Condition Evaluation of Maine Turnpike Bridge Decks
In 2015 Infrasense performed ground penetrating radar (GPR), infrared thermography (IR), and high resolution video surveys to evaluate the condition of 7 bridge decks on the Maine Turnpike. These bridges represent nearly 46,975 square feet along I-95, and all had an asphalt overlay that severely limits the effectiveness of traditional sounding techniques. The GPR surveys were carried out at driving speeds, so no closures were required and traffic flow was not disrupted.
The GPR and IR surveys provide a deterioration quantity and map for each reinforced concrete bridge. The GPR surveys also produced rebar depth and asphalt thickness contour maps for each bridge deck. HNTB will utilize the deck condition results to plan future rehabilitation work on the Maine Turnpike. Infrasense had previously scanned 27 other Maine Turnpike bridge decks, representing over 250,000 square feet, using GPR.