Bridges are very efficient traffic projects, usually to overcome terrain obstacles, and the foundation piles of bridges are reinforced concrete structures, just like the principles of modern building construction.
However, in the marine environment, the characteristics of high humidity and high salinity have a strong corrosive effect on all kinds of marine construction projects. The sodium and chloride ions in seawater will continue to act on the inside of the concrete to produce crystallization. Over time, these crystals grow and cause them to crack and fall off, exposing the internal steel structure. If the steel bar is corroded, it will twist or even break, and it will not be able to withstand the supporting strength and pressure. Obviously, this is a catastrophe for the sea-crossing bridge. A bridge that can be used on land for more than 50 years can corrode to the point of being unusable in just a few years if it is built in the sea.
Therefore, how to prevent corrosion of sea-crossing bridges is an important part of maintaining their life cycle. Fortunately, we have developed cathodic protection technology based on electrochemical principles. Cathodic protection can continuously give the bridge a protective current through the anode material and the impressed current. This current penetrates the concrete and acts directly on the internal reinforcement. The reinforcement is constantly replenished with electrons to protect it from the attack of sodium and chloride ions in seawater. As long as the structure that supports the strength and pressure is intact, the overall structure will not collapse. The service life of the bridge has been realized for decades, if not hundreds of years.