Civil Engineering Mega Structures Bridge Definition:A bridge is structure which allows passage over an obstruction. The obstructions may be river, valley, rail route or road way etc. Bridge is a structure built to span physical obstacles without closing the way underneath such as a body of water, water, valley valley,, or road road,, for the purpose of providing passage over the obstacle, usually something so mething that can be detrimental to cross otherwise. There are many different designs that each serve a particular purpose and apply to different situations. Designs of bridges vary depending on the function of the bridge, the nature of the terrain where the bridge is constructed and anchored, the material used to make it, and the funds available to build it.
Types of Bridges:Bridges are classified into so many types based on different criteria’s. They
are explained below.
Arch Bridge
Truss Bridge
Suspension Bridge
Cable Stayed Bridge
Moveable Bridge
Pedestrian Bridge
Train Bridge
Pipeline Bridge
Glass Bridge
Under Sea Bridge
Arch Bridge:An arch bridge is a bridge with abutments at each end shaped as a curved arch. Arch bridges work by transferring the weight of the bridge and its loads partially into a horizontal thrust restrained by the abutments at either side. A viaduct (a long bridge) may be made from a series of arches, although other more economical structures are typically used today. Arch bridges are one of the oldest types of bridges and have been arounded for thousands of years. Arch bridges have great natural strength. They were originally built of stone or brick but these days are built of reinforced concrete or steel. The introduction of these new materials allows arch bridges to be longer with lower spans. Instead of pushing straight down, the load of an arch bridge is carried outward along the curve of the arch to the supports at each end. The weight is transferred to the supports at either end. These supports, called the abutments, carry the load and keep the ends of the bridge from spreading out. The load at the top of the key stone makes each stone on the arch of the bridge press on the one next to it. This happens until the push is applied to the end supports or abutments, which are embedded in the ground.
For every action there is an equal and opposite reaction. The ground which pushes back on the abutment create a resistance which is passed from stone to stone, until it is eventually pushing on the key stone which is supporting the load.
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 167 feet (51 m) and span of 123 feet (37 m), is the world's first wholly stone open-spandrel segmental arch bridge, allowing a greater passage for flood waters. Bridges with perforated spandrels can be found worldwide, such as in China (Zhaozhou Bridge, 7th century).
Truss Bridge:Truss is member consisting connected elements to form triangular units. In case of truss bridge the super structure is provided with trusses. Generally, trusses are made of steel. There are several types of trusses are available.
A truss bridge is a bridge whose load-bearing superstructure is composed of a truss, a structure of connected elements usually forming triangular units. The connected elements (typically straight) may be stressed from tension, compression, or sometimes both in response to dynamic loads. Truss bridges are one of the oldest types of modern bridges. The basic types of truss bridges shown in this article have simple designs which could be easily analyzed by 19th and early 20th-century engineers. A truss bridge is economical to construct because it uses materials efficiently. Truss bridges, which do not have the redundant web plate portion that girder bridges do, are an extremely rational, efficient bridge type adopting a structure made up of a combination of thin members that convey only axial force. Some types of truss bridges are named after their patent holder, such as the Howe truss, the Pratt truss, the Fink truss, and the Bollman truss. Today, the Warren truss is most widely adopted. The applied span of truss bridges is generally 50 to 110 meters, and the Quebec Bridge (Canada; 1917) is the longest truss bridge in the world, with a span length of 549 meters. JFE Engineering has great experience in manufacturing and erecting truss bridges.
Name
Tsukuba Express Tonegawa Bridge
Year completed 2003 Bridge type Client
Through type 3-span continuous double-track truss bridge, etc. Japan Railway Construction Public Corporation
Bridge length 897 m Features
Railway bridge
Suspension Bridge:In case of Suspension bridge, deck slab is suspended with the help of cables and suspenders. These will give good appearance. For long span bridges, this type of suspension is suitable. Suspension bridges consist of main towers, cables, girders, and anchorages. Girders come in the truss girder type, which is adopted mainly in the U.S., and the lightweight box girder type, which was developed in the U.K. and applies aerodynamic principles. Suspension bridges are a type of bridge that is generally adopted as a very long bridge with an effective span of about 150 to 2000 meters. JFE Engineering has manufactured and constructed a large number of suspension bridges to date both in Japan and overseas, including the Akashi Kaikyo Bridge, which is the longest suspension bridge in the world (center span: 1991 meters).
Name
Akinada Bridge
Year completed 1999 Bridge type Client
Suspension bridge Hiroshima Prefecture
Bridge length 1,175 m
Name
Akashi Kaikyo Bridge
Year completed 1997 Bridge type Client
Suspension bridge Honshu-Shikoku Bridge Authority
Bridge length 3,911 m
Longest suspension bridge in the world 780 N/mm2 grade high tensile steel with low weld crack sensitivity
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Features
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used
Cable Stayed Bridge:A cable-stayed bridge has one or more towers (or pylons), from which cables support the bridge deck. A distinctive feature are the cables or stays, which run directly from the tower to the deck, normally forming a fanlike pattern or a series of parallel lines. This is in contrast to the modern suspension bridge, where the cables supporting the deck are suspended vertically from the main cable, anchored at both ends of the bridge and running between the towers. The cable-stayed bridge is optimal for spans longer than cantilever bridges and shorter than suspension bridges. This is the range where cantilever bridges would rapidly grow heavier if the span were lengthened, while suspension bridge cabling would not be more economical if the span were shortened. Cable-stayed bridges have a structure with several points in each span between the towers supported upward in a slanting direction with cables, and consist of main towers, cables, and girders. Main towers are classified into such types as single-column, double-column, H-shaped, Ashaped, inverse Y-shaped, portal, and diamond. Cabling methods include single-plane suspension, double-plane suspension, fan pattern, and harp pattern. In general, the span applied to cable-stayed brides ranges from about 130 to 500 meters. JFE Engineering has manufactured and constructed a large number of cable-stayed bridges to date both in Japan and overseas, including the Tatara Bridge (center span: 890 meters), which was the longest cablestayed bridge in the world at the time of its completion.
Name
Shinminato Bridge
Year completed 2011 Bridge type Client
Cable-stayed bridge Ministry of Land, Infrastructure, Transport and Tourism Hokuriku Regional Development Bureau
Bridge length 600 m
5-span continuous composite cable-stayed bridge Cantilever erection by floating crane and traveler crane One of the longest cable-stayed brides on the Sea of Japan side
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Features
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Name
IRR, Thailand
Year completed 2006 Bridge type Client
Cable-stayed bridge Ministry of Transport, Thailand
Bridge length South bridge: 702 m, north bridge: 576 m Features
Name
500-ton large blocks lifted and erected North and south bridges erected simultaneously
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Daishi Bridge
Year completed 2006 Bridge type Client
Cable-stayed bridge City of Kawasaki
Bridge length 547 m Structure with skew angle main towers and main girders ・
Features
Pseudo 3-span cable-stayed bridge created by two 2-span parallel
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cable-stayed bridges
Moveable Bridge:A moveable bridge, or movable bridge, is a bridge that moves to allow passage for boats or barges. In American English, moveable bridge and drawbridge are synonymous, and the latter is the common term, but drawbridge can be limited to the narrower, historical definition used in some other forms of English, in which drawbridge refers only to a specific type of moveable bridge. An advantage of making bridges moveable is the lower cost, due to the absence of high piers and long approaches. The principal disadvantage is that the traffic on the bridge must be halted when it is opened for passage of traffic on the waterway. For seldom-used railroad bridges over busy channels, the bridge may be left open and then closed for train passages. For small bridges, bridge movement may be enabled without the need for an engine. Some bridges are operated by the users, especially those with a boat, others by a bridgeman (or bridge tender); a few are remotely controlled using video-cameras and loudspeakers. Generally, the bridges are powered by electric motors, whether operating winches, gearing, or hydraulic pistons. While moveable bridges in their entirety may be quite long, the length of the moveable portion is restricted by engineering and cost considerations to a few hundred feet. There are often traffic lights for the road and water traffic, and moving barriers for the road traffic .
Built from 1886 till 1894, this symbol of London is a combined bascule and suspension bridge in London, over the River Thames. It is close to the Tower of London, from which it takes its name. Tower Bridge is one of the most famous bridges in the world and the most famous movable bridge. The lower deck which is the bascule deck can open to an angle of 86 degrees in just 5 minutes. The two parts of the deck are counterbalanced by two bascules weighing over 1,000 tons each
Pedestrian Bridge:A footbridge (also a pedestrian bridge, pedestrian overpass, or pedestrian overcrossing) is a bridge designed solely for pedestrians. While the primary meaning for a bridge is a structure which links "two points at a height above the ground", a footbridge can also be a lower structure, such as a boardwalk, that enables pedestrians to cross wet, fragile, or mashy land. Bridges range from stepping stones –possibly the earliest man-made structure to "bridge" water –to elaborate steel structures. Another early bridge would have been simply a fallen tree. In some cases a footbridge can be both functional and a beautiful work of art. For rural communities in the developing world, a footbridge may be a community's only access to medical clinics, schools and markets. Simple suspension bridge designs have been developed to be sustainable and easily constructed in such areas using only local materials and labor. An enclosed footbridge between two buildings is sometimes known as a skyway. Bridges providing for both pedestrians and cyclists are often referred to as green bridges and form an important part of a sustainable transport system.
Bridge view
Carries
Pedestrians
Crosses
High-Speed Rail
Locale
Lleida (Spain)
Owner
ADIF
Maintained
Lleida Municipalily
by
Characteristics
Design
tied-arch bridge
Material
GFRP
Total length
38 m
Width
3m
Longest
38 m
span
History
Designer
Pedelta Structural Engineers
Engineering
Juan Sobrino and Javier Jordan
design by
Opened
2001
Train Bridge:Road –rail bridges are bridges shared by road and rail lines. Road and rail may be segregated so that trains may operate at the same time as cars (e.g., the Sydney Harbour Bridge). The rail track can be above the
roadway or vice versa with truss bridges. ... Road –rail bridges are sometimes called combined bridges The Chenab
bridge
a
steel and concrete
arch
bridge under
construction between Bakkal and Kauri in the Reasi district of Jammu and Kashmir in India. When finished, the bridge will span the Chenab River at a height of 359 m (1,178 ft) above the river, making it the world's highest rail bridge.
Pipeline Bridge:A pipeline bridge is a bridge for running a pipeline over a river or another obstacle. Pipeline bridges for liquids and gases are, as a rule, only built when it is not possible to run the pipeline on a conventional bridge or under the river. However, as it is more common to run pipelines for centralized heating systems overhead, for this application even small pipeline bridges are common.
Hegigio Gorge Pipeline Bridge was world's highest bridge from 2005 to 2009. It was also world's highest pipeline bridge. The bridge is 1,289 ft in height and has a length of 1,540 ft.
Glass Bridge:Zhangjiajie Glass Bridge is a bridge in Zhangjiajie, China, above the Wulingyuan area. The bridge, built as an attraction for tourists, is glassbottomed and is transparent. When it opened it was the longest and tallest glass bottomed bridge in the world. The bridge, opened to the public on August 20, 2016, measures 430 metres in total length and 6 metres in breadth, and is suspended about 300 metres above the ground. The bridge spans the canyon between two mountain cliffs in Zhangjiajie National Forest Park in China's central Hunan province. It is designed to carry up to 800 visitors at a time. The bridge was designed by Israeli architect Haim Dotan. To build the bridge, engineers erected 4 support pillaors on the edges of the walls of the canyon. The bridge is made of a metal frame with more than 120 glass panels. Each of these panels is 3-layered and is a 2-inch-thick slab of tempered glass. There are 3 long swings attached to the underside of the bridge. Also there is a provision for making a 285 metre bungee-jump. This is considered to be highest such jump in the world. According to the Management Committee of the Bridge, the bridge has set ten world records spanning its design and construction. The record as longest glass bridge has since passed to a glass bridge in the Hongyagu Scenic Area hebei.
On September 2, 2016, just 13 days after the bridge was opened, the authorities put out a notice saying that they are closing the bridge due to overwhelming visitor traffic. The bridge, designed to hold 800 people at a time and expected to be visited by about 8,000 people per day, had reportedly attracted more than 80,000 visitors per day. The authorities said that the government decided to suspend operations due to the "urgency to improve and update" the attraction, including its car parks, ticket-booking system, and customer service. The bridge reopened on September 30, 2016
Zhangjiajie Glass Bridge
Coordinates
29.3987°N 110.6982°E Coordinates: 29.3987°N 110.6982°E
Carries
Footbridge
Locale
Zhangjiajie, Hunan, China Characteristics
Design
Suspension
Material
Steel
Width
14 m (46 ft)
Height
360 m (1,180 ft)
Longest span
430 m (1,410 ft)
Clearance
300 m (980 ft)
below History Opened
August 20, 2016 Statistics
Daily traffic
8,000
Under Sea Bridge:An undersea tunnel is a tunnel which is partly or wholly constructed under a body of water. They are often used where building a bridge or operating a ferry link is impossible, or to provide competition or relief for existing bridges or ferry links. Thames foot tunnel" redirects here. For other tunnels, see Tunnels underneath the River Thames.
The Thames Tunnel is an underwater tunnel, built beneath the River Thames in London, connecting Rotherhithe and Wapping. It measures 35 feet (11 m) wide by 20 feet (6 m) high and is 1,300 feet (396 m) long, running at a depth of 75 feet (23 m) below the river surface measured at high tide. It was the first tunnel known to have been constructed successfully underneath a navigable river and was built between 1825 and 1843 using Marc Isambard Brunel's and Thomas Cochrane's newly invented tunnelling shield technology, by Brunel and his son Isambard Kingdom Brunel. The tunnel was originally designed for horse-drawn carriages, but was never used for that purpose. Since 2010 it forms part of the London Overground railway network under ownership of Transport for London.
