During its lifetime, the metallic structure of a building is attacked by the environment, especially by CO2. Indeed, the iron is stable in basic media inside the concrete (pH = 12-14), but carbonates, dissolved in water, will lower the pH localized around the metallic structure. At this acidic pH, the iron is no longer in its passive form but in its corrosive form.
This note demonstrates that electrochemical techniques are able to recondition (electrolysis) and characterize (CPP, impedance, and their corresponding analysis) the metallic structure of buildings.
