Numerical Simulation Study on Dominant Factors of Surge Hazards in Semi-Submerged Landslides

Landslide-generated surge waves are significant natural hazards, posing severe risks to engineering safety. Despite extensive research on the dynamics of landslide-generated waves, studies analyzing controlling factors and their mechanisms remain limited, leaving key influencing processes inadequately understood. This study utilizes computational fluid dynamics (CFD) to perform a numerical simulation of a semi-submerged landslide in a hydropower station reservoir area. The research systematically investigated the effects of key variables, including slide volume, velocity, centroid height, and water depth, on the behavior of semi-submerged landslide-generated surge waves. Results demonstrate a positive correlation of slide volume, velocity, and centroid height with the initial wave height and run-up on the opposing shoreline. However, the impact of water depth reveals a more complex pattern, exhibiting distinct surge characteristics in the near-field and far-field zones. Via correlation and sensitivity analyses, this study elucidated the relationships between these factors and surge dynamics, identifying the primary factors influencing the size of the semi-submerged landslide-generated surge. The findings provide critical insights for predicting and mitigating surge disasters, offering both theoretical foundations and practical application value for landslide disaster prevention and management.