Strength -

Strength -

Strength -

A beam bridge's strength depends on the strength of the roadway and can be increased by adding additional piers.

An arch bridge is a bridge with abutments at each end shaped as a curved arch

Suspension bridges in their simplest form were originally made from rope and wood.

weakness

weakness

weakness

Suspension bridges are flexible, which is an advantage until conditions become severe. Instability in extremely turbulent conditions or during strong earthquakes may require temporary closure. In 1940, high winds caused the Tacoma Narrows bridge, near Seattle, Washington, to collapse.

Beam bridges may be costly even for rather short spans, since expensive steel is required as a construction material.

The longest of this type of bridge in the world is the one found in China, specifically over the Yangtze River spanning over 1,800 feet.