超大型浮体单模块在典型波浪载荷下的强度分析

摘要

Very large floating structures (VLFS)are made of several same single modules,and the analysis of the strength of single module is the basis of the strength analysis of VLFS.So the calculation of single module of VLFS in typical wave loading cases is necessary.In this paper,firstly,according to the DNV specification and the transverse pontoon of feature of the VLFS,four typical loading cases—longitudinal split case,longitudinal torsion case,horizontal shear case,and vertical bend case—are selected.Then,a long term prediction of wave loads is studied with the finite element software SESAM.Finally,the global strength of the single module of the VLFS in four typical loading cases are calculated based on the direct calculating method.The results show that the stress distribution of the total structure is uniform,and there are three areas of high stress—the joint of the columns and the upper box,the joint of the column and the pontoon,and the size change area of the brace.Our research provide a theoretical foundation for the design of the VLFS.%超大型海上浮式结构物（very large floating structures，VLFS）由多个模块组成，单模块结构强度是研究超大型海上浮式结构物强度的基础，因此，有必要对超大型浮体单模块在典型波浪载荷下进行强度分析。首先根据挪威船级社（DNV）海上浮式结构物强度分析的相关规范，考虑该超大型海上浮式结构物单模块下浮体横向设置的特点，选取了纵向分离、纵向扭转、横向剪切和垂向弯曲4种典型波浪载荷工况；然后采用SESAM有限元分析软件，对波浪载荷进行长期预报；最后基于有限元直接计算方法对超大型海上浮式结构物单模块在4种典型工况下的强度进行计算，分析得到结构整体应力水平分布均匀，但存在上箱体和立柱连接处部位、下浮体和立柱连接处、撑杆几何尺寸变化3处高应力区的相关结论，为超大型海上浮式结构物的结构设计提供了相关理论依据。