低周荷载下半刚性梁柱组合节点抗倒塌仿真

Simulation of Anti-Collapse of Semi-Rigid Beam-Column Composite Joints under Low Cyclic Loading

鉴于半刚性梁柱在建筑行业的应用不断增加和该领域现实需求,对低周荷载下半刚性梁柱组合节点抗倒塌性能进行测试,为组合梁柱可靠使用提供依据。共制作3个构件,1个纯钢节点,2个具备同样连接模式的组合节点。将平端板与纯钢相互连接、在侧向荷载条件下选取框架中节点邻接梁柱反弯点间组合体作为组合节点构件,采用十字形构件,设置上下柱的反弯点比例为1:1,仿真结构的梁柱中节点。在构件上安装位移传感器和应变片等设备,用于量测重要部位应力应变与位移等参量。选取SCHENCK电液伺服加载设备进行低周加载,并利用采集系统将测试过程中的数据进行记录。通过量测得到连接转角,作用于柱节点部分腹板位置的剪力。经加载试验测试可知,组合节点的破坏模式分别为钢筋屈服、柱节点部分屈服、混凝土开裂;当低周荷载加载结束,3个构件承载的柱顶荷载较为接近;测试结果与实际值拟合度高于文献成果。

For the increasing application and the actual demand of semi rigid beam-column in construction field,we tested the anti-collapse performance of semi rigid beam-column composite nodes under low cycle load,which provided a basis for the reliable use of composite beam-column.Firstly,we made three construction members,a pure steel joint and two composite joints with the same connection mode.Then,flush end-plate and pure steel were connected.Under the condition of lateral load,the combination between adjacent beam-column contra-flexure points in frame was selected as the composite node component,and the cruciform construction members were adopted.And then,the ratio of contra-flexure points in the upper and lower columns was set as 1:1.Moreover,the beam-column nodes of structure were simulated.In addition,displacement sensors and foil gauges were installed on construction members,which were used to measure the stress,strain,displacement and other parameters of important parts.After that,SCHENCK electro-hydraulic servo loading equipment was selected for low cycle loading and the data in test process was recorded by acquisition system.The shearing force acting on the web plate of column node was obtained by measuring the connection angle.The result of loading test shows that the destroy mode of composite node includes the yielding of reinforcing bar,the yielding of partial node of column and the concrete cracking.When the low cycle load ends,the load on the top of column borne by three construction members is very close to each other.The fitting degree between the test result and the actual value is higher than that of literature results.