Cavity expansion analysis in elastic – brittle plastic rock mass

Abstract

A comprehensive approach is presented for the analyses of both cylindrical and spherical cavity expansion in an infinite elastic – brittle plastic rock mass. The rock mass obeys the nonlinear generalized “Hoek – Brown” (H-B) failure criterion which is expressed in a scaled form. A plastic flow rule characterized by a constant dilatancy angle is adopted. Closed-form solutions are presented for the extent of the plastic region and the distribution of radial and circumferential stresses. For the displacement field, solutions in the plastic region are developed based on small strain theory. Finally, the solutions are validated using the finite element method