Viaduct
The 1812 Laigh Milton Viaduct in Ayrshire – the oldest surviving railway bridge in Scotland | |
| Ancestor | Trestle bridge, box girder bridge |
|---|---|
| Related | Aqueduct |
| Descendant | None |
| Carries | Expressways, highways, streets, railways |
| Span range | Short (multiple) |
| Material | reinforced concrete, prestressed concrete, masonry |
| Movable | No |
| Design effort | medium |
| Falsework required | available for use, since viaducts are all composed of low bridges. |
A viaduct is a specific type of bridge that consists of a series of arches, piers or columns supporting a long elevated railway or road. Typically a viaduct connects two points of roughly equal elevation, allowing direct overpass across a wide valley, road, river, or other low-lying terrain features and obstacles. The term viaduct is derived from the Latin via meaning "road", and ducere meaning "to lead". It is a 19th-century derivation from an analogy with ancient Roman aqueducts. Like the Roman aqueducts, many early viaducts comprised a series of arches of roughly equal length.