电化学修复后混凝土柱抗震性能的数值分析与验证

Numerical Analysis and Verification of Seismic Performance of Concrete Columns After Electrochemical Repair

为掌握电化学修复对混凝土结构抗震性能的影响,本文进行了常规电场强度下混凝土柱抗震性能的数值分析与试验验证。开展了电化学修复后钢筋低周疲劳试验,基于试验数据对OpenSees有限元平台中的Reinforcing Steel材料的本构疲劳破坏参数C_(f)、强度退化参数C_(d)和疲劳破坏指数α进行修正;开展了电化学修复前后混凝土柱的低周往复试验,得到了电化学修复对混凝土柱抗震性能指标的影响,建立了电化学修复后混凝土柱有限元纤维模型,并对比分析了数值模拟结果和试验数据。结果表明:钢筋低周疲劳试验加载幅值为±1.0%、±1.6%、±2.0%时,电化学修复钢筋试件比未修复钢筋试件的疲劳寿命分别降低约5%、30%、54%,说明电化学修复过程中产生的氢对钢筋的低周疲劳寿命负面影响随幅值的增大而增大;基于不同加载幅值下的钢筋低周疲劳数据,通过Coffin-Manson疲劳模型拟合得到考虑电化学修复后影响的本构参数C_(f)、C_(d)及α分别为0.136、0.361及0.410;电化学修复前后混凝土柱的滞回曲线形状基本一致,峰值荷载与耗能能力基本相同,说明常用电流下的电化学修复对混凝土柱的抗震性能影响较小;混凝土柱的数值模拟结果和低周往复试验结果接近,说明本文提出的有限元纤维模型可用于评估电化学修复对混凝土构件抗震性能的影响。

To grasp the effect of electrochemical repair on the seismic performance of concrete structures,numerical analysis and experimental verification of the seismic performance of concrete columns under conventional electric field strength are investigated.First,low-cycle fatigue experiments of steel bars were performed after electrochemical hydrogen charging,and the constitutive parameters C_(f),C_(d),andαof the reinforcing steel material were corrected in the OpenSees platform based on the test data.Second,low cyclic loading experiments of concrete columns were performed after electrochemical repair,and the effects of electrochemical repair on the seismic performance index of concrete columns were obtained.Finally,a finite element fiber model of the concrete column after electrochemical repair was established,and the numerical simulation results and experimental data were compared and analyzed.The results showed that the fatigue life of the electrochemically repaired steel specimens was reduced by about 5%,30%,and 54%compared with that of the unrepaired steel specimens at loading amplitudes of±1.0%,±1.6%,and±2.0%for the low circumference fatigue test of steel bars,respectively,indicating that the negative effect of hydrogen generated during electrochemical repair on the low circumference fatigue life of steel bars increased with the increase in amplitude;the shape of hysteresis curves of concrete columns before and after electrochemical repair was basically the same,and the peak load and energy dissipation capacity were also basically the same,indicating that electrochemical repair at common currents had a small effect on the seismic performance of concrete columns;the numerical simulation results of concrete columns were close to those of low cyclic loading experiments,indicating that the finite element fiber model proposed in this paper could be used to evaluate the effect of electrochemical repair on the seismic performance of concrete members.