装配式矩形钢管混凝土柱-钢梁侧板连接节点抗震性能研究

Study on seismic performance of prefabricated CFST rectangular column to steel beam connections with side plate

为解决侧板式焊接梁柱节点震后修复困难的问题,提出一种装配式矩形钢管混凝土柱-钢梁侧板连接节点,该节点通过侧板固定不同形式的金属阻尼器和销轴实现梁柱韧性连接。分别对设置约束型阻尼器、U形阻尼器、S形阻尼器的5个节点试件进行了低周反复试验和有限元分析,研究了金属屈服型阻尼器类型、耗能板约束形式和厚度等因素对装配式矩形钢管混凝土柱-钢梁侧板连接节点抗震性能及震后易修复性能的影响,并通过有限元参数分析研究了S形阻尼器耗能板弯弧角度对节点抗震性能的影响。结果表明:5个节点试件均具有良好的抗震性能,更换阻尼器可实现节点功能的快速恢复;对比3种节点试件的极限荷载和初始刚度,设置约束型阻尼器节点试件的最高,S形阻尼器节点试件的其次,U形阻尼器节点试件的最低;垫板刚度对约束型阻尼器节点试件极限荷载和抗震性能的影响很小,采用刚性垫板可提高节点试件的残余承载力;设置S形阻尼器节点试件的延性和总耗能显著高于其他节点试件的;增大耗能板厚度可提高设置U形阻尼器节点试件的受力性能,但效果不够显著。有限元参数分析结果表明,减小耗能板弯弧角度可显著提高设置S形阻尼器节点试件的极限荷载和初始刚度,耗能板弯弧角度宜在60°~90°范围内。

Side plate welded beam-column joints are difficult to repair after earthquake.In order to solve this problem,a type of prefabricated concrete-filled rectangular steel tubular(CFRST)column-steel beam connections with side plate was proposed.The beam-column connection was realized by fixing different forms of metal dampers and pin shafts via the side plate.Low-cycle repeated tests and finite element analysis were carried out on five joint specimens using constrained dampers,U-shaped dampers and S-shaped dampers.The effects of metal yielding damper type,energy dissipated plate constraint form and thickness on the seismic performance and post-earthquake reparability of prefabricated CFRST column-steel beam connections with side plate were studied.The influence of the bend angle of the S-shaped damper energy dissipated plate on the seismic performance of the connections was studied by finite element parametric analysis.The results show that the five connections have good seismic performance,and the replacement of dampers can achieve rapid recovery of connection function.Comparing the ultimate load and initial stiffness of the three connections,the constrained damper connection is the highest,followed by the S-shaped damper connection,and the U-shaped damper connection is the lowest.The stiffness of the pad has little effect on the ultimate load and seismic performance of the constrained damper connection.The rigid pad can improve the residual capacity of the connection.The ductility and total energy dissipation of S-shaped damper connections are significantly higher than those of other connections.Increasing the thickness of the energy dissipated plate can improve the mechanical performance of the U-shaped damper connection,but the effect is not significant.The results from finite element parametric analysis show that reducing the bend angle of the energy dissipated plate can significantly improve the ultimate load and initial stiffness of the S-shaped damper connection,and the bend angle of the energy dissipated plate should be in the range of 60°-90°.