Are PG 64E Binders Your Father’s PG 76?

This article briefly reviews the history of performance-graded (PG) binder specifications and the test methods used to evaluate these binders. The PG specification was modified to include a multiple stress creep recovery (MSCR) test, partially in response to an increase in the use of polymer-modified binders. The author reviews specifications that were in place in 2013 in the northeastern U.S. states (AASHTO M332), now that they have had five years of use in the real-world setting. The author reports on a study of seven different binder blends provided by six binder suppliers to determine if these binders meet the high-temperature requirements of AASHTO M320, if they contain the same amount of elastomeric polymer as in the past, and if there are any adjustments needed to the elastic response curve to ensure polymer dosage. The study found that seven of the E-grade blends did not quite meet a true PG high-temperature grade. The article includes figures and graphs of the study results. The author concludes that slight reductions in the grades for current binders have not resulted in field performance issues (e.g., rutting) in the northeast.

Language

  • English

Media Info

  • Media Type: Print
  • Features: Figures;
  • Pagination: pp 15-18
  • Serial:
    • Asphalt
    • Volume: 33
    • Issue Number: 3
    • Publisher: Asphalt Institute
    • ISSN: 0004-4954

Subject/Index Terms

Filing Info

  • Accession Number: 01691151
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Jan 20 2019 5:51PM