平面外弯矩作用下加劲肋加强T形方钢管相贯节点极限承载力研究

Study on Ultimate Bearing Capacity of Rib Stiffener Strengthened Square Tubular T-Type Joints under Out-of-Plane Bending Moment

方钢管T形相贯节点承受平面外弯矩作用是与其它工况一样重要的一种工况,但目前规范中对这种受力模式下的加劲肋加强节点承载力计算公式没有规定,这影响着工程设计的效率与质量。在经试验验证有限元分析准确性的前提下,进行参数化分析和回归分析。结果表明:加劲肋加强节点的极限承载力是无加强节点的2.6倍,承载力提高系数ψ随加劲肋与主管厚度比τ、加劲肋与主管宽度比η的增加而增加,其中参数η的影响更大,提高系数ψ随β增加而减小。在无加劲肋方钢管相贯T形节点平面外受弯承载力计算公式的基础上,通过参数化分析得出有加劲肋时方钢管T形节点平面外弯矩作用下极限承载力计算公式,为这类节点的继续研究和工程应用提供了参考。

The load case of square tubular T-type joints subjected to out-of-plane bending moment is the same important as other load cases.However,there is no ultimate bearing capacity calculation formula related to this load case at present.This paper verifies the accuracy of finite element model by comparing the predictions with test data from reference.Also,parametric analysis and regression analysis are carried out.The analysis results show that the ultimate bearing capacity of rib stiffener strengthened joints is 2.6times of that of unstrengthened joints.The improvement coefficientψof ultimate bearing capacity increases with increasing the parametersτ（ratio of thickness of stiffener to thickness of main tube）andη（ratio of width of stiffener to width of main tube）,andηhas greater influence.The coefficientψdecreases with increasing the parameterβ.Based on the ultimate bearing capacity formula of unstrengthened square tubular T-type joints,a formula for calculating the ultimate capacity of strengthened square tubular T-type joints is obtained.This provides a reference for future studies and applications of this kind of joints.