Infrared Thermography As A Nondestructive Evaluation Technique For Fiber Composite Bridge Decks

The purpose of this research was to determine the optimal usage of Infrared Thermography (IRT) as a Non-Destructive Evaluation (NDE) method on glass fiber composite bridge decks. For various reasons, fiber bridge decks are a potential for replacing traditional steel-grate or concrete bridge decking. However, the main problem with fiber decks is that there is no proven NDE method. Two decks were tested: one that had been loaded to failure, and another that was undamaged. External heat was applied through the use of 8 halogen lamps arrayed around the outside, while an FLIR A320 ThermoVision infrared camera was set up to view the samples. The proximity of the lamps to the deck, the proximity of the camera to the deck, and the angle of the lights were all varied over the course of the testing, as well as different surface preparations from sanding to painting. The data itself was processed using both a sinusoidal fit as well as a logarithmic fit as an attempt to remove irregularities from the data. In the end, IR reflection from the lamps proved to be too much of an impact, and further testing needs to be done to mitigate this impact