Bridges designed for modern infrastructure will usually be constructed of steel or reinforced concrete, or a combination of both.

Since no moments are transferred, thrust (as from an arch bridge) cannot be accommodated, leading to innovative designs, such as lenticular trusses and bow string arches, which contain the horizontal forces within the superstructure.

Some viaducts such as the Feiyunjiang Bridge in China have multiple simply supported spans held up by piers.

As a result, beam bridges rarely span more than 250 feet (80 m).

This does not mean that beam bridges are not used to cross great distances; it only means that a series of beam bridges must be joined together, creating what is known as a continuous span.