Local scour and self-burial of a submarine pipeline on cohesive seabed

摘要

A submarine pipeline on cohesive seabed was investigated using an integrated surveying system, including a dual-frequency side-scan sonar, a high resolution sub-bottom profiler, and a swath sounder system. By analyzing the pipeline field investigation data, the concepts of ‘side scour’ and ‘down scour’ were proposed for the local scour around submarine pipelines in cohesive beds, which probably result from tidal currents and hurricane-induced currents respectively. The submarine pipeline in the deep water regime (with water depth > 37m) possibly buried itself due to hydrodynamic effects, submerged weight and the side scour. The maximum burial depth of the pipeline was the total effects of that caused by gravity and the side scour respectively, while the later effect corresponds well with the maximum side scour depth.