DEVELOPMENT OF A NON-EXPERT TOOL FOR SITE-SPECIFIC EVALUATION OF LANDSLIDE SUSCEPTIBILITY

Abstract

The development of simplified procedure for evaluating susceptibility of slope to rainfall induced, shallow-depth landslides is presented. The procedure is based on the concept that for extended slopes, the shear strength of the slope material should be greater than the applied load on the slope. The concept is extended to include all types of slope materials including rocks and intermediate geomaterials by developing an empirical shear strength rating system. The proposed system does not require expensive and sophisticated laboratory or in situ field tests and can be performed using improvised tools for estimating slope angle and material strength. This approach makes it suitable for preliminary landslide susceptibility screening by non-experts. A system of empirical weighting factors to take into consideration the effects of vegetation, prior slope failures and ground deformation, land use, drainage and artesian flow are presented. Comparison of the proposed procedure with existing procedures for estimating landslide susceptibility shows good agreement in results.

Keywords: Landslide, slope stability, risk rating, land use planning