【作者】 李阳；

【导师】 陈志华；

【作者基本信息】 天津大学 ， 结构工程， 2004， 硕士

【摘要】 弦支穹顶结构是由日本川口卫教授提出的一种新型结构形式，其将单层球面网壳与张拉整体巧妙组合在一起，充分发挥各自的优点，并能有效遏制原有结构形式的不足，在大跨度空间结构领域中具有广阔的发展前景。本文作为天津大学钢结构教研室对弦支穹顶系统研究的一部分，以大型通用有限元分析软件 ANSYS 为工具，以结构的静力、稳定性理论分析以及现场实物静力加载试验为重点，对弦支穹顶结构进行了较为深入的研究。考虑到结构的大变形，对弦支穹顶进行非线性静力分析，重点考察不同结构矢跨比情况下弦支穹顶的杆件内力、节点变形以及预应力拉索内力变化等静力性能。研究各种矢跨比、初始缺陷、拉索预应力设定、节点刚度以及边界条件等结构参数对弦支穹顶稳定性能的影响，并与相应单层球面网壳作对比分析。研究表明，矢跨比和节点刚度是影响弦支穹顶稳定性能的首要因素。结构的稳定承载能力随结构矢跨比的增加而增加；刚接节点弦支穹顶的稳定性能远优于铰接结构，而且两种节点刚度的结构中预应力拉索的作用表现有所差别。边界条件的不同对结构的整体稳定性能也有一定的影响。滑动铰支座虽然对于释放温度应力有明显作用，但和三向支座相比其结构的稳定承载力则有较大的降低。此外，通过对包含有不同大小初始缺陷的弦支穹顶结构进行的稳定性分析，发现弦支穹顶对初始缺陷的敏感程度要低于相应的单层球面网壳。结合天津博物馆实际工程，本文完成了柔性索弦支穹顶和刚性杆弦支穹顶两类结构的现场实物静载试验，进一步了解在分级加载的状况下实际弦支穹顶结构的杆件内力、节点变形以及拉索内力的变化。同时将试验数据与理论分析做比较，以验证理论计算与实际结构的一致性。研究发现，两种结果定性分析比较吻合；而由于现场实物试验的局限性以及预应力索张拉操作中存在的一定难度，其具体数值仍略有差别。最后，本文对弦支穹顶进一步研究以及实际推广中的重点难点加以总结。同时，也对应用 ANSYS 对大型空间结构进行稳定性分析时的问题提出了自己的理解。更多还原

【Abstract】 Suspendome structure system is a new kind of hybrid space structure systempresented by Mamoru Kawaguchi in Japan, which combines single-layer reticulatedshell and tensegrity system. Taking full advantages of two systems and avoiding someof their shortcomings, suspendome owns a bright future in the area of large spanspace structure. As a part of the systematical studies on the suspendome system by thesteel-structure staff of Tianjin university, this paper, laying the emphasis on the staticand stability analysis and the static field-test, carries out detailed studies of thestructure with the use of the FEM software ANSYS. Considering structure’s large deformation, non-linear static analysis is carried outto review the static performance including the internal force, the node displacementand the change of the internal force of pre-stressed cables. The influence of different structural factors-- including different rise-span ratios,initial defects of structure, values and proportions of cable pre-stress, node rigidityand boundary conditions-- on the structural stability performance, is discussed indetails by contrast with corresponding single-layer reticulated shells. Studies showthat the rise-span ratio and the node rigidity are key factors influencing the structuralstability performance. The bigger the rise-span ratio is, the bigger the value of criticalload is. The stability performance of structures with rigid nodes is far better than thatof structures with pin nodes, and the capabilities of the pre-stressed cables aredifferent for these two kinds of structures. Also boundary conditions have influenceon the stability performance. Sliding supports make the structural stabilityperformance much worse than fixed supports. It is also confirmed that the sensibilityto initial defect of suspendome is less than that of corresponding single-layerreticulated dome. To find out the real performance of the structure under stepped loads, static fieldtests of flexible cable suspendome and rigid bar suspendome are carried out. Thequalitative comparison between test results and theoretical analysis is coherent. Dueto the actual difficulties in the field test and the stretching process of the pre-stresscables, there still is difference in the detailed quantitative analysis.更多还原