Two cases of post-limit deformation of rock mass surrounding underground opening

Abstract

Abstract The authors analyze stress state of rock mass around an underground opening in two cases of post-limit plane-strain deformation: when the modulus of compression is much higher than the modulus of post-limit deformation and when the modulus of post-limit deformation is much higher than the modulus of compression. In the first case, the damage zone sizes are obtained depending ultimate elastic strains and strength of rocks. In the second case, the solution in the rock damage zone differs from the traditional elastoplastic solutions by the increase in the maximum shear strength with distance from the boundary of underground opening.