Suspension bridges have been around for hundreds of years. The suspension bridge is used for its functionality and aesthetic appeal. Some of the most recognizable bridges such as the Golden Gate Bridge and the Brooklyn Bridge are examples of suspension bridges. Over the years, the design and technology that is used to make suspension bridges has improved tremendously.
Simple Suspension Bridges
Simple suspension bridges are the longest-running type of suspension bridge there is. There is evidence that the ancient Incas used suspension bridges for livestock and farming purposes. Simple suspension bridges are suspended between two high locations. The surface of the bridge is held up by cables and ropes. The main characteristic of simple suspension bridges is the downward arc that the surface must have in order for it to support the weight of people and livestock. While these types of bridges can support low-weight traffic, they would not be sufficient for modern automobiles or trains.
Modern Suspension Bridges
The modern suspension bridge has been around since the late 19th century. The deck of the modern suspension bridge is hung below suspension cables that are held up by vertical supports. The vertical supports are often designed with aesthetics in mind and is usually fashioned after some type of tower. These towers anchor the suspension cables. The large horizontal cables are further supported by smaller vertical suspender cables that run the length of the bridge. The main factors that allow suspension bridges to work are tension and compression. The tension is created by the vertical suspender cables, and the towers compress the weight that is being transferred downward.
The design of modern suspension bridges allows them to cover longer distances than other types of bridges. Suspension bridges also provide a remarkable amount of support for the amount of material that is need to construct them. Suspension bridges are much cheaper to build for this reason, which makes them very attractive. The way in which suspension bridges are constructed allows boat traffic to continue, which is not possible when constructing other types of bridges.