电化学修复后钢筋低周疲劳性能退化的时间效应及其影响  

Time Effect of the Low Cycle Fatigue Property Degradation of Reinforcement After Electrochemical Repair and Its Influence

作　　者：毛江鸿 薛倩倩 张军 罗林[3] 马佳星 MAO Jianghong;XUE Qianqian;ZHANG Jun;LUO Lin;MA Jiaxing(College of Architecture&Environment,Sichuan University,Chengdu 610065,China;School of Civil Engineering and Architecture,Ningbo Tech University,Ningbo 315100,Zhejiang,China;School of Civil Engineering,Chongqing Jiaotong University,Chongqing 400074,China)

机构地区：[1]四川大学建筑与环境学院,成都610065 [2]浙大宁波理工学院土木建筑工程学院,浙江宁波315100 [3]重庆交通大学土木工程学院,重庆400074

出　　处：《材料导报》2022年第12期71-77,共7页Materials Reports

基　　金：国家自然科学基金(51878610,51638013,51820105012,51908496);浙江省自然科学基金(LQ19E080008);宁波市自然科学基金(202003N4313);宁波市“科技创新2025”重大专项(2020Z056)。

摘　　要：对电化学修复后经过不同静置时间的钢筋进行了低周疲劳试验,通过疲劳寿命、滞回曲线、剩余强度等力学性能指标研究了静置时间对电化学修复后钢筋疲劳性能的影响,并推导得到不同静置时间下钢筋疲劳的本构参数,基于此本构进行数值模拟,探究了静置时间对电化学修复后桥墩抗震性能的影响。结果表明,电化学修复后钢筋的疲劳寿命和总耗能能力分别下降了12%~23%及13.2%~30%;随着电流的介入,钢筋软化阶段提前,其塑性损伤发展增快,强度和刚度下降速率增大,疲劳失效进程也加快;随着静置时间的延长,钢筋的疲劳性能在第30 d基本恢复至原有水平,且软化阶段延后,钢筋的塑性性能得到恢复;电化学修复后钢筋疲劳性能的退化会导致构件耗能能力下降和延性退化,但随着静置时间的延长其抗震性能得以恢复。The effect of resting time on the reinforcing steel bar’s fatigue performance after electrochemical repair was investigated in this work. The fatigue life, hysteresis curve, residual strength and other mechanical property indexes were obtained by experiments. And the Low-cycle fatigue constitutive model of reinforcing steel bar was established based on experimental data. The effect of resting time on the seismic performance of the bridge pier after electrochemical repair was investigated via numerical simulation. Results show that the fatigue life and total energy dissipation capacity of the reinforcing steel bar after electrochemical repair decreas by 12%-23% and 13.2%-30%, respectively. The softening stage is advanced with the current density increasing. Meanwhile, the development of plastic damage, strength and stiffness reduction rates were accelerated. The fatigue performance of reinforcing steel bar basically recovers to the level of control group after a resting time of 30 d, including the delaying of softening stage and the recovering of plastic properties. The fatigue performance degradation of reinforcing steel after electrochemical repair will lead to the energy dissipation capacity decrease and ductility degradation of reinforced concrete component which can also recover with the resting time.

关 键 词：氢脆 电化学修复 时间效应 低周疲劳 抗震性能 

分 类 号：TU37[建筑科学—结构工程]