A dolphin is a group of pilings arrayed together to serve variously as a protective hardpoint along a dock, in a waterway, or along a shore; as a means or point of stabilization of a dock, bridge, or similar structure; as a mooring point; and as a base for navigational aids.
Dolphins typically consist of a number of piles driven into the seabed or riverbed, and connected above the water level to provide a platform or fixing point. The piles can be untreated or pressure-treated timber piles, or steel or reinforced concrete piles. Smaller dolphins can have the piles drawn together with wire rope, but larger dolphins are typically fixed using a reinforced concrete capping or a structural steel frame.
Access to a dolphin may be via a pedestrian bridge, particularly in the case of mooring dolphins, but is often 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 the number of ships is greater than can be accommodated by the length of the berth/pier. [1] Typical uses include extending a berth (a berthing dolphin) or providing a mooring point (a mooring dolphin).
Dolphins are also used to protect structures from possible impact by ships, in a similar fashion to fenders. [2] A notable example of dolphins used to protect a bridge is the Sunshine Skyway Bridge across the mouth of Tampa Bay. In 1980, the MV Summit Venture hit a pier on one of the bridge's two, two-lane spans causing a 1,200-foot (370 m) section of the bridge to fall into the water, resulting in 35 deaths. When a replacement span was designed, a top priority was to prevent ships from colliding with the new bridge. [3] The new bridge is protected by 36 dolphins: four large dolphins protecting the two main pylons supporting the cable-stayed main span plus 32 smaller dolphins protecting bridge piers for 1⁄4 mile (400 m) to either side of the main span. [3] The cost of the dolphins was $41 million (equivalent to $94 million in 2023 dollars). [3]
Dolphins are also used to house navigation aids such as lights or daybeacons, and display regulatory information such as speed limits and other safety information, or even advertising.
The Confederation Bridge is a box girder bridge carrying the Trans-Canada Highway across the Abegweit Passage of the Northumberland Strait, linking the province of Prince Edward Island with the mainland province of New Brunswick. Opened May 31, 1997, the 12.9-kilometre (8.0 mi) bridge is Canada's longest bridge and the world's longest bridge over ice-covered water.
A mooring is any permanent structure to which a seaborne vessel may be secured. Examples include quays, wharfs, jetties, piers, anchor buoys, and mooring buoys. A ship is secured to a mooring to forestall free movement of the ship on the water. An anchor mooring fixes a vessel's position relative to a point on the bottom of a waterway without connecting the vessel to shore. As a verb, mooring refers to the act of attaching a vessel to a mooring.
A pier is a raised structure that rises above a body of water and usually juts out from its shore, typically supported by piles or pillars, and provides above-water access to offshore areas. Frequent pier uses include fishing, boat docking and access for both passengers and cargo, and oceanside recreation. Bridges, buildings, and walkways may all be supported by architectural piers. Their open structure allows tides and currents to flow relatively unhindered, whereas the more solid foundations of a quay or the closely spaced piles of a wharf can act as a breakwater, and are consequently more liable to silting. Piers can range in size and complexity from a simple lightweight wooden structure to major structures extended over 1,600 m (5,200 ft). In American English, a pier may be synonymous with a dock.
The Tasman Bridge is a prestressed concrete girder bridge connecting the Tasman Highway over the River Derwent in Hobart, Tasmania, Australia. When it opened on 29 March 1965, the Tasman was the longest prestressed concrete bridge in Australia, with a total length measuring 1,396 metres (4,580 ft), including approaches. The bridge provides a vital link between Hobart's city centre on the western shore and the City of Clarence on the eastern shore. Averaging 73,029 vehicle crossings per day, the bridge is the highest volume road section in Tasmania. It features five lanes of traffic including a central lane equipped for tidal flow operations and separated shared-use walkways on both sides, with ramp upgrades for improved access and cyclists completed in 2010.
Nakagusuku Bay is a bay on the southern coast of Okinawa Island on the Pacific Ocean in Japan. The bay covers 220 square kilometres (85 sq mi) and ranges between 10 metres (33 ft) to 15 metres (49 ft) deep. The bay is surrounded by the municipalities of Uruma, Kitanakagusuku, Nakagusuku, Nishihara, Yonabaru, Nanjō, all in Okinawa Prefecture. In 1852, while visiting the Ryukyu Kingdom, Commodore Matthew Perry mapped Okinawa and labeled Nakagusuku Bay as "Perry's Bay". During the final months of World War II, the bay became a U.S. Navy forward base and was nicknamed "Buckner Bay".
The word dock in American English refers to one or a group of human-made structures that are involved in the handling of boats or ships. In British English, the term is not used the same way as in American English, it is used to mean the area of water that is next to or around a wharf or quay. The exact meaning varies among different variants of the English language.
A girder bridge is a bridge that uses girders as the means of supporting its deck. The two most common types of modern steel girder bridges are plate and box.
A linkspan or link-span is a type of drawbridge used mainly in the operation of moving vehicles on and off a roll-on/roll-off (RO-RO) vessel or ferry, particularly to allow for tidal changes in water level.
In boating, a fender is an air-filled ball or a device in other shape and material used to absorb the kinetic energy of a boat or vessel berthing against a jetty, quay wall or other vessel. Fenders, used on all types of vessels, from cargo ships to cruise ships, ferries and personal yachts, prevent damage to vessels and berthing structures. To do this, fenders have high energy absorption and low reaction force. Fenders are typically manufactured out of rubber, foam elastomer or plastic. Rubber fenders are either extruded or made in a mold. The type of fender that is most suitable for an application depends on many variables, including dimensions and displacement of the vessel, maximum allowable stand-off, berthing structure, tidal variations and other berth-specific conditions. The size of the fender unit is based on the berthing energy of the vessel which is related to the square of the berthing velocity.
The Spit Bridge, a steel and concrete girder bridge with a bascule lift span across the Middle Harbour, is located 10 kilometres (6.2 mi) north-east of the central business district in Sydney, Australia. The bridge carries The Spit Road (A8) from a point called The Spit, and connects the suburbs of Mosman, on the south bank and Seaforth, on the north bank.
A deep foundation is a type of foundation that transfers building loads to the earth farther down from the surface than a shallow foundation does to a subsurface layer or a range of depths. A pile or piling is a vertical structural element of a deep foundation, driven or drilled deep into the ground at the building site.
LNG Hrvatska d.o.o. is a company that operates a floating liquefied natural gas (LNG) regasification terminal in Omišalj on the island of Krk, Croatia. It commenced operations on 1 January 2021, with full capacity booked for the next three years.
A berth is a designated location in a port or harbour used for mooring vessels when they are not at sea. Berths provide a vertical front which allows safe and secure mooring that can then facilitate the unloading or loading of cargo or people from vessels.
Floats are airtight hollow structures, similar to pressure vessels, designed to provide buoyancy in water. Their principal applications are in watercraft hulls, aircraft floats, floating piers, pontoon rhinos, pontoon causeways, and marine engineering applications such as salvage.
A Rigid-frame bridge is a bridge in which the superstructure and substructure are rigidly connected to act as a continuous unit. Typically, the structure is cast monolithically, making the structure continuous from deck to foundation. The connections between members are rigid connections which transfer bending moment, axial forces, and shear forces. A bridge design consisting of a rigid frame can provide significant structural benefits, but can also be difficult to design and/or construct.
Clarence Stanley Coe was an American master bridge builder and railroad civil engineer, who supervised the planning and building of the Florida East Coast Railway's Seven Mile Bridge, linking the Florida Keys to Marathon, Monroe County, which, when completed in January 1912, was acclaimed as the longest bridge in the world and an engineering marvel. Later, Coe was appointed the first city manager of Miami, Florida, and after that was appointed chief engineer of Duval County, Florida.
The Samuel De Champlain Bridge, colloquially known as the Champlain Bridge, is a cable-stayed bridge design by architect Poul Ove Jensen and built to replace the original Champlain Bridge over the Saint Lawrence River in Quebec, between Nuns' Island in the borough of Verdun in Montreal and the suburban city of Brossard on the South Shore. A second, connected bridge links Nuns' Island to the main Island of Montreal. The bridge is the busiest bridge in the country with more cars flowing into it than any other bridge.
The Hay Bridge is a road bridge that carries the Cobb Highway across the Murrumbidgee River at Hay, New South Wales, Australia. The current bridge is the second bridge located in Hay that crosses the Murrumbidgee; the first bridge was in operation from 1873 until 1973; the second and current bridge has operated since 1973.
Marine construction is the process of building structures in or adjacent to large bodies of water, usually the sea. These structures can be built for a variety of purposes, including transportation, energy production, and recreation. Marine construction can involve the use of a variety of building materials, predominantly steel and concrete. Some examples of marine structures include ships, offshore platforms, moorings, pipelines, cables, wharves, bridges, tunnels, breakwaters and docks. Marine construction may require diving work, but professional diving is expensive and dangerous, and may involve relatively high risk, and the types of tools and equipment that can both function underwater and be safely used by divers are limited. Remotely operated underwater vehicles (ROVs) and other types of submersible equipment are a lower risk alternative, but they are also expensive and limited in applications, so when reasonably practicable, most underwater construction involves either removing the water from the building site by dewatering behind a cofferdam or inside a caisson, or prefabrication of structural units off-site with mainly assembly and installation done on-site.
Bridge protection systems prevent ship collision damage to a bridge by either deflecting an aberrant ship from striking the piers of a bridge, or sustaining and absorbing the impact.