Properties of Portland cement concrete containing fly ash and condensed silica-fume

Journal Article · Wed Sep 01 04:00:00 EDT 1982 · Cem. Concr. Res.; (United States)

DOI:https://doi.org/10.1016/0008-8846(82)90019-9· OSTI ID:6357039

Mehta, R K; Gjoerv, O E

Normal pozzolan additives, due to their low surface area and reactivity are not able to improve early strengths and durability of concrete. The problem can be solved by using a mixture of normal and highly reactive pozzolans, such as condensed silica-fume. Results of an investigation are reported here in which 30 percent portland cement in concrete was replaced by an equal volume of fly ash, condensed silica-fume, or a 50:50 mixture of the two. Sand-to-gravel proportions were adjusted to obtain workable concretes having the same water-cement ratio. Compared to the control concrete, the 7 and 28 days compressive strengths of the fly ash concretes were significantly lower; however, in the case of mixed-pozzolan addition, the 7-days strength was similar and the 28-days strength was higher. The differences in the pozzolanic activity of the additives were confirmed by a parallel investigation involving determination of free lime and pore-size distribution of the cement pastes. (6 refs.)

• OSTI ID: 6357039
• Journal Information: Cem. Concr. Res.; (United States), Journal Name: Cem. Concr. Res.; (United States) Vol. 12:5; ISSN CCNRA
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010800* -- Coal
Lignite
& Peat-- Waste Management
36 MATERIALS SCIENCE
360603 -- Materials-- Properties
ADDITIVES
AEROSOL WASTES
ASHES
BUILDING MATERIALS
CEMENTS
CHALCOGENIDES
COMPRESSION STRENGTH
CONCRETES
DISPERSIONS
FLY ASH
MATERIALS
MECHANICAL PROPERTIES
MINERALS
MIXTURES
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
PORTLAND CEMENT
RESIDUES
SILICA
SILICON COMPOUNDS
SILICON OXIDES
TESTING
WASTE PRODUCT UTILIZATION
WASTES