Effect of Electrochemical Chloride Extraction on the Steel Reinforced Concrete

Abstract:

Electrochemical chloride extraction (ECE) is used for the rehabilitation of chloride-contaminated concrete. High current densities of steel surface are applied between the steel and a temporary external anode which is placed on the concrete surface. Anions are pushed away from the cathode (steel reinforcement), and cations are accumulated at the cathode. In this study chloride ions were found in the electrolyte during ECE. The extraction efficiency of chlorides was obvious. After treatment, the amount of chlorides around the reinforcement was greatly reduced. ECE had insignificant effect on the compressive strength. Steel potentials in treated specimens showed a strong shift towards more positive values, while potentials in control specimens remained strongly negative.

• Periodical: Key Engineering Materials (Volumes 400-402)
• Pages: 221-225
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.400-402.221
• Online since: October 2008
• Authors: Jian Zhi Xu, Zhu Ding, Feng Xing
• Keywords: Corrosion Potential, Electrochemical Chloride Extraction, Removal Efficiency, Repassivation, Resistance

References

[1] Swamy RN, Corrosion and corrosion protection of steel in concrete, in: Proceedings of international conference, Sheffield, vols. I and II, Sheffield Academic Press; 1994, ISBN 1 85075 723 2, p.1566.

[2] Swamy RN, Hamada H and Laiw JC, A critical evaluation of chloride penetration into concrete in marine environment, in: Proceedings of international conference on corrosion and corrosion protection of steel in concrete, Sheffield, 1994, pp.404-19.

[3] Tanikawa S, Swamy RN, Unprotected and protected concrete: on site chloride penetration with time in an aggressive environment, in: Proceedings of an international conference on corrosion and corrosion protection of steel in concrete, Sheffield, 1994, pp.1069-80.

[4] Swamy RN, Holistic design: key to sustainability in concrete construction, in: Struct Build 2001, 146(4): 371-9.

[5] Swamy RN, Holistic design of concrete technology - the only route to durability and sustainability in construction, in: Proceedings, second international symposium on cement and concrete technology in the 2000s, Istanbul, September 2000, pp.58-72.

[6] J.C. Orellan, G. Escadeillas and G. Arliguie, Electrochemical chloride extraction: efficiency and side effects, in: Cement and Concrete Research, 34(2004), 227-234.

DOI: 10.1016/j.cemconres.2003.07.001

[7] M. Siegwart, J.F. Lyness, B.J. McFarland and G. Doyle, The effect of electrochemical chloride extraction on pre-stressed concrete, in Construction and Building Materials, 19(2005), 585-594.

DOI: 10.1016/j.conbuildmat.2005.01.012

[8] Annual Book of ASTM Standards, 04, 02 Concrete and Aggregates, C876.