An Experimental Study on the Effects of Oxygen and Moisture Transport Control on Steel Corrosion in Reinforced Concrete Structures

In this study, the effects of suppressing oxygen and moisture diffusion through the application of surface finishing materials on the initiation and progression of steel corrosion in concrete were comparatively evaluated. To this end, the type of binder and the chloride ion content were selected as the main variables, and the corrosion behavior of embedded steel was analyzed using the Half-Cell Potential Method, which enables quantitative assessment of electrochemical changes during the early stage of corrosion. Through this approach, the study aimed to provide fundamental data for establishing rational criteria for the intrinsic chloride ion content in cement. The results showed that the incorporation of ground granulated blast-furnace slag and the application of a coating were effective in delaying or reducing steel corrosion through chloride ion immobilization and the suppression of oxygen and moisture diffusion, respectively. However, under the condition of using ordinary Portland cement (OPC) alone, the likelihood of corrosion was found to increase significantly when the chloride ion content exceeded the critical threshold.