View source for Arch bridge

{{short description|Bridge with arch-shaped supports}}
{{About
|the structure type|specific bridges with this name|Arch Bridge (disambiguation)}}
<!--Note that this taxobox is for generic bridge types, not specific (except as an example).
The ancestor, sibling, and descendent references should follow the current taxonomy at media:BridgeTaxonomy.jpg,
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{{BridgeTypePix
|image=NagasakiMeganebashi.jpg
|image_title=[[Megane Bridge|A double-arch stone bridge]] in [[Nagasaki]], Japan
|type_name=Arch bridge
|sibling_names=
|descendent_names=[[Truss arch bridge]], [[moon bridge]] (masonry)
|ancestor_names=[[Clapper bridge]]
|carries=[[Pedestrian]]s, [[vehicle]]s, [[light rail]], [[heavy rail]], water
|span_range=short, but often set end-to-end to form a large total length
|material=[[masonry]], [[concrete]], [[wrought iron]], [[cast iron]], [[timber]], [[structural steel]]
|movable=No
|design=Low
|falsework=Yes}}
An '''arch bridge''' is a bridge with [[abutment]]s at each end shaped as a curved [[arch]]. Arch bridges work by transferring the weight of the bridge and its [[structural load|loads]] partially into a horizontal thrust restrained by the abutments at either side, and partially into a vertical load on the arch supports. A [[viaduct]] (a long bridge) may be made from a series of arches, although other more economical structures are typically used today.
== History ==
{{See also|List of Roman bridges|List of medieval stone bridges in Germany|List of medieval bridges in France}}
[[File:Bridge Alcantara.JPG|thumb|left|The Roman [[Alcántara Bridge]], Spain (built 103-106 AD)]]
[[File:Anji (Zhaozhou) Bridge 2011.jpg|thumb|The [[Anji Bridge]], 6–7th century AD]]
Possibly the oldest existing arch bridge is the [[Mycenaean Greece|Mycenaean]] [[Arkadiko Bridge]] in Greece from about 1300 BC. The stone [[corbel arch]] bridge is still used by the local populace.<ref>[http://odysseus.culture.gr/h/2/eh251.jsp?obj_id=1710 Hellenic Ministry of Culture: Mycenaean bridge at Kazarma] {{webarchive |url=https://web.archive.org/web/20080408153052/http://odysseus.culture.gr/h/2/eh251.jsp?obj_id=1710 |date=8 April 2008 }}</ref> The well-preserved [[Hellenistic]] [[Eleutherna Bridge]] has a triangular corbel arch.<ref>Nakassis, Athanassios (2000): "The Bridges of Ancient Eleutherna", ''The Annual of the British School at Athens'', Vol. 95, pp. 353–365</ref> The 4th century BC [[Rhodes Footbridge]] rests on an early [[voussoir]] arch.<ref>{{harvnb|Galliazzo|1995|p=36}}; {{harvnb|Boyd|1978|p=91}}</ref>
Although [[true arch]]es were already known by the [[Etruscans]] and [[ancient Greeks]], the [[Ancient Rome|Romans]] were &ndash; as with the [[Vault (architecture)|vault]] and the [[dome]] &ndash; the first to fully realize the potential of arches for bridge construction.<ref>Robertson, D.S.: Greek and Roman Architecture, 2nd edn., Cambridge 1943, p. 231: <blockquote>"The Romans were the first builders in Europe, perhaps the first in the world, fully to appreciate the advantages of the arch, the vault and the dome."</blockquote></ref> A list of [[Roman bridge]]s compiled by the engineer Colin O'Connor features 330 [[List of Roman bridges#Masonry bridges|Roman stone bridges]] for traffic, 34 [[List of Roman bridges#Timber and stone pillar bridges|Roman timber bridges]] and 54 [[List of Roman bridges#Aqueduct bridges|Roman aqueduct bridges]], a substantial part still standing and even used to carry vehicles.<ref>O'Connor, Colin: "Roman Bridges", Cambridge University Press 1993, p. 187ff. {{ISBN|0-521-39326-4}}</ref> A more complete survey by the Italian scholar Vittorio Galliazzo found 931 Roman bridges, mostly of stone, in as many as 26 countries (including former [[Yugoslavia]]).<ref>Galliazzo, Vittorio (1994), I ponti romani. Catalogo generale, Vol. 2, Treviso: Edizioni Canova, {{ISBN|88-85066-66-6}}, cf. Indice</ref>
Roman arch bridges were usually [[semicircular]], although a number were segmental arch bridges (such as [[Alconétar Bridge]]), a bridge which has a curved arch that is less than a semicircle.<ref>{{cite web|url=http://imgs.ebuild.com/woc/M880252.pdf |title=Designing the segmental arch |last=Beall |first=Christine |year=1988 |publisher=ebuild.com |access-date=8 May 2010 }}</ref> The advantages of the [[circular segment|segmental]] arch bridge were that it allowed great amounts of flood water to pass under it, which would prevent the bridge from being swept away during floods and the bridge itself could be more lightweight.<ref>Temple, Robert. The Genius of China: 3,000 Years of Science, Discovery, and Invention. New York: Touchstone, 1986.</ref> Generally, Roman bridges featured wedge-shaped primary arch stones ([[voussoir]]s) of the same in size and shape. The Romans built both single spans and lengthy multiple arch [[Roman aqueducts|aqueducts]], such as the [[Pont du Gard]] and [[Segovia Aqueduct]]. Their bridges featured from an early time onwards flood openings in the piers, e.g. in the [[Pons Fabricius]] in Rome (62 BC), one of the world's oldest major bridges still standing.
[[File:AcueductoSegovia edit1.jpg|thumb|[[Segovia Aqueduct]] ({{circa|100 AD}})]]
Roman engineers were the first and until the [[Industrial Revolution]] the only ones to construct bridges with [[Roman concrete|concrete]], which they called [[Opus caementicium]]. The outside was usually covered with brick or [[ashlar]], as in the [[Alcántara Bridge]].
The Romans also introduced segmental arch bridges into bridge construction. The {{Convert|330|m||-long|abbr=on|adj=mid}} [[Limyra Bridge]] in southwestern [[Turkey]] features 26 segmental arches with an average span-to-rise ratio of 5.3:1,<ref>O'Connor, Colin: "Roman Bridges", Cambridge University Press 1993, p. 126 {{ISBN|0-521-39326-4}}</ref> giving the bridge an unusually flat profile unsurpassed for more than a millennium. [[Trajan's bridge]] over the [[Danube]] featured open-[[spandrel]] segmental arches made of wood (standing on {{Convert|40|m||-high|abbr=on|adj=mid}} concrete piers). This was to be the longest arch bridge for a thousand years both in terms of overall and individual span length, while the longest extant Roman bridge is the {{Convert|790|m||-long|abbr=on|adj=mid}} long [[Puente Romano]] at [[Mérida, Spain|Mérida]]. The late Roman [[Karamagara Bridge]] in [[Cappadocia]] may represent the earliest surviving bridge featuring a pointed arch.<ref>{{harvnb|Galliazzo|1995|pp=92, 93 (fig. 39)}}</ref>
[[File:Pont du Diable - Céret.JPG|thumb|left|[[Pont du Diable (Céret)|Devil's bridge]], [[Céret]], France (1341)]]
In [[medieval]] Europe, bridge builders improved on the Roman structures by using narrower [[pier (architecture)|piers]], thinner arch barrels and higher span-to-rise ratios on bridges. [[Gothic architecture|Gothic]] pointed arches were also introduced, reducing lateral thrust, and spans increased as with the eccentric [[Puente del Diablo (Martorell)|Puente del Diablo]] (1282).
The 14th century in particular saw bridge building reaching new heights. Span lengths of {{Convert|40|m||abbr=on}}, previously unheard of in the history of masonry arch construction, were now reached in places as diverse as Spain ([[Puente de San Martín]]), Italy ([[Castelvecchio Bridge]]) and France ([[Pont du Diable (Céret)|Devil's bridge]] and [[Pont Grand (Tournon-sur-Rhône)|Pont Grand]]) and with arch types as different as semi-circular, pointed and segmental arches. The [[Trezzo sull'Adda Bridge|bridge at Trezzo sull'Adda]], destroyed in the 15th century, even featured a span length of {{Convert|72|m||abbr=on}}, not matched until 1796.<ref>Troyano, Leonardo Fernández: Bridge Engineering. A Global Perspective, Thomas Telford Publishing, London 2003, {{ISBN|0-7277-3215-3}}, p. 49</ref>
[[File:Firenze.Ponte Vecchio01.jpg|thumb|The [[Ponte Vecchio]], [[Florence]], Italy (1345)]]
Constructions such as the acclaimed [[Florence|Florentine]] segmental arch bridge [[Ponte Vecchio]] (1345) combined sound engineering (span-to-rise ratio of over 5.3 to 1) with aesthetical appeal. The three elegant arches of the [[Renaissance]] [[Ponte Santa Trinita]] (1569) constitute the oldest elliptic arch bridge worldwide. Such low rising structures required massive [[abutment]]s, which at the [[Venice|Venetian]] [[Rialto bridge]] and the [[Fleischbrücke]] in [[Nuremberg]] (span-to-rise ratio 6.4:1) were founded on thousands of wooden piles, partly rammed obliquely into the grounds to counteract more effectively the lateral thrust.
[[File:Richmond Bridge Panorama Restitch.jpg|thumb|left|[[Richmond Bridge (Tasmania)|Richmond Bridge]], oldest operational bridge in Australia (1825)]]
In China, the oldest existing arch bridge is the [[Zhaozhou Bridge]] of 605 AD, which combined a very low span-to-rise ratio of 5.2:1, with the use of spandrel arches (buttressed with iron brackets). The Zhaozhou Bridge, with a length of {{convert|167|ft|m}} and span of {{convert|123|ft|m}}, is the world's first wholly stone open-spandrel segmental arch bridge, allowing a greater passage for flood waters.<ref name="Needham">Needham, Joseph. ''The Shorter Science and Civilisation in China''. Cambridge University Press, 1994. {{ISBN|0-521-29286-7}}. pp. 145–147.</ref> Bridges with perforated spandrels can be found worldwide, such as in China ([[Zhaozhou Bridge]], 7th century). Greece ([[Bridge of Arta]], 17th century) and Wales ([[Cenarth Bridge]], 18th century).
[[File:Ironbridge 6.jpg|thumb|[[The Iron Bridge]], opened in 1781, is an early example of a large cast iron bridge.]]
In more modern times, stone and brick arches continued to be built by many civil engineers, including [[Thomas Telford]], [[Isambard Kingdom Brunel]] and [[John Rennie (father)|John Rennie]]. A key pioneer was [[Jean-Rodolphe Perronet]], who used much narrower piers, revised calculation methods and exceptionally low span-to-rise ratios. Different materials, such as [[cast iron]], [[steel]] and [[concrete]] have been increasingly used in the construction of arch bridges.
== Simple compression arch bridges ==
=== Advantages of simple materials ===
[[File:MonroeStreetBridgea.jpg|thumb|550px|Falsework [[centering]] in the center arch of [[Monroe Street Bridge (Spokane River)|Monroe Street Bridge]], [[Spokane, Washington]]. 1911.]]
[[File:Vanha kivisilta DSC08273 C.JPG|thumb|The old stone arch bridge over the [[Kerava River]] in [[Kerava]], [[Finland]]]]
Stone, brick and other such materials are strong in [[compression (physical)|compression]] and somewhat so in [[shearing (physics)|shear]], but cannot resist much force in [[tension (mechanics)|tension]]. As a result, masonry arch bridges are designed to be constantly under compression, so far as is possible. Each arch is constructed over a temporary [[falsework]] frame, known as a [[centring]]. In the first compression arch bridges, a [[Keystone (architecture)|keystone]] in the middle of the bridge bore the weight of the rest of the bridge. The more weight that was put onto the bridge, the stronger its structure became. Masonry arch bridges use a quantity of fill material (typically compacted rubble) above the arch in order to increase this dead-weight on the bridge and prevent tension from occurring in the arch ring as loads move across the bridge. Other materials that were used to build this type of bridge were brick and unreinforced concrete. When masonry (cut stone) is used the angles of the faces are cut to minimize shear forces. Where random masonry (uncut and unprepared stones) is used they are mortared together and the mortar is allowed to set before the falsework is removed.
Traditional masonry arches are generally durable, and somewhat resistant to [[settlement (construction)|settlement]] or undermining. However, relative to modern alternatives, such bridges are very heavy, requiring extensive [[foundation (architecture)|foundations]]. They are also expensive to build wherever labor costs are high.
===Construction sequence===
[[File:Limyra Bridge Workflow.gif|thumb|300px|Workflow on the Roman [[Limyra Bridge|Bridge at Limyra]]: the falsework was moved to another opening as soon as the lower arch rib had been completed]]
* Where the arches are founded in a watercourse bed (on piers or banks) the water is diverted so the gravel can first be excavated and replaced with a good footing (of strong material). From these, the foundation [[pier (architecture)|piers]] are erected/raised to the height of the intended base of the arches, a point known as the '''springing'''.
* Falsework [[centering]] (in British English: arch frame) is fabricated, typically from timbers and boards. Since each arch of a multi-arch bridge will impose a thrust upon its neighbors, it is necessary either that all arches of the bridge be raised at the same time, or that very wide piers be used. The thrust from the end arches is taken into the earth by substantial (vertical) footings at the canyon walls, or by large inclined planes forming in a sense ramps to the bridge, which may also be formed of arches.
* The several arches are (or single arch is) constructed over the centering. Once each basic '''arch barrel''' is constructed, the arches are (or arch is) stabilized with infill masonry above, which may be laid in horizontal [[running bond]] courses (layers). These may form two outer walls, known as the '''spandrels''', which are then infilled with appropriate loose material and rubble.
* The road is paved and [[parapet]] walls protectively confine traffic to the bridge.
== 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 and canal viaducts ===
<gallery mode="packed" caption="Aqueducts and canal viaducts">
File:Pont romain-Pont st Martin.jpg|Roman [[Pont-Saint-Martin (bridge)|Pont-Saint-Martin]]
File:Pont du Gard BLS.jpg|The three-story Roman [[Pont du Gard]] [[Aqueduct (watercourse)|aqueduct]]
File:Limyra Bridge Arch.svg|The Roman segmental arch [[Bridge at Limyra]]
</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:arch bridge nomenclature.png|Diagram of an open-spandrel deck arch bridge
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 ===
{{multiple image
| direction = horizontal
| footer = Springing point hinge (left) and crown hinge (right) on a three-hinged arch bridge in Namur, Belgium
| image1 =Namur three-hinged arch bridge 02.JPG
| image2 = Namur three-hinged arch bridge 01.JPG
| total_width = 400px
}}
{{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>
==Gallery==
{{Cleanup gallery|date=July 2021}} <!-- Does it really matter? -->
<gallery mode="packed" caption="Different types of arch bridges">
File:Stari Most22.jpg|Single-arch bridge [[Stari most]] in [[Mostar]] in [[Bosnia and Herzegovina]]
File:Puente del Diablo, Martorell, Catalonia, Spain. Pic 01.jpg|Pointed arch of the [[Puente del Diablo (Martorell)|Puente del Diablo]] in Spain
File:Alte Nahebrücke, Bad Kreuznach.jpg|[[Alte Nahebrücke (Bad Kreuznach)|Alte Nahebrücke]] ({{circa|1300}}) supports buildings on its piers
File:J24 089e Krämerbrücke.jpg|[[Krämerbrücke]] (1325) – longest continuously inhabited bridge in Europe.
File:Ponte Santa Trinita a Firenze.jpg|[[Ponte Santa Trinita]]. First bridge with elliptic arches
File:Rialto bridge 2011.jpg|[[Rialto Bridge]] over the [[Grand Canal (Venice)|Grand Canal]] in [[Venice]], Italy (2011)
File:Gaoliang Bridge.JPG|A masonry [[moon bridge]] showing the buttressing approach ramps that take the horizontal thrust of the arch
File:Fredrikstad BridgeacrossGlomma01.JPG|Fredrikstad bridge in [[Fredrikstad]], [[Norway]]
File:MainStPano.jpg|The [[Main Street Bridge (Columbus)|Main Street Bridge]] in [[Columbus, OH]] is the only inclined-arch suspension bridge in North America.
File:Chaotianmen Yangtze River Bridge.JPG|The [[Chaotianmen Bridge]] in [[Chongqing]], [[China]], is the world's longest [[through arch bridge]].
File:Το Γεφύρι της Άρτας.JPG|[[Bridge of Arta]] in [[Arta, Greece]]
File:Garabit.jpg|The [[Garabit Viaduct]] is a wrought iron [[truss arch bridge]].
File:Velia.jpg|The [[dry stone]] bridge, so called ''Porta Rosa'' (4th century BC), in [[Velia (town)|Elea]], [[Province of Salerno]], [[Campania]], Italy (2005)
File:Krumlov13(js).jpg|Bridge in [[Český Krumlov]], Czech Republic (2004)
File:Grosvenor Bridge Chester3.JPG|[[Grosvenor Bridge (Chester)|Grosvenor Bridge]] over the [[River Dee, Wales|River Dee]] in [[Chester]], [[Cheshire]], [[England]], U.K. (2007)
File:Union Arch Bridge MD 2008.jpg|[[Union Arch Bridge]] carrying the [[Washington Aqueduct]] and [[MacArthur Boulevard (Washington, D.C.)|MacArthur Boulevard]] (formerly named Conduit Road), [[Cabin John, Maryland|Cabin John]], [[Montgomery County, Maryland|Montgomery County]], [[Maryland]], U.S.A. (2008)
File:Memorial Bridge sunrise.jpg|[[Arlington Memorial Bridge]] over the [[Potomac River]] in [[Washington, D.C.]], U.S.A. (2007)
File:Key Bridge, Washington D.C.jpg|[[Francis Scott Key Bridge (Washington)|Francis Scott Key Bridge]] over the [[Potomac River]] in [[Washington, D.C.]], U.S.A. (2006)
File:2007 04 25 - WWB 44.JPG|[[Woodrow Wilson Bridge]] carrying [[Interstate 95]] (I-95) and the [[Capital Beltway]] over the [[Potomac River]] between [[Alexandria, Virginia]] and [[Oxon Hill, Maryland]], U.S.A. (2007)
File:Tyne Bridge - Newcastle Upon Tyne - England - 2004-08-14.jpg|[[Tyne Bridge]] over the [[River Tyne]], [[Newcastle upon Tyne]], [[England]], U.K. (2004)
File:Hell Gate Bridge by Dave Frieder.jpg|[[Hell Gate Bridge]] over the [[East River]], [[New York City]], [[New York (state)|New York]], U.S.A.
File:Sydney Harbour Bridge from Circular Quay.jpg|[[Sydney Harbour Bridge]], [[Sydney]], [[New South Wales]], Australia (2010)
File:201701 G164 on Jinhua–Wenzhou HSR over Daxi River.jpg|Daxi River Bridge of [[Jinhua–Wenzhou High Speed Railway]]
</gallery>
== Use of modern materials ==
Most modern arch bridges are made from [[reinforced concrete]]. This type of bridge is suitable where a temporary centring may be erected to support the forms, reinforcing steel, and uncured concrete. When the concrete is sufficiently set the forms and falseworks are then removed. It is also possible to construct a reinforced concrete arch from [[precast concrete]], where the arch is built in two halves which are then leaned against each other.
Many modern bridges, made of steel or reinforced concrete, often bear some of their load by tension within their structure. This reduces or eliminates the horizontal thrust against the abutments and allows their construction on weaker ground. Structurally and analytically they are not [[true arch]]es but rather a [[beam (structure)|beam]] with the shape of an arch. See [[truss arch bridge]] for more on this type.
A modern evolution of the arch bridge is the long-span [[through arch bridge]]. This has been made possible by the use of light materials that are strong in tension such as steel and prestressed concrete.
== See also ==
{{div col}}
* [[Deck (bridge)]]
* [[List of arch bridges by length]]
* [[List of longest masonry arch bridge spans]]
* [[Natural arch]]
* [[Parabolic arch]]
* [[Roman bridge]]
* [[Skew arch]]
* [[Through arch bridge]]
* [[Tied arch bridge]]
* [[Truss arch bridge]]
{{div col end}}
== Footnotes ==
{{Reflist}}
== References ==
* {{Citation
| last = Boyd
| first = Thomas D.
| title = The Arch and the Vault in Greek Architecture
| journal = [[American Journal of Archaeology]]
| volume = 82
| issue = 1
| year = 1978
| pages = 83–100 (91)
| doi = 10.2307/503797
| jstor = 503797
| s2cid = 194040597
}}
* {{Citation
| last = Galliazzo
| first = Vittorio
| title = I ponti romani
| volume = 1
| year = 1995
| publisher = Edizioni Canova
| location = Treviso
| isbn = 88-85066-66-6
}}
* {{Citation
| last = Galliazzo
| first = Vittorio
| title = I ponti romani. Catalogo generale
| volume = 2
| year = 1994
| publisher = Edizioni Canova
| location = Treviso
| isbn = 88-85066-66-6
}}
* {{Citation
| last = O’Connor
| first = Colin
| title = Roman Bridges
| publisher = Cambridge University Press
| year = 1993
| page = 129
| isbn = 0-521-39326-4
}}
* {{Citation
| last = Proske
| first = Dirk
| title = Safety of historical stone arch bridges
| publisher = Springer
| year = 2009
| page = 336
| isbn = 978-3-540-77616-1
}}
== External links ==
{{Commons category|Arch bridges}}
* [https://www.pbs.org/wgbh/nova/bridge/meetarch.html NOVA Online – Super Bridge – Arch Bridges]
* [https://web.archive.org/web/20050302094119/http://www.matsuo-bridge.co.jp/english/bridges/basics/arch.shtm Matsuo Bridge Co. – Arch Bridges]
* [http://bridges.midwestplaces.com/ Historic Bridges of the Midwest]
* [https://web.archive.org/web/20110711164818/http://hidden-hills.com/thearches/ Historic Arch Railroad Bridges in Western Massachusetts]
{{Bridge footer}}
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{{DEFAULTSORT:Arch Bridge}}
[[Category:Arch bridges| ]]
[[Category:Bridges by structural type]]