Campus & Community

Spire lifted atop new residence hall

It took two weeks to prepare for and nine minutes to carry out, but the 24,000-pound copper-sheathed spire was successfully lifted atop Nagel Hall Feb. 12 and bolted into place.

“It was about as smooth a move as you could make,” said Mark Spiegel, University project manager.

As a crowd of nearly 50 University employees and G.H. Phipps construction officials watched nervously, the 50-foot cone of structural steel, plywood and copper was lifted 120 feet to the top of the new $40 million residence hall named for principal donors Trish and Ralph Nagel.

“Uh, oh. It’s starting to swing,” worried structural steel consultant Brian Heitman, as he carefully watched the lift.

But the wind proved slight on what was a day of bright sun and cobalt blue sky and the crane operator made a deft adjustment to correct the sway. Moments later, the 17-foot diameter spire was settling onto the concrete support ring where Phipps ironworkers inside the structure bolted it to heavy steel fasteners embedded in the concrete.

“This is a major milestone,” crowed Phipps project manager Roger Treichler. “It’s the signature piece for the building.

“It’s also out of the way,” he laughed. The spire was built weeks ago in Nagel’s east courtyard but had to sit while workers finished the concrete support for the mammoth spire and made sure the concrete had cured long enough to hold the weight.

Curing typically takes 28 days, but an additive allowed the structure to reach the 5,000-pounds-per-square-inch rating necessary in only five days, said Mike Murphy, Phipps project superintendent. By the time the concrete finishes curing, it’ll be even stronger, he said.

Work to complete the exterior has been delayed by weather, Murphy added, noting that crews were finishing the last section of roof. When completed, the building will be “dried-in,” the point of construction when the exterior is sealed so interior work is not affected by weather.

The interior work includes two mock-up residence units on the first floor.

“The mock-ups are so the design team can check the finishes, paint and quality of construction so the team knows what to expect,” Treichler said.

Also being installed are elevators and the mechanical, plumbing, fire protection and electrical systems. When completed in mid-summer 2008, the 150,000-square-foot hall will provide 364 beds in addition to food court-style dining and offices for the Department of Psychology.

University officials are hopeful the building will qualify for “gold” status under the U.S. Green Building Council’s LEED standards for environmental construction. If the designation is granted, Nagel Hall will be the second DU structure to achieve gold standing. The first was Ricketson Law building in 2003.

“We’re in the range of getting LEED gold,” University Architect Mark Rodgers said recently.

During the lift, though, Greg Hanson of B&C Steel wasn’t thinking about gold. He was focused on being hoisted in a steel basket to the peak of the Nagel spire so he could unhook the crane.

To observers on the ground, the airborne mission appeared harrowing, but to Hanson, it was all in a day’s work.

“The wind was good today,” he said upon returning to earth. “It was a great view.”

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