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32-464: The bridge was designed by Ira G. Hedrick and Robert E. Kremers , incorporating a bascule lift mechanism designed by Joseph Strauss . Including approaches, the Burnside has a total length of 2,308 ft (703 m) and a 251 ft (77 m) center span. While lowered, this span is normally 64 ft (20 m) above the river. The deck is made of concrete, which contributes to its being one of

64-460: A 2-span or 3-span cable-stayed bridge, the loads from the main spans are normally anchored back near the end abutments by stays in the end spans. For more spans, this is not the case and the bridge structure is less stiff overall. This can create difficulties in both the design of the deck and the pylons. Examples of multiple-span structures in which this is the case include Ting Kau Bridge , where additional 'cross-bracing' stays are used to stabilise

96-605: A final cost of $ 4.5 million (including approaches). It was the first Willamette River bridge in Portland designed with input from an architect. This led to the Italian Renaissance towers and decorative metal railings. The bascule system was designed by Joseph Strauss . The initial principal engineer for the bridge construction was the firm of Hedrick & Kremers. The bridge was then completed by Gustav Lindenthal , who also supervised its construction. Streetcars crossed

128-603: A local businessman who was a proponent of the 1866 dredging of the Willamette River. Construction of the original Burnside Bridge began in November 1892, and the bridge opened on July 4, 1894. It was a swing-span truss bridge made of wrought iron and steel. The replacement was part of a $ 4.5 million bond that also included the construction of the Ross Island and Sellwood bridges. The public would later learn that

160-647: Is a cable-stayed bridge with a more substantial bridge deck that, being stiffer and stronger, allows the cables to be omitted close to the tower and for the towers to be lower in proportion to the span. The first extradosed bridges were the Ganter Bridge and Sunniberg Bridge in Switzerland. The first extradosed bridge in the United States, the Pearl Harbor Memorial Bridge was built to carry I-95 across

192-500: 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 were being designed and constructed by the late 16th century, and the form found wide use in the late 19th century. Early examples, including the Brooklyn Bridge , often combined features from both

224-621: Is scheduled to open by 2031. Ira G. Hedrick Ira Grant Hedrick (April 6, 1868 – December 28, 1937) was an American civil engineer who designed the Burnside Bridge in Oregon , the Red River Bridge , Clarendon, and Newport bridges in Arkansas, and many other bridges and viaducts . Hedrick designed many large scale bridges in Arkansas in late 1920s through early 1930s. Hedrick

256-593: The Penobscot Narrows Bridge , completed in 2006, and the Veterans' Glass City Skyway , completed in 2007. A self-anchored suspension bridge has some similarity in principle to the cable-stayed type in that tension forces that prevent the deck from dropping are converted into compression forces vertically in the tower and horizontally along the deck structure. It is also related to the suspension bridge in having arcuate main cables with suspender cables, although

288-477: The Theodor Heuss Bridge (1958). However, this involves substantial erection costs, and more modern structures tend to use many more cables to ensure greater economy. Cable-stayed bridges may appear to be similar to suspension bridges , but they are quite different in principle and construction. In suspension bridges, large main cables (normally two) hang between the towers and are anchored at each end to

320-451: The live load of traffic crossing the bridge. The tension on the main cables is transferred to the ground at the anchorages and by downwards compression on the towers. In cable-stayed bridges, the towers are the primary load-bearing structures that transmit the bridge loads to the ground. A cantilever approach is often used to support the bridge deck near the towers, but lengths further from them are supported by cables running directly to

352-491: The 1924 contract was given for $ 500,000 more than the lowest bid. Having moved the bridge location to profit by selling their land, three Multnomah County commissioners were recalled as a result of the scandal, and a new engineering company assumed control of the project. The Ku Klux Klan had backed the commissioners and enabled their system of kickbacks and grafts; the ensuing "rotten bridge scandal" removed much of their clout even by 1924. The bridge opened on May 28, 1926, at

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384-535: The Burnside Bridge until 1950, and electric trolleybuses serving the Sandy Blvd. route did so from 1936 to 1958. Currently, three TriMet bus routes use the bridge. In the 1990s the Burnside Bridge was made a Regional Emergency Transportation Route, the one non-freeway bridge to be used by emergency vehicles. In 1995 one of the six lanes was removed to accommodate new bicycle lanes. From March until November 2002

416-499: The Donzère-Mondragon canal at Pierrelatte is one of the first of the modern type, but had little influence on later development. The steel-decked Strömsund Bridge designed by Franz Dischinger (1955) is, therefore, more often cited as the first modern cable-stayed bridge. Other key pioneers included Fabrizio de Miranda , Riccardo Morandi , and Fritz Leonhardt . Early bridges from this period used very few stay cables, as in

448-619: The Quinnipiac River in New Haven, Connecticut, opening in June 2012. A cradle system carries the strands within the stays from the bridge deck to bridge deck, as a continuous element, eliminating anchorages in the pylons. Each epoxy-coated steel strand is carried inside the cradle in a one-inch (2.54 cm) steel tube. Each strand acts independently, allowing for removal, inspection, and replacement of individual strands. The first two such bridges are

480-409: The bridge deck. A distinctive feature are the cables or 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

512-432: The bridge underwent a $ 2.1 million seismic retrofit, making it the first bridge operated by Multnomah County to receive earthquake protection. The bridge was under construction in 2006 in order to replace the deck. The electric streetcar tracks, abandoned in 1950, were visible during the construction. This project was budgeted at $ 9 million and the majority of the work was completed on December 9, 2007. The bridge

544-405: The cable-stayed and suspension designs. Cable-stayed designs fell from favor in the early 20th century as larger gaps were bridged using pure suspension designs, and shorter ones using various systems built of reinforced concrete . It returned to prominence in the later 20th century when the combination of new materials, larger construction machinery, and the need to replace older bridges all lowered

576-562: The cable-stayed bridge are balanced so that the supporting towers do not tend to tilt or slide and so must only resist horizontal forces from the live loads. The following are key advantages of the cable-stayed form: There are four major classes of rigging on cable-stayed bridges: mono , harp , fan, and star . There are also seven main arrangements for support columns: single , double , portal , A-shaped , H-shaped , inverted Y and M-shaped . The last three are hybrid arrangements that combine two arrangements into one. Depending on

608-674: The combination of technologies created a stiffer bridge. John A. Roebling took particular advantage of this to limit deformations due to railway loads in the Niagara Falls Suspension Bridge . The earliest known surviving example of a true cable-stayed bridge in the United States is E.E. Runyon's largely intact steel or iron Bluff Dale Suspension bridge with wooden stringers and decking in Bluff Dale, Texas (1890), or his weeks earlier but ruined Barton Creek Bridge between Huckabay, Texas and Gordon, Texas (1889 or 1890). In

640-478: The current short-span bridge would not survive a major earthquake, and recommended a replacement long-span bridge. Early concepts for the new bridge included designs that resembled nearby Willamette River bridges; the six finalists, organized into cable-stayed and tied-arch designs, were presented for a public vote in July 2024. The replacement is estimated to cost $ 895 million and would begin construction in 2026; it

672-568: The design, the columns may be vertical or angled or curved relative to the bridge deck. A side-spar cable-stayed bridge uses a central tower supported only on one side. This design allows the construction of a curved bridge. Far more radical in its structure, the Puente del Alamillo (1992) uses a single cantilever spar on one side of the span, with cables on one side only to support the bridge deck. Unlike other cable-stayed types, this bridge exerts considerable overturning force upon its foundation and

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704-436: The ground. This can be difficult to implement when ground conditions are poor. The main cables, which are free to move on bearings in the towers, bear the load of the bridge deck. Before the deck is installed, the cables are under tension from their own weight. Along the main cables smaller cables or rods connect to the bridge deck, which is lifted in sections. As this is done, the tension in the cables increases, as it does with

736-465: The heaviest bascule bridges in the United States. The counterweights , housed inside the two piers, weigh 1,700 short tons (1,518 long tons; 1,542 t). The lifting is normally controlled by the Hawthorne Bridge operator, but an operator staffs the west tower during high river levels. As of 2005, the bridge opened for river traffic an average of 35 times a month. The bridge provides shelter for

768-476: The initially unauthorized Burnside Skatepark under the east end. On weekends, the Portland Saturday Market was held mostly under the bridge's west end for many years. The market was reoriented in 2009, but the Burnside Bridge continues to provide shelter for a few vendor stalls at the market's northern end. In 1891, Burnside Street was renamed from "B" street to take the name of Dan Wyman Burnside,

800-539: The pylons; Millau Viaduct and Mezcala Bridge , where twin-legged towers are used; and General Rafael Urdaneta Bridge , where very stiff multi-legged frame towers were adopted. A similar situation with a suspension bridge is found at both the Great Seto Bridge and San Francisco–Oakland Bay Bridge where additional anchorage piers are required after every set of three suspension spans – this solution can also be adapted for cable-stayed bridges. An extradosed bridge

832-510: The relative price of these designs. Cable-stayed bridges date back to 1595, where designs were found in Machinae Novae , a book by Croatian - Venetian inventor Fausto Veranzio . Many early suspension bridges were cable-stayed construction, including the 1817 footbridge Dryburgh Abbey Bridge , James Dredge 's patented Victoria Bridge, Bath (1836), and the later Albert Bridge (1872) and Brooklyn Bridge (1883). Their designers found that

864-512: The spar must resist the bending caused by the cables, as the cable forces are not balanced by opposing cables. The spar of this particular bridge forms the gnomon of a large garden sundial . Related bridges by the architect Santiago Calatrava include the Puente de la Mujer (2001), Sundial Bridge (2004), Chords Bridge (2008), and Assut de l'Or Bridge (2008). Cable-stayed bridges with more than three spans involve significantly more challenging designs than do 2-span or 3-span structures. In

896-411: The towers. That has the disadvantage, unlike for the suspension bridge, that the cables pull to the sides as opposed to directly up, which requires the bridge deck to be stronger to resist the resulting horizontal compression loads, but it has the advantage of not requiring firm anchorages to resist the horizontal pull of the main cables of the suspension bridge. By design, all static horizontal forces of

928-524: The twentieth century, early examples of cable-stayed bridges included A. Gisclard's unusual Cassagnes bridge (1899), in which the horizontal part of the cable forces is balanced by a separate horizontal tie cable, preventing significant compression in the deck, and G. Leinekugel le Coq's bridge at Lézardrieux in Brittany (1924). Eduardo Torroja designed a cable-stayed aqueduct at Tempul in 1926. Albert Caquot 's 1952 concrete-decked cable-stayed bridge over

960-535: Was added to the National Register of Historic Places in November 2012. The Eastbank Esplanade , which opened in 2001, is connected to the bridge by stairs added during the esplanade's construction. However, because of the bridge's age, it cannot support any extra weight, so the stairways must be supported by separate pilings. In 2020, the Earthquake Ready Burnside Bridge project deemed that

992-638: Was also president of the Kansas City Viaduct and Terminal Railway Company. The Historic American Engineering Record says that he was "one of the outstanding engineers of the South". Hedrick was a member of the American Society of Civil Engineers . In 1899, Hedrick was promoted by J.A.L. Waddell from Chief Draftsman to Partner of the firm Waddell & Hedrick , where he assisted in the design of Canada's New Westminster Bridge (opened 1904). Hedrick

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1024-538: Was born in West Salem, Illinois . He received his B.S. in civil engineering University of Arkansas at Fayetteville in 1892. He received another bachelor's degree from the university in 1899 in Applied Science and M.S. degree in 1901. He earned his D.Sc. degree from McGill University in 1905. Cable-stayed bridge A cable-stayed bridge has one or more towers (or pylons ), from which cables support

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