Bridge

Arch bridges are one of the oldest types of bridges and have been around for thousands of years. Arch bridges have great natural strength.They were originally built of stone or brick but these days are built of reinforced concrete or steel. The introduction of these new materials allow arch bridges to be longer with lower spans.Instead of pushing straight down, the load of an arch bridge is carried outward along the curve of the arch to the supports at each end. The weight is transferred to the supports at either end.These supports, called the abutments, carry the load and keep the ends of the bridge from spreading out (I).

Very basic type of bridges that are supported by several beams of various shapes and sizes. They can be inclined or V shaped.

Truss bridges are one of the oldest types of modern bridges. Truss bridges are among a variety of bridge designs that are being used for road traffic. The basic shape of a truss bridge is like a right triangle, with the hypotenuse extending to the abutments.

Bridge with overhead cables supporting its roadway. One of the oldest of engineering forms, suspension bridges were constructed by primitive peoples using vines for cables and mounting the roadway directly on the cables.

The tower of a cable-stayed bridge is responsible for absorbing and dealing with compression forces. The cables attach to the roadway in various ways. Bridge that uses deck cables that are directly connected to one or more vertical columns.

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