基于多尺度模型大悬挑钢结构力学性能分析

Mechanical properties analysis of large cantilevered steel structures based on a multi‑scale model

【目的】考察单尺度与多尺度模型对结构受力性能的影响。【方法】以太原南站屋盖大悬挑钢结构为研究对象,针对其关键节点(68#相贯节点)进行静力足尺试验及理论分析,提出“混凝土+横隔板”的细部构造措施,并与原节点构造措施进行对比分析,同时基于midas Gen软件建立结构整体单尺度模型及含关键节点的多尺度模型,重点探讨结构的稳定性、动力响应等力学性能。【结果】相对于原节点构造措施,“C40混凝土+5道横隔板”细部构造措施的承载力满足要求且具有一定的经济性;与单尺度模型相比,多尺度模型结构的整体应力降低了9.70%;多尺度模型结构中关键节点的受力与单独节点的受力之间差异明显,其变形及应力分别降低了6.53%和25.73%。【结论】多尺度模型可以更真实地模拟结构的受力特性,其结果更精确。

[Purposes]This study aims to investigate the influence of the single⁃scale and multi⁃scale models on the mechanical properties of the structure.[Methods]The large cantilever steel structure of Taiyuan south railway station roof is taken as the research object,the static full⁃scale test and theoretical analysis are carried out for the key joint(68#tubular joint).A detail construction method of“concrete+transverse diaphragm”was proposed and compared with the original joint construction method.Meanwhile,the single⁃scale model of the whole structure and the multi⁃scale model of key joints are established based on the midas Gen software.Then,the mechanical properties such as stability and dynamic response of the structure are particularly discussed.[Findings]Compared with the original joint construction,the bearing capacity of“C40 concrete+5 transverse diaphragm”detail construction meets the requirements and has certain economy;Compared with the single⁃scale model,the overall stress of the multi⁃scale model structure is reduced by 9.70%;In the multi⁃scale model,the stress of the key joint is significantly different from that of the single joint,and the deformation and stress are reduced by 6.53%and 25.73%,respectively.[Conclusions]The multi⁃scale model can more realistically simulate the mechanical characteristics of the structure,and the results are more accurate.