Distress Manifestation in Asphalt Pavements: Comparison between Local and Unmanned Aerial Vehicle (UAV) Measurements

Abstract

Surface surveys of asphalt concrete pavement condition the maintenance and rehabilitation solutions employed; however, they are laborious protocols for field operators. The use of Unmanned Aerial Vehicles (UAVs) in the remote assessment of these pavements has become an alternative, but still lacks validation about current Brazilian regulations. This study sought to compare conventional surface assessment methods (DNIT 006/2003-PRO, DNIT 007/2003 – PRO, and DNIT 433/2021-PRO) with the survey carried out by UAV, and to compare the DNIT’s cracked area assessment methods. The assessment was carried out over two 400-meter stretches. The DNIT 433/2021-PRO standard was more conservative than the DNIT 007/2003-PRO protocol in determining the cracked area. In addition, the two segments result in the same Global Gravity Index (GGI) classification between the walking and UAV methods only when rutting is disregarded. It was also found that the device achieved, on average, 82% of the cracked area values obtained by the DNIT 007/2003-PRO and DNIT 433/2021-PRO standards. Thus, it was possible to verify that the Brazilian regulations generate different cracked area results, being used for other purposes and that the UAV, in the scope of this work, the UAV was a technically viable alternative for speeding up the evaluations but was unable to identify cracks with smaller openings (FC-1 class) and three-dimensional distresses.