Experimental Investigation of Re-Corrosion Phenomenon in Simulated Repaired Steel Reinforced Self Consolidating Concrete Structures

This paper aims at investigating the phenomenon of macro-cell corrosion in the reinforcing steel of repaired chloride-contaminated self compacting concrete (SCC) patches. Self consolidating concrete because of its workability and stability is now a centre of focus among researchers and engineers working in the field of construction and repairs. Few researchers found SCC as a good repair material then ordinary concrete. But the literature and research relating to the repair of SCC concrete structures patches is limited. Therefore, thorough research has been carried in this paper to investigate the above said phenomenon. In this research, four prismatic specimens with two sets of 5 % and 3 % chloride contaminated SCC at the two ends were prepared respectively and the middle portion of these specimens was cast after 24 hours with uncontaminated SCC simulating the actual patch repair in the field; repaired due to chloride induced corrosion. From the six months experiment results of corrosion potentials and corrosion rates, it was found that the specimen having no chloride content at the middle portion showed high cathodic reactions and both chloride contaminated sides of the specimens showed even more corrosion than before being repaired due to the separation of anode and cathode and development of a macro-cell. This research has practical implications that need to be considered for an effective and durable repair of SCC structures