C+S July 2020 Vol. 6 Issue 7 (web)

opened in April 2019, marking the completion of Phase 2 of the $50 million initiative. The final stage of the project is scheduled to finish in the fall of 2019. Initial construction began in November 2015 and CES crews were on site from day one. Every day for three years, field teams were using their survey equipment for installing control points, and staking out curbs, piers, girders, columns, as-builts, and bridge bents, which are structural elements used to support girders. They also used their tech- nology to locate existing storm and sewer infrastructure and stake out new construction points for rerouting and replacing those systems. “We had extremely tight tolerances to ensure all the pre-fabricated steel beams fit correctly and were at the correct height and horizontal plane dictated by the design,” says Hudson. “All of our measurements had to be exact.” In the latter stage of Phase 2, CES was asked to perform as-built surveys of the support columns for the elevated roadways and bridge ramps. As they had just acquired an SX10, the timing proved opportune. CES had been doing column as-builts with their traditional equipment and it was painstaking. To capture the circular columns, crews needed to measure the circumference, shoot multiple points around the col- umn, bring that data back to the office, and then calculate the “best fit circle” to indicate the column center. Using the scanning function of the SX10 allowed them to capture the entire column at once. “In addition to the time-consuming process, traditional techniques require a prism, which can introduce some error because of its thick- ness,” says Hudson. “So you have to perform many calculations and checks to ensure you’re precise. With scanning, you get the actual surface so it’s easy to pinpoint the column center.” With the SX10 available, a field team opted to scan seven remaining bridge columns––the instrument’s debut project at CLT. After re-establishing site control––given the confined, active work site, they had to verify control every day––the two-person crew set the

“That’s not easy to consistently maintain when you have such a cha- otic, machine-heavy and sometimes cramped work site. But despite the challenging and unexpected conditions, we’ve been able to stay on spec every day.” And since the summer of 2018, they have been able to extend the breadth and detail of their data through the addition of Trimble’s SX10, a scanning total station that combines surveying, imaging and scan- ning. That functionality has proved particularly useful for two other massive airport projects: the Elevated Roadway (EVR) and the South- Crossfield Taxiway (SCT). “The SX10 has become instrumental on CLT projects,” says Hudson. “It’s not only giving us the flexibility, speed, mobility, precision, and safety we need, it’s reinventing some of our historically tradition- al survey approaches and creating new business opportunities.” Elevating efficiency An extensive, four-year undertaking, CLT’s EVR project is widening the existing four-lane terminal approach road to 16 lanes to create more badly needed space for vehicle drop offs and pickups. Five new up- per lanes of the EVR and four temporary passenger walkways were

The new and improved Concourse A at Charlotte Douglas International Airport (CLT), the first completed project under the Destination CLT initiative.

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