Effect of dissolved oxygen on corrosion properties of reinforcing steel

A series of electrochemical experiments were conducted to investigate the effect of dissolved oxygen, pH and Cl− on the corrosion rate of reinforcing steel of geological disposal facility saturated with groundwater. It was found that the corrosion rate was proportional to the concentration of Cl− and dissolved oxygen which are known as a corrosive agent and an electron acceptor, respectively. The pH level also strongly influenced the corrosion rate of the reinforcing steel. Under the pore water conditions of concrete structure of geological disposal facility, i.e. pH of 10–12 and dissolved oxygen of 1 mg L−1, the corrosion rate of reinforcing steel was determined to be in the range of ∼10−8 to ∼10−9 m/year. The corrosion rates were higher than those estimated from an empirical model based on the diffusion of dissolved oxygen.