Mathematical model for hydration of cement and formation of the cement microstructure

This paper proposes a new mathematical model, based on the unsteady diffusion theory, for hydration of cement and formation of the microstructure of the hydrated cement. The model concerns particularly with the diffusion of cement elements out of cement particles besides the diffusion of water into cement particles. The proposed model allows the process of cement microstructure formation being quantitatively predicted besides the cement hydration process. In particular, the model successfully describes the effects of specific surface area of cement, water-cement ratio, rate constant, diffusion coefficient and curing temperature on the hydration of the cement as well as on the formation of the microstructure. Numerical simulations, which are shown in this paper, suggest a large applicability of the proposed model to the prediction of the mechanical properties of concrete. In particular, the model enables the theoretical elucidation of the peculiar strength development mechanism of concrete cured under high temperatures.