Lowering the Stakes...For Good

Dec. 17, 2014

Managers may want to consider the potential time savings of stakeless and stringless curb work.

Contractor A. Folino Construction of Oakmont, Pa., was recently tasked with constructing a parking lot for the $100 million, 74,000-sq. ft. Wexford Medical Mall.

The job included 9,000 feet of slipformed curb and curb islands. “We had all the exterior site concrete work, which included curbs, sidewalks, miscellaneous deck slabs, and loading dock walls,” says Mike McFarland, Folino’s general superintendent.

Folino previously used subcontractors for curb portions of its paving jobs, but found that curb placement had too much of an effect on its paving schedule. “We felt it was something we should move in-house to have better control over,” McFarland says.

To do the work, Folino acquired a Wirtgen SP 15 slipform paver equipped with the AutoPilot system, a GPS-based stringless paving system. “We felt that since we can increase production by not having to have the steps of installing and removing stringline on a job, with stakes in harm’s way of our [parking lot] grading operation” McFarland says.

The proprietary system bypasses the need to establish a digital terrain model, as programming is completed using a “Field Rover” pole to capture coordinates, or by using job site plans—meaning a surveyor isn’t required.

For course control, two machine-mounted GPS receivers communicate with an additional GPS reference station positioned on site. For precise grade control, a laser, ultrasonic sensor, or total station is used. The machine control software is also proprietary.