Effect of mineral admixtures on alkali-silica reaction

Abstract

The influence of silica fume, slag and fly ash on alkali-silica reaction under the condition of 70 °C is studied. The results show that silica, slag and fly ash may inhibit alkali-silica reaction only under suitable content. When the content is less than 10%, silica fume does not markedly influence the expansion of alkalisilica reaction. When the content is 15%–20%, silica fume only may delay the expansion of alkali-silica reaction. When the content is 30%–70%, slag may only delay the expansion of alkali-silica reaction, but cannot inhibit the expansion of alkali-silica reaction. When the content is 10%, fly ash does not markedly influence the expansion of alkali-silica reaction. When the content is 20%–30%, fly ash may only delay the expansion of alkali-silica reaction, but cannot inhibit the expansion of alkali-silica reaction. When the content is over 50%, it is possible that fly ash can inhibit effectively alkali-silica reaction.

Keywords

mineral admixture / alkali-silica reaction / effectiveness

References

[1] Hobbs D. W. Alkali-Silica Reaction in Concrete[M], 1988. London: Thomas Telford Ltd.. 183

[2] ASTM C441. Standard Test Method for Effectiveness of Mineral Admixtures in Preventing Excessive Expansion of Concrete due to the Alkali-Aggregate Reaction[S]. 1981

[3] Hobbs D. W. Deleterious Expansion of Concrete due to Alkali-Silica Reaction: Influence of Fly Ash and Slag[J]. Magazine of Concrete Research, 1986, 38(137): 191-205.

[4] Hobbs D W. Effect of Mineral and Chemical Admixture on Alkali-Aggregate Reaction[C]. Proceedings of 8th International Conference on Alkali-Aggregate Reaction, Kyoto, 1989, 173–186