It is well known that corrosion of reinforcement leading to concrete deck delaminations is a major maintenance repair replacement cost for state DOT’s across the country. Accurate mapping of top and bottom delaminations is needed to guide repair replacement decisions. The inspection of concrete bridge decks typically includes a delamination survey (with chain dragging for acoustic sounding that detects top rebar delaminations only). Employing innovative scanning NDE systems can improve delamination mapping accuracy, reduce inspection time, and provide additional information regarding possible bottom delaminations, the internal concrete conditions. In addition, sophisticated NDE systems can be employed in instances in which traditional chain dragging techniques have not been effective, such as on asphalt overlain concrete bridge decks. A research project titled “Vehicle-Mounted Bridge Deck Scanner” funded by the NCHRP-IDEA program is summarized herein. This research project focused on the development of rapid inspection techniques by adapting well known NDE test methods into rolling scanning equipment. The equipment then allowed for rapid testing to provide: (1) top and bottom delamination mapping; (2) internal conditions deterioration mapping; and (3) thickness profiling. Since development of the system, multiple bridge decks of varying type and condition have been evaluated. Three case studies, in which, comparison ground-truth techniques (Sounding, Coring, GPR, etc.) were employed, are presented herein. The presented case studies include both concrete and asphalt covered bridge decks.

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