Structural Collapse Behavior of Very Large Floating Structures in Waves

波浪中超大型漂浮结构的结构倒塌行为

• 批准号: 13450409
• 负责人: FUJIKUBO Masahiko
• 金额: $ 5.12万
• 依托单位: Hiroshima University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-13450409/
• 关键词: Very Large Floating Structure; Collapse behavior; Wave; Structural safety; Idealized Structural Unit Method; Buckling strength; Ultimate strength; Structural reliability; 波浪荷重; 理想化構想要素法

A method of global collapse analysis of a pontoon type Very Large Floating Structure (VLFS) in waves was developed and applied to the structural safety assessment of a VLFS in extreme waves. The results can be summarized as follows1. As a fundamental tool of the collapse analysis of a VLFS, a computer code for the buckling/plastic collapse analysis of stiffened plates using Idealized Structural Unit Method (ISUM) was developed. The degrees of freedom (d.o.f.s) required in ISUM is much smaller than in Finite Element Analysis (FEA). ISUM results were verified through a comparison with FEA results.2. A computer code for the progressive collapse analysis of a VLFS was developed applying ISUM stiffened plate model. A concept of ISUM super element that can further reduce d.o.f.s to be solved were introduced to enable a global collapse analysis of a VLFS having planar dimensions of thousands of meters.3. In order to examine the fundamental features of dynamic collapse behaviour of a VLFS in waves, a simplified dynamic collapse analysis of a VLFS was performed assuming the deflection expressed by the sum of elastic eigen modes. A tank test for a small-scale model was performed to examine the accuracy of hydroelastic response analysis employed in the project4. A system of global collapse analysis of a pontoon type VLFS in waves was developed combining ISUM and elastic response analysis. The external loads including radiation forces, obtained by the hydroelastic response analysis, are applied quasi statically to ISUM VLFS model mounted on an elastic foundation.5. Applying the developed system, the structural safety of a floating airport model in ultimate strength limit state was assessed. It was found the VLFS under consideration has enough strength reserve beyond the design loads. The structural reliability analysis of a pontoon-type VLFS considering damage to the breakwater was performed also.

提出了一种浮桥型超大型浮体结构在波浪作用下的整体倒塌分析方法，并将其应用于超大型浮体结构在极端波浪作用下的结构安全性评估。结果可以总结如下1。本文开发了一套应用理想结构单元法（ISUM）进行加筋板屈曲/塑性破坏分析的计算机程序，作为VLFS倒塌分析的基本工具。ISUM所需的自由度（d.o.f.s）比有限元分析（FEA）要小得多。通过与有限元分析结果的比较，验证了ISUM的计算结果。应用ISUM加筋板模型，编制了VLFS连续倒塌分析的计算机程序。为了实现平面尺寸为数千米的超大尺度光纤结构的整体崩溃分析，引入了ISUM超单元的概念，进一步减小了需要求解的点距。为了考察VLFS在波浪作用下动力破坏行为的基本特征，假设弹性本态模态之和表示的挠度，对VLFS进行了简化的动力破坏分析。为了检验项目中采用的水弹性响应分析的准确性，进行了小规模模型的水箱试验。结合ISUM和弹性响应分析，建立了浮桥型VLFS在波浪作用下的整体倒塌分析系统。将水弹性响应分析得到的包括辐射力在内的外载荷拟静力作用于弹性地基上的ISUM VLFS模型。应用所开发的系统，对某浮动机场模型在极限强度极限状态下的结构安全性进行了评估。结果表明，所考虑的VLFS在设计载荷之外具有足够的强度储备。并对考虑防波堤损伤的浮桥式VLFS进行了结构可靠性分析。

项目成果

Tao-Yun Xiao: "Fundamental Study on the Collapse Analysis of VLFS in Waves"Proc. of 12th Int Conf Offshore and Polar Engineering. Vol.I. 371-378 (2002)

肖涛云：“波浪中VLFS塌陷分析的基础研究”Proc.

Tao-Yun Xiao: "Fundamental Study on the Collapse Analysis of VLFS in Waves"Proc of 12^<th> Int Conf Offshore and Polar Engineering(ISOPE2002). (発表予定). (2002)

肖涛云：“波浪中VLFS塌陷分析的基础研究”第12届国际海洋与极地工程会议（ISOPE2002）（待提交）。

藤久保昌彦: "防波堤被災を考慮したポンツーン型メガフロートの構造安全性評価に関する研究"日本造船学会論文集. 190. 337-345 (2001)

Masahiko Fujikubo：“考虑防波堤损坏的浮桥型巨型浮体结构安全评估研究”日本造船学会汇刊 190. 337-345 (2001)。

Masahiko Fujikubo: "Collapse Analysis of a Pontoon-Type VLFS in Waves"Proc.of Int.Symposium on Ocean Space Utilization Technology. Vol 1. 197-204 (2003)

Masahiko Fujikubo：“波浪中浮桥型 VLFS 的崩溃分析”海洋空间利用技术国际研讨会论文集。

Masahiko Fujikubo: "Structural Safety Assessment of a Pontoon-Type VLFS Considering Damage to the Breakwater"J.of Marine Science and Technology. Vol.7. 119-127 (2003)

Masahiko Fujikubo：“考虑防波堤损坏的浮桥型VLFS的结构安全评估”海洋科学与技术杂志。