740 S Pierce Ave, Unit 15, Louisville, CO 80027
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Unmanned Vehicle Inspection of Bridge (NDE)

BDI performed a variety of inspection services including video inspection of each bent, detailed video of the beam bearings, aerial site map, bridge elevation images, deck thermal imaging, and chloride tests on several reinforced concrete (RC) components utilizing unmanned aerial vehicles and other specialized equipment. This work was performed on the vehicle bridge as well as the adjacent original bridge, which is now used as a pedestrian bridge. The goal of the project was to provide a complete set of images and concrete condition from which to access the overall bridge condition for long-term maintenance planning.

The bridge was approximately one mile long and was composed of 181 spans. Each span of the vehicle bridge consisted of 7 precast RC panels with 5 ribs, with 180 piers there were a total of 12,600 beam bearing pads. The time required to perform visual inspection and the disruption to traffic would have been excessive; therefore, drone-based video recording was the only practical approach.

Video was obtained from a combination of unmanned aerial vehicles (UAVs) and remote-controlled cameras mounted on poles. For the overall plan view, elevation view, and thermal imagining of the deck, incremental overlapping pictures taken were taken by UAVs flying the length of the bridge. These photographs were stitched together into single image files and provided with the raw video footage.

Concrete samples were taken at 15 locations on the roadway deck and at 15 locations on several pile caps. These samples were analyzed for chloride content.

Video quality was reduced for web