Simulating waves induced by landslide using coupled smoothed particle hydrodynamics and discrete element method: Evaluating the impact of irregular rock shapes

The morphology of rock plays an important role in the process of landslide-induced wave, yet it is often neglected in current studies. This work aims to fill this gap by investigating the impact of irregular rock shapes on landslide-induced wave generation and propagation via coupling smooth particle fluid dynamics and discrete element method from a multi-scale perspective. Initially, the wave induced by particle column collapse is reproduced and validated against existing results. Subsequently, the influence of rock shapes, particularly the aspect ratio of particles on landslide-induced waves, is analyzed. The findings indicate that spherical particles, due to their low self-locking tendency and simple force chain structure, exhibit higher average velocities and more stable velocity changes during the landslide process. Spherical particles generate larger free surface waves with smoother and more regular waveforms when entering the water. In contrast, irregular polyhedral particles produce multiple secondary wave peaks alongside the main wave. The wave height induced by these particles is negatively correlated with aspect ratio. Specifically, the maximum run-up height of waves generated by elliptical particles with the highest aspect ratio is 11.7% lower than that of spherical particles. This research highlights the influence mechanism of particle morphology on landslide and tsunami dynamics, which provides a theoretical foundation for disaster prediction and assessment.