海床波浪响应的积分变换解及其分析应用

考虑土骨架和孔隙水的压缩性,基于平面应变条件下的Biot方程,研究线性波浪荷载作用下海床的动力响应。采用积分变换的方法,推导突加波浪荷载引起的海床中的孔隙水压力、应力和位移解。以北海的波浪和海床特征为参数的算例表明:在进行近海结构物设计时应注意到突加波浪荷载作用下海床的瞬态响应与稳态响应有较大的差别,其最大瞬时液化深度和区域,较稳态响应计算得到的结果要大;对行波和驻波作用下海床响应的主应力旋转进行描述,指出对于有限厚度海床两种波浪响应的应力路径有显著差异;同时研究土性参数对孔压响应的影响。

Analysis on integral transform of the wave-induced response in seabed and its application

The pore fluid as well as the soil skeleton was considered compressible and the flow in the porous seabed was assumed to be governed by Darcy’s law.A plane strain analysis based on the generalized Biot’s equation was utilized to investigate the induced response by linear planar waves propagating over a poro-elastic seabed.By employing an integral transform method,transient solutions for the wave-induced pore water pressure,stresses and displacements were derived in detail.As an illustrative example,the typical seabed formations in the North Sea under attack of design storm waves were analyzed.It was shown that the distinction between the transient and steady response should be taken into account for design of marine structures.Under the transient condition,the seabed was apt to liquefaction.The stress paths of seabed response under two kinds of wave load were described and the results indicated that there was distinct difference between these loci.Additional parametric study about response of pore water pressure was presented.