Electrochemical Rehabilitation of Salt-Contaminated Concrete: A Lab Study - UTC

To establish preliminary investigation of key factors affecting the performance of electrochemical chloride extraction (ECE) and electrical injection of corrosion inhibitors (EICI), and to validate a modeling framework that may guide the blueprint of ECE/EICI.

Chloride-induced corrosion of reinforcing steel is the major cause for premature failure of reinforced concrete structures exposed to salt-laden environments. The traditional repair method of corrosion-damaged reinforced concrete consists of replacement of the corrosion damage with chloride-free concrete. However, this technique is not a durable solution, as the chloride-containing materials have not been removed from the structure. Both cathodic protection (CP) and electrochemical chloride extraction (ECE) techniques are proven to extend the service life of a treated structure; however, ECE offers some advantages over the use of CP such as the elimination of continuous power supply and regular maintenance by driving away chloride ions from the negatively charged reinforcing steel and potentially out of the concrete. In addition, electrical injection of corrosion inhibitors (EICI) into concrete is a relatively new technique with promising results. There has been limited research and field trials of ECE and EICI and widespread applications are hampered by the lack of detailed information on the underlying mechanisms and relevant rate-limiting steps. WTI researchers will investigate and validate a modeling framework for the promising techniques of ECE and EICI to treat chloride contamination in concrete.