Surface area and size distribution of cement particles in hydrating paste as indicators for the conceptualization of a cement paste representative volume element

The conceptualization of a representative volume element (RVE) hardened cement paste for numerical homogenization mechanical problems rests on identifying the largest discernible microstructural feature, i.e. unreacted grains. While particle size distribution (PSD) anhydrous is well-controlled production parameter, evolution grain throughout hydration remained unresolved. This study analyzes digitized 3D microstructures obtained from X-ray micro-computed tomography, coupled with CEMHYD3D model, and segmented by image-processing tools, to obtain full PSD specific surface area evolutions grains hydration. Results provided indicate in range 30−40μm regardless elapsed, implying RVE should amount 150−200μm realistically represent shape self-similar two distinctive regimes were identified, differing dissolution rate decrease, correlating calcium sulfate reactivity peak. Both measures provide easily accessible features that may be used constructing artificial RVEs micromechanical models related simulations, resting experimental data.