【作者】 姚建锋；

【导师】 高博青；

【作者基本信息】 浙江大学 ， 结构工程， 2003， 硕士

【摘要】 本文在回顾了穹顶结构的发展及其研究现状之后，提出了一种新型的加肋预应力穹顶结构。这种结构兼有普通网壳及索穹顶结构的优点，具有结构简洁明快、承载力高、施工简便等特点，是一种极有潜力的新型空间结构。本文着重对该结构作了动力分析和稳定性研究，得出如下结论。 文中首先分析了该结构的自振特性，发现该结构频谱密集，结构以竖向振动为主。 接着采用反应谱法和时程分析法对该结构进行了动内力的计算，得到该结构受预应力索非线性的影响，宜采用时程分析法计算动内力的结论。然后，通过对结构在EL-Centro地震波作用下内力和位移时程曲线的分析，发现该加肋预应力穹顶结构具有良好的动力性能；但同时指出在索中没有施加预应力的情况下，结构将容易遭到动力破坏。此外，通过参数分析，发现矢跨比对结构的动内力影响比较明显；而质量对结构动内力的影响不大。 然后本文研究了不用的布索方式对结构动力性能的影响。通过对七种不同布索方式下结构的基频和动内力的比较，得到了斜向索对结构的刚度影响比较大，若需提高结构刚度，应首先考虑布置斜向预应力索的结论。 最后本文对该加肋预应力穹顶结构作了几何非线性稳定分析。通过对该结构的线性解和非线性解的比较，发现结构具有明显的几何非线性特征；对加肋预应力穹顶结构作了屈曲分析，并将它的结果与相应的单层网壳作了比较，得出了由于肋桁架和预应力索的存在，加肋预应力穹顶结构的极限载荷大幅度提高，比一般的单层网壳结构具有更好的稳定性能的结论。同时文中还对不同矢跨比下的该结构作了屈曲分析，发现增加矢高可显著提高结构的极限屈曲荷载，改善结构的几何非线性稳定性能。更多还原

【Abstract】 After reviewed the development and actuality of dome structure,A new type of pre-stressed ribbed dome was presented in this thesis. This structure has the both virtue of common dome and cable dome-its concision,its high capacity and its easiness in construction,and so is a potential new type of spatial structure. In this thesis,the dynamic behaviors and geometrical nonlinear stability have been studied,and these conclusions have been put forward.At first,free vibration characteristic of the structure is analyzed,and it is discovered that the frequencies are denseness,moreover vertical vibration is dominant,the combination of ribbed truss and pre-stressed cables enhanced the structure’s stiffness in some degree.And then,the structure’s dynamic behavior has been investigated and calculated with spectrum and time-history methods,and obtained the conclusion that time-history method should be employed. Afterward,element internal forces and node displacements under the EL-Centro are studied by time-history method,the conclusion was obtained that the pre-stressed ribbed dome structure has a good dynamic performance,but at the same time,it’s been pointed out that the pre-stress is necessary to structure,without it,the structure may be destroyed. Furthermore,after parameter analysis,the following results are obtained:the effect of rise-to-span on the structure’s dynamic internal forces is distinct,while the effect of mass parameter is little.Then the effect of cable arrangements to the structure dynamic behaviors was studied. The free vibration frequencies and dynamic internal forces of seven types of cable arrangements were calculated,and the conclusion that diagonal cables are sensitive to structure stiffness are obtained.At last,geometrical nonlinear stability analysis of the pre-stressed ribbed dome was investigated. The linear solution and nonlinear solution were compared,the structure’s obvious geometrical nonlinear character was found. Then the buckling analysis of the structure was made,and compared corresponding dome,the conclusion was made that ribbed truss and pre-stressed cables improved the structure’s limit buckling load. At one time,the buckling analysis of structures with different rise-to-span were made,and discovered that buckling load and stability can be improved with high rise-to-span.更多还原