ABSTRACT
Many repairs of chloride induced corrosion in practice fail within 10 years due to chloride remaining after cleaning the steel, causing corrosion re-activation. An improvement of conventional repair was invented, Electro Active Repair, that electrochemically removes chlorides. After concrete removal, a temporary electrolyte and anode are installed and direct current is applied for 24 hours. Subsequently repair is as usual. Patents have been applied. Laboratory testing confirmed the principle. A cementitious material was placed between NaOH and FeCl2 solutions. More than 90% of the chloride was removed from the catholyte (FeCl2) in 20 hours at 8 A/m2 and the pH increased from 3 to 12. This will suppress re-activation of corrosion and improve the durability of the repair. The method fits in the conventional repair process. The additional cost is moderate. Applying the invention increases repair life and reduces life cycle cost of corrosion affected structures.
