Manatts Inc., an Iowa-based contractor, earns 70 to 95 percent of the available smoothness incentives on concrete paving projects, thanks in large part to the company’s new PaveSmart 3D machine control system from Leica Geosystems.
Late last year, Manatts worked on a $9 million project repaving a nine-mile stretch of U.S. Highway 71 in northwest Iowa. The family-owned business placed a six-inch concrete overlay atop the milled-asphalt pavement while their new GOMACO GHP-2800 slipform paver, fitted with 3D control from Leica, widened the four-lane, divided roadway from 24 feet to 34 feet. They earned the maximum smoothness incentive on about 95 percent of the pavement placed.
“In the old days, when we were paving on string line, if you got 50 percent of the available smoothness incentive payments on a project, that was good,” says Mike Viehdorfer, the project manager for the contractor. “Now that we are running stringless, we expect more and we are getting more.”
Manatts is running the Profile Index (PI) system for measuring smoothness, which is comparable to, but different from, the International Roughness Index (IRI). The Iowa Department of Transportation says it takes a PI of less than 22 inches of deviation per mile from a zero-blanking band to earn the maximum smoothness incentive. On Highway 71, Manatts has been consistently running between 13 and 19 inches of deviation.
Viehdorfer likes PaveSmart 3D for several reasons:
- Leica’s 3D machine control saves Manatts considerable time and money on labor and transportation costs associated with the staking of hubs, setting of blue tops and the setting up, maintaining and tearing down of string lines.
- Automated 3D control also eliminates the potential for human error with string line, and eliminates logistical restrictions around the paver.
- 3D control from Leica Geosystems is more accurate than a string line and integrates seamlessly with any GOMACO paver or trimmer.
- Leica PaveSmart 3D regulates the steering, grade, draft and cross fall of the paver with no need to retrofit complex hydraulics.
- PaveSmart 3D guides the paver in relation to a digitized 3D model of the highway, running on the paver’s Leica Geosystems onboard machine computer.
Tim Tometich, machine-control manager for Manatts, says his company benefits from the GOMACO–Leica Geosystems combination, which is based on a 13-year collaboration. “The value that we have is that GOMACO has built their computer to talk to the Leica PaveSmart 3D computer. The GOMACO computer was built with Leica Geosystems stringless technology in mind, and the two computers talk really well to each other.”
Visit Leica at the 2013 World of Concrete at Booth C-5748