Performance Validation of Three-Dimensinonal Limit Equilibrium Method for Shallow Landslides Over a Wide Area

Abstract Slope stability analysis based on the limit equilibrium theory has been widely employed in practice. However, the application of the three-dimensional (3D) limit equilibrium method (LEM) for multiple slopes over a large area has not been extensively discussed. In this study, a 3D LEMs-based slope stability analysis was conducted over a large area with actual terrain data under the conditions of shallow failures that occur during heavy rainfall events. The results confirmed that the three different methods have similar trends in receiver operating characteristic (ROC) curves though each evaluated factor of safety is different. In other words, under the conditions of shallow landslides, the Hovland method, which has the lowest computational cost among 3D LEMs, can produce results comparable to those of more advanced methods only by changing the threshold of the factor of safety.