钢板混凝土复合加固铁路重力式桥墩抗震性能研究

Experimental study on seismic performance of gravity bridge pier reinforced with steel plate and concrete composite

为探究钢板混凝土复合加固震后铁路重力式桥墩的抗震性能,制作配筋率为0.5%的桥墩缩尺模型进行拟静力试验。将模型墩底破坏区域采用钢板混凝土复合加固,对加固后的桥墩模型通过周期往复荷载试验来研究桥墩破坏形态,从滞回曲线、骨架曲线、耗能能力、刚度退化及位移延性等参数分析其抗震性能,并建立有限元模型进行验证。试验结果表明:(1)模型试件中钢板加固桥墩模型墩身部分作为过渡区,避免了加固面受集中力影响导致的破坏面转移;(2)采用钢板混凝土复合加固,可有效提高模型试件的刚度、耗能和承载能力,明显提升了桥墩的抗震能力。该加固方案可用于震后铁路重力式桥墩的修复。

In order to investigate the seismic performance of railway gravity pier reinforced by steel plate and concrete composite after earthquake, a scale model of pier with reinforcement ratio of 0.5% was made for quasi-static test. The damaged area at the bottom of the model pier was reinforced with steel plate concrete composite. The failure mode of the reinforced pier model was studied by periodic reciprocating load test. The seismic performance was analyzed from hysteresis curve, skeleton curve, energy dissipation capacity, stiffness degradation and displacement ductility, and the finite element model was established for verification. The test results show that:(1) The pier body of the steel plate reinforced pier model is used as the transition zone to avoid the failure surface transfer caused by the concentrated force;(2) The steel plate concrete composite reinforcement can effectively improve the stiffness, energy consumption and bearing capacity of the model specimens, and significantly improve the seismic capacity of the bridge pier. The reinforcement scheme can be used for the restoration of gravity bridge pier after earthquake.