Fluid-structure interaction in dynamic strain localisation of multiphase geomaterials

This paper is devoted to the analysis of the fluid-solid interaction in dynamic strain localisation of initially water saturated porous media. The experimental results show the importance of the fluids phases during localisation of undrained water saturated dense sands. Therefore the use of a multiphase material model is necessary. Such a model is presented in the paper and is used for the numerical analysis of strain localisation phenomena. The important role of the fluids for localisation analysis is demonstrated also by the existence of an internal length scale contained in the model and strongly dependent, among other parameters, on the permeability of the medium