Better Roads Digital Magazine
Issue link: https://read.dmtmag.com/i/85902
Applications&Innovations Iowa Overlay Concrete on asphalt upgrades farm-to-market road by Tina Grady Barbaccia O ak Crest Hill Road South East in Johnson County, Iowa, appears to be just a typical farm-to-market secondary road. But being one of 11 Iowa highway "Stimulus" projects, worth in total $13.7 million, makes it a little less ordinary. So does its new surface. The unbonded concrete pavement overlay of Oak Crest Hill Road from south of the city limits of Hills to the Washington County line was a nearly $1.845-million job completed by Iowa City-based contractor Metro Pavers and funded through the American Reinvestment and Recovery Act (ARRA), more commonly known as "the Stimulus." Iowa received nearly $358 million for state and local roadway, bridge, trail and freight rail projects through the Stimulus, and Governor Chet Culver's I-JOBS initiative kicked in $115 million for transportation projects. The Oak Crest Hill Road concrete overlay covered two lanes and spanned approximately 5.5 miles from start to finish. The county required traffic to be maintained in one direction at all times, says Nick Kempf, co-owner of Metro Pavers. "Because it is not a primary highway, it was not that heavily used, but [the county] still wanted to improve the road system," says Kempf. "They tried to 're-profile' it and 35a January 2012 Better Roads take out some of the bumps." And work went all the more easily, he says, because "most people along the roadway were happy to see the road improved." Straightforward Doesn't Mean Easy The overall job was fairly straightforward, says Kempf, but that doesn't mean it didn't have some challenges. The University of Iowa is located in Johnson County and this means a fair amount of bicyclists. As part of the project, the county asked that bicycle lanes be developed "to make it safer," Kempf says. However, this means the road has an extraordinary width for a secondary road. "The driving lanes are 24 feet plus the extra lane to bring it up to about 34 to 36 feet," Kempf says. As a secondary road, there were no contraction baskets, Kempf pointed out, so his team cut ev- ery 15 feet for joining. There has been a great deal of whitetopping in Johnson County. Concrete overlays have become commonplace in Iowa as an economical means to rehabilitate the second- ary road system. But for this project, rather than beginning with the removal of existing concrete, the concrete overlay was placed over an asphalt roadway. It was also poured on the shoulders that were compacted and then built up to ac- commodate the new bike lines. "We tried to maintain about