Other title: Investigate feasibility of Ground Penetrating Radar to measure in-place density of new asphalt pavement

"February 2018."; "FHWA/OH-2017-28"--Technical report documentation page.; Includes bibliographical references (Final report, pages 45-45).; Final report.; Sponsoring agency: Ohio Department of Transportation, Office of Statewide Planning & Research; State Job No. 135158Final report (11 unnumbered pages, 45 pages) -- [Fact sheet]: Use Ground Penetrating Radar to quickly and non-destructively measure density on new asphalt pavements (2 unnumbered pages).Density of asphalt mixtures is one of the most important properties to monitor during construction of Hot Mix Asphalt (HMA) pavements. Many highway agencies routinely specify and measure in-situ asphalt mixture density or air void and use it as a basis for acceptance. Traditionally, density of a newly constructed asphalt concrete layer has been measured in the laboratory using randomly selected core samples extracted from finished pavement. This study investigates the applicability of Ground Penetrating Radar (GPR) for assessment of in-place density of HMA mixtures. GPR measurements were made at two ongoing construction projects in Ohio. Core samples were simultaneously collected and tested in the lab. An analytical model called the 'ALL model' proposed by the University of Illinois researchers was used to derive density values from GPR measurements. The analysis of data indicated that results from core samples and GPR measurements are statistically comparable. Based on the results obtained, it can be concluded that GPR has the potential to map the density of in-place asphalt mixtures in comparison with core densities