陈宏洺　郭亚洲　李相国　张淑华

摘 要：为了最大限度提高节点的承载能力，提高海工结构及钢结构稳定性，提出了一种基于弧长法对KT型管节点的承载力进行有限元分析的方法。基于β，τ，γ，θ等4个几何参数对节点承载力的影响规律，最终确定了参数的合理取值：τ取0.75，γ取20，θ取30°～45°，β取0.6～0.8。同时引入参数材料强度比δ，研究支管与主管强度的不匹配对节点承载力的影响，结果显示：随着δ值的增大，节点的承载力先增大后减小再趋于某一值，节点的破坏模式由支管破坏过渡到主管破坏，但承载力的极值点和破坏模式过渡点的δ值的大小会随着τ，γ，β的取值的变化而变化，最终趋于某一个定值。研究结果可为工程上确定加强板的参数取值提供参考。

关键词：结构力学;KT型管节点;承载力;几何参数;材料强度比

中图分类号：TU392.3 文献标识码：A

Abstract：In order to maximize the bearing capacity of the joints and improve the stability of offshore structures and steel structures， a finite element analysis method for the bearing capacity of KTtype pipe joints based on the arc length method was proposed. The influence of four geometric parameters of β， τ， γ and θ on the bearing capacity of the joints was studied. The reasonable range of values of parameters was determined： τ takes 0.75， γ takes 20， θ take 30 °～45 °， β take 0.6～0.8. At the same time， the parameter material strength ratio δ was introduced to study the influence of the strength mismatch between branch pipes and main pipe on the   bearing capacity of the joints. It shows that with the increase of δ value， the bearing capacity of the nodes increases first and then decreases to a certain value. The failure mode of the nodes transits from the branch pipe damage to the main pipe damage， but the δ magnitude value of the ultimate point of the bearing capacity and the transition point of the failure mode will change with the change of the values of τ， γ， and β， and eventually tend to a certain value， which will provide a reference for determining the parameters of reinforcement plate in engineering.

Keywords：structural mechanics; KT tubular joints; bearing capacity; geometric parameters; material strength ratio

近些年，HSS空心管因其優良的力学性能广泛应用于海洋、桥梁、钢结构建筑等工程结构中。鉴于钢管节点在管结构中的重要性，诸多学者对矩形管节点的性能进行了相关的研究。SERRANO等[1]采用试验和有限元模拟研究了16个K型和N型间隙热镀锌矩形钢管节点的静力性能，分析了支主管夹角对节点承载力的影响。FENG等[2]采用数值模拟方法对X，T型矩形管节点的静力性能进行了分析，对节点的承载力公式进行了相应条件下的改进，公式与实际的实验结果吻合较好。LIE等[3]采用试验方法研究了在平面内弯矩作用下，带有裂纹的间隙K型节点的塑性承载力。……