劲性环梁式钢管混凝土节点滞回性能试验研究

Experimental study on hysteretic behavior of concrete filled steel tube joints with steel reinforced ring-beams

进行了10个劲性环梁式钢管混凝土节点的低周往复荷载的试验研究,探讨了牛腿长度、环梁截面尺寸、钢筋锚固方式、轴压比对节点破坏和抗震性能的影响。结果表明:此类节点有效实现了梁铰破坏机制,满足强柱弱梁的设计原则;牛腿长度及环梁截面尺寸是影响节点力学性能的主要因素,随着牛腿长度及环梁截面尺寸的增加,节点的耗能能力及延性系数均增加,破坏模式由脆性破坏变为延性破坏;钢筋搭接于钢牛腿翼缘即可满足节点的抗震性能。

Low cyclic reversed experiments were carried out on ten specimens of concrete filled steel tube joints with steel reinforced ring-beams. The influences of length of the steel bracket,sectional dimension of the ring-beams,anchorage method of reinforcement and axial compression ratio on joint failure and seismic performance were discussed. The results show that such joints realize the beam hinge failure mechanism effectively,and satisfy the design principle of strong column and weak beam. Length of the steel bracket and sectional dimension of the ring-beam are the main factors affecting the mechanical properties of the joints. With the increase of the length of steel bracket and sectional dimension of the ringbeams,energy dissipation capacity and ductility coefficient of the joints increase,and the failure mode changes from brittle fracture to ductile failure. Lapping of bars in the flange of the steel bracket can meet the requirement of seismic behavior of the joint.