Automated temperature profiling during hot-mix asphalt construction

The prototype infrared sensor bar originally developed for NCHRP-IDEA Project 73 was adapted and used for monitoring temperature profiles during the reconstruction of selected test track sections at the Auburn University National Center for Asphalt Technology. The sensor bar provides automatic temperature data collection across the back of the paver. The unit, and all electronics, can be mounted on the paver in less than 2 min. Results from the sensor bar correlate well with handheld infrared gun data once an offset to calibrate the sensor bar readings is applied. Sensor bar temperature measurements can accurately predict the hot-mix asphalt cooling curve theoretically predicted from the PaveCool software program. Temperature contour plots can be obtained easily from the temperature data automatically collected during construction. These contour maps can be used to identify the start of paving, the consistency of the operation, and the length of time of any stops.