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The introduction of wire bridges in Texas was a logical extension of a new
technology developed during the Industrial Revolution. Recent illumination of
their continuous use in Texas from the end of the Civil War to the beginning of
World War II provides insight into the parallel development of the state’s
transportation system in general during that period.
The rapid mechanization of the textile industry in the early 19th century,
specifically development of carding machines to align raw textile fibers using
wire teeth, led to the mass production of high-quality drawn iron wire.
The initial adaptation of this wire to build up catenaries and stays for
cable supported bridges occurred more or less simultaneously near textile
manufactories in eastern Pennsylvania, southern Scotland, and southeastern
France during the decade between 1815-1825. Techniques for fabrication and
analysis of these new wire structures developed rapidly in France from this
period until about 1850.
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Waco Suspension Bridge, 1870 |
The American engineer, Charles Ellet Jr., became interested in wire cable
bridges during a trip to France between 1830 and 1832. He studied a year at the
Ecole des Ponts et Chaussees in Paris, and he made a trip through southern
France where he studied suspension bridges then under construction. Returning to
the United States, he proposed several wire suspension bridges based on the
French model and published a series of pamphlets on the subject beginning in
1839.
In 1842 he completed construction of his first suspension bridge, a 104-m
(342-ft.) span across the Schuylkill River at Fairmont, Pennsylvania. In 1849 he
completed his final suspension bridge, a 308-m (1010-ft.) span over the Ohio
River at Wheeling, Virginia (now West Virginia). The Wheeling Suspension Bridge
was the world’s longest span when it was completed. With Ellet’s achievements
and misfortunes of the French, the impetus for new developments in wire cable
bridges shifted from France to the United States.
Ellet's early accomplishments were eventually superseded by another American
bridge builder, his competitor, John A. Roebling. Roebling’s first suspension
spans were aqueducts over the Allegheny River built for the Pennsylvania Canal
and completed in 1845. Roebling received a patent in 1847 for the method that he
perfected for spinning wire cables in situ. In 1856, he began the last major
structure completed in his lifetime: the Cincinnati Suspension Bridge over the
Ohio River between Ohio and Kentucky, with a 322-m (1057-ft.) main span. When it
opened to the public on December 1, 1866, the Cincinnati Bridge was widely
celebrated as the state of the art in modern bridges. Its celebrity likely
contributed to the introduction of wire cable suspension bridges in Texas.
Note: This web page is adapted from the following paper:
Lisa J. Hart and Charles E. Walker, P.E., "Historic Texas Suspension
Bridges–Part 1: History." In International Engineering History and Heritage
(Houston: American Society of Civil Engineers, 2001)
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