浮托安装工程设计中的若干共性问题的探讨

Discussion on Some Common Issues in Engineering Design of Float-over Installation

论文以荔湾3．1中心平台组块浮托安装工程项目设计、施工为依托，就浮托安装工程设计和分析中遇到的若干共性问题进行了初步归纳和探讨。介绍了浮托安装船的选择要求、浮托法工程设计的安装阶段划分以及各个阶段设计所需的注意事项；阐述了浮托安装设计环境条件选取及对施工可操作性的影响；就荔湾3—1中心平台组块浮托安装工程设计中的数值处理方法进行了归纳和总结；指出了水动力分析中出现的不规则频率对浮托安装分析结果的影响、规避方法和工程处理办法；讨论了系统阻尼比对工程分析结果的影响，并结合工程经验给出了建议；介绍了物理模型试验和现场测量方法的作用和意义。论文探讨了LMU、DSU以及护舷系统等安装辅助设备在工程设计应用中的注意事项，对影响分析结果的若干重要设计参数（如：桩腿耦合缓冲器的水平刚度、组块支撑单元与组块之间的摩擦系数以及横荡护舷间隙等）进行了初步探讨和研究。论文的研究成果对更为合理有效地进行浮托安装设计及施工具有重要参考价值。

Based on Liwan 3-1 CEP float-over engineering and installation project, this paper summarizes some common issues on float-over subject. Requirements for float-over construction vessels, division of installation phases and issues concerned in each division are introduced. Then selection of environmental conditions and their impact on the operability are discussed. Numerical methods used in Liwan 3-1 project are summarized. Influence of irregular frequencies on the analysis result is pointed out and corresponding engineering measures reducing this influence is discussed. Impact of system damping on the engineering analysis result is discussed. Some suggestions are given based on project experiences and physical model test. In addition, on site measuring methods are introduced. Finally, some important issues on of the installation of auxiliary equipment, such as LMU, DSU and fender system are discussed. Some important design parameters （such as lateral stiffness of the LMU, friction coefficient between DAU and topside, the gap between vessel and fender, etc） are investigated that have much influence on analysis results. The research results of this paper have important reference value for the implementation of float-over installation and construction with high reasonability and effectiveness.