In Situ Detection on Electrochemical Chloride Removal of Reinforcement in Concrete by Combined pH/Cl^- Probes

Authors

Jing-jing WANG, State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China;
Shi-gang DONG, College of Energy, and School of Energy Research, Xiamen University, Xiamen 361102, Fujian, China;Follow
Xiao-juan ZHANG, State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China;
Hong-wei LV, College of Energy, and School of Energy Research, Xiamen University, Xiamen 361102, Fujian, China;
Yun-chang WU, State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China;
Rong-gui DU, State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China;
Chang-jian LIN, State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China;College of Energy, and School of Energy Research, Xiamen University, Xiamen 361102, Fujian, China;Follow

Corresponding Author

Shi-gang DONG(sgdong@xmu.edu.cn);
Chang-jian LIN(cjlin@xmu.edu.cn)

Abstract

In this work, the concrete samples polluted by chloride ion were electrochemically treated using galvanostatic technique, and the distributions of chloride ion concentration and pH value in the polluted concretes were in-situ monitored by embedding a combined pH/Cl^- probe during the electrochemical chloride removal. The corrosion behaviors of reinforcing steel in the concrete were simultaneously studied by using linear polarization and electrochemical impedance spectroscopy techniques (EIS). The micro environment of the concrete and corrosion rate of steel were explored during the electrochemical chloride removal. It was indicated that the Cl^- concentration in the concrete pore solution decreased with time, while the pH value around steel increased first in the early stage, and then decreased in a certain extent. The steel in the concrete was cathodically polarized and protected by the applied cathodic current. After the electrochemical chloride removal ceased (namely depolarization)，the corrosion potential of steel was obviously shifted to a positive direction，the corrosion current decreased, and the corrosion resistance increased. This illustrates that the electrochemical chloride removal is enable to improve the corrosive environment of steel in concrete and to decrease the corrosion rate.

Graphical Abstract

Keywords

pH/Cl- probe, electrochemical removal chloride, reinforced concrete, corrosion

DOI Link

https://doi.org/10.13208/j.electrochem.130531

Publication Date

2014-04-28

Online Available Date

2014-04-17

Revised Date

2013-09-23

Received Date

2013-05-31

Recommended Citation

Jing-jing WANG, Shi-gang DONG, Xiao-juan ZHANG, Hong-wei LV, Yun-chang WU, Rong-gui DU, Chang-jian LIN. In Situ Detection on Electrochemical Chloride Removal of Reinforcement in Concrete by Combined pH/Cl^- Probes[J]. Journal of Electrochemistry, 2014 , 20(2): 95-100.
DOI: 10.13208/j.electrochem.130531
Available at: https://jelectrochem.xmu.edu.cn/journal/vol20/iss2/1