Slope failure risk assessment considering climate change using analytical hierarchical process: a case study in Singapore

• Main Author: Lam, Kenneth Jia Hui
• Other Authors: Tiong Lee Kong, Robert
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2023
• Subjects: Engineering::Civil engineering
• Online Access: https://hdl.handle.net/10356/168248
• Institution: Nanyang Technological University

Numerous scientific pieces of evidence have given credence to the true existence and deleterious impacts of climate change. One aspect of climate change is the variations in rainfall patterns, whose possible disastrous consequence of this change is the occurrence of rainfall-induced slope failures. Singapore experiences several major and minor slope failures during December and January when the island experiences above average monthly rainfalls. Slope failures varied with respect to slope geometry, soil type, and rainfall intensity. To accurately evaluate the slope failure risk, it is necessary to fuse all the related information contributing to the slope stability. In this study, the Analytical Hierarchy Process (AHP) method is used to produce an assessment model to evaluate the slope failure risk and the climate change impacts on such risk. To be specific, an index system incorporating eight influential factors based on hazard, exposure, and vulnerability is first constructed. Subsequently, AHP is implemented to generate the weightage for each factor, and the final failure risk value is obtained by summing up the product of the weightage and Normalized value of each factor. To investigate the climate change impacts on slope failure risk, the rainfall factor value is adjusted in a wide range, and the sensitivity of the risk value to the rainfall value is studied. To verify the applicability and effectiveness of the AHP-based approach, two slopes in Singapore are used for the case study. It is concluded that the AHP-based approach is a powerful tool to perceive slope failure risk and evaluate the climate change impacts on slope stability.