Quantitative risk assessment and its application for individual landslide disaster based on slope failure probability

Effective risk assessment of potential landslide disasters is crucial for informed decision-making in engineering projects. In practical engineering, the risk assessment of individual landslide disasters still relies mainly on qualitative evaluation methods. The qualitative risk level is obtained through the risk matrix based on danger and loss, which poses problems of multiple and discontinuous risk standards. This makes it difficult to compare and classify risks in actual engineering, and may also lead to errors in risk assessment results, misleading risk management. To address these issues, a probability model is employed to quantitatively describe the stability of landslide disasters, considering the size of losses to the element at risk. A quantified risk index for individual landslide disasters is obtained, introducing the concept of landslide disaster risk surface and risk contour. Corresponding evaluation and calculation software are developed to form a quantified risk assessment method for landslide disasters, eliminating the multiplicity and discontinuity of risk standards brought about by traditional landslide risk matrices. The accuracy of the evaluation is improved. By conducting quantitative risk assessment on six individual landslides in Fengjie County, Chongqing, the correctness and reliability of the quantitative risk assessment method were verified, providing a new approach for landslide disaster risk assessment.