Time-Lapse Infrared Thermography Applied to Concrete Bridge Deck Inspection Surveys

The Federal Highway Administration mandates that all [bridge] structures in its inventory are to be inspected every two years. Consequently, deck surveys are conducted to identify unseen damage within them. A significant number of bridges in Virginia have concrete decks with an overlay. Methods commonly deployed on these decks, are limited in the quantitative results they can provide. To overcome these limitations, an improved method of applying infrared thermography using time-lapse technology is introduced. Following a simulated parametric study, a time-lapse infrared thermography data collection system was acquired along with a basic program to analyze the data qualitatively. A novel physics-based program was also developed to analyze the data quantitatively. The system is ready to be deployed on most bridges, offering a full-field non-contact survey of the entire deck with minimal impact to traffic flow. However, it is recommended that the quantitative program undergo additional testing prior to production level deployment. The full report can be downloaded from the Virginia DOT web site at http://www.virginiadot.org/vtrc/main/online_reports/pdf/20-R22.pdf