Geographic Information Systems-Based Three-Dimensional Critical Slope Stability Analysis and Landslide Hazard Assessment

In this paper, by combining the geographic information systems ~GIS! spatial analysis function and a hydrologic analysis and modeling tool with a column-based three-dimensional ~3D! slope stability analysis model, a new GIS grid-based 3D deterministic model has been developed for slope stability analysis. Assuming the initial slip as the lower half of an ellipsoid, the identification of the 3D critical slip surface in the 3D slope stability analysis is performed by means of a minimization of the 3D safety factor using Monte Carlo random simulation. By using this hydrologic analysis and modeling tool, dividing the whole study area into slope units, and taking each slope unit as a study object, the minimum 3D safety factor for each slope unit can be obtained, and the landslide hazard can then be mapped for the whole study area. DOI: 10.1061/~ASCE!1090-0241~2003!129:12~1109! CE Database subject headings: Geographic information systems; Slope stability; Monte Carlo method; Three-dimensional analysis;