Current distribution in reinforced concrete cathodic protection system with conductive mortar overlay anode

The current distribution was studied in a designed three-layer reinforced concrete cathodic protection (CP) system, with carbon fibre reinforced cement (CFRC) as the conductive mortar overlay anode. The influence of steel bars’ initial corrosion state, concrete resistivity and magnitude of impressed current density on the current distribution was discussed, respectively. Testing results show that the initial corrosion rate of steel has a great effect on the protection current distribution. In addition, there exists a threshold for corrosion rate, beyond which the uniformity of protection current distribution worsens markedly. Higher concrete resistivity not only deteriorates the current distribution, but also has an adverse effect on the rebars far away from the anode. However, the magnitude of impressed current density only affects the uniformity of current distribution to some extent when the rebars are corroding. This study could be useful to the cathodic protection of reinforced concrete structures in field condition.