Links
The official web site of the
Mackinac Bridge
Mackinac
Bridge - information & great photos
BridgePros Video Review
The Mackinaw Bridge
Museum
Mackinac Bridge
& straits of Mackinac Page
Mackinac Bridge - Live
web cam
Mackinac Bridge -
history page
Michigan D.O.T. page
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PROJECT OVERVIEW:
On July 1, 1888, the board of directors of the famous Grand Hotel at
Mackinac Island held their first meeting and the minutes show that
Commodore Cornelius Vanderbilt said: " We need a bridge
across the Straits." The great Firth
of Forth Bridge in Scotland was under construction then and completed
in 1889. Many years after this meeting a citizens' committee
was established to obtain legislation to create a bridge authority.
In 1950 the legislation was enacted, but it limited the newly created
Authority to determine feasibility only. The Authority consulted
with three of the world's experts in long span bridge engineering and
traffic consultation for advice on physical and financial
feasibility. The bridge project officially began on May 7 & 8,
1954, at St. Ignace and Mackinaw City. The project employed as many
as 3500 men at the bridge site. The massive 5 mile long bridge was the
longest suspension bridge in the world when completed. With a main
span length of 3800 ft. and towers that rose 552 ft. in the air, this
project was was a monumental signature of the great designer, Dr. David B.
Steinman. The center span of 3,800 ft. was the second-longest in the world, but the overall length of suspended deck - the main span and the two side
spans - was the longest ever, and remained so until 1998. The bridge was opened to traffic, according to the
schedule on November 1, 1957.
Facts and Figures:
| Total Length of Bridge (5
Miles) |
26,372 Ft. |
| Length of Suspension Bridge
(including Anchorages) |
8,614 Ft. |
| Length of Main Span (between
Main Towers) |
3,800 Ft |
| Height of Main
Towers above Water |
552
Ft. |
| Maximum Depth of
Water at Midspan |
295
Ft. |
| Underclearance
at Midspan for Ships |
155
Ft. |
| Total Length of
Wire in Main Cables |
42,000
Miles |
| Maximum Tension
in Each Cable |
16,000
Tons |
| Weight of Cables |
11,840
Tons |
| Diameter of Main
Cables |
24
1/2 Inches |
| Total Concrete
in Bridge |
466,300
Cu. Yds. |
| Total Number
of Steel Rivets |
4,851,700 |
| Total, at
the Bridge Site |
3,500 |
| Total Number
of Engineers |
350 |
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