Paul Séjourné

from Wikipedia, the free encyclopedia
Paul Séjourné in old age, in the regalia of the Académie des sciences

Paul Séjourné (born December 21, 1851 in Orléans , † January 15, 1939 in Paris ) was a French civil engineer and railway builder, who was mainly known for his arched bridges with large spans.

Life

Paul Séjourné graduated from the École polytechnique in 1873 and the École Nationale des Ponts et Chaussées in 1876 .

In the following years he worked as an engineer des ponts et chaussées, first in Mende , Lozère department, then in Marmande , Lot-et-Garonne department , where he married, and then in Toulouse . During the construction of various railway lines, he gained recognition by the development of the caisson - foundation for the pillars of the Garonne bridge in Marmande, but especially m with the planning and construction of the bridges of Le Castelet with a wingspan of 41.20, the Viaduct Lavaur in Lavaur with a span of 61.50 m and the bridge at Vielmur-sur-Agout / Sémalens with a span of 50 m. The 33-year-old engineer was therefore allowed to dedicate the bridge at Vielmur / Sémalens to his wife and to christen Pont Antoinette . He published a report on these three bridges in 1886, which, at least in France, was of fundamental importance for the construction of further brick arches.

In 1888 he made a trip to Turkestan as far as Samarkand in what is now Uzbekistan to inspect the Trans-Caspian Railway built by the Russian General Annenkow .

Between 1890 and 1893 he took a leave of absence to build part of the line from Linares to Almería for the French Compagnie de Five-Lilles in Spain .

He then returned to Mende as Ingénieur en Chef of the Lozère department, where he was responsible for the routes from Mende to La Bastide-Puylaurent and outside his department in the northern Massif Central from Bort-les-Orgues to Neussargues-Moissac .

In 1896 he left the civil service to work for the PLM, the Compagnie des chemins de fer de Paris à Lyon et à la Méditerranée as Ingénieur en Chef in Dijon on the further expansion of the railway network . By this time the major lines of the French railway network had long been built. According to the “ Freycinet Plan ”, however, the less important places should also receive rail connections. Corresponding agreements between the state and the major railway companies such as the PLM provided that these would build and operate some of the lines on behalf of the state. Many of these branch lines, which fell under the responsibility of Séjourné, were located in mountainous terrain and therefore required numerous engineering structures such as viaducts, tunnels and retaining walls.

Séjourné's post in Dijon gave him enough time for other projects, such as B. the planning and execution of the Adolphe Bridge, built in Luxembourg from 1899 to 1903 . He also held lectures on masonry bridges at the École Nationale des Ponts et Chaussées from 1901, which he only finished at the age of 72.

In 1909 he was promoted to head of the entire construction department of PLM in Paris and to its deputy director, so that his responsibility expanded to the planning and construction of numerous other railway lines.

Between 1913 and 1916 he published the six volumes of his work Grandes Voûtes ( Great Bridge Arches ), which comprehensively describes the knowledge of brick bridges at the time.

In 1916 he was commissioned by Louis Hubert Lyautey , the first general resident of the Protectorate of French Morocco , to plan the Moroccan railways , which were founded in 1920 as the Compagnie des chemins de fer du Maroc and in which the PLM participated. Séjourné was therefore also active with his PLM planning office for several railway lines in Morocco.

In 1927, at the age of 76, he handed over the design department to his long-time deputy M. Martinet and retired with the title of Honorary Director.

In retirement, he experienced that the PLM was nationalized as a result of the difficult economic situation together with the other large railway companies to form the Société nationale des chemins de fer français and the planning office was closed.

Paul Séjourné died on January 15, 1939 after a long illness at the age of 88 in Paris, where he was buried in the Montmartre cemetery.

Contribution to construction technology

For the construction of stone arches, wooden falsework was erected , on which the complete stone arch was built, which rested with its entire weight on the falsework. This traditional construction method led to an enormous need for wooden planks and beams for larger and wider arches. In addition, the falsework developed into an independent component with its own rules, the behavior of which could hardly be precisely calculated. Séjourné therefore split the broad arch into two narrow arches that were parallel to each other. He also provided for double-layer arches, where initially only the first layer was bricked on the falsework. After removing the falsework, the thin arch formed by the first layer stood independently, carried its own weight and at the same time served as a falsework for the next arch layer. This enabled much lighter and narrower falsework to be used, which could also be removed more quickly and used for the next arches. Furthermore, Séjourné avoided the use of falsework on the ground, which cause enormous costs, especially with high bridge arches, but instead developed a cost-saving demolished falsework that was stabilized with steel cables that could be adjusted using screw spindles. The construction of double-layer bridge arches was already used in ancient Rome, but was forgotten again. It was Séjouné's merit to rediscover and perfect this construction method. To save even more weight, he used a reinforced concrete bridge plate, which was supported by a series of vertical pillars on the narrow arches of the bridge. For example, he was able to produce a 22 m wide bridge slab on two arches, each 3.25 m wide, i.e. 6.50 m together ( Pont des Catalans in Toulouse). These ideas later found their way into the construction of concrete bridges.

Some of his buildings

The Adolphe Bridge was with a wingspan of 84 m at that time by far the largest stone arch bridge in the world and made Séjourné widely known outside France. It consists of two parallel, brick arches and a much wider reinforced concrete bridge panel and became the model for a number of other bridges, some of which were built by Séjouné and others by other designers.

He himself took over the construction elements z. B. at the Pont des Amidonniers (now called Pont des Catalans ), which was built from 1904 to 1907 in Toulouse over the Garonne. Its five wide and flat openings each consist of two parallel, only 3.25 m wide masonry arches that support a reinforced concrete bridge panel 22 m wide.

The Viaduc de Fontpédrouse, Pyrénées-Orientales on the Ligne de Cerdagne , later called Pont Séjourné , built from 1906 to 1908, initially bridges a deeply cut river valley with a 30 m wide pointed arch, on this lower bridge stands the only 2.50 m wide , actual brick viaduct that carries the reinforced concrete slab for the railroad.

The 1908-1912 built under Séjournés line in 103 m above the Oued Rhumel in Constantine , Algeria leading Pont Sidi Rached looks like a copy of the Adolphe bridge, but with a span of 68 m and long bridge spans an independent construction.

The Viaducs de Morez, also completed in 1912, were best known for their widely visible loops with which the railway overcomes the enormous difference in altitude between the Jura and the Morez valley.

The Viaduc de Chanteloube is located on the railway line from Chorges , Hautes-Alpes to Barcelonnette , Alpes-de-Haute-Provence, which began in 1909 but was never completed , and crosses with six main arches and four side arches in a long S-curve with a slight gradient a side valley that was later flooded by the Lac de Serre-Ponçon reservoir . At low tide, the bridge emerges from the reservoir.

The Viaduc des Eaux-salées on the route from Marseille – L'Estaque to Miramas, with its span of 50 m, is an excellent example of Séjourné's bridge construction style, as is the Viaduc de Corbière, which was built on the same line.

The Viaduc de la Recoumène at Le Monastier-sur-Gazeille was part of the planned but never completed Ligne transcévenole from Le Puy-en-Velay , Haute-Loire to Lalevade-d'Ardèche . The 270 m long structure, which runs in a curve, contains 8 round arches with a span of 25 m and a height of 65 m above the Gazeille river .

The Viaduc de L'Escarène is part of the French branch of the Tendabahn, which opened in 1927, from Breil-sur-Roya to Nice .

The Viaduc de la Bevera is also part of the French branch of the Tendabahn. It is unusual in that a steel box girder is supported by a stone arch that is perpendicular to the line and resembles a parabola. Since the line cuts the very narrow valley at an acute angle, this was the cheapest solution. The bridge, which was destroyed in the war, was rebuilt true to the original in 1962, albeit with a concrete arch.

The 180 m long and 55 m high Viaduc de la Bonne near Valbonnais and the 260 m long and 110 m high Viaduc de la Roizonne near La Mure are located on the former route from La Mure to Corps in the Isère department , which was opened in 1928. The two bridges are among the very last large stone arch bridges in France, if not all of Europe.

  • Pont Antoinette, Vielmur-sur-Agout / Sémalens, Tarn (1884)

  • Adolphe Bridge, Luxembourg (1903)

  • Adolphe Bridge

  • Adolphe Bridge

  • Pont des Amidonniers / Pont des Catalans, Toulouse (1907)

  • Pont des Amidonniers / Pont des Catalans

  • Pont Séjourné, Fontpédrouse, Pyrénées-Orientales (1908)

  • Pont Séjourné

  • Pont Sidi Rached

  • Viaducs de Morez, Jura (1912)

  • Viaduc de Chanteloube, near Gorges, Hautes-Alpes (1909-1935)

  • (1914)

  • Viaduc de Corbière, Marseille-L'Estaques (1915)

  • Viaduc de la Recoumène, near Monastier-sur-Gazeille (1925, never used)

  • Viaduc de L'Escarène on the Tendabahn in France (1927)

  • Viaduc de la Bevera on the Tendabahn in France (1927/1962)

  • Viaduc de la Bevera

  • Viaduc de la Bevera

  • Viaduc de la Bonne, near Valbonnais, Isère (1928)

  • Viaduc de la Bonne

  • Viaduc de la Roizonne, near La Mure, Isère (1928)

Honors

On July 3, 1886 Paul Séjourné at the age of only 35 years, the Order of was Chevalier de la Legion d'Honneur awarded for the construction of various railway bridges with large span that can be both for its monumental character and called for its construction methods as a model .

In 1906 he was the first to receive the prize, donated by the General Inspector of the Ponts et Chaussées Rouville, for outstanding performance in the construction of brick bridges.

In 1918 he was awarded the Prix Caméré by the Académie des sciences, and the following year, although he had not worked in the civil service for a long time, he was appointed Inspecteur Général des Ponts et Chaussées and Grand Officier de la Légion d'Honneur.

On December 8, 1924 he was elected a member of the Académie des Sciences .

Streets and squares in Toulouse, Perpignan, Béziers, Luxembourg and Paris bear his name.

Publications

  • Construction of the ponts du Castelet, de Lavaur et Antoinette . Annales des Ponts et Chaussées 1886, II. Volume XII, pp. 409-549. Digitized on BnF Gallica
  • Grandes Voûtes , Tôme I - VI, Imprimerie Vve Tardy-Pigelet et fils, Bourges, 1913-1916
  • Comment aujourd'hui on projette et on construit les grandes voûtes en maçonnerie . Annales des Ponts et Chaussées 1931

Individual evidence

  1. ↑ Garonne Bridge near Marmande 44 ° 30 ′ 7.9 ″  N , 0 ° 8 ′ 20.9 ″  E
  2. ^ Bridge from Le Castelet on the Tarascon-sur-Ariège route to Ax-les-Thermes 42 ° 44 ′ 23.4 ″  N , 1 ° 47 ′ 25 ″  E
  3. ↑ Lavaur bridge on the Montauban - Castres route 43 ° 42 ′ 11.8 ″  N , 1 ° 49 ′ 27 ″  E
  4. ↑ Bridge from Vielmur-sur-Agout / Sémalens ( Pont Antoinette ) on the Montauban - Castres route 43 ° 36 ′ 44.9 ″  N , 2 ° 6 ′ 39.8 ″  E
  5. ↑ Saint-Jean-de-Losne to Lons-le-Saunier, Paray-le-Monial to Lozanne, Dijon to Épinac, Morez to Saint-Claude, Le Puy to Langogne, Brioude to Saint-Flour
  6. ↑ Anduze to Saint-Jean-du-Gard (completion), Aigues-Mortes to Grau-duRoi (completion), Moûtiers to Bourg-Saint-Maurice, Riom to Châtel-Guyon, Vichy to Cusset, Miramas to L'Estaque, Prasne to Vallorbe, Monéteau to Saint-Florentin, Nice to Sospel and Breil-sur-Roya, Riom to Vichy, La Ferté-Haute-rive to Gannat, Le Puy to Lalevade-d'Ardèche and Chorges to Barcelonnette
  7. ↑ Adolphe Bridge 49 ° 36 ′ 29 ″  N , 6 ° 7 ′ 37.6 ″  E
  8. ↑ Pont des Catalans 43 ° 36 ′ 12.1 ″  N , 1 ° 25 ′ 40.9 ″  E
  9. ↑ Pont Séjourné 42 ° 31 ′ 4 ″  N , 2 ° 12 ′ 13.5 ″  E
  10. ↑ Pont Sidi Rached 36 ° 21 ′ 44.9 ″  N , 6 ° 36 ′ 49.3 ″  E
  11. ↑ Viaducs de Morez 46 ° 31 '48 "  N , 6 ° 1' 19.5"  E
  12. ↑ Viaduc de Chanteloube 44 ° 30 '39.2 "  N , 6 ° 18' 26.4"  E
  13. ↑ Viaduct des Eaux-salées 43 ° 19 '57.8 "  N , 5 ° 11' 6.8"  O
  14. ↑ Viaduc de Corbière 43 ° 21 '27.2 "  N , 5 ° 17' 17.5"  E
  15. ↑ Viaduct la Recoumène 44 ° 55 '52.3 "  N , 4 ° 1' 3.1"  O
  16. ↑ Viaduc de L'Escarène 43 ° 50 '12.4 "  N , 7 ° 21' 20.7"  E
  17. ↑ Viaduc de la Bevera 43 ° 53 '11.2 "  N , 7 ° 29' 10.2"  E
  18. ↑ Viaduc de la Bonne 44 ° 53 ′ 45.5 ″  N , 5 ° 51 ′ 29.5 ″  E
  19. ↑ Viaduct la Roizonne 44 ° 54 '50 "  N , 5 ° 49' 45.2"  O
  20. ↑ List of former members of the Académie des sciences ( Memento of the original from May 1, 2012 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / www.academie-sciences.fr
  21. ↑ Listing in Google maps

Web links

personal data
SURNAME Séjourné, Paul
BRIEF DESCRIPTION French civil engineer
DATE OF BIRTH December 21, 1851
PLACE OF BIRTH Orleans
DATE OF DEATH January 15, 1939
Place of death Paris