Filling In With GPS

May 1, 2009

Olin Ellsworth may be “twenty-something,” but he still considers himself “old-school” when it comes to construction work.

So when the heavy construction manager for Ronald Franks Construction of Savannah, TN, initially considered how he might successfully land the Reedy Creek Dam project, his first thought was of a conventional, total station approach.

The project will create a watershed lake of almost 1,000 acres in Huntingdon, TN-the largest such lake in the western part of the state. The dam embankment will involve 650,000 yards of fill, extending almost 2,500 feet long and 350 feet wide. It will include a dam bank access road, a blanket drain system, a slurry cutoff wall and a spillway structure and walking bridge. The first phase also involves the clearing of 400 acres. Work began September 15, 2008, with completion time frame of 455 days.

Ellsworth found himself locked in competition with a handful of larger construction companies in the bidding process. He knew he would have to find ways to maximize his efficiency and productivity to successfully win the bid. In discussions with Rob Binder and Tim Marshall-representatives of the Nashville offices of Earl Dudley Associates, based in Atlanta, GA-Ellsworth was asked to consider how Global Positioning System (GPS) technology from Topcon Positioning Systems Inc. could help him secure the bid.

“At first I wasn’t very enthusiastic,” Ellsworth admits. “I finally said, “˜Yeah, I’ll look at it.’ All the while I was telling myself, “˜I’m not going to buy it.’ But I actually wound up buying it before they left that day-and it has proved to be one of the best investments I’ve ever made.”

The original purchase of a HiPer Ga base and rover-along with an FC 120 data collector with Pocket 3D software-quickly paid for itself. Ellsworth subsequently added a 3D machine control system to a Cat D6N dozer. His “ultimate Christmas wish list” is to have every piece of earth-moving equipment at Ronald Franks equipped with Topcon GPS equipment-the 3DMC for dozers, the 3D Xi for excavators and the 3Di for scrapers. “I wish I had it on every machine out there right now. But we’ll get there,” he says. “And, believe me, it will be sooner than later.”

There are two main reasons the equipment and technology work so well, Ellsworth says. “I do 90% of the survey layouts myself, so it’s important to be as efficient as possible. It was easy to see how much time this would save me and how much more efficient it would make me and my crew.

“It cuts layout time at least by half, and I’m able to gather more detailed topography than I ever could have otherwise.” Ellsworth mentions a 20-acre barrow pit that would have formerly taken two hours to cross-section. “With GPS, you can accomplish the same work in 15 minutes,” he says.

And with multiconstellation signals available via the Global Navigation Satellite System (GNSS), downtime is reduced by negating the possibility of poor geometry by having sufficient satellites accessible to produce accurate positioning metrics. “There’s no guessing or having to stop for survey work to determine how much has been done,” he says. “You can plug in the date and time, pull the file and verify exactly how much dirt has been moved…virtually down to the shovel and scoop full.

“Knowing and being able to verify how much dirt you’ve moved is critical. Ten thousand yards of dirt can be a relatively small fraction of the overall project, but it can represent a whole day’s run…and that can mean several thousand dollars.”

Such information is invaluable in controlling job costs and providing the level of documentation necessary for partial pay verification.

Photo: Ronald Franks Construction
Ricky Cooper uses Topcon equipment to make more efficient passes in forming the Reedy Creek Dam embankment.

“Without it, your operator has to spend time out of the dozer checking and setting slope stakes by hand,” Ellsworth says. “With GPS, it allows you to eliminate intermediate staking-which can be a huge cost on large cuts-and you need fewer slope stakes. It also allows you to eliminate hubs. It’s far superior in terms of showing the operator where he is on the job-both vertically and horizontally. It gets you exactly to the correct grade settings the first time and every time-making every pass count. And that saves you the dollars and time that the second pass would cost.”

The technology also helps in terms of crew utilization. “The need for finish operators in the industry today is at a premium,” Ellsworth notes. “There’s no replacement for experienced operators, particularly given the cost of equipment and fuel and the pricing pressure the bidding process imposes. But GPS equipment and technology helps by allowing you to train new operators more quickly, getting them up to speed more quickly. Not to mention when the grader operator is out of the cab doing grade checks, the dozer is idling and I’m losing money.”

With the capabilities offered by Topcon equipment and technology, dozer operators “don’t have to sit idling, waiting for a survey crew. The information is there, immediately at hand. It’s like having a machine operator with a full-time surveyor there in the cab with him at any given time. You’re not waiting, you’re working-all the time.” Consequently, work that formerly took hours and in some cases days can be done virtually instantaneously.

To illustrate the point, Ellsworth observes that the model for the Reedy Creek Dam blanket drain was built in an hour and the information then loaded, allowing the dozer operator to go to work immediately. “Had we been faced with using a total station approach, it would have been more, much more, work than bargained.”

The Topcon system used by Ronald Franks “gave us a significant advantage” in securing the Reedy Creek Dam bid, Ellsworth contends. It also will allow him to complete the project ahead of schedule and at or below budget, he predicts, based on progress made in the project’s initial stages.

And the equipment and technology are just as practical for smaller projects, Ellsworth notes. On smaller projects, utilities, building pads, ditches, and drainage structures have to be accommodated. A conventional wood-in-the-ground approach can actually impose additional obstacles to be worked around, increasing the time and associated expense to complete the project.

Marshall said a concern that GNSS equipment and technology could make surveyors obsolete is unfounded. “They won’t be left out, but their jobs will evolve,” he says. “They’ll have significant contributions to make in the area of site modeling, data services and alignment files that will be needed to load into the equipment. They will still be controlling the job-just not so much via boots on the ground.”

But GPS equipment and technology alone are not enough to help contractors like Ronald Franks succeed, Ellsworth emphasizes. “Rob and Tim and the folks at Earl Dudley are members of my team,” he says. “They understand the equipment and technology. They understand my business. And they understand how to make them work together to create solutions that help me succeed.”