GIS-based probabilistic mapping of landslide hazard using a three-dimensional deterministic model

Abstract

Based on a new Geographic Information Systems (GIS) grid-based three-dimensional (3-D) deterministic model and taking the slope unit as the mapping unit, this study maps landslide hazard using the 3-D safety factor index and failure probability. Assuming the initial slip to be the lower part of an ellipsoid, the 3-D critical slip surface in the 3-D slope stability analysis is located by minimizing the 3-D safety factor using the Monte Carlo random simulation. The failure probability of the landslide is calculated using an approximate method in which the distributions of c, φ and the 3-D safety factor are assumed to be in normal distribution. The method has been applied to a case study on three-dimensionally and probabilistically mapping landslide hazard. © 2004 Kluwer Academic Publishers.