Types+of+Bridges

Types of Bridges

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A suspension bridge is a type of many bridge types that is built for getting over obsticles like waterways and chasms by suspending a roadway from cables attatched to two major cable which runs along the length of the bridge. Suspension bridges are light weight and strong and more likely to survive a earthquake and extreme weather then most other bridges. Those arent the only things that can act on a bridge their are 3 other forces acting on a bridge; dead load, live load, and dynamic load. Dynamic load is simply what I said before earthquakes and extreme weather. Today there are many suspension bridges that help us get over obsticles, one of the most known suspension bridge in the Usa is the __Golden Gate bridge__ which connects San Francisco to the Marin county.====== There are 5 major types of suspension bridges; simple suspension bridge, under spanned suspension bridge, stress ribbon suspension bridge, suspended-deck suspension bridge, and the self anchored suspension bridge.
 * ===Simple suspension bridge:===

Simplest and oldest type of suspension bridge usually constructed as a foot bridge. In this type it has a flexible deck is provided which is supported by the cables anchored to the earth. The under spanned suspension bridge also known as the upper deck suspension bridge the main cables are below the deck of the bridge, The deck is raised on posts above the main cables, the cables that go vertical are anchored to the ground. The raised deck is less stable then any other suspension bridge. Not too many bridges are constructed this way because this type can be very unstable. This is a modfied form of a simple suspension bridge in which the deck lies on the main cables. They are very economical and require minimal materials to make. The deck is made out of a slender concrete that is in the shape of a catenary. They are design with one or more spans and are characterized by the flow of the smooth curves. You can build a stress ribbon bridge without putting pressure on the environment. By tension the cables and the deck between the abutments, the deck shares all the tension forces. The bridge as you can see in the picture above is a suspended deck suspension bridge this is supported by two towers that are anchored into the earth, the deck is attached to the main cables with the help of suspenders. This makes the type very suitable for heavy traffic and light weight rails. In this type of suspension bridge the main cables are attached to either ends of the deck and do not anchor into the earth. So, these bridges are often constructed in areas where the soil is unstable and anchoring the bridge is difficult. To actually build this type of bridge they will have to make a false design because the primary cables cannot be anchored until the bridge deck is completed. The bridge originated in the mid 19th century by an Australian engineer named Josef Langer in 1859. Its meant for cars, trucks, people, and light rail. Another beam bridge is a truss bridge. Truss is a bridge composed of connections elements typically straight which may be streesed from tension,compression os sometimes both in response to dynamic loads. A truss is a series of individual members.The individual members form a triangle pattern.truss bridge areone of the oldest types of large bridges in the United States. the first Truss bridge were built around 1820s truss bridges can be almost any size.In New Milford we have a truss bridge called Lover's Leap bridge.
 * **Under Spanned suspension bridge:**
 * **Stressed Ribbon suspension bridge:**
 * **Suspended-Deck suspension bridge:**
 * **Self Anchored suspension bridge**

Lover's Leap bridge was built in 1895

are the most simple of structure forms being supported by abutment at each end of the bridge.



The difference between a roman arch bridge and a through arch bridge is that the deck/load in a roman arch bridge is above the arch. The deck/load in a through arch bridge goes through the arch.