方钢管混凝土柱与钢梁框架节点的抗震性能试验研究

为验证方钢管混凝土柱与工形钢梁框架节点的破坏特征和抗震性能,本文进行了A、B两组共6个足尺节点试件的低周反复循环加载试验,其中A组三个试件梁端采用栓-焊连接;B组三个试件梁端为全对接焊接。试验结果表明:6个试件的层间位移延性系数μ≈2.28～3.86,弹性极限层间位移角y≈0.001～0.014,弹塑性极限层间位移角u≈0.0297～0.0424,节点梁柱的相对极限塑性转角θu≈0.0163～0.0343rad,能量耗散系数E≈2.029～2.494;A、B两类节点均有良好的抗震性能,在相同轴压比下A类节点的延性较B类略好一些,而耗能能力B类节点却略大一些,但二者相差不大,均满足结构抗震设计的要求。文章还分析了节点域的剪切变形,给出了改造节点设计的几点建议。

Experimental studies on seismic behavior of concrete-filled steel square tubular column and steel beam joints under cyclic loading

In order to verify the failure modes and seismic behavior of the joints composed of concrete filled steel square tubular column and steel I beams, six full size specimens divided as A and B groups had been tested under cyclic loading. The three specimens of group A are connected by bolt welding and those of group B connected by welding at the ends of beams. Experimental results of the six specimens showed that the story drift ductility ratios μ≈2.28～3.86, elastic limits of story drift ratation y≈0.011～0.014, elastic plastic limits of story drift rotation u≈0.0297～0.0424, relative plastic rotation limits of beam column θu≈0.0163～0.0343rad and energy dissipation ratios E≈2.029～2.494. All the specimens of group A and B had excellent seismic behavior, the ductility of the specimens A was better than specimens B but the energy dissipation capacity of the specimens B was a bit better than specimens A under the same axial compression force ratio. However, both A and B specimens satisfied the requirements of the structural seismic design. At the end of this paper, shear deformations of the joint core zone were also analyzed and some suggestions for improving joint design were presented.