A new three-phase numerical model applied to coupled flow-deformation behaviors of unsaturated porous media

摘要

Coupled flow-deformation behaviors of unsaturated porous media (soils) are analyzed by a newly proposed three-phase numerical model. The proposed model constitutes a new (effective) stress expression, derived by the modern porous media theory, to model the deformation behavior and the generalized Darcy's law, ideal gas law, concept of capillary pressure and relative permeability to model the flow behavior of fluid phases. Due to the complexities to solve the coupled field equations of the proposed model by analytically, numerical methods (finite element method and generalized trapezoidal method) are employed and research computer code is implemented. To validate the proposed model, hypothetical analyses of the fully coupled consolidation of loaded vertical soil column problem is performed and finally, applicability and limitation of the proposed model is demonstrated by a simulation of a flexible footing resting on a three-phase soil foundation problem.