Five Types of Bridges

Suspension Bridge

Engineers design suspension bridges to span great distances over water and land. Span length ranging from 2,000 to 7,000 feet make the suspension bridge the most expensive to build. A bridge is categorized as suspension because huge main cables suspends the roadway. These cables rest on top of tall towers and are secured on land at each end by anchorages.

Cable-Stayed Bridge

Cable-Stay Bridges are used for medium length bridges because they do not require large anchorage. Cable-Stay Bridges have roadways that are suspended from cables just like a suspension bridge. However, in a cable-stay bridge the cables are connected to the towers and the tower alone take the load of the bridge. Designers can attach the cables in different patterns to the roadway creating an impressive structure.

Cantilever Bridge

Cantilever Bridges are stiffer than suspension bridges and are able to carry heavier traffic like railroad trains. In a cantilever bridge two beams are project from opposite sides. Cantilever Bridges are sort of like a swimming pool diving board. At one end the bridge is anchored and at the other end it is cantilevered. When the two cantilever beams meet they are connected forming a rigid continuous beam.

Beam or Girder Bridge

Girder Bridges are the simplest and most basic bridge. A horizontal beam carring the roadway is supported at each end by piers. The load of traffic on the beam as well as the beam's weight and roadway pushes directly down on the piers. Girder Bridges are used typically in bridge overpasses and bridge walkways.

Arch Bridge

Arch Bridges are used in bridge overpasses and walkways just like the girder bridge. The Arch Bridge is a natural looking brige complementing Natures environment. Load weight from the traffic and roadway is transferred outward along the cruves of the arch to the end supports called abutments.

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