A bridge is a structure built to span physical obstacles such as a body of water, valley, or road, for the purpose of providing passage over the obstacle. There are many different designs that all serve unique purposes 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:
These bridges uses arch as a main structural component (arch is always located below the bridge, never above it).
2.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
3.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).
4.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.
5.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.
6.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.
7.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).Among these types of Bridges, tallest bridge is built and it is MILAU VIADUCT
DESCRIPTION:
The Millau Viaduct (French: le Viaduc de Millau, IPA: [vjadyk dÉ™ mijo]) is a cable-stayed bridge that spans the valley of the River Tarn near Millau in southern France.
Designed by the French structural engineer Michel Virlogeux and British architect Norman Foster, it is the tallest bridge in the world with one mast's summit at 343.0 metres (1,125 ft) above the base of the structure.
It is the 12th highest bridge deck in the world, being 270 metres (890 ft)between the road deck and the ground below.Millau Viaduct is part of the A75-A71 autoroute axis from Paris to Béziers and Montpellier.
Construction cost was approximately €400 million. It was formally inaugurated on 14 December 2004, and opened to traffic on 16 December.The bridge has been consistently ranked as one of the great engineering achievements of all time.The bridge received the 2006 International Association for Bridge and Structural Engineering Outstanding Structure Award.
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