Seabed-pipe Interaction for Deepwater Applications

The proposed research aims to investigate the response of a pipe section shallowly-embedded in clayey seabed under combined horizontal and vertical loading. Physical and numerical modelling will be carried out in parallel, and the results will be used to develop improved models which are suitable for application to a structural analysis of an on-bottom pipeline or a steel catenary riser (SCR), allowing more economic and safe design of deep-water facilities than is possible using current simple models for pipe-soil response. Physical modelling will be conducted at half scale in a purpose-built plane strain model chamber. The failure mechanisms of a shallowly embedded pipe section undergoing lateral motion will be examined through a transparent window. Digital image analysis technique. Particle Image Velocimetry (PIV) and photogrammetry, developed in Cambridge University is an ideal tool to offer insights in the kinematics involved. Artificial and natural seabed clay will be used in the investigation. As a complementary component, finite element simulations will be carried out to assess the soil-pipe interaction at large deformation. Remeshing technique will be employed which allows the entire process from pipe (or riser) placement to large lateral deformation to be simulated.