The quasi-static finite cavity expansion in a non-standard elasto-plastic medium

A unified approach is presented for the analysis of the finite static expansion of a spherical or cylindrical cavity in an indefinite elastic-perfectly plastic medium. Mohr-Coulomb yield criterion is adopted with an arbitrary degree of non-associativity of the volumetric dilatational component of the plastic flow. This idealization makes the present analysis particularly appropriate for rock-like materials. The general solution obtained requires a numerical integration over the plastic zone. Some numerical examples, referring to both the spherical and the cylindrical cavity emphasize the determining role of the elastic deformations in the plastic region.