Three‐Dimensional Numerical Investigation of Landslide Generated Impulse Waves: Generation, Propagation and Overtopping

This study presents a three‐dimensional numerical modelling of the process of landslide waves in a reservoir, with particular emphasis on the wave types, their propagation characteristics and the process of dam overtopping. The numerical model is firstly validated by comparing against experimental data of a 1:200 physical model. Subsequently, an in‐depth analysis of the wave types, generation, propagation and the phenomenon of dam overtopping is conducted. It is found that the attenuation of the leading wave crest is substantially influenced by the geometric and bathymetric features of the reservoir. Predictions of the generation and propagation of the leading wave crest by empirical method are compared against the numerical results. While the empirical predictions generally follow the numerical trend for cases within the validated parameter ranges, systematic deviations and significant applicability limitations are also identified. Regarding the process of dam overtopping caused by the impulse waves, it is ascertained that the leading wave contributes little to the total volume of overtopping. Instead, the overtopping is predominately caused by the subsequent waves, primarily due to the multiple scattering of the waves within the reservoir. This finding is of utmost importance for the assessment of disaster risks of landslide generated waves in practical engineering scenarios.