ABSTRACT

To effectively avoid or reduce precipitation-related disasters, an appropriate assessment of landslide potential and an early warning system are required. External precipitation is the main key to changing slope stability. This study used the Baoshutang site as an example, geological drilling and hydrologic monitoring data were collected to develop an analytical model, then using the two-dimensional rainfall infiltration-seepage-slope stability analysis model to perform the landslide assessment. In the model, precipitation conditions such as the various rain patterns are used to explore the relationship between precipitation characteristics and slope stability. Based on the above results, this study takes the 72-hour cumulative precipitation as the early warning indicator. After a comprehensive review of the various precipitation patterns and response times, presents the warning value and action value of the Baoshutang site. Based on observations of the Baoshutang slip caused by Typhoon NESAT in 2022, it can see that the alarm threshold developed in this study is useful and has an important reference value. The contribution of this study is to propose early warning indicators that can comprehensively consider precipitation patterns and response time. The model was then employed to determine the alarm thresholds and related emergency actions for other selected slopes in Taipei city.

Keywords: Warning system, Alarm threshold, Slope stability, Numerical simulation, Baoshutang site.