kept refining the design for this structure until we made it
work. We worked with the pre-caster and the Department of
Transportation early during the design process to make sure
we could transport the beams.”
Each beam was 170 feet long and weighed 200,000
pounds, and transporting them from the manufacturer
in Tampa more than 100 miles to Oviedo was no easy
task. Moving the beams required finding the best route,
coordinating with many government agencies, and using
a police escort. The trucks that hauled the beams were
modified with extra wheels to accommodate the massive
weight and the wide, difficult turns.
While engineers were not afraid to stretch the limits of
design with the size of the main span, they opted instead to
go a little “retro” with the support structure for the bridge.
Ayres Associates’ engineers used spread footings, an older
engineering method, for the main column rather than deep
piling. Spread footings, or steel-reinforced pads, distribute
the column load into the soil uniformly and support the
structure.
“Embracing older engineering techniques allowed
easier accommodation of overhead utilities and saved the
County money,” Sunna said. Ultimately, the project came in
about $700,000 under budget; using this technique helped
achieve those savings.
Designers also had to remember the ultimate purpose
TRENDS
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