2018 Volume 74 Issue 3 Pages 192-206
Cathodic protection is a highly reliable corrosion protection method for re-bar in concrete. Generally, “100-mV Polarization Shift or Depolarization Shift” is used as a criterion of cathodic protection for rein-forcing steel in concrete.
In this study, we examined the relationship between potential shift values and effect of cathodic protection, using concrete specimens in which small, electrically-connected steel splits were embedded. As the result, we found that the corrosion rate can be reduced by the cathodic protection applied in the range of less than 100-mV polarization shift. However, from the point of view to stop the corrosion reaction electrochemically, we concluded that 100-mV polarization shift is appropriate as the criterion.
Furthermore, we proposed a method of supplying protection current, the installation position of a reference electrodes, and the design method of criterion of cathodic protection for corrosion rate.
