矩形钢管混凝土K型节点受力性能试验

对6个矩形钢管混凝土K型节点和1个矩形钢管K型节点进行了受力性能试验研究,结合Packer试验结果,对矩形钢管混凝土K型节点的破坏模式及节点间隙对节点性能的影响进行了分析,并和矩形钢管节点进行对比,推导了K型节点与Y型节点的判别式。试验结果表明:矩形钢管混凝土K型节点没有发生屈服线破坏模式,节点极限承载力得到了有效的提高;受拉支管破坏模式与矩形钢管节点相似,为冲剪破坏和有效宽度破坏;在满足受压支管承载力的前提下,受压支管为横向局部承压破坏模式;当受压支管宽厚比较大时,可不考虑节点间隙对节点承载力的影响;当受压支管宽厚比较小、节点间隙较大时,需考虑节点间隙对节点极限承载力的影响。

Experiment on Force Performance of Concrete-filled Rectangular Steel Tube K-joints

The force performance tests of 6 specimens of concrete-filled rectangular steel tube(CFRST) K-joints and 1 specimen of hollow rectangular steel tube(HRST) K-joints were carried out,compared with Packer's experimental results,the failure mode of CFRST K-joints and influences on joints performance of joint gap were analyzed contrasting with HRST joints results.The method to differentiate K-joint or Y-joint of CFRST was provided.The experimental results show that yield-line failure mode of CFRST K-joints is not found,and the ultimate bearing capacity of CFRST joints are improved.Like the HRST joints,the failure mode of tension branch is punching failure mode or the effective width failure mode.If the bearing capacity of compressive branch is enough,the failure mode of compressive branch is local transverse compression failure mode of chord.When the ratio of width and thickness of CFRST K-joints is large,the influences of joint gap for bearing capacity can be ignored,while the ratio of width and thickness is small and joint gap is large,the influences of joint gap on K-joints ultimate bearing capacity should be considered.