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Lifting Bridge
A bascule bridge (also referred to as a drawbridge or a lifting bridge) is a moveable bridge with a counterweight that continuously balances a span, or leaf, throughout its upward swing to provide clearance for boat traffic. It may be single- or double-leafed. The name comes from the French term for balance scale, which employs the same principle. Bascule bridges are the most common type of movable span because they open quickly and require relatively little energy to operate, while providing the possibility for unlimited vertical clearance for marine traffic. History Bascule bridges have been in use since ancient times, but until the adoption of steam power in the 1850s, very long, heavy spans could not be moved quickly enough for practical application. Types There are three types of bascule bridge and the counterweights to the span may be located above or below the bridge deck. The fixed-trunnion (sometimes a "Chicago" bascule) rotates around a large axle that raises the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lift Bridge
A vertical-lift bridge or just lift bridge is a type of movable bridge in which a span rises vertically while remaining parallel with the deck. The vertical lift offers several benefits over other movable bridges such as the bascule and swing-span bridges. Generally speaking, they cost less to build for longer moveable spans. The counterweights in a vertical lift are only required to be equal to the weight of the deck, whereas bascule bridge counterweights must weigh several times as much as the span being lifted. As a result, heavier materials can be used in the deck, and so this type of bridge is especially suited for heavy railroad use. The biggest disadvantage to the vertical-lift bridge (in comparison with many other designs) is the height restriction for vessels passing under it, due to the deck remaining suspended above the passageway. Although most vertical-lift bridges use towers, each equipped with counterweights, some use hydraulic jacks located below the deck ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Donald Scherzer
William Donald Scherzer (January 27, 1858 – July 20, 1893) was an American engineer and inventor who invented the rolling lift bridge. Early life Scherzer's parents were William and Wilhelmina Scherzer, who immigrated from Germany in 1847. Scherzer was born in Peru, Illinois on January 27, 1858 as the second son in a family of three sons and one daughter. Mid-life Scherzer received his primary education in public schools. He exhibited talent in art and mathematics, where his father had exhibited talent in music and art. After elementary school Scherzer entered the private schooling of Professor Eggers at the age of 15 for college prep courses. He later then took up civil engineering at the Polytechnicum college in Zurich, Switzerland when he was eighteen years old. There he was at the top of his class. Scherzer was considered a competitor both in play and studies by all that knew him closely. He graduated from the Zurich engineering college in 1880. Career Scherz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moveable Bridge
A moveable bridge, or movable bridge, is a bridge that moves to allow passage for boats or barges. In American English, the term is synonymous with , and the latter is the common term, but drawbridge can be limited to the narrower, historical definition used in some other forms of English, in which ''drawbridge'' refers to only a specific type of moveable bridge often found in castles . An advantage of making bridges moveable is the lower cost, due to the absence of high piers and long approaches. The principal disadvantage is that the traffic on the bridge must be halted when it is opened for passage of traffic on the waterway. For seldom-used railroad bridges over busy channels, the bridge may be left open and then closed for train passages. For small bridges, bridge movement may be enabled without the need for an engine. Some bridges are operated by the users, especially those with a boat, others by a bridgeman (or bridge tender); a few are remotely controlled using video-ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Bascule Bridges
A list of bascule bridges by country: Australia * Birkenhead Bridge carries traffic across the Port River at Port Adelaide * Tom 'Diver' Derrick Bridge - Port Adelaide, South Australia, single leaf road bascule * Mary MacKillop Bridge - Port Adelaide, South Australia, single leaf rail bascule * Batemans Bay Bridge, Batemans Bay, New South Wales, over the Clyde River * Spit Bridge - Sydney * Grafton Bridge (New South Wales) - Grafton, New South Wales rail lower deck, road upper deck - lift span out of use * Narooma Bridge - Narooma, still in use in 2005 * Carrathool Bridge - Carrathool, New South Wales, across the Murrumbidgee River - the last surviving example of a particular type of bascule lift span * Broadwater Bridge, across the Richmond River - built using the renovated bascule span from the demolished Barneys Point Bridge on the Tweed River (New South Wales), converted from counterweight to hydraulic ram lift. * Bridge on Franklin Wharf, Constitution Dock, Hoba ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Johnson Street Bridge
Four known bridges have spanned the narrows between the Inner Harbour and Upper Harbour of Victoria, British Columbia, connecting Johnson Street on the east shore with Esquimalt Road on the west shore. The current bridge is Canada's largest single-leaf bascule bridge. First bridge, 1855 - 1862 A low wagon bridge was completed in 1855, which blocked marine traffic. It was dismantled in 1862 and was replaced with a ferry service. Second bridge, 1888 - 1923 In 1888, a hand-operated swing bridge of limited load capacity was built for rail and foot traffic only. Third bridge, 1924-2018 Description The third Johnson Street Bridge was built as two adjacent, independent, heel trunnion bascule bridges, a three-lane road span of , and a single-track rail span of . The approaches were fixed steel girders; the east and the west . Counterweights were of hollow concrete weighing . Operating struts were moved by pinions powered by electric motors. History The Johnson Str ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Double-beam Drawbridge
A double-beam drawbridge, seesaw or folding bridge is a movable bridge . It opens by rotation about a horizontal axis parallel to the water. Historically, the double-beam drawbridge has emerged from the drawbridge. Unlike a drawbridge, a double-beam drawbridge has counterweights, so that opening requires much less energy. Unlike the bascule bridge, the simple drawbridge and the "oorgat" (earhole) bridge, the double-beam drawbridge has two hinges. The road surface is connected to the bottom hinge. Above the hinge is a portal, the hamei gate. A rotating arm, the balance, is attached to this hamei gate. On one side of the balance hangs the counterweight, the balance box, on the other side, the arm is connected to the tip of the bridge deck. So when the bridge goes up, the balance and the bridge deck turn parallel. The drawback of a traditional double-beam drawbridge is that it has a limited clearance height. That is why the balance box sometimes does not hang between the two arms, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pegasus Bridge
Pegasus Bridge, originally called the Bénouville Bridge after the neighbouring village, is a road crossing over the Caen Canal, between Caen and Ouistreham in Normandy. The original bridge, built in 1934, is now a war memorial and is the centrepiece of the Memorial Pegasus museum at nearby Ranville. It was replaced in 1994 by a modern design which, like the old one, is a bascule bridge. On 6 June 1944, during the Second World War, the bridge was, along with the nearby Ranville Bridge over the Orne River (another road crossing, later renamed Horsa Bridge), the objective of members of D Company, 2nd (Airborne) Battalion, Oxfordshire and Buckinghamshire Light Infantry, a glider-borne force who were part of the 6th Airlanding Brigade of the 6th Airborne Division during Operation Tonga in the opening minutes of the Allied invasion of Normandy. Under the command of Major John Howard, D Company was to land close by the bridges in six Airspeed Horsa gliders and, in a ''coup-de-main'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Henry Ford Bridge
The Henry Ford Bridge, also known as the Badger Avenue Bridge, is a bridge located in Los Angeles County, Southern California. It carries the Pacific Harbor Line railroad across the Cerritos Channel to Terminal Island from San Pedro, to serve the Port of Los Angeles and Port of Long Beach. It was built to accommodate operations at the Ford Long Beach Assembly plant which opened in 1930 and was closed in 1959. The original 1924 bascule bridge was dismantled and replaced in 1996 by a vertical-lift bridge. Bascule bridge The contract for the bascule bridge was placed by The Los Angeles Board of Harbor Commissioners in 1922. The bridge was designed by Joseph Baermann Strauss and fabricated by the American Bridge Company. It was formed of a pair of trunnion bascule leaves which formed a one span Warren through-truss. There were two tower spans and two timber approaches. See also * Commodore Schuyler F. Heim Bridge *Vincent Thomas Bridge *Bridges in Los Angeles County, Ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abutment
An abutment is the substructure at the ends of a bridge span or dam supporting its superstructure. Single-span bridges have abutments at each end which provide vertical and lateral support for the span, as well as acting as retaining walls to resist lateral movement of the earthen fill of the bridge approach. Multi-span bridges require piers to support ends of spans unsupported by abutments. Dam abutments are generally the sides of a valley or gorge, but may be artificial in order to support arch dams such as Kurobe Dam in Japan. The civil engineering term may also refer to the structure supporting one side of an arch, or masonry used to resist the lateral forces of a vault.Pevsner, N. (1970) ''Cornwall''; 2nd ed. Harmondsworth: Penguin; p. 245 The impost or abacus of a column in classical architecture may also serve as an abutment to an arch. The word derives from the verb "abut", meaning to "touch by means of a mutual border". Use in engineering An abutment may be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Library Of Congress
The Library of Congress (LOC) is the research library that officially serves the United States Congress and is the ''de facto'' national library of the United States. It is the oldest federal cultural institution in the country. The library is housed in three buildings on Capitol Hill in Washington, D.C.; it also maintains a conservation center in Culpeper, Virginia. The library's functions are overseen by the Librarian of Congress, and its buildings are maintained by the Architect of the Capitol. The Library of Congress is one of the largest libraries in the world. Its "collections are universal, not limited by subject, format, or national boundary, and include research materials from all parts of the world and in more than 470 languages." Congress moved to Washington, D.C., in 1800 after holding sessions for eleven years in the temporary national capitals in New York City and Philadelphia. In both cities, members of the U.S. Congress had access to the sizable collec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Broadway Bridge (Portland, Oregon)
The Broadway Bridge is a Rall-type bascule bridge spanning the Willamette River in Portland, Oregon, United States, built in 1913. It was Portland's first bascule bridge, and it continues to hold the distinction of being the longest span of its bascule design type in the world. It was added to the National Register of Historic Places in November 2012. History and description The bridge was anticipated to be the world's longest bascule bridge and there was competition between the Strauss, Scherzer, and Rall bascule design patent holders. The "Rall" was selected based on cost. Ralph Modjeski designed the structure, which opened on April 22, 1913, at a cost of $1.6 million. It was the world's longest double-leaf bascule bridge, of any bascule type, at the time. The bridge's name derives from the street it carries, Broadway, but at the time of the bridge's construction that street name was in use only east of the river. The westside portion of what is now Broadway had been named 7 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
