Generation and prediction of water waves induced by rigid piston-like landslide

Accurate prediction of water waves generated by landslides is of significant importance in the early warning and risk assessment of landslide disasters. And previous studies shown that landslide-induced waves are of various types, which indicates that there are different generation regimes for landslide-induced waves. In the present study, the generation of water waves by a rigid landslide is studied numerically and theoretically. According to the motion characteristics of a landslide, three types of landslide motions, including piston-like, plunger-like, and transition landslide motions, are detected. The performed analyses demonstrate that the solitary-like wave and dissipative transient bore are generated by piston-like landslides. Moreover, nonlinear oscillatory and transition waves are generated by plunger-like and transition landslides, respectively. It is also found that the wave height generated by piston-like landslide depends on the effective velocity of fluid translated by the landslide. For piston-like landslide motion, the correlation between the wave height, wavelength, and the effective velocity of a rigid landslide is established theoretically, and then, it is verified using numerical results. The present study is expected to provide a reference to investigate early warning of landslide-induced waves.