Review on Cathodic Protection for Marine Structures

Corrosion in harsh marine environment is a fatal factor influencing the performance and service life of a marine structure. Cathodic protection in combination with other methods like coating is a very effective way to mitigate the corrosion of metallic structures in sea water. According to the different ways of protective current,cathodic protection is divided into two methods,including sacrificial anode and impressed current cathodic protection. Sacrificial anode method is simple and reliable,but needs large amount of anode materials,and more accurate design. Impressed current cathodic protection method can realize the automatic control,making the protected structure always in the set range of potential by the automatic adjustment of current output. This review deals with the state-of-the-art of cathodic protection technology for marine engineering structures,including sacrificial anode materials and impressed current cathodic protection system for marine structures,the criteria of cathodic protection potential for alloyed steels with different strength,the cathodic protection monitoring as well as the development and application of the design method for optimization,especially,the numerical simulation design approach. Finally,the trend of development of cathodic protection for marine structures has been discussed.