Influence of water chemical potential on the swelling of water sensitive materials

A coupled formulation based on non-equilibrium thermodynamics is derived to model the behaviour of expansive shales. Darcy’s law is derived from the dissipation process by using standard arguments of non-equilibrium thermodynamics. The chemical potential of water has been included in classical Biot theory. Thus, the swelling effects due to hydration can be analysed. Finally, finite elements are used to solve the governing equations. The numerical results are consistent with swelling stress and strain responses observed experimentally. The deformations due to swelling are shown to be strongly affected by the choice of swelling parameter.