Landslide-generated impulse waves in deep V channel: Runup and near field characteristics

摘要

Landslide induced impulse wave is a crucial risk for habitation and facility along mountain rivers. "Deep V" shape channels, which are characterized by their deep valleys and steep shores, are very common in mountain rivers. And due to the channels' constraining on wave evolvement, landslide-generated-impulse-waves (LGIW) in "deep V" are very different from the well studied typical three dimensional and two dimensional situations. Focusing on this problem, a direct simulation based on N-S equation is carried out to study the evolving of LGIW in "deep V" channels. And then a series of numerical studies are carried out to investigate the mechanics in this problem. SPH (Smoothed Particle Hydrodynamics) method is used to simulate the whole process of fluid-solid interaction, including the processes of wave-generation, wave-propagation and wave-run-up. LGIW in a deep V channel are found having their special characteristics. They are always undeveloped before run-up at the opposite shore and their generation process and propagation are strongly influenced by both shores.