Waves generated by subaerial slides with various porosities

Waves generated by subaerial slides were investigated experimentally in a two-dimensional wave tank. Slide volume, initial position, slope angle and equilibrium water depth were kept constant while the slide material was varied. Five different slide types were employed, one block slide and four granular slides with grain diameter ranging from 3 mm to 25 mm. The slides were accelerated by gravity, with different impact velocities and Froude numbers varying from 0.34 to 0.93. Amplitudes of the generated waves were measured with non-intrusive acoustic wave gauges while the slide position during rundown was recorded with a high speed video camera. Empirical functions for prediction of maximum amplitudes that have been reported in the literature were employed for comparison with the generated waves. Differences between predictions based on the empirical functions and experimental results were discussed together with possible effects of permeability.