锥头强度的理论分析和简化计算

Theoretical Analysis and Simplified Calculation for Strength of Cone-shaped Connectors in Bolted Spherical Joints

螺栓球节点具有加工和施工安装方便等优点 ,在网架结构工程中得到了大量使用。但是锥头作为螺栓球节点中受力比较复杂的连接构件 ,目前还没有具体的计算方法和设计公式。我国现行《网架结构设计与施工规程》(JGJ 7-91)第4 4 7条规定 ,锥头的任何截面应与连接的钢管等强 ,但如何进行核查未做明确规定。本文用轴对称理论简化计算模型 ,考虑锥头与螺栓的共同作用 ,采用接触元理论求解锥头与螺栓的接触传力。通过单参数分析确定锥头构造尺寸等参数与锥头极限承载力之间的函数形式 ,从而设定回归模式 ,并用正交试验设计理论设计锥头模型 ,采用有限元程序进行弹塑性全过程分析 ,应用多元线性回归理论 ,拟合出锥头的极限承载力公式和设计承载力公式。文末还用推导得出的设计承载力公式对现有生产锥头厂家所生产的锥头进行比较并作了评述。

As the bolted spherical joints can be fabricated and assembled conveniently,they are extensively used in grid structures.Cone shaped connector is one of the most important connectors of the bolted spherical joint,but it is not clearly specified in the current code as how to calculate its strength.Since the cone shaped connector is axially symmetrical under both loading and support conditions,the model of computation can then be simplified.To truly reflect the genuine situation,the model will take into consideration the combined action of cone shaped connector and bolt.In this paper,based on both the theoretical analysis and finite element analysis of the cone shaped connectors,and using multi variable linear regression analysis,a simplified strength formula for computing the ultimate bearing capacity and design bearing capacity of the cone shaped connectors has been derived. Finally,comparison with comment on the recently available cone shaped connectors are presented.