方向波中での半潜水式海洋構造物の安全性に関する考察

概要

論文の詳細を見る
Newly amended Code of Mobil Offshore Drilling Units doesn't consider the short crested wave effect on the responses in the stability of the structure. Therefore, in this paper, it will be cleared up how the directionality of the wave affects on each mode of the motion. We developed a simulation program in the time domain and a spectral analysis program for the short crested waves. The latter would save large computational efforts. We compared each result of numerical calculations and we found that the spectral analysis can be used to expect the responses of the structures in the short crested waves. And the accuracy of the numerical calculation programs was validated by the corresponding experimental results in the square towing tank which can generate the bi-directional waves. The experiments were carried out for semi-submersible rig model with eight columms and two lower hulls, which was moored horizontally by four soft linear springs. From the numerical and experimental results, we can find that in the short crested waves, the amplitudes of the motions in the principal direction of wave propagation are smaller and the amplitudes of the motions in other directions are larger than those in the long crested waves. Thus we can conclude that the directionality of the wave has an influence on the each mode of motion.
社団法人日本船舶海洋工学会の論文
1991-03-25