Difference Between Bridge And Culvert
Imagine life without bridges. Even the smallest river would be a barrier to travel and trade. To cross a broad river we would have to wade across or wait for a ferry boat. To cross a steep canyon would require trudging down one side and climbing slowly up the other. Before bridges were built, cars and trains lined up at busy crossings, waiting for traffic going in other directions.
There are more than 500,000 bridges in the United States today. Most of them are designed to carry automobile or railroad traffic, but some are intended for pedestrians only. Without bridges we would not have a modern system of highways and railroads. Most bridges are so short that they do not have names, and most travelers do not even notice going over them. There are some bridges, however, that are famous for their length, for their outstanding design, and for their beauty.
Culvert, a drainage structure for carrying water beneath a barrier, such as a highway or railway embankment. The drainage structure may be rectangular, circular, or semicircular in cross section. A rectangular culvert, used for openings greater than 12 square feet (1.1 sq meters), is usually made of reinforced concrete. A circular culvert is used for openings from 1 to 10 feet (0.3 to 3 meters) in diameter. The smaller circular culverts are commonly made of corrugated metal, concrete, or vitrified clay, and the larger ones of corrugated metal or reinforced concrete. A semicircular culvert, or arch culvert, used for spans up to 20 feet (6.1 meters), is usually made of corrugated metal, which has largely replaced masonry construction for this type of culvert. In the larger sizes the arch is formed by bolting together preshaped sections of the metal. The base of the arch rests on concrete.