Comparing Performance of Full-depth Asphalt Pavements and Aggregate Base Pavements in NC

The North Carolina Department of Transportation (NCDOT) has a long history of building aggregate base pavements and, in recent years, has built full-depth asphalt pavements more frequently. The NCDOT assumes that the aggregate base pavements and full-depth asphalt pavements have the same length of service life and require the same maintenance and rehabilitation (M&R) treatments. However, different distress mechanisms in the aggregate base and full-depth pavements question the validity of these assumptions. If the performance of these two pavement types differs significantly, then the questions to be asked are related to the proper types of M&R treatment that are required, as well as to the appropriate time to apply such treatments. Research is urgently needed to answer these important questions. The answers to these questions are closely related to the NCDOT's ability to predict the performance of these two pavement types using its pavement design software, i.e., AASHTOWare Pavement Mechanistic Empirical (ME) Design (hereinafter called ME Design for brevity). It is expected that new top-down cracking and reflective cracking models will be implemented into ME Design in the next few years, and these new models will require the recalibration of ME Design for local conditions and materials. Efforts to address the performance differences between aggregate base and full-depth pavements can be undertaken such that the resulting data can support the future recalibration of ME Design. The objectives of the proposed research are: (1) to provide important performance information regarding asphalt base and aggregate base pavements that can be used to update the NCDOT's life cycle cost analysis (LCCA) procedure, (2) to identify pavement sections that have both base types in order to recalibrate ME Design for North Carolina conditions, and (3) to develop guidelines for the recalibration of ME Design and demonstrate the data collection process using new paving projects. The previous experience of and the databases possessed by the North Carolina State University (NCSU) research team from the NCDOT project Comparative Performance of Pavements and more recent projects on the local calibration of ME Design for hot-mix asphalt and warm-mix asphalt mixtures will be vital to accomplish these objectives successfully and to ensure the consistency within the master database to be developed in the proposed study. One of the products of this research is to determine the typical time at which the appropriate M&R treatment should be applied, referred to as time to treatment, for both base types for various climate and traffic loadings. The two base types also will be compared in terms of performance to test the existing LCCA assumptions. A second product of this study will be to determine candidate test sections for which data are sufficient to allow their use in the recalibration of ME Design. Because recalibration is required whenever models for the software are added or changed, this product will improve the efficiency of the recalibration process. The results of the time to treatment and performance comparisons for the two base types will be used in updating the NCDOT's LCCA procedure and to validate or disprove assumptions that the NCDOT has used up to this time. The test section selection process will allow pavement designers to select sections more easily for future calibration and recalibration. The pavement type selection and bid adjustments are based on LCCA procedures. Therefore, this research will provide data to support and improve the NCDOT's current LCCA procedure.


  • English


  • Status: Active
  • Contract Numbers:


  • Sponsor Organizations:

    North Carolina Department of Transportation

    Research and Development
    1549 Mail Service Center
    Raleigh, NC  United States  27699-1549
  • Project Managers:

    Kadibhai, Mustansir

  • Performing Organizations:

    North Carolina State University, Raleigh

    Department of Civil Engineering, Campus Box 7908
    Raleigh, NC  United States  27695-7908
  • Principal Investigators:

    Hintz, Cassie

    Kim, Y

  • Start Date: 20140816
  • Expected Completion Date: 0
  • Actual Completion Date: 20160815
  • Source Data: RiP Project 37088

Subject/Index Terms

Filing Info

  • Accession Number: 01536006
  • Record Type: Research project
  • Source Agency: North Carolina Department of Transportation
  • Contract Numbers: 2015-02
  • Files: RiP, STATEDOT
  • Created Date: Aug 28 2014 1:01AM