Localization Analysis of a Fluid Saturated Elastoplastic Porous Medium Using Regularized Discontinuities

In the present paper we analyse the conditions for band-shaped localization to occur in the hydro- mechanically coupled problem. The governing continuum equations are based on the porous media theory applied to an elastic–plastic solid (skeleton) at small deformations. In the localization analysis, the concept of regularized discontinuity is extensively used at the application to the conservation laws of momentum and mass. As a result, we obtain a coupled localization condition, where the situation of partly drained conditions is discussed and compared to the two extreme cases of fully drained and undrained situations. A simple numerical experiment for a 1D problem is carried out using an interface FE-formulation. Copyright © 2000 John Wiley & Sons, Ltd.

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