空间隔板焊接X形圆钢管相贯节点受力性能试验研究

对3个足尺空间隔板焊接X形圆钢管相贯节点分别进行了轴力作用下的单调加载试验和往复加载试验，得到了节点的破坏模式，并对节点的受力性能包括静力弹性刚度、承载力、延性和滞回性能等进行分析。验证了该种空间隔板焊接节点的构造措施合理，节点的承载能力相对设计工况有两倍以上的安全储备，节点受力安全可靠。运用ABAQUS软件建立有限元分析模型，并与试验结果对比，验证了有限元模型的适用性，并对节点进行设计工况下的内力校核，参数分析结果表明,管径厚比、相贯角度、椭圆连接板厚度及平面外角度对空间隔板焊接节点性能影响较大，节点刚度和承载力随着支管径厚比和平面外角度的增大而降低，随着相贯角度和椭圆连接板厚度的增大而提高。综合试验和有限元分析结果，节点设计要确保支管设计内力不大于节点承载力，增大椭圆板厚度以及补焊椭圆板隐藏焊缝对节点的受力性能改善较好；当设计该类较小相贯角度（小于20°）的节点时，需按节点承载力进行设计，同时考虑轴向刚度对节点受力性能的影响。

Investigation on mechanical behavior of X-shaped welded spatial partition plate tubular joints

Three full-scale welded spatial partition plate tubular joint tests were carried out to examine their static and hysteretic behaivour under axial force.The experiment results reveals the fundamental behavior,including the failure modes, elastic stiffness, bearing capacity, ductility and hysteretic behavior, of the considered joints. The results indicate that the joints are reasonably designed and the bearing capacity is two times more than the design resistance.Non-linear finite element models were established by software ABAQUS. The FE results are shown to agree well with the experiment results, verifying the applibility of FE model. The parametric analysis shows that the diameter-thickness ratio, intersecting angle, thickness of elliptical plate and out-of-plane angle are the most important factors affecting the behavior of the welded spatial partition plate tubular joints. In addtion, the stiffness and bearing capacity of the joints decrease with an increase in the diameter-thickness ratio of the branch pipe and out-of-plane angle, but increase with an increase in the intersecting angle and the thickness of the elliptical connecting plate. Summarizing the test and FE results, it is recommended that the bearing capacity of the branch pipe should not be larger than that of the joint, and thickening the elliptical plate and adding the hidden weld of the elliptical plate can help improve the mechanical behavior of the joint. When a small intersecting angle (less than 20°) is designed,the bearing capacity of the joint governs the design, and the influence of axial stiffness on the behavior of the joint should be considered.