Air granulated basic Oxygen furnace (BOF) slag application as a binder: Effect on strength, volumetric stability, hydration study, and environmental risk

This study evaluates the air granulated BOF slag potential as a cementitious material by comparing the granulated and conventionally cooled slags. The mechanical performance of the cement-slag composites is correlated with the hydration behaviour through thermal, mineralogical, and microstructural analysis. The findings show that the granulation improved the grindability, reactivity, and compressive strength till 28 days. The ∼5% slag can be substituted as a binder and ∼35% as an inert filler. The performance decline upon 20–50% replacements is attributed to the absence of brownmillerite reactivity. Overall, the granulation did not improve the cement-slag composite performance significantly till 90 days.