2005 Volume 54 Issue 4 Pages 158-163
This paper describes results of examinations to investigate the influence of tidal zone environment on cathodic current density for cathodically protected marine steel structure. Cathodic polarization at a fixed potential was conducted in the simulated tidal zone condition with the alternate exposure to air and 3%NaCl solution in which concentration of dissolved oxygen changed periodically. Consequently, the following results were obtained. Cathodic current density was maximum, immediately after rusted carbon steel was immersed in the solution. The maximum cathodic current density of rusted carbon steel was 1.00A/m2 or more, which was about 6 times more than that of bare carbon steel, and about 60 times more than that of carbon steel covered with calcareous deposits.