Development of shallow seismic landslide potential map based on Newmark’s displacement: the case study of Chi-Chi earthquake, Taiwan

With the development of the geographic information system (GIS), the analysis of regional slope stability under seismic loading has evolved rapidly in recent years. In many studies, the Newmark’s method is used for the computation of displacements triggered by an earthquake on a single slope, while for regional analysis, the infinite slope theory is frequently used due to its simplicity when large amount of computations are required. In this research, the infinite slope theory was examined considering various seismic conditions, material properties, and slope geometry to verify the suitability of the method when applied to regional analysis and development of potential shallow landslide maps. The landslide cases induced by Chi-Chi earthquake in central Taiwan were used in this study for verification. It was found that the infinite slope theory is valid for regional analysis when used with discretion. Based on the calculated Newmark’s displacement and combining the GIS technique, procedures for the potential map development are established in this study.