Validation of ODOT’s LaserMacrotexture System

This paper investigates and compares mean profile depth (MPD) measurements from two laser-based macrotexture measuring devices, namely a laser profiler and an Ames Laser Texture Scanner, to mean texture depth (MTD) results from volumetric sand patch tests. In addition, the effects of speed and material type on the MPD results for the profiler were also researched. The study used data obtained from field testing at three sites, each with a variety of pavement types, and laboratory testing on various types of Hot Mix Asphalt (HMA) and Portland cement concrete samples of varying finish, as well as other common, manufactured, textured samples. Analysis of the data showed that the MPD obtained from the Ames Laser Texture Scanner had the highest correlation to the MTD measurements determined using the sand patch test. It was also determined that the MPD values taken by the laser profiler decreased as the speed at which the sample was traveling increased. A new correlation for predicting MTD from laser profiler MPD was developed through laboratory testing. Additionally, it was found that material type had an effect on the laser MPD values.