Cons of Suspension Bridges

A suspension bridges is one in which the road hangs from cables. The main cables are pulled across and connected to towers along the span of the bridge. More cables hang down vertically from the main cables and connect to the road. The main cables extend from the towers and are anchored to the ground. Simple suspension bridges date back to 600 AD; suspension bridges have gotten more complex and safer as the years have passed. They can span longer distances, but they can be dangerous if not built correctly.

Wind

Wind is one of the main dangers with suspension bridges. These bridges are built to move, and high wind can cause damage. If the road moves such that too much weight is put on the support cables, they can break. Engineers must account for this and add extra support where needed to stabilize the road.

Lightness

Suspension bridges are built light, with little support underneath the road. A bridge built too heavy can't be held up by the cables. So they cannot support heavy loads of traffic in concentrated areas.

Time and Cost

Suspension bridges take a lot of time and cost a lot to build. The materials needed are not costly, but builders use a lot of labor hours. The complicated engineering required to build a bridge for a specific location and make sure it is safe from the local elements can also hold up construction and add to the costs of the project.

Access

Building a suspension bridge may mean water access will be closed during construction. Road sections must be raised from below and put in place, so the waterway below might be closed from time to time to pull the sections up and into the place. If the waterway carries a lot of boat traffic, it can cause traffic problems or citizen complaints.

Flexibility

Flexibility keeps some types of traffic from using suspension bridges. The bridges are built to move with the wind enough that they do not break. Even with extra support, this movement cannot be eliminated because of the cable system. Because of this flexibility, railroads cannot use suspension bridges because rails need a stiff road. Rail traffic also carries heavy freight that by the suspension bridge may not be able to hold.