Chloride-induced corrosion initiation and propagation in sound and micro-cracked concretes

In the durability design of reinforced concrtete structures exposed to chloride-bearing environ-ment the effect of cracks cannot be neglected. Literature agrees that cracks affect corrosion initia-tion time, while controversial results on propagation time are repotered. In this study corrosion was investigated in sound and longitudinally micro-cracked concrete samples reinforced with carbon steel bars, exposed to a NaCl solution for more than 2 years, and monitored with electro-chemical techniques. Results showed that corrosion initiation was affected by the presence of the micro-crack, above all when the crack was developed until rebar depth, while no particular effects were detected on corrosion propagation stage.