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Bridges. BY: Kari Wagner Ashley Vonada & Elizabeth Rossbach. Historical Facts. The first Bridges were simple. Hunters would drag a fallen tree across a stream to walk across. Some would tie branches or logs together to make a wider path. Roman Bridges: 1 st & 2 nd century AD.
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Bridges BY: Kari Wagner Ashley Vonada & Elizabeth Rossbach
Historical Facts • The first Bridges were simple. • Hunters would drag a fallen tree across a stream to walk across. • Some would tie branches or logs together to make a wider path.
Roman Bridges: 1st & 2nd century AD • They built bridges over ravines. • They eventually built bridges over rivers with no land or rock underneath. • These bridges were made possible with their invention of concrete.
Inhabited Bridges: 12th-16th Century AD • The most famous types of bridges during this time were ones with houses on them. • France was known to have about thirty- five of these bridges. • The most famous and longest lasting of these bridges was the London Bridge.
Ironbridge: AD 1779 • Within a few months the worlds first ironbridge was built. • It weighed about 378 tons 10cwt.
Types of Bridges One type of bridge is the Girder Bridge. The Girder Bridge is the most common and basic form of bridges.
Types of Bridges [Cont.] • The next type of bridge is the Arch Bridge. • Arch bridges after girder bridges are the oldest type of bridge. • Many Arch bridges are suited to use on stone and over valleys.
Types of Bridges [Cont.] • Another type of bridge is the Truss bridge. • Trusses are also simple bridges that for the most part are straight.
Types of Bridges [Cont.] • The next type of bridge is the Cable Stayed bridge. • Basic cable bridges are a single girder with one or more towers with cables to support the girder.
Types of Bridges [Cont.] • The last type of bridge is the Rigid Frame bridge. • In the rigid frame bridge the girders and the piers are a single structure.