Establishment of dynamic model of a flow-like landslide-induced surge

Landslide-induced surge is a kind of secondary disasters triggered by waterside landslides. Generally,the endangering range in a landslide-induced surge far exceeds the motion area of the landslide,and accurately predicting spatial evolution of landslide-induced surge is of significant importance for disaster prevention. However,the existing models usually simplify landslides as rigid bodies,which is obviously against the fact that many landslides propagate in a flow-like way. Therefore,a numerical model was put forward in this paper to provide more reliable prediction results for landslide-induced surges. By treating slip masses as flow-like materials,the governing equations of landslide-water coupling motion were derived. Next,the governing equations were solved by the finite difference method,and the dynamic model that can simulate the evolutionary process of flow-like landslide-induced surge was established. Finally,the evolutionary process of Gongjiafang landslide located at the Three Gorges of the Yangtze River was simulated by the model and the simulated maximum wave heights in the longitudinal section (i.e.,the flow direction) of the river were compared with the measured data. Results show that the maximum wave height in this section appears in the main sliding direction of the landslide,and the maximum wave heights on both two sides decrease quickly. The simulated results agree well with the measured values. The established model can provide more adequate prediction of the influence range of landslide-induced surge.