bridge fails: famous bridge collapses due to corrosion
TRANSCRIPT
Famous Bridge CollapsesDue to Corrosion
Robert Heidersbach
If this is the first time you’re seeing the
word corrosion, you will be surprised with
how important this term can be for your
everyday life! Essentially, corrosion is the
deterioration of materials like copper or
steel over time. It’s a big problem for
engineers and other architects who
frequently use metal products in their
structures, because corrosion can be a
safety hazard! To see what I mean, take a
look at the following bridge collapses that
occurred due to corrosion.
Lowe's
Motor
Speedway
When the NASCAR Winston stock car race
ended, hundreds of pedestrians made their
way back to the parking lot by crossing a
pedestrian bridge that overlooked U.S. Route
29 in North Carolina. As they were making their
way across, the concrete and steel walkway
snapped in half, and pedestrians fell to the
highway below. The bridge collapse injured
107 people and 13 were in critical condition.
Lowe's
Motor
Speedway
After an inspection, it was determined that all
11 steel cables that were holding the bridge
together were corroded, and the bridge
bustled under the weight. The corrosion was
caused by too much calcium chloride, an
inorganic salt compound that’s highly
corrosive to steel, mixed into the grout that
cemented the bridge’s steel cables in place.
The compound is acceptable in small
amounts, but the construction company that
built the bridge used about 40 times more
calcium chloride than what was regulated!
Lowe's
Motor
Speedway
Nearly 50 lawsuits were filed against the
speedway and the construction company with
settlements of millions of dollars — just to
expedite the drying process.
Silver
Bridge
The U.S. Highway 35 bridge, nicknamed the
“Silver Bridge” since it was the country’s first
aluminum-painted one, was a major
transportation route between West Virginia
and Ohio. During rush hour traffic, the bridge
suddenly collapsed into the Ohio River and 75
vehicles were submerged. The tragedy killed
46 people and seriously injured nine.
Silver
Bridge
The cause of failure was from stress corrosion
and corrosion fatigue. Years before the
collapse, a tiny crack appeared in a suspension
chain on the bridge, and the crack grew bigger
as time went on. However, it went unnoticed
by bridge inspectors because technology did
not allow inspectors to see the crack.
Silver
Bridge
Constructed in the mid 1920s, the steel used
for the bridge was not known for being
susceptible to corrosion, so disaster was
inevitable. In addition, the bridge was
designed for Model-T Ford, which had an
approximate weight three times less than cars
in 1967!
Kinuza
Bridge
You would never believe it, but this 3,300-ton,
half-mile-long railroad bridge in north-central
Pennsylvania was once deemed the Eighth
Wonder of the World. The bridge collapsed
when strong thunderstorms with 80 mph
winds came through the region and sent most
of the bridge crashing into the gorge below.
Kinuza
Bridge
Built from iron 1882 and reconstructed using
steel in 1900, the bride fell into disrepair and
became covered in rust. Its cracked foundation
turned orange with age, and its supportive
columns became weak and shed rust flakes
everywhere. It was deemed such a safety
hazard that state officials closed the bridge to
train and pedestrian traffic because they
feared strong winds could easily topple it.
Robert “Bob” Heidersbach is the author of Metallurgy and Corrosion
Control in Oil and Gas Production. The book is based on Robert’s
experience teaching new engineers that need to understand metallurgy
and corrosion control in the oil industry. He is currently in the process of rewriting and updating the publication, and welcomes any suggestions
about how to improve the book. In his spare time, Bob enjoys kayaking, biking and traveling.