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The golden gate bridge

the golden gate bridge is one of the most famous bridges in the world. Internationally, it is a recognized symbol of San Francisco, California, and of the United States. But before i tell you more about it, let me explain the basics: What is a bridge? A link or connection between two objects - usually places either side of an obstacle, such as a river, chasm, or estuary. 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. Designs of bridges vary depending on the function of the bridge, the nature of the terrain where the bridge is constructed, the material used to make it and the funds available to build it.

Are all bridges alike? There are six main types of bridges: Truss bridges, Cantilever bridges, Arch bridges, suspension bridges, Cable stayed bridges and Beam bridges. Bridges are usually made of concrete, steel, cement, iron, wood, stone and/or metal. How is the span between their piers or towers? 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.

What social and/or political benefits can bridges provide to places? A bridge is designed for 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. Bridges can improve communication, popularity and the quality of life in the places they are built. Why were the bridges built? The first bridges were made by nature itself — as simple as a log fallen across a stream or stones in the river. The first bridges made by humans were probably spans of cut wooden logs or planks and eventually stones, using a simple support and crossbeam arrangement. Some early Americans used trees or bamboo poles to cross small caverns or wells to get from one place to another. A common form of lashing sticks, logs, and deciduous branches together involved the use of long reeds or other harvested fibers woven together to form a connective rope capable of binding and holding together the materials used in early bridges.

Did they provide benefits? To whom? Why? Bridges provide benefits to people living on either side of the bridge. Some of the benefits of bridges are obvious: supplies of food and traded goods can get across an obstacle or through difficult terrain in a shorter time. This means that, in economic terms, the cost of travel and trade falls and the financial benefits of increased social cohesion and sharing resources rise. Other longer-term payoffs from easier travel, which is crucially dependent on good bridges, come as a result of increased opportunities to share ideas – intellectual, political and religious. Today bridges allow easy travel across major rivers and estuaries, over the new obstacles of motorways and railway lines, and between neighbouring islands. International trade and travel depend on shipping and air routes, but efficient distribution networks depend on bridges

Now let me tell you all about the Golden gate bridge.

The Golden Gate Bridge is a suspension bridge spanning the Golden Gate, the opening of the San Francisco Bay into the Pacific Ocean. As part of both U.S. Route 101 and California State Route 1, the structure links the city of San Francisco, on the northern tip of the San Francisco Peninsula, to Marin County. The color of the bridge is officially an orange vermillion called international orange.The color was selected by consulting architect Irving Morrowbecause it complements the natural surroundings and enhances the bridge's visibility in fog. Before the bridge was built, the only practical short route between San Francisco and what is now Marin County was by boat across a section of San Francisco Bay. The main reason people wanted to build a bridge was to connect San Francisco to Marin County. San Francisco was the largest American city still served primarily by ferry boats. Because it lacked a stable and permanent connection with communities around the bay, the city's growth rate was below the national average. The golden gate bridge is a suspension bridge, This type of bridge has cables suspended between towers, plus vertical suspender cables that carry the weight of the deck below, upon which traffic crosses. This arrangement allows the deck to be level or to arc upward for additional clearance. The suspension cables must be anchored at each end of the bridge, since any load applied to the bridge is transformed into a tension in these main cables. When completed in 1937, the Golden Gate Bridge had the longest suspension bridge main span in the world, at 4,200 feet (1,280.2 m). Since 1964, its main span length has been surpassed by eight other bridges. However, it still has the second longest main span in the United States, after the Verrazano-Narrows Bridge in New York City.The total length of the Golden Gate Bridge, including approaches from abutment to abutment, is 8,981 feet (2,737 m). At 692 feet (211m) (above water), the Golden Gate Bridge also had the world's tallest suspension towers when built. It held that status until 1998, with the completion of bridges in Denmark and Japan. The golden gate bridge is made of steel. The weight of the roadway is hung from two cables that pass through the two main towers and are fixed in concrete at each end. Each cable is made of 27,572 strands of wire. Construction began on January 5, 1933. The project cost more than $35 million.The Golden Gate Bridge construction project was carried out by the McClintic-Marshall Construction Co., founded by Howard H. McClintic and Charles D. Marshall, both of Lehigh university. Strauss remained head of the project, overseeing day-to-day construction and making some groundbreaking contributions. A graduate of the University of Cincinnati, he placed a brick from his alma mater's demolished McMicken Hall in the south anchorage before the concrete was poured. He innovated the use of movable safety netting beneath the construction site, which saved the lives of many otherwise-unprotected steelworkers pedestrians and bicyclists enjoy crossing the bridge as well as cars. That is why the bridge was built with walkways on either side of the six traffic lanes. At first, they were separated by the traffic lanes by only a metal curb, but railings between the walkways and the traffic lanes were added in 2003, primarily as a measure to prevent runaway cyclists from falling into the roadway. The main downside of the bridge has nothing to do with the construction, materials or economical effects of it, but mainly of the people who come to visit it., the golden gate bridge is a dangerous site because people who fall from it Intentionally or not have a 98% rate of dying. Most of these cases, except the fatal incidents during construction, are considered suicide attempts. More people die by suicide at the Golden Gate Bridge than at any other site in the world. The deck is approximately 245 feet (75 m) above the water. After a fall of approximately four seconds, jumpers hit the water at around 75 mph or approximately 120 km/h. Various methods have been proposed and implemented to reduce the number of suicides. The bridge is fitted with suicide hotlinetelephones, and staff patrol the bridge in carts, looking for people who appear to be planning to jump. Ironworkers on the bridge also volunteer their time to prevent suicides by talking or wrestling down suicidal people. The bridge is now closed to pedestrians at night.