锈蚀钢筋混凝土墩柱的双向拟静力试验

为探讨钢筋锈蚀对混凝土桥墩抗震性能的影响,对2组共10个具有不同锈蚀率的钢筋混凝土墩柱模型进行双向拟静力试验,得到在两个不同轴压比下、钢筋不同腐蚀程度时的滞回曲线.分析了钢筋锈蚀率和轴压比对墩柱模型承载力、刚度、位移延性和滞回耗能等的影响,给出墩柱模型的骨架曲线和刚度退化曲线.结果表明,钢筋锈蚀在一定程度上可改变钢筋混凝土墩柱的破坏形态,尤其是在较大的轴压比下;钢筋锈蚀对钢筋混凝土墩柱的水平承载力和位移延性均有较大影响.

Quasi-static test of corroded RC bridge column under biaxial loading

Corrosion of RC piers will seriously affect the seismic performance of the bridge structure. However, few research works focus on this topic currently. A biaxial quasi-static test was carried out on 10 RC bridge column models with different corrosion rate of rebar, which were divided into two groups and each group had the same axial ratio. The hysteretic curves of each model were obtained from the test. Based on the test results, the influence of the corrosion rate of rebar on the seismic behaviors of corroded RC bridge columns under two different degrees of axial loads,such as horizontal bearing capacity, stiffness, displacement ductility and dissipated energy capacity was studied, and both the skeleton curves and stiffness degradation curves of the models were drawn. Test results show that the corrosion of reinforcement may change the failure mode of the RC bridge column, especially under a larger axial load, and has large effect on the horizontal bearing capacity and the displacement ductility of the RC bridge column. Comparing with the model without corrosion of reinforcement, the bearing capacity and the displacement ductility factor of the RC bridge column model with 15% corrosion rate of rebar were decreased by 19% and 36%, respectively. In addition, corrosion of reinforcement has certain influence on the stiffness degradation and the hysteretic dissipation energy of the RC bridge columns under cyclic loading. The stiffness and the dissipated energy capacity of the RC bridge columns at the same displacement amplitude of the cycle after yielding decrease with the increase of corrosion rate of rebar.