Laboratory performance of warm mix asphalt with high RAP content

Road construction using warm-mix asphalt (WMA) has been rapidly gaining popularity in the United States. The number of WMA projects constructed has grown aggressively and steadily. Parallel to this rapid growth in WMA construction is the attention placed on usage of high percent of reclaimed asphalt pavement (RAP) in asphalt construction. A laboratory investigation took place on the behavior of high RAP mixes with three WMA technologies: water foaming, a chemical additive, and an organic additive. The work included mix design, moisture damage evaluation, and rutting evaluation using the Indirect Tensile Tester, Superpave Shear Tester (SST) and Model Mobile Load Simulator Third Scale (MMLS3). This research indicates that it is possible to produce WMA with sufficient moisture damage and rutting resistance. However, a mix design established for hot mix asphalt (HMA) does not necessarily produce satisfactory performance when used with WMA, and it is important that moisture damage and rutting susceptibility of WMA be evaluated for any mix design even though that mix design might have demonstrated satisfactory performance for HMA. Optimum binder content developed from HMA could be applied to WMA but air void must be checked for WMA at the design number of gyrations to ensure it does not differ significantly from the HMA design air void. A difference in air void of no more than ±0.75 percent is recommended. Larger differences in air void require adjustments to the binder content.


  • English

Media Info

  • Pagination: 9p
  • Monograph Title: 11th Conference on Asphalt Pavements for Southern Africa: CAPSA15, 16-19 August 2015, Sun City, South Africa

Subject/Index Terms

Filing Info

  • Accession Number: 01597104
  • Record Type: Publication
  • Source Agency: ARRB
  • Files: ATRI
  • Created Date: Apr 22 2016 11:14AM