Experimental Research On Impulse Wave Generated By Subaerial Landslide And Related Numerical Simulation

Landslide generated impulse wave issues happened frequently in recent years,severe damage which caused cannot be neglected.In order to study impulse wave formation and propagation process,a wave flume model and a complex river channel model had been established,both of which used solid blocks as landslide material.Impulse wave type in above two model experiments was respectively analyzed by wave parameter,method proposed by previous researcher and wavelet analysis.The results indicated that impulse wave belonged to stokes wave theory category.Wave energy spectrum was obtained by wavelet analysis.As for impulse wave in wave flume model,it was detected that low frequency components propagated faster than high frequency components which showed frequency dispersion characteristics of impulse wave.Incident wave and reflected wave could be clearly distinguished through wave energy density versus time curve.As for impulse wave in river channel model,only first wave crest of wave energy density versus time curve could be identified as incident wave.Due to effect of bank slope topography,how subsequent several small wave crests formed was difficult to be determined.Based on impulse wave data and multiple regression method,as for wave flume model,prediction formulas regarding maximum wave crest and first wave height decay were obtained.As for river channel model,prediction formulas regarding maximum wave crest and maximum wave height decay were obtained.And they were compared with corresponding ones proposed by previous researchers.It turned out that prediction formulas we obtained had better fitting effect to experimental data.DualSPHyiscs 4.0 which was based on SPH numerical method had been used to simulate one case of each model experiment.It turned out that simulation results agreed with model experimental results in terms of impulse wave formation process and maximum wave crest amplitude,which reflects that SPH method is practicable in simulating problems concerning impulse wave generated by solid blocks.