Improving Fracture Resistance Measurement in Asphalt Binder Specification with Verification on Asphalt Mixtures Cracking

The current performance grading (PG) specification for asphalt binders was developed during the Strategic Highway Research Program (SHRP), it is based primarily on the study of unmodified asphalt binders. Over the years experience has proven that the PG grading system, while good for ensuring overall quality, fails in some cases to guarantee good rutting and cracking performance, particularly as it applies to modified binders. Specifically, recent studies on mixes with highly modified binders from out of state (Minnesota) found that the MnRoad mixes have substantially improved cold weather cracking properties than mixes currently used in Texas, while still passing Texas Department of Transportation's (TxDOT's) Hamburg rutting requirements. To eliminate this type of apparent discrepancy AASHTO has adopted a new PG grading system based on the Multiple Stress Creep and Recovery (MSCR) test which is claimed to encourage the adoption of binders which are softer but still retain the required rut resistant. The benefits of the new grading system have not been verified for Texas asphalt binders and mixes. The major objectives of project 0-6674 are: (1) Determine if the new AASHTO MSCR-based binder grading system is superior to the current TxDOT binder grading system; (2) Identify/develop a simple test method or methods to characterize fracture and adhesive properties of asphalt binders and associated tentative specification limits; (3) Determine if the asphalt binders not currently used in Texas would potentially improve overlay performance, if so conduct an associated cost-benefit analysis; (4) Identify optimal asphalt binder/aggregate combinations for different environmental zones in Texas; (5) Develop and initially populate a catalogue of all these measured (binder, binder/fine aggregate mastic, and asphalt mix) properties with relevant information that can be used to track the field performance of pavements constructed using these asphalt binders.

Language

  • English

Project

  • Status: Completed
  • Funding: $221937.00
  • Contract Numbers:

    DTRT12-G-UTC06

    0-6674

  • Sponsor Organizations:

    Research and Innovative Technology Administration

    University Transportation Centers Program
    1200 New Jersey Avenue
    Washington, DC  United States  20590
  • Project Managers:

    Jensen, Darrin

    Peterson, Gerald

  • Performing Organizations:

    Texas A&M Transportation Institute, College Station

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

    Zhou, Fujie

  • Start Date: 20110901
  • Expected Completion Date: 0
  • Actual Completion Date: 20140831
  • Source Data: RiP Project 30003

Subject/Index Terms

Filing Info

  • Accession Number: 01568913
  • Record Type: Research project
  • Source Agency: Texas Department of Transportation
  • Contract Numbers: DTRT12-G-UTC06, 0-6674
  • Files: UTC, RiP
  • Created Date: Jun 30 2015 1:02AM