Driven deep into the ground, steel pilings are first stage of UND med school project
“Piled higher and deeper” is an old college joke about a Ph.D. degree, but the prep work going on to lay a foundation for UND’s new ivory tower makes the terms ring loud and literal.
Two big cranes are pile-driving steel pipes 165 feet deep through Red River Valley clay down to the hardpan of ancient glacial till to support what will be a four-floors-with-a-penthouse School of Medicine and Health Sciences along Gateway Drive.
The pile-driving is the first stage of the $124 million, two-year construction program that will elevate health education for the state and the university, leaders say.
“This is the largest publicly funded building project in the history of the state of North Dakota,” said Randy Eken, associate dean for administration and finance for the med school.
Pam Sharp, director of the North Dakota Office of Management and Budget, confirmed there hasn’t been this expensive a public building in the state.
University leaders have said it will be a one-of-its-kind, state-of-the-art health education facility.
It’s starting out the old-fashioned way.
All day long, two Swingen Construction cranes drop steel “hammers” — one weighing 6,600 pounds — that become pistons in a simple two-stroke diesel engine. The “hammer’s” 10-foot free-fall creates enough pressure and heat inside the rough cylinder to explode fuel injected each time, driving the steel piles down while bouncing the piston back up for another blow nearly every second.
Heard across campus
The relentless clang of steel on steel isn’t a problem, said Manna Khan, as she parked her car at Hamline Square Apartments on the south side of the site on Friday.
“We hear it a little,” she said of the noise inside her UND housing unit. “And it doesn’t go on at night. They stop about 4 o’clock.”
She and her husband and daughter all attend UND.
“I think it has to be done,” Khan said, gesturing to the construction site. “There is benefit for everyone. My daughter is in pre-med, so we’re very glad there is going to be a new med school.”
Karen Benefield is the deli manager at the University Station convenience store and gas station on the west border of the site, less than 100 feet from the forest of steel waiting to be driven down.
“If I go in the bathroom I can hear it,” she said of the store’s nearest side to the construction. At times she can feel the vibration in the ground from the pile drivers.
But otherwise, with music playing in the store, the diesel hammers can’t really be heard inside the store.
Benefield sees benefits with the project and its workers nearby. “They come in for breakfast and lunch.”
Mike Headrick with PCL Construction Services of the Twin Cities said company representatives visited all the neighboring homes and businesses to make sure there were no problems and haven’t heard complaints.
Blow by blow
The piles, or poles, actually are oil-field steel casing pipe, the size used in drilling Bakken wells, 9 5/8 inches in diameter, said Jason Odegard, vice president of estimating for Swingen.
A 40-foot length of pipe is pounded down until about five feet are left above ground.
While the pile-driving crane moves to the next pipe, a crew lines up another pipe length using a different Swingen crane to dangle the pipe while a worker welds it to the driven pile, to wait for the pile-driving crane’s return for another 40 feet of pounding.
The idea is to keep both pile-drivers going as steadily as possible.
Swingen has a crane with a “small” hammer for starting out each pile and one with a big one to finish the job which gets tougher the deeper the driving.
Starting out, the diesel hammer can drive a pile an inch or more per blow. By the time it’s down into the glacial till of boulders and gravel that becomes a hardpan 130 to 160 feet down, it can take 50 or 80 blows from the big hammer to drive a pile a foot.
A pile is considered driven when the hammer encounters “what we call ‘refusal,’” Hendrickson said. “When we give it 30 or 40 blows and it doesn’t move, we know we are down there.”
Once a pile is seated, it’s filled with concrete.
The same method was used for the Ralph Engelstad Arena nearby, although the piles didn’t have to go as deep.
The result this time will be 11 miles of steel-encased concrete in 350 piles, their bottoms buttressed on hardpan 55 yards down, their tops level with the ground to provide a firm footing for the 78,000-square-foot footprint of the new med school building.
“We started driving piles in the second week in March,” said Headrick, district manager for PCL Construction Services of the Twin Cities, which is running the med school construction project in a joint venture with Community Contractors of Grand Forks.
The extra-cold winter has not been a problem, even though the frost has been as deep as seven feet at the site, Headrick said.
The blizzard March 31 only cost them a day.
“We were going by 10 the next morning, in the snow,” Headrick said. “We are a little ahead of schedule. I think we will be done with piles in early May, actually within days of where we expected to be.”
The 8.3-acre site in the corner of U.S. Highway 2 and Columbia Road has 320,000 “gross” square feet, for parking and other things as well as the footprint of the four-story med school building itself.
The project has been split into 32 construction divisions along lines of work including electrical, plumbing and excavation, with up to 50 or more separate packages for firms to bid on, Headrick said.
Swingen is one of what will be dozens of local and regional subcontractors working on the project over the next two years.
Headrick said 200 or more firms have expressed interest in some part of the project, which will require 200 or more workers during the two years of construction.
Derrick Deering started Monday as an engineer with PCL on the pile-driving.
“I graduated from UND in engineering in December,” said Deering, leaving the trailers that provide on-site offices to go back to monitoring the pile-driving.
“I met him at a job fair at UND,” said Brad Hendrickson, senior project manager for PCL. “We’re lucky we got him.”
Bids worth about $5.5. million already have been awarded, including for the initial dirt moving and the pile-driving, Eken said.
Bid invitations for the remainder of the work went public April 8, with a closing date of April 24 published in the notice.
But Eken said this week it was decided an addendum to some bid packages was needed, which will delay bid closing until about May 1.
Reviewing so many bids will take a while, so the news of who gets what work likely will come around about June, Headrick said.
That means groundbreaking still is on for July sometime, Eken said, with completion still slated for July 2016.