十字形钢管混凝土柱框架中节点抗震性能试验研究

Experimental research on seismic behavior of interior joints in the composite frame consisting of CFST crisscross section columns and steel beams

以十字形截面钢管混凝土异形柱-钢梁框架中柱节点为研究对象,按1∶2比例设计了4个弱节点和强节点模型,通过施加恒定轴压比的竖向荷载和低周反复水平荷载,对节点模型进行了加载破坏试验。试验结果表明:弱节点试件破坏形态为节点核心区剪切破坏,随轴压比增大,试件受剪承载力提高,但其延性性能降低;强节点试件破坏形态为梁端受弯破坏,破坏前经历了较大的塑性变形,延性系数达到了5.65。由此可见,合理地设计钢管混凝土异形柱-钢梁框架中节点,可保证其延性破坏,实现"强柱弱梁,节点更强"的设计原则,满足抗震性能要求。

By taking interior joints in the composite frame consisting of concrete-filled steel tubular（CFST） crisscross section columns and steel beams as the research objects,4 one half scaled models of the weak joints and the strong joints were designed and manufactured,and the destruction test on the models was carried out under vertical stable loads and lateral cyclic loads.The test results show that the failure mode of the weak joints is the shear failure in the panel zone,and that of the strong joints is the bending failure at the beam end.With the increasing of the axial compression ratio,the shear bearing capacity of the weak joints increases,however,the deformation capacity and ductility decrease.The strong joint undergoes a large plastic deformation before the damage,and the effective ductility factor of the model reaches 5.51.The interior joint in the composite frame consisting of CFST crisscross section columns and steel beams has the ductile damage by the rational design,and meets the demands of seismic design,that is strong column,weak beam,stronger joint.