Проект на тему «How to read bridges»

МБОУ «Средняя общеобразовательная школа №51

«Центр образования» города Рязани

Проект на тему

«How to read bridges»

Секция: Иностранные языки (Английский язык)

Работу выполнили:

Михайлова Ася,

Хрюкова Вика

Ученики 6А класса

Руководитель:

Кащеева М.А.

Рязань, 2014

Content

• Introduction

Reasons

Aims

Actuality

Research

• What is a bridge?

- definition

- etymology

• History

• Types of bridges

Bridges by structure

Fixed or moveable bridges

Bridge types by use

Bridge types by material

Bridges with unusual names

Guinness World Records

• Architects & Engineers

• The most amazing and unusual bridges

• Bridges as a mythic symbol and a philosophical contest

• Bridge proverbs and quotes

• Conclusion

• Attachment

Introduction

Bridges touch all our lives – every day a lot of people are likely to cross or to go under the bridge. But how many of us stop to consider how the bridge works and what sort of people designed or built it?

When we were in St. Petersburg we had to cross some bridges. We liked the Palace Bridge, the Hermitage Bridge, the Trinity Bridge, etc. We also liked the Picturesque (Zhivopisny) Bridge in Moscow. We’ve learned about the Russky Bridge, opened in July 2012 in Vladivostok, which became the second tallest cable-stayed bridge in the world (320,9 meters). It made us wonder about bridges in general and how long they have been around.

Ever since the dawn of time man has been trying to cross things – oceans, mountains, deserts. It’s in our blood. Crossing a river with a bridge can’t be all that exciting … or can it?

Reasons

We have decided to choose this theme because these constructions exert a powerful hold on our imagination and just fascinate us.

Aims

• Explore how we can read a bridge like a book

• Understand how they work

• Try to understand the difference between old and modern constructions

• Broaden our understanding of the world and bridge building

• Learn to appreciate its aesthetic, social, and engineering value

Actuality

We believe that bridges are among the most beautiful structures created by man. Not only the picturesque old stone bridges seen in rural settings, but the bridges of the railway age and the twentieth and the twenty first centuries can also be attractive to the eye whether built in concrete, iron or steel.

They are among the most complex architectural structures. That is why the creation of each bridge is a challenge to the architect, designer and engineers who need to the maximum use of their knowledge and talents to build a really robust and elegant structure.

That’s why we are sure that this theme may be interesting to our schoolmates. We hope our project work arouse your interest in these architectural structures and also broaden your outlook.

Research

Some questions that arose from our experience

What bridges do you know?

What types of bridges do you know?

It turned out that we know very little about bridges and even less about their types.

So, we’ve decided to find out everything we can about it and tell our schoolmates about it.

Bridge is not a construction but it is a concept, the concept of crossing over large spans of land or huge masses of water, and to connect two far-off points, eventually reducing the distance between them. The bridge provides passage over the obstacle of small caverns, a valley, road, body of water, or other physical obstacle. Designs of bridges vary depending on the nature of the terrain and the function of the bridge and where it is constructed.

The Oxford English Dictionary traces the origin of the word bridge to an Old English word brycg, of the same meaning, derived from German root brugj?

History

Whose idea was it?

There is not a specific person to credit with the invention of the bridge, but it dates back to ancient times.

The first bridges were believed to be made by nature — as simple as a log fallen across a stream. The first bridges made by humans were probably spans of wooden logs or planks and eventually stones, using a simple support and crossbeam arrangement.

We have found out that the earliest bridge was built on the Nile about 2650 BC. But can we believe it? The earliest written record of a bridge is the one build across the Euphrates around 600BC described by Herodotus, the 5th Greek historian.

The Indian Epic literature Ramayana provides mythological accounts of bridges constructed from India to Sri Lanka by the army of Sri Rama, the mythological King of Ayodhya.

The recent satellite photograph depicts the existence of this bridge, referred to in Ramayana.

Before pre-historic people began to build the crudest shelter for themselves they bridged streams. Trees that have fallen across the stream from bank to bank acted as bridges. The wandering tribe that first deliberately made a tree fall across a stream were the first bridge builders.

Observing monkeys swing of the several vines, led to connecting parallel cables with some sort of cross pieces, to support as bridges. Later hand grips were proved which led to suspension bridges. 

Rope bridges, a simple type of suspension bridge, were used by the Inca civilization in the Andes Mountains of South America.

The first bridges were natural of huge rock arch that spans. The first man-made bridges were tree trunks laid across streams in girder fashion, flat stones, and festoons of vegetation, twisted or braided and hung in suspension. These three types – beam, arch, and suspension – have been known and built since ancient times and are the origins from which engineers and builders derived various combinations such as the truss, cantilever, cable-stayed, tied-arch, and moveable spans.

Bridges of twisted vines and creepers were found in many parts of India. Deep in the rainforests of the Indian state of Meghalaya, bridges are not built, they’re grown. Ancient vines and roots of trees stretch horizontally across rivers and streams, creating a solid latticework structure strong enough to be used as a bridge. Since the area receives around 15 metres of rain every year, a normal wooden bridge would quickly rot.  But because the growing bridges are alive and still growing, they actually gain strength over time.  For more than 500 years locals have guided roots and vines from the native Ficus Elastica (rubber tree) across rivers, using hollowed out trees to create root guidance systems. When they roots and vines reach the opposite bank they are allowed to take root.  In time, a sturdy living bridge is produced. Some can take ten to fifteen years to become fully functional. 

Wooden bridges are some of the most ancient. Suspension bridges had been known in China as early as 206 BC.

Chinese built big bridges of wooden construction, and later stone bridges, and the oldest surviving stone bridge in China is the Zhaozhou Bridge built around 605 AD during the Sui Dynasty.

The ancient Romans were the greatest bridge builders of antiquity. They used cement, – called pozzolana consisting of water, lime, sand, and volcanic rock, which reduced the variation of strength found in natural stone.

Though extremely versatile, wood has one obvious disadvantage and during the 18th century there were many innovations in the design and a major breakthrough in bridge technology came with the erection of the Iron Bridge in Coalbrookdale in England during 1779, using cast iron for the first time as arches to cross the river Severn.

With the Industrial Revolution, steel, which has a high tensile strength, replaced wrought iron for the construction of larger bridges to support large loads, and later welded structural bridges of various designs were constructed.

Bridges are described in many different ways. If we try to capture all of these types mentioned in the internet our list will be very long and confusing. To begin to read a bridge we have found some principles which help us classify them.

Types of Bridges

Bridges by Structure

• Arch bridges – these bridges uses arch as a main structural component (arch is always located below the bridge, never above it). They are made with one or more hinges, depending of what kind of load and stress forces they must endure. Examples of arch bridge are “Old Bridge” in Mostar, Bosnia and Herzegovina and The Hell Gate Bridge in New York.

• Beam bridges – Very basic type of bridges that are supported by several beams of various shapes and sizes. They can be inclined or V shaped. Example of beam bridge is Lake Pontchartrain Causeway in southern Louisiana.

Iconic Beam Bridges of the world

The following is a quick list of famous bridges of the world. Now, though the following bridges are defined to be beam bridges, we will find that some of the really long ones typically have a suspension bridge in between them or have some other engineering design such as a truss bridge somewhere in between, as an engineering enhancement.

1. Manchac Swamp Bridge, United States
The Manchac swamp bridge is located in Louisiana is the 8th longest bridge in the world and 2nd longest in the United States, which carries Interstate 55 across the swamps. The engineering structure of this bridge is such that it's abutments are concrete trestles which are two pillared. The total length of the bridge is 22.80 miles (36.69 km) and it's piles or abutments were driven 250 feet (76 m) into the swamps. The cost of one single mile amounted to $7 million.

2. Tianjin Grand Bridge, People's Republic of China
The Tianjin Grand bridge is one of the youngest and also the second longest of all bridges and is a sea link. This bridge has small suspended portions with the remaining long portions being regular beam bridges. The Tianjin Grand bridge carries the Beijing-Shangai high speed railway for 133.7 kilometers (83.0773284 miles).

3. Lake Pontchartrain Causeway, United States
The Lake Pontchartrain causeway is a dual bridge which crosses the Lake Pontchartrain, Louisiana. This bridge is the 7th longest bridge in the world and also the longest bridge in the United States, running for 23.83 miles (38.35 km). This bridge has a Bascule in between which enables the passage for water navigation.

4. Donghai Bridge, People's Republic of China
Also known as the East Sea Grand Bridge, the Donghai Bridge is the longest sea crossing bridge and is of substantial economic importance for the People's Republic of China as it acts as the connection between mainland China and Yangshan, off-shore deep water port. The bridge runs for 32.5 kilometers (20.2 miles). The bridge has a some cable stayed portion for water navigation.

5. King Fahd Causeway, Bahrain and Saudi Arabia
The King Fahd causeway was a mammoth project which had a cost of USD 1.2 billion. The causeway bridge runs for 25 km (16 miles) and remarkable long width of 23 m (75 ft) which is taken up by 4 lanes. The construction of the bridge lasted from 1981 to 1986.

Some of the other beam bridges include:
Vasco da Gama Bridge, Portugal
Confederation Bridge, Canada
Great Belt bridge, Denmark
Chapel Bridge, Switzerland
Chengyang Bridge, People's Republic of China
On the whole, any bridge which has a bridge deck supported by abutments is a beam bridge. If we observe properly, a majority of bridges are beam bridges with some hybrid engineering being inducted in them.

• Truss bridges – very popular bridge designs that uses diagonal mesh of posts above the bridge. The two most common designs are the king posts (two diagonal posts supported by single vertical post in the center) and queen posts (two diagonal posts, two vertical pots and horizontal post that connect two vertical posts at the top).

• Cantilever bridges – similar in appearance to arch bridges, but they support their load not trough vertical bracing but trough diagonal bracing. They often use truss formation both below and above the bridge. Example of cantilever bridge is Queensboro Bridge in New York City.

• Tied arch bridges – similar to arch bridges, but they transfer weight of the bridge and traffic load to the top chord that is connected to the bottom cords in bridge foundation. They are often called bowstring arches or bowstring bridges.

• Suspension bridges – bridges that use ropes or cables from the vertical suspender to hold the weight of bridge deck and traffic. Example of suspension bridge is Golden Gate Bridge in San Francisco.

• Cable-stayed bridges  – bridge that uses deck cables that are directly connected to one or more vertical columns. Cables are usually connected to columns in two ways – harp design (each cable is attached to the different point of the column, creating harp like design of “strings” and fan design (all cables connect to one point at the top of the column).

Fixed or moveable bridges

Fixed – Majority of bridges are fixed, with no moveable parts to provide higher clearance for river/sea transport that is flowing below them. They are designed to stay where they are made to the point they are deemed unusable or demolished.

Temporary bridges – Bridges made from modular basic components that can be moved by medium or light machinery. They are usually used in military engineering or in circumstances when fixed bridges are repaired.

Moveable – They have moveable decks, most often powered by electricity.

Types by use

Car Traffic – The most common type of bridge, with two or more lanes designed to carry car and truck traffic of various intensities.

Pedestrian – Usually made in urban environments, or in terrain where car transport is inaccessible (rough mountainous terrain, forests, etc.).

Double-decked – Built to provide best possible flow of traffic across bodies of water or rough terrain. Most offen they have large amount of car lanes, and sometimes have dedicated area for train tracks.

Train bridges – Bridges made specifically to carry one or multiple lane of train tracks.

Pipelines – Bridges made to carry pipelines across water or inaccessible terrains. Pipelines can carry water, air, gas and communication cables.

Viaducts – Ancient structures created to carry water from water rich areas to dry cities.

Commercial bridges – Modern bridges that host commercial buildings such as restaurants and shops.

Types by materials

Natural materials

Wood

Stone

Concrete and Steel

Advanced materials

Bridges with unusual names

Venice is known as the “City of Bridges”. About 400 bridges connect the 117 small islands and cross the 150 canals of the city. Some of these bridges have been dubbed with the most bizarre and unusual names, often linked to the history of famous, mysterious or less known sites and personages of Venice.

For example,

Bridge of Breasts

Fighting Bridge

Bridge of Barefoot

Bridge of Sighs, Venice / Bridge of Sighs, Oxford

Devil’s bridge

Bridge of Salvation/Assistance

The Bridge of Immortals, Huanghsan, China

There is a bridge named The Bridge to Nowhere. It is a concrete road bridge spanning the Mangapurua Stream in Whanganui National Park, North Island, New Zealand. It has no roads leading to it.

The Storseisudent Bridge, Norwegian is locally known as the drunk bridge. It is a cantilever bridge. It is 250 meters long. It was opened on 7 July, 1989. It looks very much as if you are in for icy bath as you plummet off its 23 meter height. But it is simply something of an optical illusion. The bridge is built in such a way that from a certain angle, as you approach, it looks as it is more a diving board than a bridge. It attracts many curious visitors. One can only imagine the creative spirit that overcame the architect as he sat at his desk. Why it is built in this way is a secret lodged in the mind of its architect. It seems to have a different shape from whichever angle you view it which is, perhaps, what makes it so special. Even when you can see the whole bridge it still looks, frankly, scary. The Bridge has been also popularized as “The road to nowhere” by Daily Mail in 2011.

Guinness World Records

World’s Longest

Danyang-Kunshan Grand Bridge on the Beijing-Shanghai High-Speed Railway in China (164,8 kilometers long)

Type: Viaduct (arches supported by piers)

World’s Tallest

Millau Viaduct over the River Tarn in southern France (343 meters high)

Type: Cable-stayed

World’s Highest

Siduhe Bridge (The Si Du River Bridge) is the highest bridge in the world. The heighest measurement from the bottom of the gorge is 1,550 ft (472m). The bridge is part of a new highway from Yichang to Chongqing – which opened to traffic on November 15^th, 2009.

Type: Suspension

World’s Oldest

Slab-stone bridge over River Meles in Izmir, Turkey (built in 850 BC)

Type: Single-arch

World’s Widest

San Francisco-Oakland Bay Bridge, the U.S. state of California. It crosses the San Francisco Bay between Yerba Buena Island and Emeryville.

Type: Self-anchored suspension bridge and viaduct

The builders of the Extreme Park in Sochi which is unique for Russia have finished the pedestrian bridge, which now claims to be the longest bridge in the world. The construction with the length of 440 m is built over a mountain gorge in Adler District at a height of 220 meters. 

      The authors of the project have already applied for the inclusion of the bridge over the Mzymta River (Mzymta is the largest river in Russia emptying into the Black Sea. Length: 89 kilometres ) into the Guinness Book of Records as the longest suspension pedestrian bridge in the world. 

      Its model passed the preliminary test in a wind tunnel with the seismic load of nine points before its assembly. The bearing of the bridge made of metal work will become a viewing platform of the highland park of extreme entertainment. 

Architects & Engineers

In general, bridges are designed by two different types of people. Architects are responsible for how a bridge looks while engineers are responsible for how the bridge works and is supported. There are a lot of things to consider when designing a bridge. Physics is a field of science that studies matter, energy, forces, and more. People who design bridges need to understand some important physics concepts in order to make a bridge that will be strong, stable, and secure over time. Some physics concepts that are considered when bridges are designed are compression and tension. These are both forces that happen every day on bridges and can act differently on different materials. Compression presses down or shortens an object. Tension stretches out or lengthens an object. In addition to being able to support lots of weight, a bridge must also be able to stand up to lots of different types of weather, like high winds and sometimes even earthquakes! Sometimes architects and engineers design special bridges that combine two or more types of bridges together to make the best possible bridge for a location. They have to be very careful to make sure the bridge design will still be stable and strong enough. Bridge designs must be tested quite well before a bridge is ever built. Today, engineers continue to test the limits of science and imagination. They experiment with innovative materials, designs and methods of construction. Their finished products move cars and trains. Have you heard of a wave bridge, a living root bridge or a fountain bridge? Beautiful and extremely unique bridges often serve as tourists' attractions. However, most of these strange bridges of the world also serve in their original purpose: to get people and vehicles from one point to another. The unusual bridges often have a great story behind them, with history and traditions connected to them. Some of these strange unusual bridges are pearls of modern technology; others have been treasured for hundreds of years.

So, now we’d like to tell you about the most beautiful and unusual bridges in the world.

Banpo Bridge, South Korea

From the vintage to the modern, this really awesome bridge is found in Seoul and crosses the Han river. The bridge itself was actually created in 1982 but in 2007 a project was launched to revive the area; in 2009 the project did just that. The Koreans had the amazing idea of adding fountains across both sides. During the day, the fountain shoots 190 tons of water per minute from each side of the bridge from its 380 nozzles. At night the color of the fountain will be transformed to a rainbow by the 10,000 LED lights which create various colorful effects. The water jets are dynamic and can move in time with the music, creating spectacular ever-changing displays. As well as being stylish, the bridge is also environmentally friendly and the water is pumped directly from the river itself and continuously recycled. In 2008 the fountain made it into the Guinness Book of World Records as the longest bridge fountain. This bridge is not only a triumph to Korea, but to architecture as well.

Henderson Waves Bridge, Singapore

The bridge was designed to look like waves, as you can guess by the name. It connects 2 of Singapore’s parks, Mount Faber Park and Telok Blangah Hill Park and has a stunning view of Singapore’s natural side. At night it is lit up to add more beauty to its already artistic design. Henderson Waves is made of steel and timber. Steel is needed for structural purposes, whereas timber celebrates the beauty of the parks that it connects while adding to its classy design. The bridge is equipped with seating, lounging and sight-seeing areas to compliment its surrounding view.

Khaju Bridge, Iran

The Khaju Bridge was built by the Persian King, Shah Abbas II, during the 17th century. It has 23 arches and the bridge also functions as a dam, controlling the waters of the Zayandeh river it looks over. The remains of stone seats, built for Shah Abbas II to sit on and admire the view, still remain. In the center, a pavilion was built exclusively for his pleasure, originally  as a tea house.

Tower Bridge, England

From one historical landmark to another, this time we head to Europe, England to be exact. In the 19th century, London Bridge was the only way of crossing the Thames river. As London grew, more bridges were added on the west side of London Bridge. The east side however become a busy port and it quickly became apparent that a new bridge was needed. Planning started in 1884 when a design was chosen from over 50 submissions. It took 8 years, 432 workers, and over 11,000 tons of steel to build what we know now as Tower Bridge. The Prince of Wales opened the bridge in 1894 and It helped relieve the stress of the east side. The bridge would become one of the worlds most recognized bridges due to it’s iconic design. It has 2 towers at the ends of each bank. The middle section of the bridge can raise up and down, to let ships sail past, which is done with the use of hydraulics. The bridge is not only an icon of London, but to the whole of the U.K.

Moses Bridge, Netherlands

Taking a break from the big and grand scale designs, this bridge is appropriately called the Moses Bridge because it splits the water in two…literally. The innovative design was built in a 17th century fortress. The fortress itself was being restored and a bridge was to be built across it but architects, not content with making the fortress so visible to its enemies, had other things on their minds. They decided to disguise it and put it under the moats waterline to make it almost invisible. It sits within the moat and allows people to cross virtually undetected from water level. This artistic design creates a great illusion that you are walking through water as the bridge blends in with the landscape. It is entirely made of wood and is waterproofed so there is no worries about getting your feet wet!

Chengyang Bridge, China

Nicknamed the “Wind and Rain Bridge” and hidden amongst the rice fields and mountains, this bridge is found in the Guangxi Province of China spanning the Linxi River. Built in 1916 by the Dong people, an ethnic minority in China, the bridge has five separate pagoda structures with porches and pavilions. The traditional Chinese architecture makes for a fantastic looking structure but the most amazing thing about this bridge is that during construction, not a single nail was used, relying instead on some amazing architectural tricks.

Millau Viaduct, France

This bridge is in the Guinness Book of World Records for being the tallest bridge in the world. It stands at an incredible 1,125ft tall to become an engineering masterpiece. The bridge gained international recognition as a major engineering feat and received the Outstanding Structure Award in 2006, one of the most prestigious prizes an architect can win. The New York Times described it as “a triumph of engineering” and the BBC called it “one of the engineering wonders of the 21st Century”. The president of France, Jacques Chirac, opened the bridge in 2004 which cost an estimated 394 million euros, or 524 million dollars. The bridge itself crosses over the Tarn River Valley in Millau and gives drivers some of the most stunning views in all of France, even rising above the clouds on some days!

The Falkirk Wheel, Scotland

It was opened in 2002. There is more to this bridge than it’s very futuristic design. This is the world’s first and only boat lift! That’s right; the structure can actually rotate 180 degrees and is equipped with two locks which have 168 m long tunnels that emerge at the ends of the 2 wheels. Boats at the bottom sail into these tunnels; the structure then rotates, lifting the boats up to the top of the canal. The bridges unique way of connect the canals and transporting boats makes it an exceptional feat of modern engineering.

Langkawi Sky Bridge, Malaysia

The Langkawi Sky Bridge can be accessed via cable car. The bridge is a 410 ft-long curved pedestrian bridge above Gunung Matchincang roughly 2,300 ft above sea level. Once you travel up the mountain via the the cable car, the bridge gives tourists the opportunity to view some of the most beautiful sights of the Malaysian mountains and rainforests.

Helix Bridge, Singapore

This bridge across the Singapore river is unique in how it was designed to look like the structure of DNA. Opened in 2010, the Helix Bridge is made mostly from steel and is illuminated at night by ribbons of LED lighting to compliment its unique design.

Bridges as a mythic symbol and a philosophical contest

But bridges are not only physical constructions. They help us express some of our deepest emotions. All through history people have expressed their awe, wonder, spirituality, and religious faith by building. Pyramids were a connection, a bridge between this world and the next. Churches and cathedrals contain soaring arches to reach out to the heavens and to bridge the roof.

Throughout the history bridges have been used as mystic symbols, the enigmatic connection between heaven and earth, between the natural and the supernatural. They are links between the known and the unknown, they are the places between places, they are part of how we try to deal with what we don’t understand.

According to the Greeks you cross a river with the cantankerous ferryman Charon. In Norse mythology you walk over a rainbow arch bridge called Bifrost. The Chinvat Bridge between hell and paradise in Zoroastrian myth was made by Mazda (God). The Telemni Yokuts of North America must cross a long frail bridge over a stream that separates them from the land of the dead. The Semang of Malaysia must navigate a bridge called Balan Bacham to get to the magical island of Belet. In ancient Rome, before Christianity, the pontifices were the priests who bridged the gap between gods and men.

Bridges have a philosophical meaning. We often say that life consists of ‘many bridges to cross’, or ‘don’t burn the bridge’. We speak of bridges when we think about understanding between people, nations, cultures, and religious faiths.

Bridge proverbs and quotes

Don’t cross the bridge until you come to it. (English proverb)

With a friend behind you have a safe bridge (Dutch bridge)

If man be a river, then woman will be a bridge. (Arab proverb)

A child is a bridge to heaven. (Persian)

As the wise man looks for a bridge the fool crosses the river. (Persian)

Where there is no bridge the smallest plank is of great value. (Hungarian)

If you destroy a bridge, be sure you can swim. (Swahili proverb)

It is better to build bridges than walls. (Swahili proverb)

Discipline is the bridge between goals and accomplishment. (Jim Rohn, American speaker and Author)

That is the road we all have to take – over the Bridge of Sighs into eternity. (Soren Kierkegaard, Danish Philosopher and Teologian).

Love is the bridge between two hearts.

Mistakes are the usual bridge between inexperience and wisdom. (Phylis Theroux)

Life is a bridge over the sea of changes. Do not build a house on it. (Sri Sathya Sai Baba)

Conclusion

We have learned a lot of interesting things about bridges. The main task of the bridge is functional, provide a means of crossing. But the aesthetic aspect has not been canceled. And many bridges are monuments of a bridge builder. We have come away thinking that we chose a great piece of art to look at and to study. We enjoyed doing our project work. We have learned about different types of bridges, how they have changed over time, how they have developed into what they are today. We’ve learned that a bridge is a mystic symbol and a philosophical concept.

Sources

1. David Blockley “Bridges” The Science and Art of the World’s Inspiring structures. – Oxford university press 2010.

2. 5 Bridge Types www.Architecturebychildren. Org

3. En.wikipedia.org/wiki/Bridge

4. List25.com/25-of-the-world’s-most-unuque-bridges

Types of bridges

Bridges are classified as Beam bridges, Cantilever bridges, Arch bridges, Suspension bridges, Cable stayed bridges and Truss bridges.

• Beam Bridge: A horizontal beam supported at its ends comprises the structure of a beam bridge. The construction of a beam bridge is the simplest of all the types of bridges.

Cantilever bridges are built using cantilevers—horizontal beams that are supported on only one end. Most cantilever bridges use two cantilever arms extending from opposite sides of the obstacle to be crossed, meeting at the center.

• The Arch Bridge is arch-shaped and has supports at both its ends. The weight of an arch-shaped bridge is forced into the supports at either end.

• The suspension bridge is suspended from cables. The suspension cables are anchored at each end of the bridge. The load that the bridge bears converts into the tension in the cables.

• The Cable-stayed Bridges like suspension bridges are held up by cables. However, in a cable-stayed bridge, less cable is required and the towers holding the cables are proportionately shorter. The longest cable-stayed bridge is the Sutong bridge over the Yangtze River in China.

• Truss bridges are composed of connected straight elements with the help of pin joints. They have a solid deck and a lattice of pin-jointed or gusset-joined girders for the sides. Early truss bridges were made of wood, and later of wood with iron tensile rods, but modern truss bridges are made completely of metals such as wrought iron and steel or sometimes of reinforced concrete.

 

Fixed or movable bridges

Most bridges are fixed bridges, meaning they have no moving parts and stay in one place until they fail or are demolished. Temporary bridges, such as Bailey bridges, are designed to be assembled, and taken apart, transported to a different site, and re-used. They are important in military engineering, and are also used to carry traffic while an old bridge is being rebuilt. Movable bridges are designed to move out of the way of boats or other kinds of traffic, which would otherwise be too tall to fit. These are generally electrically powered.

Double-decked bridges

Double-decked (or double-decker) bridges have two levels. The Tower Bridge is an example of a double-decked bridge, with the central section consisting of a low level bascule span and a high level footbridge.

Viaducts

A viaduct is made up of multiple bridges connected into one longer structure. The longest and some of the highest bridges are viaducts, such as the Lake Pontchartrain Causeway and Millau Viaduct.

Three-way bridges

A three-way bridge has three separate spans which meet near the center of the bridge. The bridge appears as a "T" or "Y" when viewed from above. Three-way bridges are extremely rare, with just 24 known to exist. The Tridge, Margaret Bridge, and Zanesville Y-Bridge are examples.

Bridge types by use

A bridge can be categorized by what it is designed to carry, such as trains, pedestrian or road traffic, a pipeline or waterway for water transport or barge traffic. An aqueduct is a bridge that carries water, resembling a viaduct, which is a bridge that connects points of equal height. A road-rail bridge carries both road and rail traffic. A bridge can carry overhead power lines as does the Storstrøm Bridge.

Some bridges accommodate other purposes, such as the tower of Nový Most Bridge in Bratislava, which features a restaurant, or a bridge-restaurant which is a bridge built to serve as a restaurant. Other suspension bridge towers carry transmission antennas.

Bridge types by material

The materials used to build the structure are also used to categorize bridges. Until the end of the 18th Century, bridges were made out of timber, stone and masonry. Modern bridges are currently built in concrete, steel, fiber reinforced polymers (FRP), stainless steel or combinations of those materials.

Moon Bridge in Beijing (8 photos)

Moon Bridge - is a curved crescent footbridge. Such bridges are typical of gardens of China and Japan. This moon bridge is made in such a way as to make a pathway for an imperial boat. The bridge got another name  due to its shape - the Camel's Hump Bridge. 

Bridges have been around ever since humans began to move themselves -- and their goods -- from one place to another. Early bridge engineers had to do little more than fell a tree across a ravine or stream, but they soon discovered that they could span greater distances and haul heavier loads by putting more time and energy into their structures.

Roman engineers perfected the stone arch and used it to buildaqueducts -- bridges that conveyed fresh water great distances -- and similar structures to carry traffic across streams and rivers. But the Industrial Revolution took bridge building to new heights and even greater lengths.

By the end of the 19th century, record-breaking bridges seemed to come fast and furious. The Brooklyn Bridge, completed in 1883, was the longest spanning bridge in the world -- until Scottish engineers completed the Firth of Forth Bridge just seven years later.

A new century brought longer, more amazing bridges. In 1937, the Golden Gate Bridge stretched its 8,981-foot (2,737-meter) back over the treacherous waters of the San Francisco Bay.

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This Leonardo Da Vinci’s Bridge can be seen spanning E18, the highway between Oslo, Norway and Sweden in the township of Ås. This stunning bridge was originally designed by Leonardo Da Vinci, the artist of the Renaissance, in 1502 but never built. It was 500 years after when the Norwegian artist, Vebjorn Sand took the idea of building the bridge. It was unveiled on October 31, 2001.

The bridge serves as a pedestrian bridge over a highway in the town of Ås. It spans about 220 ft. long with a height of 26 ft. The Leonardo Da Vinci’s bridge honors both the Renaissance artist and the contemporary artist of all time.

In 1502 Leonardo produced a drawing of a single span 720-foot (240 meter) bridge as part of a civil engineering project for Sultan Beyazid II of Constantinople. The bridge was intended to span an inlet at the mouth of the Bosporus known as the Golden Horn. Beyazid did not pursue the project because he believed that construction was impossible. Leonardo's vision was resurrected in 2001 when a smaller bridge based on his design was constructed in Norway

Leonardo da Vinci'nin had a vision in 1502:To construct the largest and most beautiful ridge that has ever been seen in the world.” “In 1502, the Sultan Bajazet II decided he needed a bridge. He commissioned none other than Leonardo da Vinci himself to design the bridge. Leonardo's design was strange in the extreme: a stone bridge in a single graceful arch, thin at the centre and widening both horizontally and vertically at the ends to join onto the land in a series of curves; the design is organic-looking and resembles the roots of a tree. The whole style of the bridge is a triumph of minimalism, totally unlike the baroque masterpieces popular in Europe at the time. Some details of Leonardo's design: ? Width at centre: 24m ? Height above sea at centre: 40m ? Span: 240m ? Total bridge length: 360m We don't know the Sultan's reaction to Leonardo's plans, but the bridge was never built.” Da Vinci’s design used the technology of his era. On the other hand, use and form of structural building components at a level far beyond its era is matchless. Two main carriers are observed in the arc form passing a space of 360m. Circulation platform stands on these main carriers. The starting point of our project is to preserve the original design conceptually; to explicate is structurally and in terms of material use. The main carrier carrying the main body has been established with pre-stressing steel girders. These girders separate from the main body on both sides and are fastened on the ground. The main structure on steel carriers sits on a base behind and this permits pedestrian and vehicle circulation from under the structure. The main body except for arc shaped steel carriers are covered with sandstone, the seating groups and barriers are made of massive wood. Linear illumination emphasizes the whole structural components. The bridge physically connects the two coasts and aims at brightening up social life. In this manner, it is aimed to relate Miniaturk (önemli tarihi ve modern yap?lar?n büyük ölçekte maketlerinin yer ald??? kal?c? sergi alan?) and the social activities foreseen in the southern coastal part with the ridge. There is a rowing and water sports club, eating facilities such as cafes and restaurants and recreation areas supporting these functions on the historical peninsula. Although the Da Vinci Bridge missed the opportunity to become one of the symbols of Istanbul, which has been the capital of the Byzantine and Ottoman Empires, it still carries the hope of being the modern symbol of a world city in terms of social and economic perspectives in which many cultures live together.

Bridges by Structure

• Arch bridges – These bridges uses arch as a main structural component (arch is always located below the bridge, never above it). They are made with one or more hinges, depending of what kind of load and stress forces they must endure. Examples of arch bridge are “Old Bridge” in Mostar, Bosnia and Herzegovina and The Hell Gate Bridge in New York.

• Beam bridges – Very basic type of bridges that are supported by several beams of various shapes and sizes. They can be inclined or V shaped. Example of beam bridge is Lake Pontchartrain Causeway in southern Louisiana.

• Truss bridges – Very popular bridge designs that uses diagonal mesh of posts above the bridge. The two most common designs are the king posts (two diagonal posts supported by single vertical post in the center) and queen posts (two diagonal posts, two vertical pots and horizontal post that connect two vertical posts at the top).

• Cantilever bridges – Similar in appearance to arch bridges, but they support their load not trough vertical bracing but trough diagonal bracing. They often use truss formation both below and above the bridge. Example of cantilever bridge is Queensboro Bridge in New York City.

• Tied arch bridges – Similar to arch bridges, but they transfer weight of the bridge and traffic load to the top chord that is connected to the bottom cords in bridge foundation. They are often called bowstring arches or bowstring bridges.

• Suspension bridges – Bridges that use ropes or cables from the vertical suspender to hold the weight of bridge deck and traffic. Example of suspension bridge is Golden Gate Bridge in San Francisco.

• Cable-stayed bridges – Bridge that uses deck cables that are directly connected to one or more vertical columns. Cables are usually connected to columns in two ways – harp design (each cable is attached to the different point of the column, creating harp like design of “strings” and fan design (all cables connect to one point at the top of the column).

Fixed or moveable bridges

• Fixed – Majority of bridges are fixed, with no moveable parts to provide higher clearance for river/sea transport that is flowing below them. They are designed to stay where they are made to the point they are deemed unusable or demolished.

• Temporary bridges – Bridges made from modular basic components that can be moved by medium or light machinery. They are usually used in military engineering or in circumstances when fixed bridges are repaired.

• Moveable – They have moveable decks, most often powered by electricity.

Types by use

• Car Traffic – The most common type of bridge, with two or more lanes designed to carry car and truck traffic of various intensities.

• Pedestrian – Usually made in urban environments, or in terrain where car transport is inaccessible (rough mountainous terrain, forests, etc.).

• Double-decked – Built to provide best possible flow of traffic across bodies of water or rough terrain. Most offen they have large amount of car lanes, and sometimes have dedicated area for train tracks.

• Train bridges – Bridges made specifically to carry one or multiple lane of train tracks.

• Pipelines – Bridges made to carry pipelines across water or inaccessible terrains. Pipelines can carry water, air, gas and communication cables.

• Viaducts – Ancient structures created to carry water from water rich areas to dry cities.

• Commercial bridges – Modern bridges that host commercial buildings such as restaurants and shops.

Types by materials

• Natural materials

• Wood

• Stone

• Concrete and Steel

• Advanced materials

World’s Longest

Danyang-Kunshan Grand Bridge on the Beijing-Shanghai High-Speed Railway in Chaina (164,8 kilometers long)

Type: Viaduct (arches supported by piers)

World’s Tallest

Millau Viaduct over the River Tarn in southern France (343 meters high)

Type: Cable-stayed

World’s Oldest

Slab-stone bridge over River Meles in Izmir, Turkey (built in 850 BC)

Type: Single-arch

World’s Widest

Port Mann Bridge over the Fraser river in British Columbia, Canada (more than 65 meter wide)

Type: Cable-stayed