Dolphin (structure)
Encyclopedia
A dolphin is a man-made marine structure that extends above the water level and is not connected to shore.
Dolphins are usually installed to provide a fixed structure when it would be impractical to extend the shore to provide a dry access facility, for example, when ships (or the number of ships expected) are greater than the length of the berth/pier.
Typical uses include extending a berth
(a berthing dolphin) or providing a point to moor to (a mooring dolphin). Dolphins are also used to display regulatory information like speed limits etc, other information like advertising or directions and navigation information like a daybeacon as well as ranges and lighted aids to navigation.
Mooring dolphins can also be used to "cushion" ship impacts, somewhat similar to fender
s.
The structures typically consist of a number of piles
driven into the seabed or riverbed and connected together above the water level to provide a platform or fixing point. The piles can be untreated azobé
wood, pressure treated pine wood poles, or steel
or reinforced concrete
beams, blocks or tubes. Smaller dolphins can have the piles drawn together with wire rope, but larger dolphins would typically be fixed using a reinforced concrete
capping or a structural steel frame.
Access to a dolphin may be via a pedestrian bridge (mooring dolphins) but is usually by boat.
Dolphins are usually installed to provide a fixed structure when it would be impractical to extend the shore to provide a dry access facility, for example, when ships (or the number of ships expected) are greater than the length of the berth/pier.
Typical uses include extending a berth
Berth (moorings)
A berth is a location in a port or harbour used specifically for mooring vessels while not at sea.-Locations in a port:Berth is the term used in ports and harbors to define a specific location where a vessel may be berthed, usually for the purposes of loading and unloading.Most berths will be...
(a berthing dolphin) or providing a point to moor to (a mooring dolphin). Dolphins are also used to display regulatory information like speed limits etc, other information like advertising or directions and navigation information like a daybeacon as well as ranges and lighted aids to navigation.
Mooring dolphins can also be used to "cushion" ship impacts, somewhat similar to fender
Fender (boating)
In boating, a fender is a bumper used to absorb the kinetic energy of a berthing boat or vessel against a jetty, quay wall or other vessel. Fenders are used to prevent damage to boats, vessels and berthing structures. Fenders are nowadays constructed in several ways, typically of rubber, foam...
s.
The structures typically consist of a number of piles
Deep foundation
A deep foundation is a type of foundation distinguished from shallow foundations by the depth they are embedded into the ground. There are many reasons a geotechnical engineer would recommend a deep foundation over a shallow foundation, but some of the common reasons are very large design loads, a...
driven into the seabed or riverbed and connected together above the water level to provide a platform or fixing point. The piles can be untreated azobé
Lophira alata
Lophira alata is a species of plant in the Ochnaceae family. It is found in Cameroon, the Republic of the Congo, the Democratic Republic of the Congo, Ivory Coast, Equatorial Guinea, Gabon, Ghana, Liberia, Nigeria, Sierra Leone, Sudan, and Uganda. Its natural habitat is subtropical or tropical...
wood, pressure treated pine wood poles, or steel
Steel
Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...
or reinforced concrete
Reinforced concrete
Reinforced concrete is concrete in which reinforcement bars , reinforcement grids, plates or fibers have been incorporated to strengthen the concrete in tension. It was invented by French gardener Joseph Monier in 1849 and patented in 1867. The term Ferro Concrete refers only to concrete that is...
beams, blocks or tubes. Smaller dolphins can have the piles drawn together with wire rope, but larger dolphins would typically be fixed using a reinforced concrete
Reinforced concrete
Reinforced concrete is concrete in which reinforcement bars , reinforcement grids, plates or fibers have been incorporated to strengthen the concrete in tension. It was invented by French gardener Joseph Monier in 1849 and patented in 1867. The term Ferro Concrete refers only to concrete that is...
capping or a structural steel frame.
Access to a dolphin may be via a pedestrian bridge (mooring dolphins) but is usually by boat.