Bridge
A
bridge is a structure built to
span a
gorge,
valley,
road,
railroad track,
river, body of
water, or any other physical obstacle. Designs may be built higher than otherwise needed in order to allow other traffic (particularly ship traffic) beneath.
The purpose of a bridge is to allow people travelling or cargo being transported easier passage by providing a more uniform, and more easily navigable route than what would otherwise be an uneven or impossible path.
The first bridges were spans made of wooden
logs or
planks and eventually
stones, using a simple support and crossbeam arrangement.
The
arch was first used by the
Roman Empire for bridges and
aqueducts, some of which still stand today. The Romans also had
cement, which reduced the variation of strength found in natural stone.
Brick and
mortar bridges were built after the Roman era, as the technology for cement was lost then later rediscovered.
Rope bridges, a simple type of suspension bridge, were used by the
Inca civilization in the
Andes mountains of
South America, just prior to European colonization in the
1500s.
During the
18th century there were many innovations in the
design of
timber bridges by
Hans Ulrich,
Johannes Grubenmann, and others. The first engineering book on building bridges was written by
Hubert Gautier in
1716.
With the rise of the
Industrial Revolution in the
19th century,
truss systems of
wrought iron were developed for larger bridges, but
iron did not have the
tensile strength to support large
loads. With the advent of
steel, which has a high tensile strength, much larger bridges were built, many using the ideas of
Gustave Eiffel.
The
Oxford English Dictionary traces the origin of the word
bridge to an
Old English word
brycg, of the same meaning, derived from a hypothetical
Proto-Germanic root
brugjō. There are
cognates in other
Germanic languages (for instance
Brücke in
German,
brug in
Dutch or
bro in
Danish and
Swedish).
The word for the Pope, pontiff, comes from the word (pontifex) for bridge builder.
There are four main types of bridges:
beam bridges,
cantilever bridges,
arch bridges and
suspension bridges.
By use
A bridge is usually designed for
trains,
pedestrian or
road traffic, a
pipeline or waterway for water transport or barge traffic. In some cases there may be restrictions in use. For example, it may be a bridge carrying a
highway and forbidden for
pedestrians and
bicycles, or a pedestrian bridge, possibly also for bicycles.
An
aqueduct is a bridge that carries water, resembling a
viaduct, which is a bridge that connects points of equal height.
Decorative and ceremonial bridges
To create a beautiful image, some bridges are built much taller than necessary. This type, often found in east-asian style gardens, is called a
Moon bridge, evoking a rising full moon.
Other garden bridges may cross only a dry bed of stream washed pebbles, intended only to convey an impression of a stream.
Often in palaces a bridge will be built over an artificial waterway as symbolic of a passage to an important place or state of mind. A set of five bridges cross a sinuous waterway in an important courtyard of the
Forbidden City in
Beijing,
China. The central bridge was reserved exclusively for the use of the Emperor, Empress, and their attendants.
Index to types of bridges
Image:Pont_du_gard.jpg|AqueductImage:NagasakiMeganebashi.jpg|Arch bridgeImage:PontBailey800px.jpg|Bailey bridgeImage:UniversityBridge-1Clip.jpg|Bascule bridgeImage:Small footbridge.jpg|Beam bridgeImage:no imagebowstring archImage:Concrete box girder bridge.JPG|Box girder bridgeImage:WWI bridge of boats Scheldt.jpg|Bridge of boatsImage:ThreeTwrBrCenter.jpg|Cable-stayed bridgeImage:ForthBridgeEdinburgh.jpg|Cantilever bridgeImage:Puente del Alamillo.jpg|Cantilever spar cable-stayed bridgeImage:Tarr steps clapper bridge.jpg|Clapper bridgeImage:Australia sydney-404.jpg|Compression arch suspended-deck bridgeImage:Guilford vermont covered bridge 20040820.jpg|Covered bridgeImage:CurlingBridgeClip.jpg|Curling bridgeImage:Fort ticonderoga drawbridge to demilune.jpg|DrawbridgeImage:NoImageYetRectFramed.png|Extradosed bridgeImage:EastbankEsplanade.jpg|Floating bridgeImage:Hoernbruecke.jpg|Folding bridgeImage:GirderBridge2.jpg|Girder bridgeImage:IRBSideViewClip.jpg|Inca rope bridgeImage:JetwayAtVancouverBC.jpg|JetwayImage:Guilford vermont bridge covered bridge interior 20040820.jpg|Lattice bridgeImage:BNSFBridgeClip.jpg|Lift bridgeImage:Vallorcine footpath bridge 2003-12-13.jpg|Log bridgeImage:16 Bay With Link 4.jpg|Medium Girder BridgeImage:SFTGMoonBridge.jpg|Moon bridgeImage:PlateGirderUnderTracks.jpg|Plate girder bridgeImage:ArmyPontoonBr.jpg|Pontoon bridgeImage:Uppsala Ultunabron02 2005-06-16.jpg|Retractable bridge
(Thrust bridge)Image:SegmentalBridgeFtLauderdale.jpg|Segmental bridgeImage:ProposedSFOBBEasternSpan.jpg|Self-anchored suspension bridgeImage:WinnepegBridge.jpg|Side-spar cable-stayed bridgeImage:StepStoneBridge.jpg|Step-stone bridgeImage:Holzbrücke bei Essing 1.jpg|Stressed ribbon bridgeImage:BridgeSubmerging4.jpg|Submersible bridgeImage:suspension.bridge.bristol.arp.750pix.jpg|Suspension bridgeImage:Railway swing bridge.jpg|Swing bridgeImage:FortPittBridge.jpg|Tied arch bridgeImage:Millenium_bridge_close.jpg|Tilt bridgeImage:Newport.transporter.750pix.jpg|Transporter bridgeImage:AlhambraTrestle.jpg|TrestleImage:Eastbound_over_SCB.jpg|Truss arch bridgeImage:LittleManateeRiver.jpg|Truss bridgeImage:Conwy Castle 2.jpg|Tubular bridgeImage:Toronto-bloorviaduct.jpg|ViaductImage:Grammene-vierendeelbridge 20030618.jpg|Vierendeel bridgeImage:Trogbrücke_Magdeburg.JPG|Water bridgeImage:WeighBridge5500.JPG|Weigh bridgeImage:BoxerwoodDotComZigZag.jpg|Zig-zag bridge
Index to bridge related topics
Image:BalsaBridge_Break.jpg|Balsa wood bridge under loadImage:Monet.waterlilies.500pix.jpg|Bridges in artImage:CaissonSchematic.jpg|CaissonImage:Paying Toll on passing a Bridge From a Painted Window in the Cathedral of Tournay Fifteenth Century.png|Toll bridge
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A bridge taxonomy showing evolutionary relationships |
Bridges may be classified by how the four forces of
tension,
compression,
bending and
shear are distributed through their structure. Most bridges will employ all of the principle forces to some degree, but only a few will predominate. The separation of forces may be quite clear. In a suspension or cable-stayed span, the elements in tension are distinct in shape and placement. In other cases the forces may be distributed among a large number of members, as in a truss, or not clearly discernible to a casual observer as in a box beam. Bridges can also be classified by their lineage, which is shown as the vertical axis on the diagram to the right.
A bridge's
structural efficiency may be considered to be the ratio of load carried to bridge weight, given a specific set of material types. In one common
challenge young students are to be divided into groups of two or three and then to be given a fixed quantity of wood sticks, a specific distance to span, and a given glue, and then to construct a bridge that will be tested to destruction by the progressive addition of load at the center of the span. The bridge taking the greatest load is by this test the most
structurally efficient. A more refined measure for this exercise is to weigh the completed bridge rather than measure against a fixed quantity of materials provided, a test that emphasizes economy of materials and efficient glue joints.
A bridge's
economic efficiency will be site and traffic dependent, the ratio of savings by having a bridge (instead of, for example, a ferry, or a longer road route) compared to its cost. For a given site, kind of bridge employed and the materials used determine the total cost, a lifetime cost composed of materials, labor, machinery, engineering, cost of money, maintenance, refurbishment, risk potential, and ultimately, demolition and associated disposal, recycling, and reuse. Bridges employing only compression are relatively inefficient structurally, but may be highly cost efficient where suitable materials are available near the site. For medium spans, trusses or box beams are usually most economical, while in some cases, the appearance of the bridge may be more important than its cost efficiency. The longest spans usually require suspension bridges.
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Akashi-Kaikyo Bridge -
Japan, with the longest section span of 1.9
km.
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Bosphorus Bridge -
Turkey, connects Asia and Europe
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Brooklyn Bridge - connecting the
New York City boroughs of
Manhattan and
Brooklyn.
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Charles Bridge -
Czech Republic, famous 14th century bridge in
Prague*
Confederation Bridge -
Canada, world's longest bridge over waters that freeze.
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Forth Railway Bridge -
Scotland, one of the most famous
cantilever bridges in the world.
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Golden Gate Bridge -
USA, one of the most famous
suspension bridges in the world.
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Great Belt Fixed Link, Eastern Bridge -
Denmark, second longest section span of 1.6
km*
Horai Bridge,
Shitzuoka, Japan. At 897.422 m (2,944 ft), the longest wooden toll bridge. Built in 1867.
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Hercilio Luz Bridge -
Florianopolis,
Brazil, longest brazilian
suspension bridge, one of the 100 largest
suspension bridges of the world and one of the oldest
hanging bridges in the world.
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The Iron Bridge -
England, the world's first
iron bridge.
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Jamuna Bridge-
Bangladesh, longest rail-road bridge in south asia , 2nd longest in world.
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Lake Pontchartrain Causeway -
USA, spanning
Lake Pontchartrain in south
Louisiana, it is the longest bridge in the world at 23.87
miles (38.41 km).
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Lupu Bridge-
China, longest single
steel arch.
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Mackinac Bridge -
USA, Opened to traffic in 1957, connecting the two
peninsulas of
Michigan; held the title of the world's longest two tower
suspension bridge between anchorages until the 1990s.
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Mahatma Gandhi Setu -
India, the longest river bridge in the world.
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Menai Suspension Bridge -
Wales, first road
suspension bridge in the world.
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Millau Viaduct -
France, the tallest vehicular bridge in the world.
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Øresundbroen/Öresundsbron -
Denmark -
Sweden*
Overtoun Bridge, -
Scotland,
dogs have leaped to their deaths from this bridge, leading to
urban legends.
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Palace Bridge -
St Petersburg,
Russia, one of iconic images of the city
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Penang Bridge -
Malaysia, longest bridge in
Southeast Asia.
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Québec Bridge -
Canada, largest
cantilever bridge in the world.
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San Francisco-Oakland Bay Bridge -
USA, especially for
seismic retrofit and
eastern span replacement.
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Sundial Bridge -
USA, a dramatic single cantilever spar cable stayed span for
pedestrians.
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Sunshine Skyway Bridge -
USA, longest cable-stayed concrete bridge in the world. Replaced a cantilever truss structure which partially collapsed in
1980 as a result of collision by a freighter.
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Sydney Harbour Bridge -
Australia, arguably the best-known suspended-deck compression arch bridge.
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Tacoma Narrows Bridge -
USA, famous for its collapse due to
aerodynamic effects.
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Tatara Bridge -
Japan, largest span cable-stayed bridge.
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Tower Bridge -
London,
England, and a symbol of this city.
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Tsing Ma Bridge -
Hong Kong, the world's longest rail & road suspension bridge
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Tyne Bridge -
England, one of
Northern England's most iconic structures.
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Trajan's bridge -
Romania,
ancient Roman bridge over the river
Danube, only fragments visible.
*U Bein Bridge in
Amarapura, a 1.2 km wooden footbridge, the longest teak bridge in the world.
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Vasco da Gama Bridge -
Portugal, the longest bridge in
Europe at 17.2 km.
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Verrazano-Narrows Bridge -
USA - longest suspension bridge in USA.
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Victoria Falls Bridge - linking
Zimbabwe to
Zambia, built in 1905 as part of the projected
Cape-Cairo railway.
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Zakim Bunker Hill Bridge -
USA, built during
Boston's
Big Dig, the widest
cable-stayed bridge.
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Pearl Harbor Memorial Bridge -
USA, will be the first
extradosed cable-stayed bridge constructed in the United States.
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Rio-Antirio bridge -
Greece, the longest
cable-stayed bridge in the world.
| Bridge | Town | Country | Date | Construction type, use of bridge | Reason | Number death/injuries | Damage! Remarks |
|---|
| Stirling Bridge | Stirling | Scotland | September 1297 | Beam and trestle over the River Forth | Overload by attackers during the Battle of Stirling Bridge | Unknown, attacking forces defeated | Bridge rendered unusable | Collapse may have been assisted by defending forces. |
| Bridge of Angers (France) | Angers | France | April 16th 1850 | Suspension bridge over Maine river | Resonance of soldiers led to collapse | 226/? | Bridge total damage | Marching columns now break step when crossing bridges. |
| Yarmouth Bridge | Great Yarmouth | England | May 2 1845 | Suspension | People had crowded onto the bridge to see a circus clown go down the river in a barrel pulled by geese. As the weight shifted as the barrel passed underneath the suspension chains on the south side snapped and the bridge deck tipped over. | 79 people drowned, mainly children. | Suspension chains snapped due to overload. | [1] |
| Tay Rail Bridge | Dundee | UK | December 28th 1879 | Continuous girder bridge, steel framework on cast iron columns, railway bridge | Insufficient consideration of the wind load, inadequate construction, collapsed because of the stresses caused by a storm | 75/0 | Bridge unusable, piers partly reused, train heavily damaged | Locomotive was saved from the Tay and was still in use 19 years later known as "The Diver". |
| Québec Bridge | Quebec | Canada | August 29th 1907 | Cantilever bridge, steel framework, railway bridge | Collapsed during construction | 74/11 | Bridge completely destroyed | |
| Theodor-Heuss-Rhine River Bridge | Ludwigshafen | Germany | March 1940 | Bridge of concrete, Motorway bridge | Collapsed during construction | ?/? | Bridge totally destroyed | Resulted in delay in completion of the motorway crossing of the Rhine until 1953 |
| Tacoma Narrows Bridge | USA | November 7th 1940 | Road bridge, cable suspension with plate girder deck | Aerodynamically poor form resulted in resonance | No | Bridge partially destroyed, one car lost, and one dog killed | Became known as "Galloping Gertie", in the first 4 months after opening up until its collapse under a previously unseen resonant mode. Since that time all new bridges have been modelled in wind tunnels. |
| The bridge at Remagen | Remagen | Germany | March 17th 1945 | Truss railroad and pedestrian bridge | Collapse due to previous battle damage incurred March 7th, 1945 | 28 U.S. soldiers | Total destruction | Capture of intact bridge offered significant short term tactical advangage to Allied forces. Collapse was not strategically significant due to placement of parallel floating bridges during the previous week |
| Harrow and Wealdstone rail crash | Harrow Weald | England | October 8th 1952 | Pedestrian footbridge | Collapse due to collision with train | 112 dead 340 injured | Total destruction | - | Tangiwai railway bridge | Tangiwai | New Zealand | December 24 1953 | Railway bridge | Damaged by lahar minutes before passenger train passed over it. | 134/151 | - | General Rafael Urdaneta Bridge | Maracaibo | Venezuela | April 6 1964 | Road bridge | Ship collision | 7 | 2 section collapsed | Currently in Operation |
| Silver Bridge | USA | 15 December 1967 | Road bridge, chain link suspension | Material fault and Corrosion | 46/9 | Bridge and 37 vehicles destroyed | |
| West Gate Bridge | Melbourne | Australia | October 15, 1970 | Road Bridge | Collapse during construction | 35 | 112 metre span between piers 10 and 11 collapsed | Section sprung back and collapse during attempts to remove a buckle cause by a difference in camber of 4.5 inches | |
| South Bridge Koblenz | Koblenz | Germany | 10 November 1971 | Road bridge | Bridge bent into Rhine | 13/? | Bridge completely destroyed | |
| Reichsbrücke | Vienna | Austria | August 1st, 1976 | Road bridge with Tram | Column fractured | 1/0 | Bridge, one bus and a lorry destroyed, ships damaged | Concrete of the column had never been examined, was internally totally destroyed; "higher force" |
| Almö Bridge | Stenungsund | Sweden | January 18, 1980 | Bridge with bow built of concrete | Ship collision | 8/? | Bridge and several cars destroyed | |
| Sunshine Skyway Bridge | | USA | 1980 | Steel Cantilever Bridge | Ship collision | 35/? | 1200 ft. of southbound span, several cars and a bus destroyed | Demolished and replaced with cable-stayed bridge |
| Aschaffenburg Main River Freeway Bridge | Aschaffenburg | Germany | 1988 | Bridge of Motorway A 3 over River Main | Error in construction | 1/0 | Bridge total damage | Partial collapse at Repetitive sliding |
| Bridge over railway line at Eschede | Eschede | Germany | June 3rd, 1998 | Road bridge | Train disaster | 101/105 | | Destruction by train crashing on pillar, killed and injured people were train passengers |
| Motorway bridge at Almuñecar, Province of Granada, Spain (search correct name of bridge) | Almuñecar | Spain | November 7th 2005 | Motorway bridge | Construction, accident, reason unknown | 6/3 | | A 60 metre long part fell 50 metre deep |
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BASE jumping*
Bridges in art*
List of bridges*
List of bridges by length*
List of largest suspension bridges*
Moveable bridge*
Pontoon bridge*
Toll bridge*
List of bridge disasters*
Balsa wood bridges*
Structurae - International Database and Gallery of Structures with over 10 000 Bridges.
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American Society of Civil Engineers History and Heritage of Civil Engineering - Bridges
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Bridge Building — Art and Science Comprehensive explanations about bridges.
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Bridge Basics A guide to bridge terminology and styles
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Bridge disasters*
A dictionary of bridge terms*
Digital Bridge Library at Lehigh University*
Flickr Pictures tagged with Bridge by most interesting*
Bridges and Tunnels of Allegheny County and Pittsburgh, PA Details of over 2,000 bridges of 8 feet span or greater. Bridge engineers hold their conventions in Pittsburgh.
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Federal Highway Administration Bridge Technology*
RRbridge (Yahoo Groups)
