This document specifies a procedure for carrying out impressed current electrochemical chloride extraction from chloride bearing concrete in existing structures. It is applicable to atmospherically exposed parts of structures with ordinary reinforcement and/ or post-tensioned tendon ducts embedded in concrete. In the latter case, it is essential to verify that there is no risk of hydrogen embrittlement, if necessary by conducting trials and installing monitoring during the treatment.
This document does not apply to concrete containing pre-stressing steel, which can suffer hydrogen embrittlement during chloride extraction, or to concrete containing coated or galvanized reinforcement.
In case of post-tensioned, pre-stressing concrete, the endangered tendon strands can be shielded by the tendon ducts from unwanted and/or exceeded polarization into the cathodic range and respective water reduction.