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Coffer Dam
A cofferdam is an enclosure built within a body of water to allow the enclosed area to be pumped out. This pumping creates a dry working environment so that the work can be carried out safely. Cofferdams are commonly used for construction or repair of permanent dams, oil platforms, bridge piers, etc., built within water. These cofferdams are usually welded steel structures, with components consisting of sheet piles, wales, and cross braces. Such structures are usually dismantled after the construction work is completed. The origin of the word comes from ''coffer'' (originally from Latin ''cophinus'' meaning "basket") and ''dam'' from Proto-German ''*dammaz'' meaning "barrier across a stream of water to obstruct its flow and raise its level"). Uses For dam construction, two cofferdams are usually built, one upstream and one downstream of the proposed dam, after an alternative diversion tunnel or channel has been provided for the river flow to bypass the foundation area o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cofferdam Olmsted Locks Ohio River
A cofferdam is an enclosure built within a body of water to allow the enclosed area to be pumped out. This pumping creates a dry working environment so that the work can be carried out safely. Cofferdams are commonly used for construction or repair of permanent dams, oil platforms, bridge piers, etc., built within water. These cofferdams are usually welded steel structures, with components consisting of sheet piles, wales, and cross braces. Such structures are usually dismantled after the construction work is completed. The origin of the word comes from ''coffer'' (originally from Latin ''cophinus'' meaning "basket") and ''dam'' from Proto-German ''*dammaz'' meaning "barrier across a stream of water to obstruct its flow and raise its level"). Uses For dam construction, two cofferdams are usually built, one upstream and one downstream of the proposed dam, after an alternative diversion tunnel or channel has been provided for the river flow to bypass the foundation area of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caisson (engineering)
In geotechnical engineering, a caisson ( or ; borrowed from French ''caisson'', from Italian ''cassone'', meaning ''large box'', an augmentative of ''cassa'') is a watertight retaining structure used, for example, to work on the foundations of a bridge pier, for the construction of a concrete dam, or for the repair of ships. Caissons are constructed in such a way that the water can be pumped out, keeping the work environment dry. When piers are being built using an open caisson, and it is not practical to reach suitable soil, friction pilings may be driven to form a suitable sub-foundation. These piles are connected by a foundation pad upon which the column pier is erected. Caisson engineering has been used at least since the 18th century, and was notably used in the construction of the Brooklyn Bridge, which was completed in 1883. Types To install a caisson in place, it is brought down through soft mud until a suitable foundation material is encountered. While bedrock is pref ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dental Dam
A dental dam or rubber dam is a thin, square sheet, usually latex or nitrile, used in dentistry to isolate the operative site (one or more teeth) from the rest of the mouth. Sometimes termed "Kofferdam" (from German), it was designed in the United States in 1864 by . It is used mainly in endodontic, fixed prosthodontic (crowns, bridges) and general restorative treatments. Its purpose is both to prevent saliva interfering with the dental work (e.g. contamination of oral micro-organisms during root canal therapy, or to keep filling materials such as composite dry during placement and curing), and to prevent instruments and materials from being inhaled, swallowed or damaging the mouth. In dentistry, use of a rubber dam is sometimes referred to as ''isolation'' or ''moisture control''. Dental dams are also used for safer oral sex. Dentistry Background The technique used to apply the dental dam is selected according to the tooth requiring treatment. Several techniques can be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ballast Tank
A ballast tank is a compartment within a boat, ship or other floating structure that holds water, which is used as ballast to provide hydrostatic stability for a vessel, to reduce or control buoyancy, as in a submarine, to correct trim or list, to provide a more even load distribution along the hull to reduce structural hogging or sagging stresses, or to increase draft, as in a semi-submersible vessel or platform, or a SWATH, to improve seakeeping. Using water in a tank provides easier weight adjustment than the stone or iron ballast used in older vessels, and makes it easy for the crew to reduce a vessel's draft when it enters shallower water, by temporarily pumping out ballast. Airships use ballast tanks mainly to control buoyancy and correct trim. History The basic concept behind the ballast tank can be seen in many forms of aquatic life, such as the blowfish or argonaut octopus. The concept has been invented and reinvented many times by humans to serve a variety of purpo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deck (ship)
A deck is a permanent covering over a compartment or a hull of a ship. On a boat or ship, the primary or upper deck is the horizontal structure that forms the "roof" of the hull, strengthening it and serving as the primary working surface. Vessels often have more than one level both within the hull and in the superstructure above the primary deck, similar to the floors of a multi-storey building, that are also referred to as decks, as are certain compartments and decks built over specific areas of the superstructure. Decks for some purposes have specific names. Structure The main purpose of the upper or primary deck is structural, and only secondarily to provide weather-tightness and support people and equipment. The deck serves as the lid to the complex box girder which can be identified as the hull. It resists tension, compression, and racking forces. The deck's scantling is usually the same as the topsides, or might be heavier if the deck is expected to carry heavier loads ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bulkhead (partition)
A bulkhead is an upright wall within the hull of a ship or within the fuselage of an airplane. Other kinds of partition elements within a ship are decks and deckheads. Etymology The word ''bulki'' meant "cargo" in Old Norse. During the 15th century sailors and builders in Europe realized that walls within a vessel would prevent cargo from shifting during passage. In shipbuilding, any vertical panel was called a head. So walls installed abeam (side-to-side) in a vessel's hull were called "bulkheads". Now, the term bulkhead applies to every vertical panel aboard a ship, except for the hull itself. History Bulkhead partitions are considered to have been a feature of Chinese junks, a type of ship. Song Dynasty author Zhu Yu (fl. 12th century) wrote in his book of 1119 that the hulls of Chinese ships had a bulkhead build. The 5th-century book ''Garden of Strange Things'' by Liu Jingshu mentioned that a ship could allow water to enter the bottom without sinking. Archaeolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cofferdam TT A356
A cofferdam is an enclosure built within a body of water to allow the enclosed area to be pumped out. This pumping creates a dry working environment so that the work can be carried out safely. Cofferdams are commonly used for construction or repair of permanent dams, oil platforms, bridge piers, etc., built within water. These cofferdams are usually welded steel structures, with components consisting of sheet piles, wales, and cross braces. Such structures are usually dismantled after the construction work is completed. The origin of the word comes from ''coffer'' (originally from Latin ''cophinus'' meaning "basket") and ''dam'' from Proto-German ''*dammaz'' meaning "barrier across a stream of water to obstruct its flow and raise its level"). Uses For dam construction, two cofferdams are usually built, one upstream and one downstream of the proposed dam, after an alternative diversion tunnel or channel has been provided for the river flow to bypass the foundation area of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stony Island (Michigan)
250px, View of Stony Island from Grosse Ile Stony Island is an island in the Detroit River, in southeast Michigan. It has been used for hunting and fishing as long as humans have inhabited the region; from the mid-19th century to the mid-20th century, it was the site of a small settlement and served as a central location for the construction of the Livingstone Channel, as well as various civil engineering projects involving the Detroit River. By the 1990s, it had become completely uninhabited; it is now open to the public and administered by the Michigan Department of Natural Resources. Geography Stony Island's coordinates are and it is contained within Grosse Ile Township, in Wayne County. In the Detroit River, it is downstream of Lake St. Clair and upstream of Lake Erie. Immediately to its west is the much-larger Grosse Ile, which is approximately away; it was once connected to Grosse Ile by a railroad bridge, which was demolished by 1912. Past Grosse Ile is Trenton, Mi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deepwater Horizon Oil Spill
The ''Deepwater Horizon'' oil spill (also referred to as the "BP oil spill") was an industrial disaster that began on 20 April 2010 off of the coast of the United States in the Gulf of Mexico on the BP-operated Macondo Prospect, considered to be the largest marine oil spill in the history of the petroleum industry and estimated to be 8 to 31 percent larger in volume than the previous largest, the Ixtoc I oil spill, also in the Gulf of Mexico. The United States federal government estimated the total discharge at . After several failed efforts to contain the flow, the well was declared sealed on 19 September 2010. Reports in early 2012 indicated that the well site was still leaking. The ''Deepwater Horizon'' oil spill is regarded as one of the largest environmental disasters in world history. A massive response ensued to protect beaches, wetlands and estuaries from the spreading oil utilizing skimmer ships, floating booms, controlled burns and of oil dispersant. Due to t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hull (watercraft)
A hull is the watertight body of a ship, boat, or flying boat. The hull may open at the top (such as a dinghy), or it may be fully or partially covered with a deck. Atop the deck may be a deckhouse and other superstructures, such as a funnel, derrick, or mast. The line where the hull meets the water surface is called the waterline. General features There is a wide variety of hull types that are chosen for suitability for different usages, the hull shape being dependent upon the needs of the design. Shapes range from a nearly perfect box in the case of scow barges to a needle-sharp surface of revolution in the case of a racing multihull sailboat. The shape is chosen to strike a balance between cost, hydrostatic considerations (accommodation, load carrying, and stability), hydrodynamics (speed, power requirements, and motion and behavior in a seaway) and special considerations for the ship's role, such as the rounded bow of an icebreaker or the flat bottom of a landing craft. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dam Coffer
A dam is a barrier that stops or restricts the flow of surface water or underground streams. Reservoirs created by dams not only suppress floods but also provide water for activities such as irrigation, human consumption, industrial use, aquaculture, and navigability. Hydropower is often used in conjunction with dams to generate electricity. A dam can also be used to collect or store water which can be evenly distributed between locations. Dams generally serve the primary purpose of retaining water, while other structures such as floodgates or levees (also known as dikes) are used to manage or prevent water flow into specific land regions. The earliest known dam is the Jawa Dam in Jordan, dating to 3,000 BC. The word ''dam'' can be traced back to Middle English, and before that, from Middle Dutch, as seen in the names of many old cities, such as Amsterdam and Rotterdam. History Ancient dams Early dam building took place in Mesopotamia and the Middle East. Dams were us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drydock
A dry dock (sometimes drydock or dry-dock) is a narrow basin or vessel that can be flooded to allow a load to be floated in, then drained to allow that load to come to rest on a dry platform. Dry docks are used for the construction, maintenance, and repair of ships, boats, and other watercraft. History Greco-Roman world The Greek author Athenaeus of Naucratis (V 204c-d) reports something that may have been a dry dock in Ptolemaic Egypt in the reign of Ptolemy IV Philopator (221-204 BC) on the occasion of the launch of the enormous ''Tessarakonteres'' rowing ship. It has been calculated that a dock for a vessel of such a size might have had a volume of 750,000 gallons of water. In Roman times, a shipyard at Narni, which is still studied, may have served as a dry dock. Medieval China The use of dry docks in China goes at least as far back the 10th century A.D. In 1088, Song Dynasty scientist and statesman Shen Kuo (1031–1095) wrote in his '' Dream Pool Essays'': Renais ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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