The trucks hauled asphalt 36 miles from the plant in Savannah to the site in Hinesville, Royal says, and there was “excellent project management to coordinate between the roadway and the plant.”

James D. (Darrell) Cannon was the project manager; Joe Hires was the quality control manager. Jeff Andrews served as operations manager and Elmer Baggett, equipment manager, “was a tremendous help in making sure that all of the paving equipment and corresponding electronics were set up properly and in good working order,” Royal says.

Dust breaks the concrete-asphalt bond

Excellent smoothness results on a concrete overlay produced an award-winning project for Duit Construction Co., Edmond, Oklahoma. Duit won a 2008 Gold Award for Excellence in Concrete Pavement from the American

Concrete Pavement Association in the Overlays category.

On a 10-mile stretch of Interstate 35 near Stillwater, Okla., Duit averaged 1 inch per mile of deviation from a 0.20-inch blanking band. The specification called for a maximum of 6 inches per mile. The contractor earned 100 percent incentive payments for 3 inches of deviation or less per section of pavement.

The original pavement consisted of 10 inches of asphalt. A Duit subcontractor milled 4.5 to 5 inches of the asphalt, taking care to control the profile of the remaining asphalt. A properly graded asphalt base helped to achieve the concrete smoothness results. It required four passes to mill the 26-foot wide pavement.

Duit used two concrete pavers to place the 8.5-inch thick concrete overlay. The lead paver, a CMI-made SF 450, a four-track paver, worked 26 feet wide to spread the concrete, which trucks had placed on the asphalt. Mounted behind the lead paver was a dowel bar inserter, which placed dowels at 15-foot intervals. The second paver, a CMI-made SF 6004, performed the finish paving, said Gary Gaul, executive superintendent for Duit. (CMI has been incorporated into Terex Corp.)

It was an unbonded overlay. The dust from the milling operation served as a bond breaker between the asphalt and the concrete.