Arch Bridge

a bridge with span structures, the basic components of which are arches or vaults. Characteristic traits of an arch bridge are the transfer to the supports not only of the vertical but also the horizontal stresses (thrust), as well as the strain, primarily of compression, on the arches or vaults. Stone arch bridges have been known since the most ancient times. Modern arch bridges are built, for the most part, of reinforced concrete or of steel. An example is the railroad arch bridge across the Oka River at the city of Gorky. It was built of precast reinforced concrete and has main spans of 150 m each. In special instances thrustless arch bridges have been erected using special elements (tie beams) which take the thrust. Arch bridges are usually built with a roadway on top. They are marked by lightness of structural components and architectural expressiveness.