This past summer, Infrasense surveyed a bridge deck in La Crosse, Wisconsin using infrared for deck delamination detection according to ASTM D 4788 – 03. The equipment setup involved a dedicated vehicle mounted with a high resolution, distance triggered FLIR infrared camera synced up with a high-resolution visual spectrum camera. Both devices capture a whole lane width with each pass. Each pass was conducted at driving speed, with no disruption to traffic, and the 70-80-degree (F) temperatures made for a textbook day of surveying with outstanding data quality.
Textbook day of surveying with outstanding data quality
After collection, Infrasense also analyzed the data. The infrared data is reviewed simultaneously with the video data to identify delaminated areas vs. surface features; such as oil stains, sand, or debris. The white, blotchy areas that appear in the infrared data have a relatively higher temperature than their surroundings. This differential heating reveals a thermal barrier produced by a subsurface planar void, or delamination.
The client was provided with a table of quantities including the total area of delaminations, patched areas, and spalls. This same information was also provided in a digital plan view condition map, where the locations of each feature were mapped out.
High Resolution Video (left) and Infrared (right) comparison showing subsurface delamination