There are five main types of bridges, these include the truss bridge, the arch bridge, the suspension, the beam bridge and the cable-stayed bridge. Each of these categories has various strengths, weaknesses and defining features and these are listed and clarified in the following report.
The Truss Bridge
Truss bridges are a reliable, economical and easy-to-build variety of bridges as they use a combination of tension and compression to provide a high level of stability. The effect of the high levels of tensile and compressive forces is that truss bridges are usually constructed from steel, reinforced concrete, timber and/or other high strength materials. The average span of a truss bridge is between 40 to 500 metres …show more content…
For example the towers are usually made from concrete, stone or metal as these materials are strong in compression.
An example of a stone-towered suspension bridge is the Brooklyn Bridge in New York, the United States of America.
The Beam Bridge:
The oldest form of bridges, beam bridges use a surprisingly complex method of pressure distribution which allows them to be effective, easy-to-build and economically beneficial bridges for short spans.
The average span of a beam bridge is between 15 to 180 metres and the tension forces at the bottom of a beam bridge limit the variety of materials a beam bridge can use. For example, a stone or concrete beam bridge would not be able to sustain the tension at the bottom of the beam as stone and concrete are only good in compression. On the other hand, wood or steel is a better choice for beam bridges as either of these materials can handle both types of force (compressive and tensile). However, if a stone or concrete beam bridge is constructed the bottom of the bridge is reinforced with steel rods or cables which allow the bridge to stretch in tension. An example of a concrete beam is the Bolsøy Bridge in Molde,