Pavement maintenance
Heartland Asphalt crews performed windrow paving to place mix with Invigorate rejuvenator on Cerro County Road S62. Photos courtesy of Colorbiotics, Ames, Iowa
Heartland Asphalt Pushes the RAP Envelope with Invigorate T
The asphalt industry, and asphalt producers in particular, are continually searching for ways to increase recycled asphalt pavement (RAP) content in mix designs. “It makes sense to recycle as much asphalt as we can,” said George Jessen, president and general manager for Heartland Asphalt Inc., Mason City, Iowa. “It will extend the life of our natural resources, and
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it will help our customers by stretching their dollars farther.” The catch, according to Jessen, is to increase RAP use in a responsible way. When increasing the amount of recycled asphalt in mix designs, producers can end up introducing oxidized binder that is harder and stiffer and that affects the performance characteristics of the asphalt. “It can make the asphalt more brittle in cold
temperature times of the year,” Jessen added. This can lead to premature road failure in the field. To prevent adverse road performance, state departments of transportation (DOTs) place limits on the percentage of RAP used in asphalt mixes for state and Federal projects. For asphalt producers in Iowa, this comes in the form of capping binder replacement.
