Summers-Taylor Inc. holds license number 00000069 in its home state of Tennessee, which means it’s the 69th contractor of any kind to be licensed in the state. Founded in 1932 as a general maintenance and construction company, Summers-Taylor is now the largest, heavy and highway construction contractor serving the tri-state region of Northeast Tennessee, Southwest Virginia, and Western North Carolina. Located in Elizabethton, Tenn., the company owns more than 400 pieces of construction equipment and trucks, five concrete plants, and four asphalt plants.

Travel an interstate or major highway in this region, and it has likely been built or repaired at some point by Summers-Taylor. The family-owned company has grown from its modest start and now employs more than 375. The contractor has diversified, adding design and engineering capabilities to its core construction and paving services. Yet, road building remains at its heart.

Not surprisingly, the company is involved with the $18 million Tennessee DOT improvement and expansion of state Highway 75. Just north of Johnson City, the highway spanning between Washington and Sullivan counties is being widened from two to four lanes. The Tennessee Highway 75 project is a 4-mile stretch requiring placement at various locations of concrete curbing and gutters, for drainage and catch basins.

“With its long, straight highway run, this is the perfect project for us to try our newly acquired 3D GPS machine control on our Gomaco GT-3600 slipform concrete curb and gutter paver,” says Lee Thomson, concrete superintendent for Summers-Taylor. “We’re among the first contractors in America running a stringless GPS-based curbing machine—they’re more commonly found in use outside of the States.”

Thompson feels comfortable pioneering machine-control technology on the curb machine because he’s followed the evolution of the technology over the past 10 years, learned how it’s benefiting Canadian contractors, and his company is successfully using GPS technology on the earthmoving and site-grading side of its business.

Slip-form production flow

The Summers-Taylor Gomaco concrete curb machine is equipped with a Topcon GPS+ receiver and an onboard graphical display. A pair of masts, each topped with a Topcon PZS-I laser sensor, are mounted on the machine to control grade elevation and steering. Because Summers-Taylor uses Topcon Millimeter GPS, which uses laser-enhanced GNSS technology, a pair of Topcon PZL-1 transmitters are positioned at control points on the site. Thompson places the transmitters 500 feet apart to track the position of each receiver on the curb machine and relay curb location and elevation data to the Gomaco curb and gutter machine. As the machine progresses, Thompson leap-frogs the transmitters to maintain the slip-form production flow.

The transmitter uses a fan beam signal that Topcon calls Lazer Zone technology. It is designed to emit a fanned signal with a height of 33 feet. Summers-Taylor relied on Construction Engineering Solutions, LLC, Leopold, Ind., to help create the 3D model that was converted via Topcon Office 3D software to the files the curb machine used.