可更换钢桁架-屈曲约束钢构件组合连梁抗震性能试验研究

Experimental study on seismic behavior of replaceable steel truss composite coupling beams with buckling constrained elements

提出了3种可更换消能减震钢桁架式连梁,即钢桁架-双层高阻尼混凝土板约束钢桁架组合连梁(SCB1)、钢桁架-双层高阻尼混凝土板约束钢板组合连梁(SCB2)与钢桁架-双层高阻尼混凝土板约束钢板阻尼器组合连梁(SCB3)。三种连梁的上下弦杆为内填高阻尼混凝土钢管,其与混凝土剪力墙内的钢结构预埋件铰接。连梁SCB1中的约束钢桁架、连梁SCB2中的约束钢板与混凝土剪力墙内的钢结构预埋件通过摩擦型高强螺栓连接,与上下弦杆通过O型235B钢板连接件焊接。连梁SCB3中的约束钢板仅通过摩擦型高强螺栓与上下弦杆上的耳板连接。通过3个连梁试件的低周往复荷载试验研究了3种可更换消能减震钢桁架式连梁的抗震性能。研究结果表明:3个试件的上下弦杆和钢筋混凝土墙肢试验后没有发生破坏,均能满足震后可更换的要求;试件SCB3的承载能力与变形能力最好,试件SCB2的延性与耗能能力最优;双层高阻尼混凝土板能够有效的限制钢腹板的平面外失稳,O型环连接件能够增强连梁的耗能能力。

In this paper,three new kinds of replaceable steel truss composite coupling beams with buckling constrained elements are presented,namely,steel truss composite coupling beams with buckling constrained steel truss(SCB1),steel truss composite coupling beams with buckling constrained steel web(SCB2)and steel truss composite coupling beams with energy dissipating device(SCB3).The top and bottom chords in the proposed coupling beams are high damping concrete filled steel tube,the buckling constrained elements in the proposed coupling beams are constrained by a couple of precast high damping concrete plate.The top and bottom chords of the proposed coupling beams are pinned to the steel embedment in reinforced concrete walls;the buckling constrained steel truss of the SCB1 and buckling constrained steel web of SCB2 are connected to the steel embedment in reinforced concrete walls by using high strength friction bolts;the O-connectors are welded with the chords and constrained steel truss of the SCB1 and buckling constrained steel web of SCB2.The constrained steel web of SCB3 is only bolted to the chords using fish plates.The seismic behaviors of three kinds of proposed replaceable coupling beams are studied by means of the quasi-static tests of the test specimens SCB1,SCB2 and SCB3.The test result shows that,the visible damage does not occur at the top and bottom chords in the proposed coupling beams and the reinforced concrete wall piers after tests;the specimen SCB3 exhibits the best bearing capacity,and ultimate deformation and the specimen SCB2 appear excellent energy-dissipating capacities and displacement ductility;a couple of precast high damping concrete plate can restrain the buckling constrained elements well,and the O-connector can improve energy-dissipating capacity of the coupling beams.