超大型浮体横撑结构极限强度分析

Study on ultimate strength of braced structure of Very Large Floating Structure

超大型浮体(VLFS)的横撑是整个结构的关键部位,极易发生破坏,因此有必要对超大型浮体横撑结构进行极限强度分析。文章以超大型浮体横撑为研究对象,计算其在两端受压、受拉、受剪切和受弯矩作用下的极限承载力,分析其失效模式,并讨论边界约束、初始缺陷和海水腐蚀等因素对撑杆结构极限承载力的影响。结果表明,撑杆结构受压失效模式表现为屈曲失效和塑性变形;受拉、受剪和受弯失效模式表现为屈服和塑性流动;边界条件、初始缺陷和腐蚀对撑杆结构的极限承载力具有一定的影响。文中研究结果可为超大型浮体横撑结构设计和安全可靠性分析提供相关依据。

The brace of Very Large Floating Structure(VLFS)is the weakest and the most critical part of the whole structure,and it is prone to be damaged.So the ultimate strength analysis of the braced structure is necessary.In this paper,the ultimate bearing capacity of the braced structure of the single module of the VLFS under the state of tension,compression,shear and bending are calculated,and their failure modes are analyzed.At the same time,the influence of boundary condition,initial defects and corrosion on the ulti鄄mate bearing capacity of the braced structure are studied.The results show that the failure mode of the braced structure of the VLFS under the state of compression is buckling failure and plastic deformation,and the failure mode of the braced structure under the state of tensile,shear and bending is yielding and plastic flow.Initial deflection and corrosion have mainly an effect on its ultimate bearing capacity.The results of the study provide a basis for the design of the braced structure and the analysis of safe reliability of VLFS.