Analysis of wave-induced dynamic response of silty seabed in Yellow River delta

Based on the dynamic consolidation theory of saturated soil and the dynamic constitutive model Pastor-Zienkiewicz Ⅲ,the wave-induced dynamic response of the silty seabed in the Yellow River delta is examined.Liquefaction potential is estimated using a total excess pore pressure criterion.The liquefaction depth calculated is compared with the site observed data at last.Results indicate that the wave-induced excess pore pressure contains two parts: the transient and the residual one.A quicker reduction with depth of the transient pore pressure and a more significant accumulation of the residual pore pressure in the surface layer tend to happen in the seabed that with a surface hard layer rather than a homogeneity one.Under different wave conditions,the value and the variation trend of the transient pore pressure are similar,while distinct differences are found in the residual pore pressure.Under the annual mean wave condition,liquefaction is impossible to happen.While liquefaction would occur under the 5 and 50 years once wave conditions,a greater liquefaction possibility and a bigger liquefaction depth tend to occur while the three-dimensional effect and a surface hard layer of the seabed are considered,the biggest liquefaction depth is within 2-3 meters under the seabed surface.The calculated liquefaction depth is in good agreement with the depth of the submarine disastrous landforms in the Yellow River delta.It is indicated that the method is effective and reasonable.