The endothermic rate of fine BOF slag was smaller than those of cement. For coarse BOF slag, the exothermic rate was much lower than that of fine one. Liu and Wang [17] partially replaced cement in pastes with 20% SS + 20% slag, 22.5% SS + 22.5% slag and 25% SS + 25% slag. The results showed a reduction in the heat of hydration up to 72h with the incorporation of SS coupled with slag. As the cement replacementincreased as the exothermic peak of the composite delayed and the exothermic peak decreased.