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NATURAL
BRIDGES
The first bridges were built by nature itself. These are the result of erosion from river, sea or ice. |
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THE
FIRST HUMAN BRIDGES
The first bridges built by man were primitive, built of stone, timber, ropes or combinations of these materials. The earliest references of bridges built of human is a bridge over The Nile in year 2650 BC. |
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WOOD
BRIDGES
Probably was the first bridges built of timber. This material was normal easy to get and easy to work out. |
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STONE
BRIDGES
Human has used stone since the Stone Age, but after the Etruskers in eight century BC. learn to use the arch this became the most important bridge material up to the 19th century. |
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STEEL
BRIDGES
The first bridges with iron (Chains) was used in China before 600 A.D. In Europe came the first iron bridges as arch bridges of cast iron at the 18th century. In the beginning of 19th century, came bridges of wrought iron, and later steel bridges. Those materials did it possible to build stronger bridges, which could span over greater river and other obstructions. That came very important because the expansion of the railway in that time. |
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CONCRETE
BRIDGES
Cement has been discovered used back to 5600 BC. The Roman builds loot of bridges where they used a mortar to bind together the stone. The modern cement who is used in concrete to day was discovered 1824. The first reinforced concrete bridge was built in 1875. From then the concrete have been used more and more in bridges. |