Evaluation of the Rolling Density Meter for Rapid Continuous Measurement of Asphalt Mixture Density

The rolling-density meter (RDM) is a ground-penetrating radar (GPR)-based system tailored for rapidly and continuously measuring asphalt mixture density. This research analyzed the readiness level of the RDM and provided recommendations for how this technology could be used in quality control/quality assurance (QC/QA). To evaluate the RDM precision, four antennas were used in a laboratory environment to test six different materials. Increasing the number of scans averaged did improve the precision. For materials similar to those tested, the dielectric measurement was repeatable within 0.15 and reproducible within 0.22 or better. The RDM was deployed on six field projects for multiple paving days. Researchers evaluated the reproducibility of calibration curves, precision and bias of the system and of a nuclear density gage, and distribution of predicted air voids. Overall air void calibrations were good with an average R² value of 0.76. The calibration curves were unique for different paving projects, and in some cases unique for different days of paving. Using different antennas for calibration did not influence the resulting calibration curves. The RDM was more precise than the nuclear density gauge and unbiased. The field data were used to perform a producer and consumer risk analysis. Different pay factors and percent within limit characterizations were calculated. The single-core acceptance method exposes producers and consumers to significant risk while density profiling with the RDM effectively eliminates risk. An alternative 3D radar system was deployed on three test sections. The system produced high resolution scans of the asphalt surface and subsurface. Further work is needed to tailor data processing for density testing. Researchers recommend adopting the draft test method and equipment specifications for rapid full-coverage measurements of asphalt mixture density using GPR.

• Record URL:
  https://static.tti.tamu.edu/tti.tamu.edu/documents/0-6889-R1.pdf
• 
• Summary URL:
  https://library.ctr.utexas.edu/Presto/catalogid=36698
• Summary URL:
  https://rosap.ntl.bts.gov/view/dot/66055
• Record URL:
  https://rosap.ntl.bts.gov/view/dot/61486
• Supplemental Notes:
  • Project Title: Rolling Density Meter to Ensure Long Term Performance of Flexible Pavements.
• Corporate Authors:

  Texas A&M Transportation Institute

  Texas A&M University System
  3135 TAMU
  College Station, TX  United States  77843-3135

  Texas Department of Transportation

  Research and Technology Implementation Office
  125 E 11th Street
  Austin, TX  United States  78701-2483

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Wilson, Bryan
  • Sebesta, Stephen
  • Scullion, Tom
• Publication Date: 2019-1

Language

• English

Media Info

• Media Type: Digital/other
• Edition: Technical Report
• Features: Appendices; Figures; Maps; Photos; References; Tables;
• Pagination: 96p

Subject/Index Terms

• TRT Terms: Air voids; Alternatives analysis; Asphalt mixtures; Calibration; Density; Evaluation and assessment; Field tests; Ground penetrating radar; Laboratory tests; Quality assurance; Quality control; Risk analysis; Test procedures
• Subject Areas: Construction; Highways; Pavements;

Filing Info

• Accession Number: 01692006
• Record Type: Publication
• Report/Paper Numbers: FHWA/TX-17/0-6889-R1, 0-6889-R1
• Contract Numbers: 0-6889
• Files: NTL, TRIS, ATRI, USDOT, STATEDOT
• Created Date: Jan 31 2019 5:17PM