Ontario’s First Experience with Regression Mix Design Method

This article describes the use of the Asphalt Mix Regression Mix Design Method as undertaken recently by the Ministry of Transportation Ontario (MTO). The author notes that many agencies across Canada and the U.S. have started to consider refinements to the traditional Superpave mix design procedure, with the goal of improving performance, especially the cracking resistance of asphalt mixtures. In the mix design method used in Ontario, the asphalt binder content is reduced from the standard 4.0% air voids to 3.5% air voids during production. In 2019, the MTO used this method on five paving projects across Ontario. The road crews found that it was easier to achieve compaction due to better workability of the mix from the additional asphalt. There were no sublots rejected because of low air voids, nor problems with bleeding or flushing. The MTO has planned at least 3 projects in 2020 that use this new strategy.

  • Authors:
    • Wakefield, Amma
    • Tabib, Seyed
  • Publication Date: 2020


  • English

Media Info

  • Media Type: Print
  • Features: Figures;
  • Pagination: pp 26-30
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 01758681
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Nov 15 2020 2:32PM