A RESPONSE REDUCTION METHOD OF LARGE FLOATING STRUCTURES IN WAVES

摘要

Large floating structures are intended to be among alternatives for ocean space utilization in deeper coastal area. It has been reported that elastic response is predominant over rigid motions due to their large dimensions with comparatively small bending rigidities. The elastic response must be decreased in order for the enhancement of the rate of operation and the applicability to severer sea area. L-shape attachment structure which is attached to the weather side of the floating structures is especially investigated for this purpose here. First, the attachment structure is experimentally shown to be effective from the viewpoint of vertical response. Numerical calculations are also conducted by use of rigorous numerical method proposed by one of the present authors. It is shown that the numerical results have a good accordance with the experimental results. Further numerical studies clarified that hydrodynamic force cancellation effects plays an important roll in reducing the response.