Cavity contraction solution in a non-linear elastic drained material

This research provides a closed-form solution for small-strain cavity contraction in a stiff cohesive frictional material, forming the basis for modelling of the unloading branch of a pressuremeter test in sands. The strength is defined using a Mohr–Coulomb yield criterion surface while Nova’s stress–dilatancy relationship is considered as the flow rule. This solution is adapted for non-linear elasticity using separate hyperbolic stress–strain behaviours for the pre- and post-stress reversal phases to account for the post-stress reversal softening as described by the Bauschinger effect. For self-bored as well as pre-bored pressuremeter tests, the strength parameters obtained from the proposed solution show good agreement with those derived from cavity expansion analysis during the expansion phase of the test.