RESEARCH ON CAPSIZING MECHANISM OF FLOATING STRUCTURES IN COMBINED ENVIRONMENTAL CONDITIONS

复合环境条件下浮式结构倾覆机理研究

• 批准号: 02452185
• 负责人: MAEDA Hisaaki
• 金额: $ 4.1万
• 依托单位: UNIVERSITY OF TOKYO
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1990
• 资助国家: 日本
• 起止时间: 1990 至 1992
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-02452185/
• 关键词: Semi-Submersible; Stability; Safety; Capsizing; Combined Environmental Forces; Life Raft; Wind, Wave, Current; Multi-Directional Waves; セミサブリング

International Maritime Organization (IMO) considered to develop a safety regulation which covers a life raft with sea-anchor, since serious fatality has occured on capsizing of large floating structures or life rafts in combined environmental conditions, such as waves, wind and current. In fact this kind of regulation is discussed without any deep insight of mechanism of capsizing. IMO guarantees the safety of large floating structures considering some margins for reserved buoyancy or taking account of full scale test of life rafts in real severe sea conditions. If the mechanism of capsizing of these floating bodies is made clear, it is possible to evaluate the absolute safety of these floating bodies in severe sea conditions, and we can develop reasonable countermeasures for capsizing of floating bodies.In this project we developed an equation of capsize of floating bodies, and completed the computer code of behavior of floating bodies in time domain in which we take account of mutli-directional waves, line structures such as risers, second order wave excitations and nonlinear hydrodynamic forces derived from separated flow.. Finally we proposed the evaluation method of safety of life raft with sea anchor in which we pointed out the importance of wind lift force that is dominant force for capsizing.

由于大型漂浮结构或救生筏在海浪、风和水流等综合环境条件下倾覆造成严重死亡事故，国际海事组织（IMO）考虑制定一项涵盖海锚救生筏的安全法规。事实上，这种调节是在没有深入了解倾覆机制的情况下讨论的。 IMO保证大型浮动结构的安全，考虑到保留浮力的一些余量或考虑到救生筏在真实恶劣海况下的全尺寸测试。如果弄清楚这些浮体倾覆的机理，就可以评估这些浮体在恶劣海况下的绝对安全性，并制定合理的浮体倾覆对策。在本项目中，我们建立了浮体倾覆方程，并完成了时域浮体行为的计算机代码，其中考虑了多向波浪、线结构等 最后提出了海锚救生筏安全性评价方法，其中指出风升力作为倾覆主导力的重要性。

项目成果

H. Maeda, T. Yamazaki: "Safety Assessment of Offshore Structures" Proceedings of 11th Ocean Engineering Symposium, SOCIETY OF NAVAL ARCHITECTS OF JAPAN. 231-238 (1992)

H. Maeda，T. Yamazaki：“海上结构的安全评估”第 11 届海洋工程研讨会论文集，日本造船学会。

Zhi Yu,H.Maeda: "On the Modeling of a OWC Wave Power System" 関西造船協会講演論文集. 53-54 (1990)

zhi Yu, H.Maeda：“关于 OWC 波浪发电系统的建模”关西造船协会讲座论文集 53-54 (1990)。

宮島 省吾,趙 孝済,前田 久明: "多方向海洋波中の浮体の挙動" 生産研究、東大生研. 44. 421-424 (1992)

Shogo Miyajima、Hyoji Cho、Hisaaki Maeda：“多向海浪中浮体的行为”，东京大学 IIS 生产研究，44. 421-424 (1992)。

前田 久明: "浮遊式海洋構造物の研究の現状(その2)" 生産研究 東大生研. 44. 403-410 (1992)

前田久明：“浮动海洋结构物的研究现状（第 2 部分）”生产研究，东京大学 IIS 44. 403-410（1992）。

H.Maeda,H.J.Jo,S.Miyajima: "EFFECTS OF DIRECTIONAL WAVES ON THE LOW-FREQUENCY MOTIONS OF MOORED FLOATING STRUCTURES" ISOPE'92. 3. 489-495 (1992)

H.Maeda、H.J.Jo、S.Miyajima：“定向波对系泊浮动结构低频运动的影响”ISOPE92。