An efficient and accurate cement hydration model and its application in multi-scale simulation

Multi-scale simulation is an effective approach to investigating the influence of the cement hydration process on the microstructure and macroscopic mechanical properties of concrete. However, the computational efficiency restricts its practical application in engineering. In this study, we establish an effective and accurate cement hydration model by proposing the "centripetal displacement method" for efficient placement of cement particles and the "extreme contact positioning method" for particle contact determination. By combining the cohesion model, we obtain the mechanical properties of cement paste at different stages of hydration. The simulation results of the cement hydration model and the mechanical properties, including the degree of hydration, elastic modulus, compressive strength, and tensile strength, exhibit good agreement with the experimental results for water-to-cement ratio ranging from 0.3 to 0.5. Based on the proposed model, the effects of the water-to-cement ratio and hydration age on the degree of hydration, microstructure, and mechanical properties of cement paste,motar and concrete are analyzed.