带加劲肋十字型钢管节点支管轴压的承载力研究

BEARING CAPACITY OF CROSS-SHAPED STEEL TUBULAR JOINTS WITH REINFORCED PLATE UNDER BRACE COMPRESSION

针对带加劲肋十字型钢管节点采用有限元方法和足尺试验研究其承载力,比较两种方法的计算结果,探讨有限元中钢管节点屈曲的模拟方法,分析加劲肋贯穿对承载力的影响,最后将试验和计算结果与规范进行比较。研究表明:加带加劲肋十字型钢管节点支管轴压的最终破坏形态为环板的面外失稳;有限元中初始缺陷的最大幅值取主管管径的1/1000进行钢管节点屈曲分析是合理的;加劲肋贯穿主管的工艺可以一定程度上提高节点的刚度和承载力。

Finite element simulations and full-scale experiments are employed to study the bearing capacity of cross-shaped tubular joints with reinforced plate under brace compression. The results obtained from the two methods are compared and numerical method to simulate the buckling of the tubular joint is investigated. The influence of the penetration of the reinforced plate into the chord tube on the bearing capacity is studied. Then the results obtained from simulation and experiments are compared with those calculated using the equations provided by the Codes. Results show that the final failure mode of cross-shaped tubular joint with reinforced plate under brace compression is the out-of-plane instability of circular plate. It is reasonable to set the maximum initial imperfection displacement to be 0.001 times of the diameter of the chord tube, so as to simulate the buckling of joints through finite element simulation. The technique of the reinforced plate penetrating into the chord tube can improve the displacement stiffness and the bearing capacity of the joint.