Numerical investigation of landslide?induced waves: a case study of Wangjiashan landslide in Baihetan Reservoir, China

摘要

Landslide-induced waves often result in severe casualties, economic losses, and even catastrophic consequences, whichare far more destructive than the landslide itself. In this paper, accurate geomorphological and geological characteristics ofthe Wangjiashan landslide in Baihetan Reservoir, southwest China, were obtained through field investigations, and a threedimensionalmodel was built for numerical calculation. Through the time series curve of cumulative deformation, the waterlevel variation of the reservoir was found to be the major factor causing the landslide deformation and eventual failure. Thegeneration and propagation progress of water waves induced by the Wangjiashan landslide was simulated by coupling thegranular flow model and renormalization group turbulence model in FLOW3D. The results show that a large sliding masssilts up the channel, forming a landslide dam with a maximum height of 21.5 m. Nevertheless, it does not block the channeland will not affect standard navigation on account of the wide channel in this area. The maximum run-up wave height ofwaves spreading to the Xiangbiling resettlement area on the opposite bank is 3.7 m. As the resettlement area is only 1.3 kmaway from the landslide, and its elevation is only 2.5 m higher than the normal water level of the reservoir, landslide-inducedwaves should be considered a potential threat. The most vulnerable area affected by landslide-induced waves is about 8 kmlong along the river, where wave run-up heights are more than 1 m. The results in this paper have important reference valuesfor the early warning and prevention of potential disasters caused by landslides and landslide-induced waves.