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Even as it nears completion,
the structures lab in the Gunness engineering building looks like a construction
site. Stacks of steel beams. Metal shavings and concrete footings. Lengths
of chain swinging from the ceiling.
That's exactly how civil engineering prof
Scott Civjan wants it to stay. "It's a mess," he sighs, not
unhappily. On the day we visit, two graduate students are testing blocks
of concrete that look rather small until Civjan points out they weigh
a half-ton each. Soon, the sounds of a jackhammer are heard in the lab.
It becomes clear: this is not a construction site. It's a deconstruction
site.
This new lab, and the hiring of Civjan himself
in 1998, reflect an effort by the College of Engineering to rebuild a
program that was allowed to lapse in the mid-'80s. Here, as in many Northeast
engineering schools, the downscale mirrored the slump in the economy.
Structures engineering, after all, has everything to do with growth
with new bridges and buildings, overpasses and roads.
Until recently, therefore, most research
in the field was confined to structural mechanics and analysis - to computer
modeling. Civjan's work represents a rejuvenation of the experimental
side of structures, the hands-on trials that allow computer models to
be tested and refined.
But "hands-on" comes with quite
a price tag. For a large-scale, three-year test, just the materials being
tested can cost $20,000 or more. The total for a big test can be as much
as $300,000. And that's after the lab's initial setup, which is expected
to total $200,000. The burden of this hefty tab was eased by a gift from
Barker Steel, a Milford-based firm owned by civil engineering grad Bob
Brack '60.
"We try to help out," says Brack
modestly, as though his idea of help were not ten tons of steel beams,
bolts, and connectors. Before Brack's donation, the lab was little more
than drawings and a whopping amount of Civjan energy.
A second donation supported
literally the lab's foundation. The installation of a three-ton
capacity bridge-crane, which makes possible the delicate maneuvering of
beams weighing half a ton or more, required a structural analysis of the
existing building. The analysis was provided by alumnus Parviz Heravi
'75G and professor emeritus Fred Dzialo. On their recommendation, four
strengthening columns were installed, and work on the structures lab could
begin in earnest.
The heart of the lab is the load frame,
where the large-structures testing takes place. Into this eighteen-foot-long,
fourteen-foot-high grid of steel and braces, researchers load their favorite
flavor of beam steel, concrete, fiber-reinforced plastic,
wood and apply up to 200,000 pounds of force to one or more
points.
How important are such tests? Imagine a
building's internal structure, steel beam bolted to steel beam. Can you
make the building two stories high? Six stories high? How strong are the
bolts, the reinforced concrete footings? How strong are the load-bearing
beams being used in the new townhouse complex down the road, or the new
off-ramp that leads to the townhouses? On the load frame, says Civjan,
"we push on a column until it breaks." That's more pressure
than it would ever have on it in practice, he says, and it's "what
lets you know how to design against maximum load." The test is the
difference between knowing that a structure will hold and hoping that
your computer model does.
Civjan's next task is to find funding for
the first long-range project. He's reluctant to talk about how many grant
proposals he's already written, as if stating the number is a jinx. "We've
got more ideas for projects than we'll ever be able to do in this lab,"
he says. "The problem is getting funded. Let's just say that if I
get one long-range grant this year, I'll be happy." It's an uphill
battle for him: he's a young faculty member, not yet widely recognized
in his field; he's at a university with a fledgling experimental structures
program and a laboratory not yet completed. "It'll be easier when
we're up and running," he says.
Research isn't the only goal of the structures
lab. As evidenced by those jack-hammering students, it's a teaching lab
as well. A class that's been testing beam sections can now test entire
twenty-foot beams, Civjan says, and "watch instead of being told
what will happen to them." That's important to Civjan as a teacher,
and it's important to Brack, who remembers exactly that aspect of his
education. "UMass gave me so much," he says. "It was very
hands-on. You don't forget that."
The first short-term project using the load
frame is almost ready to be tested. First up will be graduate student
Annapurna Gorthy's computer model of a seismic connection detail. "She's
doing the analysis without the beams," Civjan says. "Then we'll
test five beams, ten beams, compare it to her model and then we can tweak
that model to do hundreds of tests." Many assumptions are made in
computer modeling, and each experimental test, each 200,000 pounds of
force, eliminates some of those assumptions, making for safer bridges
and buildings.
Under that much force, the beams sometimes
"completely deform like spaghetti," says Civjan, hands and fingers
twisting in emulation. And sometimes, the beams fail.
When the beams fail, do they crack?
"Usually." There is the hint
of a grin.
Do you look forward to that sound?
"Yes indeed." He breaks into
a full-fledged smile. "That's my favorite part."
Karen Skolfield '98 G
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