Two Link-Belt 90-ton (81.6 t) assist cranes were used, one on each side of the interstate, to help guide the ends of the bridge into place for bolting.
Imagine the difficulty of lowering a 270 ft. (82.3 m) long steel footbridge in place over a six lane interstate highway — during the night.
Such was the task facing Rockingham, N.C., based Superior Cranes Inc.
The company accomplished it by utilizing its 800-ton (725 t) DeMag all-terrain crane to handle placement of the four section bridge, which it had transported in pieces from Rockingham, and welded together a few days before on the shoulder of I-40 near Durham, N.C.
The $9 million project had been in the works for years, delayed by engineering problems and budgetary difficulties.
The footbridge forms part of the American Tobacco Trail. The trail rehabilitates an abandoned rail line originally built for the American Tobacco Company and now used for cycling, walking, and jogging. In addition, the local stretch of the trail links to the East Coast Greenway, a multi-state project that will in due course connect Maine to the Florida Keys.
Working under floodlights on April 28 from midnight onwards, the bridge was lifted into position and bolted on four piers, two on each side of I-40.
“Our 800-ton hydraulic crane was the crane selected to set the bridge. This crane is the largest hydraulic crane in North Carolina and the only one that would do the job, and it also performed a similar move at the Charlotte Douglas Airport a week later,” said Joe Everett, president of Superior Cranes Inc.
“Regarding assembly, the only way you could perform the lift was to set the bridge in one piece/one lift, because you could only close I-40 for one seven hour window. By assembling the bridge on the side of I-40, and setting it on gantries, we were able pick the bridge and set in one lift. We came in under time and had the interstate closed for approximately six and a half hours,” said Everett.
A second crane was used to set counterweights for the 800-ton (725 t) crane, Everett said.
“This was a quicker, more efficient way to get the counterweights loaded so that we could proceed with the lift. All of the counterweights were lined up on trucks to expedite assembly and disassembly. A 110-ton Grove crane was used to unload the counterweights from each truck and load onto the 800-ton. The smaller crane operates faster than the larger cranes.” Two Link-Belt 90-ton (81.6 t) assist cranes were used, one on each side of the interstate, to help guide the ends of the bridge into place for bolting.
“While the actual setting of the bridge only took 15 minutes, the preparation before and the fine-tuning and disassembly afterwards is what was so labor intense. From Superior Cranes Inc.’s aspect, it took almost a year of planning to make sure that the lift/set ran smoothly,” Everett said.
Founded in 1989 by Joseph C. Everett, Superior Cranes Inc. has one of the largest work forces in its line in the Carolinas, according to the company. Handling hydraulic gantry systems and specialized jacking as well as offering 24-hour emergency assistance and other services, Superior Crane’s equipment fleet includes cranes with capacities up to 800 tons. Its cranes include rough terrain, hydraulic, truck and crawler models, and its fleet also includes tractors and trailers up to 500 tons (453.6 t).
Based in Rockingham, N.C., the company has branches in Charlotte, New Bern, Raleigh, Greensboro, Wilmington, and Winston-Salem in the state as well as in Columbia and Florence, S.C.