PEC柱-型钢梁半刚性框架抗震性能试验研究

Research on Seismic Performance of Semi-rigid Frame of PEC Column-steel Beam

为了研究PEC柱(partially encased concrete column)-型钢梁半刚性框架的受力特点、滞回性能、延性及破坏模式,对PEC柱-型钢梁顶底角钢连接的半刚性框架进行了低周反复荷载试验。试验共设计了三个框架,参数为轴压比和螺栓边距。通过试验数据得到了此类框架的滞回曲线、刚度退化、延性系数等抗震性能指标,分析了顶底角钢节点的初始转动刚度。试验结果表明:增大轴压比可以提高半刚性框架的极限承载力,承载力提高了8.9%;但延性有所降低,平均位移延性系数减小了37.9%;减小螺栓边距可以提高节点初始刚度,减缓刚度退化,增加框架延性;PEC柱-型钢梁顶底角钢连接的半刚性框架滞回曲线饱满,具有良好的抗震性能。

In order to study the mechanical behavior,hysteretic behavior,ductility and failure mode of semirigid frame of PEC column-steel beam,three specimens were designed and tested under low frequency cyclic loading. The parameters were the axial compression ratio and angle bolts margins. Based on the experimental study,hysteretic curves,stiffness degradation and ductility factors and other seismic performance results were obtained,the initial rotational stiffness of top-seat angle connections were analyzed. The results show that the increasing of axial compression ratio can improve the ultimate bearing capacity of semi-rigid frame,the bearing capacity increased8. 9%,but also reduce the ductility of the frame,the average displacement ductility factor decreased 37. 9%; reducing the angle bolts margins can improve initial rotational stiffness of the joint,reduce the stiffness degradation and increase the ductility of the frame; semi-rigid frame of PEC column-steel beam connected with top- seat angle connections has full hysteretic curves shape and good seismic performance.