【作者】 赵宪波；

【导师】 叶继红；

【作者基本信息】 东南大学 ， 防灾减灾工程， 2005， 硕士

【摘要】 张弦梁结构是大跨空间结构中的一种,由于具有优良的受力特性,目前该类结构的研究和应用已经兴起。关于此类结构的研究主要集中于两个方面:结构的零状态形状确定和使用阶段受力性能分析,本文的研究工作也集中于此。1、对张弦梁(桁架)结构的找形问题进行了深入研究,根据该类结构的受力特点,提出了分级卸载法,分别用于一端张拉和两端张拉施工方式的找形分析。该方法无需假定结构零状态几何,便可以一次得到对应于初状态(即预应力态)的结构施工放样尺寸(即零状态几何)。本文还通过分级加载对该方法的精度进行了检验。在此基础上,本文对比分析了不同施工张拉方式对结构零状态几何的影响,得出施工方式的不同不会影响结构零状态形状的结论。另外,本文对张拉过程中胎架与结构之间的摩擦力对成形的影响也进行了细致分析,发现在一定条件下,选用适当的施工控制原则,其对结构成形的影响可以忽略。本文参考郑州国际会议展览中心屋盖工程,将分级卸载法应用于张弦空间结构的零状态形状确定问题,发现分级卸载法对该类结构的找形同样适用。2、分析了张弦梁(桁架)结构在使用阶段的静力性能,重点讨论了在常见的最不利工况下,初始预应力幅值、矢高比与垂跨比、拱截面惯性矩(桁架截面高度)和撑杆间距及数目等四个参数对张弦梁(桁架)结构静力性能的影响,得出了一些实用性结论供设计参考。最后,在总结上述研究结果的基础上,本文对张弦梁(桁架)结构的设计、施工和进一步的研究工作提出了建议。更多还原

【Abstract】 The beam (truss) string structure is a sort of long-span space structures. Because of its excellent static mechanical characteristics, it has been studied and used widely. At present, it mainly focuses on the research into form finding and static mechanical behavior of beam (truss) string structures. This paper is also aimed at the two issues.In the paper the problem of form finding of the beam (truss) string structures is studied and the method named offload by steps is put forward in accordance with the mechanical behavior of the structures. The method is applicable to not only the beam (truss) string structures stretched at one end, but also to the structures stretched at both ends. The form of unstrained state can be found based on that of pre-stressed state straightly, i.e. it need not assume the form of unstrained state firstly by means of offload by steps approach, whose precision has been tested by the numerical solution of loading by steps. Furthermore, the forms of unstrained state relative to two different stretching construction methods are compared and it comes to the conclusion that the stretching patterns have no effect on the form of unstrained state. Besides, the friction force of tension bed has also been taken into account in the paper, and it shows that the influence of friction force on form finding can be neglected under certain conditions. The calculating model in reference to Zhengzhou International Center of Conference and Exhibition has been established, and the form related to the unstrained state has been found by offload by steps method. It means that the form finding method proposed in the paper is also applicable to the spatial string structures.The effects of four parameters such as pre-stressed value of cable, rise-span ratio of arch and rag-span ratio of cable, moment of inertia of arch (height of truss section), and the number of struts, on static mechanical characteristics of the beam (truss) string structures are analyzed in the most disadvantage work condition. Finally, some available conclusions are achieved.Based on the above research work, some suggestions of design, as well as of construction are put forward.更多还原