Experimental design on corrosion behavior of steel in submerged floating tunnels

Abstract

Corrosion of steel in concrete structures occurs because of depassivation by carbonation or chloride penetration. The corrosive products are expansive, and this causes cracking and deterioration of the concrete structures. So far, researches on the corrosion of steel in concrete structures have focused on the coastal structures such as bridges and harbor. Therefore, previous research provides insufficient data to understand corrosion behavior of submerged floating tunnels (SFT) in underwater environments. The corrosion of steel in the SFT can occur near internal and external surfaces of the structure where corrosive ions easily penetrate. In the external surface, penetration of the corrosive ions into concrete by high-pressure water should be considered while high concentration of CO2 is a main factor to induce the corrosion of steel in the internal surface. The purpose of this study is to design experiments to analyze the tendency of steel corrosion and penetration of corrosion factors of the SFT. The experimental results of this research are expected to be used as basic data to prevent deterioration of the SFT due to the corrosion of steel.