Mechanism of Using Mineral Admixtures in Concrete to Suppress Alkali-Silica Reaction

Abstract:

The mechanism of using mineral admixtures in concrete for suppressing alkali-silica reaction has been studied through analyzing pore solution and observing the surface of aggregates in mortar bars with scanning electron microscope (SEM). The results show that when mineral admixtures are used in the concrete, not only the alkali concentration in the pore solution can be reduced, but also the diffusion of alkali ions from the outside of concrete to the inside can be prevented, and the diffusion of alkali ions from the pore solution to the surface of the aggregates can also be prevented. Thus the attack of alkalis to aggregates is reduced, and the alkali-silica reaction is suppressed.

• Periodical: Key Engineering Materials (Volumes 302-303)
• Pages: 111-119
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.302-303.111
• Online since: January 2006
• Authors: Xiao Xin Feng, Nai Qian Feng
• Keywords: Alkali Silica Reaction (ASR), Concrete, Mineral Admixture, Suppressing Mechanism

References

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DOI: 10.1520/c1260-01

[2] ASTM C311-94b, Standard test methods for sampling and testing fly ash or natural pozzolans for use as a mineral admixture in Portland-cement concrete, Annual Book of ASTM Standards, Vol. 04. 02, 1995, pp.187-193.

DOI: 10.1520/c0311-00

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