Identifying Influences on and Minimizing the Variability of Ignition Furnace Correction Factors

AASHTO T 308, Determining the Asphalt Binder Content of Hot Mix Asphalt (HMA) by the Ignition Method, requires determination of asphalt and aggregate correction factors for asphalt mix designs for each ignition furnace used to test a design. In some cases where there are numerous asphalt mix designs or numerous ignition furnaces testing a particular mix design, correction factors are shared between ignition furnaces, though this practice is not permitted by AASHTO T 308 without supporting evidence. There is a lack of knowledge of (1) how ignition furnace installation, operation, and maintenance influence correction factors and (2) ways to minimize differences that arise between ignition furnaces. Moreover, there is a lack of a statistically valid verification procedure to identify causes for non-comparing, statistically different, or biased test results from ignition furnaces. A verification procedure will promote consistency in results and assist in dispute resolution. The objectives of this research were to (1) determine the variability of asphalt and aggregate correction factors for asphalt mixes containing significant asphalt recycled materials compared to those with virgin binder and aggregate only; (2) further evaluate the effect of reducing the test temperature of AASHTO T 308 method to 800°F; and (3) conduct an interlaboratory study with different mixes to establish a new precision statement for the test procedure.


  • English


  • Status: Completed
  • Funding: $250000
  • Contract Numbers:

    Project 09-56A

  • Sponsor Organizations:

    National Cooperative Highway Research Program

    Transportation Research Board
    500 Fifth Street, NW
    Washington, DC  United States  20001

    Federal Highway Administration

    1200 New Jersey Avenue, SE
    Washington, DC  United States  20590

    American Association of State Highway and Transportation Officials (AASHTO)

    444 North Capitol Street, NW
    Washington, DC  United States  20001
  • Project Managers:

    Harrigan, Edward

  • Performing Organizations:

    National Center for Asphalt Technology

    277 Technology Pkwy
    Auburn, AL  United States  36830
  • Principal Investigators:

    Rodezno, Carolina

  • Start Date: 20170512
  • Expected Completion Date: 20211231
  • Actual Completion Date: 20211231

Subject/Index Terms

Filing Info

  • Accession Number: 01698958
  • Record Type: Research project
  • Source Agency: Transportation Research Board
  • Contract Numbers: Project 09-56A
  • Files: TRB, RIP
  • Created Date: Mar 18 2019 4:11PM