Risk assessment of slope disasters induced by typhoon-rainfall in the southeast coastal area, China: A case study of the Shiyang north slope

Abstract

In the southeast coastal areas of China, typhoon-rainfall-induced landslide disasters occur frequently during the flood season each year, which poses a great threat to local people's lives and property. The risk assessment of individual slopes is of great importance for geologic disaster management and prevention. We carried out field surveys, engineering geological drilling, and soil mechanics tests on the north slope of Shiyang Town. The slope stability was discussed in combination with the meteorological data under different rainfall conditions. By using the Monte Carlo method the statistical characteristics of the slope safety factor were calculated. Based on the slope failure probability, the vulnerability of the hazard-bearing body was analyzed, and the risk values for buildings and people under different rainfall conditions were quantitatively calculated. The results show that with the increase in rainfall intensity, the probability of landslide increases, and its risk value increases as well. The risk under extremely heavy rain is the highest, with 94 people per year, and the economic risk is 141 million yuan per year. The research results are a useful guideline for the prevention and control of this type of landslide in the southeast coastal area.

Keywords

• slope
• risk assessment
• vulnerability
• stability
• typhoon-rainfall