Numerical study on seafloor liquefaction around a trenched pipeline in random sea conditions

Abstract

In this paper, unlike most previous investigations have been limited to the purely wave conditions or combined wave and current condition, a numerical model for random wave-induced seabed response around a pipeline in a trenched layer is established. Based on Longuet-Higgins random wave theory and finite volume method. The seabed is treated as a poro-elastic medium and characterized by Biots consolidation equations (QS model). The B-M spectrum is considered in the new model for the simulation of random waves. Numerical examples demonstrate the significant influence of irregularity of random waves on the wave-induced pore-water pressures and the resultant seabed liquefaction around the trenched pipeline, which is different from the cases under the regular waves or waves plus ocean current loading.