University of Notre Dame
Academic Building's Sandy Soil
Demands Careful Sitework

by Elaine Schmidt

Building solid footings was the first step in reaching for the stars on the University of Notre Dame Jordan Hall of Science.

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The $70 million project in South Bend, Ind., will create a new home for the university's chemistry, biochemistry, biology and physics departments. The 201,782-sq.-ft. building will also hold two 250-seat lecture halls, greenhouse, teaching labs, herbarium, department offices, rooftop observatory and 150-seat multivisualization room. Work began in early 2004 and is slated for completion in May 2006.

A Sandy Site

The project's sandy site presented concerns from the outset.

"This part of Indiana is made up of glacial till and lake sand, so the soil was just too loose for conventional footings," said Doug Schlagel, director of construction and quality assurance for the university.

"Several different scenarios were studied, including overexcavation in both depth and width," added Mike Holtkamp, senior project manager for Geupel DeMars Hagerman LLC of Indianapolis, the general contractor and construction manager on the project. "That would have meant hauling out the old soil and bringing in clean fill, but that would have required additional soil retention systems. It was too expensive."

In the end, GDH and the university decided to use a method of vibratory compaction to create workable soil conditions for the structure.

Also known as "vibrocompaction" or "vibroflotation," vibratory compaction uses vibration to densify deep, granular soils.

Explaining that the densification is done under column pads, Schlagel said, "If you have a column pad that is 9 ft. by 9 ft., you would have six or seven probe locations.

"The technology has been around for 10 or 12 years. It is used in refineries or in facilities built on lake-or waterfronts. It's not often used in the middle of cornfields."

He said the process requires inserting "a probe into the ground to a specific depth. As you retract it, it vibrates and densifies the sand." While the probe is making its way upward, clean fill is dumped at the surface, around the probe.

Schlagel added that the vibratory compaction contractor, Odenton, Md.-based Hayward Baker Inc., guaranteed a load-bearing 10,000- to 12,000-psi postcompaction. Postcompaction tests revealed a bearing capacity that averaged 12,000 psi, hitting peaks of 30,000 psi in some areas.

Has Gothic Style

Done in the academic Gothic style that is a Notre Dame trademark, the building is being constructed of high-end materials applied with old-world craftsmanship.

"We use building materials on this campus that are going to last a long time," Schlagel said. "We use a block back-up on our veneer, structural steel and slate roofs. This building will be here in 100 years."

In addition, the building is full of one-of-a-kind details.

"We are trying to make this building say that it is a science building through visual elements and finishes," Schlagel said, pointing out the depiction of the
Da Vinci Man and a compass with directional arrows in the terrazzo floor.

Holtkamp said it took seasoned journeymen to construct the detailed, five-color brick pattern on the building's exterior and the five-color slate pattern of the roof.

He added that it was not hard to find well-trained, highly skilled workers because the amount of work that Notre Dame has provided over the years has been enough to keep a good number of such craftsmen in the South Bend area.

But using highly specialized workers presented scheduling concerns.

"This is not like building a development or a big-box store," Holtkamp said.

There are not hundreds of people around who can do this work. We have a lot of men and women working on this project and we have to coordinate their time very carefully."

The structure was enclosed and heated as soon as possible to keep both interior and exterior work flowing smoothly.

The project's high-end materials also presented some concerns.

"These are not shelf items," Holtkamp said of items such as the roofing slate and terrazzo flooring. "You have to get submittals in early and get them approved so that you leave time for these items to be fabricated."

Ventilating a Lab

The ventilation requirements of the science labs mandated specific HVAC demands.

"We have dedicated lab exhaust, so the labs are always in a negative condition," Schlagel said. "That way, if there is ever a chemical spill in one of the labs, it will be contained." The negative condition is maintained by high-dilution plume blowers that draw air out of the labs.

Fitting the ductwork for 220 fume hoods into the interstitial space required careful planning.

"We have one person leading our MEP rough-in coordination effort,"
Holtkamp said. "Some companies have one guy who goes to all of their jobs, but we have one guy just on this job."

The building looks to the future not only through the use of materials that will be around for a century but also in terms of flexibility.

"The labs are laid out in a modular form in both a horizontal and vertical fashion," Schlagel said. "They are very repetitive in both directions so that we can reconfigure or convert the space in the future should we want to."

Flexibility has also been required in dealing with the rooftop observatory. The telescope, which will be wired to the multivisualization room to allow a room full of viewers to see the images on which the telescope is focused, has not yet been purchased. The observatory will likely be completed before the still-to-be-purchased telescope is on hand.

Schlagel pointed out that telescopes, like most technology, have shrunk in size and increased in power in recent years.

"Telescopes are not as big as they used to be," he said. "Still, we are hoping that we aren't going to have to rent a crane in the future to put this thing up on the roof."