Infrared Thermography Technologies for Thermal Measurement and Control of HMA Pavement Construction

Infrared thermography technologies are rapidly developing for thermal measurement and control of hot mix asphalt (HMA) pavement and airfield construction. Two technologies currently used and/or specified include hand-held thermal imaging cameras for discrete measurement and paver-mounted temperature sensors for continuous measurement. A field evaluation of these new technologies was conducted on three asphalt paving projects by collecting thermal readings in the truck box, paver hopper, and behind the paver screed. Analysis of the field data concluded these technologies are capable of detecting HMA temperature variability during construction that can lead to process adjustments and other quality control actions. The HMA temperature ranged from 100°F to 160°F in the truck box, while material behind the screed ranged from 8°F to 53°F. The HMA temperature standard deviation behind the paver was reduced from 9.4°F to 5.5°F when a material transfer vehicle (MTV) was included in the paving operation. When a pass/fail criteria is set at a range of 25°F in a transverse section behind the screed, locations having a material transfer vehicle (MTV) are able to pass this requirement in 10 of 11 tests, while not having an MTV failed this requirement in 4 of 4 tests.