architecture Architecture is the art and technique of designing and building, as distinguished from the skills associated with construction. It is both the process and the product of sketching, conceiving, planning, designing, and constructing buildings ...

, a starling (or sterling) is a defensive bulwark, usually built with pilings or

brick A brick is a type of block used to build walls, pavements and other elements in masonry construction. Properly, the term ''brick'' denotes a block composed of dried clay, but is now also used informally to denote other chemically cured cons ...

s, surrounding the supports (or

pier Seaside pleasure pier in Brighton, England. The first seaside piers were built in England in the early 19th century.">England.html" ;"title="Brighton, England">Brighton, England. The first seaside piers were built in England in the early 19th ...

s) of a

bridge A bridge is a structure built to span a physical obstacle (such as a body of water, valley, road, or rail) without blocking the way underneath. It is constructed for the purpose of providing passage over the obstacle, which is usually someth ...

or similar construction. Starlings may be shaped to ease the flow of the water around the bridge, reducing the damage caused by

erosion Erosion is the action of surface processes (such as water flow or wind) that removes soil, rock, or dissolved material from one location on the Earth's crust, and then transports it to another location where it is deposited. Erosion is d ...

or collisions with flood-borne debris, and may also form an important part of the structure of the bridge, spreading the weight of the piers. The term cutwater is used for such a structure shaped with water flow in mind, as a pier or starling with a diamond point. A starkwater is a bulwark against ice floes. Depending on their shape and location, some starlings may accumulate river debris, mud and other objects, potentially creating navigational hazards or hindering downstream water flow.

Shape

Starlings may form part of a buttress for the vertical load of the bridge piers, and for that purpose would typically be symmetrical. Examples such as at the

Old Wye Bridge, Chepstow The Old Wye Bridge or Town Bridge at Chepstow, also known historically as Chepstow Bridge, crosses the River Wye between Monmouthshire in Wales and Gloucestershire in England, close to Chepstow Castle. Although there had been earlier wooden b ...

are on lower stretches of rivers which are tidal and that require a starling in both directions. Other starlings may be asymmetrical, so that the upstream aspect of a pier is larger as it a face sloping outwards, whilst downstream is vertical. The starling has a sharpened or curved extreme sometimes called the nose. The cutwater may be of concrete or masonry, but is often capped with a steel angle to resist abrasion and focus force at a single point to fracture floating pieces of ice striking the pier. In cold climates the starling is typically sloped at an angle of about 45° so current pushing against part-submerged ice flow tends to lift the solid ice, translating horizontal force of the current to a vertical force shearing the ice allowing the icy flows to pass on either side. A sloped, ice-cutting starling is known as a starkwater.

References

{{DEFAULTSORT:Starling (Architecture) Bridge components Hydraulic engineering

Shape

See also

References