（宁夏大学土木与水利工程学院，银川 750021）

［摘要］为探究主管局部加垫板的加强方式对圆管K形搭接节点滞回性能的影响，制作了1个未加强节点和4个垫板加强节点，并对其进行拟静力试验，得到了各节点试件的破坏模式、滞回曲线及骨架曲线，量化评价了节点的承载力、延性和耗能能力，并分析了垫板参数对节点滞回性能的影响。结果表明：未加强节点的破坏模式为主管表面塑性破坏，伴随支管趾部屈曲；垫板加强节点破坏模式为搭接支管屈曲破坏，而主管无明显变形。主管局部加垫板有效地改善了节点力学性能，提高了节点承载力，延缓了主管的塑性变形，避免了在支主管相贯区域主管壁应力集中的问题。垫板厚度和宽度对节点承载力均有一定的影响，当垫板宽度为450mm、厚度为5mm时，节点承载力达到最大416.5kN。利用ANSYS软件对节点试件进行模拟，模拟结果与试验结果整体吻合较好。

［关键词］垫板加强圆管K形搭接节点；拟静力试验；滞回性能；承载力；延性；有限元分析

中图分类号：TU398-7文献标识码：A文章编号：1002-848X(2020)24-0029-06

Experimental study on hysteresis behavior of inserted plate reinforced overlapped K-joints with circular steel tube

YAN Ruhao, YANG Wenwei, MA Pinjun

(School of Civil and Hydraulic Engineering, Ningxia University, Yinchuan 750021， China)

Abstract:In order to investigate the effect of inserted plate reinforced measures on hysteretic behavior of the overlapped K-joints, one unreinforced joint and four inserted plate reinforcement joints were fabricated, and quasi-static test was performed on them. The failure modes, hysteresis curve and skeleton curve of each joint specimen were obtained. The bearing capacity, ductility and energy dissipation of the joints were evaluated quantitatively, and the effect of plate′s parameter on hysteresis behavior of the joints was analyzed. The results show that the failure mode of the unreinforced joints is the plastic failure of the surface of the chord, accompanied by buckling of toe of the brace. The failure mode of the inserted plate reinforced joints is the buckling failure of the overlapped brace while the chord has no obvious deformation. The local inserted plate effectively improves the mechanical properties of the joints, increases the bearing capacity of the joint, delays the plastic deformation of the chords and avoids the large stress concentration of the chord in the area where the braces and chords intersect. The thickness and width of the inserted plate have certain influence on the bearing capacity of the joints. When the width of the inserted plate is 450mm and the thickness is 5mm, the maximum bearing capacity of the joints is 416.5kN. Finally, the ANSYS software was used to simulate the test specimens, and the comparison results are in good agreement with the simulation results.

Keywords:inserted plate reinforced overlapped K-joint; quasi-static test; hysteresis performance; bearing capacity; ductility; finite element analysis

*国家自然科学基金项目（51468054）。

作者简介：闫汝浩，硕士，Email: YRHendeavor@163.com；通信作者：杨文伟，博士，教授，博士生导师，Email: nxyangww@163.com。