Nondestructive Testing and Evaluation of Reinforced Concrete Bridge Decks: A Case Study.

This paper describes a thorough investigation of two bridge decks using ground penetrating radar (GPR), infrared thermography (IR), chain drag, crack mapping, coring, and chloride ion concentration measurements. It discusses the use of GPR for the detection of bridge deck flaws at the reinforcing steel level and the use of IR for the identification of overlay delamination. The GPR and IR results are compared to the results obtained from sounding the bridge decks. The correlation between the damages detected using GPR and IR and the conventional chain drag technique is discussed. Combined together, the nondestructive methods used in this study complemented each other to provide the maximum amount of information and create a more effective bridge deck condition assessment. Infrared thermography was effective in the detection of shallow delamination. Ground penetrating radar detected damage at the rebar level and damage extending upward from the corroding rebar to about 2.5 cm from the deck surface. Unlike chain drag, which detects discontinuities in advanced stages, GPR detected features associated with rebar corrosion, such as highmoisture content and high chloride ion concentrations, in early stages. A comprehensive rehabilitation approach of the two structures is proposed. [ABSTRACT FROM AUTHOR]