Study On The Landslide Of Gentle-slope Silty Seabed Under Waves

In the gentle-slope silty seabed there are various engineering geological hazards such as collapse pits, slope failure, silt flows, as well as intense human activities such as construction of oil rigs and pipe installation of submarine cables in the Yellow River Delta. Therefore, research in seabed landslide on gentle-slope silty seabed is of great significance in the prevention and control of hazards, and on such basis the research work in this paper is carried out.Seabed of gentle silty slope is specifically investigated in this paper. On the basis of data obtained in submarine geological investigation of superficial collapse pits on gentle-slope seabed, wave-induced landslide of such gentle-slope silty seabed is taken as the study objective, and the silty seabed of the Yellow River Delta is taken as a study case. Research work includes flume experiments, dynamic triaxial experiments, in-situ investigation and measurement or experiments, theoretical analysis and calculation, and summing up of previous research results.In this paper, flume experiments are carried out to observe the sliding course of gentle-slope seabed, which exhibits as local superficial soil body, acted upon by the shearing actions of wave peak and wave trough, sliding downwards to form sheet flow. Dynamic triaxial tests are carried out to stimulate wave actions, results of which show that strength of silty soil is weakened under actions of cyclic loads and as a result of reduction of strength indexes the weakened silty soil tends to slide under the shearing actions of waves; this could reasonably explain the sliding mechanism of gentle-slope silty seabed. Results of in-situ measurement and experiments indicate the distribution discrepancy of engineering geological hazards such as landslide in silty seabed. In theoretical analysis, methods are given to calculate wave-induced landslide of gentle-slope silty seabed, which shows that after strength of silty soil is weakened landslide tends to occur in the gentle-slope seabed of the Delta. On the basis of...