Finite element formulation of unsaturated soil and its application on bearing capacity problems

摘要

This paper presents a finite element formulation and governing equations for fully coupled analysis of unsaturated soil. The spatial and temporal discretization of the governing equations is achieved using the Galerkin method and the backward interpolation scheme, respectively. These equations are implemented into a general finite element program. A series of numerical analyses are carried out to simulate laboratory tests on samples of unsaturated soil and to demonstrate the accuracy of the proposed model. The numerical results are compared with experimental data from the literature. The capability of the proposed model is demonstrated by a series of analyses of footings on saturated and unsaturated soil medium. It is shown that suction developed in unsaturated soil has a direct impact on the bearing capacity of foundations.