ABSTRACT
In geomechanics, instability manifests itself through various deformation modes. For example, a natural slope may undergo large movements as a result of deformations either localizing into shear bands or developing in a diffuse manner throughout the entire mass. In both cases, the problem underlies a material instability phenomenon that originates in the small scale due to the microstructural features of the geomaterial. At such a microscale, mechanisms of energy dissipation and inter-granular force transmission lead to local instabilities that reflect at the macroscopic scale as shear dilatancy, localization of deformations, and liquefaction, among others.
