The Wisconsin Department of Transportation (WisDOT) joined TPF-5(213) as a state partner in 2009. Wisconsin began researching the use of recycled asphalt shingles (RAS) in 2008. In January of 2009 they released a special provision allowing for the use of post-manufactured or post-consumer RAS. WisDOT is one of leading states in the use of post-consumer asphalt shingles and have diverted over 200,000 tons of RAS from the landfills since 2008.
Final revisions to the RAS specification are available in the 2011 Standard Specification. The specification states that when RAS is used alone in a mix it can replace up to 20 percent of the binder in the upper layer and 25 percent in lower layers. When RAS is used in combination with recycled asphalt pavement (RAP) or fractionated recycled asphalt pavement (FRAP) it is limited to 5.0 percent of the total weight of the aggregate blend. The RAS grind size is not separately defined from the recycled material and is included in the aggregate gradation.
WisDOT is currently reviewing their goals and key outcomes for their demonstration project to be scheduled for the 2011 construction season.
Wisconsin DOT Partner:
Judith Ryan, P.E.
Bureau of Technical Services