Influence of Particle Internal Pores on Hydration Kinetics and Microstructure Development in Tricalcium Silicate Hydration

Abstract

The accurate reconstruction of the morphologic organization of reactants would be a crucial aspect in understanding tricalcium silicate (C3S) hydration. However, C3S particles are generally regarded as nonporous solids for simplification in most simulation models. This study aimed to analyze the influence of particle internal pores (PIPs) on hydration kinetics and microstructure development in C3S hydration. The CEMHYD3D model was modified to generate the C3S particles with pores, and its algorithm was accordingly updated. The cases of C3S hydration with various internal pore size distributions (IPSDs) and particle porosities (PPs) were simulated using the modified model. The results indicated that (1) the integral absolute errors for the hydration heat obtained from the simulation considering PIPs decreased by 53.3%, compared with that without considering PIPs; (2) the hydration heat difference between the IPSD categories D and E at 50 h was only 0.5 kJ·kg−1 which accounted for 0.14% of the hydration heat obtained with the IPSD Category E; and (3) for a fixed PP, the dissolution of the C3S particle with more small-sized PIPs would be more isotropic than that with less small-sized PIPs.