T形、Y形带内置环肋圆钢管相贯节点承载力计算方法

Calculation method for bearing capacities of internal ring-stiffened tubular T- and Y-joints

为了得到T形、Y形带内置环肋圆钢管相贯节点的承载力计算公式，对528个节点进行参数化分析．结果表明：T形、Y形节点的环肋设置在冠点时，对节点承载力提高率的贡献最小，而设置在距冠点到鞍点距离的0.7～0.8倍时，贡献最大；支管受压时，T形带肋节点承载力提高值随环肋厚度和宽度的增大而增大，但受支主管直径比和主管径厚比的影响较小；T形、Y形带肋节点承载力提高值之比受支主管直径比和环肋厚度、宽度的影响较小，而随支主管夹角的增大呈近似线性增加；考虑主管应力比以及支管拉力的影响时，可沿用现行规范中无肋节点的相关参数．结合现行规范，提出了T形和Y形节点的承载力计算公式，适用性检验结果证明了所提公式的可靠性．

In order to obtain calculation equations for the bearing capacities of internal ring-stiffened tubular T-and Y-joints,parametric analysis for 528 tubular joints is carried out.The results show that for T-and Y-joints,the smallest increase in joints’ bearing capacity occurs when the stiffeners are lo-cated on the crown,while the increases are highest when the stiffeners are located 0.7 to 0.8 times of the distance between the crown and the saddle from the crown.When the brace is under compres-sion,the ring-stiffened T-joints’ bearing capacity increases with the increase of the thickness and the width of the ring-stiffeners,and the effects of the ratio of brace diameter to chord diameter and the ratio of chord diameter to chord thickness are insignificant.The ratio of the increase of the bearing capacity of T-joints to that of Y-joints linearly increases with the increase of the angle between the brace and the chord,and the ratio of brace diameter to chord diameter, as well as the thickness and the width of ring-stiffeners are less effective.The related parameters of the unstiffened joints in exist-ing codes can be adopted to investigate the effects of the ratio of chord axial stress and the brace ten-sion.According to the related formulas in existing codes,the calculation equations for T-and Y-joints are proposed and the applicability test demonstrates their reliability.