Point safety factor method for stability analysis of landslide

A 3-D model for numerical calculation of landslide is proposed; and a high-precision eight-node hexahedron element is used to build the finite element grid of slip layer. The slip layer material is simulated by an ideal elastoplastic model based on the Mohr-Coulomb criterion. Three-dimensional stress state and slide direction of the slip layer zone are obtained by numerical computation. So based on the analysis of the three-dimensional stress state of the slip layer zone, a point safety factor as the ratio of the shear strength of the slip zone to the shear stress parallel to the gliding direction is defined; and the safety factor of the landslide as the weighted average value of the zone point safety factor with its zone is defined. The sliding mechanism is studied through zone point safety factor; and landslide stability can be evaluated through the safety factor. The case studies show that the calculated results are consistent with the actual cases.