Garabit viaduct
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The Garabit Viaduct (Viaduc de Garabit in French) is a railway arch bridge
Arch bridge
An arch bridge is a bridge with abutments at each end shaped as a curved arch. Arch bridges work by transferring the weight of the bridge and its loads partially into a horizontal thrust restrained by the abutments at either side...
spanning the Truyère
Truyère
The Truyère is a 167 km long river in south-western France, right tributary of the Lot River. Its source is in the south-western Massif Central, north of Mende. It flows generally west through the following départements and towns:...
river near Ruynes-en-Margeride
Ruynes-en-Margeride
Ruynes-en-Margeride is a commune in the Cantal department in south-central France.-Population:-References:*...
(Fr), Cantal
Cantal
Cantal is a department in south-central France. It is named after the Cantal mountain range, a group of extinct, eroded volcanic peaks, which covers much of the department. Residents are known as Cantaliens or Cantalous....
, France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
, in the mountainous Massif Central
Massif Central
The Massif Central is an elevated region in south-central France, consisting of mountains and plateaux....
region. The bridge was constructed between 1880 and 1884 by Gustave Eiffel
Gustave Eiffel
Alexandre Gustave Eiffel was a French structural engineer from the École Centrale Paris, an architect, an entrepreneur and a specialist of metallic structures...
, with structural engineering
Structural engineering
Structural engineering is a field of engineering dealing with the analysis and design of structures that support or resist loads. Structural engineering is usually considered a specialty within civil engineering, but it can also be studied in its own right....
by Maurice Koechlin
Maurice Koechlin
Maurice Koechlin was a French-Swiss structural engineer.-Life:Born in Buhl, Haut-Rhin, he studied at the lycée in Mulhouse then at the Swiss Federal Institute of Technology under Carl Culmann....
, and was opened in 1885. It is 565 m in length and has a principal arch of 165 m.
Eiffel and his bridge
The French recession of 1864 prematurely ended Eiffel's tenure at the General Railway Equipment Company, but he used the misfortune to begin independent consulting and eventually, his own engineering firm. Opportunity again came for Eiffel during the late 1870s when European railways attempted to grid the continent. Particularly in France, where a vast mountain range suffocated the southern region from any locomotive transport, Eiffel thrust himself to the forefront of the industry and cemented his place as an engineering legend through his efforts in the Massif Central: home to the wide and windy Garabit Valley.The undertaking was daunting. In 1878, Eiffel was asked by Leon Boyer to bridge the valley, with a line 120 metres (400 ft) over the Truyère River. Boyer believed this would be considerably less expensive than taking the railway line around or down through the valley. Eiffel accepted the challenge and succeeded because of his recent experience on the very similar Douro bridge
Maria Pia Bridge
The Maria Pia bridge , commonly known as Ponte Dona Maria, is a railway bridge built in 1877 by Gustave Eiffel in Porto, Portugal...
. To negate the wind, Eiffel instantly discarded precedents of solid beam construction, as he surmised that “it would be very heavy and the beams would rattle in the wind”. Instead, he adopted the concept of truss
Truss
In architecture and structural engineering, a truss is a structure comprising one or more triangular units constructed with straight members whose ends are connected at joints referred to as nodes. External forces and reactions to those forces are considered to act only at the nodes and result in...
es or “a series of open triangles” to assuage wind force that “would blow right through them”. Truss work also provides stability when loads are applied through the theory of tension and compression that states force is exerted on the diagonal and vertical segments causing them to resist one another. Eiffel also improved upon his Douro design, adopting the same two-hinged crescent-arch form but employing an arch visually separated from the thin horizontal girder. The Garabit Viaduct’s arches were engineered to have support hinges, allowing the crescent shape to widen. This method both simplified calculations and improved resistance to wind loads.
When it opened with a single track in November 1885, the Garabit Viaduct was 565 metres (1853 ft) long and weighed 3587 tons. The overall project cost was 627,400 USD. Even more impressive was the actual deflection
Deflection (engineering)
In engineering, deflection is the degree to which a structural element is displaced under a load. It may refer to an angle or a distance.The deflection distance of a member under a load is directly related to the slope of the deflected shape of the member under that load and can be calculated by...
, which was measured at 8 millimetres, a figure precisely anticipated by Eiffel’s calculations. The bridge was also, for many years, the highest in the world.
Until 11 September 2009, only one regular passenger train per day in each direction used to pass over the viaduct - a Corail
Corail (train)
Corail is the name given to a class of passenger rail cars of the SNCF that first entered commercial service in 1975. When introduced, Corail carriages featured air-conditioning, and superior levels of comfort, suspension and sound-proofing than previous InterCity carriages and gave arguably the...
route from Clermont-Ferrand
Clermont-Ferrand
Clermont-Ferrand is a city and commune of France, in the Auvergne region, with a population of 140,700 . Its metropolitan area had 409,558 inhabitants at the 1999 census. It is the prefecture of the Puy-de-Dôme department...
to Béziers
Béziers
Béziers is a town in Languedoc in southern France. It is a sub-prefecture of the Hérault department. Béziers hosts the famous Feria de Béziers, centred around bullfighting, every August. A million visitors are attracted to the five-day event...
. On that date, the viaduct was closed as cracks were discovered in one of the foundation piles. It reopened one month later after a safety inspection and was in service with a speed limit of 10 km/h (6 mph) for all traffic.
On 15 June 2011, the Garabit closed for extensive work. It is due to reopen on 15 December 2011. During the works, the train from Béziers
Béziers
Béziers is a town in Languedoc in southern France. It is a sub-prefecture of the Hérault department. Béziers hosts the famous Feria de Béziers, centred around bullfighting, every August. A million visitors are attracted to the five-day event...
to Clermont-Ferrand
Clermont-Ferrand
Clermont-Ferrand is a city and commune of France, in the Auvergne region, with a population of 140,700 . Its metropolitan area had 409,558 inhabitants at the 1999 census. It is the prefecture of the Puy-de-Dôme department...
terminates at St Chély d'Apcher and a bus continues to Clermont-Ferrand. There is an excellent view of the Garabit viaduct from the bus.
Garabit Viaduct in fiction
Garabit Viaduct was used to represent the condemned "Cassandra Crossing" bridge in the 1976 film The Cassandra CrossingThe Cassandra Crossing
The Cassandra Crossing is a 1976 British disaster film directed by George Pan Cosmatos and starring Richard Harris, Ava Gardner, Sophia Loren, Martin Sheen, Burt Lancaster, Lee Strasberg and O. J. Simpson.-Plot:...
. In the film the Cassandra Crossing has been unused and derelict for 30 or 40 years and is considered dangerous, enough so that people living nearby moved away fearing it could collapse.
In 1964, French director Henri-Georges Clouzot shot The Inferno (L'Enfer) starring Serge Reggiani
Serge Reggiani
Serge Reggiani was an Italian-born French singer and actor. He was born in Reggio Emilia, Italy and moved to France with his parents at the age of eight...
and Romy Schneider
Romy Schneider
Romy Schneider was an Austrian-born German film actress who also held French citizenship.-Early life:Schneider was born Rosemarie Magdalena Albach in Nazi-era Vienna, six months after the Anschluss, into a family of actors that included her paternal grandmother Rosa Albach-Retty, her Austrian...
at the nearby Hotel Garabit (renamed Hotel du Lac for the movie) and on the lake. The film was never completed after disputes between Clouzot and key actors and crew and Clouzot himself suffering a heart attack.
Added pressure came from a deadline after which an electricity company planned to drain the lake to generate power at a nearby dam, also used as a backdrop for the stillborn movie.
The saga was covered in a documentary screened in June 2010 by Sky Arts 2 in the UK.