A truss bridge is a bridge whose load-bearing superstructure is composed of a truss, a structure of connected elements, usually forming triangular units. The connected elements, typically straight, may be stressed from tension, compression, or sometimes both in response to dynamic loads. There are several types of truss bridges, including some with simple designs that were among the first bridges designed in the 19th and early 20th centuries. A truss bridge is economical to construct primarily because it uses materials efficiently.
A truss bridge operated by Southern Pacific Railroad in Contra Costa County, California converted to pedestrian use and pipeline support
Pratt through truss of the former Seaboard Air Line Railway, located near Willow, Florida; abandoned since the mid-1980s
Deck truss railroad bridge over the Erie Canal in Lockport, New York
The four span through truss General Hertzog Bridge over the Orange River at Aliwal North carries vehicular traffic
A bridge is a structure built to span a physical obstacle without blocking the way underneath. It is constructed for the purpose of providing passage over the obstacle, which is usually something that is otherwise difficult or impossible to cross. There are many different designs of bridges, each serving a particular purpose and applicable to different situations. Designs of bridges vary depending on factors such as the function of the bridge, the nature of the terrain where the bridge is constructed and anchored, the material used to make it, and the funds available to build it.
A temporary wooden footbridge leading to Luang Prabang in Laos
The covered bridge in West Montrose, Ontario, Canada
The Albertus L. Meyers Bridge in Allentown, Pennsylvania, U.S., "one of the earliest surviving examples of monumental, reinforced concrete construction," according to the American Society of Civil Engineers.
Mohammed VI Bridge in Morocco