Topology optimization of jack-up offshore platform leg structure

Jack-up platforms are commonly found in the costal or offshore environment for offshore oil and gas recovering. Pile legs are the main component of jack-up platform, which support the whole platform and suffer from the ocean environment load. Topology optimization method is proposed in this article to find an optimized shape for the leg by maximizing its structural stiffness, with the purpose of providing enough resistance for extreme environment load. The whole design space is chosen as design variables, and the maximum stiffness is selected as the optimum objective, with the volume and displacement constrained. An innovative leg structure is generated with lighter weight. Finally, the static and transient dynamic characteristics of the optimized structure leg are analyzed, compared with the original one. It is found that the optimization results not only produce better material distribution with less mass, but also enhance the stiffness and strength requirements of leg structure under the extreme environment load.