Mohr-Coulomb criteria

The Mohr-Coulomb criterion is a way to predict when soil or rock will fail or slide under stress. It considers how the material's strength depends on the combination of shear stress (sliding force) and normal stress (force pressing perpendicular). Essentially, failure occurs when the shear stress exceeds a certain limit set by the material's cohesion (stickiness) and internal friction (resistance to sliding). This criterion helps engineers assess stability of slopes, foundations, and retaining walls, ensuring structures are designed to prevent landslides or collapses by understanding when materials are likely to fail under given forces.