The RCC Pavement Council has a new publication titled “RCC is the Right Choice for Busy Interstate Exchange” and touts that the structural strength of Roller Compacted Concrete (RCC) pavement stands up to heavy truck traffic, with thinner pavement, longer life, less maintenance, and less downtime. A very busy interchange at Exit 104 on Interstate 59/20 (I-59/20) in Jefferson County, near Burmingham, Alabama, USA, not only has an active truck stop at the exit, but the road carries traffic from a large rail to truck intermodal facility and a large distribution warehouse.
Ken Couch, P.E., County Transportation Engineer-Birmingham area Alabama Department of Transportation (ALDOT) said, “This is a typical diamond interchange, but the high truck counts have contributed to the asphalt deterioration on both sides of the concrete bridge. The City of Bessemer, Jefferson Country, ALDOT, and the Federal Highway Administration (FHWA) have worked together to fund the project—with the goal to restore the pavement so it can withstand the heavy truck traffic.”
If the original plan to design as a building up of the asphalt road to provide the pavement strength needed, then the bridge crossing the interstate would have needed to be raised—a very costly solution. To remain on grade with the bridge, the final decision was to remove the asphalt, dig deeper, and place the extra material. ALDOT explored RCC Paving as the solution to minimize the amount of digging. Although RCC is commonly used in industrial areas, this was the first RCC pavement project for the Birmingham area.
Terry W. Robinson, Acting Bureau Chief-Innovative Programs Bureau-ALDOT said, “Although the concrete is not as deep as traditional asphalt, RCC provides the structural strength needed in areas of heavy truck traffic.”
Because RCC does not rut or ‘shove’ as large trucks stop, start, and turn, the length of the pavement life and lower maintenance costs added to the benefits of RCC for the interstate intersection.
“We had to keep traffic flowing and RCC could be placed quicker than conventional concrete at the depth that was being used.” The initial cost was a little higher, but [the life of the RCC pavement will be] 20 years versus 10 for asphalt,” explained Couch.
To allow time to cure and to minimize traffic at the work site, lanes across the bridge and entrance/exit ramps were constructed in phases while traffic was re-routed to the next interstate exit. Chris Carwie, Business Development Manager-A.G. Peltz (contractor) stated, “This pavement must meet rideability specifications set by ALDOT and the pavement design is thinner than what is typically required for an intermodal facility’s container stacking operations—a single-lift RCC was possible—10 inches were placed in one pass.”
He added, “An unanticipated detail work at the top of the entrance and exit ramps required cast-in-place concrete for the transition from the RCC pavement to the ramp. It was an efficient process with the same paver used to spread and compact the base that was used to place the RCC.” He sees RCC as a potential solution for road projects that have long, uninterrupted stretches of pavement for which temporary lane closures are needed to allow cure time and will recommend RCC to his supervisors in the future.
For more detail, and the entire PDF publication titled “RCC is the Right Choice for Busy Interstate Exchange”, please go to: http://rccpavementcouncil.org/wp-content/uploads/2018/09/RCC-is-the-Right-Choice.pdf