THMC constitutive model for membrane geomaterials based on Mixture Coupling Theory

Modelling of coupled thermal (T), hydro (H), mechanical (M) and chemical (C) processes in geomaterials has attracted attention the past decades due to many significant contemporary engineering applications such as nuclear waste disposal, carbon capture storage etc. However, very-low permeability membrane geomaterials, couplings between osmosis their consequent influence on temperature, water transport deformation remain a long-lasting challenge gap geomechanics geochemistry. This paper extends Mixture Coupling Theory by bridging chemical-thermal field based non-equilibrium thermodynamics, develops new constitutive THMC fully-coupled model incorporating interactions osmosis. Classic Darcy's law been fundamentally extended with major driving force diffusion process. A simple numerical simulation used for demonstration purpose illustrated that will significantly change flow directions, consequently influencing saturation variation deformation.