The mechanism of the effect of mineral admixtures on the expansion of alkali-silica reaction

Abstract

On the base of the influence rule of silica fume, slag and fl y ash on alkali-silica reaction under the condition of 70 °C, the mechanism of the effect of mineral admixtures on alkali-silica reaction is studied further in the paper. The results show that the effects of mineral admixtures on alkali-silica reaction are mainly chemistry effect and surface physichemistry effect. Under suitable condition, the chemistry effect may make alkali-silica reaction to be inhibited effectively, but the physichemistry effect only make alkali-silica reaction to be delayed. The chemistry effect and the physichemistry effect of minerals admixture are relative to the content of Ca(OH)₂ in system. Under the condition that there is a large quantity of Ca(OH)₂, mineral admixture cannot inhibit alkali-silica reaction effectively. Only when Ca(OH)₂ in the system is very less, it is possible that mineral admixture inhibits alkali-silica reaction effectively.

Keywords

mineral admixture / alkali-silica reaction / mechanism

References

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