Eiffel’s masterpiece in bridge building (but with a little help from Léon).
The Garabit viaduct is a French railway viaduct, allowing the crossing of the Truyère gorges. It is located in the Cantal department in the Auvergne-Rhône-Alpes region. The viaduct was designed by the engineer Léon Boyer, who entrusted its completion and construction to Gustave Eiffel and his company.
Photo: CC BY-SA 3.0, Link
Construction began in January 1880, and the viaduct was commissioned on 10 December 1888. This ambitious metal structure reaches 122 m above the river and was the highest viaduct in the world of his time.
Photo: Highway Engineering Discoveries posted
The Garabit viaduct consists of a 565 m long metal deck resting on five wrought iron pillars of varying heights, 10 spans and 3 decks. The three spans above the lowest part of the valley form the arch with a span of 165 m and a height of 52 m. The steel section is framed by two masonry access viaducts to the north and south, 46 m and 71 m respectively.
Photo: Giacomo Coppi, Link
For this crossing, it was impossible to use a suspension bridge because of the risk of oscillations, and it was impossible at the time to envisage pillars over 65 m high. Léon Boyer was inspired by the example of the Maria Pia viaduct over the Douro (Porto).
Source: toureiffel.paris
It took approx. 3,250 tons of wrought iron and 678,768 rivets to build the structure. Most of the rivets were already installed at the factory, in Levallois-Perret, to prefabricate large components which were then sent to the final assembly site. This is exactly the same technology that was to be used for the Eiffel Tower.
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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.
