Assessment of the physical vulnerability of buildings affected by slow-moving landslides

Abstract. Physical vulnerability is a difficult fundamental issue in the risk assessment of slow-moving landslides. We aim to develop a method to analyze the physical vulnerability of buildings affected by slow-moving landslides. We calculate the landslide residual force on the buildings' foundation and the landslide safety factor where the buildings are located using the GEOSTUDIO code and landslide residual thrust method. Further, using Timoshenko's deep beam theory, we analyze the physical response of buildings to understand potential inclination. By applying the modified Weibull function, we fit the physical vulnerability function based on the relation between damage degree and landslide intensity. We simulate three rainfall scenarios by employing the Pearson type III distribution model to evaluate changes in the landslide's residual thrust and corresponding buildings' damage degree. To obtain the contributions of the buildings' characteristics to physical vulnerability, we conduct sensitivity analysis, demonstrating that the building length, foundation depth, and building width are the most critical factors. Two physical vulnerability curve sets are separately generated for four building lengths and five building foundation depths. The proposed method can be applied to establish the physical vulnerability of landslides. The established physical vulnerability curves are used for the quantitative risk assessment of slow-moving landslides.