Wave-induced dynamic response of a layered poroelastic seabed around an offshore pipeline

The main objective of this paper is to investigate the wave-induced dynamic response of seabed around a pipeline in a multi-layered porous seabed. Biot's poro-elastic theory is employed to describe the phenomenon of wave-seabed-pipeline interaction in a layered porous seabed. To explore the mechanism of the pipeline instability, the partly dynamic model, u-p model is adopted, where the soil displacement (u) and the pore pressure (p) are the primary variables and it is capable of considering the acceleration of soil skeleton. A parametric study is carried out to examine the influences of various representative seabed and wave parameters. The influence of pipeline buried depth on seabed response is also investigated. The results show that the pore pressure decreases when permeability decreases. The pore pressure concentration reduces as the buried depth e increases, while the vertical stress on the pipeline surface increases as the buried depth increases.