Corrosion Rate Determination on Repaired Reinforced Concrete Specimens

The repair and maintenance of reinforced concrete structures is becoming increasingly important as structures become older and the use of condition surveys becomes more extensive. Although guidelines exist for repair methods, little is known about the corrosion behavior once repairs are made. In this investigation, electrochemical tests typically used on reinforced concrete specimens were used on repaired specimens which were subjected to wet (3.5% sodium chloride (NaCl) solution) and dry cycling. Repaired specimens made with a water/cement ratio of 0.6 and patched with a common repair material showed rust staining, severe delamination, and cracking after a number of cycles while the typical (control) samples did not. Although both types of specimens had comparable corrosion potentials, linear polarization measurements showed that Rp was lower, and therefore corrosion rates in the repaired specimens were higher than in the control specimens.