预应力损失对逐层双环索穹顶结构静力性能的影响

发布时间：2018-07-26 12:42

【摘要】：索穹顶是一种大跨度空间柔性结构体系,其构思巧妙、受力合理、造型新颖、造价经济、是至今为止最接近于Fuller所定义的张拉整体体系的结构型式。本文在传统葵花型索穹顶结构体系的基础上,提出一种新型葵花型逐层双环索穹顶结构,借助有限元分析软件对环索存在预应力损失、环索滑移等情况下的结构静力性能及新型索杆节点设计等内容进行了相关研究。首先,本文介绍了逐层双环索穹顶结构体系及其张拉成形施工方法,提出了解决其技术问题所采用的技术方案。根据结构的力学特性,提出了一个新型索杆节点,它适用于新型结构体系.具有方便施工、低成本、能与拉索相匹配、既可滑动又可锁住等特点。其次，，本文对考虑施工滑移索摩擦影响的新型葵花型逐层双环索穹顶结构静力特性进行了研究。计算结果表明,环索与节点间的摩擦会导致张拉环索内力分布不均匀,对结构静力性能影响较大。最后,为解决变索原长法在求解索穹顶结构模拟考虑摩擦影响的连续索在节点处滑移问题时存在的不足,本文在其基础上提出了变索原长改进法,使得ansys软件计算过程更加清晰高效。得到了张拉成形后环索滑动与不滑动两种情况下结构的静力性能对比。研究结果表明,滑动环索能使新型葵花型逐层双环索穹顶结构在不对称荷载作用下内力分布更加均匀、各节点位移相应增大。研究结果为新型节点设计提供了思路。
[Abstract]:Cable dome is a kind of long-span space flexible structure system, which has ingenious conception, reasonable force, novel shape and economical cost. So far, cable dome is the most close to the tensioning integral system defined by Fuller. Based on the traditional sunflower cable dome structure system, a new sunflower type double-ring cable dome structure is proposed in this paper. The static performance of the structure and the design of new cable-bar joints are studied. Firstly, this paper introduces the structure system of double-ring cable dome layer by layer and the construction method of tensioning forming, and puts forward the technical scheme to solve the technical problems. According to the mechanical properties of the structure, a new cable-bar joint is proposed, which is suitable for the new structural system. Easy construction, low cost, can match with cable, can slide and lock, etc. Secondly, the static characteristics of a new sunflower double-ring cable dome structure with sliding cable friction are studied in this paper. The results show that the friction between the cables and the joints leads to the uneven distribution of the internal forces of the tension cables, which has a great influence on the static properties of the structures. Finally, in order to solve the shortcoming of the original length method of variable cable in solving the sliding problem of continuous cable with friction effect in cable dome structure simulation, an improved method of changing the original length of cable is proposed in this paper. It makes the calculation process of ansys software more clear and efficient. The static properties of the structure under the conditions of cable sliding and non-sliding after tensioning are obtained. The results show that the sliding ring cable can make the internal force distribution of the new sunflower double-ring cable dome layer by layer more uniform under asymmetric load and the displacement of each node increases accordingly. The results of the study provide ideas for the design of new nodes.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU399

【参考文献】