Articles and Case Studies



PRECAST WITH PRECISION

PRECAST WITH PRECISION

330-ton crane sets precast concrete panels for new Georgia wastewater treatment facility

 

The heart of a new wastewater treatment facility in Newton County, Georgia, consists of a liquid-holding structure made of precast concrete panels. The massive 1.25-million-gallons-per-day A. Scott Emmons Water Reclamation Facility, once completed, will serve growing business activity in the city of Social Circle as well as nearby residences.

The Newton County Water & Sewerage Authority (NCWSA) hired Reeves Young as general contractor. Dutchland, Inc., a specialist in the engineering, manufacturing, and construction of precast concrete tanks and custom-designed wastewater treatment plants, provided precast panels to form the rectangular tank where water treatment will occur. ALL Crane Rental of Georgia, a member of the ALL Family of Companies, was chosen to provide both the crane and its operator to set the precast to build the tank.

For the work, ALL Crane sales representative Jesse Irwin specified a 330-USt Liebherr LTM 1300-6.2, configured with 96 feet of boom set at 48.2 degrees and a 60-foot lift radius. The crane was outfitted with 123,500 pounds of counterweights.

The LTM 1300 was positioned inside the footprint of the tank and constructed the majority of the tank walls around itself, then backed out when only a few panels remained to complete the final wall. After the crane was repositioned outside the tank walls, it set panels for the top of the tank.

Building the tank required 188 precast panels, with construction scheduled to take place over portions of five days. Each precast panel was numbered and scheduled for delivery in meticulous order so the crane picks would occur smoothly.

“At 7:30 in the morning, trucks start arriving with precast panels,” said Randy Schantz, construction supervisor for Dutchland, Inc. “and they keep coming every 20 minutes with the panels for that day’s work.”

Panels can be roughly divided into two categories: walkways, which form the tank’s floor, and walls. However, within those categories, panels can differ in size. The largest panel topped out at 46,000 pounds. “It’s because almost every panel is unique that the trucks must come in a specific order to maintain project flow,” said Schantz.

This level of organization also minimized the number of moves the crane needed to make. “On some precast jobs, the crane might have to pick a panel and then turn it for final positioning,” said ALL Crane’s Irwin. “Here, each panel was rigged from two points at the top, meaning a single crane could pick, lift, swing, and set without having to rotate the panel.”

“There’s a rhythm when you’re doing this kind of work,” said Schantz, stressing the importance of having a good working relationship with the crane operator assigned to one of his projects. “When everyone is on the same page, it’s possible to move through panels relatively quickly while maintaining the highest degree of safety.”

The new water treatment tank measures 206 feet long, 85 feet wide, and 20 feet tall.