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Outline Of Bridges
The following outline is provided as an overview of and topical guide to bridges: Bridges – a structure built to span physical obstacles without closing the way underneath such as a body of water, valley, or road, for the purpose of providing passage over the obstacle. What type of thing is a bridge? Bridges can be described as all of the following: * A structure – An arrangement and organization of interrelated elements in a material object or system, or the object or system so organized. * A thoroughfare – A road connecting one location to another. Types of bridges * Beam Bridge *Truss Bridge ** Truss arch bridge *Cantilever Bridge * Stressed ribbon bridge *Arch Bridge ** Tied Arch Bridge **Through arch bridge **Skew arch *Suspension Bridge **Cable-stayed bridge *Simple suspension bridge ** Inca rope bridge * Tubular bridge *Extradosed bridge *Moveable Bridge **Drawbridge (British English definition) – the bridge deck is hinged on one end **Bascu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cable-stayed Bridge
A cable-stayed bridge has one or more ''towers'' (or ''pylons''), from which wire rope, cables support the bridge deck. A distinctive feature are the cables or wikt:stay#Etymology 3, stays, which run directly from the tower to the deck, normally forming a fan-like pattern or a series of parallel lines. This is in contrast to the modern suspension bridge, where the cables supporting the deck are suspended vertically from the main cable, anchored at both ends of the bridge and running between the towers. The cable-stayed bridge is optimal for spans longer than cantilever bridges and shorter than suspension bridges. This is the range within which cantilever bridges would rapidly grow heavier, and suspension bridge cabling would be more costly. Cable-stayed bridges found wide use in the late 19th century. Early examples, including the Brooklyn Bridge, often combined features from both the cable-stayed and suspension designs. Cable-stayed designs fell from favor in the early 20th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vertical-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. Most vertical-lift bridges use towers, each equipped with counterweights. An example of this kind was built in Portland, Oregon, U ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Merchant Square Footbridge
The Merchant Square Footbridge (also known as The Fan Bridge) is a moveable pedestrian bridge spanning a canal in Paddington, London. It is composed of five side-by side sections of varying lengths, with offset pivots to accommodate the varying lengths. When opened, the segments are brought to varying angles of elevation. The visual effect when opened has been likened to that of a Japanese fan. Not to be confused with the Fan Bridge which crosses Holland Brook (formerly known as the Holland River) between Little Clacton and Great Holland in Essex (UK) (OS Grid Ref: TM 19710 18667 / Latitude 51°49'24"N Longitude 1°11'12"E). This was the lowest crossing-point until the Gunfleet estuary was reclaimed in the 1700s. See also * List of bridges in London * Moveable bridges 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 b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Rolling Bridge
The Rolling Bridge is a kinetic sculpture, and a unique type of curling moveable bridge, completed in 2004 as part of the Grand Union Canal office and retail development project at Paddington Basin, London. Design The Rolling Bridge was conceived by Thomas Heatherwick. It consists of eight triangular sections hinged at the walkway level and connected above by two-part links that can be collapsed towards the deck by hydraulic cylinders mounted vertically between the sections. When extended, it resembles a conventional steel and timber footbridge, and is 12 metres long. To retract the bridge, the hydraulic pistons are activated and the bridge curls up until its two ends join, to form an octagonal shape measuring one half of the waterway's width at that point. The bridge won the British Constructional Steelwork Association's British Structural Steel Design Award. Disadvantages The Rolling Bridge could theoretically allow the passage of boats, but the small basin behind the b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Folding Bridge
A folding bridge is a type of moveable bridge engineered to fold. This allows ship traffic to pass through the waterway that the bridge spans. An example of a folding bridge is the Hörnbrücke ( Hörn Bridge) in the city of Kiel in the German state of Schleswig-Holstein. When the bridge is down it spans across the Kiel Fjord, known as the Hörn. The three-segment bascule bridge folds up into the shape of the capital letter ''N'' to allow for ship and boat traffic. See also * Bascule bridge * Double-beam drawbridge * Drawbridge * Moveable bridges 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 ... for a list of other moveable bridge types References Moveable bridges Bridges by structural type {{Bridge-type-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rack And Pinion
rack and pinion is a type of linear actuator that comprises a circular gear (the '' pinion'') engaging a linear gear (the ''rack''). Together, they convert between rotational motion and linear motion: rotating the pinion causes the rack to be driven in a line. Conversely, moving the rack linearly will cause the pinion to rotate. The rack and pinion mechanism is used in rack railways, where the pinion mounted on a locomotive or a railroad car engages a rack usually placed between the rails, and helps to move the train up a steep gradient. It is also used in arbor presses and drill presses, where the pinion is connected to a lever and displaces a vertical rack (the ram). In pipelines and other industrial piping systems, a rack displaced by a linear actuator turns a pinion to open or close a valve. Stairlifts, lock gates, electric gates, and the mechanical steering mechanism of cars are other notable applications. The term "rack and pinion" may be used also when the rac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bascule 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
British English
British English is the set of Variety (linguistics), varieties of the English language native to the United Kingdom, especially Great Britain. More narrowly, it can refer specifically to the English language in England, or, more broadly, to the collective dialects of English throughout the United Kingdom taken as a single umbrella variety, for instance additionally incorporating Scottish English, Welsh English, and Northern Irish English. Tom McArthur (linguist), Tom McArthur in the Oxford English Dictionary, Oxford Guide to World English acknowledges that British English shares "all the ambiguities and tensions [with] the word 'British' and as a result can be used and interpreted in two ways, more broadly or more narrowly, within a range of blurring and ambiguity". Variations exist in formal (both written and spoken) English in the United Kingdom. For example, the adjective ''wee'' is almost exclusively used in parts of Scotland, north-east England, Northern Ireland, Ireland ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drawbridge
A drawbridge or draw-bridge is a type of moveable bridge typically at the entrance to a castle or tower surrounded by a moat. In some forms of English, including American English, the word ''drawbridge'' commonly refers to all types of moveable bridges, such as bascule bridges, vertical-lift bridges and swing bridges, but this article concerns the narrower historical definition where the bridge is used in a defensive structure. As used in castles or defensive structures, drawbridges provide access across defensive structures when lowered, but can quickly be raised from within to deny entry to an enemy force. Castle drawbridges Middle Ages, Medieval castles were usually defended by a ditch or moat, crossed by a wooden bridge. In early castles, the bridge might be designed to be destroyed or removed in the event of an attack, but drawbridges became very common. A typical arrangement would have the drawbridge immediately outside a gatehouse, consisting of a wooden Deck (bridge), ... [...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-c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extradosed Bridge
An extradosed bridge employs a structure that combines the main elements of both a prestressed box girder bridge and a cable-stayed bridge. The name comes from the word ''wikt:extrados, extrados'', the exterior or upper curve of an arch, and refers to how the "stay cables" on an extradosed bridge are not considered as such in the design, but are instead treated as external Prestressed concrete, prestressing tendons deviating upward from the deck. In this concept, they remain part of (and define the upper limit of) the main bridge superstructure. Compared to a cable-stayed or cantilever bridge, cantilever-girder bridge of comparable span, an extradosed bridge uses much shorter stay-towers or pylons than the cable-stayed bridge, and a significantly shallower deck/girder structure than used on the girder bridge. This arrangement results in the typical extradosed "look" of a fan of low, shallow-angle stay cables, usually with a pronounced "open window" region extending from the sides ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
