Physical experimental study on coastal landslides inducing waves in different directions

Abstract

[Objective] To predict the disaster scope of reservoir landslide-induced surges, the generation of initial maximum wave amplitude, and the propagation attenuation patterns accurately, thereby enhancing the prevention and control capabilities of surge disasters in mountainous river channels, [Methods]based on mountainous river channel characteristics, three-dimensional physical model experiments for block and granular landslide surges were designed. Through orthogonal experiments and multivariate nonlinear regression analysis, empirical formulas for the initial maximum wave amplitude in the sliding direction and upstream/downstream directions, as well as a propagation attenuation model, were developed. The model accuracy was validated using typical cases such as the Xintan landslide, Tangyanguang landslide, Qianjiangping landslide, and Gongjiafang landslide. [Results] The geometric characteristics of sliding bodies(relative thickness power exponent: 0.94) most significantly influenced the initial maximum wave amplitude of block landslides, while the Froude number(power exponent: 0.83) dominated granular landslide surges. The attenuation rate of maximum wave amplitude decreased exponentially with propagation distance, with the Froude number(power exponent: 0.34) playing a critical role. The model achieved a prediction error of <20% in low-speed scenarios(<30 m/s) and wide river channels, significantly outperforming traditional method, though errors increased to 29% in narrow channels. [Conclusion] The proposed model effectively predicts multidirectional initial surge characteristics, providing theoretical support for refined early warning of reservoir landslide surges in mountainous areas. Future work should integrate numerical simulations to optimize applicability in complex terrains.

Keywords

landslide / landslide surge / physical model experiment / initial maximum wave amplitude / maximum wave amplitude attenuation