Joseph Chaley (1795 – April 15, 1861) was a French

civil engineer A civil engineer is a person who practices civil engineering – the application of planning, designing, constructing, maintaining, and operating infrastructure while protecting the public and environmental health, as well as improving existing ...

and a pioneer designer of

suspension bridge A suspension bridge is a type of bridge in which the deck (bridge), deck is hung below suspension wire rope, cables on vertical suspenders. The first modern examples of this type of bridge were built in the early 1800s. Simple suspension bridg ...

s in the 19th century. He was a medical officer in the army before becoming a bridge designer. Chaley pioneered the construction of suspension bridge cables by bringing together individual wire strands in mid-air, a technique later known as aerial spinning. Previously, the entire cable had been bound together before lifting into place, but Chaley's system, inspired by the ideas of

Louis Vicat Louis Vicat (31 March 1786, Nevers – 10 April 1861, Grenoble) was a French engineer. He graduated from the École Polytechnique in 1804 and the École des Ponts et Chaussées in 1806. Vicat studied the setting of mortars and developed his own ...

, allowed considerably longer cables to be erected at less cost.Peters, Tom F., ''"Transitions in Engineering: Guillaume Henri Dufour and the Early 19th Century Cable Suspension Bridges"'', Birkhauser, 1987, He built the Grand Pont Suspendu at

Fribourg , neighboring_municipalities= Düdingen, Givisiez, Granges-Paccot, Marly, Pierrafortscha, Sankt Ursen, Tafers, Villars-sur-Glâne , twintowns = Rueil-Malmaison (France) , website = www.ville-fribourg.ch , Location of , Location of () () o ...

in 1834, a world record-breaking span of 273m, only overtaken 16 years later by

Charles Ellet Jr. Charles Ellet Jr. (1 January 1810 – 21 June 1862) was an American civil engineer from Pennsylvania who designed and constructed major canals, suspension bridges and railroads. He built the Wheeling Suspension Bridge, the longest suspension ...

's 308m span

Wheeling Suspension Bridge The Wheeling Suspension Bridge is a suspension bridge spanning the main channel of the Ohio River at Wheeling, West Virginia. It was the largest suspension bridge in the world from 1849 until 1851. Charles Ellet Jr. (who also worked on the Niag ...

. Chaley had previously worked with

Marc Seguin Marc Seguin (20 April 1786 – 24 February 1875) was a French engineer, inventor of the wire-cable suspension bridge and the multi-tubular steam-engine boiler. Early life Seguin was born in Annonay, Ardèche to Marc François Seguin, the fou ...

's brother Jules on the

Tarascon Tarascon (; ), sometimes referred to as Tarascon-sur-Rhône, is a commune situated at the extreme west of the Bouches-du-Rhône department of France in the Provence-Alpes-Côte d'Azur region. Inhabitants are referred to as Tarasconnais or Tarasc ...

- Beaucaire Bridge (1828) and also the

Chazey-sur-Ain Chazey-sur-Ain (, literally ''Chazey on Ain'') is a commune in the Ain department in eastern France. Population See also *Communes of the Ain department The following is a list of the 393 communes of the Ain department of France. The ...

Bridge (1829). Chaley first presented a proposal for the Grand Pont Suspendu in February 1830, and was awarded the contract in June of that year. His estimated cost of less than 300,000 florins was well below other competitors, including

Guillaume Henri Dufour Guillaume Henri Dufour (15 September 178714 July 1875) was a Swiss military officer, structural engineer and topographer. He served under Napoleon I and held the Swiss office of General four times in his career, firstly in 1847 when he led the ...

. Chaley's bridge was supported on four main cables (two per side), each consisting of 1056

wire Overhead power cabling. The conductor consists of seven strands of steel (centre, high tensile strength), surrounded by four outer layers of aluminium (high conductivity). Sample diameter 40 mm A wire is a flexible strand of metal. Wire is c ...

s each 3.08mm in diameter. It carried 2000 people on its opening day. It was replaced in 1923 by a

reinforced concrete Reinforced concrete (RC), also called reinforced cement concrete (RCC) and ferroconcrete, is a composite material in which concrete's relatively low tensile strength and ductility are compensated for by the inclusion of reinforcement having hig ...

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. A viaduct ...

. Chaley's other suspension bridges include the 227m Pont du Gottéron (1840); and a 64m span at Collomby in

Valais Valais ( , , ; frp, Valês; german: Wallis ), more formally the Canton of Valais,; german: Kanton Wallis; in other official Swiss languages outside Valais: it, (Canton) Vallese ; rm, (Chantun) Vallais. is one of the cantons of Switzerland, 26 ...

(1840). He collaborated with Bordillon on the Basse-Chaîne Bridge at

Angers Angers (, , ) is a city in western France, about southwest of Paris. It is the prefecture of the Maine-et-Loire department and was the capital of the province of Anjou until the French Revolution. The inhabitants of both the city and the prov ...

, completed in 1839. This bridge collapsed in 1850 killing 226 soldiers, a major setback to suspension bridge construction in France and beyond. His only bridge still in existence is the 121m suspension bridge at Corbières (1837).

External links

References

{{DEFAULTSORT:Chaley, Joseph 1795 births 1861 deaths French civil engineers 19th-century French inventors Bridge engineers