Avoiding jack-up rig foundation failures

A mobile jack-up rig faces a much greater accident exposure than most engineering structures. About one third of the mobile rig accidents are caused by foundation problems. This paper examines the six different types of foundation failure modes and discusses available means for reducing the accidents. Foundation designs, loading conditions, and operational characteristics are examined in the paper. Various geophysical and geotechnical site investigation techniques are described that help reduce the risk of failure. The paper reviews the different analytical procedures that may be used to predict safe foundation performance. The conclusion calls for more open communication between rig manufacturers, operators, and geotechnical engineering service companies.