Numerical study on effects of the degree of water saturation on ICCP of chloride-contaminated RC structures
Numerical study on effects of the degree of water saturation on ICCP of chloride-contaminated RC structures
复制标题
水饱和度对氯化物污染RC结构ICCP影响的数值研究
DOI：
10.1016/j.jobe.2021.103619
复制
发表时间：
2021-11-12
影响因子：
6.4
通讯作者：
Fu, Qiang
中科院分区：
文献类型：
--
作者：
Guo, Bingbing;Qiao, Guofu;Fu, Qiang
使用包括氧和离子传输、电极反应和钢极化的数值模型研究了混凝土水饱和度对受氯离子污染的钢筋混凝土（RC）结构的外加电流阴极保护（ICCP）的影响。结果表明，钢表面局部电流密度和电位受饱和程度影响显着。当混凝土饱和度增加时，电压控制式 ICCP 中钢材氢脆的风险可能会增加，此时需要降低施加电压。对于饱和度较高的RC结构，ICCP具有较强的提高钢筋周围pH值和去除Cl-的能力。当混凝土饱和度较低时，如果忽略其对Cl-去除和pH升高的影响，建议使用基于拉普拉斯方程的平稳数值模型来研究或设计ICCP。当混凝土饱和度较高时，建议使用瞬态数值模型，包括氧和离子的传输、电极反应和钢极化。
The effect of the degree of concrete water saturation on impressed current cathodic protection (ICCP) of chloride-contaminated reinforced concrete (RC) structures was investigated using a numerical model that includes transport of oxygen and ions, electrode reactions, and steel polarization. The results indicate that the local current density and potential at the steel surface are significantly affected by the saturation degree. The risk of the hydrogen embrittlement of steel may rise in a voltage-controlled ICCP when the concrete saturation degree increases, and the applied voltage needs to be reduced in this case. For RC structures having a high saturation degree, ICCP has a stronger ability to increase the pH around the steel reinforcement and to remove Cl-. When the concrete saturation degree is low, the stationary numerical model based on the Laplace equation is recommended to investigate or design ICCP if neglecting its effect on the Cl- removal and pH increase. When the concrete saturation degree is high, the time-dependent numerical model, including transport of oxygen and ions, electrode reactions, and steel polarization, is recommended.