Computational modelling of steady crack extension in poroelastic media

Abstract

The steady state constant velocity crack extension in poroelastic media is examined for plane strain problems. The finite element formulation of the governing equations for steady crack extension in poroelastic media is developed using a Galerkin technique. The resulting system of non-symmetric coupled matrix equations depends on the propagation velocity at the crack tip. The computational scheme accounts for the stress singularity in the effective stress field at the crack tip. The numerical procedure is verified by comparison with analytical solutions for the pore pressure and displacement fields at the crack tip. The computational procedure is utilized to examine the plane strain problem related to the steady growth of a crack in a poroelastic medium due to its wedging by a rigid smooth indentor. It is shown that the computational methodology can also be applied to examine the penetration of an axisymmetric rigid smooth shell through a saturated geomaterial.