Infrared thermographic bridge deck inspection on the Poplar Street Bridge, St. Louis, Missouri: Fid-Bau Portal

Infrared thermographic bridge deck inspection on the Poplar Street Bridge, St. Louis, Missouri

Fuchs, P.A. / Washer, G.A.

The Federal Highway Administration (FHWA) Nondestructive Evaluation (NDE) Center has been developing an infrared (IR) thermographic system designed to inspect bridge decks in a rapid and efficient manner. The system is primarily intended for bare concrete decks and for the assessment of thin wearing surfaces on bridge decks. Recently the Missouri Department of Transportation (MoDOT) requested the use of the NDE Center IR System in order to examine the wearing surface on the Poplar Street Bridge in St. Louis, Missouri. The NDE Center IR system was used because the Poplar Street Bridge is very large and carries a significant amount of traffic. Lane closure at this bridge site is difficult and data must be collected with minimal disruption to traffic. The NDE Center IR system collected data on the entire Poplar Street Bridge deck without requiring a lane closure. This structure has 8 lanes of traffic with a total span length of about 670 m (2200 ft). The NDE Center IR System was well suited to assess this type of bridge deck on the Poplar Street Bridge as this structure has a 15.9 min (5/8 in.) thick steel orthotropic deck with a 12.7 mm (1/2 in.) thick, low-modulus epoxy concrete overlay. The NDE Center IR system is a prototype and this field test is the first large-scale application of the device. The goal of the testing was to identify and locate potential defect areas in the wearing surface on the bridge deck. This paper discusses the results of testing on the Poplar Street Bridge, St. Louis, Missouri.