Galvanic Protection for Reinforced Concrete Structures, Whitmore & Ball

Active corrosion mitigation systems for reinforced concrete structures can be defined as methods that provide a protective electrical current to reinforcing steel embedded with the structure. These types of systems fall into three broad categories:

1. Electrochemical treatments;
2. Impressed current cathodic protection; and
3. Galvanic corrosion protection.

Electrochemical treatments such as chloride extraction and realkalization provide a high level of current for a short duration to create a passive environment around the concrete/reinforcing steel interface. Impressed current systems use permanently installed anodes that distribute electrical current provided by an external power source.  These systems provide a high level of control over the amount of current delivered, but the electrical systems must be maintained over time. Galvanic systems provide protective current through the installation of dissimilar metals (also known as sacrificial anodes), which corrode preferentially to the metal to be protected. Since galvanic systems operate naturally without the need for an external power source, they provide a low maintenance approach that is economical for many structures.  (read more)