Study on retrofit design of port steel structures with cathodic protection of galvanic anode system

We investigated retrofit design in cathodic protection (CP) with galvanic anodes made from an aluminum alloy. In conventional retrofit design, the decrease in CP current reduction (which affects the life of anodes) is estimated based on nominal durability values. The current reduction rate falls to a level far below the design value, leading to an increased number of facilities in which the anode life exceeds the design service life. As this trend is due to exaggerated design, it is necessary to review retrofitting methods in order to enable more effective and economical maintenance. After detailed analysis and discussion, we developed an innovative methodology for an optimized maintenance system in galvanic anode CP. To test the assumptions made, we conducted on-site, shortterm testing with an actual structure and confirmed the validity of the new design methodology. The method, which takes current reduction into consideration, allowed more accurate prediction of anode life and a reduction in the initial costs of CP facilities.