Mohr-Coulomb Failure Criterion Expressed in Terms of Stress Invariants

Abstract

A polynomial expression for the Mohr-Coulomb criterion for failure of brittle or frictional materials in terms of stress invariants is derived. The form of the polynomial expression corresponds to the pyramidal shape of the failure surface in principal stress space. The pressure-sensitive character of the failure of a Mohr-Coulomb material is indicated by a linear influence of the first stress invariant I1 in the polynomial expression.