The Effect of Electrochemical Chloride Extraction Treatment on the Microstructure and Mechanical Properties of Cementitiuos Materials

Electrochemical chloride extraction is a rehabilitation process aimed at reducing the chloride levels of contaminated reinforced concrete structures to below the critical values for corrosion of the reinforcing steel (rebar). This research attempts to characterize the changes in concrete and mortar, particularly at their interface with the rebar, due to an extraction treatment. To this end, concrete specimens with 3.0 percent Cl- by mass of cement, and mortar specimens with 2.0 percent Cl- by mass of the cement were cast, cured and, after various exposures, subjected to electrochemical chloride extraction treatments typical of those applied commercially. It is clear from this study that the structure and mechanical properties of the concrete immediately adjacent to the reinforcing steel are severely degraded by the electrochemical extraction treatment.