Corrosion of reinforcing steel is recognized as the predominant cause of bridge deck deterioration. The need for a more precise method to estimate the susceptibility of a bridge to corrosion led to the development of the rapid chloride permeability test (AASHTO T 277-89 and ASTM C 1202-91). The developers of the test describe its conception, development, and applications. Concepts of permeability as applied to concrete are discussed, and the need for a rapid measure of chloride ion penetration into concrete is addressed. The authors describe the development and testing of a field method based on forcing chloride ions to migrate toward reinforcing steel maintained at apositive potential and note its limitations. Concurrent developmentof a laboratory procedure based on similar principles is described, and results of a round-robin statistical evaluation of method precision are presented. Further evaluations, current applications, and limitations are also discussed.
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