Inspection Methods and Techniques to Determine Non Visible Corrosion of Prestressing Strands in Concrete Bridge Components. Task 2: Assessment of Candidate NDT Methods

摘要

After several catastrophic failures of adjacent prestressed precast box beam bridges due to corrosion of the prestressing steel a research program was initiated by the Pennsylvania Department of Transportation. The goal of the research program is to examine if viable non-destructive testing methods for assessment of non-visible corrosion exist. Six commercially available techniques were assessed for accuracy in location on-visible corrosion damage. These testing methods were used on seven prestressed concrete box beams removed from three different decommissioned bridges in the state of Pennsylvania. The report compares the various testing methods and discusses the accuracy of each method in identifying corrosion of prestressing steel within the precast concrete beams.