局部锈蚀矩形RC墩重度震损后加固试验研究

Experimental study on seismic reinforcement of severe damaged rectangle RC piers with corrosion in local area

为探究局部锈蚀矩形截面钢筋混凝土(RC)桥墩重度震损加固后的抗震性能,本文对拟静力破坏后的6个矩形截面RC桥墩试件进行扩大截面加固。通过加载试验,对加固桥墩试件从破坏形态、滞回特性、水平承载力、位移延性、侧向刚度以及耗能等方面进行了系统分析。结果表明:相比于普通箍筋,横向施加预应力的改进扩大截面加固方式对破坏后桥墩试件的抗震性能修复成效更佳;在同等位移幅值下,锈蚀率不断增大,桥墩试件抗震性能呈现逐渐降低的趋势;钢筋锈蚀位置上移,加固后桥墩试件的抗震性能提升;轴压比加大,加固后桥墩试件承载力和侧向刚度增大,但延性降低。

In order to investigate the seismic behavior of reinforced concrete(RC)piers with partially corroded rectangular section under severe earthquake damage,six RC piers with rectangular section after quasi-static failure are strengthened by enlarging section. Through loading test,the failure mode,hysteretic characteristics,horizontal bearing capacity,displacement ductility,lateral stiffness and energy dissipation of the strengthened pier are systematically analyzed. The results show that the seismic performance of the damaged pier is better when the transverse prestress is applied compared with the common stirrups;under the condition of the same displacement amplitude,the anti-seismic performance of bridge pier decreases gradually with the increasing of corrosion rate;the seismic performance of the reinforced piers increases when the corrosion position of the reinforcement moves up;the bearing capacity and lateral stiffness of the reinforced piers increase and the ductility decreases when the axial compression ratio increases.