Uncertainty Modeling of Chloride Contamination and Corrosion of Concrete Bridges

7. Conclusions

This paper presented a reliability-based approach for the modeling of the deterioration and service life of concrete structures taking into account the uncertainties in the physical modeling, and variability of the material and structural parameters governing the chloride penetration into concrete and corrosion of the reinforcing steel. It illustrated the application of a probabilistic approach for the uncertainty modeling and prediction of chloride contamination of concrete and reinforcement corrosion in bridge structures that are subjected to the application of deicing salts during winter. The proposed probabilistic model provided very good predictions of the level of chloride contamination at different depths as well as the extent of corrosion of the reinforcing steel in the top mat of a deteriorated reinforced concrete bridge deck. The application of such an approach is required in the assessment of safety and serviceability of deteriorating concrete structures in order to ensure that the probability of failure is kept at an acceptable level. A reliability-based prediction of the service life of deteriorating concrete structures provides a rational decision support tool at both the initial design stage and during the operation and maintenance stage. The implementation of such an approach allows adequate control of the safety and serviceability of the structure throughout its service life and yields low life cycle cost.