View source for Charenton Metro-Viaduct

{{Short description|Girder bridge in France}}
{{Use dmy dates|date=January 2024}}

{{Infobox Bridge
| bridge_name = Charenton Metro-Viaduct
| image = Charenton - viaduc metro 8 renove - septembre 2013.jpg
| caption = The viaduct as seen from Maisons-Alfort in 2013, after its renovation.
| coordinates = {{Coord|48|49|00|N|02|25|07.27|E|display=inline,title}}
| crosses = [[Marne (river)|Marne]]
| locale = France, [[Île-de-France]] region, [[Val-de-Marne]] department, [[Charenton-le-Pont]] and [[Maisons-Alfort]] communes.
| location = {{Location map|France
|width = 200
|alt = Pont du Bonhomme
|lat_deg = 48
|lon_deg = 2
}}
| official_name = Charenton Metro-Viaduct
| owner = [[RATP Group]]
| design = [[Girder bridge]]
| material = Steel
| length = 199 m
| width = 
| mainspan = 55.5 m
| clearance = 
| below = 
| built = 1968–1969
| open = 19 September 1970
| closed = 
| traffic = [[Paris Métro Line 8]]
| mapframe = yes
| mapframe-switcher = 
| map_cue = 
| map_image = 
| map_text = 
| map_width = 
}}The '''Charenton Metro-Viaduct''' is a railroad [[girder bridge]] located in the French department of [[Val-de-Marne]] in the [[Île-de-France]] region. It links the communes of [[Charenton-le-Pont]] and [[Maisons-Alfort]], crossing the [[Marne (river)|Marne]] river, as well as the [[A4 autoroute]] and [[103 departmental road]]. First put into operation in 1970, the viaduct is used by trains on [[Paris Métro Line 8|line 8 of the Paris metro.]]

The total length of the viaduct is 199 m. Made up of steel [[Beam (structure)|beams]] resting on concrete piers, the viaduct has a continuous gradient, due to the difference in level between the two [[Bank (geography)|banks]] of the Marne. It was renovated for the first time in 2011.

== Location ==
The viaduct is located between the [[Charenton–Écoles (Paris Métro)|Charenton-Écoles]] and [[Maisons-Alfort–Stade (Paris Métro)|Maisons-Alfort–Stade]] stations. It crosses the [[103 departmental road]], the [[A4 autoroute]] and then the [[Marne (department)|Marne]]. Since [[Charenton-le-Pont]] is located on a hillside overlooking the [[Marne (river)|Marne]], the viaduct is inclined to compensate for the difference in level between the two stations.<ref name=":0">"[http://transportparis.canalblog.com/pages/quand-le-metro-franchit-la-seine/33408149.html Quand le métro franchit la Seine]" [https://archive.wikiwix.com/cache/?url=http%3A%2F%2Ftransportparis.canalblog.com%2Fpages%2Fquand-le-metro-franchit-la-seine%2F33408149.html archive], on ''transportparis.canalblog.fr'' (accessed 28 October 2020).</ref> The structure is flanked by two [[Tramway track|tramways]], enabling [[Paris Métro Line 8|line 8]] to return underground.<ref name=":1">[[:fr:Viaduc-métro de Charenton#Robert1983|Robert 1983]], <abbr>p.</abbr> 216.</ref>

The surrounding bridges are the [[Pont de Charenton|Charenton bridge]], to the east, and the railway viaduct of the [[Paris–Marseille railway]], to the west.<ref>[[:fr:Viaduc-métro de Charenton#Lamming2015|Lamming 2015]], <abbr>p.</abbr> 280.</ref> The structure is only a few hundred meters away from the confluence of the [[Marne (river)|Marne]] and [[Seine]] rivers.

== Technical specifications ==
[[File:Coupe viaduc charenton.jpg|left|thumb|207x207px|Longitudinal section of the structure.]]
The total length of the viaduct is 199 m, with an average height of 15.05 m between the rail and the water level. The structure has a continuous gradient of 41&nbsp;mm/m towards [[Maisons-Alfort]]. It comprises two 55.5 m central [[Travée|sections]] and two 30 m lateral sections. The structure rests on six supports for three concrete [[Pile (bridge)|piles]], one of which is set in the riverbed.<ref name=":1" />

The steel [[Deck (bridge)|deck]] is designed to aesthetically blend into the landscape. It consists of a continuous beam supported by two vertical solid-core girders located between the two tracks. By enclosing the lower part of the trains, they minimize rolling noise. The track rests on [[ballast]], which is laid on a concrete [[screed]].<ref name=":1" />

== History ==
{{Category more|Paris Métro Line 8}}
With the [[Charenton bridge]] becoming too saturated, in 1965 it was decided to extend [[Paris Métro Line 8|line 8]] from [[Charenton–Écoles (Paris Métro)|''Charenton-Écoles'']] to [[Maisons-Alfort]] and [[Créteil]].<ref>[[:fr:Viaduc-métro de Charenton#Robert1983|Robert 1983]], <abbr>p.</abbr> 162.</ref> To achieve this, the line had to cross the [[Marne (river)|Marne]], but the difference in level between the two banks was too great to allow the line to pass under the river, as [[Charenton-le-Pont|Charenton]] was located on a highland plateau. Instead, an elevated viaduct crossing was chosen – a first for a [[Paris Métro|Paris metro]] since 1909.<ref>[[:fr:Viaduc-métro de Charenton#Robert1983|Robert 1983]], <abbr>p.</abbr> 163.</ref>

This extension, which had been planned as early as the 1930s, had been postponed due to [[World War II]]. In anticipation of the metro's construction, buildings in [[Charenton's Rue de Paris]] were expropriated in 1937, including the [[Hôtel du Plessis-Bellière]].<ref>"[http://www2.culture.gouv.fr/public/mistral/merimee_fr?ACTION=CHERCHER&FIELD_1=REF&VALUE_1=IA00060672 Hôtel dit hôtel du Plessis Bellière, puis Chamillart]" [https://archive.wikiwix.com/cache/?url=http%3A%2F%2Fwww2.culture.gouv.fr%2Fpublic%2Fmistral%2Fmerimee_fr%3FACTION%3DCHERCHER%26FIELD_1%3DREF%26VALUE_1%3DIA00060672 archive], notice no. IA00060672, Mérimée database, French Ministry of Culture</ref> The upper part of Square Jules Noël and Place de Valois, as well as the buildings lining it, were built to replace the destroyed buildings.<ref>Marie-François Laborde, ''Charenton-le-Pont A story in three parts'', Charenton, Maury imprimeur, 2008 ({{ISBN|978-2-9532292-0-2}}), <abbr>p.</abbr> 46</ref>
[[File:Rame Métro Pont ferroviaire Ligne 8 Métro Paris Charenton Pont 1.jpg|left|thumb|263x263px|An [[MF 77]] crosses the viaduct on its way to Paris.]]
Construction of the viaduct began in the spring of 1968, with the construction of the piers. The steel girders were installed in June 1969, and the viaduct was completed in November, enabling load tests to be carried out using five-motor [[Sprague-Thomson]] trains.<ref name=":1" /> The line was opened to traffic on 19 September 1970, with the extension of line 8 from [[Charenton–Écoles (Paris Métro)|''Charenton-Écoles'']] to [[Maisons-Alfort–Stade (Paris Métro)|''Maisons-Alfort-Stade'']].<ref name=":0" />

In the context of the extension of line 8 to ''[[Pointe du Lac (Paris Métro)|Pointe du Lac]]'', the viaduct was closed for renovations during the summers of 2010 and 2011, with a replacement shuttle service in place during this period. The aim of the renovation is to improve the soundproofing of the structure and adapt it to the increased traffic associated with the extension.<ref>"[https://www.leparisien.fr/val-de-marne-94/charenton-le-pont-94220/le-viaduc-est-renove-le-metro-repart-05-09-2011-1592659.php Le viaduc est rénové, le métro repart]" [https://archive.wikiwix.com/cache/?url=https%3A%2F%2Fwww.leparisien.fr%2Fval-de-marne-94%2Fcharenton-le-pont-94220%2Fle-viaduc-est-renove-le-metro-repart-05-09-2011-1592659.php archive], on ''leparisien.fr'', 5 September 2011 (accessed 28 October 2020).</ref> After the removal of the tracks and [[ballast]], the concrete slab was replaced and then covered with an anti-vibration [[Natural rubber|rubber]] coating, reducing noise levels by 10&nbsp;dB per train. At the same time, the viaduct was repainted in a blue-green color, replacing the original blue-gray. The total cost of the project was four million euros.<ref>Hervé Guénot, "[https://www.lemoniteur.fr/article/refection-du-viaduc-en-vue-de-l-extension-de-la-ligne-8.1104419 Réfection du viaduc en vue de l'extension de la ligne 8]" [https://archive.wikiwix.com/cache/?url=https%3A%2F%2Fwww.lemoniteur.fr%2Farticle%2Frefection-du-viaduc-en-vue-de-l-extension-de-la-ligne-8.1104419 archive], on ''lemoniteur.fr'', 6 August 2010 (accessed 28 October 2020).</ref>

== References ==
<references />

== See also ==

=== Bibliography ===

* Jean Robert, ''Notre Métro'', Paris, éd. Jean Robert, 1983, <abbr>2<sup>e</sup></abbr> <abbr>éd.</abbr>, 511 <abbr>p.</abbr> 
* Clive Lamming, ''La grande histoire du métro parisien de 1900 à nos jours'', Atlas, October 2015, 336 <abbr>p.</abbr> {{ISBN|978-2-344-00403-6}}

=== Related articles ===

* [[Paris Métro Line 8]]
* [[Bridge|Pont ferroviaire]]
* [[Crueize Viaduct]]

=== External links ===
Architectural resource: [http://fr.structurae.de/structures/data/index.cfm?ID=20013164 Structurae]

{{List of bridges in France}}

[[Category:Trains]]
[[Category:Paris Métro]]
[[Category:Viaducts in France]]
[[Category:Île-de-France]]
[[Category:Engineering]]