Mohr–Coulomb theory

Summary

Mohr–Coulomb theory is a model of failure for soils, rocks and concrete. In these materials the shear strength grows with the compressive stress across the failure plane. A plane fails when its shear stress reaches a cohesion plus a friction term proportional to the normal pressure on it. In terms of Mohr's circle, failure occurs when the largest circle touches a straight line, the failure envelope. It is the basic strength criterion of geotechnical engineering.