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32-640: The Cowen Park Bridge is a reinforced concrete arch bridge in Seattle , Washington . The bridge has a length of 358 feet (109 m) and carries 15th Avenue NE across a ravine in the Cowen Park . The bridges acts as a dividing line in the Ravenna-Cowen Park contiguous area, with the smaller area west of the bridge deemed Cowen Park and the larger area east of the bridge considered Ravenna Park. The bridge, which spans from NE 62nd Street to Cowen Place NE, connects

64-505: A deck arch bridge. Any part supported from arch below may have spandrels that are closed or open. The Sydney Harbour Bridge and the Bayonne Bridge are a through arch bridge which uses a truss type arch. Also known as a bowstring arch, this type of arch bridge incorporates a tie between two opposite ends of the arch. The tie is usually the deck and is capable of withstanding the horizontal thrust forces which would normally be exerted on

96-458: A greater passage for flood waters. Bridges with perforated spandrels can be found worldwide, such as in China ( Zhaozhou Bridge , 7th century). Greece ( Bridge of Arta , 17th century) and Wales ( Cenarth Bridge , 18th century). In more modern times, stone and brick arches continued to be built by many civil engineers, including Thomas Telford , Isambard Kingdom Brunel and John Rennie . A key pioneer

128-411: A member of the gens Fabricia of Rome. Completely intact from Roman antiquity, it has been in continuous use ever since. The Pons Fabricius has a length of 62 m, and is 5.5 m wide. It is constructed from two wide arches spanning 80 feet, supported by a central pillar in the middle of the stream. The arches of this bridge are the first ones on any Roman bridge that were not semi-circular. This

160-448: A quantity of fill material (typically compacted rubble) above the arch in order to increase this dead-weight on the bridge and prevent tension from occurring in the arch ring as loads move across the bridge. Other materials that were used to build this type of bridge were brick and unreinforced concrete. When masonry (cut stone) is used the angles of the faces are cut to minimize shear forces. Where random masonry (uncut and unprepared stones)

192-415: A result, masonry arch bridges are designed to be constantly under compression, so far as is possible. Each arch is constructed over a temporary falsework frame, known as a centring . In the first compression arch bridges, a keystone in the middle of the bridge bore the weight of the rest of the bridge. The more weight that was put onto the bridge, the stronger its structure became. Masonry arch bridges use

224-430: A three-hinged bridge has hinged in all three locations. Most modern arch bridges are made from reinforced concrete . This type of bridge is suitable where a temporary centring may be erected to support the forms, reinforcing steel, and uncured concrete. When the concrete is sufficiently set the forms and falseworks are then removed. It is also possible to construct a reinforced concrete arch from precast concrete , where

256-576: Is a stub . You can help Misplaced Pages by expanding it . Arch bridge Possibly the oldest existing arch bridge is the Mycenaean Arkadiko Bridge in Greece from about 1300 BC. The stone corbel arch bridge is still used by the local populace. The well-preserved Hellenistic Eleutherna Bridge has a triangular corbel arch. The 4th century BC Rhodes Footbridge rests on an early voussoir arch. Although true arches were already known by

288-428: Is a masonry, or stone, bridge where each successively higher course (layer) cantilevers slightly more than the previous course. The steps of the masonry may be trimmed to make the arch have a rounded shape. The corbel arch does not produce thrust, or outward pressure at the bottom of the arch, and is not considered a true arch . It is more stable than a true arch because it does not have this thrust. The disadvantage

320-588: Is listed in the National Register of Historic Places , and it is a designated city landmark . The bridge has been praised for the 12 ft (3.7 m) Art Deco light standards along its sides. This article about a bridge in the U.S. state of Washington is a stub . You can help Misplaced Pages by expanding it . This article about a property in Washington on the National Register of Historic Places

352-543: Is possibly caused by the semi-circle being located below the water line. Its core is constructed of tuff . Its outer facing today is made of bricks and travertine . A relief is located 20 feet above the pier. During times of flood , this relief served as an additional waterway . An original inscription on the travertine commemorates its builder in Latin: L . FABRICIVS . C . F . CVR . VIAR | FACIVNDVM . COERAVIT | IDEMQVE | PROBAVIT ("Lucius Fabricius, son of Gaius, superintendent of

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384-432: Is that this type of arch is not suitable for large spans. In some locations it is necessary to span a wide gap at a relatively high elevation, such as when a canal or water supply must span a valley. Rather than building extremely large arches, or very tall supporting columns (difficult using stone), a series of arched structures are built one atop another, with wider structures at the base. Roman civil engineers developed

416-402: Is used they are mortared together and the mortar is allowed to set before the falsework is removed. Traditional masonry arches are generally durable, and somewhat resistant to settlement or undermining. However, relative to modern alternatives, such bridges are very heavy, requiring extensive foundations . They are also expensive to build wherever labor costs are high. The corbel arch bridge

448-549: The Etruscans and ancient Greeks , the Romans were – as with the vault and the dome – the first to fully realize the potential of arches for bridge construction. A list of Roman bridges compiled by the engineer Colin O'Connor features 330 Roman stone bridges for traffic, 34 Roman timber bridges and 54 Roman aqueduct bridges , a substantial part still standing and even used to carry vehicles. A more complete survey by

480-517: The Italian scholar Vittorio Galliazzo found 931 Roman bridges, mostly of stone, in as many as 26 countries (including former Yugoslavia ). Roman arch bridges were usually semicircular , although a number were segmental arch bridges (such as Alconétar Bridge ), a bridge which has a curved arch that is less than a semicircle. The advantages of the segmental arch bridge were that it allowed great amounts of flood water to pass under it, which would prevent

512-436: The abutments of an arch bridge. The deck is suspended from the arch. The arch is in compression, in contrast to a suspension bridge where the catenary is in tension. A tied-arch bridge can also be a through arch bridge. An arch bridge with hinges incorporated to allow movement between structural elements. A single-hinged bridge has a hinge at the crown of the arch , a two-hinged bridge has hinges at both springing points and

544-761: The acclaimed Florentine segmental arch bridge Ponte Vecchio (1345) combined sound engineering (span-to-rise ratio of over 5.3 to 1) with aesthetical appeal. The three elegant arches of the Renaissance Ponte Santa Trinita (1569) constitute the oldest elliptic arch bridge worldwide. Such low rising structures required massive abutments , which at the Venetian Rialto bridge and the Fleischbrücke in Nuremberg (span-to-rise ratio 6.4:1) were founded on thousands of wooden piles, partly rammed obliquely into

576-416: The arch and the deck is known as the spandrel . If the spandrel is solid, usually the case in a masonry or stone arch bridge, the bridge is called a closed-spandrel deck arch bridge . If the deck is supported by a number of vertical columns rising from the arch, the bridge is known as an open-spandrel deck arch bridge . The Alexander Hamilton Bridge is an example of an open-spandrel arch bridge. Finally, if

608-400: The arch is built in two halves which are then leaned against each other. Many modern bridges, made of steel or reinforced concrete, often bear some of their load by tension within their structure. This reduces or eliminates the horizontal thrust against the abutments and allows their construction on weaker ground. Structurally and analytically they are not true arches but rather a beam with

640-422: The arch supports the deck only at the top of the arch, the bridge is called a cathedral arch bridge . This type of bridge has an arch whose base is at or below the deck, but whose top rises above it, so the deck passes through the arch. The central part of the deck is supported by the arch via suspension cables or tie bars, as with a tied-arch bridge . The ends of the bridge may be supported from below, as with

672-615: The bridge an unusually flat profile unsurpassed for more than a millennium. Trajan's bridge over the Danube featured open- spandrel segmental arches made of wood (standing on 40 m-high (130 ft) concrete piers). This was to be the longest arch bridge for a thousand years both in terms of overall and individual span length, while the longest extant Roman bridge is the 790 m-long (2,590 ft) long Puente Romano at Mérida . The late Roman Karamagara Bridge in Cappadocia may represent

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704-447: The bridge from being swept away during floods and the bridge itself could be more lightweight. Generally, Roman bridges featured wedge-shaped primary arch stones ( voussoirs ) of the same in size and shape. The Romans built both single spans and lengthy multiple arch aqueducts , such as the Pont du Gard and Segovia Aqueduct . Their bridges featured from an early time onwards flood openings in

736-414: The design and constructed highly refined structures using only simple materials, equipment, and mathematics. This type is still used in canal viaducts and roadways as it has a pleasing shape, particularly when spanning water, as the reflections of the arches form a visual impression of circles or ellipses. This type of bridge comprises an arch where the deck is completely above the arch. The area between

768-550: The earliest surviving bridge featuring a pointed arch. In medieval Europe, bridge builders improved on the Roman structures by using narrower piers , thinner arch barrels and higher span-to-rise ratios on bridges. Gothic pointed arches were also introduced, reducing lateral thrust, and spans increased as with the eccentric Puente del Diablo (1282). The 14th century in particular saw bridge building reaching new heights. Span lengths of 40 m (130 ft), previously unheard of in

800-492: The grounds to counteract more effectively the lateral thrust. In China, the oldest existing arch bridge is the Zhaozhou Bridge of 605 AD, which combined a very low span-to-rise ratio of 5.2:1, with the use of spandrel arches (buttressed with iron brackets). The Zhaozhou Bridge, with a length of 167 feet (51 m) and span of 123 feet (37 m), is the world's first wholly stone open-spandrel segmental arch bridge, allowing

832-443: The history of masonry arch construction, were now reached in places as diverse as Spain ( Puente de San Martín ), Italy ( Castelvecchio Bridge ) and France ( Devil's bridge and Pont Grand ) and with arch types as different as semi-circular, pointed and segmental arches. The bridge at Trezzo sull'Adda , destroyed in the 15th century, even featured a span length of 72 m (236 ft), not matched until 1796. Constructions such as

864-615: The northern Roosevelt / Ravenna neighborhood with the beginning of the University District . The Cowen Park Bridge is one of two bridges that span the Ravenna Park ravine (the other being the 20th Avenue NE Bridge built in 1913) but is the only one open to vehicular traffic. The bridge was built in 1936 under the authority of the Works Progress Administration . The bridge engineer was Clark Eldridge . The structure

896-821: The piers, e.g. in the Pons Fabricius in Rome (62 BC), one of the world's oldest major bridges still standing. Roman engineers were the first and until the Industrial Revolution the only ones to construct bridges with concrete , which they called Opus caementicium . The outside was usually covered with brick or ashlar , as in the Alcántara Bridge . The Romans also introduced segmental arch bridges into bridge construction. The 330 m-long (1,080 ft) Limyra Bridge in southwestern Turkey features 26 segmental arches with an average span-to-rise ratio of 5.3:1, giving

928-451: The shape of an arch. See truss arch bridge for more on this type. A modern evolution of the arch bridge is the long-span through arch bridge . This has been made possible by the use of light materials that are strong in tension such as steel and prestressed concrete. "The Romans were the first builders in Europe, perhaps the first in the world, fully to appreciate the advantages of the arch,

960-399: The two marble pillars of the two-faced Janus herms on the parapet, which were moved here from the nearby Church of St Gregory (Monte Savello) in the 14th century. According to Dio Cassius , the bridge was built in 62 BC, the year after Cicero was consul , to replace an earlier wooden bridge destroyed by fire. It was commissioned by Lucius Fabricius, the curator of the roads and

992-628: The vault and the dome." Pons Fabricius The Pons Fabricius ( Italian : Ponte Fabricio , "Fabrician Bridge") or Ponte dei Quattro Capi , is the oldest extant bridge in Rome , Italy . Built in 62 BC, it spans half of the Tiber River, from the Campus Martius on the east side to Tiber Island in the middle (the Pons Cestius is west of the island). Quattro Capi ("four heads") refers to

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1024-402: Was Jean-Rodolphe Perronet , who used much narrower piers, revised calculation methods and exceptionally low span-to-rise ratios. Different materials, such as cast iron , steel and concrete have been increasingly used in the construction of arch bridges. Stone, brick and other such materials are strong in compression and somewhat so in shear , but cannot resist much force in tension . As

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