Elucidation on alkali activation of slag with various solid-to-liquid ratios via heat evolution

This research intends to evaluate alkali activation of slag through heat evolution for emphasizing the potential of ambient curing. The heat evolution and cumulative heat evolved acquired were used to further investigate the nucleation and growth mechanisms by using the Johnson Mehl Avrami Kolmogrov model. Increasing the solid-to-liquid ratio resulted in significant changes to the peaks intensity of heat evolution and a decrease in total cumulative heat evolved. Meanwhile, it was found that the nucleation mechanism and growth is driven by instantaneous heterogeneous nucleation with rod-like growth. Furthermore, the lowest heat evolved (238.72 J/g) with the highest growth rate was discovered to produce superior compressive strength properties (51.667 MPa) as well as densified morphology and fewer in microcracks creation compared to the highest total heat evolved (346.92 J/g). The elemental distribution of alkali-activated slag with the least cumulative heat evolved also demonstrated a homogeneous distribution of important elements including silicon, aluminum, and calcium following alkali activation.