ABSTRACT

Cutting processes that commonly disturb the seabed and have direct implications for the offshore industry are iceberg scour, anchor dragging, trawling and the cutting and ploughing processes associated with the installation of pipelines and cables. The first three processes are out of the control of an engineer and if contact of any of these is made with a pipeline this can cause damage. Pipeline burial to beneath the affected zone is the primary form of mitigation. Ploughing is a more controlled process, which is used during pipeline installation. Both iceberg scour and ploughing processes disturb the mechanical state of the soil as a rigid body penetrates horizontally through the seabed near the surface. These processes are examined in this paper by means of physical modelling.