ForConstructionPros.com

It wasn't a large project by any means, but the $300,000 repaving of three residential and three connector/business roads in the Town of Indian Trail, NC, represented a significant application to demonstrate the benefits of warm mix asphalt for other North Carolina road agencies and the NCDOT in particular.

Greg Tucker, project manager for Boggs Paving Inc., says the project was completed in early November, and it represented the first major resurfacing project of this bedroom community southeast of Charlotte. Part of the project was a typical mill and fill repaving, and the other involved resurfacing existing pavements.

"After we were awarded the project, we installed an Astec Double Barrel Green system (which uses water to create a hot foam asphalt to coat the aggregate) at our Monroe production facility," Tucker notes. "We then went back (to the Indian Trail's town officials in charge of road construction and maintenance) and presented them with the option to give us a shot at using warm mix on this project. We were scheduled to work on six different roads, and we wanted them to split the contract specifications 50/50, allowing us to use warm mix on half the work and hot mix on the other."

The Town of Indian Trail agreed to pave three town streets with mix produced at 270 degrees F with 25 percent reclaimed asphalt pavement (RAP) and PG 64-22 liquid asphalt cement (AC) binder. The RAP to be used would be fractionated (separated into the various material components), the AC would be foamed to reduce its viscosity in order to coat the aggregate, and Boggs Paving would produce and place the mix.

On the residential streets, Boggs' crews milled two inches of the old asphalt off so that the new surface mat would match the curb line. On the connector/business roads, crews placed a 2-inch hot mix mat over the existing surface.