Analysis of dynamic response characteristics of seabed saturated sediment under different permeability conditions
The pervious conditions of seabed sediments can directly affect their dynamic response characteristics during earthquakes,but most existing theoretical studies directly assume that the bottom of the sediments was an impermeable boundary.Therefore,based on Biot's saturated porous media theory,through the analytical and semi-analytical solutions of the seabed transient response or steady-state response,the influence of the bottom water permeability conditions of the sedimentary layer on its dynamic response characteristics in earthquakes is studied.It is found that under the condition of bottom displacement excitation,fast wave or slow wave will generate the same type of compression wave when passing through the impermeable boundary of the sediment layer,and two types of compression waves will be generated when passing through the completely permeable boundary of the sediment layer.Even under the same excitation conditions,the vibration amplitudes of the two types of compression waves generated in the sediment layers with different permeabilities are significantly different.Permeable conditions at the bottom of the sediment layer also affect the frequency response characteristics of the seabed,and the displacement amplification coefficient of the bottom permeable sediment layer is large at low frequency.On the contrary,at high frequency,the displacement amplification coefficient of the bottom impermeable sediment layer is large.
sea area earthquakedynamic responsepermeable boundary conditionssaturated sedimentary layerdynamic permeability coefficient
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万方数据
维普
