On liquid-saturated and empty granular elasto-plastic solid materials accounting for micropolar rotations

摘要

Depending on the boundary-value problem under consideration, granular solid materials (frictional materials), as for instance soil or concrete, exhibit more or less a strong tendency towards localization. When localization occurs, e.g. initiated by a singularity in the outer boundary conditions, the plastic deformations concentrate in small bands of finite width, so-called shear bands (de Borst, 1991 a; Schrefler et al., 1995). The mechanical reason of this behaviour results from the basic properties of frictional materials, where, in the brittle regime, the plastic dilatation yields local softening effects.