矩形钢管焊接球节点的有限元分析与试验研究

Finite element analyses and experiments on welded spherical joints with rectangular tubes

为了解轴力、弯矩及两者共同作用下矩形钢管焊接空心球节点的受力性能与承载能力,进行了有限元分析和试验研究.采用理想弹塑性应力-应变关系、Von-Mises屈服准则,建立了基于几何非线性的有限元模型,对承受轴力、弯矩及它们共同作用的矩形钢管焊接球节点进行了大量的有限元参数分析.对4个典型足尺节点进行了试验研究,直观了解节点的受力性能和破坏机理,并验证了有限元模型的可靠性.研究表明,轴力和弯矩共同作用的焊接球节点的轴力-弯矩相关关系与节点的几何参数无关,极大地简化节点承载力的计算方法.

To investigate the structural performance and load-carrying capacity of welded hollow spherical joints with rectangular tubes subject to axial forces, bending moments and combined loading of the two, finite element analysis and experimental study were carried out. After the elastic-perfectly plastic model and the Von-Mises yield criterion were adopted, a finite element model based on geometric nonlinearity was established. A great deal of parametric studies was carried out for joints subject to axial forces, bending moments and combined loading of the two. Experiments on four typical full-scale joints were conducted to directly understand the structural performance and the collapse mechanism of the joint, and the reliability of the finite element model was validated. Results show that for welded spherical joints subject to combined axial force and bending moments, the axial force-bending moment correlation is independent of their geometric parameters. The correlation can significantly simplify the calculation method for the bearing capacity of the joint.