Introducing a New Cement Hydration and Microstructure Model

This paper presents a new cement hydration model to predict the microstructure evolution of hydrating tricalcium silicate (C3S). The model is written in MATLAB and employs the continuum approach and integrated particle kinetic relationships to show the change in C3S and the growth of Calcium Silicate Hydrate (C-S-H) and Calcium Hydroxide (CH) in the pore space over time. Cement hydration is a highly complex process. While hydration models should never completely remove experimental analysis, they are an aid to better understand cement hydration and microstructure development by providing a method to analyse a large number of pastes with different cementitious make-ups in a relatively short time. This model uses spherical particles to represent the C3S with customizable input files such as cumulative weight distributions (CWD), to determine the particle size distributions, PSD), w/c ratio, C3S, C-S-H and CH phase densities, kinetic rates, stiochiometries and enthalpy values. The current study presents simulated microstructures and demonstrates the versatility of the model, while still in the development stage, to simulate cement hydration and microstructure development over 100 days. With further development, it can become a flexible tool for both academia and industry that can easily incorporate the inclusion of supplementary cementitious materials etc.