X形圆钢管相贯节点的轴向滞回性能

Experimental study on the hysteretic behavior of CHS X-joints under cyclic brace axial loads

为了研究X形圆钢管相贯节点在支管轴向荷载作用下的抗震性能,进行了节点在支管轴向往复荷载作用下的试验,分析了节点的延性和耗能模式,以及节点轴拉承载力和轴压承载力之间的差异。研究结果表明:节点的破坏模式为相贯线附近主管管壁塑性软化后开裂破坏;节点的轴力—局部变形滞回曲线饱满,表现出良好的变形能力和延性;节点主要通过相贯线附近主管管壁的塑性变形及裂缝扩展(开裂后)来耗能;节点的轴拉承载力明显高于轴压承载力。

In order to investigate the hysteretic behavior of circle hollow section(CHS)X-joints under cyclic brace axial loads,an experimental test of cyclic brace uniaxial loading is carried.The ductility and energy dissipation of X-joints are studied.The difference between the tensile ultimate capacity(under brace tension)and the compressive ultimate capacity(under brace compression)is analyzed.The results show that the failure model of X-joints is cracking of the chord wall near the brace-to-chord intersection after plastic-softening.The X-joint has a stable hysteretic characteristic and enough energy dissipation capacity and behaves excellent in deformability and ductility.The dissipated energy of X-joints mainly relies on the plastic deformation and crack propagation of the chord wall near the brace-to-chord intersection.It is also found that the tensile ultimate capacity of X-joints is significantly larger than the compressive one.