基于直接计算方法的海上超大型浮式结构物单模块强度分析

海上超大型浮式结构是由若干个与半潜平台相似的浮体通过连接器相连而成的一种新型海上结构,目前对其结构强度分析较少。文章基于直接计算方法,采用SESAM/Hydro D进行超大浮体单模块水动力分析并预报其波浪载荷,进而调用SESAM/Sestra模块进行超大浮体总体强度有限元分析。分析表明,超大浮体的三个连接部位出现了较大应力集中。选取这三处连接部位作为关键节点,采用ANSYS计算该三处关键节点的局部强度。研究结果表明,在横撑与下浮体连接处总体和局部应力均最大,该部位是易产生疲劳破坏的部位,需要重点研究。

The Strength Analysis of single module of VLFS based on direct calculating method

Very Large Floating Structure(VLFS)is a new type of offshore structure ,which is made up of a number of connecting floating bodies that are similar with semi-submersible platform. For the complexity and enormousSsize of VLFS, at present there is little research about its strength analysis. In this article, first of all, hydrodynamic response and waveSloads of VLFS are calculated based on direct calculating method with SESAM/HydroD,and then the global strength is analyzed with SESAM/Sestra. The analysis results show that the three connection parts of VLFS(connection parts between cross brace and floating body,connection parts between columns and upper box,connection parts between columns and floating body)exist higher stress concentration. Hence, the three connection positions would be detailed studied. The local strength of single module are evaluated with ANSYS and the results of global strength analysis are regarded as boundary condition. The results indicate that the Von Mises stress of local strength analysis is generally increased compared to that of global strength analysis ,and the max stress occurs at connection parts between cross brace and floating body .This position is prone to fatigue failure, and focused research should be conducted to it. Through the research in this paper,Ssome theoreticalSfoundation would be laid for the study of multi modulesS.