80 m球径螺栓球节点单层球面网壳稳定性能分析

Analysis of stability of 80m diameter single-layer reticulated dome with bolt-sphere joints

摘要:

螺栓球节点是一类半刚性节点,能否应用到单层网壳中一直是该领域急需解决的关键问题之一,本文首先通过螺栓球节点域的有限元分析,利用已有试验研究结果,获得螺栓球系列节点的弯矩-转角关系,再通过数值方法将其引入到整体网壳的节点刚度模拟中,建立了半刚性节点网壳分析方法．在此基础上,针对沈北新区市民健身中心80 m直径单层球面网壳,采用螺栓球节点连接设计,并进一步对结构施工成形过程中的多个状态进行非线性稳定性分析,也对覆盖饰面材料后网壳的稳定性能进行了探讨．分析结果表明:在施工阶段,网壳局部杆件以受弯为主,导致水平荷载作用下1／2球的极限承载力最低,而竖向荷载作用下的3／4球则因为其上部变形较大导致其极限承载力下降较多;在网壳合拢后,受弯构件转化为以受轴向力为主,其竖向、水平极限承载力分别到达设计荷载的4.7倍和9.2倍,因此只要通过合理措施,避免施工各阶段可能出现的失稳破坏,螺栓球节点完全可以应用到单层网壳结构中．

Abstract:

The bolt-sphere joint belong to the semi-rigid node, whether it can be applied in the single-layer reticulated shells is one of the key problems which is badly in need of being solved in this field. This paper based on the finite element analysis and took advantage of the results of tests of bolt-sphere joints. The moment-rotation curves of bolt-sphere joints are obtained from, then through introducing the node stiffness simulation of shell into the numerical methods, the analysis method of semi-rigid node net shell were set up. On this basis, specific to citizen fitness center in the north new district of shen yang, which is an 80m diameter reticulated spherical shell with bolt-sphere joints, and the nonlinear stability of the different form during the work progress were analyzed, the skin effect of single-layer reticulated spherical shell with bolt-sphere joints were discussed. The result shows that during construction phase, the bending is the major stress form of the part of the reticulated dome’s bars, which result in the ultimate bearing capacity of 1／2 dome under horizontal load is the lowest, and because of the big deformation of dome’s upside, the ultimate bearing capacity of 3／4 dome under vertical load declines largely. After the dome is closed, the bending bars are transformed into being major suffered with axial force, its ultimate bearing capacity reach the 4.7 times of design load under vertical load and 9.2 times under horizontal load, therefore only to adopt rational measures and avoid the buckling failure during the construction phase,the bolt-sphere joints can be applied into the single-layer reticulated shell.