Study On The Structural Optimization Of Jacket Platform Under The Dynamic Ice Load

Offshore jacket platform is the foundational facility for offshore oil exploiting, and the base for marine producing and living. At present some achievements have been made on the study of offshore jacket platform structure system. But the most of them are the static analysis and safety assessment. In fact, most of the environmental loads are dynamic loads. While those platforms working the glacial areas, like Bohai Bay area, special attention should be given to the dynamic ice load.In this paper, the optimum design model of JZ20-1MUQ jacket platform is established with the dynamic ice-load as the main function load, and the optimization of jacket platform is discussed in two aspects.Based on the unified design variable method, a typical two-truss structure is optimized and compared with the result in references. The result indicates the effectiveness of the algorithm. Then using the unified design variable method, the sizing and shaping optimization of jacket platform is performed. The optimization result of JZ20-1MUQ platform indicates the application value of the algorithm in this section.With the application of Immune genetic algorithm, the jacket platform JZ20-1MUQ is optimized under the dynamic ice-load. During the optimization, the pipe thickness of the jacket platform is defined as the discrete design variables. Satisfactory result is achieved through the optimization.Both work is based on the commercial finite element analysis software ANSYS with its APDL as the programming language, so that the structural analysis and optimization process can be combined in the same working environment.