Bridges show their age raising the need for
proper upkeep
Tnemec Company identifies coating systems for bridge structures that help
withstand the test of time and can be applied under full-containment in
order to minimize downtime.
The aging of America’s 590,000 bridges has led to increased maintenance and rehabilita-
tion funding in recent years, with
even higher levels of future spend-
ing anticipated to sustain their
health and safety. “While 50 years
ago the nation faced a historic peri-
od of bridge construction, today it
faces a historic period of bridge
repair and reconstruction,” accord-
ing to the American Association of
State Highway and Transportation
Officials (AASHTO) in its report
titled “Bridging the Gap.”
The report credited state depart-
ments of transportation with keeping
the nation’s network of bridges safe
through ongoing inspections, the use
of improved materials, and “inge-
nious repairs.” At the same time, the
report acknowledged, “A significant
new investment and national com-
mitment is necessary to protect these
invaluable assets.”
Special attention is being given to
structures that are more than 50 years
old and heavily traveled, which AASH-
TO has labeled, “Baby Boomer
Bridges.” Falling into this category is
the Maurice J. Tobin Memorial Bridge,
which stretches across the Mystic River
to connect the Charlestown section of
Boston with Chelsea. Currently operat-
ed by the Massachusetts Department
of Transportation, the three-span, can-
tilevered truss bridge first opened to
traffic in 1950.
At approximately 2 1/4-miles long,
the bridge is the largest in New
England and the first in Massachusetts
Bridges that are more than 50 years old—“Baby Boomer Bridges”—like Boston’s
Tobin Bridge above, are part of an increased effort to repair and reconstruct aging
bridges in the U.S.
to use a new, high-tech structural monitoring system that uses wireless sensors attached to various areas of the
bridge. A continuous flow of data from
these sensors will provide engineers
with real-time information on loads,
stresses, environmental conditions and
corrosion on the bridge. When fully
operational, this “smart bridge technology” will enable engineers to address
any issues immediately.
Engineers also follow a proactive
schedule of bridge inspections and a
carefully phased recoating and re-
decking program to keep the bridge
in good condition. Bridge mainte-
nance has been an ongoing priority
since the late 1970s, when the first
lead abatement project in the country
was initiated by the Massachusetts
Port Authority (Massport) engineer-
ing department, which operated the
bridge at that time. “I started my
career on that bridge as a paint
inspector,” recalled Larry Mitkus,
who is currently a coating consultant
with Tnemec Company. “I was on that
bridge for three straight years, which
is why I know it so well.”
Over the years, Mitkus has contin-
ued his involvement with the Tobin
Bridge, specifying high-performance
coating systems for major renovation
projects, including an on-ramp for a
toll plaza that was recoated in 2000.
“They can’t recoat the entire bridge
at once because of its size, so projects
are divided under different con-
tracts,” Mitkus explained. “The speci-
fied color is a federal standard green,
