The 4th Asian Concrete Federation Symposium on Emerging Technologies for Structural Longevity (ACF2023- ETSL)

214 / 2022-06-07 19:04:37

Effect of Stress on Corrosion Behavior of Steel Bars Embedded in Concrete

Stress; Steel corrosion; Reinforced concrete structure; Chloride environment; Electrochemical model

In actual projects, concrete structures are often subjected to stress. Therefore, the corrosion characteristics of steel bars embedded in concrete exposed to harmful media in chloride salt environments require consideration of both the influence of applied stress on the chloride ion transport process as well as the electrochemical corrosion process. In this study, the influence law of stress on the internal mass transport of concrete was investigated, and the steel bars de-passivation behavior under the stress was analyzed through the indicators of critical chloride threshold and passivation film damage evolution. The results indicate that the decrease in critical chloride threshold can be attributed to the degradation of the passive film. Simultaneously, a multi-physical field coupling of mechanics-mass transfer-electrochemistry in the electrochemical model is also realized based on the quantitative relationship among the mass transport parameters of the concrete, the electrochemical parameters of the steel bars, and the structural mechanical characteristic parameters. The developed electrochemical model provides a technical means to predict the corrosion behavior of steel bars embedded in concrete in different environments.