Cathodic protection of historical metal-hulled shipwrecks: A complementary approach from on-site global measurements to multiscale characterization (corrosion layers, biodiversity, and electrochemical measurements)
Résumé
Thousands of metal wrecks lie along the French coast, serving as tangible reminders of the two world conflicts. Over time, these contemporary wrecks have gradually formed artificial reefs. However, they deteriorate under the effect of corrosion, leading to the loss of valuable historical information and the potential release of polluting compounds and metals. This evolution of shipwrecks has drastic consequences for marine ecosystems and environment. To preserve these submerged structures and prevent their complete degradation, the French ANR project Save Our Shipwrecks (SOS) proposes to implement cathodic protection treatments on pilot wrecks in the English Channel and in Mediterranean. While cathodic protection is well-mastered for uncorroded metals, its application to heavily corroded submerged structures presents significant scientific and technical challenges. The SOS project is developing a new methodology by studying two shipwrecks located in different environments (e.g., geographical, depth). The wrecks are investigated comprehensively—from their metallic core to corrosion and concretion layers—as well as in relation to their surrounding environments, including sediments and biodiversity, both with and without the application of cathodic protection.