固定型4脚構造物の横振動の解析 -海底地層の影響を考慮した海洋構造物の横振動(第3報)- Analysis on Lateral Vibration of Four-leg Structure Supported by Seabed Layer -Analysis of lateral vibration of an offshore structure with consideration of the effect of seabed layer(3rd Report)-
When analyzing the lateral vibration of an offshore structure supported by seabed layer, the effect of this layer must be taken into consideration. In this study, first, the natural frequency of lateral vibration of the offshore structure constructed with four legs and a platform was analyzed theoretically by replacing it with the one-leg structure, the upper end of which was loaded by an axial load corresponding to the equivalent mass of a platform per leg and was constrained to move in the horizontal direction only. Furthermore, the validity of this theory was examined by the model experiment. The main results obtained are as follows：(1) The theoretical natural frequency calculated by the method replacing the 4-leg structure with one-leg structure coincides with the experimental one within the difference of 7 %, and so this method is valid even in case that the effect of seabed layer is taken into consideration.(2) In order to calculate the natural frequencies of practical offshore structures with good accuracy, the leg's axial force due to the weight of the platform must be considered, and the leg's own weight may be neglected in case of a shorter-leg structure (L ≦ 75 m in this study) but must be taken into account in case of a longer-leg one.
- 資源と素材 : 資源・素材学会誌 : journal of the Mining and Materials Processing Institute of Japan
資源と素材 : 資源・素材学会誌 : journal of the Mining and Materials Processing Institute of Japan 114(1), 13-18, 1998-01-25
The Mining and Materials Processing Institute of Japan