Bridge+Use+and+Application

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= Climate Conditions = There are many types of bridges for many different types of of reasons. One of the reasons is for climate changes. In the world there are many natural disasters that strike and destroy cities, towns, and sometimes even states. But some bridges, like suspension bridges, are strong enough to withstand most natural disasters. The early bridges made of stone were easily knocked down by high speed winds, but most modern bridge now can withstand storms. In the 1800's bridge makers thought about new ways of making bridges, so they made a suspension bridge from steel and concrete. This bridge is specifically made to undergo fire, hurricanes and flooding without being destroyed.

= Material use = Where bridges are being built is crucial to what kind of materials that have to be used. Timber or concrete piles can support light bridges, and for a heavier bridge, concrete or masonry supports would be used. From about 1100 the most common bridges were built using stone masonry. When hard stone was used as foundation on firm ground the bridges made still stand today. Not only are these stone bridges extremly durable but they can also be made very beautiful in their past. Unfortunatly these bridges have been known to be very expensive. Some stones they used are granite, gneiss, porphyry, diabis, and crystallized limestone.But earlier in history, the Mayans built their bridges using stone, wood, and vines. By the 1800's, U.S. builders started to make bridges out of steel, which is lightweight and strong.

Above: Diagram of Mayan Bridge

Geographic Conditions: Span and Topography Notes There are many important steps to building a bridge, including the geographical conditions of bridges. Engineers usually build bridges in wide or narrow canyons where there's enough space to build a bridge. They also make sure that the landscape doesn't have many earthquakes. Can you imagine yourself on a bridge, and it starts to collapse because the bridge makers used the wrong material? Well the engineers check what kind of climate they are in to decide what kind of materials they will use during construction.

(collapsed bridge due to a tropical storm)