Early hydration properties and reaction kinetics of multi-composite cement pastes with supplementary cementitious materials (SCMs)

To simulate the hydration process of multi-composite cement pastes with supplementary cementitious materials (SCMs), this paper investigates the early hydration performance, and reaction kinetics of compound system. Significantly, the exothermic characteristics of binary, ternary and quaternary cement blends with three typical SCMs were experimentally evaluated through isothermal calorimetric test, and the hydration mechanism and kinetics parameters were calculated and analysed quantitatively. A second exothermic peak was observed in the cement blends in various particle size groups, and the hydration heat peak varied amongst different complex conditions. The Krstulovic–Dabic model segmentally described the relationship between the rate and degree of hydration of the fine-grained, coarse-grained, and normal-grained groups. The cumulative heat release simulated by the Knudsen equation was within 10% of the experimental results of 72 h isothermal calorimetric measurements. Hence, isothermal calorimetric, combined with kinetic models, is a valuable method for investigating the hydration kinetics of multi-composite cement blends.