Chloride Penetration and the Deterioration of Concrete Bridge Decks

The rapid deterioration of the nation's bridges is a widely recognized problem. A major contributor to this problem is bridge deck deterioration caused by chloride-induced corrosion of reinforcement. Chlorides are derived primarily from the application of roadway deicing salts. This paper synthesizes empirical data from previous studies with the diffusion theory in developing a predictive model for chloride infusion of bridge decks. The model includes the effects of subsidence cracking over the reinforcement. Primary input data consist only of average reinforcement cover, which is easily obtainable with existing instrumentation. The model is intended to serve as a useful, rational means of providing information for life-cycle costing in bridge deck rehabilitation planning studies.