Current Topics in Non-Elastic Deformation of Geological Materials

Inelastic volume deformation, especially dilatancy, and pressure-sensitive yielding are essential features of plastic deformation in geological materials and these do not permit the use of classical elasto-plastic mathematical models. We will give a qualitative description of the ranges of the non-elastic mechanical response of porous or cracked materials, and will discuss idealized constitutive models, the preference for non-associated flow rules, conditions for the localization of deformation, post-shock effects, and pore-fluid coupling in dilatant strengthening and softening.