梁端约束H型钢梁-柱节点的火灾后力学性能试验研究

Experimental Research on Post-Fire Mechanical Properties of H-Steel Beam to Column Connection with Restraint at Beam Ends

通过对6组火灾后梁端约束H型钢梁-柱节点(JD2-2未经过受火试验)进行拟静力试验,得到节点滞回曲线及骨架曲线,分析了试件的承载力、刚度退化、延性及耗能能力的变化情况。研究结果表明:两端外伸端板连接节点具有良好的变形及耗能能力,一端外伸端板连接节点耗能能力较弱,适用于非抗震区;火灾作用使节点的强度、刚度及延性均有所下降,对耗能能力无影响;增加端板厚度可以提高火灾后节点的承载力和耗能能力,但对改善火灾后节点的延性作用不大;梁端设置加劲肋和端板下部设置抗剪支托可以提高火灾后节点的延性及耗能能力,但对火灾后节点承载力的提高不明显。

The quasi-static test was carried out on 6 sets of H-steel beam to column connections with restraint at beam ends(JD2-2 had not passed the fire test),hysteretic curves and skeleton curves of joints were obtained,the bearing capacity,stiffness degradation,ductility and energy dissipation capacity of specimens were analyzed.The results showed that two-end extended end-plate connection joint had good deformation and energy dissipation capacity,the energy dissipation capacity of the one-end extended end-plate connection joint was weak and applicable to non-seismic zone;the strength,stiffness and ductility of joint were reduced by fire,and there was no effect on the energy dissipation capacity;Increasing the end-plate thickness could improve the bearing capacity and energy dissipation capacity of the joint after fire,it had little effect on improving the ductility of joint after fire;the ductility and energy dissipation capacity of the joint could be improved by setting stiffeners at beam ends and shear brackets at the bottom of the end plate,but the bearing capacity of the joint was not improved obviously after fire.