Resistance of MgO–GGBS and CS–GGBS stabilised marine soft clays to sodium sulfate attack

Abstract

Reactive magnesia (MgO) and carbide slag (CS) were used to activate ground granulated blastfurnace slag (GGBS) to stabilise a marine soft clay, and the stabilised clays were subjected to accelerated sodium sulfate attack. The results indicated MgO–GGBS stabilised clay was nearly inert to this sodium sulfate solution. The resistance of CS–GGBS stabilised clay to sodium sulfate attack was lower than that of MgO–GGBS stabilised clay, but higher than that of Portland cement stabilised clay. Unlike CS–GGBS stabilised clay, there was no calcium aluminate hydrate or alumino-ferrite monosulfate produced in MgO–GGBS stabilised clay, and hence no ettringite, which would cause deterioration, formed when exposed to sodium sulfate.