Experimental Study on Repairing Corroded Cracks by Electrophoretic Deposition

Abstract

The corrosion of reinforced concrete could reduce its mechanical properties and cause concrete cracking. Electrophoretic deposition is a new method for repairing rust-cracked reinforced concrete. In this study, we observed the crack surface morphology, mass growth, epoxy resin film thickness, ultrasonic rate, and epoxy resin filling depth of rust-cracked reinforced mortar specimens during the repair process and investigated internal microstructure and phase composition of the repaired mortar, and clarified the principle behind the electrophoretic deposition of cationic epoxy resin and curing agent molecules in the repair solution. The result of research shows that longer repair times decreased the carbonization depth and water absorption of the specimens. After repair, the porosity of the surface mortar decreased, owing to the filling of epoxy resin, and the newly generated epoxy resin film had a dense structure. Thus, the carbonization resistance and waterproof performance of the repaired specimens improved. The repair process of electrophoretic deposition can be divided into the immersion, repair, and curing stages, and the physical and chemical principles of each stage were explained.