Comparison of alkali-silica reaction mitigation between supersulfated cement and Portland cement

Abstract

Deleterious alkali-silica reaction (ASR) in concrete occurs between alkaline ions and reactive minerals present in aggregates. Studies with Portland cement (PC) have shown that alumina can help form a protective film that surrounds the aggregate and hinders the dissolution of reactive minerals and their consequent reaction with alkaline ions, preventing the formation of expansive gels. At the same time, calcium increases the expansive potential of alkali-silica reaction gels. Supersulfated cement (SSC) contains higher alumina and lower calcium content and can mitigate ASR. The objective of the present study was to evaluate the behavior of SSC subjected to ASR by the accelerated mortar bar test method and compare it with PC-based mortars. The results showed that the two compositions of SSC and the Brazilian PC_IV (with pozzolan) were considered resistant to ASR, while PC_V (without pozzolan) was characterized as potentially harmful.