Famous Bridges
Each of the following bridges is famous in its own right. A bridge may receive acclaim because of its longevity, or perhaps simply for its beauty. It may have been a pivotal point in a battle. It also could have set the standard in a new type of design. Most bridges, by their function, allow for economic growth, improved communication among people, and aid in travel. Whichever of the previous reasons applies to the bridges noted below, these famous bridges tell who we are. Many have become the hallmark, identifying a given location. They are our structural art. The following bridges are discussed in chronological order.
*Tarr Steps- The first is the Tarr Steps, the age of which is unknown. These types of bridges "were built by pre-historic man in both the Bronze Age and Iron Age." 26 Located in Somerset, England this bridge is known as a stone clapper. The word clapper has origins in French, Latin, or Anglo-Saxon meaning "pile of stones". 27 The piers had cutwaters to redirect the water. It is believed the devil made it because the stones were not indigenous to Exmoor. People were not to cross it, "Romans avoided it". 28 Superstition surrounded it. It is made of granite, 55 meters in length, with 17 blocks for beams.
*Xeres I- In 480 BC, Xerxes' I, a Persian ruler, had his army build a pontoon bridge at Hellespont. This bridge was constructed from using more than six hundred ships. Two rows of ships were configured, 360 on the Black Sea side and 314 on the other. They were tied slantwise on one side, and at right angles on the other, to create less strain. The ships were tied together with cables of flax and papyrus, and then planks were added, followed by brush, then soil. 29 The army took seven days and nights to cross it!
* The Anji Bridge- This bridge was built from 605-617. It means "Safe Crossing" and spans the Xiache River in China. It was built by architect Li Chun. Built with open spandrels, this design preceded similar European designs by 700 years. Another engineering innovation was that Li Chun "used x dove tails in vertical joints" 30 During the cold winters of construction the builders formed an ice path by pouring water and letting it freeze. Then they would be able to slide the stones from the quarry to the construction site. 31
*The An Ping Bridge- This bridge is in the Fujian Province of China and is the world's longest stone slab clapper, bridge. It is comprised of "331 boat-shaped piers, supporting innumerable parallel stones slabs" 32 The largest of these slabs weighs 25 tons. Built from1138-1152, it was1.25 miles long. It was the longest bridge in China until 1905.
*The Bridge d' Avignon- The d' Avignon bridge was built in France from 1177 thru 1187. In 1177, Benoit, a shepherd boy, had a vision that God told him to build a bridge. When questioned by the bishop, Benoit lifted a huge stone and carried it to the river where the bridge was to be. He was told by the Bishop to build the bridge. He built it in a V shape to accommodate the spring flooding. Its elliptical arches allowed for narrower piers. The tall arches allowed for a higher narrow roadway. The height accommodated flooding. The narrow roadway made it easier to defend against enemies. It has a chapel, to St. Nicholas, that is located in the 2 nd pier. In this chapel, Saint Benoit (later canonized) is buried. The chapel was used for meeting of the clergy, as well as prayer. It was built in 10 years time and without mortar. In 1226, Louis VIII ordered it destroyed. The town rebuilt the bridge but did not do as good of a job as the original builders. Flooding in the 17 th Century partially destroyed it. Today only four arches remain.
*The Rialto Bridge- This bridge located in Venice, Italy was built from 1588 until 1591. In the 16 th century, Renaissance artists such as Michelangelo and Palladio competed to design the bridge in Venice's Grand Canal at Rialto. Antonio da Ponte's design won with a single arch bridge. The bridge has shops on each side with a road in the center. Having survived natural disasters, it still stands today as a symbol of Venice. It is a very famous landmark in Italy.
*The Coalbrookdale Iron Bridge- This bridge is located in Coalbrookdale England and was built from 1776-1779. It was the first large bridge made completely of cast iron. This bridge symbolizes the beginning of the Industrial Revolution. The 100 ft. span used screws as in wooden bridges, not bolts. When it was the only bridge to survive the flood of 1795, this new material was appreciated even more. It is still standing, but closed to traffic.
*The Britannia Bridge-Built in 1850, this bridge is in Wales. The bridge was made of two rectangular wrought iron side by side tubes. One of the biggest obstacles was putting the tubes in place. This was accomplished by floating them on pontoons during a high tide and then hoisting them up. 33 This type of bridge is a prerequisite to tube section bridges of today.
*The Brooklyn Bridge- This famous bridge crosses the East River in New York City. Bridge designer, John Roebling, a German immigrant, died of tetanus a few weeks after his foot was injured while surveying the construction site. His son, Washington Roebling, completed the job. One of the biggest obstacles was building the two towers. Another obstacle was that it took three years to build the caissons. From inspecting the foundation, W. Roebling got caisson disease (the bends or decompression illness) in 1872, which left him incapacitated. He supervised the construction from his apartment window which overlooked the site. His wife, Emily, acted as his messenger to see the job completed. Roebling "perfected the process of spinning cable wires". 34 In 1883 when completed, it was the world's longest span. It was a huge achievement and still stands as a symbol of New York, connecting Manhattan and Brooklyn.
*The Forth Bridge- This steel bridge is in Scotland. Sir Benjamin Baker and Sir John Fowler designed this bridge to withstand wind pressure five times that of the Tay Bridge (see Bridge Failures). Completed in 1890, and still in use today, this was Europe's first all steel rail bridge. It is the second longest cantilever in the world. Painted International Orange, it is always being repainted and checked for corrosion.
*The Tower Bridge- Completed in 1894, and located in London, its steel frame construction is covered with ornate Victorian masonry. This double lift bridge, the only movable one on the Thames, rises in 1.5 minutes. When it was first built it was criticized as "a monstrous and preposterous architectural sham". 35 Now as Eric de Mare said, that the British "have grown fond of the old fraud". It has two steel walkways on top that were closed in 1909 when anti-aircraft cannons were placed there. The walkway was reopened in 1982. 36
*The George Washington Bridge- This bridge is in New York City was built from 1927 to 1931. A suspension bridge designed by Othmar Ammann in 1931; its span of 3500 ft. doubled the previous record. 37 The towers were supposed to be covered in masonry, but because of the Great Depression, it was left showing the metal structure of the towers. Another cost saving measure was to use the cable suspension method, instead of chain suspension. Designed with two decks, the top was to have eight lanes and two walkways the bottom was to be for local trains. In 1962 six bottom lanes where added.
*The Sydney Harbor Bridge- This bridge is in Australia. Nicknamed "the old coat hanger", it opened in 1932. Influenced by Lindenthal's Hell Gate Bridge in New York, this arch bridge was built by cantilevering out from the banks, then joined in the center. Steel cables support the deck. It is the widest bridge in the world with 4 rail, 8 traffic lanes, and a pedestrian walkway. 38
*The Golden Gate Bridge- This famous landmark is located in San Francisco, California. It was designed by Joseph Strauss and opened in 1937. With 4200 ft. between the towers, it was the longest span in the world when it opened. Although the setting of the bridge is beautiful, the environmental challenges were harsh. The southern pier was to be built in water that was cold and deep. Caissons could not be built because the trestle roadway kept being destroyed. After several attempts were abandoned, a cofferdam was built. Architect Irving Morrow chose to paint it red.
*The New River Gorge Bridge- This bridge is in West Virginia and was completed in 1977. It is the longest arch bridge in the world. 39 It is a 1700 ft. steel deck arch. It has four lanes of traffic, 876 ft above the river.
*The Akashi Kaikyo Bridge- Located in Japan, it was completed in 1998. This bridge was built to withstand severe environmental factors. Supposedly, it can withstand gale winds, earthquakes, and tidal waves. It is built with truss supports under the roadway to decrease wind resistance. It also has dampening units in the towers that swings the bridge in the opposite direction from the wind. It is built to withstand winds up to 180 M.P.H. and earthquakes.
*The Puente del Alamillo Bridge- Designed by Santiago Calatrava, for the Expo "92 in Seville, this bridge is considered an outstanding accomplishment, in that Calatrava
combines the beauty of architecture with the necessities of design. It is 200m. long with a 58 degree backwards angular steel tower. The span is suspended with 13 twin cables.
*The Confederation Bridge- This bridge, in Canada, was built in 1997. The world's longest continuous span, made up of 44 spans, it connects the Northumberland Strait between Prince Edward Island and New Brunswick. According to Federal, criteria it must stand for 100 years as is. This bridge has to overcome the obstacle of ice to the bridge, and not "impede ice" during the spring thaws. 40 Lifestyles of the people have been changed by this bridge because they now are no longer so isolated.
The aforementioned bridges will be used to introduce students to the evolution of bridge building. Through researching these bridges, they will gain an understanding of how materials, the environment, and technology have made them possible.
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