Effect of internal curing by superabsorbent polymers – Internal relative humidity and autogenous shrinkage of alkali-activated slag mortars

This study experimentally investigated the effect of internal curing by superabsorbent polymers (SAPs) for mitigating autogenous shrinkage of alkali-activated slag (AAS) mortars. Measured were the compressive strength, the internal relative humidity (IRH), and autogenous shrinkage of AAS mortars incorporating different dosages of SAPs. Test results showed that as the dosage of SAPs increased, the reduction of IRH owing to self-desiccation and autogenous shrinkage both decreased, indicating that the SAPs can be effectively used as internal curing agents. The resulting modeling of the internal curing zone is expected to be useful in determining the appropriate dosage of SAPs in AAS mortars.