Civil Engineering Professional Engineer Practice Exam

What are arch bridges primarily used for?

1. Shorter spans

2. Movements of people only

3. Longer spans and movement of vehicles and water

4. Decoration in architecture

The correct answer is: Longer spans and movement of vehicles and water

Arch bridges are primarily designed to accommodate longer spans and facilitate the movement of vehicles and water. This design effectively distributes weight and forces, allowing them to support significant loads over greater distances compared to many other bridge types. The arch shape is inherently strong, as it converts vertical loads into horizontal forces that are then transferred to the supports or abutments. This capability makes arch bridges particularly suitable for crossing valleys, rivers, or any considerable gaps where long spans are essential. While the other choices may touch upon aspects of bridge utility, they do not capture the primary function of arch bridges as accurately. For instance, while shorter spans can be accommodated, arch bridges shine in situations requiring longer spans. Similarly, although they can serve pedestrian traffic or be aesthetically pleasing, their main purpose lies in enabling the passage of vehicles and water across significant distances effectively and safely.