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A majority of West Virginia’s bridges are not even noticed by
motorists passing over them. As an example, the state’s
turnpike averages more than one bridge for every mile, but
motorists probably only see the impressive superstructure of the
Charleston’s Yeager Bridges while ignoring bridges of much
plainer appearance.
When a bridge fails in any
part of the world, however, people do notice. And West Virginia
is no exception.
The state’s
shortest-lived structure was the Sewell Bridge over the New
River, where a ferry had operated as early as 1795. When the
Fayette County Court decided to construct a bridge nearly
three-quarters of a century later, it awarded an $18,500
contract to William N. Page, known as Captain Page because he
once commanded a company of the state militia (now the West
Virginia National Guard).
The bridge was built
during a comparatively dry spell in 1860, when the water in the
river was both low and calm. Long metal pipes, positioned
upright in the river and filled with concrete, served as piers
upon which the bridge was built. Unfortunately, 21 days after
the structure was opened for travel, wet weather arrived. With
the higher water level, the bridge failed, thus achieving a
unique place in history as the structure lasting the shortest
time of any that ever spanned the oldest river on the North
American continent.
A suspension bridge built
in 1851 over the Elk River at Charleston collapsed in December
1904 when one of its anchorages suffered a failure, killing two
people and plunging many others into the icy river.
Yet West Virginia’s most
famous bridge collapse—in December 1967—resulted in safer
bridges for all Americans.
SILVER BRIDGE
So-called by Point
Pleasant-area residents viewing its silvery aluminum paint for
the first time, the Silver Bridge was designed by J.E. Greiner
Company and built by Gallia County Ohio River Bridge Company
(later West Virginia-Ohio Bridge Company) and its subcontractor,
U.S. Steel’s American Bridge Company. A two-lane,
1760-foot-long eyebar suspension bridge with a 700-foot main
span 102 feet above the bottom of the Ohio River channel and two
380-foot anchor spans, it was completed in one year, opening to
traffic on Memorial Day 1928.
Although the original
design had called for conventional wire cables, an eyebar chain
design—bid as an alternate—came in at a lower price. The bridge
was described in the June 20, 1929 Engineering News Record
as “the first of its type in the United States” (another of
the same design, the Hercilio Luz Bridge in Florianopolis,
Brazil, was built in 1924 and is reportedly still in service;
the Silver Bridge’s twin—another toll facility, also known as
the Hiram “Hi” Carpenter Bridge—was constructed 75 miles
upstream at St. Marys in 1928, using different approaches but
the same engineer, contractor, fabricator and shop drawings).
Unlike three
chain-link suspension bridges at Pittsburgh and others
throughout the world, particularly in Europe, the Silver
Bridge’s anchorages were, according to the magazine, “unique (in
their) use of heat-treated eyebar chains, portions of which form
parts of the top chords of the stiffening trusses.” In this
arrangement, each chain link consisted of a pair of bone-shaped
2x12-inch bars, varying in length from 45 to 55 feet by their
position on the bridge, with 11-inch-diameter pins connecting
the links through the “eyes” at the ends of the bars. These
chains constituted the upper chord to a Warren-type stiffening
truss in the seven panels of each side span and 12 panels of the
center span.
Perhaps ominously, the
Engineering News Record article also noted the fact that
it was not possible to make “any adjustments in the chains,
hangers or trusses after erection.”
Following West
Virginia’s purchase of the Hi Carpenter Bridge in 1937 and
removal of its tolls in 1946, the Silver Bridge was bought by
the state for $1.04 million in 1941 and made toll-free ten years
later on December 31.
Inspections, which had
been done by the private owner from 1928 to 1941, were taken
over by the State Road Commission. State standards were
followed during inspections, which were noted in 1959, 1963 and
1964. Following an inspection in 1965, some $30,000 in
recommended repairs were completed. Two more inspections were
done in the summer of 1967, with a final visit by the
Commission’s area maintenance engineer on December 6.
At 5 p.m. on December
15, 1967, eyewitnesses recall, there was a loud gunshot-like
noise and, “folding like a deck of cards” in less than 20
seconds, the entire 1460-foot suspended portion of the Silver
Bridge collapsed into the river, taking with it 32 vehicles and
46 victims, including two whose bodies were never found.
Almost immediately
arrangements were made with a local ferry to take vehicles—which
had averaged 3,500 to 4,000 daily on the bridge, including 20
percent truck traffic—between rapidly prepared landings on the
Ohio and West Virginia shores. A shuttle service began on the
New York Central Railroad Bridge immediately upstream and
vehicles were also detoured 14 miles north to the Pomeroy Bridge
or even further south to a new bridge carrying US 52 over the
river at Huntington.
On February 7, 1968,
with economic losses that were estimated at $1 million a month,
President Lyndon Johnson ordered a federal-state program for
immediate reconstruction. Design on the substructure,
superstructure and approaches was done by three consulting
firms, with the superstructure designer saving precious time by
utilizing preliminary drawings previously prepared for the I-20
Mississippi River bridge at Vicksburg, altered to fit the
topography.
The National
Transportation Safety Board began an investigation immediately,
along with a temporary closure of the Silver Bridge’s twin at
St. Marys.
The Presidential Task
Force on Bridge Safety also looked into the collapse and
conducted a national survey on bridge safety that included
analysis of procedures and standards used to insure the safety
of other bridges throughout the country and development of
recommendations to assure the safety of the public.
On April 6, 1971, the
Safety Board finally issued its determination of the cause of
the collapse—“a cleavage fracture in the lower limb of the eye
of eyebar 330 at joint C13N of the north eyebar suspension chain
in the Ohio side span. The fracture was caused by the
development of a critical-size flaw over the 40-year life of the
structure as the result of the joint action of stress corrosion
and corrosion fatigue.”
Laboratory work
identified the failure sequence as “a brittle fracture of the
lower half of the eye, then a ductile fracture of the upper
half,…resulting (in) pulling…the companion eyebar off the pin
which had connected it with the fractured eyebar.” It concluded
that, “With the north…chain thus broken, the structure’s design
made total collapse…inevitable.”
Noted in the report
were findings that, in 1927, “stress corrosion and corrosion
fatigue were not known to occur in the bridge materials used
under conditions of exposure normally encountered in rural
areas” and that the location of the minute crack “was
inaccessible to visual inspection” and could not have been
detected “by any…method…without disassembly of the eyebar
joint”—a practical impossibility.
Among the Safety
Board’s recommendations to the US Secretary of Transportation
were expanding or beginning research programs aimed at such
areas as identifying susceptible bridge construction materials
and developing new inspection equipment and safeguards in
selecting materials, design and fabrication of future bridges.
Its final recommendation was to “explore alternatives” to assure
that federal bridge safety standards be applied to all highway
bridges (not just the 165,000 on the federal system but the
other 398,000 structures) and “consider proposing a program of
federal-aid funding.”
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