Inauguration of Eads Bridge on 4 July 1874
Eads Bridge was the world’s first steel-truss bridge, and an engineering marvel.
The Eads Bridge is a combined road and railway bridge over the Mississippi River connecting the cities of St. Louis, Missouri and East St. Louis, Illinois. The bridge is named for its designer and builder, James Buchanan Eads.
In order to accommodate the massive size and strength of the Mississippi River, the Eads Bridge required a number of engineering feats. Perhaps most importantly, it was the first large-scale use of steel as a structural material and initiated the shift from wrought-iron to steel as the default material for large structures. Its foundations were the deepest underwater constructions at the time, at more than 100 feet below water level. They were installed using pneumatic caissons, a pioneering application of caisson technology in the United States and, at the time, by far the largest caissons ever built. Its center arch was the longest rigid span ever built at the time.
The method of constructing the arches, in which they were suspended from temporary wooden towers, is sometimes cited as the first use of the “cantilever principle” for a large bridge. These engineering principles were used for later bridges, including the Brooklyn Bridge, which began construction in 1870.
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Bruno Dursin – Managing Director at Believe in Steel. Bruno has more than 30 years of experience in promoting steel & steel solutions. His clients benefit from his extensive network within the building industry.