A thermo-hydro-mechanical model of unsaturated soils based on bounding surface plasticity

This paper presents a thermo-hydro-mechanical model of unsaturated soils based on effective stress concept and bounding surface plasticity. It is formulated in terms of effective saturation Se and temperature T unlike existing THM models, which use the suction and temperature to predict the behavior of unsaturated soils. An isotropic yield limit is defined in a 3D space p′-Se-T and subsequently generalized to the triaxial stress space. Regarding the hydraulic component, the non-isothermal water retention curves of deformable soils are combined with the present model. However, the part treating the flow of water and temperature is not covered. Finally, the proposed formulations are supported by comparisons with existing experimental results under isotopic and oedometric paths.