Editing Arch bridge (section)

== Types of arch bridge ==
=== Corbel arch bridge ===
{{See also|Corbel arch}}
<gallery mode="packed">
File:arkadiko2.jpg|Corbel arch built from [[Cyclopean masonry]], in the Greek [[Arkadiko bridge]]
File:Eleutherna Bridge, Crete, Greece. Pic 03.jpg|Corbel arch in the shape of an [[isosceles triangle]], supporting the Greek [[Eleutherna Bridge]]
File:Corbelledarch.png|A corbelled arch with the masonry untrimmed
File:Trabeate Arch in New Delhi India.jpg|A corbel arch with the masonry cut into an arch shape
</gallery>
The corbel arch bridge is a masonry, or stone, bridge where each successively higher course (layer) cantilevers slightly more than the previous course.<ref>{{Citation| last =Richman| first =Steven M.| url=https://books.google.com/books?id=vt6g4eRkCDgC| year =2005| title =The Bridges of New Jersey| publisher =Rutgers University Press| page =23| isbn =978-0-8135-3510-4}}</ref> The steps of the masonry may be trimmed to make the arch have a rounded shape.<ref>{{Citation| last =Harris| first =Cyril M.| url=https://books.google.com/books?id=6n4JLmyooTwC| year =1983| title =Illustrated Dictionary of Historic Architecture| publisher =Courier Dover Publications| page =137| isbn =978-0-486-24444-0}}</ref> The [[corbel arch]] does not produce thrust, or outward pressure at the bottom of the arch, and is not considered a [[true arch]]. It is more stable than a [[true arch]] because it does not have this thrust. The disadvantage is that this type of arch is not suitable for large spans.<ref>{{Citation| last =Simpson| first =Frederick Moore| url=https://books.google.com/books?id=_FQpAAAAYAAJ| year =1913| title =A history of architectural development| publisher =Longmans, Green, and Co.| page =25}}</ref>

===Aqueducts===
<gallery mode="packed" caption="[[Aqueduct (bridge)|Aqueducts]] — bridges carrying water-supply and [[navigable aqueduct]]s">
File:Pont du Gard BLS.jpg|The three-story Roman [[Pont du Gard]] [[Aqueduct (watercourse)|aqueduct]] near [[Nimes]], [[France]]
File:Aqueduct of Segovia 02.jpg|Roman [[Aqueduct of Segovia]], Spain
File:Tomar December 2008-4.jpg|The Aqueduto dos Pegões in [[Tomar]], [[Portugal]]
File:Vila do Conde 3.jpg|The Aqueduct of [[Vila do Conde]], Portugal with an distinct angular turn
File:Aquadukt, Kavala.jpg|16th-century Ottoman [[Kavala aqueduct]], [[Greece]] with both an distinct angular turn and a curve in the structure shown in an overhead image
File:1, Μεσαιωνικό υδραγωγείο Καμάρες Καβάλας (photosiotas).jpg|Kavala aqueduct near Nikotsara Square showing the curve of the structure from street level
File:Acueducto, Arcos del Sitio, Tepotzotlán.jpg|The colonial Aqueduct, [[Tepotzotlán]], [[State of Mexico]]
File:Vanvitelli aqueduct.jpg|right|[[UNESCO]] [[World Heritage Site]] [[Aqueduct of Vanvitelli]], [[Italy]], built by [[Luigi Vanvitelli]] 
<br />
File:pontcysyllte aqueduct arp.jpg|UNESCO World Heritage Site [[Pontcysyllte Aqueduct]] carrying the [[Llangollen Canal]] by civil engineers [[Thomas Telford]] and [[William Jessop]] in [[Wales]], with a [[narrowboat]] crossing 
File:WalesC0047.jpg|The Pontcysyllte Aqueduct over the River Dee viewed from the Vale of [[Llangollen]], with a [[narrowboat]] crossing
File:Union icicle.jpg|The [[Almond Aqueduct]] carrying the [[Edinburgh and Glasgow Union Canal]] over [[River Almond, Lothian|River Almond]] at [[Ratho]] with a frozen overflow channel during the [[Winter of 2009–10 in Great Britain and Ireland|big freeze of 2010]]
File:Avon Aqueduct - geograph.org.uk - 1691980.jpg|The [[Avon Aqueduct]] carrying the [[Edinburgh and Glasgow Union Canal]] over the [[River Avon, Falkirk|Avon]] near [[Linlithgow]]
File:Dowley Gap Aqueduct - geograph.org.uk - 353210.jpg|The Dowley Gap or the Seven Arches Aqueduct by the civil engineer [[James Brindley]] carrying the [[Leeds and Liverpool Canal]] over the [[River Aire]], [[Yorkshire]]
File:Dundas Aqueduct, from south-east.jpg|The [[Dundas Aqueduct]] in [[Bath Stone]] by the civil engineer [[John Rennie (father)|John Rennie]] carrying the [[Kennet and Avon Canal]] over the [[River Avon, Bristol|River Avon]] and the [[Wessex Main Line]] railway at [[Limpley Stoke]], near [[Bath, Somerset|Bath]], [[England]]
File:Engine Arm Aqueduct east.jpg|The [[Engine Arm Aqueduct]], by the civil engineer [[Thomas Telford]] and cast by [[Horseley Ironworks]], carrying the [[Engine Arm]], a [[Birmingham Canal Navigations]] feeder, over the [[BCN Main Line]]
File:Engine Arm Aqueduct west.jpg|The Engine Arm Aqueduct close-up image showing the arch from below
</gallery>

In some locations it is necessary to span a wide gap at a relatively high elevation, such as when a canal or water supply must span a valley. Rather than building extremely large arches, or very tall supporting columns (difficult using stone), a series of arched structures are built one atop another, with wider structures at the base. Roman [[Civil engineering|civil engineers]] developed the design and constructed highly refined structures using only simple materials, equipment, and mathematics. This type is still used in canal viaducts and roadways as it has a pleasing shape, particularly when spanning water, as the reflections of the arches form a visual impression of circles or ellipses.

{{Anchor|Open-spandrel deck arch bridge}}
{{Anchor|Closed-spandrel deck arch bridge}}

=== Deck arch bridge ===
<gallery mode="packed" caption="Deck arch bridges">
File:Limyra Bridge Arch.svg|Diagram of a Roman segmental arch of a stone deck arch bridge with a closed spandrel <br/> — [[Bridge at Limyra]]
File:arch bridge nomenclature.png|Diagram of an open-spandrel deck arch bridge
File:Pont romain-Pont st Martin.jpg|Roman [[Pont-Saint-Martin (bridge)|Pont-Saint-Martin]]
File:Grosvenor_Bridge_Chester4.JPG|[[Grosvenor Bridge (Chester)]], a closed-spandrel arch bridge
File:Alexander Hamilton Bridge from river jeh.jpg|[[Alexander Hamilton Bridge]], an open-spandrel arch bridge
File:Galena_Creek_Bridge_in_June_2012.jpg|[[Galena Creek Bridge]], a cathedral arch bridge
</gallery>

{{anchor|Open-spandrel deck arch bridge}}
This type of bridge comprises an arch where the deck is completely above the arch. The area between the arch and the deck is known as the [[spandrel]]. If the spandrel is solid, usually the case in a masonry or stone arch bridge, the bridge is called a ''closed-spandrel deck arch bridge''. If the deck is supported by a number of vertical columns rising from the arch, the bridge is known as an ''open-spandrel deck arch bridge''. The [[Alexander Hamilton Bridge]] is an example of an open-spandrel arch bridge. Finally, if the arch supports the deck only at the top of the arch, the bridge is called a [[cathedral arch|cathedral arch bridge]].<ref name="aspire2010w">{{cite web|url=http://www.aspirebridge.org/pdfs/magazine/issue_13/galena_creek_win10.pdf |title=Nevada's Galena Creek Bridge |last=Durski |first=Brad F. |date=Winter 2010 |access-date=18 June 2012 |work=Aspire |publisher=Precast/Prestressed Concrete Institute |url-status=dead |archive-url=https://web.archive.org/web/20100216230014/http://www.aspirebridge.org/pdfs/magazine/issue_13/galena_creek_win10.pdf |archive-date=16 February 2010 }}</ref>

:''{{Category see also|Deck arch bridges}}''
{{See also|Timeline of three longest supported deck arch bridge spans}}

=== Through arch bridge ===
{{Main|Through arch bridge}}
:''{{Category see also|Through arch bridges}}''
[[File:Cotter_Bridge_Spanning_White_River_closeup.jpg|right|thumb|[[Cotter Bridge]], a through arch bridge that has open spandrels]]
This type of bridge has an [[arch]] whose base is at or below the deck, but whose top rises above it, so the deck passes through the arch. The central part of the deck is supported by the arch via suspension cables or tie bars, as with a [[tied-arch bridge]]. The ends of the bridge may be supported from below, as with a deck arch bridge. Any part supported from arch below may have spandrels that are closed or open.

The [[Sydney Harbour Bridge]] and the [[Bayonne Bridge]] are a through arch bridge which uses a truss type arch.

=== Tied-arch bridge ===
{{Main|Tied-arch bridge}}

Also known as a bowstring arch, this type of arch bridge incorporates a tie between two opposite ends of the arch. The tie is usually the deck and is capable of withstanding the horizontal thrust forces which would normally be exerted on the abutments of an arch bridge.

The deck is suspended from the arch. The arch is in compression, in contrast to a suspension bridge where the [[catenary arch|catenary]] is in tension. A tied-arch bridge can also be a through arch bridge.

<gallery mode="packed">
File:USACE Fremont Bridge Portland.jpg|The deck of the [[Fremont Bridge (Portland)|Fremont Bridge]] goes [[Through arch bridge|through the arch]], the central span is suspended from and [[Tied arch bridge|ties the arch]], while the side spans of the deck are supported.
</gallery>

=== Hinged arch bridge ===
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{{Main|Hinged arch bridge}}
An arch bridge with hinges incorporated to allow movement between structural elements. A single-hinged bridge has a hinge at the [[Crown (arch)|crown of the arch]], a two-hinged bridge has hinges at both springing points and a three-hinged bridge has hinged in all three locations.<ref>{{cite book |last1=Reynolds |first1=Charles E. |last2=Steedman |first2=James C. |last3=Threlfall |first3=Anthony J. |title=Reinforced Concrete Designer's Handbook, Eleventh Edition |date=7 August 2007 |publisher=CRC Press |isbn=978-0-203-08775-6 |page=41 |url=https://books.google.com/books?id=hrOfsy89QxkC |language=en}}</ref>