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62-506: It is the longest suspension bridge in Brazil. The central span was considered quite long (but not the longest, at 340 metres) at the time of its opening and is still one of the 100 largest suspension bridges . Construction commenced on 14 November 1922 with the bridge being inaugurated on May 13, 1926. The total length is 819.471 metres, with 259 metres of viaduct from the island, a central span of 339.471 metres and 221 metres of viaduct from

124-410: A cable-stayed bridge in which the deck is in compression. Cable-stayed bridges and suspension bridges may appear to be similar, but are quite different in principle and in their construction. In suspension bridges, large main cables (normally two) hang between the towers and are anchored at each end to the ground. The main cables, which are free to move on bearings in the towers, bear the load of

186-460: A 200 feet span (also termed Beose Bridge) was constructed near Sagar, India during 1828–1830 by Duncan Presgrave, Mint and Assay Master. The Clifton Suspension Bridge (designed in 1831, completed in 1864 with a 214 m central span), is similar to the Sagar bridge. It is one of the longest of the parabolic arc chain type. The current Marlow suspension bridge was designed by William Tierney Clark and

248-492: A bridge has a tendency to collapse simply because of the gravitational forces acting on the materials of which the bridge is made. Live load refers to traffic that moves across the bridge as well as normal environmental factors such as changes in temperature, precipitation, and winds. Dynamic load refers to environmental factors that go beyond normal weather conditions, factors such as sudden gusts of wind and earthquakes. All three factors must be taken into consideration when building

310-468: A bridge. Silver Bridge (USA) was an eyebar chain highway bridge, built in 1928, that collapsed in late 1967, killing forty-six people. The bridge had a low-redundancy design that was difficult to inspect. The collapse inspired legislation to ensure that older bridges were regularly inspected and maintained. Following the collapse a bridge of similar design was immediately closed and eventually demolished. A second similarly-designed bridge had been built with

372-788: A bridge. The principles of suspension used on a large scale also appear in contexts less dramatic than road or rail bridges. Light cable suspension may prove less expensive and seem more elegant for a cycle or footbridge than strong girder supports. An example of this is the Nescio Bridge in the Netherlands, and the Roebling designed 1904 Riegelsville suspension pedestrian bridge across the Delaware River in Pennsylvania. The longest pedestrian suspension bridge, which spans

434-421: A degree of hardness exceeding that of the bars so that they will not shear under high stress. Original eyebars were formed from "piling" thin iron metal on top of one another and forging it together in a furnace. Once together the piece was heated and hammered into a U shape over a die. To create the eye the heated bent iron was hammered into itself closing the gap and creating the eye shape. This method created

496-403: A higher margin of safety and remained in service until 1991. The Tacoma Narrows Bridge , (USA), 1940, was vulnerable to structural vibration in sustained and moderately strong winds due to its plate-girder deck structure. Wind caused a phenomenon called aeroelastic fluttering that led to its collapse only months after completion. The collapse was captured on film. There were no human deaths in

558-570: A historical and artistic monument. Restoration of the bridge was investigated by a partnership involving the Federal Government, State Government, and the Municipality of Florianópolis. Submission of restoration plans occurred in mid-2013. Restoration work on the approach spans began in 2006, and was completed in 2008 at a cost of R$ 21,000,000. Restoration work on the main span was supposed to begin in 2009, but after delays by

620-494: A number of eyebar links combed together to form a highly redundant structure. This use of eyebar places it in a chain linkage that is holding a load based on tension rather than compression. However, more modern low-redundancy chain link suspension spans fell into general disfavor as a result of the collapse of the Silver Bridge in 1967, which led to the deaths of 46 people. (The current method of suspension bridge design

682-504: A pedestrian suspension bridge over the Machchhu River in the city of Morbi, Gujarat, India collapsed, leading to the deaths of at least 141 people. Eyebar In structural engineering and construction, an eyebar is a straight bar, usually of metal , with a hole ("eye") at each end for fixing to other components. Eyebars are used in structures such as bridges , in settings in which only tension , and never compression ,

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744-647: A proposal by Robert Stevenson for a bridge over the River Almond near Edinburgh . Roebling's Delaware Aqueduct (begun 1847) consists of three sections supported by cables. The timber structure essentially hides the cables; and from a quick view, it is not immediately apparent that it is even a suspension bridge. The main suspension cables in older bridges were often made from a chain or linked bars, but modern bridge cables are made from multiple strands of wire. This not only adds strength but improves reliability (often called redundancy in engineering terms) because

806-427: A quick and efficient way to create the bar, however would not structurally stay together after a certain point due to the piling method being ill heated or being defective. Piling was superseded by casting, wherein the eye and the bar are cast together in the same mold, creating a more sound piece with less area for the bond to break apart. Newer methods of steel cutting such as laser / plasma / and water-jetting allow

868-553: A result, the steel pins in the eyes become loose and lose tension, which in turn compromises the integrity of the structure. Due to the technological advancements in creating eyebars, iron and old cast method of steel eyebars are less common. These older bridges however still need to be maintained and reviewed. Researchers like Dewey Walls Jr. of the Union Pacific Railroad have compiled resources on how to review, identify compromised locations and how to properly repair

930-541: A sequence generally described as follows. Depending on length and size, construction may take anywhere between a year and a half (construction on the original Tacoma Narrows Bridge took only 19 months) up to as long as a decade (the Akashi-Kaikyō Bridge's construction began in May 1986 and was opened in May 1998 – a total of twelve years). Suspension bridges are typically ranked by the length of their main span. These are

992-499: A temporary walkway. Poured sockets are used to make a high strength, permanent cable termination. They are created by inserting the suspender wire rope (at the bridge deck supports) into the narrow end of a conical cavity which is oriented in-line with the intended direction of strain. The individual wires are splayed out inside the cone or 'capel', and the cone is then filled with molten lead-antimony-tin (Pb80Sb15Sn5) solder. Most suspension bridges have open truss structures to support

1054-509: Is applied. Also referred to as "pin- and eyebar construction" in instances where pins are being used. A closed eyebar will typically have a rectangular cross section of constant thickness throughout its length and a constant width for all but the ends. The ends will transition to a wider part that is terminated by a rounded end. In the center of this end will be a hole which will receive a cylindrical pin, which may have provision to accept one or more nuts or bolts . If of round cross section

1116-645: Is considered the last remaining Inca rope bridge and is rebuilt annually. The first iron chain suspension bridge in the Western world was the Jacob's Creek Bridge (1801) in Westmoreland County, Pennsylvania , designed by inventor James Finley . Finley's bridge was the first to incorporate all of the necessary components of a modern suspension bridge, including a suspended deck which hung by trusses. Finley patented his design in 1808, and published it in

1178-461: Is to use multiple strands of drawn wire to form substantial cables.) Eyebars may be cast , forged , or cut from rolled plate. If round stock is used the eyes will usually be forged. Heat treatment (heating and rapid cooling) will result in a fine-grained microscopic crystal structure, enhancing the strength of the bar. Excessive hardness may induce brittleness, which should be avoided. The pins used to join bars will also be heat treated, usually to

1240-765: The American Bridge Company (ABC). All the material it used was brought from the United States. It has the fairly unusual feature that the truss carrying the roadway (a continuous stiffening component) is above the roadway itself and meets up with the eyebar chains making it non-uniform in height. A similar bridge, the Walter Taylor Bridge , was built over the Brisbane River in Brisbane , Australia in 1936. When completed

1302-836: The Mahakam River , located in Kutai Kartanegara Regency , East Kalimantan district on the Indonesia island of Borneo , was built in 1995, completed in 2001 and collapsed in 2011. Dozens of vehicles on the bridge fell into the Mahakam River . As a result of this incident, 24 people died and dozens of others were injured and were treated at the Aji Muhammad Parikesit Regional Hospital. Meanwhile, 12 people were reported missing, 31 people were seriously injured, and 8 people had minor injuries. Research findings indicate that

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1364-777: The Philadelphia journal, The Port Folio , in 1810. Early British chain bridges included the Dryburgh Abbey Bridge (1817) and 137 m Union Bridge (1820), with spans rapidly increasing to 176 m with the Menai Bridge (1826), "the first important modern suspension bridge". The first chain bridge on the German speaking territories was the Chain Bridge in Nuremberg . The Sagar Iron Suspension Bridge with

1426-552: The River Paiva, Arouca Geopark , Portugal, opened in April 2021. The 516 metres bridge hangs 175 meters above the river. Where such a bridge spans a gap between two buildings, there is no need to construct towers, as the buildings can anchor the cables. Cable suspension may also be augmented by the inherent stiffness of a structure that has much in common with a tubular bridge . Typical suspension bridges are constructed using

1488-584: The U.S., collapsed in 1967 due to a failure in one of the eyebars. Luz didn't get to see his bridge completed, dying in 1924 twelve days after having inaugurated a wooden replica built in XV Square specifically for the symbolic act. Originally intended to be named the Independence Bridge this was changed after Luz's death in a posthumous tribute. The bridge was inaugurated on May 13, 1926. The steel structure weighs approximately 5,000 tons, and

1550-425: The bar will typically be end-forged to create a head, which is then flatted by additional forging. The head may then be machined to a precise thickness and flatness. An alternative method for using round bar is to form a loop and to forge-weld (hammer weld) or electrically weld the free end to the main bar. Open eyebars are not used in the cable anchorages of modern wire-cable suspension bridges. This does not allow

1612-432: 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 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

1674-458: The bridge is carrying one traffic lane in each direction, as well as bicycle and pedestrian paths. Several additions have been made to the original contracted cost. The final cost of the restoration is currently expected to be R$ 333,000,000 The first eyebar was replaced on March 21, 2018 and the bridge's re-opening was on December 30, 2019, although some of the temporary supporting structures will not be removed until March 2020. In December 2019,

1736-468: The bridge was the longest eyebar suspension span in existence at that time. The 1,113’ long design features towers with rocker bearings. ABC brought to the project its own experimental heat-treated eyebars, and as project contractor pioneered stiffening techniques that saved materials and money while providing greater rigidity. Another bridge of similar design, the Silver Bridge over the Ohio River in

1798-491: The chains are not attached to abutments as is usual, but instead are attached to the main girders, which are thus in compression. Here, the chains are made from flat wrought iron plates, eight inches (203 mm) wide by an inch and a half (38 mm) thick, rivetted together. The first wire-cable suspension bridge was the Spider Bridge at Falls of Schuylkill (1816), a modest and temporary footbridge built following

1860-631: The collapse of James Finley's nearby Chain Bridge at Falls of Schuylkill (1808). The footbridge's span was 124 m, although its deck was only 0.45 m wide. Development of wire-cable suspension bridges dates to the temporary simple suspension bridge at Annonay built by Marc Seguin and his brothers in 1822. It spanned only 18 m. The first permanent wire cable suspension bridge was Guillaume Henri Dufour 's Saint Antoine Bridge in Geneva of 1823, with two 40 m spans. The first with cables assembled in mid-air in

1922-529: The collapse was largely caused by the construction failure of the vertical hanging clamp. It was also found that poor maintenance, fatigue in the cable hanger construction materials, material quality, and bridge loads that exceed vehicle capacity, can also have an impact on bridge collapse. In 2013 the Kutai Kartanegara Bridge rebuilt the same location and completed in 2015 with a Through arch bridge design. On 30 October 2022, Jhulto Pul ,

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1984-522: The collapse; several drivers escaped their cars on foot and reached the anchorages before the span dropped. Yarmouth suspension bridge (England) was built in 1829 and collapsed in 1845, killing 79 people. Peace River Suspension Bridge (Canada), which was completed in 1943, collapsed when the north anchor's soil support for the suspension bridge failed in October 1957. The entire bridge subsequently collapsed. Kutai Kartanegara Bridge (Indonesia) over

2046-475: The contractor the contract was split into two parts. Rehabilitation of the bridge was started in 2016 by the Portuguese company Teixeira Duarte. Four midspan piers and an under-deck truss were constructed to support the bridge deck during the restoration. The restoration was extensive, involving the replacement of the entire eyebar suspension system, and the pin joints at the bases of the towers. Once reopened

2108-417: The deck below, upon which traffic crosses. This arrangement allows the deck to be level or to arc upward for additional clearance. Like other suspension bridge types, this type often is constructed without the use of falsework . The suspension cables must be anchored at each end of the bridge, since any load applied to the bridge is transformed into tension in these main cables. The main cables continue beyond

2170-418: The early 1800s. Simple suspension bridges , which lack vertical suspenders, have a long history in many mountainous parts of the world. Besides the bridge type most commonly called suspension bridges, covered in this article, there are other types of suspension bridges . The type covered here has cables suspended between towers , with vertical suspender cables that transfer the live and dead loads of

2232-522: The failure of a few flawed strands in the hundreds used pose very little threat of failure, whereas a single bad link or eyebar can cause failure of an entire bridge. (The failure of a single eyebar was found to be the cause of the collapse of the Silver Bridge over the Ohio River .) Another reason is that as spans increased, engineers were unable to lift larger chains into position, whereas wire strand cables can be formulated one by one in mid-air from

2294-459: The foundations and pillars consumed 14,250 m³ of concrete. The two towers rise 74 metres from sea level, and the central span is 43 metres tall. From the beginning, the funding process was complicated. The first bank that had lent to the Catarina government failed. Thus, a new loan had to be obtained delaying the works. In addition, a manoeuvre of the U.S. bankers arranging the financing made

2356-432: The highway, which may be supported by suspender cables or their own trusswork . In cases where trusswork supports the spans, there will be very little arc in the outboard main cables. The earliest suspension bridges were ropes slung across a chasm, with a deck possibly at the same level or hung below the ropes such that the rope had a catenary shape. The Tibetan siddha and bridge-builder Thangtong Gyalpo originated

2418-513: The installation of scenic lighting. Initially, only pedestrians and cyclists were able to cross the bridge, but in January 2020, buses and emergency vehicles were allowed to begin crossing. In March, the bridge was opened to all traffic. Suspension bridge A suspension bridge is a type of bridge in which the deck is hung below suspension cables on vertical suspenders. The first modern examples of this type of bridge were built in

2480-408: The island and the mainland, Luz wanted to build the bridge to strengthen the position of Florianópolis as the state capital. At the time, other cities in the state considered the island to be too remote to be the administrative and political centre and consequently there was a movement to transfer the capital to Lages . The bridge was designed by the firm of Robinson & Steinman , and was built by

2542-529: The island to the mainland, the Hercílio Luz Bridge was closed in 1982 on safety concerns. It reopened again on March 15, 1988, to pedestrian traffic, bicycles, motorcycles and horse-drawn vehicles only. It closed completely on July 4, 1991, after a report analyzing the feasibility of reopening the bridge to vehicular traffic was presented in February 1990. In 1997 the landmark bridge was declared

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2604-433: The joining members. Issues occur for the following reasons: A bar may not be made properly due to bad casting, if steel, or not being hammered properly, if iron. This error is evident in points where the head has snapped off from the bar or the head has cracked across from a pin hole to the exterior side. Eye bars when placed as supports in bridges are not layered enough. Consider the catastrophe of Silver Bridge , this

2666-446: The laser, water-jet cutting utilizes a cutting machine but uses for the force of water to cut through the steel. Using water creates smoothed near finished cuts lowering production time. Eyebars were created during the early 1900s where the cost of steel was high. The creation of the eyebar provided a simple solution to lessening the amount of steel needed in a bridge. Using a pin and eye method less stress would theoretically be placed on

2728-534: The live loads. In an underspanned suspension bridge, also called under-deck cable-stayed bridge, the main cables hang entirely below the bridge deck, but are still anchored into the ground in a similar way to the conventional type. Very few bridges of this nature have been built, as the deck is inherently less stable than when suspended below the cables. Examples include the Pont des Bergues of 1834 designed by Guillaume Henri Dufour ; James Smith's Micklewood Bridge; and

2790-404: The mainland. It was closed to the public on May 13, 1991, and reopened after complete restoration on December 30, 2019. The bridge was commissioned by Hercílio Luz , then governor of the state of Santa Catarina , to be the first permanent link between the island and the mainland. In addition to benefiting the then 40,000 residents of Florianópolis that were dependent on ferries to cross between

2852-639: The modern method was Joseph Chaley 's Grand Pont Suspendu in Fribourg , in 1834. In the United States, the first major wire-cable suspension bridge was the Wire Bridge at Fairmount in Philadelphia, Pennsylvania. Designed by Charles Ellet Jr. and completed in 1842, it had a span of 109 m. Ellet's Niagara Falls suspension bridge (1847–48) was abandoned before completion. It was used as scaffolding for John A. Roebling 's double decker railroad and carriage bridge (1855). The Otto Beit Bridge (1938–1939)

2914-406: The pillars to deck-level supports, and further continue to connections with anchors in the ground. The roadway is supported by vertical suspender cables or rods, called hangers. In some circumstances, the towers may sit on a bluff or canyon edge where the road may proceed directly to the main span. Otherwise, the bridge will typically have two smaller spans, running between either pair of pillars and

2976-456: The production of steel items such as eyebars from prefabricated steel plates : A strong laser is used to accurately cut a programmed design from steel. This method is quick and reduces waste, but also requires additional sanding and finishing before use. Oxygen gas is funneled past an electrode creates an arc, which can be channeled down into steel allowing the metal to be cut. This method for cutting only works on conductive metals. Similar to

3038-413: The railing and the walking layer of Gyalpo's bridges used wires. The stress points that carried the screed were reinforced by the iron chains. Before the use of iron chains it is thought that Gyalpo used ropes from twisted willows or yak skins. He may have also used tightly bound cloth. The Inca used rope bridges , documented as early as 1615. It is not known when they were first made. Queshuachaca

3100-612: The roadbed, particularly owing to the unfavorable effects of using plate girders, discovered from the Tacoma Narrows Bridge (1940) bridge collapse. In the 1960s, developments in bridge aerodynamics allowed the re-introduction of plate structures as shallow box girders , first seen on the Severn bridge , built 1961–1966. In the picture of the Yichang Bridge , note the very sharp entry edge and sloping undergirders in

3162-411: The state government confirmed the reopening of traffic on the bridge, which occurred on 30 December 2019. On that day, more than 200,000 people attended the event celebrating its reopening, with the main attraction of the celebration being bungee jumping off of the bridge. The end of construction, however, will occur in 2020, with the removal of auxiliary structures over the central bridge span, alongside

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3224-409: The state of Santa Catarina liable for debts of the failed institution. In the end, the cost reached 14.478 trillion reis , ten times the original estimate and almost double the state budget at the time. The repayment of loans, made by U.S. banks, was completed in 1978, more than 50 years after the inauguration of the bridge. With two other bridges (Colombo Sales Bridge and Pedro Ivo Bridge) now linking

3286-401: The suspension bridge shown. This enables this type of construction to be used without the danger of vortex shedding and consequent aeroelastic effects, such as those that destroyed the original Tacoma Narrows bridge. Three kinds of forces operate on any bridge: the dead load, the live load, and the dynamic load. Dead load refers to the weight of the bridge itself. Like any other structure,

3348-514: The ten bridges with the longest spans, followed by the length of the span and the year the bridge opened for traffic: (Chronological) Broughton Suspension Bridge (England) was an iron chain bridge built in 1826. One of Europe's first suspension bridges, it collapsed in 1831 due to mechanical resonance induced by troops marching in step. As a result of the incident, the British Army issued an order that troops should "break step" when crossing

3410-458: The time of the assembly. Eyebars are used in portions of pin-jointed trusses where it can be established by engineering procedures that the bar will not be imposed with any stress other than tension under all expected conditions. Eyebars are used to supplement roof truss framing supports made of wood or metal. They are placed as the struts for the truss, located next to the king joist. Eyebar links have long been used in suspension bridges with

3472-489: 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 the towers. By design, all static horizontal forces of 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

3534-568: The use of iron chains in his version of simple suspension bridges . In 1433, Gyalpo built eight bridges in eastern Bhutan . The last surviving chain-linked bridge of Gyalpo's was the Thangtong Gyalpo Bridge in Duksum en route to Trashi Yangtse , which was finally washed away in 2004. Gyalpo's iron chain bridges did not include a suspended-deck bridge , which is the standard on all modern suspension bridges today. Instead, both

3596-423: The weight of the cables is small compared to the weight of the deck. One can see the shape from the constant increase of the gradient of the cable with linear (deck) distance, this increase in gradient at each connection with the deck providing a net upward support force. Combined with the relatively simple constraints placed upon the actual deck, that makes the suspension bridge much simpler to design and analyze than

3658-482: The wires to be looped over the eye, rather than requiring threading through a closed eye. The bars may be fabricated with pin holes that are slightly undersized. If so, these are then reamed in the field. This field reaming ensures that stresses will be uniformly distributed among the several bars forming the truss element or the chain link. Corrosion resistant treatment in the form of grease, white or red lead oil paste, or other water-excluding material may be added at

3720-414: Was an instance where only 2 eyebars were paired together as supports in the chain. It was more common practice to use 4 eye bars pinned together in the instance where one eyebar failed 3 more would be able to split the load rather than just the single eyebar left. In the case of Silver bridge the remaining eye bar also broke which caused the bridge to collapse. Like all metal, steel wears down over time. As

3782-661: Was built between 1829 and 1832, replacing a wooden bridge further downstream which collapsed in 1828. It is the only suspension bridge across the non-tidal Thames. The Széchenyi Chain Bridge , (designed in 1840, opened in 1849), spanning the River Danube in Budapest, was also designed by William Clark and it is a larger-scale version of Marlow Bridge. An interesting variation is Thornewill and Warham 's Ferry Bridge in Burton-on-Trent , Staffordshire (1889), where

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3844-404: Was the first modern suspension bridge outside the United States built with parallel wire cables. Two towers/pillars, two suspension cables, four suspension cable anchors, multiple suspender cables, the bridge deck. The main cables of a suspension bridge will form a catenary when hanging under their own weight only. When supporting the deck, the cables will instead form a parabola , assuming

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