Development of Physical Vulnerability Curve based on Debris Flow Events

In recent years, owing to climate change various slope disasters are rising. Debris flow causes large damage to human life and social infrastructure. Generally, the vulnerability assessment of slope disasters is carried out using vulnerability curve, which consists of hazard intensity and damage index. A vulnerability curve needs to be highly reliable. In this study, GIS-based topographical characteristics and the information about 27 debris flow events that occurred between 2011 and 2020 were collected and analyzed. The hazard intensity of the debris flow events was evaluated considering entrainment of soils and buildings. Two types of buildings, non-reinforced concrete structure (non-RC) and reinforced concrete structure (RC frame) were classified into four types of vulnerability indices (slight, moderate, extensive, and complete) based on the degree of damage to the building. The relationship between the hazard intensity and the degree of damage to the building was studied through nonlinear regression analysis to derive a vulnerability curve according to the hazard intensity. The proposed vulnerability curve can be used as fundamental data for the vulnerability assessment of landslide disasters.