Corrosion propagation in carbonated reinforced concrete structures

In carbonated reinforced concrete structures, cracking and spalling of concrete cover due to reinforcement corrosion are generally considered as the limiting state for the end of service life. The propagation of corrosion of steel bars in carbonated concrete is diffi-cult to measure on-field. Moreover, existing reinforced concrete structures are often characterized by different concrete cover thicknesses, thus the reinforcement corrosion must be evaluated at different depths. In this paper, the results of a study on the pos-sibility of estimating corrosion rate of reinforcing steel by monitoring concrete electrical resistivity at different depths are reported. Laboratory and on-field tests were carried out and new specific probes for measuring concrete electrical resistivity at different depths in the concrete cover were used. Results have shown that the residual service life of carbonated reinforced concrete structure can be estimated by monitoring of concrete electrical resistivity.