Microstructural effects on strain localization in a multiscale model for hydro-mechanical coupling

Abstract

The formulation and implementation of a double-scale finite element model for hydro-mechanical coupling in the framework of the finite element squared method has allowed studying macroscale boundary value problems in a poromechanical continuum. The macroscale constitutive relations are directly derived from the micromechanical interaction between fluid and solid microstructure, captured in representative elementary volumes. The application of this model in the simulation of a biaxial test and a gallery excavation problem is presented here to give examples of the model in strain localization problems. While using simple micromechanical models, the results demonstrate the ability of the model to provide complex macroscale material behaviour, that controls the initiation and development of the strain localization.