Corrosion behavior research and corrosion prediction of structural steel in marine engineering

Purpose This paper aims to reveal the corrosion mechanism and corrosion development regulation of marine engineering structural steel in the marine environment and provide constructive suggestions for marine immersed tunnel engineering. Design/methodology/approach In this study, marine engineering structural steel’s behavior and corrosion prediction were carried out under the conditions of no cathodic protection and under-protection by artificially adding dissolved oxygen in a simulated seawater solution as a depolarizing agent. Findings Marine resources are rich in China. With the development of the economy and the improvement of engineering technology, marine engineering structural steel is used more and more widely. Engineering structural steel has a great risk of corrosion failure for long-term service in seawater, as seawater is a kind of corrosive medium containing various salts. At present, there are few projects and research studies available on the corrosion in the seawater environment of Q390C engineering structural steel, which is used in the Shenzhen–Zhongshan Link immersed tunnel steel shell at home and abroad. It cannot guide the corrosion of immersed tunnel steel shells in the ocean. Originality/value In this paper, the corrosion mechanism and corrosion development regulation of marine engineering structural steel in the marine environment are studied by accelerated corrosion test in the laboratory, which is of great significance to ensure the long-life durability of the immersed tunnel in marine engineering.