In this paper, an elastoplastic modeling method is presented for dynamic consolidation of liquefiable seabed around a pipeline subjected to ocean environmental loadings (i.e. wave and current). Special attention is given to the cyclic plasticity modeling of liquefiable marine sediments and the evolving soil-pipeline interactions, in association with the Biot's dynamic consolidation theory. Motivated by the experimental findings, this paper extends a Masing-type model to the liquefaction-induced deformation regime of marine sediments within the cyclic plasticity framework. A novel plastic flow rule is developed to capture the cyclic-shearing-induced volumetric strain and hence exercise direct control over the response pattern of excessive pore water pressure (EPWP). Then, a model calibration procedure is outlined, with respect to cyclic laboratory sample tests under various loading paths. Finally, the combined actions of current on the wave-induced dynamics of liquefiable seabed around a buried pipeline are studied by numerical examples. The results demonstrate that the propagation of ocean current has major consequences for the wave-induced soil-structure interactions such as EPWP response, liquefaction pattern of seabed over the contact areas and uplift of pipeline. The liquefaction triggering of seabed and the consequence for the dynamic response of pipeline in the wave and current environment are also investigated.

在本文中，提出了一种弹塑性建模方法，用于动态加固海洋环境负荷（如波浪和洋流）作用下的可液化海床周围的管道。结合Biot的动态固结理论，对可液化海洋沉积物的循环可塑性模型以及不断发展的土壤-管道相互作用给予了特别的关注。受实验结果的启发，本文在循环可塑性框架内，将Masing型模型扩展到液化引起的海洋沉积物变形机制。开发了一种新颖的塑性流动法则来捕获循环剪切引起的体积应变，从而直接控制过高孔隙水压力（EPWP）的响应模式。然后，概述了模型校准程序，关于在各种加载路径下进行的循环实验室样品测试。最后，通过数值算例研究了电流对地下管道周围可液化海底波诱导动力学的综合作用。结果表明，洋流的传播对波浪引起的土壤-结构相互作用具有重要影响，例如EPWP响应，接触区域海床的液化模式和管道的隆起。还研究了海床的液化触发以及波浪和当前环境下管道动力响应的结果。结果表明，洋流的传播对波浪引起的土壤-结构相互作用具有重要影响，例如EPWP响应，接触区域海床的液化模式和管道的隆起。还研究了海床的液化触发以及波浪和当前环境下管道动力响应的结果。结果表明，洋流的传播对波浪引起的土壤-结构相互作用具有重要影响，例如EPWP响应，接触区域海床的液化模式和管道的隆起。还研究了海床的液化触发以及波浪和当前环境下管道动力响应的结果。