.; Grubb, R.G.; Foster, D. Jr. [Oak Ridge National Lab., TN (United States)

1994-10-01T23:59:59.000Z

224

Properties of concrete incorporating high volumes of ASTM Class F fly ash  

E-Print Network (OSTI)

This thesis presents the results of research performed in developing high-volume fly ash (HVFA) concrete incorporating ASTM Type I cement and ASTM Class F fly ash from Big Brown Power Plant of TU Electric, Texas. In HVFA concrete, the proportion of fly ash was 58 percent by weight of the total cementitious materials, the water and cement content were kept low at 115 and 155 k g/M3 , respectively. A broad range of engineering properties was investigated including compressive strength, flexural strength, splitting-tensile strength, Young's modulus of elasticity, drying shrinkage, resistance to freeze-thaw cycling, pore structure and activation energy. A preliminary economic analysis was also performed on HVFA concrete. The HVFA concrete evaluated in this study had satisfactory workability and setting characteristics. It also exhibited excellent mechanical properties with satisfactory early age strength and good long-term strength development. The HVFA concrete had relatively low drying shrinkage and a very fine pore system. Excellent durability under freeze-thaw cycling was also found for the air-entrained HVFA concrete. Results from activation energy test show that strength gain of the HVFA concrete under isothermal curing conditions could be modeled appropriately using Plowman's logarithmic strength-age model. The relative strength-maturity relationship was established for the HVFA concrete containing various percentages of additional gypsum. The HVFA concrete investigated was determined to be cost effective. It was shown that about two and half dollars per cubic meter could be saved through savings on portland cement.

Li, Wei Tung

1995-01-01T23:59:59.000Z

225

Analyses of U.S. and R.F. Depleted-Uranium Concrete/Steel Transport...  

NLE Websites -- All DOE Office Websites (Extended Search)

the DUO 2 -aggregates' physical properties and chemical durability, estimated capital and production costs of SNF casks using DU concrete (DUCRETE TM ), and studied the shielding...

226

Summary of Uranium Solubility Studies in Concrete Waste Forms and Vadose Zone Environments  

SciTech Connect

One of the methods being considered for safely disposing of Category 3 low-level radioactive wastes is to encase the waste in concrete. Concrete encasement would contain and isolate the waste packages from the hydrologic environment and act as an intrusion barrier. The current plan for waste isolation consists of stacking low-level waste packages on a trench floor, surrounding the stacks with reinforced steel, and encasing these packages in concrete. These concrete-encased waste stacks are expected to vary in size with maximum dimensions of 6.4 m long, 2.7 m wide, and 4 m high. The waste stacks are expected to have a surrounding minimum thickness of 15 cm of concrete encasement. These concrete-encased waste packages are expected to withstand environmental exposure (solar radiation, temperature variations, and precipitation) until an interim soil cover or permanent closure cover is installed and to remain largely intact thereafter. Any failure of concrete encasement may result in water intrusion and consequent mobilization of radionuclides from the waste packages. This report presents the results of investigations elucidating the uranium mineral phases controlling the long-term fate of uranium within concrete waste forms and the solubility of these phases in concrete pore waters and alkaline, circum-neutral vadose zone environments.

Golovich, Elizabeth C.; Wellman, Dawn M.; Serne, R. Jeffrey; Bovaird, Chase C.

2011-09-30T23:59:59.000Z

227

Energy Efficiency Improvement and Cost Saving Oportunities for the Concrete Industry  

E-Print Network (OSTI)

of energy management: energy audits/assessments, energyto Titan America, energy audits conducted in concrete plantsmanagement programs Energy audit Energy teams Employee

Kermeli, Katerina

2013-01-01T23:59:59.000Z

228

Unsteady flow and heat transfer in a channel with a built-in tandem of rectangular cylinders  

Science Conference Proceedings (OSTI)

The incompressible unsteady flow past a channel with a pair of cylinders of rectangular cross section, placed in tandem normal to the flow, is investigated by numerical simulation. The objective is to evaluate the effect of cylinder separation distance, S/H, on the flow behavior and heat transfer on the channel walls, over a range of Reynolds numbers. Above a critical Reynolds number, these flows bifurcate to a time-periodic self-sustained oscillatory state. The results reveal for S/H = 2.0 three distinct flow patterns: steady flow (Re = 200), time-periodic oscillatory state (400 {le} Re {le} 800), and quasi-periodic oscillatory flow (Re = 1,000). For S/H 600.

Valencia, A. [Universidad de Chile, Santiago (Chile). Dept. de Ingenieria Mecanica

1996-05-10T23:59:59.000Z

229

Extremal transmission through a microwave photonic crystal and the observation of edge states in a rectangular Dirac billiard  

E-Print Network (OSTI)

This article presents experimental results on properties of waves propagating in an unbounded and a bounded photonic crystal consisting of metallic cylinders which are arranged in a triangular lattice. First, we present transmission measurements of plane waves traversing a photonic crystal. The experiments are performed in the vicinity of a Dirac point, i.e., an isolated conical singularity of the photonic band structure. There, the transmission shows a pseudodiffusive 1/L dependence, with $L$ being the thickness of the crystal, a phenomenon also observed in graphene. Second, eigenmode intensity distributions measured in a microwave analog of a relativistic Dirac billiard, a rectangular microwave billiard that contains a photonic crystal, are discussed. Close to the Dirac point states have been detected which are localized at the straight edge of the photonic crystal corresponding to a zigzag edge in graphene.

S. Bittner; B. Dietz; M. Miski-Oglu; A. Richter

2011-10-14T23:59:59.000Z

230

Use of Residual Solids from Pulp and Paper Mills for Enhancing Strength and Durability of Ready-Mixed Concrete  

SciTech Connect

This research was conducted to establish mixture proportioning and production technologies for ready-mixed concrete containing pulp and paper mill residual solids and to study technical, economical, and performance benefits of using the residual solids in the concrete. Fibrous residuals generated from pulp and paper mills were used, and concrete mixture proportions and productions technologies were first optimized under controlled laboratory conditions. Based on the mixture proportions established in the laboratory, prototype field concrete mixtures were manufactured at a ready-mixed concrete plant. Afterward, a field construction demonstration was held to demonstrate the production and placement of structural-grade cold-weather-resistant concrete containing residual solids.

Tarun R. Naik; Yoon-moon Chun; Rudolph N. Kraus

2003-09-18T23:59:59.000Z

231

Materials development and field demonstration of high-recycled-content concrete for energy-efficient building construction  

SciTech Connect

The project developed high-recycled-content concrete material with balanced structural and thermal attributes for use in energy-efficient building construction. Recycled plastics, tire, wool, steel and concrete were used as replacement for coarse aggregates in concrete and masonry production. With recycled materials the specific heat and thermal conductivity of concrete could be tailored to enhance the energy-efficiency of concrete buildings. A comprehensive field project was implemented which confirmed the benefits of high-recycled-content concrete for energy-efficient building construction.

Ostowari, Ken; Nosson, Ali

2000-09-30T23:59:59.000Z

232

Superposition of the NeymanScott Rectangular Pulses Model and the Poisson White Noise Model for the Representation of Tropical Rain Rates  

Science Conference Proceedings (OSTI)

A point process model for tropical rain rates is developed through the derivation of the third moment expression for a combined point process model. The model is a superposition of a NeymanScott rectangular pulse model and a Poisson white noise ...

Mark L. Morrissey

2009-04-01T23:59:59.000Z

233

Probability based load factors for design of concrete containment structures  

SciTech Connect

This paper describes a procedure for developing probability-based load combinations for the design of concrete containments. The proposed criteria are in a load and resistance factor design (LRFD) format. The load factors and resistance factors are derived for use in limit states design and are based on a target limit state probability. In this paper, the load factors for accident pressure and safe shutdown earthquake are derived for three target limit state probabilities. Other load factors are recommended on the basis of prior experience with probability-based design criteria for ordinary building construction. 6 refs.

Hwang, H.; Kagami, S.; Reich, M.; Ellingwood, B.; Shinozuka, M.

1985-01-01T23:59:59.000Z

234

Flexural Fatigue Performance of CFRP Prestressed Concrete Poles  

E-Print Network (OSTI)

Applications, ACI Special Publication SP245-1, Eds R. El-Hacha and S.H. Rizkalla. [17] BS EN 1992-1-1:2004 (2004). Eurocode 2: Design of Concrete Structures. General Rules and Rules for Buildings, BSI. [18] Terrasi G.P. and Lees, J.M. (2006). CFRP... . However, as the deflection under a 6 point load is greater than the deflection under an equivalent UDL, this is a conservative approach. The span and loading arrangements were selected based on a sectional analysis of the critical cross...

Roberts, E. E.; Lees, J. M.; Hoult, N. A.

2012-04-24T23:59:59.000Z

235

CONCRETE REFLECTED ARRAYS OF U(93.2) METAL  

SciTech Connect

During the period from 1963 1973, experiments involving highly enriched uranium units were performed at the Oak Ridge National Laboratory Critical Experiments Facility to determine various critical configurations of three-dimensional arrays. The experiments formed a four-part series, and were reported by several different experimenters; the results of interest for this evaluation are those reported for the fourth experimentation, Critical Three-Dimensional Arrays of Neutron Interacting Units: Part IV, published and performed by D.W.Magnuson (Ref 1). Information is also available in the logbook . This set of experiments utilized subcritical metal units on a split table apparatus to determine critical configurations for 222 arrangements of highly enriched uranium reflected by concrete. Magnuson manipulated the configuration of several uranium cylinders and blocks within a concrete reflector. The different permutations utilized uranium cylinders of two different heights in various positions in the three dimensional array; certain cases also placed thin uranium blocks on top of the cylinders. The thickness of the surrounding concrete, as well as the inner dimensions of the concrete reflector was also varied in certain cases. The variations resulted in fourteen different experimental permutations or configurations. All fourteen configurations were judged to be unacceptable for use as criticality safety benchmarks. All experiments were initially evaluated; however only three configurations were evaluated in detail. Configurations 2, 4, 6 and 12 were not evaluated in detail because they are subcritical and configurations 5, 7, 8, 9, and 10 were also were not evaluated in detail because they were supercritical by more than beta effective (~0.007), or prompt critical. The experiments evaluated in detail for this benchmark were configurations 1, 3, and 11. The experimental report also contains the information for HEU-MET-FAST-056. Closely related work has been recorded in HEU-MET-FAST-053, which is a benchmark evaluation of a different series of three dimensional array experiments with four different moderator materials. HEU-MET-FAST-023 and HEU-MET-FAST-026 are also related because they utilize the same metal cylinders as these experiments.

Mackenzie Gorham; John D. Bess; J. Blair Briggs; Virginia Dean; Davis Reed

2010-09-01T23:59:59.000Z

236

Ground resistance of concrete foundations in substation yards  

SciTech Connect

The reinforced concrete foundations in a substation yard have extensive reinforcing steel which is in metallic connection with the laid ground conductor. The foundations may contribute significantly to the dissipation of the fault and leakage currents. Simple to use equations and graphs are presented in this paper to determine the ground resistance of various types of foundations encountered in substation yards. The validity of the analytical approach has been verified with scale model tests. The ground resistance of the foundations estimated as suggested in the paper can be used to evaluate the role of the foundations as grounding element.

Thapar, B.; Ferrer, O. (Montana State Univ., Bozeman, MT (USA)); Blank, D.A. (Bonneville Power Administration, Portland, OR (USA))

1990-01-01T23:59:59.000Z

237

Phosphogypsum slag aggregate-based asphaltic concrete mixes  

Science Conference Proceedings (OSTI)

Phosphogypsum is a by-product from the production of phosphoric acid used in the fertilizer and chemical industries. Large production rates and problems associated with its stockpiling have led researchers to seek alternative uses for phosphogypsum, primarily as a construction material. One such use is the extraction of sulfur dioxide for the production of sulfuric acid, a process that also generates a by-product slag aggregate. This study investigated the feasibility of using this slag aggregate in asphaltic concrete binder course mixes. The physical properties of the slag aggregate, such as gradation, specific gravity, absorption, unit weight, and void content, were determined, as well as its durability and environmental characteristics. The Marshall mix design method was used to obtain the optimum asphalt content for this aggregate, while moisture susceptibility was examined using the boiling and modified Lottman tests. Indirect tensile, resilient modulus, and dynamic creep tests were performed on the mix to evaluate its performance potential. The results of the study indicate that phosphogypsum-based slag aggregate can be successfully employed in asphaltic concrete binder course mixtures.

Foxworthy, P.T. [Terracon Consultants, Inc., Lenexa, KS (United States); Nadimpalli, R.S.; Seals, R.K. [Louisiana State Univ., Baton Rouge, LA (United States)

1996-07-01T23:59:59.000Z

238

Semisubmersible LNG plant design uses concrete storage buoy  

SciTech Connect

The ARGE '76 consortium, which includes Bilfinger and Berger, Blohm and Voss A.G., Dyckerhoff and Widmann A.G., Kabelmetal, Linde A.G., and Preussag A.G., has designed a system for exploiting marginal-sized offshore gasfields comprising an LNG liquefaction plant on a steel semisubmersible, a complete transfer system, and a concrete LNG storage buoy with a capacity of 125,000 cu m. The plant can handle 15.36 million cu m/day of natural gas production using a modified mixed refrigerant cycle with precooling from four nearly identical lines of the same capacity. The semisubmersible deck is 124 m square and 12 m deep. Quarters would be built for 160 men. The plant can continue to operate up to an inclination of 5/sup 0/. The storage buoy features a 64 m dia spherical concrete storage tank surrounded by 20 cylindrical ballast tanks. A 10 m dia center column rising from the tank supports a steel deck 20 m above sea level and also houses the transfer and ballast pipes and pumps. A flexible length of Flexwell-LNG transfer pipes 700 m long connects the semisubmersible and the storage tank, which will be 600 m apart.

1978-02-01T23:59:59.000Z

239

Fire analysis of steel-concrete composite beam with interlayer slip  

Science Conference Proceedings (OSTI)

The paper discusses the effects of slip and moisture transfer on the behaviour of a planar steel-concrete composite beam subject to fire conditions. The moisture and heat transfer is assumed to be governed by a coupled problem, while the mechanical behaviour ... Keywords: Fire, High temperatures, Moisture and heat transfer, Slip between layers, Steel-concrete composite beam

Toma Hozjan; Miran Saje; Stanislav Srp?i?; Igor Planinc

2011-01-01T23:59:59.000Z

240

Signicance of localized pore pressures to the genesis of septarian concretions  

E-Print Network (OSTI)

causing a reduction of the effective stress. Analysis of the stress conditions and crack morphology the magnitude of the excess pore pressure and the stress corrosion limit of the concretion body. A review distribution of strength and effective stress in the concretion. Crack orientations mostly re¯ect stress

Note: This page contains sample records for the topic "rectangular precast concrete" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Release of Mercury During Curing of Concrete Containing Fly Ash and Mercury Sorbent Material  

Science Conference Proceedings (OSTI)

This report provides laboratory data on mercury release during the initial curing stage of concrete made with fly ash or mixtures of fly ash and activated carbon containing mercury. These experiments suggest that mercury is not released from these concretes during initial curing.

2002-12-09T23:59:59.000Z

242

Carbon Dioxide Sequestration in Concrete Using Vacuum-Carbonation Alain Azar, Prof. Yixin Shao  

E-Print Network (OSTI)

Carbon Dioxide Sequestration in Concrete Using Vacuum-Carbonation Alain Azar, Prof. Yixin Shao increase in Carbon dioxide (CO2) emissions over the past five decades, specific ways to reduce. Early age carbonation curing of concrete is an effective measure to sequester recovered CO2 in lime

Barthelat, Francois

243

Joint interaction with embedded concretions: joint loading congurations inferred from propagation paths  

E-Print Network (OSTI)

Joint interaction with embedded concretions: joint loading con®gurations inferred from propagation The interaction between propagating joints and embedded concretions in a Devonian black shale near Seneca Lake, NY, permits identi®cation of the loading con®gurations responsible for two joint sets of dierent ages striking

Engelder, Terry

244

New Air-Entraining Admixtures for Concrete Using High-Carbon Fly Ash  

Science Conference Proceedings (OSTI)

A promising new air-entraining admixture has been developed by the leading North American admixture producer. Independent, EPRI-sponsored testing indicated the admixture was suitable for use with concretes that contain fly ashes with levels of unburned carbon higher than the typical 3-4 percent allowed in the concrete industry.

2002-03-20T23:59:59.000Z

245

Primer on Durability of Nuclear Power Plant Reinforced Concrete Structures - A Review of Pertinent Factors  

Science Conference Proceedings (OSTI)

The objective of this study was to provide a primer on the environmental effects that can affect the durability of nuclear power plant concrete structures. As concrete ages, changes in its properties will occur as a result of continuing microstructural changes (i.e., slow hydration, crystallization of amorphous constituents, and reactions between cement paste and aggregates), as well as environmental influences. These changes do not have to be detrimental to the point that concrete will not be able to meet its performance requirements. Concrete, however, can suffer undesirable changes with time because of improper specifications, a violation of specifications, or adverse performance of its cement paste matrix or aggregate constituents under either physical or chemical attack. Contained in this report is a discussion on concrete durability and the relationship between durability and performance, a review of the historical perspective related to concrete and longevity, a description of the basic materials that comprise reinforced concrete, and information on the environmental factors that can affect the performance of nuclear power plant concrete structures. Commentary is provided on the importance of an aging management program.

Naus, Dan J [ORNL

2007-02-01T23:59:59.000Z

246

Investigation on the Parameters Affecting the De-Icing Salt Scaling Resistance of Fly Ash Concrete  

Science Conference Proceedings (OSTI)

In scaling of concrete by de-icing salts, the mortar near the surface flakes or peels away. This report presents the results of an R&D laboratory study to examine the scaling of high ash content concrete from the use of salts used routinely in cold climates to melt ice and snow on roads and sidewalks.

1998-06-29T23:59:59.000Z

247

Touch and Step Voltage Measurements on Field Installed Ground Grid and Concrete Pads  

Science Conference Proceedings (OSTI)

Concrete is commonly used as building material in substations (within the substation fence) and around substations (outside the fence) for driveways, foundations, walkways, oil containment, sidewalks, walls, and other structures. This project evaluates the effects of various types (reinforced, non-reinforced) and conditions (dry, wet) of concrete structures on step, touch, and transfer touch voltages in and around substations.

2009-12-03T23:59:59.000Z

248

Microplane constitutive model M4L for concrete. II: Calibration and validation  

Science Conference Proceedings (OSTI)

This paper, Part II of a two-part study, presents the numerical calibration and validation of the microplane constitutive model M4L for concrete formulated in the preceding part. The model parameters are firstly calibrated through optimum fitting of ... Keywords: Concrete, Finite elements, Fracture and damage, Microplane model, Structural analysis

Jiabin Li, Nguyen V. Tue, Ferhun C. Caner

2013-11-01T23:59:59.000Z

249

Heat Transfer Analysis of Asphalt Concrete Pavement Based on Snow Melting  

Science Conference Proceedings (OSTI)

On the basis of Wuhan district weather conditions of January 5, 2010, heat transfer mechanism of Beijing-Zhuhai Expressway Hubei section of asphalt concrete pavement based on snow melting is analyzed and the model of heat transmission is established. ... Keywords: asphalt concrete pavement, ground-source heat, pump, deicing and snow melting, heat flux

Yan-ping Tu; Jie Li; Chang-sheng Guan

2010-06-01T23:59:59.000Z

250

Efficient CFRP Strap Configurations for the Shear Strengthening of Reinforced Concrete T-Beams  

E-Print Network (OSTI)

2 Specimen capacities Specimen fcu, (MPa) Ultimate Shear Force (kN) Percentage Increase versus B1/25 Maximum Mid- span Deflection (mm) Failure Mode B1/25 24.8 88.2 - 15.5 Shear in Concrete B2/45/H/20 19.8 95.4 8.2 15.6 Shear in Concrete...

Hoult, N. A.; Lees, J. M.

2012-02-27T23:59:59.000Z

251

Coupled simulation of wave propagation and water pumping phenomenon in driven concrete piles  

Science Conference Proceedings (OSTI)

The purpose of the paper is to simulate the water pumping phenomenon that may cause damage to driven concrete pile below water. The cracked concrete is modeled as water saturated porous media, where the cracked region is given a high permeability. A ... Keywords: Coupled, Cracking, Hydro-mechanical, Pile, Porous media, Wave propagation

P. Kettil; G. Engstrm; N. -E. Wiberg

2007-02-01T23:59:59.000Z

252

Investigation of Potential Concrete Tie Rail Seat Deterioration Mechanisms: Cavitation Erosion and Hydraulic Pressure Cracking  

E-Print Network (OSTI)

Investigation of Potential Concrete Tie Rail Seat Deterioration Mechanisms: Cavitation Erosion and Hydraulic Pressure Cracking 10-2411 Transportation Research Board 89th Annual Meeting Submitted: November 15-2411 1 ABSTRACT Rail seat deterioration (RSD) is the most critical problem with concrete tie performance

Barkan, Christopher P.L.

253

Investigating the Role of Moisture in Concrete Tie Rail Seat Deterioration  

E-Print Network (OSTI)

Investigating the Role of Moisture in Concrete Tie Rail Seat Deterioration Proceedings of the 2009 ABSTRACT Rail seat deterioration (RSD) is the most critical problem with concrete tie performance on North American freight railroads. Currently, the causes and mechanics of RSD are not sufficiently understood

Barkan, Christopher P.L.

254

Thermal Hydraulic and Fission Product Release Behavior During Core/Concrete Interactions  

Science Conference Proceedings (OSTI)

Experiments have been performed to characterize the downward heat transfer from molten corium to ablating concrete by using simulant fluids in a laboratory-scale apparatus. Existing and new models for such phenomena have been compared with these and available large-scale molten corium concrete interaction experiments.

1993-09-03T23:59:59.000Z

255

Use of GFRP Grid for Innovative Concrete Sandwich Panels Jonathan G. Soriano1  

E-Print Network (OSTI)

as a shear transfer mechanism for concrete sandwich wall panels typically used for a building envelope at the North Carolina State University focused on the behavior of insulated concrete sandwich wall panels to affect the shear transfer, such as the type of rigid foam insulation, insulation thickness

256

Composite element algorithm for the thermal analysis of mass concrete: Simulation of lift joint  

Science Conference Proceedings (OSTI)

Based on the principle of composite element method (CEM), the thermal algorithm for the massive concrete containing lift joint is developed, in which the lift joint segments are embedded within the composite elements. The composite element contains sub-elements ... Keywords: Composite element method, Lift joint, Mass concrete, Temperature field

S. H. Chen; P. F. Su; I. Shahrour

2011-05-01T23:59:59.000Z

257

A PERMEABLE ACTIVE AMENDMENT CONCRETE (PAAC) FOR CONTAMINANT REMEDIATION AND EROSION CONTROL  

Science Conference Proceedings (OSTI)

The final project report for SEED SERDP ER - 2134 describes the development of permeable active amendment concrete (PAAC), which was evaluated through four tasks: 1) development of PAAC; 2) assessment of PAAC for contaminant removal; 3) evaluation of promising PAAC formulations for potential environmental impacts; and 4) assessment of the hydraulic, physical, and structural properties of PAAC. Conventional permeable concrete (often referred to as pervious concrete) is concrete with high porosity as a result of an extensive and interconnected void content. It is made from carefully controlled amounts of water and cementitious materials used to create a paste that forms a coating around aggregate particles. The mixture has a substantial void content (e.g., 15% - 25%) that results in a highly permeable structure that drains quickly. In PAAC, the aggregate material is partly replaced by chemically-active amendments that precipitate or adsorb contaminants in water that flows through the concrete interstices. PAAC combines the relatively high structural strength, ample void space, and water permeability of pervious concrete with the contaminant sequestration ability of chemically-active amendments to produce a new material with superior durability and ability to control contaminant mobility. The high surface area provided by the concrete interstices in PAAC provides significant opportunity for contaminants to react with the amendments incorporated into the concrete matrix. PAAC has the potential to immobilize a large variety of organic and inorganic contaminants by incorporating different active sequestering agents including phosphate materials (rock phosphate), organoclays, zeolite, and lime individually or in combinations.

Knox, A.; Paller, M.; Dixon, K.

2012-06-29T23:59:59.000Z

258

Prediction and multi-objective optimization of high-strength concrete parameters via soft computing approaches  

Science Conference Proceedings (OSTI)

The optimization of composite materials such as concrete deals with the problem of selecting the values of several variables which determine composition, compressive stress, workability and cost etc. This study presents multi-objective optimization (MOO) ... Keywords: High-strength concrete, Meta-heuristics, Multiple objective optimization, Prediction

Adil Baykaso?lu; Ahmet zta?; Erdo?an zbay

2009-04-01T23:59:59.000Z

259

The nanogranular origin of concrete creep : a nanoindentation investigation of microstructure and fundamental properties of calcium-silicate-hydrates  

E-Print Network (OSTI)

With an annual per capita consumption of one cubic meter, concrete is the most manufactured material on Earth. But concrete subject to sustained load creeps, like chewing gum, at a rate that deteriorates the durability and ...

Vandamme, Matthieu

2008-01-01T23:59:59.000Z

260

Low Wind Speed Technology Phase I: Evaluation of Design and Construction Approaches for Economical Hybrid Steel/Concrete Wind Turbine Towers; BERGER/ABAM Engineers Inc.  

DOE Green Energy (OSTI)

This fact sheet describes a subcontract with BERGER/ABAM Engineers Inc. to study the economic feasibility of concrete and hybrid concrete/steel wind turbine towers.

Not Available

2006-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "rectangular precast concrete" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Effects of composition and exposure on the solar reflectance of Portland cement concrete  

Science Conference Proceedings (OSTI)

Increasing the solar reflectance (albedo) of a paved surface keeps it cooler in the sun, reducing convection of heat from pavement to air and thereby decreasing the ambient air temperature. Simulations of the influence of pavement albedo on air temperature in Los Angeles predict that increasing the albedo of 1,250 km2 of pavement by 0.25 would save cooling energy worth $15M yr-1, and reduce smog-related medical and lost-work expenses by $76M yr-1. Most sidewalks and a small fraction of roads and parking areas are paved with portland cement concrete, which can be made quite reflective through suitable choice of cement and aggregate. Variations with composition and environmental exposure of the albedos of portland cement concrete pavements were investigated through laboratory fabrication and exposure of 32 mixes of concrete. Twenty-four mixes yielded substandard, ''rough'' concretes due to high, unmet aggregate water demand. The albedos of the remaining eight ''smooth'' concrete mixes ranged from 0.41 to 0.77 (mean 0.59). Simulated weathering, soiling, and abrasion each reduced average concrete albedo (mean decreases 0.06, 0.05, and 0.19, respectively), though some samples became slightly more reflective through weathering or soiling. Simulated rain (wetting) strongly depressed the albedos of concretes (mean decrease 0.23) until their surfaces were dried. Concrete albedo grew as the cement hydration reaction progressed (mean increase 0.08), but stabilized within six weeks of casting. White-cement concretes were on average significantly more reflective than gray-cement concretes. The albedo of the most-reflective white-cement concrete was 0.18 to 0.39 higher than that of the most-reflective gray-cement concrete, depending on state of exposure. Concrete albedo generally correlated with cement albedo and sand albedo, and, after abrasion, with rock albedo. Cement albedo had a disproportionately strong influence on the reflectance of concrete. Efflorescence and surface carbonation whitened some gray-cement mixes.

Levinson, Ronnen; Akbari, Hashem

2001-12-21T23:59:59.000Z

262

HIGH-DENSITY CONCRETE WITH CERAMIC AGGREGATE BASED ON DEPLETED URANIUM DIOXIDE  

NLE Websites -- All DOE Office Websites (Extended Search)

DENSITY CONCRETE WITH CERAMIC AGGREGATE BASED ON DEPLETED URANIUM DENSITY CONCRETE WITH CERAMIC AGGREGATE BASED ON DEPLETED URANIUM DIOXIDE S.G. Ermichev, V.I. Shapovalov, N.V.Sviridov (RFNC-VNIIEF, Sarov, Russia) V.K. Orlov, V.M. Sergeev, A. G. Semyenov, A.M. Visik, A.A. Maslov, A. V. Demin, D.D. Petrov, V.V. Noskov, V. I. Sorokin, O. I. Uferov (VNIINM, Moscow, Russia) L. Dole (ORNL, Oak Ridge, USA) Abstract - Russia is researching the production and testing of concretes with ceramic aggregate based on depleted uranium dioxide (UO 2 ). These DU concretes are to be used as structural and radiation-shielded material for casks for A-plant spent nuclear fuel transportation and storage. This paper presents the results of studies aimed at selection of ceramics and concrete composition, justification of their production technology, investigation of mechanical properties, and chemical stability.

263

Lightweight concrete materials and structural systems for water tanks for thermal storage. Final report  

DOE Green Energy (OSTI)

Thermally efficient hot water storage tanks were designed, fabricated and evaluated. The tanks were made using cellular concrete at a nominal density of 100 lb/ft/sup 3/ for the structural elements and at a 30 lb/ft/sup 3/ density for the insulating elements. Thermal performance testing of the tanks was done using a static decay test since the test procedure specified in ASHRAE 94-77 was not experimentally practical. A series of composition modifications to the cellular concrete mix were investigated and the addition of alkaline resistant glass fibers was found to enhance the mechanical properties at no sacrifice in thermal behavior. Economic analysis indicated that cellular concrete provides a cost-effective insulating material. The total portability of the plant for producing cellular concrete makes cellular concrete amenable to on-site fabrication and uniquely adaptable to retrofit applications.

Buckman, R.W. Jr.; Elia, G.G.; Ichikawa, Y.

1980-12-01T23:59:59.000Z

264

Depth Profiles of Radionuclides Induced in Shielding Concrete of the 12 GeV Proton Accelerator Facility at KEK  

E-Print Network (OSTI)

Depth Profiles of Radionuclides Induced in Shielding Concrete of the 12 GeV Proton Accelerator Facility at KEK

Miura, T; Ishihama, S; Ohotsuka, N; Kunifuda, T

2000-01-01T23:59:59.000Z

265

Evaluation of Concrete Containing Fly Ash With High Carbon Content and/or Small Amounts of Wood  

Science Conference Proceedings (OSTI)

This report provides a comprehensive database of information on the impacts of the use of high carbon coal ashes and concretes with small amounts of wood ash on the performance of concretes. It is expected these data will support easing the restrictions on the use of high carbon ashes and any wood ash products in concrete in the ASTM standards.

1998-06-25T23:59:59.000Z

266

FIBRE REINFORCEMENT FOR SHRINKAGE CRACK CONTROL IN PRESTRESSED, PRECAST  

E-Print Network (OSTI)

. MILTENBERGER, J. Mater. Civil Eng. 11(1) (1999) 1. 42. R. ABDUL-RAHMAN and A. CHONG, in Proc. Drilling Con

Vecchio, Frank J.

267

Concrete Model Descriptions and Summary of Benchmark Studies for Blast Effects Simulations  

DOE Green Energy (OSTI)

Concrete is perhaps one of the most widely used construction materials in the world. Engineers use it to build massive concrete dams, concrete waterways, highways, bridges, and even nuclear reactors. The advantages of using concrete is that it can be cast into any desired shape, it is durable, and very economical compared to structural steel. The disadvantages are its low tensile strength, low ductility, and low strength-to-weight ratio. Concrete is a composite material that consists of a coarse granular material, or aggregate, embedded in a hard matrix of material, or cement, which fills the gaps between the aggregates and binds them together. Concrete properties, however, vary widely. The properties depend on the choice of materials used and the proportions for a particular application, as well as differences in fabrication techniques. Table 1 provides a listing of typical engineering properties for structural concrete. Properties also depend on the level of concrete confinement, or hydrostatic pressure, the material is being subjected to. In general, concrete is rarely subjected to a single axial stress. The material may experience a combination of stresses all acting simultaneously. The behavior of concrete under these combined stresses are, however, extremely difficult to characterize. In addition to the type of loading, one must also consider the stress history of the material. Failure is determined not only by the ultimate stresses, but also by the rate of loading and the order in which these stresses were applied. The concrete model described herein accounts for this complex behavior of concrete. It was developed by Javier Malvar, Jim Wesevich, and John Crawford of Karagozian and Case, and Don Simon of Logicon RDA in support of the Defense Threat Reduction Agency's programs. The model is an enhanced version of the Concrete/Geological Material Model 16 in the Lagrangian finite element code DYNA3D. The modifications that were made to the original model ensured that the material response followed experimental observations for standard uniaxial, biaxial, and triaxial tests for both tension and compression type loading. A disadvantage of using this material model, however, is the overwhelming amount of input that is required from the user. Therefore, the goal of this report is to provide future users with the tools necessary for successfully using this model.

Noble, C; Kokko, E; Darnell, I; Dunn, T; Hagler, L; Leininger, L

2005-07-21T23:59:59.000Z

268

ASTM STANDARD GUIDE FOR EVALUATING DISPOSAL OPTIONS FOR REUSE OF CONCRETE FROM NUCLEAR FACILITY DECOMMISSIONING  

SciTech Connect

Within the nuclear industry, many contaminated facilities that require decommissioning contain huge volumes of concrete. This concrete is generally disposed of as low-level waste at a high cost. Much of the concrete is lightly contaminated and could be reused as roadbed, fill material, or aggregate for new concrete, thus saving millions of dollars. However, because of the possibility of volumetric contamination and the lack of a method to evaluate the risks and costs of reusing concrete, reuse is rarely considered. To address this problem, Argonne National Laboratory-East (ANL-E) and the Idaho National Engineering and Environmental Laboratory teamed to write a ''concrete protocol'' to help evaluate the ramifications of reusing concrete within the U.S. Department of Energy (DOE). This document, titled the Protocol for Development of Authorized Release Limits for Concrete at U.S. Department of Energy Site (1) is based on ANL-E's previously developed scrap metal recycle protocols; on the 10-step method outlined in DOE's draft handbook, Controlling Release for Reuse or Recycle of Property Containing Residual Radioactive Material (2); and on DOE Order 4500.5, Radiation Protection of the Public and the Environment (3). The DOE concrete protocol was the basis for the ASTM Standard Guide for Evaluating Disposal Options for Concrete from Nuclear Facility Decommissioning, which was written to make the information available to a wider audience outside DOE. The resulting ASTM Standard Guide is a more concise version that can be used by the nuclear industry worldwide to evaluate the risks and costs of reusing concrete from nuclear facility decommissioning. The bulk of the ASTM Standard Guide focuses on evaluating the dose and cost for each disposal option. The user calculates these from the detailed formulas and tabulated data provided, then compares the dose and cost for each disposal option to select the best option that meets regulatory requirements. With this information, the reuse of concrete may be possible, thus reducing dose and decontamination and decommissioning costs. This paper outlines ten steps required to release concrete for reuse and discusses the disposal options covered in the ASTM Standard Guide.

Phillips, Ann Marie; Meservey, Richard H.

2003-02-27T23:59:59.000Z

269

ORNL_TM360_Concrete_NDE_Roadmap  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

60 60 Light Water Reactor Sustainability Nondestructive Evaluation for Concrete Research and Development Roadmap September 2012 Prepared by Dwight Clayton Michael Hileman DOCUMENT AVAILABILITY Reports produced after January 1, 1996, are generally available free via the U.S. Department of Energy (DOE) Information Bridge. Web site http://www.osti.gov/bridge Reports produced before January 1, 1996, may be purchased by members of the public from the following source. National Technical Information Service 5285 Port Royal Road Springfield, VA 22161 Telephone 703-605-6000 (1-800-553-6847) TDD 703-487-4639 Fax 703-605-6900 E-mail info@ntis.gov Web site http://www.ntis.gov/support/ordernowabout.htm Reports are available to DOE employees, DOE contractors, Energy Technology Data Exchange

270

Computational Design of Novel Multiscale Concrete Rheometers | Argonne  

NLE Websites -- All DOE Office Websites (Extended Search)

Suspended particles in a rheometer Suspended particles in a rheometer This simulation image shows suspended particles in a rheometer for NIST's proposed mortar SRM. The spheres, which are color coded by their starting location in the rheometer, are suspended in a cement paste with properties derived from NIST's cement paste SRM. Nicos Martys and Steven G. Satterfield, National Institute of Standards and Technology Computational Design of Novel Multiscale Concrete Rheometers PI Name: William George PI Email: wgeorge@nist.gov Institution: National Institute of Standards and Technology (NIST) Allocation Program: INCITE Allocation Hours at ALCF: 40 Million Year: 2014 Research Domain: Materials Science Understanding the mechanisms of dispersion or agglomeration of particulate matter in complex fluids, such as suspensions, is of technological

271

Mobile system for microwave removal of concrete surfaces  

DOE Patents (OSTI)

A method and apparatus are disclosed for the microwave removal of contaminated concrete surfaces. The apparatus comprises a housing adapted to pass over a support surface. The housing includes a waveguide for directing microwave energy to the surface at an angle maximizing absorption of microwave energy by the surface. The apparatus is further provided with a source of microwave energy operably associated with the waveguide, wherein the microwave energy has a frequency of between about 10.6 GHz and about 24 GHz and acts to remove the uppermost layer from the surface. The apparatus further includes a debris containment assembly comprising a vacuum assembly operably associated with the housing. The vacuum assembly is adapted to remove debris from the area adjacent the surface. 7 figs.

White, T.L.; Bigelow, T.S.; Schaich, C.R.; Foster, D. Jr.

1997-06-03T23:59:59.000Z

272

Mobile system for microwave removal of concrete surfaces  

DOE Patents (OSTI)

A method and apparatus for the microwave removal of contaminated concrete surfaces. The apparatus comprises a housing adapted to pass over a support surface. The housing includes a waveguide for directing microwave energy to the surface at an angle maximizing absorption of microwave energy by the surface. The apparatus is further provided with a source of microwave energy operably associated with the waveguide, wherein the microwave energy has a frequency of between about 10.6 GHz and about 24 GHz and acts to remove the uppermost layer from the surface. The apparatus further includes a debris containment assembly comprising a vacuum assembly operably associated with the housing. The vacuum assembly is adapted to remove debris from the area adjacent the surface.

White, Terry L. (Oak Ridge, TN); Bigelow, Timothy S. (Knoxville, TN); Schaich, Charles R. (Lenoir City, TN); Foster, Jr., Don (Knoxville, TN)

1997-01-01T23:59:59.000Z

273

High temperature concrete composites containing organosiloxane crosslinked copolymers  

DOE Patents (OSTI)

This invention relates to high temperature polymer concrete composites comprising about 10-30% by weight of a liquid monomer mixture consisting essentially of an organosiloxane polymer crosslinked with an olefinically unsaturated monomer selected from the group consisting of styrene, methyl methacrylate, trimethylolpropane trimethacrylate, triallyl cyanurate, n-phenylmalimide, divinyl benzene and mixtures theroef; and about 70-90% by weight of an inert inorganic filler system containing silica sand and preferably a member selected from the group consisting of portland cement, Fe.sub.2 O.sub.3, carbon black and mixtures thereof; and optionally a free radical initiator such as di-tert-butyl peroxide, azobisisobutyronitrile, benzoyl peroxide, lauryl peroxide and other organic peroxides to initiate crosspolymerization of the monomer mixture in the presence of the inorganic filler.

Zeldin, Arkady (Rego Park, NY); Carciello, Neal (Patchogue, NY); Kukacka, Lawrence (Port Jefferson, NY); Fontana, Jack (Shoreham, NY)

1980-01-01T23:59:59.000Z

274

Two-Phase Frictional Pressure Drop Multipliers for SUVA R-134a Flowing in a Rectangular Duct  

SciTech Connect

The adiabatic two-phase frictional multipliers for SUVA, R-134a flowing in a rectangular duct (with D{sub H} = 4.8 mm) have been measured for 3 nominal system pressures (0.9 MPa, 1.38 MPa and 2.41 MPa) and 3 nominal mass fluxes (510, 1020 and 2040 kg/m{sup 2}/s). The data is compared with several classical correlations to assess their predictive capabilities. The Lockhart-Martinelli model gives reasonable results at the lowest pressure and mass flux, near the operating range of most refrigeration systems, but gives increasingly poor comparisons as the pressure and mass flux is increased. The Chisholm B-coefficient model is found to best predict the data over the entire range of test conditions; however, there is significant disagreement at the highest pressure tested (with the model over predicting the data upwards of 100% for some cases). The data shows an increased tendency toward homogeneous flow as the pressure and flow rate are increased, and in fact the homogeneous model best predicts the bulk of the data at the highest pressure tested.

P Vassallo; K Keller

2004-12-13T23:59:59.000Z

275

Fly ash and concrete: a study determines whether biomass, or coal co-firing fly ash, can be used in concrete  

SciTech Connect

Current US national standards for using fly ash in concrete (ASTM C618) state that fly ash must come from coal combustion, thus precluding biomass-coal co-firing fly ash. The co-fired ash comes from a large and increasing fraction of US power plants due to rapid increases in co-firing opportunity fuels with coal. The fly ashes include coal fly ash, wood fly ash from pure wood combustion, biomass and coal co-fired fly ash SW1 and SW2. Also wood fly ash is blended with Class C or Class F to produce Wood C and Wood E. Concrete samples were prepared with fly ash replacing cement by 25%. All fly ash mixes except wood have a lower water demand than the pure cement mix. Fly ashes, either from coal or non coal combustion, increase the required air entraining agent (AEA) to meet the design specification of the mixes. If AEA is added arbitrarily without considering the amount or existence of fly ash results could lead to air content in concrete that is either too low or too high. Biomass fly ash does not impact concrete setting behaviour disproportionately. Switch grass-coal co-fired fly ash and blended wood fly ash generally lie within the range of pure coal fly ash strength. The 56 day flexure strength of all the fly ash mixes is comparable to that of the pure cement mix. The flexure strength from the coal-biomass co-fired fly ash does not differ much from pure coal fly ash. All fly ash concrete mixes exhibit lower chloride permeability than the pure cement mixes. In conclusion biomass coal co-fired fly ash perform similarly to coal fly ash in fresh and hardened concrete. As a result, there is no reason to exclude biomass-coal co-fired fly ash in concrete.

Wang, Shuangzhen; Baxter, Larry

2006-08-01T23:59:59.000Z

276

Instrumentation of a prestressed concrete containment vessel model  

Science Conference Proceedings (OSTI)

A series of static overpressurization tests of scale models of nuclear containment structures is being conducted by Sandia National Laboratories for the Nuclear Power Engineering Corporation of Japan and the U.S. Nuclear Regulatory Commission. At present, two tests are being planned: a test of a model of a steel containment vessel (SCV) that is representative of an improved, boiling water reactor (BWR) Mark II design; and a test of a model of a prestressed concrete containment vessel (PCCV). This paper discusses plans and the results of a preliminary investigation of the instrumentation of the PCCV model. The instrumentation suite for this model will consist of approximately 2000 channels of data to record displacements, strains in the reinforcing steel, prestressing tendons, concrete, steel liner and liner anchors, as well as pressure and temperature. The instrumentation is being designed to monitor the response of the model during prestressing operations, during Structural Integrity and Integrated Leak Rate testing, and during test to failure of the model. Particular emphasis has been placed on instrumentation of the prestressing system in order to understand the behavior of the prestressing strands at design and beyond design pressure levels. Current plans are to place load cells at both ends of one third of the tendons in addition to placing strain measurement devices along the length of selected tendons. Strain measurements will be made using conventional bonded foil resistance gages and a wire resistance gage, known as a {open_quotes}Tensmeg{close_quotes}{reg_sign} gage, specifically designed for use with seven-wire strand. The results of preliminary tests of both types of gages, in the laboratory and in a simulated model configuration, are reported and plans for instrumentation of the model are discussed.

Hessheimer, M.F.; Rightley, M.J. [Sandia National Labs., Albuquerque, NM (United States); Matsumoto, T. [Nuclear Power Engineering Corp., Tokyo (Japan)] [and others

1995-09-01T23:59:59.000Z

277

Evaluation and optimization of pervious concrete with respect to permeability and clogging  

E-Print Network (OSTI)

Although pervious concrete was first used in the nineteenth century, it has only recently begun to increase in popularity. As urban areas expand, the problems associated with runoff management have become more challenging. The focus on the negative environmental effects associated with pavement runoff has also increased. These two issues have spurred the recent interest in pervious concrete pavements.Pervious concrete, however, has deficiencies which limit its application as pavements. These limitations include low compressive strength, flexural strength, clogging, and other durability issues. The overall purpose of this project was to provide tools to evaluate and improve the durability and strength of pervious concrete such that it may be more confidently employed in urban roadways. The specific objectives of this project were to (a) investigate the effect of mixture design on strength of pervious concrete (including the effect of fibers), (b) evaluate effect of clogging materials on coefficient of permeability, (c) and investigate the use of the dynamic pressurization test to evaluate the durability of pervious concrete, (d) develop a simple model for predicting removal of clogging particles from pervious concrete pavement surface pores. This thesis documents the results of the laboratory testing, and presents recommendations for mixture proportioning. In addition, recommendations are provided for optimizing the balance between compressive strength and permeability.

Joung, Young

2008-12-01T23:59:59.000Z

278

Use of wastes derived from earthquakes for the production of concrete masonry partition wall blocks  

Science Conference Proceedings (OSTI)

Highlights: > Solved the scientific and technological challenges impeding use of waste rubble derived from earthquake, by providing an alternative solution of recycling the waste in moulded concrete block products. > Significant requirements for optimum integration on the utilization of the waste aggregates in the production of concrete blocks are investigated. > A thorough understanding of the mechanical properties of concrete blocks made with waste derived from earthquake is reported. - Abstract: Utilization of construction and demolition (C and D) wastes as recycled aggregates in the production of concrete and concrete products have attracted much attention in recent years. However, the presence of large quantities of crushed clay brick in some the C and D waste streams (e.g. waste derived collapsed masonry buildings after an earthquake) renders the recycled aggregates unsuitable for high grade use. One possibility is to make use of the low grade recycled aggregates for concrete block production. In this paper, we report the results of a comprehensive study to assess the feasibility of using crushed clay brick as coarse and fine aggregates in concrete masonry block production. The effects of the content of crushed coarse and fine clay brick aggregates (CBA) on the mechanical properties of non-structural concrete block were quantified. From the experimental test results, it was observed that incorporating the crushed clay brick aggregates had a significant influence on the properties of blocks. The hardened density and drying shrinkage of the block specimens decreased with an increase in CBA content. The use of CBA increased the water absorption of block specimens. The results suggested that the amount of crushed clay brick to be used in concrete masonry blocks should be controlled at less than 25% (coarse aggregate) and within 50-75% for fine aggregates.

Xiao Zhao [Department of Civil and Structural Engineering, Hong Kong Polytechnic University, Hung Hom, Kowloon (Hong Kong); Faculty of Architecture, Civil Engineering and Environment Engineering and Mechanics, Sichuan University (China); Ling, Tung-Chai; Kou, Shi-Cong [Department of Civil and Structural Engineering, Hong Kong Polytechnic University, Hung Hom, Kowloon (Hong Kong); Wang Qingyuan [Faculty of Architecture, Civil Engineering and Environment Engineering and Mechanics, Sichuan University (China); Poon, Chi-Sun, E-mail: cecspoon@polyu.edu.hk [Department of Civil and Structural Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon (Hong Kong)

2011-08-15T23:59:59.000Z

279

Models for estimation of service life of concrete barriers in low-level radioactive waste disposal  

SciTech Connect

Concrete barriers will be used as intimate parts of systems for isolation of low level radioactive wastes subsequent to disposal. This work reviews mathematical models for estimating the degradation rate of concrete in typical service environments. The models considered cover sulfate attack, reinforcement corrosion, calcium hydroxide leaching, carbonation, freeze/thaw, and cracking. Additionally, fluid flow, mass transport, and geochemical properties of concrete are briefly reviewed. Example calculations included illustrate the types of predictions expected of the models. 79 refs., 24 figs., 6 tabs.

Walton, J.C.; Plansky, L.E.; Smith, R.W. (EG and G Idaho, Inc., Idaho Falls, ID (USA))

1990-09-01T23:59:59.000Z

280

Carderock Tow Tank 2 | Open Energy Information  

Open Energy Info (EERE)

2 2 Overseeing Organization United States Naval Surface Warfare Center Hydrodynamic Testing Facility Type Tow Tank Length(m) 574.9 Beam(m) 15.5 Depth(m) 6.7 Water Type Freshwater Cost(per day) Contact POC Special Physical Features Carriage 2 is located on this basin Towing Capabilities Towing Capabilities Yes Maximum Velocity(m/s) 10.3 Wavemaking Capabilities Wavemaking Capabilities Yes Maximum Wave Height(m) 0.6 Maximum Wave Length(m) 12.2 Wave Period Range(s) 0.0 Current Velocity Range(m/s) 0.0 Programmable Wavemaking Yes Wavemaking Description Irregular waves with a spectrum resembling typical ocean wave patterns with appropriate scale reductions Wave Direction Uni-Directional Simulated Beach Yes Description of Beach The wave absorber spans the full width of the basin at the end opposite the wavemaker dome, the absorbers are a discontinuous 12 degree slope type made up of 12 permeable layers of rectangular precast concrete bar panels resting on an impermeable concrete slab supported by a structural steel framework, the center section of the absorber is of wood construction & can be raised and lowered as a unit to provide model access to and from the fitting-out dry dock located at the end of the basin.

Note: This page contains sample records for the topic "rectangular precast concrete" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Heat Transfer in Rectangular Channels (AR=2:1) of the Gas Turbine Blade at High Rotation Numbers  

E-Print Network (OSTI)

Gas turbine blade/vane cooling is obtained by circulating the high pressure air from compressor to the internal cooling passage of the blade/vane. Heat transfer and cooling effect in the rotating blade is highly affected by rotation. The typical rotation number for the aircraft engine is in the range of 0~0.25 and for the land based power generation turbine in the range of 0~05. Currently, the heat transfer data at high rotation numbers are limited. Besides, the investigation of heat transfer phenomena in the turn region, especially near hub portion is rare. This dissertation is to study the heat transfer in rectangular channels with turns in the tip or the hub portion respectively at high rotation numbers close to the engine condition. The dissertation experimentally investigates the heat transfer phenomena in a two-pass rectangular channel (AR=W/H=2:1) with a 180 degree sharp turn in the tip portion. The flow in the first passage is radial outward and after the turn in the second passage, the flow direction is radial inward. The hydraulic diameter (Dh) of the channel is 16.9 mm. Parallel square ribs with an attack angle (alpha) of 45 degrees are used on leading and trailing surfaces to enhance the heat transfer. The rib height-to-hydraulic diameter ratio (e/Dh) is 0.094. For the baseline smooth case and the case with rib pitch-to-height ratio (P/e) 10, channel orientation angles (beta) of 90 degrees and 135 degrees were tried to model the cooling passage in the mid and rear portion of the blade respectively. Two other P/e ratios of 5 and 7.5 were studied at beta=135 degrees to investigate their effect on heat transfer. The data are presented under high rotation numbers and buoyancy parameters by varying the Reynolds number (Re=10,000~40,000) and rotation speed (rpm=0~400). Corresponding rotation number and buoyancy parameter are ranged as 0~0.45 and 0~0.8 respectively. The dissertation also studies the heat transfer in a two-pass channel (AR=2:1) connected by a 180 degree U bend in the hub portion. The flow in the first passage is radial inward and after the U bend, the flow in the second passage is radial outward. The cross-section dimension of this channel is the same as the previous one. To increase heat transfer, staggered square ribs (e/Dh=0.094) are pasted on leading and trailing walls with an attack angle (alpha) of 45 degrees and pitch-to-height ratio (P/e) of 8. A turning vane in the shape of half circle (R=18.5 mm, t=1.6 mm) is used in the turn region to guide the flow for both smooth and ribbed cases. Channel orientation angles (beta) of 90 degrees and 135 degrees were taken for both smooth and ribbed cases. The heat transfer data were taken at high rotation numbers close to previous test section.

Lei, Jiang 1980-

2011-08-01T23:59:59.000Z

282

Concrete Company Aims Higher for More Wind Energy | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Concrete Company Aims Higher for More Wind Energy Concrete Company Aims Higher for More Wind Energy Concrete Company Aims Higher for More Wind Energy July 29, 2010 - 6:41pm Addthis The EnergySmart Jobs program is a three-pronged approach to creating “green jobs” for Californians while also increasing energy efficiency at businesses around the state. | File photo The EnergySmart Jobs program is a three-pronged approach to creating "green jobs" for Californians while also increasing energy efficiency at businesses around the state. | File photo Stephen Graff Former Writer & editor for Energy Empowers, EERE What does this mean for me? Tindall Corporation received $16.7 million in 48C tax credits to build new plant Kansas facility will manufacture concrete wind tower bases over 100 meters in height

283

Demonstration experience with an abrasive blasting technique for decontaminating concrete pads  

SciTech Connect

A demonstration was performed for decontaminating a radioactivity contaminated concrete pad with a portable abrasive blasting system. The system utilizes a rotating blast wheel that scours the concrete surface with metal abrasive. The metal abrasive, pulverized concrete dust, and contaminants rebound into a separator chamber. The reusable metal abrasive is recycled, and the pulverized media are removed to an integral dust collection system. The exhaust is HEPA filtered to minimize release of airborne contaminants. However, the technique had limited success in reducing contamination around the cracks and seams in the concrete where the higher activity levels of contamination were detected during the radiological survey before the cleanup. The technique can be successful and cost-effective in decontaminating large areas of low contamination; however, careful characterization and planning are necessary. 3 refs., 3 figs., 1 tabs.

Devgun, J.S. (Argonne National Lab., IL (USA)); Land, R.R. (Bechtel National, Inc., Oak Ridge, TN (USA)); Doane, R.W. (TMA/Eberline, Oak Ridge, TN (USA))

1990-01-01T23:59:59.000Z

284

Effects of moisture on debonding in FRP-retrofitted concrete systems  

E-Print Network (OSTI)

FRP (fiber reinforced polymer) retrofit systems for reinforced concrete (RC) structures have been widely used in the past 10 years, and numerous studies on its short-term debonding behavior have been conducted extensively. ...

Tuakta, Chakrapan, 1980-

2011-01-01T23:59:59.000Z

285

Assessment of FRP-confined concrete : understanding behavior and issues in nondestructive evaluation using radar  

E-Print Network (OSTI)

Increase in the use of fiber-reinforced polymer (FRP) composite materials for strengthening and retrofitting of concrete columns and bridge piers has urged the development of' an effective non-destructive evaluation (NDE) ...

Ortega, Jose Alberto, 1978-

2006-01-01T23:59:59.000Z

286

Concrete Company Aims Higher for More Wind Energy | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Concrete Company Aims Higher for More Wind Energy Concrete Company Aims Higher for More Wind Energy Concrete Company Aims Higher for More Wind Energy July 29, 2010 - 6:41pm Addthis The EnergySmart Jobs program is a three-pronged approach to creating “green jobs” for Californians while also increasing energy efficiency at businesses around the state. | File photo The EnergySmart Jobs program is a three-pronged approach to creating "green jobs" for Californians while also increasing energy efficiency at businesses around the state. | File photo Stephen Graff Former Writer & editor for Energy Empowers, EERE What does this mean for me? Tindall Corporation received $16.7 million in 48C tax credits to build new plant Kansas facility will manufacture concrete wind tower bases over 100 meters in height

287

Seismic Performance, Modeling, and Failure Assessment of Reinforced Concrete Shear Wall Buildings  

E-Print Network (OSTI)

Post- Tensioned Concrete Buildings, PEER Report 2011/104,RC shear walls in high-rise buildings, The Young ResearcherExtended 3D Analysis of Building Structures, Computers and

Tuna, Zeynep

2012-01-01T23:59:59.000Z

288

Tilt-up concrete panels : an investigation of flexural stresses and punching shear during lifting  

E-Print Network (OSTI)

Tilt-up construction is becoming more popular in the United States due to its ease of construction, reliability, and relatively low construction and maintenance costs. In its most typical form, a concrete panel is cast on ...

Bono, Matthew P. (Matthew Paul)

2011-01-01T23:59:59.000Z

289

Recommendations for the design of ultra-high performance concrete structures  

E-Print Network (OSTI)

New materials frequently require modifications or rewrites of existing construction codes. They may also need new methods for their manufacture and installation. DUCTAL, a new ultra-high performance concrete (UHPC) with ...

Davila, Ricardo S

2007-01-01T23:59:59.000Z

290

Monitoring the Durability Performance of Concrete in Nuclear Waste Containment. Technical Progress Report No. 3  

SciTech Connect

OAK-B135 Monitoring the Durability Performance of Concrete in Nuclear Waste Containment. Technical Progress Report No. 3(NOTE: Part II A item 1 indicates ''PAPER'', but a report is attached electronically)

Ulm, Franz-Josef

2000-03-31T23:59:59.000Z

291

A Novel Structural Assessment Technique to Prevent Damaged FRP-Wrapped Concrete Bridge Piers from Collapse  

E-Print Network (OSTI)

Repairing deteriorated concrete bridge piers using externally wrapped fiber reinforced polymer (FRP) composites have been proven as an effective approach. This technique has also been applied to low-rise building structures. ...

Buyukozturk, Oral

2009-01-01T23:59:59.000Z

292

Activities in Support of Continuing the Service of Nuclear Power Plant Safety-Related Concrete Structures  

SciTech Connect

Nuclear power plant (NPP) concrete structures are described. In-service inspection and testing requirements in the U.S. are summarized. The license renewal process in the U.S. is outlined and its current status provided. Operating experience related to performance of the concrete structures is presented. Basic components of a program to manage aging of the concrete structures are identified and described: (1) Degradation mechanisms, damage models, and material performance; (2) Assessment and remediation: i.e., component selection, in- service inspection, non-destructive examinations, and remedial actions; and (3) Estimation of performance at present or some future point in time: i.e., application of structural reliability theory to the design and optimization of in-service inspection/maintenance strategies, and determination of the effects of degradation on plant risk. Finally, areas are noted where additional research would be of benefit to aging management of nuclear power plant concrete structures.

Naus, Dan J [ORNL

2014-01-01T23:59:59.000Z

293

Activities in Support of Continuing the Service of Nuclear Power Plant Safety-Related Concrete Structures  

SciTech Connect

Nuclear power plant concrete structures are described. In-service inspection and testing requirements in the U.S. are summarized. The license renewal process in the U.S. is outlined and its current status provided. Operating experience related to performance of the concrete structures is presented. Basic components of a program to manage aging of the concrete structures are identified and described: degradation mechanisms, damage models, and material performance; assessment and remediation (i.e., component selection, in-service inspection, non-destructive examinations, and remedial actions); and estimation of performance at present or some future point in time (i.e., application of structural reliability theory to the design and optimization of in-service inspection/maintenance strategies, and determination of the effects of degradation on plant risk). Finally, areas are noted where additional research would be of benefit to aging management of nuclear power plant concrete structures.

Naus, Dan J [ORNL

2010-01-01T23:59:59.000Z

294

Site Selection for Concrete Batch Plant to Support Plutonium Disposition Facilities at the Savannah River Site  

Science Conference Proceedings (OSTI)

WSRC conducted a site selection study to identify, assess, and rank candidate sites for an onsite concrete batch plant at the Savannah River Site in the vicinity of F-Area.

Wike, L.D.

2001-06-15T23:59:59.000Z

295

External Prestressed Carbon Fiber-Reinforced Polymer Straps for Shear Enhancement of Concrete  

E-Print Network (OSTI)

, nonlaminated, carbon fiber-reinforced polymer (CFRP) straps as external shear reinforcement for concrete. Experiments were carried out on an unstrengthened control beam and beams strengthened with external CFRP straps. It was found that the ultimate load...

Lees, Janet M.; Winistrfer, A. U.; Meier, U.

2002-10-15T23:59:59.000Z

296

Concrete Shield Performance of the VSC-17 Spent Nuclear Fuel Cask  

Science Conference Proceedings (OSTI)

The VSC-17 Spent Nuclear Fuel Storage Cask was surveyed for degradation of the concrete shield by radiation measurement, temperature measurement, and ultrasonic testing. No general loss of shielding function was identified.

Koji Shirai

2006-04-01T23:59:59.000Z

297

Material worlds : [de]constructing the ethos of concrete in Mumbai  

E-Print Network (OSTI)

What can a building material tell us about a city? As the most widely used structural building material in the world, reinforced cement concrete shapes the urban form of several of our largest megacities Sao Paulo, Cairo, ...

Shah, Priyanka (Priyanka Dinesh)

2008-01-01T23:59:59.000Z

298

Design and analysis of a concrete modular housing system constructed with 3D panels  

E-Print Network (OSTI)

An innovative modular house system design utilizing an alternative concrete residential building system called 3D panels is presented along with an overview of 3D panels as well as relevant methods and markets. The proposed ...

Sarcia, Sam Rhea, 1982-

2004-01-01T23:59:59.000Z

299

Turbulent particle deposition in a rectangular chamber: Study of the effect of particle size and ventilation regimes  

SciTech Connect

The interaction of aerosol particles with wall surfaces is important in modeling their behavior. This interaction is usually represented in theoretical models as a loss term. The loss rate is the rate at which particles deposit or react with the surfaces. This loss term is important in many branches of aerosol science including human health and indoor air quality. Increased surface deposition usually means lower concentrations of airborne particles and hence, lower exposure to the inhabitants. If the efficiency of the particle deposition is influenced by factors other than the particle size, such as a natural convection of the air, this has to be taken into account to evaluate the results. In this research, test aerosol sized from 15 nm to 3 {micro}m are produced by several different aerosol generators; the gas burner, the Collison nebulizer, the condensation aerosol generator, the orifice atomizer and the Vibrating Orifice Aerosol Generator (VOAG). A rectangular chamber whose dimensions are 75 x 75 x 180 cm{sup 3} was used in this study. The particles were injected into the chamber, with a known ventilation and the concentration decay was monitored by the Ultrafine Condensation Particle Counter (UCPC) and Optical Particle Counter (OPC). During the measurement, the air inside the chamber is moved by natural convection and ventilation effect. The results shows that the particle loss rate under the higher air exchange rate is larger and this is not only due to air exchange itself but also the wall deposition. The theoretical model presented by Benes and Holub (1996) agree with the experimental data better than the Crump and Seinfield (1981) model with the hypothesis of Plandtl`s mixing length. 118 refs.

Nomura, Yoshio

1996-04-01T23:59:59.000Z

300

Laboratory Evaluation of the Effects of Potassium Acetate Deicing Chemicals on the Performance of Concrete  

Science Conference Proceedings (OSTI)

Recent evidence suggests that the most commonly used salt for snow and ice control on airfield pavements, potassium acetate (KAc), may adversely impact long-term durability of concrete. This report provides interim findings from a study on effects of potassium acetate on performance of concrete. The main objectives of this program are as follows: Determine whether potassium acetate solution exacerbates alkali-silica reaction (ASR) under field conditions and in the laboratory under simulated field and ac...

2010-12-09T23:59:59.000Z

Note: This page contains sample records for the topic "rectangular precast concrete" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Program on Technology Innovation: Assessment of Needs for Concrete Research in the Energy Industry  

Science Conference Proceedings (OSTI)

The objective of this report is to compile information on issues pertaining to the degradation of concrete structures in the energy industry and to provide guidance in areas where research and development efforts might be needed. The state of these structures, known as concrete degradation, the life management approach, and challenges with new structures are discussed. In each case, a set of suggestions for further research is proposed. Finally, a set of recommendations for the overall needs of short-, m...

2010-12-20T23:59:59.000Z

302

THE UTILIZATION OF GAMMA RAYS IN TESTING THE SHRINKAGE IN HARD CONCRETE  

SciTech Connect

A linear relationship was established experimentally between the residual intensity of an x-ray beam which hss been sent through the concrete mixure under investigation (estimsted from the number of pulses registered by a Geiger-Mueller counter) and the degree of shrinkage (bulk density) of the mixture. It is proposed to use Co/sup 60/ in the evaluation of the degree of shrinkage of concrete.

Soroker, V.; Vaynshtok, I.; Kayser, L.

1956-01-01T23:59:59.000Z

303

LWR Sustainability: Assessment of Aging of Nuclear Power Plant Safety Related Concrete Strutures  

Science Conference Proceedings (OSTI)

Current regulatory testing and inspection requirements are reviewed and a summary of degradation experience is presented. Techniques commonly used to inspect NPP concrete structures to assess and quantify age-related degradation are summarized. An approach for conduct of condition assessments of structures in NPPs is presented. Criteria, based primarily on visual indications, are provided for use in classification and assessment of concrete degradation. Materials and techniques for repair of degraded structures are generally discussed.

Graves III, Herman [U.S. Nuclear Regulatory Commission; Naus, Dan J [ORNL

2013-01-01T23:59:59.000Z

304

CANMET/Industry Research Consortium on Alkali-Aggregate Reactivity in Concrete  

Science Conference Proceedings (OSTI)

The alkali-silica reaction (ASR) is a deleterious chemical reaction that can result in the deterioration of concrete structures. This report presents the results of a research and development study, funded by a broadly-based multi-national industry consortium, that is developing an engineering database on the long-term effectiveness of fly ash and other supplementary cementing materials (SCMs) in counteracting ASR in concrete.

2001-12-11T23:59:59.000Z

305

The Role of High Calcium Fly Ashes in Controlling Alkali-Silica Reactions in Concrete  

Science Conference Proceedings (OSTI)

The alkali-silica reaction (ASR) is a deleterious chemical reaction that can result in the deterioration of concrete structures. This report builds upon the results of a research and development study, funded by a broadly-based multi-national industry consortium, that is developing an engineering database on the long-term effectiveness of Class F fly ash and other supplementary cementing materials (SCMs) in counteracting ASR in concrete.

2002-11-20T23:59:59.000Z

306

RESTORING A DAMAGED 16-YEAR -OLD INSULATING POLYMER CONCRETE DIKE OVERLAY: REPAIR MATERIALS AND TECHNOLOGIES.  

Science Conference Proceedings (OSTI)

The objective of this program was to design and formulate organic polymer-based material systems suitable for repairing and restoring the overlay panels of insulating lightweight polymer concrete (ILPC) from the concrete floor and slope wall of a dike at KeySpan liquefied natural gas (LNG) facility in Greenpoint, Brooklyn, NY, just over sixteen years ago. It also included undertaking a small-scale field demonstration to ensure that the commercial repairing technologies were applicable to the designed and formulated materials.

SUGAMA,T.

2007-01-01T23:59:59.000Z

307

Concrete--polymer materials for geothermal applications. Progress report No. 6, July--September 1975  

DOE Green Energy (OSTI)

Materials are needed for handling hot brine and steam at temperatures greater than 200/sup 0/C. Thermal stability of styrene--acrylonitrile (ACN)--trimethylolpropane trimethylacrylate (TMPTMA) polymers was studied. Compressive strengths of polymer concretes using styrene--TMPTMA or styrene--ACN--TMPTMA were determined after exposure to hot brine. Field tests of concrete-polymer materials at The Geysers and other geothermal sites are under way and are described. Radioinduced polymerization was used as well as chemical polymerization. (DLC)

Not Available

1975-10-01T23:59:59.000Z

308

Molten Corium Concrete Interactions: Advanced Containment Experiments (ACE) Project: Summary Report  

Science Conference Proceedings (OSTI)

Seven successful large-scale molten corium concrete interaction (MCCI) experiments produced ablation rate measurements for a range of concrete types. In addition, the experiments yielded measurements of the release fractions for low-volatility fission products and control materials for prototypical accident conditions. This report summarizes the 41 reports, which provide the detailed results of the experiments, and presents the main conclusions of the project.

1993-12-01T23:59:59.000Z

309

Concrete Shield Performance of the VSC-17 Spent Nuclear Fuel Cask  

Science Conference Proceedings (OSTI)

In 2003, representatives from the Central Research Institute of Electric Power Industry (CRIEPI) requested development of a project with the objective of determining the performance of a concrete spent nuclear fuel storage cask. Radiation and environmental effects may cause chemical alteration of the concrete that could result in excessive cracking, spalling, and loss of compressive strength. The Idaho National Laboratory (INL) project team and CRIEPI representatives identified the Ventilated Storage Cask (VSC-17) spent nuclear fuel storage cask as a candidate to study cask performance, because it had been used to store fuel as part of a dry cask storage demonstration project for more than 15 years. The project involved investigating the properties of the concrete shield. INL performed a survey of the cask in the summers of 2003 and 2004. Preliminary cask evaluations performed in 2003 indicated that the cask has no visual degradation. However, a 4-5 mrem/hr step-change in the radiation levels about halfway up the cask and a localized hot spot beneath an upper air vent indicate that there may be variability in the density of the concrete or localized cracking. In 2005, INL and CRIEPI scientists performed additional surveys on the VSC-17 cask. This document summarizes the methods used on the VSC-17 to evaluate the cask for compressive strength, concrete cracking, concrete thickness, and temperature distribution.

Sheryl L. Morton; Philip L. Winston; Toshiari Saegusa; Koji Shirai; Akihiro Sasahara; Takatoshi Hattori

2006-04-01T23:59:59.000Z

310

Relationship between Frequency of RFID Tags and Its Ability to Penetrate Fresh Concrete  

E-Print Network (OSTI)

The concrete maturity method can be utilized to determine in situ strength of concrete. It uses the temperature of concrete to determine a maturity index that can then be used to determine strength of concrete. However, monitoring the concrete temperature using thermocouples brings up a wiring issue, which is not advisable in an equipment and human intensive area like a construction site. One of the ways to get around this wiring issue is to use Radio Frequency Identification (RFID) technology, which is capable of transmitting information wirelessly. Previous research implemented using ultra high frequency RFID tags embedded in fresh concrete found that water could be the impediment for transmitting RFID signal from within concrete during early stages of curing. From literature it was found that lower the frequency, better the chances of the wave penetrating water. The objective of the research was to figure out whether the frequency of RFID tags has any relationship with the readability of RFID tags embedded in fresh concrete. For this investigation, low frequency, high frequency, and ultra high frequency RFID tags were tested within fresh concrete to see any difference between tags in terms of transmitting information. This experiment was carried out in a controlled space to reduce the number of variables affecting the experiment outcome. The low frequency, high frequency, and ultra high frequency RFID tags were placed within 2 in x 3 in x 2 in wooden formwork at a depth of 4 in, 8 in, and 12 in. Ready mix concrete was poured into the formwork and 3 concrete cubes were cast with the tags embedded within them. Readers that could be connected to a laptop were used to monitor and collect the time at which these RFID tags can be detected. The test showed that the RFID signals from the low frequency tags at all depths were detected as soon as concrete was poured. The Ultra High Frequency tags placed at the 4" level could be detected 15 minutes after concrete was poured. The UHF tags at the 8" level could be detected after 30 minutes. The UHF tags at the 12" level took on an average 2 hours to be detected from the vicinity of the formwork. The greater the depth at which the ultra high frequency tag was buried the longer it took for it to be detected. The high frequency tags could be detected only at the 4" level. The reason the performance of the HF card degraded in concrete could be because it uses an aluminum foil antenna which is more susceptible to the environment changing the relative permeability. A copper wire antenna could have fared better in this condition, increasing the chances of detecting the tag. Moreover a passive tag was used. The read range and chances of detection could have been increased had an active tag been used. The power of the reader that was used was also very less which might have contributed to the tag not being detected. Among the tags that were used in the experiment it was found that low frequency tags was the tag that could be detected the earliest after concrete was poured into the forms. However, the maximum read range of the tag observed in the experiment was 20" which is too small a distance to be used on an actual construction site.

Sridharan, Rajasekaran

2010-05-01T23:59:59.000Z

311

Periodic Inspections of Concrete-Armored Coastal Structures  

E-Print Network (OSTI)

information on the long-term structural performance of selected concrete-armored navigation structures to their environment. Inspections of coastal structures at Ofu Harbor, American Samoa; Nawiliwili, Laupahoehoe, and Kahului Harbors, HI; and Manasquan Inlet, NJ, are discussed herein. The response of stone-armored coastal structures to their environment was presented in ERDC/CHL CHETN-III-65. OVERVIEW: In the Periodic Inspections work unit of the Monitoring Completed Navigation Projects (MCNP) Program, selected coastal navigation structures are periodically monitored to gain an understanding of their long-term structural response. Periodic data sets are evaluated to improve knowledge in design, construction, and maintenance of both existing and proposed coastal navigation projects, and will help avoid repeating past designs that have failed and/or resulted in high maintenance costs. Low-cost remote sensing tools and techniques, with limited ground truthing surveys, are the primary inspection tools used in the periodic monitoring efforts. Most periodic inspections consist of capturing above-water conditions of the structures at periodic intervals using high-resolution aerial photography. Structural changes (primary armor unit movement) are quantified through photogrammetric techniques. When a coastal structure is photographed at low

Robert R. Bottin

2003-01-01T23:59:59.000Z

312

Method of lining a vertical mine shaft with concrete  

DOE Patents (OSTI)

The apparatus includes a cylindrical retainer form spaced inwardly of the wall of the shaft by the desired thickness of the liner to be poured and having overlapping edges which seal against concrete flow but permit the form to be contracted to a smaller circumference after the liner has hardened and is self-supporting. A curb ring extends downwardly and outwardly toward the shaft wall from the bottom of the retainer form to define the bottom surface of each poured liner section. An inflatable toroid forms a seal between the curb ring and the shaft wall. A form support gripper ring having gripper shoes laterally extendable under hydraulic power to engage the shaft wall supports the retainer form, curb ring and liner until the newly poured liner section becomes self-supporting. Adjusting hydraulic cylinders permit the curb ring and retainer form to be properly aligned relative to the form support gripper ring. After a liner section is self-supporting, an advancing system advances the retainer form, curb ring and form support gripper ring toward a shaft boring machine above which the liner is being formed. The advancing system also provides correct horizontal alignment of the form support gripper ring.

Eklund, James D. (Mattawa, WA); Halter, Joseph M. (Richland, WA); Rasmussen, Donald E. (Spokane, WA); Sullivan, Robert G. (Richland, WA); Moffat, Robert B. (Federal Way, WA)

1981-01-01T23:59:59.000Z

313

The Damaging Effects of Earthquake Excitation on Concrete Cooling Towers  

SciTech Connect

Reinforced concrete cooling towers of hyperbolic shell configuration find widespread application in utilities engaged in the production of electric power. In design of critical civil infrastructure of this type, it is imperative to consider all the possible loading conditions that the cooling tower may experience, an important loading condition in many countries is that of the earthquake excitation, whose influence on the integrity and stability of cooling towers is profound. Previous researches have shown that the columns supporting a cooling tower are sensitive to earthquake forces, as they are heavily loaded elements that do not possess high ductility, and understanding the behavior of columns under earthquake excitation is vital in structural design because they provide the load path for the self weight of the tower shell. This paper presents the results of a finite element investigation of a representative 'dry' cooling tower, using realistic horizontal and vertical acceleration data obtained from the recent and widely-reported Tabas, Naghan and Bam earthquakes in Iran. The results of both linear and nonlinear analyses are reported in the paper, the locations of plastic hinges within the supporting columns are identified and the ramifications of the plastic hinges on the stability of the cooling tower are assessed. It is concluded that for the (typical) cooling tower configuration analyzed, the columns that are instrumental in providing a load path are influenced greatly by earthquake loading, and for the earthquake data used in this study the representative cooling tower would be rendered unstable and would collapse under the earthquake forces considered.

Abedi-Nik, Farhad [SADRA Institute of Higher Education, Tehran (Iran, Islamic Republic of); Sabouri-Ghomi, Saeid [K.N.T University of Technology, Tehran (Iran, Islamic Republic of)

2008-07-08T23:59:59.000Z

314

Aspect ratio effect on heat transfer in rotating two-pass rectangular channels with smooth walls and ribbed walls  

E-Print Network (OSTI)

This study experimentally investigates the effects of rotation, the buoyancy force, and the channel aspect ratio on heat transfer in two-pass rotating rectangular channels. The experiments are conducted with two surface conditions: smooth walls and 45?? angled ribbed walls. The channel aspect ratios include 4:1, 2:1, 1:1, 1:2 and 1:4. Four Reynolds numbers are studied: 5000, 10000, 25000 and 40000. The rotation speed is fixed at 550 rpm for all tests, and for each channel, two channel orientations are studied: 90?? and 45?? or 135??, with respect to the plane of rotation. Rib turbulators are placed on the leading and trailing walls of the channels at an angle of 45?? to the flow direction. The ribs have a 1.59 by 1.59 mm square cross section, and the rib pitch-to-height ratio (P/e) is 10 for all tests. The effects of the local buoyancy parameter and channel aspect ratio on the regional Nusselt number ratio are presented. Pressure drop data are also measured for both smooth and ribbed channels in rotating and non-rotating conditions. The results show that increasing the local buoyancy parameter increases the Nusselt number ratio on the trailing surface and decreases the Nusselt number ratio on the leading surface in the first pass for all channels. However, the trend of the Nusselt number ratio in the second pass is more complicated due to the strong effect of the 180?? turn. Results are also presented for this critical turn region of the two-pass channels. In addition to these regions, the channel averaged heat transfer, friction factor, and thermal performance are determined for each channel. With the channels having comparable Nusselt number ratios, the 1:4 channel has the superior thermal performance because it incurs the least pressure penalty. In this study, the author is able to systematically analyze, correlate, and conclude the thermal performance comparison with the combination of rotation effects on five different aspect ratio channels with both smooth walls and rib turbulated walls.

Fu, Wen-Lung

2005-05-01T23:59:59.000Z

315

The effect of jet velocity ratio on aerodynamics of a rectangular slot-burner in the presence of cross-flow  

Science Conference Proceedings (OSTI)

In a typical coal-fired power station boiler the ignition and the combustion of the fuel is largely controlled by burner aerodynamics. An experimental and numerical study of the rectangular slot-burners widely used on power stations in Victoria, Australia has been conducted to improve understanding of jet development within the boiler. The 1:15 scale model burner consisted of a central (primary) rectangular fuel nozzle with two (secondary) rectangular air jets positioned above and below it. The burner jets entered the measurement vessel at an angle of 60 deg to the wall. A cross-flow jet was attached to the wall of the vessel to simulate the recirculation prevalent in power station boilers. Experiments were conducted using a primary to cross-flow jet velocity ratio ({phi}) of 1.0 and secondary to primary jet velocity ratios ({phi}) of 1.0 and 3.0. Laser Doppler Anemometry (LDA) was used to measure mean and turbulent velocity components in the near field and downstream regions of the jets. Cross-flow significantly influenced the near field flow development from the slot-burner by deviating both primary and secondary jets from their geometric axes towards the wall. The degree of deviation was greater for {phi} = 1.0 since the higher velocity secondary jets increased the overall momentum of the primary jet for {phi} = 3.0. A numerical investigation of the rectangular slot-burner was also performed. First, the numerical results were validated against the experimental results and then visualization of the developing flow field was used to reveal the finer details of the cross-flow/burner jet interaction. Agreement between numerical and experimental jet features was good, although the numerical results predicted a primary jet that was marginally too narrow. Also the predicted downstream behaviour for {phi} = 3.0 deviated more significantly from experimental observation. Using the SST turbulence model, the numerical results suggested that a twin vortex was generated behind the initial region of the primary jet and this would aid in mixing of gas and fuel between primary and secondary jets. (author)

Ahmed, S. [CSIRO Manufacturing and Materials Technology, Highett VIC-3190 (Australia); Hart, J.; Naser, J. [School of Engineering and Industrial Sciences, Swinburne University of Technology, Hawthorn VIC-3122 (Australia); Nikolov, J.; Solnordal, C.; Yang, W. [CSIRO Minerals, Clayton, VIC-3169 (Australia)

2007-11-15T23:59:59.000Z

316

Preliminary investigation on the suitablity of using fiber reinforced concrete in the construction of a hazardous waste disposal vessel  

Science Conference Proceedings (OSTI)

There are certain hazardous wastes that must be contained in an extremely secure vessel for transportation and disposal. The vessel, among other things, must be able to withstand relatively large impacts without rupturing. Such containment vessels therefore must be able to absorb substantial amounts of energy during an impact and still perform their function. One of the impacts that the vessel must withstand is a 30-foot fall onto an unyielding surface. For some disposal scenarios it is proposed to encase the waste in a steel enclosure which is to be surrounded by a thick layer of concrete which, in turn, is encased by a relatively thin steel shell. Tests on concrete in compression and flexure, including static, dynamic and impact tests, have shown that low modulus concretes tend to behave in a less brittle manner than higher modulus concretes. Tests also show that fiber reinforced concretes have significantly greater ductility, crack propagation resistance and toughness than conventional concretes. Since it is known that concrete is a reasonably brittle material, it is necessary to do impact tests on sample containment structures consisting of thin-walled metal containers having closed ends which are filled with concrete, grout, or fiber reinforced concrete. This report presents the results of simple tests aimed at observing the behavior of sample containment structures subjected to impacts due to a fall from 30 feet. 8 figs., 4 tabs.

Ramey, M.R.; Daie-e, G.

1988-07-01T23:59:59.000Z

317

Encapsulation of phase change materials in concrete masonry construction. Progress report No. 1, August 1977--February 1978  

DOE Green Energy (OSTI)

The improvement of thermal energy storage capacity of potential building materials by incorporation of phase change materials (PCM's) is being explored. Both inorganic salt hydrates and organic systems are potentially useful PCM's for encapsulation in concrete, polymer concrete, and/or polymer-impregnated concrete matrices. It is felt at this time that most PCM's melting at or above 40/sup 0/C can be encapsulated in large quantities in polymer concrete. Methods relating to the encapsulation of lower melting materials in various matrices are currently being studied.

Sansone, M J

1978-01-01T23:59:59.000Z

318

Thermal Removal Of Tritium From Concrete And Soil To Reduce Groundwater Impacts  

SciTech Connect

Legacy heavy-water moderator operations at the Savannah River Site (SRS) have resulted in the contamination of equipment pads, building slabs, and surrounding soil with tritium. At the time of discovery the tritium had impacted the shallow (< 3-m) groundwater at the facility. While tritium was present in the groundwater, characterization efforts determined that a significant source remained in a concrete slab at the surface and within the associated vadose zone soils. To prevent continued long-term impacts to the shallow groundwater a CERCLA non-time critical removal action for these source materials was conducted to reduce the leaching of tritium from the vadose zone soils and concrete slabs. In order to minimize transportation and disposal costs, an on-site thermal treatment process was designed, tested, and implemented. The on-site treatment consisted of thermal detritiation of the concrete rubble and soil. During this process concrete rubble was heated to a temperature of 815 deg C (1,500 deg F) resulting in the dehydration and removal of water bound tritium. During heating, tritium contaminated soil was used to provide thermal insulation during which it's temperature exceeded 100 deg C (212 deg F), causing drying and removal of tritium. The thermal treatment process volatiles the water bound tritium and releases it to the atmosphere. The released tritium was considered insignificant based upon Clean Air Act Compliance Package (CAP88) analysis and did not exceed exposure thresholds. A treatability study evaluated the effectiveness of this thermal configuration and viability as a decontamination method for tritium in concrete and soil materials. Post treatment sampling confirmed the effectiveness at reducing tritium to acceptable waste site specific levels. With American Recovery and Reinvestment Act (ARRA) funding three additional treatment cells were assembled utilizing commercial heating equipment and common construction materials. This provided a total of four units to batch treat concrete rubble and soil. Post treatment sampling verified that the activity in the treated soil and concrete met the treatment standards for each medium which allowed the treated concrete rubble and soil to be disposed of on site as backfill. During testing and operations a total of 1,261-m{sup 3} (1,650-yd{sup 3}) of contaminated concrete and soils were treated with an actual incurred cost of $3,980,000. This represents a unit treatment cost of $3,156/m{sup 3} ($2,412/yd{sup 3}). In 2011 the project was recognized with an e-Star Sustainability Award by DOE's Office of Environmental Management.

Jackson, Dennis G.; Blount, Gerald C.; Wells, Leslie H.; Cardoso-Neto, Joao E.; Kmetz, Thomas F.; Reed, Misty L.

2012-12-04T23:59:59.000Z

319

Advancement of Erosion Testing, Modeling, and Design of Concrete Pavement Subbase Layers  

E-Print Network (OSTI)

Concrete pavement systems have great capacity to provide long service lives; however, if the subbase layer is improperly designed or mismanaged, service life would be diminished significantly since the subbase layer performs many important roles in a concrete pavement system. The erosion of material beneath a concrete slab is an important performance-related factor that if applied to the selection of base materials can enhance the overall design process for concrete pavement systems. However, erosion of the subbase has not been included explicitly in analysis and design procedures since there is not a well accepted laboratory test and related erosion model suitable for design. Previous erosion test methods and erosion models are evaluated in terms of their utility to characterize subbase materials for erosion resistance. With this information, a new test configuration was devised that uses a Hamburg wheel-tracking device for evaluating erodibility with respect to the degree of stabilization and base type. Test devices, procedures, and results are explained and summarized for application in mechanistic design processes. A proposed erosion model is calibrated by comparing erosion to lab test results and LTPP field performance data. Subbase design guidelines are provided with a decision flowchart and a design assistant spread sheet for the economical and sustainable design of concrete pavement subbase layers by considering many design factors that affect the performance of the subbase.

Jung, Youn Su

2010-08-01T23:59:59.000Z

320

Evaluation of allowable stresses for high strength concrete prestressed bridge girders  

E-Print Network (OSTI)

High strength concrete (HSC) is regularly used for prestressed bridge girders in Texas and other states. The American Concrete Institute (ACI) Committee 363 (1997) defines HSC as concrete with a compressive strength exceeding 6,000 psi (41 MPa) produced without using exotic materials or techniques. The design provisions for the design of prestressed concrete members according to the AASHTO Standard and LRFD Specifications are based on mechanical properties determined for normal strength concrete (NSC). Therefore, there is a need to evaluate these specifications based on the properties of HSC. The main objective of this research is to evaluate the allowable tensile stresses for HSC prestressed bridge girders. The effects of field curing conditions on the compressive strength and the flexural tensile strength of HSC were determined. The HSC mixtures tested in this study are representative of mixtures used in Phase 1 of this research program (Chompreda 2001). The plant-produced samples from the earlier study were lab cured after the first day (approximately 24 hours). Necessary strength adjustment factors are needed to account for the effect of field curing conditions. These factors were determined for representative HSC mixtures and applied to the compressive and flexural strength data from Phase 1 in order to evaluate the potential to increase the limiting allowable stresses. A parametric study was conducted to evaluate the impact of a modified tensile stress limit on the design of typical HSC prestressed girders. The safety of the modified tensile stress limit was evaluated by applying structural reliability theory.

Moutassem, Fayez

2003-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "rectangular precast concrete" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Standard Guide for Evaluating Disposal Options for Concrete from Nuclear Facility Decommissioning  

E-Print Network (OSTI)

1.1 This standard guide defines the process for developing a strategy for dispositioning concrete from nuclear facility decommissioning. It outlines a 10-step method to evaluate disposal options for radioactively contaminated concrete. One of the steps is to complete a detailed analysis of the cost and dose to nonradiation workers (the public); the methodology and supporting data to perform this analysis are detailed in the appendices. The resulting data can be used to balance dose and cost and select the best disposal option. These data, which establish a technical basis to apply to release the concrete, can be used in several ways: (1) to show that the release meets existing release criteria, (2) to establish a basis to request release of the concrete on a case-by-case basis, (3) to develop a basis for establishing release criteria where none exists. 1.2 This standard guide is based on the Protocol for Development of Authorized Release Limits for Concrete at U.S. Department of Energy Sites, (1) from ...

American Society for Testing and Materials. Philadelphia

2002-01-01T23:59:59.000Z

322

Cleareye In-Ground and In-Concrete DIV Inspections: FY11 Final Report  

DOE Green Energy (OSTI)

This report summarizes the results of a series of feasibility testing studies for in-ground and in-concrete imaging/detection technologies including radar imaging and acoustic time-of flight method. The objectives of this project are: (1) Design Information Verification (DIV) Tools for In-Concrete Inspections - To determine the feasibility of using holographic radar imaging (HRI), radar imaging, and acoustic time-of-flight (TOF) non-destructive evaluation technologies to detect, locate and identify pipes and voids embedded in standard-density and high-density concrete walls that typify those the IAEA will need to verify during field inspections; (2) DIV Tools for In-Ground Inspections - To determine the feasibility of using HRI and radar imaging non-destructive evaluation technologies to detect, locate, and identify objects buried at various depths made of various materials (metal, plastic, wood, and concrete) and representing geometries that typify those the IAEA will need to verify during field inspections; and (3) Based on the results of the studies, recommend the next steps needed to realize fieldable tools for in-concrete and in-ground inspections (including detection of deeply buried polyvinyl chloride [PVC] pipes) that employ the technologies shown to be feasible.

Braatz, Brett G.; Tedeschi, Jonathan R.; Denslow, Kayte M.; Morra, Marino; Knopik, Clint D.; Severtsen, Ronald H.; Jones, Anthony M.; Lechelt, Wayne M.; McMakin, Douglas L.; Good, Morris S.; Sorensen, Jerry B.; Hall, Thomas E.

2012-01-23T23:59:59.000Z

323

Gaseous mercury release during steam curing of aerated concretes that contain fly ash and activated carbon sorbent  

Science Conference Proceedings (OSTI)

Gaseous mercury released from aerated concrete during both presteam curing at 25{sup o}C and steam curing at 80{sup o}C was measured in controlled laboratory experiments. Mercury release originated from two major components in the concrete mixture: (1) class F coal fly ash and (2) a mixture of the fly ash and powdered activated carbon onto which elemental mercury was adsorbed. Mercury emitted during each curing cycle was collected on iodated carbon traps in a purge-and-trap arrangement and subsequently measured by cold-vapor atomic fluorescence spectrometry. Through 3 h of presteam curing, the release of mercury from the freshly prepared mixture was less than 0.03 ng/kg of concrete. Releases of total mercury over the 21 h steam curing process ranged from 0.4 to 5.8 ng of mercury/kg of concrete and depended upon mercury concentrations in the concrete. The steam-cured concrete had a higher mercury release rate (ng kg{sup -1} h{sup -1}) compared to air-cured concrete containing fly ash, but the shorter curing interval resulted in less total release of mercury from the steam-cured concrete. The mercury flux from exposed concrete surfaces to mercury-free air ranged from 0.77 to 11.1 ng m{sup -2} h{sup -1}, which was similar to mercury fluxes for natural soils to ambient air of 4.2 ng m{sup -2} h{sup -1} reported by others. Less than 0.022% of the total quantity of mercury present from all mercury sources in the concrete was released during the curing process, and therefore, nearly all of the mercury was retained in the concrete. 31 refs., 4 figs., 2 tabs.

Danold W. Golightly; Chin-Min Cheng; Ping Sun; Linda K. Weavers; Harold W. Walker; Panuwat Taerakul; William E. Wolfe [Ohio State University, Columbus, OH (United States). Department of Civil and Environmental Engineering and Geodetic Science

2008-09-15T23:59:59.000Z

324

Application of Nonlinear Elastic Resonance Spectroscopy For Damage Detection In Concrete: An Interesting Story  

SciTech Connect

Nonlinear resonance ultrasound spectroscopy experiments conducted on concrete cores, one chemically and mechanically damaged by alkali-silica reactivity, and one undamaged, show that this material displays highly nonlinear wave behavior, similar to many other damaged materials. They find that the damaged sample responds more nonlinearly, manifested by a larger resonant peak and modulus shift as a function of strain amplitude. The nonlinear response indicates that there is a hysteretic influence in the stress-strain equation of state. Further, as in some other materials, slow dynamics are present. The nonlinear response they observe in concrete is an extremely sensitive indicator of damage. Ultimately, nonlinear wave methods applied to concrete may be used to guide mixing, curing, or other production techniques, in order to develop materials with particular desired qualities such as enhanced strength or chemical resistance, and to be used for damage inspection.

Byers, Loren W. [Los Alamos National Laboratory; Ten Cate, James A. [Los Alamos National Laboratory; Johnson, Paul A. [Los Alamos National Laboratory

2012-06-28T23:59:59.000Z

325

AN EXPERIMENTAL EVALUATION OF THE RADIATION PROTECTION AFFORDED BY A LARGE MODERN CONCRETE OFFICE BUILDING  

SciTech Connect

An experimental study was made to determine the effective shielding provided by a modern reinforced-concrete office building (AEC Headquarters building) from nuclear fall-out. Pocket ionization chambers were used for measurement of the radiation-field strength. Fall-out was simulated with distributed and point-source configurations of Co/sup 60/ and Ir/sup 192/ sources. Four typical sections were selected for study, and experiments were performed on each. These included an external wing with exposed basement walls and an external wing with a buried basement. Roof studies were made on an internal wing with a full basement and on the east end of wing A, which has a thin-roof construction. The thick-roof construction of 8 in. of concrete and 2 in. of rigid insulation covers all the building except the east end of wing A, which has 4 in. of concrete and 2 in. of insulation. (auth)

Batter, J.F. Jr.; Kaplan, A.L.; Clarke, E.T.

1959-05-01T23:59:59.000Z

326

Aging Management of Nuclear Power Plant Concrete Structures - Overview and Suggested Research Topics  

SciTech Connect

Nuclear power plant concrete structures are described and their operating experience noted. Primary considerations related to management of their aging are noted and an indication of their status provided: degradation mechanisms, damage models, and material performance; assessment and remediation (i.e., component selection, in-service inspection, nondestructive examinations, and remedial actions); and estimation of performance at present or some future point in time (i.e., application of structural reliability theory to the design and optimization of in-service inspection/maintenance strategies, and determination of the effects of degradation on plant risk). Several activities are identified that provide background information and data on areas of concern with respect to nondestructive examination of nuclear power plant concrete structures: inspection of thick-walled, heavily-reinforced sections, basemats, and inaccessible areas of the containment metallic pressure boundary. Topics are noted where additional research would be of benefit to aging management of nuclear power plant concrete structures.

Naus, Dan J [ORNL

2008-01-01T23:59:59.000Z

327

Assessment of durability performance of "Early-Opening-to-Traffic" Portland Cement Concrete pavement and patches  

E-Print Network (OSTI)

This study relates the assessment of durability to ''early-opening-to-traffic'' (EOT) portland cement concrete (PCC). Several factors were identified relative to the performance of EOT PCC. Each of these factors was considered in terms of freeze-thaw, shrinkage, chemical attack, abrasion resistance, fatigue life, volumetric expansion, practicality, and concrete costs. The assessment discusses material combinations, mixture designs, and construction practices on performance. A computer program using utility decision theory was applied in evaluating the parameters. Promising combinations of the above factors were determined based on the existing knowledge of material combinations used for EOT PCC, coupled with our understanding of the potentials of high performance concrete (HPC) for this type of application.

Shrestha, Pradhumna Babu

1999-01-01T23:59:59.000Z

328

ANALYTICAL RESULTS FOR MOX COLEMANITE CONCRETE SAMPLES RECEIVED ON NOVEMBER, 2013  

SciTech Connect

The Mixed Oxide Fuel Fabrication Facility (MFFF) will use colemanite bearing concrete neutron absorber panels credited with attenuating neutron flux in the criticality design analyses and shielding operators from radiation. The Savannah River National Laboratory (SRNL) is tasked with measuring the total density, partial hydrogen density, and partial boron density of the colemanite concrete. SRNL received two samples of colemanite concrete for analysis on November 21, 2013. The average total density of each of the samples measured by the ASTM method C 642, the average partial hydrogen density was measured using method ASTM E 1131, and the average partial boron density of each sample was measured according to ASTM C 1301. For all the samples tested, the total density and the boron partial density met or exceeded the specified limit. None of the samples met the lower limit for hydrogen partial density.

Reigel, M.

2013-12-18T23:59:59.000Z

329

ANALYTICAL RESULTS FOR MOX COLEMANITE CONCRETE SAMPLES RECEIVED ON SEPTEMBER 4, 2013  

SciTech Connect

The Mixed Oxide Fuel Fabrication Facility (MFFF) will use colemanite bearing concrete neutron absorber panels credited with attenuating neutron flux in the criticality design analyses and shielding operators from radiation. The Savannah River National Laboratory (SRNL) is tasked with measuring the total density, partial hydrogen density, and partial boron density of the colemanite concrete. SRNL received three samples of colemanite concrete for analysis on September 4, 2013. The average total density of each of the samples measured by the ASTM method C 642, the average partial hydrogen density was measured using method ASTM E 1131, and the average partial boron density of each sample was measured according to ASTM C 1301. The lower limits and measured values for the total density, hydrogen partial density, and boron partial density are presented. For all the samples tested, the total density and the boron partial density met or exceeded the specified limit. None of the samples met the lower limit for hydrogen partial density.

Reigel, M.

2013-09-24T23:59:59.000Z

330

A novel technique for the production of cool colored concrete tile and  

NLE Websites -- All DOE Office Websites (Extended Search)

A novel technique for the production of cool colored concrete tile and A novel technique for the production of cool colored concrete tile and asphalt shingle roofing products Title A novel technique for the production of cool colored concrete tile and asphalt shingle roofing products Publication Type Journal Article Year of Publication 2010 Authors Levinson, Ronnen M., Hashem Akbari, Paul Berdahl, Kurt Wood, Wayne Skilton, and Jerry Petersheim Journal Solar Energy Materials and Solar Cells Volume 94 Start Page 946 Issue 6 Pagination 946-954 Date Published 06/2010 Keywords asphalt shingle, concrete tile, Cool colored roof, Cool Colored Roofs, cool roofs, Heat Island, Polyvinylidene fluoride, Solar reflectance, surface roughness Abstract The widespread use of solar-reflective roofing materials can save energy, mitigate urban heat islands and slow global warming by cooling the roughly 20% of the urban surface that is roofed. In this study we created prototype solar-reflective nonwhite concrete tile and asphalt shingle roofing materials using a two-layer spray coating process intended to maximize both solar reflectance and factory-line throughput. Each layer is a thin, quick-drying, pigmented latex paint based on either acrylic or a poly(vinylidene fluoride)/acrylic blend. The first layer is a titanium dioxide rutile white basecoat that increases the solar reflectance of a gray-cement concrete tile from 0.18 to 0.79, and that of a shingle surfaced with bare granules from 0.06 to 0.62. The second layer is a "cool" color topcoat with weak near-infrared (NIR) absorption and/or strong NIR backscattering. Each layer dries within seconds, potentially allowing a factory line to pass first under the white spray, then under the color spray.

331

Pull-out and bond degradation of steel rebars in ECE concrete  

SciTech Connect

It is demonstrated in this study that application of electrochemical chloride extraction (ECE) to reinforced concrete alters the pull-out strength and bond between the embedded high strength steel (HSS) and surrounding concrete. Concrete cubes were case using two chloride ion concentrations of 1.7% and 3.0% by weight of cement respectively, and reinforced axially with a central plain steel bar. Two cathodic current densities were used for the ECE studies, with 0.1M sodium borate electrolyte solution and inert titanium anode mesh. Axial pull-out tests were carried out within 24 hours of terminating treatment to investigate the differences in bond stress and bar slip behavior. ECE treated specimens showed significant reductions in pull-out strength, with the degradation in bond being dependent on the applied cathodic current density and initial chloride contamination. At an impressed current density of 3.0 A/m{sup 2}, the 1.7% Cl{sup {minus}} ions specimens showed about 58% loss in bond strength compared with about 44% for specimens premixed with 3.0% Cl{sup {minus}} ion. The bond strength reduction at an impressed current density of 1.0 A/m{sup 2} was about half the reduction at current density of 3.0 A/m{sup 2}. It is predicted the softening effect of the alkali ions on the cement silicate hydrates around the steel-concrete interface will have severe effect on concrete structures reinforced with HSS irrespective of their stress state. Also, concrete structures containing steel rebars with substantial corrosion product coverage are likely to experience pronounced cathodic disbondment during ECE application and within a few days of terminating the treatment.

Ihekwaba, N.M.; Hope, B.B.; Hansson, C.M. [Queen`s Univ., Kingston, Ontario (Canada)

1996-02-01T23:59:59.000Z

332

ENERGY STAR Focus on Energy Efficiency in Ready Mix Concrete Manufacturing  

NLE Websites -- All DOE Office Websites (Extended Search)

Ready Mix Concrete Ready Mix Concrete Manufacturing Secondary menu About us Press room Contact Us Portfolio Manager Login Facility owners and managers Existing buildings Commercial new construction Industrial energy management Small business Service providers Service and product providers Verify applications for ENERGY STAR certification Design commercial buildings Energy efficiency program administrators Commercial and industrial program sponsors Associations State and local governments Federal agencies Tools and resources Training In this section Get started with ENERGY STAR Make the business case Build an energy management program Measure, track, and benchmark Tools for benchmarking energy management practices Tools for tracking and benchmarking facility energy performance ENERGY STAR Energy Performance Indicators for plants

333

Experiments with structural concrete blocks which double as solar air heaters. Final report  

DOE Green Energy (OSTI)

Because concrete is a low cost, low energy content material, and because many buildings have unobstructed south-facing walls, the concept of an air heating structural block was evolved. Four configurations are described, two routinely available from concrete block manufacturers, and two specially designed. Test walls were evaluated heating ambient air in a single pass, so the temperature difference was low. With that reservation, there was little difference between any of the configurations (one of the special designs was best) or between the blocks and conventional solar air heaters.

Payne, P.R.; Brown, J.P.

1979-01-01T23:59:59.000Z

334

Use of Class C Fly Ash in High-Volume Fly Ash Concrete Applications  

Science Conference Proceedings (OSTI)

Although the use of fly ash in concrete is a well-established practice, the volume of high-calcium Class C ash used lags behind that of low-calcium Class F ash. Because Class C may be the only type of ash produced in some western states, this disparity can significantly limit its use potential. The literature results presented in this report represent the first phase of a longer term research effort to provide technical information supporting the increased use of Class C ash in concrete applications.

2007-09-24T23:59:59.000Z

335

Radiolytic gas generation in concrete made with incinerator ash containing transuranium nuclides  

DOE Green Energy (OSTI)

The effects of various factors on H/sub 2/ generation by alpha radiolysis of concrete containing TRU incinerator ash were studied. Methods for reducing H/sub 2/ generation were investigated. Samples of Portland and high-alumina cement containing up to 30% calcined ash (dry basis) were doped with /sup 238/PuO/sub 2/. Gas pressures were measured as a function of radiation dose; gas compositions were determined. Gas yields were calculated in terms of G values (molecules produced per 100 eV of alpha energy absorbed). These yields were used to estimate pressures in containers of radioactive concrete waste during storage. 4 figures.

Bibler, N.E.

1979-01-01T23:59:59.000Z

336

Development and Performance Evaluation of High Temperature Concrete for Thermal Energy Storage for Solar Power Generation  

SciTech Connect

Thermal energy can be stored by the mechanism of sensible or latent heat or heat from chemical reactions. Sensible heat is the means of storing energy by increasing the temperature of the solid or liquid. Since the concrete as media cost per kWhthermal is $1, this seems to be a very economical material to be used as a TES. This research is focused on extending the concrete TES system for higher temperatures (500 ?ºC to 600 ?ºC) and increasing the heat transfer performance using novel construction techniques. To store heat at high temperature special concretes are developed and tested for its performance. The storage capacity costs of the developed concrete is in the range of $0.91-$3.02/kWhthermal Two different storage methods are investigated. In the first one heat is transported using molten slat through a stainless steel tube and heat is transported into concrete block through diffusion. The cost of the system is higher than the targeted DOE goal of $15/kWhthermal The increase in cost of the system is due to stainless steel tube to transfer the heat from molten salt to the concrete blocks.The other method is a one-tank thermocline system in which both the hot and cold fluid occupy the same tank resulting in reduced storage tank volume. In this model, heated molten salt enters the top of the tank which contains a packed bed of quartzite rock and silica sand as the thermal energy storage (TES) medium. The single-tank storage system uses about half the salt that is required by the two-tank system for a required storage capacity. This amounts to a significant reduction in the cost of the storage system. The single tank alternative has also been proven to be cheaper than the option which uses large concrete modules with embedded heat exchangers. Using computer models optimum dimensions are determined to have an round trip efficiency of 84%. Additionally, the cost of the structured concrete thermocline configuration provides the TES capacity cost of $33.80$/kWhthermal compared with $30.04/kWhthermal for a packed-bed thermocline (PBTC) configuration and $46.11/kWhthermal for a two-tank liquid configuration.

R. Panneer Selvam, Micah Hale and Matt strasser

2013-03-31T23:59:59.000Z

337

CO2 and cost optimization of reinforced concrete footings using a hybrid big bang-big crunch algorithm  

Science Conference Proceedings (OSTI)

A procedure is developed for the design of reinforced concrete footings subjected to vertical, concentric column loads that satisfies both structural requirements and geotechnical limit states using a hybrid Big Bang-Big Crunch (BB-BC) algorithm. The ... Keywords: Big Bang-Big Crunch optimization, Computer aided design, Optimization, Reinforced concrete, Spread footings, Structural design, Sustainable design

Charles V. Camp; Andrew Assadollahi

2013-08-01T23:59:59.000Z

338

Journal of Materials Education Vol. 33 (1-2): 37 -52 (2011) POLYMER CONCRETES: A DESCRIPTION AND METHODS FOR  

E-Print Network (OSTI)

limitations, including low tensile strength, poor environmental durability (resistance to freeze-thaw bond strength (bonding to previously existing concrete); increased freeze-thaw resistance; high as Polymer concrete (PCt) and boast several advantages such as higher strength and a shorter curing process

North Texas, University of

339

Comparison of coupled and decoupled modal approaches in seismic analysis of concrete gravity dams in time domain  

Science Conference Proceedings (OSTI)

Different methods are available for dynamic analysis of concrete dams. Among these, modal approach is highly popular due to the efficiency of the method. This becomes more significant if the response is to be calculated for several earthquake ground ... Keywords: Concrete gravity dam, Coupled modes, Decoupled modal approach, Dynamic analysis

Ali Samii; Vahid Lotfi

2007-09-01T23:59:59.000Z

340

Interim report on concreted uranium fines and chips billet curing tests: a basis for resuming shipment of concreted uranium scrap billets  

SciTech Connect

Through extensive testing and analyses of the concretion process, billets and shipping conditions, it has been determined that properly cured concreted billets can be safely shipped to National Lead Company of Ohio (NLO), Fernald. During curing, billets will be dried for 26 days prior to shipment with the last 10 days between 54 to 66/sup 0/C (130 to 150/sup 0/F). Such dried billets can withstand temperatures up to 85/sup 0/C (185/sup 0/F). The maximum billet temperature that can be expected to occur in shipment is 50/sup 0/C (123/sup 0/F). Thus, the drying cycle becomes a burning test at temperatures which the billets will not reach during shipment to NLO.

Weakley, E.A.

1980-05-02T23:59:59.000Z

Note: This page contains sample records for the topic "rectangular precast concrete" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Overview of Activities in U.S. Related to Continued Service of Nuclear Power Plant Concrete Structures  

SciTech Connect

Safety-related nuclear power plant concrete structures are described and commentary on continued service assessments of these structures is provided. In-service inspection and testing requirements in the U.S. are summarized. The license renewal process in the U.S. is outlined and its current status noted. A summary of operating experience related to U.S. nuclear power plant concrete structures is presented. Several candidate areas are identified where additional research would be of benefit to aging management of NPP concrete structures. Finally current ORNL activities related to aging-management of concrete structures are outlined: development of operating experience database, application of structural reliability theory, and compilation of elevated temperature concrete material property data and information.

Naus, Dan J [ORNL

2011-01-01T23:59:59.000Z

342

Comparison of artificial neural network and fuzzy logic models for prediction of long-term compressive strength of silica fume concrete  

Science Conference Proceedings (OSTI)

In this study, an artificial neural network (ANN) and fuzzy logic (FL) study were developed to predict the compressive strength of silica fume concrete. A data set of a laboratory work, in which a total of 48 concretes were produced, was utilized in ... Keywords: Compressive strength, Concrete, Fuzzy logic, Neural networks, Silica fume

Fatih zcan; Cengiz D. Ati?; Okan Karahan; Erdal Uncuo?lu; Harun Tanyildizi

2009-09-01T23:59:59.000Z

343

Eastgate seen from the south-east, in front of Harare's glass and concrete towers  

E-Print Network (OSTI)

Eastgate seen from the south-east, in front of Harare's glass and concrete towers #12;Eastgate officesEastgate offices Level two #12;Sections showing the passive cooling system #12;Cooling the office the degree of internal cooling achieved during April 1998 #12;· The termitary model · The termitary is an i f

Behmer, Spencer T.

344

Fly ash properties and mercury sorbent affect mercury release from curing concrete  

Science Conference Proceedings (OSTI)

The release of mercury from concrete containing fly ashes from various generator boilers and powdered activated carbon sorbent used to capture mercury was measured in laboratory experiments. Release of gaseous mercury from these concretes was less than 0.31% of the total quantity of mercury present. The observed gaseous emissions of mercury during the curing process demonstrated a dependency on the organic carbon content of the fly ash, with mercury release decreasing with increasing carbon content. Further, lower gaseous emissions of mercury were observed for concretes incorporating ash containing activated carbon sorbent than would be expected based on the observed association with organic carbon, suggesting that the powdered activated carbon more tightly binds the mercury as compared to unburned carbon in the ash. Following the initial 28-day curing interval, mercury release diminished with time. In separate leaching experiments, average mercury concentrations leached from fly ash concretes were less than 4.1 ng/L after 18 h and 7 days, demonstrating that less than 0.02% of the mercury was released during leaching. 25 refs., 4 figs., 5 tabs.

Danold W. Golightly; Chin-Min Cheng; Linda K. Weavers; Harold W. Walker; William E. Wolfe [State University, Columbus, OH (United States). Department of Civil and Environmental Engineering and Geodetic Science

2009-04-15T23:59:59.000Z

345

Service life of the reinforced concrete bridge deck in corrosive environments: A soft computing system  

Science Conference Proceedings (OSTI)

In the recent years, the soft computing techniques are increasingly applied in many fields of civil engineering due to their capabilities in computation and knowledge processing. In this paper, a soft computing system is developed to estimate the service ... Keywords: ?-Level optimization, Concrete bridge, Corrosion, Fuzzy random, Fuzzy system, Service life

Jafar Sobhani; Ali Akbar Ramezanianpour

2011-06-01T23:59:59.000Z

346

ESTIMATES FOR RELEASE OF RADIONUCLIDES FROM POTENTIALLY CONTAMINATED CONCRETE AT THE HADDAM NECK NUCLEAR PLANT.  

Science Conference Proceedings (OSTI)

Decommissioning of the Haddam Neck Nuclear Power Plant operated by Connecticut Yankee is in progress. Figure 1 shows a schematic of the Containment Building and Spent Fuel Pool (SFP) Building. Consideration is being given to leaving some subsurface concrete from the Containment, Spent Fuel and certain other buildings in place following NRC license termination. Characterization data of most of these structures show small amounts of residual contamination. The In-Core Sump area of the Containment Building has shown elevated levels of tritium, Co-60, Fe-55, and Eu-152 and lesser quantities of other radionuclides due to neutron activation of the concrete in this area. This analysis is provided to determine levels of residual contamination that will not cause releases to the groundwater in excess of the acceptable dose limits. The objective is to calculate a conservative relationship between the radionuclide concentration of subsurface concrete and the maximum groundwater concentration (pCi/L) for the concrete that may remain following license termination at Connecticut Yankee.

SULLIVAN, T.

2004-09-15T23:59:59.000Z

347

Sequentially linear analysis of shear critical reinforced concrete beams without shear reinforcement  

Science Conference Proceedings (OSTI)

Analyzing brittle structures with nonlinear finite element analysis is frequently attended with numerical problems. As an alternative method sequentially linear analysis could be utilized, resulting in the avoidance of convergence and bifurcation problems. ... Keywords: Brittle failure behavior, Cracking, Reinforced concrete, Sequentially linear analysis, Shear critical beam, Shear retention

A. T. Slobbe; M. A. N. Hendriks; J. G. Rots

2012-03-01T23:59:59.000Z

348

Properties of concrete paving blocks made with waste marble Osman Gencela,f,*, Cengiz Ozelb  

E-Print Network (OSTI)

Education 9, 201e227. Richardson, A., Coventry, K., Bacon, J., 2011. Freeze/thaw durability of concrete decreases with increasing marble content while freeze-thaw durability and abrasive wear resistance increase in the mixture. Table 4 Relative strength loss of blocks after freeze-thaw cycles (%). Code Strength loss (%) A0

North Texas, University of

349

Characterization of design parameters for fiber reinforced polymer composite reinforced concrete systems  

E-Print Network (OSTI)

Corrosion of steel reinforcement in concrete structures results in significant repair and rehabilitation costs. In the past several years, new fiber reinforced polymer (FRP) reinforcing bars have been introduced as an alternative to steel reinforcing bars. Several national and international organizations have recently developed standards based on preliminary test results. However, limited validation testing has been performed on the recommendations of these standards. High variability of the tensile properties, degradation of tensile strength, direct shear capacity, predicted deflections due to creep, cracking behavior of FRP-reinforced concrete flexural members, bond behavior and development length, and effects of thermal expansion on cracking of FRP reinforced concrete have all been reported, but are areas that need further investigation and validation. The objective of this study is to evaluate the characteristics of glass FRP reinforcing bars and provide recommendations on the design and construction of concrete structures containing these bar types with regard to the areas described. The recently developed ACI 440 design guidelines were analyzed and modifications proposed.

Aguiniga Gaona, Francisco

2003-12-01T23:59:59.000Z

350

VANESA: a mechanistic model of radionuclide release and aerosol generation during core debris interactions with concrete  

Science Conference Proceedings (OSTI)

This document describes a model, called VANESA, of the release of radionuclides and generation of aerosol accompanying reactor core melt interactions with structural concrete. The document also serves as a user's manual for an implementation of the VANESA model as a computer code. The technical bases for the VANESA model are reviewed. Mechanical generation of aerosols as bubbles burst at melt surfaces or as a result of liquid entrainment is considered. A description of these processes based on data for gas-sparged water systems is included in the VANESA model. Some limiting solutions to the problem of the competitive processes of nucleation of particles from vapor, condensation of vapors on surfaces, and coagulation of particles are examined. From these examinations an approximate model of the aerosol particle size produced during core debris interactions with concrete is devised. The attenuation of aerosol emission during core debris/concrete interactions by an overlying water pool is discussed. The document concludes with a description of a computer code implementation of the VANESA model. This implementation of the model was used in recent assessments of the behavior of radionuclides during severe reactor accidents. Comparisons of the predictions of radionuclide release during core debris/concrete interactions obtained with the VANESA model and with older models are presented.

Powers, D.A.; Brockmann, J.E.; Shiver, A.W.

1986-07-01T23:59:59.000Z

351

Uplift Pressures, Shear Strengths, and Tensile Strengths for Stability Analysis of Concrete Gravity Dams: Volume 1  

Science Conference Proceedings (OSTI)

Using generic values in stability analyses of existing concrete dams can result in expensive and unnecessary remedial work. The information in this report will help dam owners predict dam stability under extreme loading conditions and identify the conditions that control uplift pressure distributions at study dams.

1992-08-01T23:59:59.000Z

352

Guidelines for Drilling and Testing Core Samples at Concrete Gravity Dams  

Science Conference Proceedings (OSTI)

Regulatory agencies for dam safety often require stability data on concrete and foundation conditions--data obtained by testing core samples and taking various site measurements. These guidelines offer field-proven methods for compiling reliable results, with adequate documentation to support utility claims.

1989-05-01T23:59:59.000Z

353

Implementation Activities supporting the International Technology Scan on Long-Life concrete Pavements.  

E-Print Network (OSTI)

Implementation Plan (STIP) recommendations. The requested implementation support will be on a task order basis. The STIP recommendations are summarized below as identified in the draft STIP plan. Long-Life Concrete Pavements STIP - Initial Recommendations for Implementation Version 7, dated October 13, 2006 The long

354

Program on Technology Innovation: Chloride Attack-Induced Aging of Concrete Structures in the Energy Industry  

Science Conference Proceedings (OSTI)

Corrosion of embedded steel elements (reinforcement, liner, pre- or post-tensioning device) is a major cause of structure dysfunction resulting in large maintenance and repair costs worldwide. This report focuses on chloride attackinduced aging of concrete structures in the energy industry. Chloride attack is a common aging issue caused by marine environment, the extensive ...

2012-11-30T23:59:59.000Z

355

Effect of Corrosion on the Seismic Response of a Single-Bent, Reinforced Concrete Bridge  

E-Print Network (OSTI)

The effect of corrosion on a single-bent, reinforced concrete (RC) bridge subject to seismic loading is the primary focus of this research. This work attempts to determine the effects of decreasing rebar diameter and concrete cover spalling on the strength and stiffness of the RC bridge. The application of these results to the field of historic preservation will also be explored. Through the use of static and dynamic analyses, this research shows that the effects of corrosion only have a slight influence on the seismic fragility of the RC bridge. The loss of three inches of concrete cover from the bridge column is shown to have a greater effect on the strength and stiffness of the bridge than decreasing the rebar diameter by 10%. The deformation capacity and demand both increase for bridges with reduced reinforcing steel and concrete cover; however, the capacity increases to a greater degree than the demand. The seismic fragility of the bridge based on deformation criteria is greatest for the pristine structure, and it decreases as the level of damage increases. Future work should include verifying the hysteretic behavior by accounting for reinforcement slip caused by a loss of bond.

Harvat, Jessica

2009-05-01T23:59:59.000Z

356

Modeling of an Unbonded CFRP Strap Shear Retrofitting System for Reinforced Concrete Beams  

E-Print Network (OSTI)

, ?w is the crack angle in the web, Acf is the area of the flange contributing to shear friction and ?f is the crack angle in the flange. The effective concrete areas Acw and Acf as proposed by Tozser and Loov (1999) are illustrated in Fig. 3...

Hoult, Neil A.; Lees, Janet M.

2009-03-06T23:59:59.000Z

357

Standard Test Method for Half-Cell Potentials of Uncoated Reinforcing Steel in Concrete  

E-Print Network (OSTI)

1.1 This test method covers the estimation of the electrical corrosion potential of uncoated reinforcing steel in field and laboratory concrete, for the purpose of determining the corrosion activity of the reinforcing steel. 1.2 This test method is limited by electrical circuitry. Concrete surface in building interiors and desert environments lose sufficient moisture so that the concrete resistivity becomes so high that special testing techniques not covered in this test method may be required (see 5.1.4.1). Concrete surfaces that are coated or treated with sealers may not provide an acceptable electrical circuit. The basic configuration of the electrical circuit is shown in Fig. 1. 1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It ...

American Society for Testing and Materials. Philadelphia

2009-01-01T23:59:59.000Z

358

Life cycle model for evaluating the sustainability of concrete infrastructure systems  

E-Print Network (OSTI)

by the Department of Energy (USDOE 2004). A 4% discount rate was used for all construction activities. In addition. Carbon dioxide emissions from the global cement industry. Annual Reviews of Energy and the Envi- ronment. The model is applied to two alternative concrete bridge deck designs: one a conventional steel re- inforced

Lepech, Michael D.

359

Hybrid Simulation of the Seismic Response of Squat Reinforced Concrete Shear Walls  

E-Print Network (OSTI)

K. et al. , 2009. Update to ASCE/SEI 41 Concrete Provisions,Proceedings of the 2nd ASCE-EM D Specialty Conference on11.9, ACI 318-08 21.9, and ASCE 43-05. These are described

Whyte, Catherine Alexandra

2012-01-01T23:59:59.000Z

360

Effect of superficial insulation on roller-compacted concrete dams in cold regions  

Science Conference Proceedings (OSTI)

Superficial insulation is often used to prevent cracking of concrete dams located in cold regions. In this study, surface temperatures with and without heat insulation during the overwintering period are calculated. Using the material properties of roller-compacted ... Keywords: Superficial crack, Superficial insulation, Temperature difference, Temperature field, Thermal stress, Three-dimensional finite element relocating mesh method

Xiao-fei Zhang; Shou-yi Li; Yan-long Li; Yao Ge; Hui Li

2011-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "rectangular precast concrete" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Uplift Pressures in Cracks in Concrete Gravity Dams--An Experimental Study: Volume 8  

Science Conference Proceedings (OSTI)

Uplift pressure distribution in cracks in concrete dams is affected by a combination of several factors, such as crack properties, drain dimensions, and the type of flow in the crack. This study shows that most uplift pressure distributions can be controlled using a vertical drain system with diameters from two to four inches and spacing of about ten feet.

1992-12-20T23:59:59.000Z

362

Determining the Impact of Concrete Roadways on Gamma Ray Background Readings for Radiation Portal Monitoring Systems  

E-Print Network (OSTI)

The dissolution of the Soviet Union coupled with the growing sophistication of international terror organizations has brought about a desire to ensure that a sound infrastructure exists to interdict smuggled nuclear material prior to leaving its country of origin. To combat the threat of nuclear trafficking, radiation portal monitors (RPMs) are deployed around the world to intercept illicit material while in transit by passively detecting gamma and neutron radiation. Portal monitors in some locations have reported abnormally high gamma background count rates. The higher background data has been attributed, in part, to the concrete surrounding the portal monitors. Higher background can ultimately lead to more material passing through the RPMs undetected. This work is focused on understanding the influence of the concrete surrounding the monitors on the total gamma ray background for the system. This research employed a combination of destructive and nondestructive analytical techniques with computer simulations to form a model that may be adapted to any RPM configuration. Six samples were taken from three different composition concrete slabs. The natural radiologcal background of these samples was determined using a high-purity germanium (HPGe) detector in conjunction with the Canberra In-Situ Object Counting System (ISOCS) and Genie 2000 software packages. The composition of each sample was determined using thermal and fast neutron activation analysis (NAA) techniques. The results from these experiments were incorporated into a Monte Carlo N-Particle (MNCP) photon transport simulation to determine the expected gamma ray count rate in the RPM due to the concrete. The results indicate that a quantitative estimate may be possible if the experimental conditions are optimized to eliminate sources of uncertainty. Comparisons of actual and simulated count rate data for 137Cs check sources showed that the model was accurate to within 15%. A comparison of estimated and simulated count rates in one concrete slab showed that the model was accurate to within 4%. Subsequent sensitivity analysis showed that if the elemental concentrations are well known, the carbon and hydrogen content could be easily estimated. Another sensitivity analysis revealed that the small fluctuations in density have a minimal impact on the gamma count rate. The research described by this thesis provides a method by which RPM end users may quantitatively estimate the expected gamma background from concrete foundations beneath the systems. This allows customers to adjust alarm thresholds to compensate for the elevated background due to the concrete, thereby increasing the probability of intercepting illicit radiological and nuclear material.

Ryan, Christopher Michael

2011-05-01T23:59:59.000Z

363

Spring 2011 | PCI Journal42 --C--C--C--C--  

E-Print Network (OSTI)

transfer mechanism was intended to increase thermal insulation efficiency, enhance service life Precast, prestressed concrete sandwich wall panels are typically used for building envelopes. Such panels of insulation. The panels can support gravity loads from floors or roofs, resist normal or transverse lateral

364

APFIS Dec 2013 Asia-Pacific Conference on FRP in Structures Melbourne -Australia  

E-Print Network (OSTI)

as bearing wall panels and building envelopes of many structures. The research examine the use of a carbon foam insulation, as the main shear transfer mechanism for precast concrete sandwich panels flow strength of the CGRID/foam insulation material mechanism, including the type of rigid insulating

365

LDRD summary report. Part 1: initiation studies of thin film explosvies used for scabbling concrete. Part 2: investigation of spray techniques for use in explosive scabbling of concrete  

SciTech Connect

We describe a new method for the scabbling of concrete surfaces using a thin layer of explosive material sprayed onto the surfaces. We also developed a new explosive mixture that could be applied with commercial spray painting equipment. The first part of our record describes experiments that studied methods for the initiation of the sprayed explosive. We successfully initiated layers 0.36 mm thick using a commercial EBW detonator, a flying plate detonator, and by pellet impact. The second part of our report describes a survey of spray methods and tests with two commercial spray systems that we believe could be used for developing a robotic spray system.

Benham, R.A.; Bickes, R.W. Jr.; Grubelich, M.C.; Wackerbarth, D.E.; Brock, J.L.

1996-11-01T23:59:59.000Z

366

Experimental results of core-concrete interactions using molten steel with zirconium  

SciTech Connect

Four inductively sustained experiments, QT-D, QT-E, SURC-3, and SURC-3A, were performed in order to investigate the additional effects of zirconium metal oxidation on core debris-concrete interactions using molten stainless steel as the core debris simulant. The QT-D experiment ablated 18 cm of concrete axially during 50 minutes of interaction on limestone-common sand concrete using a 10 kg charge of 304 stainless steel to which 2 kg of zirconium metal was added subsequent to the onset of erosion. The QT-E experiment ablated 10 cm of limestone-common sand concrete axially and 10 cm radially during 35 minutes of sustained interaction using 50 kg of stainless steel and 10 kg of zirconium. The SURC-3 experiment had a 45 kg charge of stainless steel to which 1.1 kg of zirconium was subsequently added. SURC-3 axially eroded 33 cm of limestone concrete during two hours of interaction. The fourth experiment, SURC-3A, eroded 25 cm of limestone concrete axially and 9 cm radially during 90 minutes of sustained interaction. It utilized 40 kg of stainless steel and 2.2 kg of added zirconium as the charge material. All four experiments showed in a large increase in erosion rate, gas production, and aerosol release following the addition of Zr metal to the melt. In the SURC-3 and SURC-3A tests the measured erosion rates increased from 14 cm/hr to 27 cm/hr, gas release increased from 50 slpm to 100 slpm, and aerosol release increased from .02 q/sec to .04 q/sec. The effluent gas was composed of 80% CO, 10% CO{sub 2}, and 2% H{sub 2} before Zr addition and 92% CO, 4% CO{sub 2}, 4% H{sub 2} during the Zr interactions which lasted 10--20 minutes. Addition measurements indicated that the melt pool temperature ranged from 1600{degree}C--1800{degree} and that the aerosols produced were comprised primarily of Te and Fe oxides. 21 refs., 120 figs., 51 tabs.

Copus, E.R.; Blose, R.E.; Brockmann, J.E.; Gomez, R.D.; Lucero, D.A. (Sandia National Labs., Albuquerque, NM (USA))

1990-07-01T23:59:59.000Z

367

Abstract--The inspection of large concrete walls with autonomous systems is still an unsolved problem. One of the  

E-Print Network (OSTI)

is the inspection of concrete walls like bridges, cooling towers or dams. E.g. almost 90% of all motorway bridges structures like cooling towers, tunnels and others, preferably the ones made from reinforced and prestressed

Berns, Karsten

368

Biologically induced concrete deterioration in a wastewater treatment plant assessed by combining microstructural analysis with thermodynamic modeling  

SciTech Connect

In the nitrification basins of wastewater treatment plants, deterioration of the concrete surface can occur due to acid attack caused by a nitrifying biofilm covering the concrete. To identify the mechanism of deterioration, concrete cubes of different composition were suspended in an aerated nitrification basin of a wastewater treatment plant for two years and analyzed afterwards. The microstructural investigation reveals that not only dissolution of hydrates takes place, but that calcite precipitation close to the surface occurs leading to the formation of a dense layer. The degree of deterioration of the different cubes correlates with the CaO content of the different cements used. Cements which contain a high fraction of CaO form more calcite offering a better protection against the acid attack. The presence of slag, which lowers the amount CaO in the cement, leads to a faster deterioration of the concrete than observed for samples produced with pure OPC.

Leemann, A., E-mail: andreas.leemann@empa.c [Empa, Duebendorf (Switzerland); Lothenbach, B.; Hoffmann, C. [Empa, Duebendorf (Switzerland)

2010-08-15T23:59:59.000Z

369

Analytical and Experimental Assessment of Seismic Vulnerability of Beam-Column Joints without Transverse Reinforcement in Concrete Buildings  

E-Print Network (OSTI)

Moehle, J. P. , ?Update to ASCE/SEI 41 Concrete Provisions?,of Structural Engineering, ASCE, V. 122, No. 3, Mar. 1996,the Structural Division, ASCE, V. 97, No. ST 7, July 1971,

Hassan, Wael M.

2011-01-01T23:59:59.000Z

370

OECD 2-D Core Concrete Interaction (CCI) tests : CCI-2 test plan, Rev. 0 January 31, 2004.  

Science Conference Proceedings (OSTI)

The Melt Attack and Coolability Experiments (MACE) program addressed the issue of the ability of water to cool and thermally stabilize a molten core-concrete interaction when the reactants are flooded from above. These tests provided data regarding the nature of corium interactions with concrete, the heat transfer rates from the melt to the overlying water pool, and the role of noncondensable gases in the mixing processes that contribute to melt quenching. As a follow-on program to MACE, The Melt Coolability and Concrete Interaction Experiments (MCCI) project is conducting reactor material experiments and associated analysis to achieve the following objectives: (1) resolve the ex-vessel debris coolability issue through a program that focuses on providing both confirmatory evidence and test data for the coolability mechanisms identified in MACE integral effects tests, and (2) address remaining uncertainties related to long-term two-dimensional molten core-concrete interactions under both wet and dry cavity conditions. Achievement of these two program objectives will demonstrate the efficacy of severe accident management guidelines for existing plants, and provide the technical basis for better containment designs for future plants. In terms of satisfying these objectives, the Management Board (MB) approved the conduct of two long-term 2-D Core-Concrete Interaction (CCI) experiments designed to provide information in several areas, including: (i) lateral vs. axial power split during dry core-concrete interaction, (ii) integral debris coolability data following late phase flooding, and (iii) data regarding the nature and extent of the cooling transient following breach of the crust formed at the melt-water interface. The first of these two tests, CCI-1, was conducted on December 19, 2003. This test investigated the interaction of a fully oxidized 400 kg PWR core melt, initially containing 8 wt % calcined siliceous concrete, with a specially designed two-dimensional siliceous concrete test section with an initial cross-sectional area of 50 cm x 50 cm. The second of these two planned tests, CCI-2, will be conducted with a nearly identical test facility and experiment boundary conditions, but with a Limestone/Common Sand (LCS) concrete test section to investigate the effect of concrete type on the two-dimensional core-concrete interaction and debris cooling behavior. The objective of this report is to provide the overall test plan for CCI-2 to enable pretest calculations to be carried out. The report begins by providing a summary description of the CCI-2 test apparatus, followed by a description of the planned test operating procedure. Overall specifications for CCI-2 are provided in Table 1-1.

Farmer, M. T.; Kilsdonk, D. J.; Lomperski, S.; Aeschlimann, R. W.; Basu, S. (Nuclear Engineering Division)

2011-05-23T23:59:59.000Z

371

Patterns of gravity induced aggregate migration during casting of fluid concretes  

SciTech Connect

In this paper, aggregate migration patterns during fluid concrete castings are studied through experiments, dimensionless approach and numerical modeling. The experimental results obtained on two beams show that gravity induced migration is primarily affecting the coarsest aggregates resulting in a decrease of coarse aggregates volume fraction with the horizontal distance from the pouring point and in a puzzling vertical multi-layer structure. The origin of this multi layer structure is discussed and analyzed with the help of numerical simulations of free surface flow. Our results suggest that it finds its origin in the non Newtonian nature of fresh concrete and that increasing casting rate shall decrease the magnitude of gravity induced particle migration.

Spangenberg, J. [Department of Mechanical Engineering, Technical University of Denmark (DTU) (Denmark)] [Department of Mechanical Engineering, Technical University of Denmark (DTU) (Denmark); Roussel, N., E-mail: Nicolas.roussel@lcpc.fr [Universite Paris Est, Laboratoire Central des Ponts et Chaussees (LCPC) (France); Hattel, J.H. [Department of Mechanical Engineering, Technical University of Denmark (DTU) (Denmark)] [Department of Mechanical Engineering, Technical University of Denmark (DTU) (Denmark); Sarmiento, E.V.; Zirgulis, G. [Department of Structural Engineering, Norwegian University of Science and Technology (NTNU) (Norway)] [Department of Structural Engineering, Norwegian University of Science and Technology (NTNU) (Norway); Geiker, M.R. [Department of Structural Engineering, Norwegian University of Science and Technology (NTNU) (Norway) [Department of Structural Engineering, Norwegian University of Science and Technology (NTNU) (Norway); Department of Civil Engineering, Technical University of Denmark (DTU) (Denmark)

2012-12-15T23:59:59.000Z

372

DETERMINING THE EFFECTS OF RADIATION ON AGING CONCRETE STRUCTURES OF NUCLEAR REACTORS  

SciTech Connect

The U.S. Department of Energy Office of Environmental Management (DOE-EM) is responsible for the Decontamination and Decommissioning (D&D) of nuclear facilities throughout the DOE Complex. Some of these facilities will be completely dismantled, while others will be partially dismantled and the remaining structure will be stabilized with cementitious fill materials. The latter is a process known as In-Situ Decommissioning (ISD). The ISD decision process requires a detailed understanding of the existing facility conditions, and operational history. System information and material properties are need for aged nuclear facilities. This literature review investigated the properties of aged concrete structures affected by radiation. In particular, this review addresses the Savannah River Site (SRS) isotope production nuclear reactors. The concrete in the reactors at SRS was not seriously damaged by the levels of radiation exposure. Loss of composite compressive strength was the most common effect of radiation induced damage documented at nuclear power plants.

Serrato, M.

2010-01-29T23:59:59.000Z

373

Solar process designs being readied in 4 industries. [Canning, textiles, concrete, and laundry  

SciTech Connect

As the Oct. 31 deadline for an initial design review approaches, the four participants in the Energy Research and Development Administration's (ERDA) industrial process hot water program are putting the final touches to plans for solar systems that will supplement conventional energy sources in the textile, food processing, concrete block and cleaning industries. Participating in the project are AAI Corp., Baltimore, which designed a solar hot water system for the concrete block curing operation of York Building Products Co., Harrisburg, Pa.; Acurex Corp., Mountain View, Calif., which designed a solar hot water system for a can washing line at the Campbell Soup Co. plant in Sacramento, Calif.; General Electric Co., Philadelphia, which designed a solar hot water system for Riegel Textile Corp., La France, S.C.; and Jacobs Engineering Co., Pasadena, Calif., which designed a solar hot water and steam system for commercial laundry use at American Linen Supply in El Centro., Calif. (MCW)

Edwards, P.L.

1976-10-11T23:59:59.000Z

374

Development of high integrity, maximum durability concrete structures for LLW disposal facilities  

SciTech Connect

A number of disposal facilities for Low-Level Radioactive Wastes have been planned for the Savannah River Site. Design has been completed for disposal vaults for several waste classifications and construction is nearly complete or well underway on some facilities. Specific design criteria varies somewhat for each waste classification. All disposal units have been designed as below-grade concrete vaults, although the majority will be above ground for many years before being encapsulated with earth at final closure. Some classes of vaults have a minimum required service life of 100 years. All vaults utilize a unique blend of cement, blast furnace slag and pozzolan. The design synthesizes the properties of the concrete mix with carefully planned design details and construction methodologies to (1) eliminate uncontrolled cracking; (2) minimize leakage potential; and (3) maximize durability. The first of these vaults will become operational in 1992. 9 refs.

Taylor, W.P. [Main (Charles T.), Inc., Charlotte, NC (United States)

1992-05-01T23:59:59.000Z

375

Development of high integrity, maximum durability concrete structures for LLW disposal facilities  

SciTech Connect

A number of disposal facilities for Low-Level Radioactive Wastes have been planned for the Savannah River Site. Design has been completed for disposal vaults for several waste classifications and construction is nearly complete or well underway on some facilities. Specific design criteria varies somewhat for each waste classification. All disposal units have been designed as below-grade concrete vaults, although the majority will be above ground for many years before being encapsulated with earth at final closure. Some classes of vaults have a minimum required service life of 100 years. All vaults utilize a unique blend of cement, blast furnace slag and pozzolan. The design synthesizes the properties of the concrete mix with carefully planned design details and construction methodologies to (1) eliminate uncontrolled cracking; (2) minimize leakage potential; and (3) maximize durability. The first of these vaults will become operational in 1992. 9 refs.

Taylor, W.P. (Main (Charles T.), Inc., Charlotte, NC (United States))

1992-01-01T23:59:59.000Z

376

Economic analysis for utilization of geothermal energy by North Dakota Concrete Products Co.  

SciTech Connect

North Dakota Concrete Products Company uses a steam curing process that accelerates the concrete curing so that 28-day strength is obtained within 24 hours. The cost of energy required to accomplish this is significant, amounting to approximately $80,000 in 1980. The present boilers are oil fired. Recently, fuel oil prices have increased substantially. Further, supply shortages in the past have threatened plant production. The purpose of this study was to evaluate the economic feasibility of using deep formation warm water as an alternative energy source. A water-to-water heat pump system to replace the existing boiler system was investigated. TPI, Inc. economic and engineering findings for this particular potential geothermal application are disclosed. The operating cost savings of the geothermal system over the operating costs of the existing oilfired system would be insufficient to provide an acceptable rate of return on the investment at todays cost of money.

Zink, L.L.

1982-02-01T23:59:59.000Z

377

Improving both bond strength and corrosion resistance of steel rebar in concrete by water immersion or sand blasting of rebar  

Science Conference Proceedings (OSTI)

Water immersion (2 days) and sand blasting were similarly effective for treating steel rebars for the purpose of improvement steel-concrete bond strength and corrosion resistance of steel in concrete. The increase in bond strength is due to surface roughening in the case of sand blasting and the presence of a surface layer in the case of water immersion. The increase in corrosion resistance is due to the surface uniformity rendered by either treatment.

Hou, J.; Fu, X.; Chung, D.D.L. [State Univ. of New York, Buffalo, NY (United States). Composite Materials Research Lab.

1997-05-01T23:59:59.000Z

378

Early-age concrete temperature and moisture relative to curing effectiveness and projected effects on selected aspects of slab behavior  

E-Print Network (OSTI)

Concrete curing has long been realized to be important to produce durable concrete. Curing compound is widely used to cure concrete in the field. The current curing membrane evaluation method ASTM C 156, however, is incapable of distinguishing the curing compound quality and guiding the curing practice in the field. A new laboratory curing membrane evaluation protocol is developed in this study. It has the ability to rank the quality of curing compound and guide curing practice in the field according to the field ambient weather conditions and the type of curing compound. A series of field tests were conducted to investigate the key factors that affect the curing effectiveness in the field conditions. A finite element program, temperature and moisture analysis for curing concrete (TMAC2), is updated to solve the coupled and nonlinear heat transfer and moisture transport problems in early-age concrete. Moisture capacity is induced into the TMAC2, which makes it unique to characterize the self-desiccation. A full scale concrete pavement test study was conducted at the FAA National Airport Pavement Test Facility (NAPTF) near Atlantic City, New Jersey. In this study, the material properties, i.e. thermal conductivity and moisture diffusivity, were backcalculated from field data. Thereafter, backcalculated material properties were used to forward-calculate the temperature and moisture histories of all other sections. High order shear deformable theory is used to model the concrete slab curling and warping behavior because of highly nonlinear temperature and moisture gradients. The maximum shear strain is obtained a couple of inches below the concrete slab. This might account for the occurrence of delamination.

Ye, Dan

2007-08-01T23:59:59.000Z

379

PROJECTED IMPACT OF SULFATE ATTACK ON THE LONG-TERM PERFORMANCE OF A CONCRETE REPOSITORY  

Science Conference Proceedings (OSTI)

Saltstone is a cementitious waste form made by mixing salt solution originating from liquid waste storage tanks at the DOE Savannah River Site with a dry mix containing blast furnace slag, fly ash, and cement or lime. The wet mix is poured into a concrete repository for on-site disposal. Solidified Saltstone is a dense, alkaline, reducing, micro-porous, monolithic, cementitious matrix, containing a solution of salts within its pore structure. Sodium sulfate concentrations in the pore fluid are around 0.15 mol/L, and external sulfate attack on concrete barriers is expected to occur over time. To predict the long-term performance of concrete repositories, the STADIUM{reg_sign} code was used to simulate the reactive transport processes leading to formation of ettringite, an expansive mineral phase often associated with spalling or cracking. STADIUM{reg_sign} is a multi-ionic transport model based on a split operator approach that separates ionic movement and chemical reactions. Ionic transport is described by the extended Nernst-Planck equation for unsaturated media, and accounts for electrical coupling between ionic species, chemical activity, transport due to water content gradient, and temperature effects. STADIUM{reg_sign} does not predict whether physical damage will occur, or the impact on transport properties should fracturing occur. Thus the presence of ettringite was assumed to coincide with physical damage for the purpose of estimating effective transport properties. Effective properties for concrete barriers were estimated assuming complete hydraulic failure behind the ettringite front and unaltered properties ahead of the front. The ettringite front advances at a rate dependent on the diffusion coefficient assumed for the failed zone. A sensitivity study indicates a service life ranging from thousands to tens of thousands of years, depending on the barrier thickness and sulfate exposure conditions among other factors.

Flach, G.

2009-12-11T23:59:59.000Z

380

Development and Performance Evaluation of High Temperature Concrete for Thermal Energy Storage for Solar Power Generation  

DOE Green Energy (OSTI)

Two different storage methods are investigated. In the first one heat is transported using molten slat through a stainless steel tube and heat is transported into concrete block through diffusion. The cost of the system is higher than the targeted DOE goal of $15/kWhthermal The increase in cost of the system is due to stainless steel tube to transfer the heat from molten salt to the concrete blocks.The other method is a one-tank thermocline system in which both the hot and cold fluid occupy the same tank resulting in reduced storage tank volume. In this model, heated molten salt enters the top of the tank which contains a packed bed of quartzite rock and silica sand as the thermal energy storage (TES) medium. The single-tank storage system uses about half the salt that is required by the two-tank system for a required storage capacity. This amounts to a significant reduction in the cost of the storage system. The single tank alternative has also been proven to be cheaper than the option which uses large concrete modules with embedded heat exchangers. Using computer models optimum dimensions are determined to have an round trip efficiency of 84%. Additionally, the cost of the structured concrete thermocline configuration provides the TES capacity cost of $33.80$/kWhthermal compared with $30.04/kWhthermal for a packed-bed thermocline (PBTC) configuration and $46.11/kWhthermal for a two-tank liquid configuration.

R. Panneer Selvam, Micah Hale and Matt strasser

2013-03-31T23:59:59.000Z

Note: This page contains sample records for the topic "rectangular precast concrete" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
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381

Program on Technology Innovation: Nondestructive Evaluation Inspection of Concrete Structures Subjected to Corrosion  

Science Conference Proceedings (OSTI)

Corrosion of embedded steel elements (reinforcement, liner, and a pretensioning or post-tensioning device) is a major cause of concrete structure dysfunction, resulting in large maintenance and repair costs worldwide. This report, based on a literature survey and laboratory tests conducted at the Electric Power Research Institute (EPRI), provides a review of the nondestructive techniques (essentially electrochemicalthat is, half-cell potential [HCP], resistivity, and polarization-resistance techniques), ...

2012-05-31T23:59:59.000Z

382

Program on Technology Innovation: Three-Dimensional Imaging of Corroded Reinforcement in Concrete  

Science Conference Proceedings (OSTI)

The assessment of corrosion of embedded steel in concrete structures is generally performed by electrochemical methods (half-cell potential and linear polarization) that are not fully nondestructive because the device requires connection to the steel. For practical application on large-scale structures, such as containment buildings and cooling towers, the development of a truly nondestructive technique for the detection of corrosion activity is desirable. This experimental study sponsored by the ...

2013-07-03T23:59:59.000Z

383

Computer Based Training: Engineering Technical Training Modules - Concrete Anchors v1.0  

Science Conference Proceedings (OSTI)

Concrete Anchors, ETTM, is a computer based training module that allows users to access training when desired and review it at their own pace. It provides graphics and limited interactive features to enhance learning. This module provides information about the basics of structural mechanics and the fundamentals of the dynamic response of structural systems. This computer-based training (CBT) module is intended for use by new engineers as well as engineers changing jobs where basic knowledge of this subje...

2010-01-26T23:59:59.000Z

384

Steep-Slope Assembly Testing of Clay and Concrete Tile With and Without Cool Pigmented Colors  

Science Conference Proceedings (OSTI)

Cool color pigments and sub-tile venting of clay and concrete tile roofs significantly impact the heat flow crossing the roof deck of a steep-slope roof. Field measures for the tile roofs revealed a 70% drop in the peak heat flow crossing the deck as compared to a direct-nailed asphalt shingle roof. The Tile Roofing Institute (TRI) and its affiliate members are keenly interested in documenting the magnitude of the drop for obtaining solar reflectance credits with state and federal "cool roof" building efficiency standards. Tile roofs are direct-nailed or are attached to a deck with batten or batten and counter-batten construction. S-Misson clay and concrete tile roofs, a medium-profile concrete tile roof, and a flat slate tile roof were installed on fully nstrumented attic test assemblies. Temperature measures of the roof, deck, attic, and ceiling, heat flows, solar reflectance, thermal emittance, and the ambient weather were recorded for each of the tile roofs and also on an adjacent attic cavity covered with a conventional pigmented and directnailed asphalt shingle roof. ORNL measured the tile's underside temperature and the bulk air temperature and heat flows just underneath the tile for batten and counter-batten tile systems and compared the results to the conventional asphalt shingle.

Miller, William A [ORNL

2005-11-01T23:59:59.000Z

385

{sup 152}Eu depths profiles granite and concrete cores exposed to the Hiroshima atomic bomb  

SciTech Connect

Two granite and two concrete core samples were obtained within 500 m from the hypocenter of the Hiroshima atomic bomb, and the depth profile of {sup 152}Eu was measured to evaluate the incident neutron spectrum. The granite cores were obtained from a pillar of the Motoyasu Bridge located 101 m from the hypocenter and from a granite rock in the Shirakami Shrine (379 m); the concrete cores were obtained from a gate in the Gokoku Shrine (398 m) and from top of the Hiroshima bank (250 m). The profiles of the specific activities of the cores were measured to a depth of 40 cm from the surface using low background germanium (Ge) spectrometers. According to the measured depth profiles, relaxation lengths of incident neutrons were derived as 13.6 cm for Motoyasu Bridge pillar (granite), 12.2 cm for Shirakami Shrine core (granite), and 9.6 cm for concrete cores of Gokoku Shrine and Hiroshima Bank. In addition, a comparison of the granite cores in Hiroshima showed good agreement with Nagasaki data. Present results indicates that the depth profile of {sup 152}Eu reflects incident neutrons not so high but in the epithermal region. 19 refs., 7 figs., 8 tabs.

Shizuma, Kiyoshi; Iwatani, Kazuo [Hiroshima Univ. (Japan); Oka, Takamitsu [Kure Univ. (Japan)] [and others

1997-06-01T23:59:59.000Z

386

ASSESSMENT OF RADIONUCLIDE RELEASE FROM CONTAMINATED CONCRETE AT THE YANKEE NUCLEAR POWER STATION.  

Science Conference Proceedings (OSTI)

Yankee Atomic Energy Company (YAEC) is considering allowing portions of existing structures at the Yankee Nuclear Power Station (YNPS) to remain on site at the time of license termination. Accordingly, release of residual radioactive contaminants (i.e., H-3, C-14, Co-60, Ni-63, Sr-90, and Cs-137) from remaining subsurface concrete structures (Darman, 2004) and dose due to that release must be evaluated. Analyses were performed using DUST-MS to assess the rate of release for each radionuclide from the concrete, based upon an assumed concentration of 1 pCi/g and a concrete density of 2.5 g/cm{sup 3}. Using the same assumptions that were applied to the soil DCGL calculation (and where appropriate, the same input parameters), RESRAD was used to calculate the dose from water pathways. Values for selected RESRAD input parameters were chosen to match the release rate calculated by DUST-MS. The results indicated that Cs-137 yielded the highest dose.

SULLIVAN, T.

2004-03-01T23:59:59.000Z

387

Thermal and environmental effects on fiber-reinforced polymer reinforcing bars and reinforced concrete elements  

E-Print Network (OSTI)

Corrosion of steel reinforcement in bridge decks results in high repair costs, unwanted traffic disruption, and unsafe structures. To help alleviate this problem, non-metallic fiber-reinforced polymer (FRP) bars are being studied as an alternate type of reinforcement in bridge decks. In order to determine the suitability of the use of FRP bars, a number of tests have been performed on FRP bars to evaluate their long-term performance. These tests include uniaxial tension tests under a variety of environmental conditions and thermal expansion of the bars embedded in concrete. In an effort to characterize the FRP bars and to gain insight into their long-term performance, batteries of tests have been carried out. Samples from three different manufacturers were exposed under different environmental conditions and tested in uniaxial tension. For one of the bar types, the strength increased, while the other two bar types lost strength. In all cases, the modulus of the bars increased with exposure time. In addition, FRP reinforced concrete specimens were evaluated for thermal expansion. The results indicate that thermal cracking of the concrete by FRP bar expansion is not a significant problem.

Schaefer, Benjamin Carl

2002-01-01T23:59:59.000Z

388

Encapsulation of lead from hazardous CRT glass wastes using biopolymer cross-linked concrete systems  

Science Conference Proceedings (OSTI)

Discarded computer monitors and television sets are identified as hazardous materials due to the high content of lead in their cathode ray tubes (CRTs). Over 98% of lead is found in CRT glass. More than 75% of obsolete electronics including TV and CRT monitors are in storage because appropriate e-waste management and remediation technologies are insufficient. Already an e-waste tsunami is starting to roll across the US and the whole world. Thus, a new technology was developed as an alternative to current disposal methods; this method uses a concrete composite crosslinked with minute amounts of biopolymers and a crosslinking agent. Commercially available microbial biopolymers of xanthan gum and guar gum were used to encapsulate CRT wastes, reducing Pb leachability as measured by standard USEPA methods. In this investigation, the synergistic effect of the crosslinking reaction was observed through blending two different biopolymers or adding a crosslinking agent in biopolymer solution. This CRT-biopolymer-concrete (CBC) composite showed higher compressive strength than the standard concrete and a considerable decrease in lead leachability.

Kim, Daeik; Quinlan, Michael [Sonny Astani Department of Civil and Environmental Engineering, Viterbi School of Engineering, University of Southern California, KAP 210, 3620 South Vermont Avenue, Los Angeles, CA 90089 (United States); Yen, Teh Fu [Sonny Astani Department of Civil and Environmental Engineering, Viterbi School of Engineering, University of Southern California, KAP 210, 3620 South Vermont Avenue, Los Angeles, CA 90089 (United States)], E-mail: tfyen@usc.edu

2009-01-15T23:59:59.000Z

389

Experimental assessment of air permeability in a concrete shear wall subjected to simulated seismic loading  

Science Conference Proceedings (OSTI)

A safety concern for the proposed Special Nuclear Materials Laboratory (SNML) facility at the Los Alamos National Laboratory was air leakage from the facility if it were to experience a design basis earthquake event. To address this concern, a study was initiated to estimate air leakage, driven by wind-generated pressure gradients, from a seismically damaged concrete structure. This report describes a prototype experiment developed and performed to measure the air permeability in a reinforced concrete shear wall, both before and after simulated seismic loading. A shear wall test structure was fabricated with standard 4000-psi concrete mix. Static load-cycle testing was used to simulate earthquake loading. Permeability measurements were made by pressurizing one side of the shear wall above atmospheric conditions and recording the transient pressure decay. As long as the structure exhibited linear load displacement response, no variation in the air permeability was detected. However, experimental results indicate that the air permeability in the shear wall increased by a factor of 40 after the wall had been damaged (cracked). 17 figs., 8 tabs.

Girrens, S.P.; Farrar, C.R.

1991-07-01T23:59:59.000Z

390

Behavior of Concrete Panels Reinforced with Synthetic Fibers, Mild Steel, and GFRP Composites Subjected to Blasts  

SciTech Connect

The paper presents experimental data generated for calibrating finite element models to predict the performance of reinforced concrete panels with a wide range of construction details under blast loading. The specimens were 1.2 m square panels constructed using Normal Weight Concrete (NWC) or Fiber Reinforced Concrete (FRC). FRC consisted of macro-synthetic fibers dispersed in NWC. Five types of panels were tested: NWC panels with steel bars; FRC panels without additional reinforcement; FRC panels with steel bars; NWC panels with glass fiber reinforced polymer (GFRP) bars; and NWC panels reinforced with steel bars and external GFRP laminates on both faces. Each panel type was constructed with three thicknesses: 152 mm, 254 mm, and 356 mm. FRC panels with steel bars had the best performance for new construction. NWC panels reinforced with steel bars and external GFRP laminates on both faces had the best performance for strengthening or rehabilitation of existing structures. The performance of NWC panels with GFRP bars was strongly influenced by the bar spacing. The behavior of the panels is classified in terms of damage using immediate occupancy, life safety, and near collapse performance levels. Preliminary dynamic simulations are compared to the experimental results.

C. P. Pantelides; T. T. Garfield; W. D. Richins; T. K. Larson; J. E. Blakeley

2012-03-01T23:59:59.000Z

391

Diffusion and Leaching Behavior of Radionuclides in Category 3 Waste Encasement Concrete and Soil Fill Material Summary Report  

SciTech Connect

One of the methods being considered for safely disposing of Category 3 low-level radioactive wastes is to encase the waste in concrete. Such concrete encasement would contain and isolate the waste packages from the hydrologic environment and would act as an intrusion barrier. The current plan for waste isolation consists of stacking low-level waste packages on a trench floor, surrounding the stacks with reinforced steel, and encasing these packages in concrete. These concrete-encased waste stacks are expected to vary in size with maximum dimensions of 6.4 m long, 2.7 m wide, and 4 m high. The waste stacks are expected to have a surrounding minimum thickness of 15 cm of concrete encasement. These concrete-encased waste packages are expected to withstand environmental exposure (solar radiation, temperature variations, and precipitation) until an interim soil cover or permanent closure cover is installed, and to remain largely intact thereafter. Any failure of concrete encasement may result in water intrusion and consequent mobilization of radionuclides from the waste packages. The mobilized radionuclides may escape from the encased concrete by mass flow and/or diffusion and move into the surrounding subsurface environment. Therefore, it is necessary to assess the performance of the concrete encasement structure and the ability of the surrounding soil to retard radionuclide migration. The retardation factors for radionuclides contained in the waste packages can be determined from measurements of diffusion coefficients for these contaminants through concrete and fill material. Some of the mobilization scenarios include (1) potential leaching of waste form before permanent closure cover is installed; (2) after the cover installation, long-term diffusion of radionuclides from concrete waste form into surrounding fill material; (3) diffusion of radionuclides from contaminated soils into adjoining concrete encasement and clean fill material. Additionally, the rate of diffusion of radionuclides may be affected by the formation of structural cracks in concrete, the carbonation of the buried waste form, and any potential effect of metallic iron (in the form of rebars) on the mobility of radionuclides. The radionuclides iodine-129 ({sup 129}I), technetium-99 ({sup 99}Tc), and uranium-238 ({sup 238}U) are identified as long-term dose contributors in Category 3 waste (Mann et al. 2001; Wood et al. 1995). Because of their anionic nature in aqueous solutions, {sup 129}I, {sup 99}Tc, and carbonate-complexed {sup 238}U may readily leach into the subsurface environment (Serne et al. 1989, 1992a, b, 1993, and 1995). The leachability and/or diffusion of radionuclide species must be measured to assess the long-term performance of waste grouts when contacted with vadose-zone pore water or groundwater. Although significant research has been conducted on the design and performance of cementitious waste forms, the current protocol conducted to assess radionuclide stability within these waste forms has been limited to the Toxicity Characteristic Leaching Procedure, Method 1311 Federal Registry (EPA 1992) and ANSI/ANS-16.1 leach test (ANSI 1986). These tests evaluate the performance under water-saturated conditions and do not evaluate the performance of cementitious waste forms within the context of waste repositories which are located within water-deficient vadose zones. Moreover, these tests assess only the diffusion of radionuclides from concrete waste forms and neglect evaluating the mechanisms of retention, stability of the waste form, and formation of secondary phases during weathering, which may serve as long-term secondary hosts for immobilization of radionuclides. The results of recent investigations conducted under arid and semi-arid conditions (Al-Khayat et al. 2002; Garrabrants et al. 2002; Garrabrants and Kosson 2003; Garrabrants et al. 2004; Gervais et al. 2004; Sanchez et al. 2002; Sanchez et al. 2003) provide valuable information suggesting structural and chemical changes to concrete waste forms which may affect contaminant containm

Mattigod, Shas V.; Wellman, Dawn M.; Bovaird, Chase C.; Parker, Kent E.; Clayton, Libby N.; Powers, Laura; Recknagle, Kurtis P.; Wood, Marcus I.

2011-08-31T23:59:59.000Z

392

DAMAGE TO CONVENTIONAL AND SPECIAL TYPES OF RESIDENCES EXPOSED TO NUCLEAR EFFECTS  

SciTech Connect

Ten residential structures of wood, brick, lightweight reinforced concrete block, and lightweight precast concrete slabs were exposed in pairs to the effects of a nuclear device of approximately 30 kt yield, detonated atop a 500-ft tower. The houses represented various structural types, and two houses of each type were tested. One house was located at an anticipated overpressure at which collapse or major damage might be expected and the other was located at an anticipated overpressure at which damage without collapse might be expected. The one-story reinforced lightweight concrete block house and the one-story precast lightweight concrete house suffered only minor structural damage. Photographs are included of the houses both before and after damage. Motion pictures were made during the event and were analyzed for information on thermal and blast effects. Recommendations are included for strengthening the structures within the limits of practical economy and so providing increased protection to dwelling structures. (C.H.)

Randall, P.A.

1961-03-01T23:59:59.000Z

393

Addressing Facility Needs for Concrete Assessment Using Ultrasonic Testing: Mid-year Report  

SciTech Connect

The UFD Gap Analysis to Support Extended Storage of Used Nuclear Fuel (June 30, 2011) emphasizes the need for the development of monitoring techniques and technologies for dry storage cask materials. A high priority is given to the development of 'systems for early detection of confinement boundary degradation.' This requires both new techniques for monitoring and inspection, as well as new measurable parameters to quantify mechanical degradation. The use of Nonlinear Elastic Wave Spectroscopy (NEWS) has been shown to provide sensitive parameters correlating to mechanical degradation in a wide variety of materials. Herein we report upon recent research performed to address the high priority of concrete degradation using a selection of these techniques and compare to a ASTM standard ultrasonic technique. Also reported are the near term plans to continue this research in the remaining FY and into the coming years. This research was conducted at Los Alamos National Laboratory (LANL) in the Acoustics Lab of the Geophysics group in the Earth and Environmental Sciences division, and in collaboration with the Laboratory for Nondestructive Evaluation at the University of the Mediterranean (Aix en Provence, France) and the Electrical Power Research Institute (EPRI). The objective of this research project was to determine the feasibility of using an NDE technique based on non-linear ultrasound for determining the depth and degree of microcracking in the near surface of concrete and to assess the degree of sensitivity of such technique. This objective is reached by the means of combining linear and nonlinear measurements, associated with numerical simulation. We first study the global effect of thermal damage on concrete's linear and nonlinear properties by resonance inspection techniques. We show that standard pulse wave speed techniques are not relevant to extract mechanical properties of concrete. The high sensitivity of measured nonlinearity is shown and serves as a validation tool for the rest of the study, i.e., probing the material nonlinearity at various depths through the use of Time Reversal Elastic Nonlinearity Diagnostic (TREND). The basic idea of probing the material nonlinearity at various depths by changing the frequency is validated by exhibiting a similar trend as nonlinear resonance measurements. We address at the end of this report, the potentialities of applying these procedures to real concrete structures.

Ulrich, Timothy J. II [Los Alamos National Laboratory; Payan, Cedric [EES-17: GEOPHYSICS, Visitor; Roberts, Peter M. [Los Alamos National Laboratory

2012-03-28T23:59:59.000Z

394

TESTING AND ANALYSIS OF CAP CONCRETE STRESS AND STRAIN DUE TO SHRINKAGE, CREEP, AND EXPANSION FINAL REPORT  

Science Conference Proceedings (OSTI)

In-situ decommissioning of Reactors P- and R- at the Savannah River Site will require filling the reactor vessels with a special concrete based on materials such as magnesium phosphate, calcium aluminate or silica fume. Then the reactor vessels will be overlain with an 8 ft. thick layer of Ordinary Portland Cement (OPC) steel reinforced concrete, called the 'Cap Concrete'. The integrity of this protective layer must be assured to last for a sufficiently long period of time to avoid ingress of water into the reactor vessel and possible movement of radioactive contamination into the environment. During drying of this Cap Concrete however, shrinkage strains are set up in the concrete as a result of diffusion and evaporation of water from the top surface. This shrinkage varies with depth in the poured slab due to a non-uniform moisture distribution. This differential shrinkage results in restraint of the upper layers with larger shrinkage by lower layers with lesser displacements. Tensile stresses can develop at the surface from the strain gradients in the bulk slab, which can lead to surface cracking. Further, a mechanism called creep occurs during the curing period or early age produces strains under the action of restraining forces. To investigate the potential for surface cracking, an experimental and analytical program was started under TTQAP SRNL-RP-2009-01184. Slab sections made of Cap Concrete mixture were instrumented with embedded strain gages and relative humidity sensors and tested under controlled environmental conditions of 23 C and relative humidities (RH) of 40% and 80% over a period of 50 days. Calculation methods were also developed for predictions of stress development in the full-scale concrete placement over the reactor vessels. These methods were evaluated by simulating conditions for the test specimens and the calculation results compared to the experimental data. A closely similar test with strain gages was performed by Kim and Lee for a concrete mixture that did not employ humidity sensors and the admixtures used in this program. Yuan and Wan tried to predict the shrinkage strains and stresses in the Kim and Lee experiment, but did not include a creep analysis. Grasley and Lange conducted full restraint load tests on a concrete prism instrumented with humidity sensors over a 7 day curing period. The hypothetical case of full-scale placement of the Cap Concrete was also analyzed using the developed analytical methods. The calculation performed in this report is for scoping purposes only.

Guerrero, H.; Restivo, M.

2011-08-01T23:59:59.000Z

395

Effect of rib spacing on heat transfer and friction in a rotating two-pass rectangular (AR=1:2) channel  

E-Print Network (OSTI)

The research focuses on testing the heat transfer enhancement in a channel for different spacing of the rib turbulators. Those ribs are put on the surface in the two pass rectangular channel with an aspect ratio of AR=1:2. The cross section of the rib is 1.59 x 1.59 mm. Those ribs are put on the leading and trailing walls of the channel with the angle of flow attack to the mainstream of 45?°. The rotating speed is fixed at 550-RPM with the channel orientation at ?²=90?°. Air is used as the coolant through the cooling passage with the coolant-to-wall density ratio ( ρ ρ â?? ) maintained around 0.115 in the first pass and 0.08 in the second pass. The Reynolds numbers are controlled at 5000, 10000, 25000, and 40000. The rib spacing-to-height ratios (P/e) are 3, 5, 7.5, and 10. The heat transfer coefficient and friction factor are measured to determine the effect of the different rib distributions. Stationary cases and rotational cases are examined and compared. The result shows that the highest thermal performance is P/e=5 for the stationary case and P/e=7.5 for the rotating case.

Liu, Yao-Hsien

2005-08-01T23:59:59.000Z

396

Effect of flow topology on the calculation of two-phase frictional multipliers in uniformly heated flow of R-134a in a rectangular duct  

SciTech Connect

The two-phase frictional multipliers for SUVA R-134a flowing in a rectangular duct (with D{sub H} = 4.8 mm) have been measured for three nominal system pressures (0.88, 1.34 and 2.34 MPa) and four nominal mass fluxes (510, 1020 and 1740, 2040 kg/m{sup 2}/s) under uniform heat flux conditions. The data is compared with adiabatic data previously taken at similar flow conditions, as well as with several classical multiplier correlations. The comparisons reveal a strong effect of pressure and mass flux on the flow topology and, by extension, a large effect on the calculation of acceleration and frictional pressure drop components. For this fluid and this geometry, entrainment and fluid separation is enhanced at higher pressures and mass flux such that most of the liquid exists in the test section edges and as dispersed droplets in the core. For these cases, the classical simplified approach to calculate acceleration pressure drop fails to adequately predict the acceleration component and leads to erroneous calculations of frictional pressure drop from the measured total pressure drop. Best estimates of the true acceleration component are given, based on void profiles measured with a gamma densitometer system, comparisons to the adiabatic data, and recasting the data in terms of the total pressure drop multiplier as a function of the Martinelli parameter, X{sub tt}. (author)

Vassallo, Peter; Kevin Cope, W.; Smith, Walter C. [Bechtel Marine Propulsion Corporation, Niskayuna, NY 12309 (United States)

2010-11-15T23:59:59.000Z

397

OECD/MCCI 2-D Core Concrete Interaction (CCI) tests : final report February 28, 2006.  

SciTech Connect

Although extensive research has been conducted over the last several years in the areas of Core-Concrete Interaction (CCI) and debris coolability, two important issues warrant further investigation. The first issue concerns the effectiveness of water in terminating a CCI by flooding the interacting masses from above, thereby quenching the molten core debris and rendering it permanently coolable. This safety issue was investigated in the EPRI-sponsored Melt Attack and Coolability Experiments (MACE) program. The approach was to conduct large scale, integral-type reactor materials experiments with core melt masses ranging up to two metric tons. These experiments provided unique, and for the most part repeatable, indications of heat transfer mechanism(s) that could provide long term debris cooling. However, the results did not demonstrate definitively that a melt would always be completely quenched. This was due to the fact that the crust anchored to the test section sidewalls in every test, which led to melt/crust separation, even at the largest test section lateral span of 1.20 m. This decoupling is not expected for a typical reactor cavity, which has a span of 5-6 m. Even though the crust may mechanically bond to the reactor cavity walls, the weight of the coolant and the crust itself is expected to periodically fracture the crust and restore contact with the melt. Although crust fracturing does not ensure that coolability will be achieved, it nonetheless provides a pathway for water to recontact the underlying melt, thereby allowing other debris cooling mechanisms to proceed. A related task of the current program, which is not addressed in this particular report, is to measure crust strength to check the hypothesis that a corium crust would not be strong enough to sustain melt/crust separation in a plant accident. The second important issue concerns long-term, two-dimensional concrete ablation by a prototypic core oxide melt. As discussed by Foit the existing reactor material database for dry cavity conditions is solely one-dimensional. Although the MACE Scoping Test was carried out with a two-dimensional concrete cavity, the interaction was flooded soon after ablation was initiated to investigate debris coolability. Moreover, due to the scoping nature of this test, the apparatus was minimally instrumented and therefore the results are of limited value from the code validation viewpoint. Aside from the MACE program, the COTELS test series also investigated 2-D CCI under flooded cavity conditions. However, the input power density for these tests was quite high relative to the prototypic case. Finally, the BETA test series provided valuable data on 2-D core concrete interaction under dry cavity conditions, but these tests focused on investigating the interaction of the metallic (steel) phase with concrete. Due to these limitations, there is significant uncertainty in the partition of energy dissipated for the ablation of concrete in the lateral and axial directions under dry cavity conditions for the case of a core oxide melt. Accurate knowledge of this 'power split' is important in the evaluation of the consequences of an ex-vessel severe accident; e.g., lateral erosion can undermine containment structures, while axial erosion can penetrate the basemat, leading to ground contamination and/or possible containment bypass. As a result of this uncertainty, there are still substantial differences among computer codes in the prediction of 2-D cavity erosion behavior under both wet and dry cavity conditions. In light of the above issues, the OECD-sponsored Melt Coolability and Concrete Interaction (MCCI) program was initiated at Argonne National Laboratory. The project conducted reactor materials experiments and associated analysis to achieve the following technical objectives: (1) resolve the ex-vessel debris coolability issue through a program that focused on providing both confirmatory evidence and test data for the coolability mechanisms identified in MACE integral effects tests, and (2) address remaining uncertainties relat

Farmer, M. T.; Lomperski, S.; Kilsdonk, D. J.; Aeschlimann, R. W.; Basu, S. (Nuclear Engineering Division); (NRC)

2011-05-23T23:59:59.000Z

398

General Outline for Conducting Quality Inspections and Tests of Concrete Placement at Nuclear Facilities: Standard and Optimized for Electronic Viewing Versions  

Science Conference Proceedings (OSTI)

This field guide provides a field-deployable resource for utility professionals who are responsible for inspecting and testing concrete placements at nuclear facilities. It addresses development and submittal of concrete mixes, qualification and inspection of batching facilities, qualification of testing agencies and personnel, review of construction procedures, and development of inspection and testing plans. It also provides checklists for pre-placement inspection; concrete conveyance; placement ...

2013-05-30T23:59:59.000Z

399

Properties of salt-saturated concrete and grout after six years in situ at the Waste Isolation Pilot Plant  

SciTech Connect

Samples of concrete and grout were recovered from short boreholes in the repository floor at the Waste Isolation Pilot Plant more than six years after the concrete and grout were placed. Plugs from the Plug Test Matrix of the Plugging and Sealing Program of Sandia National Laboratories were overcored to include a shell of host rock. The cores were analyzed at the Waterways Experiment Station to assess their condition after six years of service, having potentially been exposed to those aspects of their service environment (salt, brine, fracturing, anhydrite, etc.) that could cause deterioration. Measured values of compressive strength and pulse velocity of both the grout and the concrete equaled or exceeded values from tests performed on laboratory-tested samples of the same mixtures at ages of one month to one year after casting. The phase assemblages had changed very little. Materials performed as intended and showed virtually no chemical or physical evidence of deterioration. The lowest values for strength and pulse velocity were measured for samples taken from the Disturbed Rock Zone, indicating the influence of cracking in this zone on the properties of enclosed seal materials. There was evidence of movement of brine in the system. Crystalline phases containing magnesium, potassium, sulfate, and other ions had been deposited on free surfaces in fractures and pilot holes. There was a reaction rim in the anhydrite immediately surrounding each recovered borehole plug, suggesting interaction between grout or concrete and host rock. However, the chemical changes apparent in this reaction rim were not reflected in the chemical composition of the adjacent concrete or grout. The grout and concrete studied here showed no signs of the deterioration found to have occurred in some parts of the concrete liner of the Waste Isolation Pilot Plant waste handling shaft.

Wakeley, L.D.; Harrington, P.T.; Weiss, C.A. Jr. [Army Engineer Waterways Experiment Station, Vicksburg, MS (United States). Structures Lab.

1993-06-01T23:59:59.000Z

400

Buildings Energy Data Book: 1.6 Embodied Energy of Building Assemblies  

Buildings Energy Data Book (EERE)

7 7 Embodied Energy of Floor Structures in the U.S. Floor Structure with Interior Ceiling Finish of Gypsum Board, Latex Paint Embodied Energy CO2 Equivalent (MMBtu/SF) (1) Emissions (lbs/SF) Glulam joist and plank decking 0.04 3.06 Precast Hollowcore 0.05 13.43 Wood I-joist 0.02 2.03 Open-web Steel Joist 0.06 7.94 Open-web Steel Joist with concrete topping 0.07 12.30 Precast Double-T 0.04 11.38 Precast Double-T with concrete topping 0.06 16.45 Steel Joist 0.06 8.82 Steel Joist with plywood decking 0.06 9.28 Suspended Concrete Slab 0.12 29.19 Wood Joist 0.02 1.65 Wood Joist with plywood decking 0.03 2.38 Wood Chord and Steel Web truss 0.05 5.91 Wood Truss 0.03 2.71 Floor Structure without Interior Ceiling Finish Glulam joist and plank decking 0.05 4.32 Precast Hollowcore 0.06 14.68 Wood I-joist 0.04 3.26

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401

A thermal active restrained shrinkage ring test to study the early age concrete behaviour of massive structures  

Science Conference Proceedings (OSTI)

In massive concrete structures, cracking may occur during hardening, especially if autogenous and thermal strains are restrained. The concrete permeability due to this cracking may rise significantly and thus increase leakage (in tank, nuclear containment...) and reduce the durability. The restrained shrinkage ring test is used to study the early age concrete behaviour (delayed strains evolution and cracking). This test shows, at 20 {sup o}C and without drying, for a concrete mix which is representative of a French nuclear power plant containment vessel (w/c ratio equal to 0.57), that the amplitude of autogenous shrinkage (about 40 {mu}m/m for the studied concrete mix) is not high enough to cause cracking. Indeed, in this configuration, thermal shrinkage is not significant, whereas this is a major concern for massive structures. Therefore, an active test has been developed to study cracking due to restrained thermal shrinkage. This test is an evolution of the classical restrained shrinkage ring test. It allows to take into account both autogenous and thermal shrinkages. Its principle is to create the thermal strain effects by increasing the temperature of the brass ring (by a fluid circulation) in order to expand it. With this test, the early age cracking due to restrained shrinkage, the influence of reinforcement and construction joints have been experimentally studied. It shows that, as expected, reinforcement leads to an increase of the number of cracks but a decrease of crack widths. Moreover, cracking occurs preferentially at the construction joint.

Briffaut, M. [LMT/ENS Cachan/CNRS UMR8535/UPMC/PRES UniverSud Paris, Cachan (France); Institut de radioprotection et de surete nucleaire, Fontenay-aux-Roses (France); Benboudjema, F. [LMT/ENS Cachan/CNRS UMR8535/UPMC/PRES UniverSud Paris, Cachan (France); Torrenti, J.M., E-mail: jean-michel.torrenti@lcpc.f [Universite Paris Est, Laboratoire central des ponts et chaussees, Paris (France); Nahas, G. [LMT/ENS Cachan/CNRS UMR8535/UPMC/PRES UniverSud Paris, Cachan (France); Institut de radioprotection et de surete nucleaire, Fontenay-aux-Roses (France)

2011-01-15T23:59:59.000Z

402

Core-concrete interactions with overlying water pools. The WETCOR-1 test  

Science Conference Proceedings (OSTI)

The WETCOR-1 test of simultaneous interactions of a high-temperature melt with water and a limestone/common-sand concrete is described. The test used a 34.1-kg melt of 76.8 w/o Al{sub 2}O{sub 3}, 16.9 w/o CaO, and 4.0 w/o SiO{sub 2} heated by induction using tungsten susceptors. Once quasi-steady attack on concrete by the melt was established, an attempt was made to quench the melt at 1850 K with 295 K water flowing at 57 liters per minute. Net power into the melt at the time of water addition was 0.61 {plus_minus} 0.19 W/cm{sup 3}. The test configuration used in the WETCOR-1 test was designed to delay melt freezing to the walls of the test fixture. This was done to test hypotheses concerning the inherent stability of crust formation when high-temperature melts are exposed to water. No instability in crust formation was observed. The flux of heat through the crust to the water pool maintained over the melt in the test was found to be 0.52 {plus_minus} 0.13 MW/m{sup 2}. Solidified crusts were found to attenuate aerosol emissions during the melt concrete interactions by factors of 1.3 to 3.5. The combination of a solidified crust and a 30-cm deep subcooled water pool was found to attenuate aerosol emissions by factors of 3 to 15.

Blose, R.E. [Ktech Corp., Albuquerque, NM (United States); Powers, D.A.; Copus, E.R.; Brockmann, J.E.; Simpson, R.B.; Lucero, D.A. [Sandia National Labs., Albuquerque, NM (United States)

1993-11-01T23:59:59.000Z

403

Management of the aging of critical safety-related concrete structures in light-water reactor plants  

SciTech Connect

The Structural Aging Program has the overall objective of providing the USNRC with an improved basis for evaluating nuclear power plant safety-related structures for continued service. The program consists of a management task and three technical tasks: materials property data base, structural component assessment/repair technology, and quantitative methodology for continued-service determinations. Objectives, accomplishments, and planned activities under each of these tasks are presented. Major program accomplishments include development of a materials property data base for structural materials as well as an aging assessment methodology for concrete structures in nuclear power plants. Furthermore, a review and assessment of inservice inspection techniques for concrete materials and structures has been complete, and work on development of a methodology which can be used for performing current as well as reliability-based future condition assessment of concrete structures is well under way. 43 refs., 3 tabs.

Naus, D.J.; Oland, C.B. (Oak Ridge National Lab., TN (USA)); Arndt, E.G. (Nuclear Regulatory Commission, Washington, DC (USA))

1990-01-01T23:59:59.000Z

404

Cost and Performance Report for the ASTD Reuse of Concrete Within DOE from D&D Projects  

SciTech Connect

This cost and performance report describes the Accelerated Site Technology Deployment project that developed the Protocol for Development of Authorized Release Limits for Concrete at U.S. DOE Sites, which identifies the steps for obtaining approval to reuse concrete from Deactivation and Decommissioning of facilities. This protocol compares the risk and cost of various disposition paths for the concrete and follows the authorized release approach described in the DOE's draft handbook, Controlling Release for Reuse or Recycle of Property Containing Residual Radioactive Material. This approach provides for the development of authorized release limits through a series of prescribed steps before approval for release is granted. A case study was also completed on a previously decommissioned facility.

Kamboj, S.; Arnish, J.; Chen, S. Y.; Phillips, Ann Marie; Meservey, Richard Harlan; Tripp, Julia Lynn

2000-09-01T23:59:59.000Z

405

A comparison of the fracture properties of conventional and polymer-modified two-layer asphalt concrete overlay systems  

E-Print Network (OSTI)

The problem of reflection cracking through the conventional asphalt concrete overlays has increased the need to find new materials which could resist cracking or fracture more effectively. It is for this reason that polymers (Styrelo are added to the neat asphalt to improve the fracture resisting properties of asphalt concrete. In this study three different asphalt concrete mixtures with and without polymer (Styrelf) were used to study their fracture toughness. With four different binders and different combinations of mixtures, 18 different overlay systems were tested for their fracture toughness. Each overlay was made up of two different layers with asphalt rich sand anti-fracture (SAF) mixture as the bottom layer. Fracture mechanics concepts were used to compare the fracture properties of polymer (Styrelo modified asphalt concrete with the corresponding conventional neat asphalt concrete. Rate of crack growth is correlated with the energy line J*-integral. Crack growth rates were determined from laboratory experiments conducted on TTI overlay tester. Analysis of the experimental results showed that crack growth rate and J*-integral are correlated. In this study it was observed that the relation between the fracture material constants log(A) and (n) is not linear. A new fracture material constant (S) relating to crack speed was developed. The relationship between log(A) and (n) was found to be linear when combined with constant (S). Results showed that this new material constant (S) could lead to a better characterization of fracture toughness. Crack speed when calculated using (S) has shown better correlation with the observed experimental fatigue life. It is speculated that this new material constant (S) could be related to healing of the asphalt concrete or the plasticity effects due to unloading of the sample in overlay test.

Reddy, Praveena Gutha

1996-01-01T23:59:59.000Z

406

VIRTUAL CONCRETE  

Science Conference Proceedings (OSTI)

... 3-D air void structure in mortars Particle shape for cement, sand, gravel ... materials for houses Roundness of glass beads for reflective lines on ...

2008-03-12T23:59:59.000Z

407

REAL-TIME IDENTIFICATION AND CHARACTERIZATION OF ASBESTOS AND CONCRETE MATERIALS WITH RADIOACTIVE CONTAMINATION  

SciTech Connect

Concrete and asbestos-containing materials were widely used in DOE building construction in the 1940s and 1950s. Over the years, many of these porous materials have been contaminated with radioactive sources, on and below the surface. To improve current practice in identifying hazardous materials and in characterizing radioactive contamination, an interdisciplinary team from Rensselaer has conducted research in two aspects: (1) to develop terahertz time-domain spectroscopy and imaging system that can be used to analyze environmental samples such as asbestos in the field, and (2) to develop algorithms for characterizing the radioactive contamination depth profiles in real-time in the field using gamma spectroscopy. The basic research focused on the following: (1) mechanism of generating of broadband pulsed radiation in terahertz region, (2) optimal free-space electro-optic sampling for asbestos, (3) absorption and transmission mechanisms of asbestos in THz region, (4) the role of asbestos sample conditions on the temporal and spectral distributions, (5) real-time identification and mapping of asbestos using THz imaging, (7) Monte Carlo modeling of distributed contamination from diffusion of radioactive materials into porous concrete and asbestos materials, (8) development of unfolding algorithms for gamma spectroscopy, and (9) portable and integrated spectroscopy systems for field testing in DOE. Final results of the project show that the combination of these innovative approaches has the potential to bring significant improvement in future risk reduction and cost/time saving in DOE's D and D activities.

XU, X. George; Zhang, X.C.

2002-05-10T23:59:59.000Z

408

Considerations in the evaluation of concrete structures for continued service in aged Nuclear Power Plants (NPPs)  

SciTech Connect

Currently, there are /approximately/119 commercial nuclear power plants (NPPs) in the US either under construction, operating at low-to-full power, or awaiting an operating license. Together, these units have a net generating capacity of /approximately/110 GW(e). Assuming no life extension of present facilities, the operating licenses for these plants will start to expire in the middle of the next decade with Yankee Rowe being the first plant to attain this status. Where it is noted that with no life extension of facilities, a potential loss of electrical generating capacity in excess of 75 GW(e) could occur during the time period 2006 to 2020 when the operating licenses of 80 to 90 NPPs are scheduled to expire. A potential timely and cost-effective solution to meeting future electricity demand, which has worked well for non-nuclear generating plants, is to extend the service life (operating licenses) of existing NPPs. Since the concrete components in these plants provide a vital safety function, any continued service considerations must include an in-depth assessment of the safety-related concrete structures. 7 refs.

Naus, D.; Marchbanks, M.; Oland, B.; Arndt, G.; Brown, T.

1989-01-01T23:59:59.000Z

409

www.mdpi.com/journal/ijms Fly Ash-based Geopolymer Lightweight Concrete Using Foaming Agent  

E-Print Network (OSTI)

Abstract: In this paper, we report the results of our investigation on the possibility of producing foam concrete by using a geopolymer system. Class C fly ash was mixed with an alkaline activator solution (a mixture of sodium silicate and NaOH), and foam was added to the geopolymeric mixture to produce lightweight concrete. The NaOH solution was prepared by dilute NaOH pellets with distilled water. The reactives were mixed to produce a homogeneous mixture, which was placed into a 50 mm mold and cured at two different curing temperatures (60 C and room temperature), for 24 hours. After the curing process, the strengths of the samples were tested on days 1, 7, and 28. The water absorption, porosity, chemical composition, microstructure, XRD and FTIR analyses were studied. The results showed that the sample which was cured at 60 C (LW2) produced the maximum compressive strength for all tests, (11.03 MPa, 17.59 MPa, and 18.19 MPa) for days 1, 7, and 28, respectively. Also, the water absorption and porosity of LW2 were reduced by 6.78 % and 1.22 % after 28 days, respectively. The SEM showed that the LW2 sample had a denser matrix than LW1. This was because LW2 was heat cured, which caused the

Mohd Mustafa; Al Bakri Abdullah; Kamarudin Hussin; Mohamed Bnhussain; Khairul Nizar Ismail; Zarina Yahya; Rafiza Abdul Razak

2012-01-01T23:59:59.000Z

410

Analytical Results Of MOX Colemanite Concrete Sample PBC-44.2  

SciTech Connect

The Mixed Oxide Fuel Fabrication Facility (MFFF) will use colemanite bearing concrete neutron absorber panels credited with attenuating neutron flux in the criticality design analyses and shielding operators from radiation. The Savannah River National Laboratory is tasked with measuring the total density, partial hydrogen density, and partial boron density of the colemanite concrete. Sample PBC-44.2 was received on 9/20/2012 and analyzed. The average total density measured by the ASTM method C 642 was 2.03 g/cm{sup 3}, within the lower bound of 1.88 g/cm{sup 3}. The average partial hydrogen density was 6.64E-02 g/cm{sup 3} as measured using method ASTM E 1311 and met the lower bound of 6.04E-02 g/cm{sup 3}. The average measured partial boron density was 1.97E-01 g/cm{sup 3} which met the lower bound of 1.65E-01 g/cm{sup 3} measured by the ASTM C 1301 method.

Cozzi, A. D.; Best, D. R.; Reigel, M. M.

2012-10-18T23:59:59.000Z

411

ANALYTICAL RESULTS OF MOX COLEMANITE CONCRETE SAMPLE PBC-44.2  

SciTech Connect

The Mixed Oxide Fuel Fabrication Facility (MFFF) will use colemanite bearing concrete neutron absorber panels credited with attenuating neutron flux in the criticality design analyses and shielding operators from radiation. The Savannah River National Laboratory is tasked with measuring the total density, partial hydrogen density, and partial boron density of the colemanite concrete. Sample PBC-44.2 was received on 9/20/2012 and analyzed. The average total density measured by the ASTM method C 642 was 2.03 g/cm{sup 3}, within the lower bound of 1.88 g/cm3. The average partial hydrogen density was 6.64E-02 g/cm{sup 3} as measured using method ASTM E 1311 and met the lower bound of 6.04E-02 g/cm{sup 3}. The average measured partial boron density was 1.70E-01 g/cm{sup 3} which met the lower bound of 1.65E-01 g/cm{sup 3} measured by the ASTM C 1301 method.

Best, D.; Cozzi, A.; Reigel, M.

2012-12-20T23:59:59.000Z

412

ANALYTICAL RESULTS OF MOX COLEMANITE CONCRETE SAMPLES POURED AUGUST 29, 2012  

SciTech Connect

The Mixed Oxide Fuel Fabrication Facility (MFFF) will use colemanite bearing concrete neutron absorber panels credited with attenuating neutron flux in the criticality design analyses and shielding operators from radiation. The Savannah River National Laboratory is tasked with measuring the total density, partial hydrogen density, and partial boron density of the colemanite concrete. Samples poured 8/29/12 were received on 9/20/2012 and analyzed. The average total density of each of the samples measured by the ASTM method C 642 was within the lower bound of 1.88 g/cm{sup 3}. The average partial hydrogen density of samples 8.6.1, 8.7.1, and 8.5.3 as measured using method ASTM E 1311 met the lower bound of 6.04E-02 g/cm{sup 3}. The average measured partial boron density of each sample met the lower bound of 1.65E-01 g/cm{sup 3} measured by the ASTM C 1301 method. The average partial hydrogen density of samples 8.5.1, 8.6.3, and 8.7.3 did not meet the lower bound. The samples, as received, were not wrapped in a moist towel as previous samples and appeared to be somewhat drier. This may explain the lower hydrogen partial density with respect to previous samples.

Best, D.; Cozzi, A.; Reigel, M.

2012-12-20T23:59:59.000Z

413

ANALYTICAL RESULTS OF MOX COLEMANITE CONCRETE SAMPLE PBC-44.2  

Science Conference Proceedings (OSTI)

The Mixed Oxide Fuel Fabrication Facility (MFFF) will use colemanite bearing concrete neutron absorber panels credited with attenuating neutron flux in the criticality design analyses and shielding operators from radiation. The Savannah River National Laboratory is tasked with measuring the total density, partial hydrogen density, and partial boron density of the colemanite concrete. Sample PBC-44.2 was received on 9/20/2012 and analyzed. The average total density measured by the ASTM method C 642 was 2.03 g/cm{sup 3}, within the lower bound of 1.88 g/cm{sup 3}. The average partial hydrogen density was 6.64E-02 g/cm{sup 3} as measured using method ASTM E 1311 and met the lower bound of 6.04E-02 g/cm{sup 3}. The average measured partial boron density was 1.97E-01 g/cm{sup 3} which met the lower bound of 1.65E-01 g/cm{sup 3} measured by the ASTM C 1301 method.

Cozzi, A.; Best, D.; Reigel, M.

2012-10-18T23:59:59.000Z

414

Use of Brazilian sugarcane bagasse ash in concrete as sand replacement  

SciTech Connect

Sugarcane today plays a major role in the worldwide economy, and Brazil is the leading producer of sugar and alcohol, which are important international commodities. The production process generates bagasse as a waste, which is used as fuel to stoke boilers that produce steam for electricity cogeneration. The final product of this burning is residual sugarcane bagasse ash (SBA), which is normally used as fertilizer in sugarcane plantations. Ash stands out among agroindustrial wastes because it results from energy generating processes. Many types of ash do not have hydraulic or pozzolanic reactivity, but can be used in civil construction as inert materials. The present study used ash collected from four sugar mills in the region of Sao Carlos, SP, Brazil, which is one of the world's largest producers of sugarcane. The ash samples were subjected to chemical characterization, sieve analysis, determination of specific gravity, X-ray diffraction, scanning electron microscopy, and solubilization and leaching tests. Mortars and concretes with SBA as sand replacement were produced and tests were carried out: compressive strength, tensile strength and elastic modulus. The results indicated that the SBA samples presented physical properties similar to those of natural sand. Several heavy metals were found in the SBA samples, indicating the need to restrict its use as a fertilizer. The mortars produced with SBA in place of sand showed better mechanical results than the reference samples. SBA can be used as a partial substitute of sand in concretes made with cement slag-modified Portland cement.

Sales, Almir, E-mail: almir@ufscar.b [Department of Civil Engineering, UFSCar, Via Washington Luis, km 235, Monjolinho, 13565-905 Sao Carlos, SP (Brazil); Lima, Sofia Araujo, E-mail: sofiaalima@yahoo.com.b [Department of Civil Engineering, UFSCar, Via Washington Luis, km 235, Monjolinho, 13565-905 Sao Carlos, SP (Brazil)

2010-06-15T23:59:59.000Z

415

ANALYTICAL RESULTS OF MOX COLEMANITE CONCRETE SAMPLES POURED AUGUST 29, 2012  

SciTech Connect

The Mixed Oxide Fuel Fabrication Facility (MFFF) will use colemanite bearing concrete neutron absorber panels credited with attenuating neutron flux in the criticality design analyses and shielding operators from radiation. The Savannah River National Laboratory is tasked with measuring the total density, partial hydrogen density, and partial boron density of the colemanite concrete. Samples poured 8/29/12 were received on 9/20/2012 and analyzed. The average total density of each of the samples measured by the ASTM method C 642 was within the lower bound of 1.88 g/cm{sup 3}. The average partial hydrogen density of samples 8.6.1, 8.7.1, and 8.5.3 as measured using method ASTM E 1311 met the lower bound of 6.04E-02 g/cm{sup 3}. The average measured partial boron density of each sample met the lower bound of 1.65E-01 g/cm{sup 3} measured by the ASTM C 1301 method. The average partial hydrogen density of samples 8.5.1, 8.6.3, and 8.7.3 did not meet the lower bound. The samples, as received, were not wrapped in a moist towel as previous samples and appeared to be somewhat drier. This may explain the lower hydrogen partial density with respect to previous samples.

Cozzi, A.; Best, D.; Reigel, M.

2012-10-30T23:59:59.000Z

416

ANALYTICAL RESULTS OF MOX COLEMANITE CONCRETE SAMPLE POURED JULY 25, 2012 - CURED 28 DAYS  

SciTech Connect

The Mixed Oxide Fuel Fabrication Facility (MFFF) will use Colemanite bearing concrete neutron absorber panels credited with attenuating neutron flux in the criticality design analyses and shielding operators from radiation. The Savannah River National Laboratory is tasked with measuring the total density, partial hydrogen density, and partial boron density of the colemanite concrete. Samples 8.1.2, 8.2.2, 8.3.2, and 8.4.2 were received on 8/1/2012 and analyzed after curing for 28 days. The average total density measured by the ASTM method C 642 was 2.09 g/cm{sup 3}, within the lower bound of 1.88 g/cm{sup 3}. The average partial hydrogen density was 7.48E-02 g/cm{sup 3} as measured using method ASTM E 1311 and met the lower bound of 6.04E-02 g/cm{sup 3}. The average measured partial boron density was 1.71E-01 g/cm{sup 3} which met the lower bound of 1.65E-01 g/cm{sup 3} measured by the ASTM C 1301 method.

Cozzi, A. D.; Best, D. R.; Reigel, M. M.

2012-09-18T23:59:59.000Z

417

ANALYTICAL RESULTS OF MOX COLEMANITE CONCRETE SAMPLE POURED MAY 4, 2012  

DOE Green Energy (OSTI)

The Mixed Oxide Fuel Fabrication Facility (MFFF) will use Colemanite bearing concrete neutron absorber panels credited with attenuating neutron flux in the criticality design analyses. The Savannah River National Laboratory is tasked with measuring the total density, partial hydrogen density, and partial boron density of the colemanite concrete. Sample 04 May 12/Test/S1-1, S1-2, and S1-3 was received on 5/9/2012 and analyzed. The total density measure by the ASTM method C 642 was 2.00 g/cm{sup 3}, within the lower bound of 1.88 g/cm{sup 3}. The partial hydrogen density of 6.35E-02 g/cm{sup 3} as measured using method ASTM E 1311 met the lower bound of 6.04E-02 g/cm{sup 3}. The measured partial boron density of 1.88E-01 g/cm{sup 3} exceeded the lower bound of 1.65E-01 g/cm{sup 3} when the sodium peroxide fusion dissolution method was used in place of the prescribed ASTM C 1301 method.

Cozzi, A.; Best, D.; Reigel, M.

2012-06-14T23:59:59.000Z

418

CORCON-MOD3: An integrated computer model for analysis of molten core-concrete interactions. User`s manual  

SciTech Connect

The CORCON-Mod3 computer code was developed to mechanistically model the important core-concrete interaction phenomena, including those phenomena relevant to the assessment of containment failure and radionuclide release. The code can be applied to a wide range of severe accident scenarios and reactor plants. The code represents the current state of the art for simulating core debris interactions with concrete. This document comprises the user`s manual and gives a brief description of the models and the assumptions and limitations in the code. Also discussed are the input parameters and the code output. Two sample problems are also given.

Bradley, D.R.; Gardner, D.R.; Brockmann, J.E.; Griffith, R.O. [Sandia National Labs., Albuquerque, NM (United States)

1993-10-01T23:59:59.000Z

419

An assessment framework based on social perspectives and Analytic Hierarchy Process: A case study on sustainability in the Japanese concrete industry  

Science Conference Proceedings (OSTI)

This research introduces a framework for assessing concrete sustainability which is based upon the concept that technology is defined by stakeholders' perspectives and which applied Analytic Hierarchy Process to translate these perspectives into quantifiable ... Keywords: Analytic Hierarchy Process, Concrete, Construction, O31, O32, Sociology of technology, Sustainability

Michael Henry; Yoshitaka Kato

2011-10-01T23:59:59.000Z

420

Phyllosilicate orientation demonstrates early timing of compactional stabilization in calcite-cemented concretions in the Barnett Shale (Late Mississippian), Fort Worth  

E-Print Network (OSTI)

-cemented concretions in the Barnett Shale (Late Mississippian), Fort Worth Basin, Texas (U.S.A) Ruarri J. Day-Stirrat a in revised form 8 April 2008 Accepted 16 April 2008 Keywords: Barnett Shale Goniometry Concretions Fabric Calcite-cemented zones in the prolific gas-producing Barnett Shale (Ft. Worth Basin, Texas) preserve very

Note: This page contains sample records for the topic "rectangular precast concrete" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
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421

Project Title  

NLE Websites -- All DOE Office Websites (Extended Search)

Beneficial Use of CO Beneficial Use of CO 2 in Precast Concrete Production DE-FE0004285 Yixin Shao, Yaodong Jia Liang Hu McGill University 3H Company U.S. Department of Energy National Energy Technology Laboratory Carbon Storage R&D Project Review Meeting Developing the Technologies and Building the Infrastructure for CO 2 Storage August 21-23, 2012 Presentation outline * Goals and objectives * Benefits to the program * Project overview * Technical status * Accomplishment to date * Summary 2 Objective Masonry blocks Fiber-cement panels Prefabricated buildings Concrete pipes To develop a carbonation process to replace steam curing in precast concrete production for energy reduction, and carbon storage and utilization. Goals * CO 2 sequestration capacity by cement:

422

FRPRCS11 11th International Symposium on Fiber Reinforced Polymer for Reinforced Concrete Structures Guimares, June 26-28, 2013  

E-Print Network (OSTI)

area of the foam to concrete per line of FRP grid. Analysis of the measured data from 38 specimens to determine the shear flow capacity of the grid/foam shear mechanism as affected by different parameters grid is provided. 2. Increasing the thickness of the insulation decreased the shear flow capacity

423

Integrating Broad-Band High-Fidelity Acoustic Emission Sensors and Array Processing to Study Drying Shrinkage Cracking in Concrete  

E-Print Network (OSTI)

, cracks can create stress concentrations which can cause further cracking at loads which are well under energy released from the formation of a crack is converted into stress waves which in turn produce Shrinkage Cracking in Concrete Gregory C. McLaskeya,1 , Steven D. Glasera , Christian U. Grosseb

Glaser, Steven D.

424

Influence of content and particle size of waste pet bottles on concrete behavior at different w/c ratios  

SciTech Connect

The goal of this work was to study the mechanical behavior of concrete with recycled Polyethylene Therephtalate (PET), varying the water/cement ratio (0.50 and 0.60), PET content (10 and 20 vol%) and the particle size. Also, the influence of the thermal degradation of PET in the concrete was studied, when the blends were exposed to different temperatures (200, 400, 600 {sup o}C). Results indicate that PET-filled concrete, when volume proportion and particle size of PET increased, showed a decrease in compressive strength, splitting tensile strength, modulus of elasticity and ultrasonic pulse velocity; however, the water absorption increased. On the other hand, the flexural strength of concrete-PET when exposed to a heat source was strongly dependent on the temperature, water/cement ratio, as well as on the PET content and particle size. Moreover, the activation energy was affected by the temperature, PET particles location on the slabs and water/cement ratio.

Albano, C. [Universidad Central de Venezuela, Facultad de Ingenieria, Caracas (Venezuela, Bolivarian Republic of)], E-mail: carmen.albano@ucv.ve; Camacho, N. [Universidad Central de Venezuela, Facultad de Ingenieria, Caracas (Venezuela, Bolivarian Republic of)], E-mail: nelsoncamachog@gmail.com; Hernandez, M. [Universidad Simon Bolivar, Departamento de Mecanica, Caracas (Venezuela, Bolivarian Republic of); Matheus, A.; Gutierrez, A. [Universidad Central de Venezuela, Facultad de Ingenieria, Caracas (Venezuela, Bolivarian Republic of)

2009-10-15T23:59:59.000Z

425

Explicit/implicit multi-time step co-computations for blast analyses on a reinforced concrete frame structure  

Science Conference Proceedings (OSTI)

The paper explores the coupling between finite element codes based on implicit and explicit time integration schemes. An external coupling software has been developed based on the multi-time subdomain coupling algorithm, labelled as the GC method in ... Keywords: Blast loading, External code coupling, Reinforced concrete structure, Subdomain decomposition

M. Brun; A. Batti; A. Limam; A. Gravouil

2012-05-01T23:59:59.000Z

426

Cathodoluminescence microscopy and petrographic image analysis of aggregates in concrete pavements affected by alkali-silica reaction  

SciTech Connect

Various microscopic techniques (cathodoluminescence, polarizing and electron microscopy) were combined with image analysis with the aim to determine a) the modal composition and degradation features within concrete, and b) the petrographic characteristics and the geological types (rocks, and their provenance) of the aggregates. Concrete samples were taken from five different portions of Highway Nos. D1, D11, and D5 (the Czech Republic). Coarse and fine aggregates were found to be primarily composed of volcanic, plutonic, metamorphic and sedimentary rocks, as well as of quartz and feldspar aggregates of variable origins. The alkali-silica reaction was observed to be the main degradation mechanism, based upon the presence of microcracks and alkali-silica gels in the concrete. Use of cathodoluminescence enabled the identification of the source materials of the quartz aggregates, based upon their CL characteristics (i.e., color, intensity, microfractures, deformation, and zoning), which is difficult to distinguish only employing polarizing and electron microscopy. - Highlights: Black-Right-Pointing-Pointer ASR in concrete pavements on the Highways Nos. D1, D5 and D11 (Czech Republic). Black-Right-Pointing-Pointer Cathodoluminescence was combined with various microscopic techniques and image analysis. Black-Right-Pointing-Pointer ASR was attributed to aggregates. Black-Right-Pointing-Pointer Source materials of aggregates were identified based on cathodoluminescence characteristics. Black-Right-Pointing-Pointer Quartz comes from different volcanic, plutonic and metamorphic parent rocks.

Stastna, A., E-mail: astastna@gmail.com [Institute of Geochemistry, Mineralogy and Mineral Resources, Faculty of Science, Charles University in Prague, Albertov 6, 128 43 Praha 2 (Czech Republic); Sachlova, S.; Pertold, Z.; Prikryl, R. [Institute of Geochemistry, Mineralogy and Mineral Resources, Faculty of Science, Charles University in Prague, Albertov 6, 128 43 Praha 2 (Czech Republic); Leichmann, J. [Department of Geological Sciences, Faculty of Science, Masaryk University in Brno, Kotlarska 267/2, 611 37 Brno (Czech Republic)

2012-03-15T23:59:59.000Z

427

EVALUATION OF THE DURABILITY OF THE STRUCTURAL CONCRETE OF REACTOR BUILDINGS AT SRS  

Science Conference Proceedings (OSTI)

The Department of Energy (DOE) intends to close 100-150 facilities in the DOE complex using an in situ decommissioning (ISD) strategy that calls for grouting the below-grade interior volume of the structure and leaving the above-grade interior open or demolishing it and disposing of it in the slit trenches in E Area. These closures are expected to persist and remain stable for centuries, but there are neither facility-specific monitoring approaches nor studies on the rate of deterioration of the materials used in the original construction or on the ISD components added during closure (caps, sloped roofs, etc). This report will focus on the evaluation of the actual aging/degradation of the materials of construction used in the ISD structures at Savannah River Site (SRS) above grade, specifically P & R reactor buildings. Concrete blocks (six 2 to 5 ton blocks) removed from the outer wall of the P Reactor Building were turned over to SRNL as the first source for concrete cores. Larger cores were received as a result of grouting activities in P and R reactor facilities. The cores were sectioned and evaluated using microscopy, x-ray diffraction (XRD), ion chromatography (IC) and thermal analysis. Scanning electron microscopy shows that the aggregate and cement phases present in the concrete are consistent with the mix design and no degradation mechanisms are evident at the aggregate-cement interfaces. Samples of the cores were digested and analyzed for chloride ingress as well as sulfate attack. The concentrations of chloride and sulfate ions did not exceed the limits of the mix design and there is no indication of any degradation due to these mechanisms. Thermal analysis on samples taken along the longitudinal axis of the cores show that there is a 1 inch carbonation layer (i.e., no portlandite) present in the interior wall of the reactor building and a negligible carbonation layer in the exterior wall. A mixed layer of carbonate and portlandite extends deeper into the interior (2-3 inches) and exterior (1-2 inches) walls. This is more extensive than measured in previous SRS structures. Once the completely carbonated layer reaches the rebar that is approximately 2-3 inches into the concrete wall, the steel is susceptible to corrosion. The growth rate of the carbonated layer was estimated from current observations and previous studies. Based on the estimated carbonation rate, the steel rebar should be protected from carbonation induced corrosion for at least another 100 years. If degradation of these structures is dominated by the carbonation mechanism, the length of time before water intrusion is expected into the process room of P-reactor is estimated to be between 425-675 years.

Duncan, A.; Reigel, M.

2011-02-28T23:59:59.000Z

428

Monitoring the Durability Performance of Concrete in Nuclear Waste Containment. Technical Progress Report No. 4  

Science Conference Proceedings (OSTI)

OAK-B135 Monitoring the Durability Performance of Concrete in Nuclear Waste Containment. Technical Progress Report No. 4. The analysis of the effect of cracks on the acceleration of the calcium leaching process of cement-based materials has been pursued. During the last period (Technical Progress Report No 3), we have introduced a modeling accounting for the high diffusivity of fractures in comparison with the weak solid material diffusivity. It has been shown through dimensional and asymptotic analysis that small fractures do not significantly accelerate the material aging process. This important result for the overall structural aging kinetics of containment structure has been developed in a paper submitted to the international journal ''Transport in Porous Media''.

Ulm, Franz-Josef

2000-06-30T23:59:59.000Z

429

Characterizing the nano and micro structure of concrete to improve its durability  

Science Conference Proceedings (OSTI)

New and advanced methodologies have been developed to characterize the nano and microstructure of cement paste and concrete exposed to aggressive environments. High resolution full-field soft X-ray imaging in the water window is providing new insight on the nano scale of the cement hydration process, which leads to a nano-optimization of cement-based systems. Hard X-ray microtomography images on ice inside cement paste and cracking caused by the alkali-silica reaction (ASR) enables three-dimensional structural identification. The potential of neutron diffraction to determine reactive aggregates by measuring their residual strains and preferred orientation is studied. Results of experiments using these tools will be shown on this paper.

Monteiro, P.J.M.; Kirchheim, A.P.; Chae, S.; Fischer, P.; MacDowell, A.A.; Schaible, E.; Wenk, H.R.

2008-10-22T23:59:59.000Z

430

Characterizing the Nano and Micro Structure of Concrete toImprove its Durability  

Science Conference Proceedings (OSTI)

New and advanced methodologies have been developed to characterize the nano and microstructure of cement paste and concrete exposed to aggressive environments. High resolution full-field soft X-ray imaging in the water window is providing new insight on the nano scale of the cement hydration process, which leads to a nano-optimization of cement-based systems. Hard X-ray microtomography images of ice inside cement paste and cracking caused by the alkali?silica reaction (ASR) enables three-dimensional structural identification. The potential of neutron diffraction to determine reactive aggregates by measuring their residual strains and preferred orientation is studied. Results of experiments using these tools are shown on this paper.

Monteiro, P.J.M.; Kirchheim, A.P.; Chae, S.; Fischer, Peter; MacDowell, Alastair; Schaible, Eirc; Wenk, H.R.; Macdowell, Alastair A.

2009-01-13T23:59:59.000Z

431

Evaluation of concrete masonry unit walls for lateral natural phenomena hazards loads  

Science Conference Proceedings (OSTI)

Older single-story facilities (Pre-1985 vintage) are commonly constructed of structural steel framing with concrete masonry unit (CMU) walls connected to columns and roof girders of the steel framing system. The CMU walls are designed for lateral wind and seismic loads (perpendicular to the wall) and transmit shear loads from the roof diaphragm to the foundation footings. The lateral loads normally govern their design. The structural framing system and the roof diaphragm system are straight forward when analyzing or upgrading the structure for NPH loads. Because of a buildings design vintage, probable use of empirical methodology, and poor design basis documentation (and record retention); it is difficult to qualify or upgrade CMU walls for lateral Natural Phenomena Hazards (NPH) loads in accordance with References 1, 2 and 3. This paper discusses three analytical approaches and/or techniques (empirical, working stress and yield line) to determine the collapse capacity of a laterally loaded CMU wall, and compares their results

Faires, W.E. Jr.

1996-03-08T23:59:59.000Z

432

Response of dual-purpose reinforced-concrete mass shelter. Project 30. 2 of Operation Plumbbob  

DOE Green Energy (OSTI)

A reinforced-concrete dual-purpose underground parking garage and personnel shelter designed for a long-duration incident pressure of 40 psi was tested. The shelter was exposed to shot Priscilla, an approx. 37-kt 700-ft balloon burst (June 24, 1957), at a ground range of 1600 ft (predicted 35-psi peak incident-pressure level). The recorded peak incident pressure at the shelter was approximately 39 psi. Postshot soil borings were made to obtain undisturbed samples for determining soil characteristics. Preshot and postshot field surveys were made to determine the total lateral and vertical displacement of the structure. The test structure provided adequate protection from the effects of the test device at the test GZ distance. Despite failure of the door sealing gasket, a rise in pressure in the interior did not exceed 1.0 psi. The flat-slab roof and supporting structure were more than adequate to resist the 39-psi peak incident test loading.

Cohen, E.; Laing, E.; Bottenhofer, A.

1961-04-01T23:59:59.000Z

433

Analysis of core-concrete interaction event with flooding for the Advanced Neutron Source reactor  

SciTech Connect

This paper discusses salient aspects of the methodology, assumptions, and modeling of various features related to estimation of source terms from an accident involving a molten core-concrete interaction event (with and without flooding) in the Advanced Neutron Source (ANS) reactor at the Oak Ridge National Laboratory. Various containment configurations are considered for this postulated severe accident. Several design features (such as rupture disks) are examined to study containment response during this severe accident. Also, thermal-hydraulic response of the containment and radionuclide transport and retention in the containment are studied. The results are described as transient variations of source terms, which are then used for studying off-site radiological consequences and health effects for the support of the Conceptual Safety Analysis Report for ANS. The results are also to be used to examine the effectiveness of subpile room flooding during this type of severe accident.

Kim, S.H.; Taleyarkhan, R.P.; Georgevich, V.; Navarro-Valenti, S.

1993-11-01T23:59:59.000Z

434

The Effect of Shear Wall Distribution on the Dynamics of Reinforced Concrete Structures  

Science Conference Proceedings (OSTI)

The inclusion of a soft storey in multistory concrete buildings is a feature gaining popularity in urban areas where land is of exorbitant cost. In earthquake prone zones, this feature has been observed in post earthquake investigations. Although engineers are prepared to accept the notion that a soft storey poses a weak link in Seismic Design, yet the idea demands better understanding. The following study illustrates the importance of the judicious distribution of shear walls. The selected building is analyzed through nine numerical models which address the behavior of framed structures. The parameters discussed include, inter alias, the fundamental period of vibration, lateral displacements, axial and shear forces. It is noticed that an abrupt change in stiffness between the soft storey and the level above is responsible for increasing the strength demand on first storey columns. Extending the elevator shafts throughout the soft storey is strongly recommended.

Helou, S. H.; Touqan, A. R. [Civil Engineering Department, An-Najah National University, Nablus-Palestine (Country Unknown)

2008-07-08T23:59:59.000Z

435

Insulating LNG (liquified natural gas) storage tank containment dikes with a lightweight polymer concrete  

SciTech Connect

The natural gas industry has always been concerned ith accidental spills of liquified natural gas (LNG) from storage tanks into surrounding containment dikes. The LNG that is leaked to the dike area boils off and the vapors mix with the atmosphere forming a hazardous explsoive mixture within the dike walls. These hazardous mixtures can travel long distances into industrial or residential areas surroungind LNG storage facilities. Studies by the natural gas industry indicate that the hazards associated with accidental spills of LNG from storage tanks can be makedly reduced by insulating the diked areas surrounding these tanks. In this manner, the heat transfer from the dike surface to the LNG is reduced. The insulating composite is used to construct a thermal barrier between the walls and floor of the dike an the spilled LNG. The thermal conductivity, porosity, and compression strength of a concrete, polymer composite insulating material is discussed. 6 refs., 8 figs., 5 tbs.

Fontana, J.J.

1987-08-01T23:59:59.000Z

436

ASSESSMENT OF 90SR AND 137CS PENETRATION INTO REINFORCED CONCRETE (EXTENT OF 'DEEPENING') UNDER NATURAL ATMOSPHERIC CONDITIONS  

SciTech Connect

When assessing the feasibility of remediation following the detonation of a radiological dispersion device or improvised nuclear device in a large city, several issues should be considered including the levels and characteristics of the radioactive contamination, the availability of resources required for decontamination, and the planned future use of the city's structures and buildings. Currently, little is known about radionuclide penetration into construction materials in an urban environment. Knowledge in this area would be useful when considering costs of a thorough decontamination of buildings, artificial structures, and roads in an affected urban environment. Pripyat, a city substantially contaminated by the Chernobyl Nuclear Power Plant accident in April 1986, may provide some answers. The main objective of this study was to assess the depth of {sup 90}Sr and {sup 137}Cs penetration into reinforced concrete structures in a highly contaminated urban environment under natural weather conditions. Thirteen reinforced concrete core samples were obtained from external surfaces of a contaminated building in Pripyat. The concrete cores were drilled to obtain sample layers of 0-5, 5-10, 10-15, 15-20, 20-30, 30-40, and 40-50 mm. Both {sup 90}Sr and {sup 137}Cs were detected in the entire 0-50 mm profile of the reinforced cores sampled. In most of the cores, over 90% of the total {sup 137}Cs inventory and 70% of the total {sup 90}Sr inventory was found in the first 0-5 mm layer of the reinforced concrete. {sup 90}Sr had penetrated markedly deeper into the reinforced concrete structures than {sup 137}Cs.

Farfan, E.; Jannik, T.

2011-10-01T23:59:59.000Z

437

Evaluation of the filler effects on fatique cracking and permanent deformation of asphalt concrete mixtures  

E-Print Network (OSTI)

The addition of hydrated lime to asphalt has shown to be beneficial with an improvement in the Theological properties of the binder, as well as resistance to permanent deformation (rutting) and fatigue cracking of asphalt concrete mixtures. The addition of hydrated lime produces a filler effect where the result is a stiffening of the asphalt mixture, thus improving the resistance to permanent deformation. The fatigue characteristics of the asphalt mixtures did not worsen from this stiffening effect, but were either improved or similar. The Superpave Performance Grade was not significantly indicative of the filler effects induced by the hydrated lime. However, evaluation of the physical properties, G*/sin5 and G*sin5 were indicative of significant filler effects induced by the hydrated lime. Creep properties, stiffness and m-value showed no substantial change with the addition of lime. The use of 10 to 20% mass concentration of hydrated lime can effectively improve the rutting resistance of the unaged and aged binder with little practical effect on the low temperature and fatigue properties. The filler effects produced through the addition of hydrated lime to the asphalt yielded asphalt mixtures less susceptible to rutting. In most cases, the fatigue life of the asphalt mixtures improved as well. The reference modulus and creep compliance of the asphalt mixtures with lime had shown to have greater fatigue life. In most cases, Stone Matrix Asphalt (SMA) mixtures with lime showed greater resistance to rutting, as well as greater fatigue life. The filler effects from the hydrated lime, as well as the stone-on-stone contact and stiffening from the mastic (two characteristics of SMA mixtures) improved these properties. The addition of hydrated lime to asphalt improved the G*/sin5 and G*sin8 of the asphalt binders. The use of these asphalt binders in asphalt concrete mixtures increased the resistance to rutting and fatigue life. It is apparent that a correlation exists between the asphalt binder and mixture test results.

Izzo, Richard P

1997-01-01T23:59:59.000Z

438

State Environmental Policy Act (SEPA) environmental checklist forms for 304 Concretion Facility Closure Plan. Revision 2  

SciTech Connect

The 300 Area of the Hanford Site contains reactor fuel manufacturing facilities and several research and development laboratories. Recyclable scrap uranium with zircaloy-2 and copper silicon alloy, uranium-titanium alloy, beryllium/zircaloy-2 alloy, and zircaloy-2 chips and fines were secured in concrete billets (7.5-gallon containers) in the 304 Facility, located in the 300 Area. The beryllium/zircaloy-2 alloy and zircaloy-2 chips and fines are designated as mixed waste with the characteristic of ignitability. The concretion process reduced the ignitability of the fines and chips for safe storage and shipment. This process has been discontinued and the 304 Facility is now undergoing closure as defined in the Resource Conservation and Recovery Act (RCRA) of 1976 and the Washington Administrative Code (WAC) Dangerous Waste Regulations, WAC 173-303-040. This closure plan presents a description of the 304 Facility, the history of materials and waste managed, and the procedures that will be followed to close the 304 Facility. The 304 Facility is located within the 300-FF-3 (source) and 300-FF-5 (groundwater) operable units, as designated in the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement) (Ecology et al. 1992). Contamination in the operable units 300-FF-3 and 300-FF-5 is scheduled to be addressed through the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) of 1980 remedial action process. Therefore, all soil remedial action at the 304 Facility will be conducted as part of the CERCLA remedial action of operable units 300-FF-3 and 300-FF-5.

Not Available

1993-11-01T23:59:59.000Z

439

A novel technique for the production of cool colored concrete tile and asphalt shingle roofing products  

SciTech Connect

The widespread use of solar-reflective roofing materials can save energy, mitigate urban heat islands and slow global warming by cooling the roughly 20% of the urban surface that is roofed. In this study we created prototype solar-reflective nonwhite concrete tile and asphalt shingle roofing materials using a two-layer spray coating process intended to maximize both solar reflectance and factory-line throughput. Each layer is a thin, quick-drying, pigmented latex paint based on either acrylic or a poly(vinylidene fluoride)/acrylic blend. The first layer is a titanium dioxide rutile white basecoat that increases the solar reflectance of a gray-cement concrete tile from 0.18 to 0.79, and that of a shingle surfaced with bare granules from 0.06 to 0.62. The second layer is a 'cool' color topcoat with weak near-infrared (NIR) absorption and/or strong NIR backscattering. Each layer dries within seconds, potentially allowing a factory line to pass first under the white spray, then under the color spray. We combined a white basecoat with monocolor topcoats in various shades of red, brown, green and blue to prepare 24 cool color prototype tiles and 24 cool color prototypes shingles. The solar reflectances of the tiles ranged from 0.26 (dark brown; CIELAB lightness value L* = 29) to 0.57 (light green; L* = 76); those of the shingles ranged from 0.18 (dark brown; L* = 26) to 0.34 (light green; L* = 68). Over half of the tiles had a solar reflectance of at least 0.40, and over half of the shingles had a solar reflectance of at least 0.25.

Levinson, Ronnen; Akbari, Hashem; Berdahl, Paul; Wood, Kurt; Skilton, Wayne; Petersheim, Jerry

2009-11-20T23:59:59.000Z

440

Investigation of the use of fly-ash based autoclaved cellular concrete blocks in coal mines for air duct work. Final report, January 25, 1993--December 31, 1994  

SciTech Connect

Coal mines are required to provide ventilation to occupied portions of underground mines. Concrete block is used in this process to construct air duct walls. However, normal concrete block is heavy and not easy to work with and eventually fails dramatically after being loaded due to mine ceiling convergence and/or floor heave. Autoclaved cellular concrete block made from (70{plus_minus}%) coal fly ash is lightweight and less rigid when loaded. It is lighter and easier to use than regular concrete block for underground mine applications. It has also been used in surface construction around the world for over 40 years. Ohio Edison along with eight other electric utility companies, the Electric Power Research Institute (EPRI), and North American Cellular Concrete constructed a mobile demonstration plant to produce autoclaved cellular concrete block from utility fly ash. To apply this research in Ohio, Ohio Edison also worked with the Ohio Coal Development Office and CONSOL Inc. to produce autoclaved cellular concrete block not only from coal ash but also from LIMB ash, SNRB ash, and PFBC ash from various clean coal technology projects sponsored by the Ohio Coal Development Office. The purpose of this project was to demonstrate the potential for beneficial use of fly ash and clean coal technology by-products in the production of lightweight block.

Horvath, M.L. [Ohio Edison Co., Akron, OH (United States)

1995-06-19T23:59:59.000Z

Note: This page contains sample records for the topic "rectangular precast concrete" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Performance-based approach to evaluate alkali-silica reaction potential of aggregate and concrete using dilatometer method  

E-Print Network (OSTI)

The undesirable expansion of concrete because of a reaction between alkalis and certain type of reactive siliceous aggregates, known as alkali-silica reactivity (ASR), continues to be a major problem across the entire world. The renewed interest to minimize distress resulting from ASR has emphasized the need to develop predictable modeling of concrete ASR behavior under field conditions. Current test methods are either incapable or need long testing periods in which to only offer rather limited predictive estimates of ASR behavior in a narrow and impractical band of field conditions. Therefore, an attempt has been made to formulate a robust performance approach based upon basic properties of aggregate and concrete ASR materials derived from dilatometry and a kinetic-based mathematical expressions for ASR behavior. Because ASR is largely an alkali as well as a thermally activated process, the use of rate theory (an Arrhenius relationship between temperature and the alkali solution concentration) on the dilatometer time-expansion relationship, provides a fundamental aggregate ASR material property known as activation energy. Activation energy is an indicator of aggregate reactivity which is a function of alkalinity, particle size, crystallinity, calcium concentration, and others. The studied concrete ASR material properties represent a combined effects of mixture related properties (e.g., water-cementitious ratio, porosity, presence of supplementary cementitious materials, etc.) and maturity. Therefore, the proposed performance-based approach provides a direct accountability for a variety of factors that affect ASR, such as aggregate reactivity (activation energy), temperature, moisture, calcium concentration, solution alkalinity, and water-cementitious material ratio. Based on the experimental results, the following conclusion can be drawn concerning the performance-based approach to evaluate ASR potential of aggregate and concrete using dilatometer method; (i) the concept of activation energy can be used to represent the reactivity of aggregate subjected to ASR, (ii) the activation energy depends on the reactivity of aggregate and phenomenological alkalinity of test solution, and (iii) The proposed performance-based model provides a means to predict ASR expansion development in concrete.

Shon, Chang Seon

2008-05-01T23:59:59.000Z

442

OECD MCCI project long-term 2-D molten core concrete interaction test design report, Rev. 0. September 30, 2002.  

Science Conference Proceedings (OSTI)

The Melt Attack and Coolability Experiments (MACE) program at Argonne National Laboratory addressed the issue of the ability of water to cool and thermally stabilize a molten core-concrete interaction when the reactants are flooded from above. These tests provided data regarding the nature of corium interactions with concrete, the heat transfer rates from the melt to the overlying water pool, and the role of noncondensable gases in the mixing processes that contribute to melt quenching. As a follow-on program to MACE, The Melt Coolability and Concrete Interaction Experiments (MCCI) project is conducting reactor material experiments and associated analysis to achieve the following two technical objectives: (1) resolve the ex-vessel debris coolability issue through a program that focuses on providing both confirmatory evidence and test data for the coolability mechanisms identified in MACE integral effects tests, and (2) address remaining uncertainties related to long-term two-dimensional molten core-concrete interactions under both wet and dry cavity conditions. Achievement of these two objectives will demonstrate the efficacy of severe accident management guidelines for existing plants, and provide the technical basis for better containment designs for future plants. In terms of the first program objective, the Small-Scale Water Ingression and Crust Strength (SSWICS) test series has been initiated to provide fundamental information on the ability of water to ingress into cracks and fissures that form in the debris during quench, thereby augmenting the otherwise conduction-limited heat transfer process. A test plan for Melt Eruption Separate Effects Tests (MESET) has also been developed to provide information on the extent of crust growth and melt eruptions as a function of gas sparging rate under well-controlled experiment conditions. In terms of the second program objective, the project Management Board (MB) has approved startup activities required to carry out experiments to address remaining uncertainties related to long-term two-dimensional molten core-concrete interaction. In particular, for both wet and dry cavity conditions, there is uncertainty insofar as evaluating the lateral vs. axial power split during a core-concrete interaction due to a lack of experiment data. As a result, there are differences in the 2-D cavity erosion predicted by codes such as MELCOR, WECHSL, and COSACO. The first step towards generating this data is to produce a test plan for review by the Project Review Group (PRG). The purpose of this document is to provide this plan.

Farmer, M. T.; Kilsdonk, D. J.; Lomperski, S.; Aeschliman, R. W.; Basu, S. (Nuclear Engineering Division); (NRC)

2011-05-23T23:59:59.000Z

443

STORAGE OF HEAT AND COOLTH IN HOLLOW-CORE CONCRETE SLABS. SWEDISH EXPERIENCE, AND APPLICATION TO LARGE, AMERICAN-STYLE BUILDINGS  

E-Print Network (OSTI)

different slabs, each with a heat capacity of 100 Wh/m2~ Thefloor slabs have a large heat capacity (100 Wh/m2K - where Krequired, but the concrete heat capacity will still handle

Andersson, L.O.

2011-01-01T23:59:59.000Z

444

Assessment of FRP composite strengthened reinforced concrete bridge structures at the component and systems level through progressive damage and Non-Destructive Evaluation (NDE)  

E-Print Network (OSTI)

of Concrete Floor Slabs by Carbon Fiber Textiles, Compositeof R/C Beams with Carbon Fiber Sheets, ASCE Journal ofBeam-Column Joints Using Carbon Fiber- Reinforced Polymers,

Ghosh, Kumar Kanti

2006-01-01T23:59:59.000Z

445

Use of recycled chunk rubber asphalt concrete (CRAC) on low volume roads and use of recycled crumb rubber modifier in asphalt pavements. Final report, June 1993-June 1995  

SciTech Connect

The major objective of this project was to formulate a Chunk Rubber Asphalt Concrete (CRAC) mix for use on low volume roads. CRAC is a rubber modified asphalt concrete product produced by the `dry process` where rubber chunks of 1/2 inch size are used as aggregate in a cold mix with a type C fly ash. The second objective of this project was to develop guidelines concerning the use of rubber modified asphalt concrete hot mix to include: (1) Design methods for use of asphalt-rubber mix for new construction and overlay, (2) Mix design method for asphalt-rubber, and (3) Test method for determining the amount of rubber in an asphalt-rubber concrete for quality control purposes.

Hossain, M.; Funk, L.P.; Sadeq, M.A.; Marucci, G.

1995-06-01T23:59:59.000Z

446

Eighth CANMET/ACI International Conference on Fly Ash, Silica Fume, Slag, and Natural Pozzolans in Concrete  

Science Conference Proceedings (OSTI)

The nine papers in this CD are collected by the U. S. Advisory Committee for presentation at the Eighth CANMET/ACI International Conference on Fly Ash, Silica Fume, Slag, and Natural Pozzolans in Concrete, May 2329, 2004, Las Vegas, Nevada. They are being published by EPRI, Palo Alto, CA to make them available to all attendees, and other interested people, in a compact form for future reference and use.

2004-05-05T23:59:59.000Z

447

Safety evaluation for packaging (onsite) for the concrete-shielded RH TRU drum for the 327 Postirradiation Testing Laboratory  

SciTech Connect

This safety evaluation for packaging authorizes onsite transport of Type B quantities of radioactive material in the Concrete Shielded Remote-Handled Transuranic Waste (RH TRU) Drum per HNF-PRO-154, Responsibilities and Procedures for all Hazardous Material Shipments. The drum will be used for transport of 327 Building legacy waste from the 300 Area to a solid waste storage facility on the Hanford Site.

Smith, R.J.

1998-03-31T23:59:59.000Z

448

Modular Accident Analysis Program, Version 5, Molten CoriumConcrete Interaction and Debris Coolability Model Enhancement Description  

Science Conference Proceedings (OSTI)

This report describes proposed enhancements to the Modular Accident Analysis Program (MAAP) molten coriumconcrete interaction (MCCI) model. MAAP is a computer program that simulates the operation of light-water and heavy-water moderated nuclear power plants for both current and advanced light-water reactor designs.Engineers at Fukushima observed that water pumped into the reactor vessel rose to a certain height, but it did not rise further as more water was pumped into the reactor ...

2013-02-28T23:59:59.000Z

449

Safety evaluation for packaging (onsite) for concrete-shielded RHTRU waste drum for the 327 postirradiation testing laboratory  

Science Conference Proceedings (OSTI)

This safety evaluation for packaging authorizes onsite transport of Type B quantities of radioactive material in the Concrete- Shielded Remote-Handled Transuranic Waste (RH TRU) Drum per WHC-CM-2-14, Hazardous Material Packaging and Shipping. The drum will be used for transport of 327 Building legacy waste from the 300 Area to the Transuranic Waste Storage and Assay Facility in the 200 West Area and on to a Solid Waste Storage Facility, also in the 200 Area.

Adkins, H.E.

1996-10-29T23:59:59.000Z

450

ASSESSMENT OF RADIONUCLIDE RELEASE FROM INTACT STRUCTURES BACKFILLED WITH CONTAMINATED CONCRETE AT THE YANKEE NUCLEAR POWER STATION.  

SciTech Connect

This calculation determines the release of residual radioactivity (including H-3, C-14, Co-60, Ni-63, Sr-90, and Cs-137), from subsurface structures filled with concrete debris at the Yankee Nuclear Power Station. Analyses were performed to assess the rate of release from the source of contamination and the resulting dose in the groundwater pathway. Two mechanisms were considered, diffusive release from the concrete structures (walls and floors) that remain intact and sorption onto concrete backfill placed within these structures. RESRAD was used to calculate the predicted maximum dose assuming a unit loading of 1 pCi/g on the intact structures. To the extent possible, the same assumptions in the soil DCGL calculations performed for Yankee Atomic were used in the calculation. However, modifications to some input parameter values were needed to represent the geometry of the subsurface facilities, flow through these facilities, and releases from the backfill and intact structures. Input parameters specific to these calculations included the leach rate, disposal geometry, pumping rate, porosity and bulk density. The dose results for a unit loading of 1 pCi/g on intact structures showed that Sr-90 had the highest dose (3.67E-02 mrem/yr).

SULLIVAN, T.

2004-09-30T23:59:59.000Z

451

Nonlinear finite-element analysis of a reinforced-concrete Mark III containment under pressure and gravity loads. [BWR  

DOE Green Energy (OSTI)

An analysis of a Mark III reactor containment vessel subjected to a uniformly increasing internal pressure and gravity loads is carried out in order to ascertain the load carrying capacity of the structure under hydrogen burn. The analysis is conducted by using a nonlinear finite element model that includes nonlinearities in the strain-displacement relations as well as in the material constitutive equations. In this analysis, the nonlinear behavior of the liner and reinforcement steels is described by a von Mises elastic-plastic model with isotropic hardening. A recently developed elastic-plastic-fracture model that includes both the cracking and crushing limit states is used for the plain concrete. Consistent smearing and de-smearing procedures are then used to represent the composite material properties of the reinforced concrete by an anisotropic and locally homogeneous continuum. Results pertaining to the critical regions of the containment where cracking of the concrete, yielding of the reinforcement bars, and substantial straining of the liner take place are discussed.

Sharma, S.; Reich, M.; Shteyngart, S.; Chang, T.Y.

1983-01-01T23:59:59.000Z

452

Effect of cumulative seismic damage and corrosion on life-cycle cost of reinforced concrete bridges  

E-Print Network (OSTI)

Bridge design should take into account not only safety and functionality, but also the cost effectiveness of investments throughout a bridge life-cycle. This work presents a probabilistic approach to compute the life-cycle cost (LCC) of corroding reinforced concrete (RC) bridges in earthquake prone regions. The approach is developed by combining cumulative seismic damage and damage associated to corrosion due to environmental conditions. Cumulative seismic damage is obtained from a low-cycle fatigue analysis. Chloride-induced corrosion of steel reinforcement is computed based on Ficks second law of diffusion. The proposed methodology accounts for the uncertainties in the ground motion parameters, the distance from source, the seismic demand on the bridge, and the corrosion initiation time. The statistics of the accumulated damage and the cost of repairs throughout the bridge life-cycle are obtained by Monte-Carlo simulation. As an illustration of the proposed approach, the effect of design parameters on the life-cycle cost of an example RC bridge is studied. The results are shown to be valuable in better estimating the condition of existing bridges (i.e., total accumulated damage at any given time) and, therefore, can help schedule inspection and maintenance programs. In addition, by taking into consideration the deterioration process over a bridge life-cycle, it is possible to make an estimate of the optimum design parameters by minimizing, for example, the expected cost throughout the life of the structure.

Kumar, Ramesh

2007-12-01T23:59:59.000Z

453

Insulating polymer concrete. [Perlite or glass nodule aggregates bound together with a polyester resin  

SciTech Connect

An insulating polymer concrete (IPC) composite has been developed under contract to the Gas Research Institute for possible use as a dike insulation material at Liquid Natural Gas (LNG) storage facilities. In the advent of an LNG spill into the impounding dike area, the boiloff rate of the LNG can be substantially reduced if the surfaces of the dike are insulated. This increased safety at the LNG facility will tend to reduce the hazardous explosive mixture with atmospheric air in the surrounding region. The dike insulation material must have a low thermal conductivity and be unaffected by environmental conditions. The IPC composites developed consist of perlite or glass nodule aggregates bound together as a closed cell structure with a polyester resin. In addition to low thermal conductivity and porosity, these composites have correspondingly high strengths and, therefore, can carry transient loads of workmen and maintenance equipment. Prefabricated IPC panels have been installed experimentally and at least one utility is currently considering a complete installation at its LNG facility. 4 references, 8 tables.

Fontana, J.J.

1984-04-01T23:59:59.000Z

454

Development of polymer concrete liners and coatings for use in geothermal applications  

DOE Green Energy (OSTI)

The results of a research and field testing program conducted by Brookhaven National Laboratory for the Geothermal Division of the US Department of Energy to develop polymer concrete (PC) liners and coatings for use in geothermal applications are presented. Whenever possible, carbon steel is used in geothermal facilities for components such as piping, well casings, and containment vessels. However carbon steel is subject to severe corrosion when exposed to some geothermal fluids and brines, leading to the use, in some cases, of very expensive high alloy steels. Results of laboratory tests done in simulated geothermal environments (pH 2 hydrochloric acid steam at 200{degree}C) have shown that PC materials can be used as liners and coatings to protect carbon steel surfaces from corrosion. In situ field testing of 8-in. (203-mm) inside diameter (ID) by 12-in. (305-mm) long spool sections and 12in. ID (305-mm) wellhead tee sections in operational geothermal facilities is currently being done to verify the laboratory test data. Economic studies have shown that the capital cost of the vessels and piping in a typical geothermal facility can be significantly reduced through the use of protective PC linings and coatings. As a result PC lined components are currently being used commercially at two geothermal sites.

Webster, R.P.; Reams, W.; Kukacka, L.E.

1993-09-01T23:59:59.000Z

455

DOE Solar Decathlon: Team New Jersey: Rutgers - The State University of  

NLE Websites -- All DOE Office Websites (Extended Search)

Jersey: Rutgers - The State University of New Jersey and New Jersey: Rutgers - The State University of New Jersey and New Jersey Institute of Technology Team New Jersey created a buzz at the U.S. Department of Energy Solar Decathlon 2011 with its ENJOY House, which was built of pre-cast concrete insulated panels. The house is currently in storage in southern New Jersey awaiting final reconstruction financing and approvals. Photo of ENJOY House. Enlarge image ENJOY House integrated solar technologies with passive strategies and contemporary architectural design in a house built of pre-cast concrete insulated panels. (Credit: