Dynamic Response Of Elasto-viscoplastic Porous Media On Different Yield Function

The saturated porous media model, which is based on the mixture theory in modern continuum mechanics frame, is very excellent in both mathematics and physics. Nowadays, it has been accepted by more and more people. The finite element numerical analysis is one of the important methods in the dynamic response investigation of fluid saturated porous media model.Firstly the paper has reviewed the developments of fluid saturated porous media model and its numerical analysis methods. Then we suppose that the solid bone is isotropic media ,and the liquid in the cavity is ideal fluid in simulation. The dynamic governing equations can be established through combining the saturated porous media model, which describe the coupling between the distortion and fluid flow. By using the Laplace transform technique, we can acquire the one-dimensional analytical solution of dynamic response for fluid saturated porous media.Furthermore, solid skeleton was viewed as elasto-plastic material and a penalty finite element formulation for dynamic response question of fluid saturated porous media was attained with using Galerkin weighted residual method.The node's degree of freedom and the scale of equation are reduced by use the proportion between the pressure and the penalty parameter to eliminate the pressure in governing equations. Deduces the process of nonlinear iterative solution with the Newmark integration method.and a two-dimensional elastic-plastic dynamic finite element program is obtained.According to the finite element numerical analysis of dynamic response for the liquid-saturated foundation,we can achieve some characteristic of elastic-plastic dynamic response of fluid saturated porous media.At last,based on elasto-plastic saturated porous media model, viscoplasticity was introduced as a general procedure to regularze the elasto-plastic porous solid, and an elasto-viscoplastic saturated porous media model was established.To the further research of dynamic strain localization in fluid-saturated porous media,the implicit/explicit predictor-corrector of Hughes was chose to finite element numerical analysis and a two-dimensional elastic-viscoplastic dynamic finite element program is obtained. Through several numerical examples, the satisfactory results were attained, and we can also acquire some characteristic of elastic-viscoplastic dynamic response of fluid saturated porous media.