Roadway Structure and Condition Evaluations on I-17 in Arizona

In the Fall of 2019, Infrasense headed out to the desert for a pavement evaluation of 29 miles of Interstate 17 outside of Flagstaff, Arizona. The objectives of this evaluation were to identify the pavement structure and to locate and quantify deterioration of the pavement surface, subsurface, and joints. In order to provide this information, Infrasense deployed a ground penetrating radar system with a range of antenna frequencies, and a high-resolution visual data system capable of asphalt spalling and cracking. All data was collected synchronously with GPS coordinates in order to accurately locate the detected pavement conditions.

The GPR data was collected using 4 different frequencies of antenna, each one providing a unique level of resolution and depth. The air-launched 1GHz and 2GHz antennas were used at normal driving speeds in order to characterize the pavement structure and evaluate the near-surface condition. Conversely, the ground-coupled 900MHz and 400MHz antennas were deployed at lower speeds and higher scan densities in order to collect detailed condition information at the pavement joints and identify the pavement base and sub-base structure. This data was collected using a rolling closure to minimize disruption to normal traffic flow.