IMPULSE WAVES: EFFECTS OF SLIDE DENSITY

摘要

The characteristics of impulse waves generated in reservoirs by the impact of landslides or snow avalanches were assessed using 2-D model experimentation. The slide density was considered as the essential parameter governing the decay of propagating wave amplitudes. The maximum amplitude generally increased with slide density. However, it strongly depended on the wave type characterized by the impact Froude number and the slide density. Similarly, the decrease of the amplitude in the propagation direction was strongest for high impact Froude numbers. The slide Froude number is a novel parameter to determine the combined effects of slide density and impact Froude number. The impulse flux transfer from the slide to the water body was described as inherent characteristic governing the wave features. A distinction between unseparated and separated flows in the wave generation area was considered to allow for the classification of impact crater types. Their strong influence on the evolving wave patterns was emphasized considering distinct regimes. Moreover, a slight increase of wave amplitudes for transient bores was observed for slide densities smaller then the water density. The density effect was assessed for slide impact velocities higher than roughly the double celerity of shallow water waves.