Establishment of Design Procedure of Semi-submersible Type Very Large Floating Structure

半潜式超大型浮式结构物设计程序的建立

基本信息

批准号：
11450386
负责人：
SUZUKI Hideyuki
金额：
$ 7.87万
依托单位：
The University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2000
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-11450386/
关键词：
Very Large Floating Structure Wind Load Critical Reynold's Number Column Design Parameter Analysis of Hydro-Elastic Response Safety Response 風荷重目標安全性水平曲げ FAR 揚力許容破壊確率

项目摘要

Initial design procedure of Very Large Floating Structure (VLFS) was proposed compiling knowledge and research results obtained so far. Assuming that the design procedure is proposed for a floating airport to be installed offshore of Japan, environmental conditions used for design of safety and functionability were determined. Initial design was carried out and principal dimensions of airport were determined. The dimension were determined to satisfy the requirement to introduce jet airplane to isolated islands.Basin experiments were carried out using a scale model which is elastically and dynamically similar to real structure, and the response characteristics were clarified. Simple numerical model was proposed for dynamic response of VLFS. This is a simple model, a beam on elastic foundation, but basic response characteristics of the structure is expressed by this model and relations between major parameters and dynamic response were clarified. Furthermore it was made clear that response estimated by this model gives upper limits of that of real structure. These parameters are proposed as design parameters of VLFS.Using the design parameters, an optimal design procedure was proposed. In this procedure resonance is avoided imposing constraints on frequency response and weight of the structure is minimized. Effectiveness of the procedure was confirmed through application to design and analysis.Through initial design, it became clear that the wind drag force occupies major part of the total drag force. Drag force induced by wind is very important in the design of mooring system of the VLFS. A series of wind tunnel experiments were carried out in critical Reynold's number region. Drag force characteristics which act on columns and deck were clarified and multi-step reduction phenomena of drag force was observe and data for estimation of drag force was obtained.

提出了非常大的浮动结构（VLF）的初始设计程序，旨在汇编知识和研究结果。假设提出了为日本海上安装的浮动机场提出的设计程序，则确定了用于设计安全性和功能性的环境条件。进行了最初的设计，并确定了机场的主要维度。确定尺寸以满足将喷气飞机引入孤立岛的要求。使用比例模型进行了basin实验，该模型在弹性和动态上与真实结构进行了动态相似，并阐明了响应特征。提出了简单的数值模型，以进行VLF的动态响应。这是一个简单的模型，是弹性基础上的光束，但是结构的基本响应特征由该模型表达，主要参数与动态响应之间的关系得到了阐明。此外，很明显，该模型估计的响应给出了真实结构的响应。这些参数是作为VLF的设计参数提出的。使用设计参数，提出了最佳的设计过程。在此过程中，避免共振对频率响应施加限制，并将结构的重量最小化。通过应用设计和分析，确认了该过程的有效性。通过初始设计，很明显，风力驱动力占总阻力的主要部分。风在VLF的系泊系统的设计中非常重要。在关键雷诺的数字区域进行了一系列风洞实验。阐明了在柱和甲板上作用的阻力特性，并观察到了阻力的多步减少现象，并获得了用于拖动力的数据。