Predicting cement microstructure and mechanical properties in hydrating cement paste with a Phase-Field model

TL;DR

This paper introduces an improved Phase-Field model for simulating cement hydration microstructure evolution, accurately predicting porosity and mechanical properties by integrating thermodynamics and experimental validation.

Contribution

The work presents a revised PF framework with a new free-energy potential and equilibrium constants, enhancing physical consistency and predictive accuracy for cement microstructure and mechanics.

Findings

The PF model reproduces realistic porosity levels and phase boundaries.

Predicted microstructures align closely with experimental observations.

Mechanical properties derived from the model match experimental trends.

Abstract

Predicting the evolving microstructure of hydrating cement is essential for understanding and modeling its mechanical property development. Physics-based continuum approaches offer a rigorous framework for capturing the thermodynamics of dissolution and precipitation processes at the microstructural scale. In this work, we present an adapted Phase-Field (PF) model for cement hydration that resolves key physical inconsistencies in existing PF formulations by introducing a revised free-energy potential and distinct equilibrium constants for clinker dissolution and hydrate precipitation. The resulting PF framework reproduces microstructural evolution, yielding realistic porosity levels and continuous phase boundaries in close agreement with experimental observations. The predicted hydrated microstructures are subsequently used in a computational homogenization scheme to evaluate the elastic response of the material. The PF-derived mechanical properties show good agreement with experimental trends, supporting the ability of the proposed framework to consistently link hydration chemistry, microstructure formation, and the resulting mechanical response.