Coupled heat, water and gas flow in deformable porous media

A fully coupled numerical model to simulate the slow transient phenomena involving heat and mass transfer in deforming porous media is developed. It makes use of the modified effective stress concept together with the capillary pressure relationship. The heat transfer through conduction and convection as well as the latent heat transfer (evaporation and/or condensation) is taken into account. The governing equations in terms of displacements, temperature, capillary pressure and gas pressure are coupled non-linear differential equatiosn and are solved by the finite element method. The model is validated with respect to a documented experiment on semisaturated soil behaviour. Two other examples involving subsidence due to pumping from a phreatic aquifer and thermoelastic consolidation of saturated and semisaturated media are also presented.