Finite element analysis of strain localization in multiphase materials

Finite element analysis of strain localization in multiphase materials is presented. The multiphase material is modelled as a deforming porous continuum where heat, water and gas flow are taken into account. The independent variables are the solid displacements, the capillary and the gas pressure and the temperature. The modified effective stress state is limited by the Drucker-Prager yield surface. Small strains and quasi-static loading conditions are assumed. Numerical results of strain localization in globally undrained samples of dense sand are presented. A biaxial compression test is simulated assuming plane strain condition during the computations. Vapour pressure below the saturation water pressure (cavitation) develops at localization in case of dense sands, as experimentally observed.