Investigate Feasibility of GPR to Measure In-Place Density of New Asphalt Pavement

Investigate Feasibility of ground penetrating radar (GPR) to Measure In-Place Density of New Asphalt Pavement Density of asphalt mixtures is one of the most important properties to monitor during construction of hot mix asphalt pavements. Density is deemed important in asphalt pavement construction since it influences the void structure of the asphalt mixture. When the air voids are lower than a specified value, the constructed pavements will experience rutting, shoving and bleeding due to plastic flow. When the air voids are higher than a specified value, the mixture will allow water and air to permeate into the structure resulting in water damage, oxidation, raveling and cracking. Since density of an asphalt mixture varies throughout its life, the voids also vary proportionally. The voids must be low enough initially to prevent permeability of air and water and high enough after a few years of traffic to prevent plastic flow. Traditionally, density has been measured in the laboratory using core samples. However, cores provide data at only a limited number of random locations. Some organizations supplement cores with data from a nuclear or electrical density gauge. The Ohio Department of Transportation (ODT) requires the contractors obtain cores to determine in-place density of the compacted mixture as a percentage of the average QC Maximum Specific Gravity (MSG) for the production day the material was placed. In Ohio, data from the cores are used to calibrate the electrical density gauge. At the end of the job, the department marks ten locations for taking core samples. The core samples are tested by the State to verify density of compacted asphalt mixture. Extensive research completed in Finland in the late 1990s verified the ability to measure asphalt air void content with GPR. The air void values were obtained from GPR-based dielectric measurements using a small number of cores for calibration. The researcher's objectives and goals include documenting GPR technology as applied to measurement of asphalt mixture in-place density, design and develop a statistically valid field and lab experiment, compare GPR data with results from cores and electric gauge, process the data and generate information that can assist ODOT to develop quality control/quality assurance (QC/QA) specifications for acceptance of the compacted asphalt mixtures. Some of the benefits of this study are that GPR is non-destructive, it can provide rapid measurements with immediate results, compared to core sampling at isolated spots, data sampling can encompass up to 100 % of the paved area and the results can depict quality and uniformity of density through the project.

    Language

    • English

    Project

    • Status: Active
    • Funding: $45947.00
    • Contract Numbers:

      27097

      135158

    • Sponsor Organizations:

      Infrastructure Management and Engineering, Incorporated

      ,    
    • Project Managers:

      Landefeld, Craig

    • Principal Investigators:

      Rajagopal, Arudi

    • Start Date: 20150803
    • Expected Completion Date: 20170803
    • Actual Completion Date: 0
    • Source Data: RiP Project 40126

    Subject/Index Terms

    Filing Info

    • Accession Number: 01570571
    • Record Type: Research project
    • Source Agency: Ohio Department of Transportation
    • Contract Numbers: 27097, 135158
    • Files: RiP, STATEDOT
    • Created Date: Jul 24 2015 1:00AM