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IDOT USES HIGH-PERFORMANCE STEEL DEVELOPED AT NORTHWESTERN
EVANSTON, Ill. ---
The Illinois Department of Transportation
(IDOT) announced the completion of a new bridge in Lake Villa, Lake
County,
constructed with a groundbreaking type of high-performance steel
developed by
engineering researchers at Northwestern University.
About 500 tons of the
copper alloy steel, known as ASTM A710 Grade
B high-performance structural steel, was used in constructing the
430-foot span
that carries IL Rt. 83 over the Canadian National Railroad tracks.
While some
landscaping work remains, the bridge opened in its normal traffic
pattern Aug.
30.
“IDOT is
excited about the possibilities presented by this new
type of cost-efficient, high-performance steel developed right here in Illinois,”
said IDOT
Secretary Timothy W. Martin. “Not only is this steel strong,
tough and easy to
fabricate, but it withstands the elements better than typical steel,
meaning it
doesn't have to be painted. This makes construction easier and will
significantly reduce long-term maintenance costs.”
IDOT is in the
process of applying to the American Society for
Testing and Materials (ASTM) and the
American Association of State
Highway and
Transportation Officials (AASHTO) to have this steel designated as
standard for
bridge construction.
The only previous use
was in the rehabilitation of the Poplar St.
Bridge over the Mississippi River
in the Metro
East area.
The steel has a
strength of 70,000 pounds per square inch (psi)
compared with 50,000 psi in commonly used structural steel. It is also
easy to
weld, and tests have shown it has high-impact toughness at low
temperatures. In
addition, the high copper content gives the alloy much better
resistance to
atmospheric corrosion than other high-performance steels.
“We
developed this steel nine years ago and application has been a
long time in coming,” said Morris E. Fine, professor emeritus
of materials
science and engineering at Northwestern University,
who developed
the new alloy with his colleague Research Professor Semyon Vaynman and
with key
support from Northwestern's Infrastructure Technology Institute (ITI).
“This
steel is cost-effective because its processing is cheaper than
competing
structural steels of the same strength, its weathering resistance is
best, and
it's easier to weld.”
“We are
delighted to see our steel used in this new bridge and
hope that the steel will be used in other bridges in Illinois
as well as in other states,” said
Vaynman, research professor of materials science and engineering at
Northwestern.
“For more
than a half-century, Professor Fine has been one of the
seminal leaders in materials science engineering worldwide,”
said David Schulz,
director of ITI. “The Infrastructure Technology Institute is
pleased and proud
to have supported his team's development of the high-strength steel
employed in
the Route 83 bridge. We look forward to continuing to help him 'push
the
envelope' of ever-stronger and more economical steels.”
The Lake
Villa
bridge was
constructed by Dunnet Bay Co. with a contract value of $5.75 million.
The
bridge designer was Graef Schloemer and Associates of Chicago. The
steel was
produced by Mittal Steel USA in Coatesville,
Pa.,
and fabricated at Industrial Steel Construction in Gary.
IDOT received
federal funds to pay for the steel through the Federal Innovative
Bridge
Research Fund.
The project was
supervised for IDOT by Resident Engineer Mario
Biondolillo. Also playing a key role for IDOT on the project was Chris
Hahin,
the principal investigator and metallurgical engineer for the
department. IDOT
estimates not having to paint the steel saved $300,000. The new bridge
replaced
a structure dating from 1929. Construction was carried out in stages in
order
to keep traffic flowing on Rt. 83.
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