Optimization of the dynamic response of a semi-submersible type megafloat

In recent years, many researches have been made on the middle-scale floating airport using semi-submersible type megafloat. However, few researches have been done from the viewpoint of the design of elastic response. An elastic response characteristic must be designed under the constraints that the structural response is small enough and the structure is safe. This is a subject to be investigated further. In this paper, in order to find the optimized form of semisubmersible type megafloat, an optimization procedure more efficient than before is proposed. An objective function based on the concept of risk which rationally unifies the structural weight, strength and functionality aspect of the structure such as motion and elastic response is proposed. To reduce heavy burden of calculation, a simplified analysis model with sufficient precision and short calculation time was developed and used for the optimization. The simplified analysis model was developed based on the equation of motion of rectangular plate. Using this model, semisubmersible type megafloat was optimized and new form of semisubmersible type megafloat was obtained.