ABSTRACT
Calcium silicate hydrates (C-S-H) and Alkali-SiIlica Reaction (ASR) products exhibit a gel mesostructure in which solid colloidal particles are arranged in the mesoscale forming a phase with mesoporosity. The mesotexture determines the properties of the gel. Modeling the gel scale is challenging since the system sizes required to have a representative volume of the gel can be prohibitive for full atomistic simulations, whereas the approaches based on the continuum mechanics (e.g., homogenization) need to be proven valid at that scale. Coarse-grained (CG) simulations, in which the particles represent chunks of the phase considered interacting via potentials of mean force, enable assessing the gel scale. So far, no study has proposed CG simulations to understand ASR gels’ mesostructuration. CG simulations have been successfully applied to model C-S-H, but to date, the flexibility of the layers has not been taken into account. Here, we deploy CG simulations to study the mesotexture of ASR and C-S-H gels using the effective interactions identified at the molecular scale. In the case of C-S-H, we propose an original strategy to incorporate the flexibility of the layers. The CG simulations provide configurations of gels at various packing densities, and these configurations are used to assess the structural features and properties at the gel scale.
