Warm Mix Asphalt: Experimental Features in Highway Construction

Abstract and project information last updated: 1 March 2011. Project updates are dated below.

Road construction equipment used to mix a special asphalt mixture is pictured, sitting on gravel ground. The equipment is yellow with a green box in the center.

Credit: Jenny Liu

Equipment utilizing double barrel green foaming warm mixture asphalt is used during paving of a field site in Tok, Alaska in June 2009.

AUTC
Project
Number
MISC5
Principal
Investigator
Juanyu (Jenny) Liu (UAF)
jliu6@alaska.edu
Funding
Agency

Alaska Department of Transportation & Public Facilities

Project
Budget
75000
Start
Date
1 September 2009
Estimated
End Date
1 May 2010

Abstract

Hot mix asphalt, used in many conventional paving projects, typically is spread at temperatures between 280° and 320°F. Using warm mix asphalt, which can be applied at significantly lower temperatures (250° to around 270°F) may reduce the energy requirements (and the costs) for paving highways — if it can be used without adversely impacting pavement performance. One form of WMA involves adding small amounts of water to the dryer drum (the asphalt mixer system). ADOT&PF used this approach on a paving project near Tok, Alaska. Researchers performed simple performance tests and indirect tension tests on the new pavement to characterize the mix and to determine if there was any significant difference between the HMA and WMA pavements.