Warm Mix Asphalt

Abstract and project information last updated: 9 July 2013. Project updates are dated below.

Construction equipment and crews in the left work to flatten an asphalt mixture, moving away from the viewer. Three people in orange safety vests stand alongside the road on the right side of the image. The road is tree-lined.

Credit: Peng Li

Construction crews work paving a field site in Petersberg, Alaska in September 2008 using sasobit-modified asphalt mixture.

Juanyu (Jenny) Liu (UAF)

US Department of Transportation (RITA)

Permafrost Technology Foundation

1 July 2008
End Date
1 May 2010



Field practices and studies including an on-going NCHRP and other state research projects showed that using warm mix asphalt (WMA) can reduce the high mixing temperatures of regular hot mix asphalt (HMA), increase the temperature gap between production and cessation (allowing increased haul distances), and decrease the binder viscosity allowing effective compaction, which is beneficial for stiff mixes, paving during extreme weather conditions and reduction in compaction effort.However, previous research has not focused much on how WMA functions in cold weather paving and the performance of the WMA in cold regions.

In line with the WMA demonstration project to be conducted in Southeast Alaska, this study will focus on evaluating performance of WMA binders and mixes in cold weather conditions. How properties of original binder change with the addition of the Sasobit wax, and the correlation between the content of the Sasobit additive and the Superpave Performance Grade (PG) and binder stiffness will be assessed.  The engineering properties of control and WMA mixes will be investigated in the laboratory as well including low temperature performance (by TSRST), rutting potential (by Georgia Loaded-Wheel Tester), dynamic modulus (by Simple Performance Tester) and moisture sensitivity (according to ASTM D 4867).  The research findings will provide recommendations to determine the suitability of WMA technology for Alaskan conditions.

Final Report

Evaluation of Warm Mix Asphalt for Alaska Conditions
16 Jul 2013

Evaluation of Warm Mix Asphalt for Alaska Conditions
Juanyu Liu, Ph.D., P.E.

Related Project Activity

16 July 2013

Evaluation of Warm Mix Asphalt for Alaska Conditions



17 September 2009

Liu and Zhang Brief on WMA in Alaska

by Joel Bailey

Jenny Liu and Lily Zhang presented their project summary on warm mix asphalt applications in Alaska conditions. The slide presentation is available: WMA_projectMeeting_09172009.pdf