Arch Bridges

Advantages:

• Good for short spans;
• Inexpensive, with local building materials such as stone and brick, being used in the past. Today, concrete is more likely to be used.
• Wider distances can be spanned by building more arches.

Disadvantages:

• Uses a lot of material, even on short spans.

This is the pack horse bridge at Wycollar, Lancashire, built from local stone. Notice how narrow it is, and how low are the sides. It was designed for use by horses with their load carried on either side of a saddle. Bridges using arches were built as long ago as 3200 B.C. by the Sumerians. It was the Romans who introduced arch bridges to Britain. Until the late 17th century, arch bridge construction in Britain was based on a full semi-circle. When Parliament allowed turnpike roads to be constructed, improvements in design began to appear. Basing an arch on a segment of a circle allowed a greater span. Railway builders made great use of arches, often linking many together to form a long viaducts.

Bridge index.

Forces in bridges.