Impact load-induced micro-structural damage and micro-structure associated mechanical response of concrete made with different surface roughness and porosity aggregates

Journal Article · Wed Feb 15 00:00:00 EST 2012 · Cement and Concrete Research

DOI:https://doi.org/10.1016/j.cemconres.2011.09.015· OSTI ID:21596953

Erdem, Savas; Dawson, Andrew Robert; Thom, Nicholas Howard

The relationship between the nature of micro damage under impact loading and changes in mechanical behavior associated with different microstructures is studied for concretes made with two different coarse aggregates having significant differences mainly in roughness and porosity - sintered fly ash and uncrushed gravel. A range of techniques including X-ray diffraction, digital image analysis, mercury porosimetry, X-ray computed tomography, laser surface profilometry and scanning electron microscopy were used to characterize the aggregates and micro-structures. The concrete prepared with lightweight aggregates was stronger in compression than the gravel aggregate concrete due to enhanced hydration as a result of internal curing. In the lightweight concrete, it was deduced that an inhomogeneous micro-structure led to strain incompatibilities and consequent localized stress concentrations in the mix, leading to accelerated failure. The pore structure, compressibility, and surface texture of the aggregates are of paramount importance for the micro-cracking growth.

• OSTI ID: 21596953
• Journal Information: Cement and Concrete Research, Vol. 42, Issue 2; Other Information: DOI: 10.1016/j.cemconres.2011.09.015; PII: S0008-8846(11)00262-6; Copyright (c) 2011 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0008-8846
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COMPRESSIBILITY
COMPRESSION
COMPUTERIZED TOMOGRAPHY
CONCRETES
CRACKING
CURING
DAMAGE
FLY ASH
HYDRATION
IMAGE PROCESSING
PORE STRUCTURE
POROSITY
ROUGHNESS
SCANNING ELECTRON MICROSCOPY
STRAINS
STRESSES
SURFACES
TEXTURE
X-RAY DIFFRACTION
AEROSOL WASTES
ASHES
BUILDING MATERIALS
CHEMICAL REACTIONS
COHERENT SCATTERING
COMBUSTION PRODUCTS
DECOMPOSITION
DIAGNOSTIC TECHNIQUES
DIFFRACTION
ELECTRON MICROSCOPY
MATERIALS
MECHANICAL PROPERTIES
MICROSCOPY
MICROSTRUCTURE
PROCESSING
PYROLYSIS
RESIDUES
SCATTERING
SOLVATION
SURFACE PROPERTIES
THERMOCHEMICAL PROCESSES
TOMOGRAPHY
WASTES