国家体育场钢结构设计中的优化技术

针对国家体育场大跨度钢结构中存在用钢量较大的问题,通过对主结构和次结构的布置进行调整,使结构的受力性能与节点构造得到了改善;在板件应力状态分析的基础上,提出了适用于焊接薄壁箱形构件的设计方法;根据主结构与次结构受力的特点,提出合理确定杆件计算长度系数的方法;提出钢结构分段吊装方案,合理确定临时支撑塔架的位置,并考虑安装顺序对结构抗震性能的影响;通过合理选用新型中国产高强钢材,有效地控制了结构自重;在ANSYS软件平台上开发了设计与优化功能,以满足国家体育场复杂大跨度钢结构设计的需求;通过多种布索方案的综合比较,对采用预应力技术的可行性进行了深入的研究。通过对多种优化方法的研究与应用,有效地减小了国家体育场大跨度钢结构的用钢量,并取得了显著的技术进步及社会经济效益。

Optimization Techniques of Steel Structure Design for National Stadium

According to the steel tonnage of National Stadium large-span roof steel structure being relatively large in the original preliminary design,the load bearing capacity and connection characteristics of the structure were improved greatly by means of re-adjustment of the primary structure and secondary structure.The suitable design method for thin-wall weld box section was presented based on the stress analysis of the panels of box sections.According to the structural characteristics of the main truss structure and the secondary structure,the calculation length factors of the compressed members were defined reasonably.Panel by panel erection scheme for the roof structure was presented and the locations of temporary supporting towers were arranged reasonably,the effect of construction procedure on the seismic resisting capacity of the structure was also included in the soon.The proper choice of the domestic high-strength steel reduced the total weight of the structure effectively.In order to satisfy the requirements of the complicated large-span steel structure design of National Stadium,the design and optimization functions were developed based on ANSYS software platform.Feasibility of the prestressed techniques was studied through the comprehensive comparison between several cable arranging schemes.All those effective optimization measures reduced the steel tonnage of National Stadium large-span steel structure and the significant technology;social economic benefits were achieved.