Masonry Variations – From Start to Finish
Sometimes the word “classic” can be misinterpreted
as “old fashioned.” To prevent building designers
from making that mistake, BAC and IMI created a national
exhibition to rekindle designers’ interest in masonry
construction, and to keep classic masonry materials on
an equal footing with new ones. That was the genesis of “Masonry
Variations” at the National Building Museum in Washington
D.C. launched in October 2003.
 |
| IMI Southwest Regional
Training Director Keith Behrens (BAC Local 1 TX/LA)
performed a low-tech, but effective, test on the brick
leg mockups. “We knew we were headed in the right
direction when we were unable to break them,” he
says. |
Guest curator Stanley Tigerman, FAIA, began the process
by tapping four recognized architects, then challenging
them to push the envelope of masonry design by focusing
on one of these four materials: marble, brick, terrazzo
and AAC.
While each material held a specific design challenge,
brick proved even more demanding because of its long history,
precedent, and commonality. Facing this challenge, Carlos
Jimenez, of Carlos Jimenez Studio in Houston, posed the
question, “Does a brick really want to be an arch?” He
determined the answer was no.
His mission now began in earnest: to free brick and allow
it to float. To assess the possibilities, he turned to
his collaborator, IMI Southwest Regional Training Director
Keith Behrens, a member of BAC Local 1 TX/LA. Their first
step was to “open” the brick unit up, and look
inside for the answer. That led them to use the “shells” of
brick to fashion three squares, each made of reinforced
and grouted brick “legs.” With the aid of the
reinforcing metal framework, each square was able to pivot
360 degrees. Each masonry square was held within each other,
and able to move freely.
 |
| The exhibit generated
plenty of attention from the public and media, and
lots of questions about how it was accomplished. The
answer? Teamwork between skilled BAC craftworkers and
talented designers. |
For three months they tested the concept, learning several
valuable lessons. First, it seemed silly to break bricks
apart, only to grout them back together. Second, the grouted
reinforcement system was sturdy enough to allow for rotation,
but took away from the delicate concept of brick being
free. So it was back to the lab – or in this case,
the IMI training center in Houston.
There, Behrens discovered that if the legs were made lighter
and post-tensioned without grout, the assembly would move
more smoothly and help reduce deflection across the overall
lengths. He also found easier ways to lay a brick pier,
with the metal rods as guides, and kept the cores clean
for more efficient post-tensioning. “We saw the holes
in the brick as opportunities,” says Behrens.
Structural engineer John Swink, P.E., of ACME Brick Co.
made a key contribution by designing an “outboard” pivot
that allowed the weight to bear down, not out. Post-tensioning
from the end brought greater strength and a more appealing
look.
With a tight on-site construction schedule, all the installations
were started off-site and assembled to varying degrees
in the Museum galleries.
 |
| A reinforcing metal
framework allowed each brick square to pivot 360 degrees.
Post tensioning without grout made the legs lighter
and more mobile. |
Curious to know if masonry materials could capture light,
Jimenez visited the idea of the “core.” He
selected five brick profiles, which Behrens arranged into
a constellation, allowing light to flood out of the floor
while the brick squares moved.
All told, the brick installation took roughly six months
to conceive, test, and rework, followed by three weeks
of off-site construction and four on-site. The one element
most responsible for their progress was the collaborative
spirit that both craftworker and architect brought to the
project. As IMI project coordinator Maria Viteri, AIA,
notes, “When you want to make brick spin, it takes
more than a concept. It takes patience, trial and error,
and most of all, trust.”
|
