Page 417 - Challenges in Corrosion Costs Causes Consequences and Control(2015)

BRIDGES 395

Navy-related problems may be attributed more to the complexity of modern
military systems than to cost cutting. This problem may become significant when
the cuts to defense expenses are enforced (48).

5.12 THE AUTOMOBILE INDUSTRY

Corrosion of automobiles is well documented (49–51). Environmental factors such as
the deicing salts on the roads and temperature fluctuations have profound effects on
automobiles. The cars are expected to survive the grinding effect of gravel, offer com-
fortable protection to the passengers, should be easily and economically repairable
on damage with a reasonable service life.
The total cost of corrosion of personally owned automobiles was determined to
range from $6 to $14 billion and avoidable costs were estimated to range between
$2 and 8 billion. The automobile sector had a significantly higher cost than any other
sector, and the cost of this sector was the single most significant driving factor in
estimating the total corrosion cost for the entire United States.
A code for Canada in 1981 specified: (i) a car body should last 1.5 years or
60,000 km before suffering cosmetic corrosion, 5 years (200,000 km) for perforation
corrosion, and 6 years (240,000 km) for structural corrosion. The code projected
for North America in 1990 was to have no cosmetic in 5 years and no perforation
corrosion in 10 years. These code requirements resulted in the use of precoated steel,
especially galvanized steel, which in 1993 satisfied the requirements (52).
In 1981, about 3 million passenger cars and commercial vehicles were being
scrapped in Europe because of three causes: accidents, obsolescence, and corrosion.
McArthur showed a correlation between the number of serious injuries suffered in
road accidents and the age as well as the amount of corrosion of the vehicle (53).
A corroded vehicle was less able to absorb the energy of impact than that of a new
vehicle. The average life of a motor car has increased over the years since the auto
industry had at last reacted to the public demand for more corrosion protection.
Rust proofing treatments of cars have not been very successful, and the Office of
the Attorney General of New York State claimed that consumers were defrauded of
$11 million annually because of poor quality rust treatments.

5.13 BRIDGES
In spite of the tendency to rust, iron either alone or as reinforcement in concrete has
been the basis of civil engineering projects since the world’s first iron bridge was con-
structed over River Severn at Coalbrookdale in England by Abraham Darby in 1780.
Many wrought iron bridges performed well with modest but regular maintenance.
The Royal Albert Bridge at Saltash, Cornwall, built in 1859 by Brunel to carry
a main railway line across the River Tamar between Devon and Cornwall is free
from corrosion and has been given a clean bill of health until 2035. Brunel’s other
bridges are Clifton Suspension Bridge and Telford’s Menai Straits Bridge, a sus-
pension bridge, have stood the test of time. The Telford Bridge originally opened