平面钢管桁架的面外稳定分析模型研究

摘要

受压主管无面外支撑的平面钢管桁架的承载能力主要由其平面外的稳定性控制,而其面外稳定性又主要取决于桁架相贯节点的面外转动刚度.推导K型对称圆钢管相贯节点的面外转动刚度计算公式,进行数值验证,在此基础上建立平面钢管桁架面外稳定分析的杆系有限元模型.进行平面钢管桁架面外稳定性的足尺试验研究,与杆系有限元模型的计算结果进行对比分析.数值分析和试验研究表明:提出的平面钢管桁架的面外稳定分析模型具有较高的计算精度,可以应用于实际工程的分析和设计.%The load-carrying capacity of planar tubular trusses without out-of-plane bracings are usually governed by its out-of-plane flexural stability, which is mainly dependent on the out-of-plane rotation stiffness of the intersected joints in the trusses.A calculation formula is derived and verified numerically for the out-of-plane rotational stiffness of the symmetric CHS K joints.On the basis of the formula, a finite element model is presented for the out-of-plane stability analysis of planar tubular trusses.Full-size experiment on the out-of -plane stability of planar tubular trusses is conducted to compare with the results from the finite element model.Numerical and experimental studies show that the model presented in this paper is accurate for calculating the out-of-plane stability of planar tubular trusses and can be practically applied in analysis and design.