Abstract:
Chloride-induced corrosion of reinforcing steel bar is a major factor that affects structural performance of reinforced concrete structures. It is important to acculately calculate the corrosion loss of the reinforcing steel bar. A probability model for corrosion rate is developed in this paper, in which both the time of corrosion initiation and the time of concrete cover cracking are treated as random variables which are related to uncertainties in the process of reinforcing steel bar corrosion. Statistical analysis of the corrosion rate is conducted by Monte Carlo simulation and the statistical parameters and distribution type of the corrosion rate are determined. Finally, an expression to depict the relationship between the resistance of the RC flexual member and the corrosion rate of the reinforcing steel bar is proposed based on the collected experimental data in literatures, and time-dependent reliability analysis of corroded RC member served in marine environment is performed. The analysis results show that the corrosion rate loss of steel bar follows a bimodal probability distribution. The probabilities of having no corrosion and no cover cracking reduce with the time increasing. The reliability indexes reduce significantly with time due to chloride-induced corrosion.