ACE of Hearts

Cardiac center challenges construction team

St. Luke's Medical Center Cardiac Center and Patient Tower

Photo by Hedrich Blessing, Steve Hall 2004

It's tough to build a building on top of a building, which is why people usually work from the ground up.

But that wasn't an option for the team that put together the St. Luke's Cardiac Center and Patient Tower. Aurora Health Care wanted its new eight-story ward built on top of its parking structure.

"The building below is still separate and functional from the building above," said James Hayes, director of health-care services and principal of project engineer Graef, Anhalt, Schloemer & Associates.

The crew had to drive 33 structural columns around and through the existing parking structure and into the ground, where they were bolted to the bedrock. The team had to create wide distances between the columns and use fewer than was convenient because the parking structure could only handle so many holes before falling apart.

Each column supports a 7 million-pound load.

"[The parking structure] is very sensitive to openings, and here we were making Swiss cheese out of it," Hayes said. "To do this, we had to limit the number of columns because too many columns in the building structure would not function too well in the parking garage."

The I-beams that were placed above the columns also posed challenges. Some weighed more than a ton a foot, and they were too heavy to assemble on the ground and lift into place, said Nick Stromer, vice president of construction management for The Boldt Company. So crews, suspended above the parking structure, had to rivet the trusses toge-ther in place.

	Project Name: St. Luke's Medical Center Cardiac Center and Patient Tower Location: Milwaukee Submitting Companies: Graef, Anhalt, Schloemer & Associates Inc., Milwaukee; The Boldt Company, Appleton; Kahler Slater Architects, Milwaukee Construction Manager: The Boldt Company Architect: Kahler Slater Architects Engineers: Graef, Anhalt, Schloemer & Associates Inc., structural and civil engineer, and Ring & DuChateau Inc., Milwaukee, plumbing, HVAC and electrical engineer Owner: Aurora Health Care, Milwaukee Project Cost: $182 million Start Date: July 2000 Completion Date: March 2004

"Some of them had thousands of bolts in them, and the connection plates for some of the trusses were 8 feet tall," he said. "It was huge. It really was."

Aurora was keeping the project on a tight schedule, so Kahler Slater Architects had to design the expansion before anybody knew if the bedrock could handle the weight on each column. Luckily, the earth beneath St. Luke's was strong enough to handle the load. Without that, the project could've cost a lot more, and Kahler Slater would've had to make copious revisions.

Nonetheless, this project was subject to a lot of midproject design revisions due to advancing medical technology, said Dan Morgan, Kahler Slater's project manager.

The design team had to rework the floor plan after the medical center switched to a larger and more powerful sterilizer for the building.

"Whatever you might design at the front end might not be available by the time the project is completed," Morgan said "We have to be ready to make those changes on very quick notice. That changes on every project we do."

Timing was crucial for the project since St. Luke's was eager to open its new cardiac center before the competition opened new hospital branches.

"They wanted to have their benchmark facility up and running," Morgan said. "They needed this project to keep that edge on the marketplace, and they've got it."