Modified Binder (PG+) Specifications and Quality Control Criteria

Based on the stated needs and goals, the main objectives of the proposed pooled fund research include: (1) Perform detailed assessment of current PG+ and modified binder quality control procedures in partnering states in terms of reliability, applicability, and relevance to performance and quality of modified asphalt binders. (2) Use a range of modified binders, representative of the products currently specified by partner states, to develop unified test procedures and specification criteria based on products placed in the field. (3) Improve product quality and reliability through conduct of ruggedness studies and development of precision and bias statements for selected tests. (4) Introduce consistency to current products supplied by elimination or reduction of differences in modified binder acceptance tests and criteria throughout member states. (5) Validate and establish relevance of suggested PG+ and quality control procedures in terms of mixture performance. The pavement material research group at the University of Wisconsin Madison and the Modified Asphalt Research Center (MARC) under the directorship of Professor Hussain Bahia has had extensive experience evaluating, improving, and developing asphalt binder characterization methods and test procedures. Such efforts notably include the National Cooperative Highway Research Program (NCHRP) project 9-10 on design of asphalt mixtures using modified asphalt binders which led to the development of the repeated creep test which later became the basis for development of the Multiple Stress Creep and Recovery (MCSR) test. Through the Asphalt Research Consortium (ARC) project, the team has been involved in evaluating and validating existing modified binder testing procedures and development of standards /specification criteria. The project involved collaboration with the Western Cooperative Test Group (WCTG), the Rocky Mountain Asphalt User-Produce Group (RMAUPG), state highway agencies and industry to improve PG+ specifications currently in use through documentation of benefits and costs associated with these tests, development of protocols for new binder tests, and development of specification criteria for new tests based on field evaluation of construction and performance. Additionally, interviews and surveys for soliciting feedback on binder tests and specifications were conducted among a large number of state highway agencies as part of this effort. As part of ARC, MARC has also been involved in validating newly developed asphalt binder procedures using comparison with field performance of Long-Term Pavement Performance (LTPP) and MnROAD test sections. As part of MARC's involvement in regional modified binder specifications, the group completed Phase 1 of the Wisconsin Department of Transportation (WisDOT) project for development of "Modified Asphalt Binder Guidelines" and is currently the principal on a follow up study intended to identify test methods and specification limits based on field performance measurements from modified asphalt pavement sections constructed in the early 2000s across Wisconsin.


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Filing Info

  • Accession Number: 01570475
  • Record Type: Research project
  • Source Agency: Federal Highway Administration
  • Contract Numbers: TPF-5(302)
  • Created Date: Jul 22 2015 1:01AM