90-567: Angers Bridge , also called the Basse-Chaîne Bridge , was a suspension bridge over the Maine River in Angers , France. It was designed by Joseph Chaley and Bordillon, and built between 1836 and 1839. The bridge collapsed on 16 April 1850, while a battalion of French soldiers were marching across it, killing over 200. The bridge spanned 102 m (335 ft), with two wire cables carrying
180-596: A bridge-restaurant which is a bridge built to serve as a restaurant. Other suspension bridge towers carry transmission antennas. Conservationists use wildlife overpasses to reduce habitat fragmentation and animal-vehicle collisions. The first animal bridges sprung up in France in the 1950s, and these types of bridges are now used worldwide to protect both large and small wildlife. Bridges are subject to unplanned uses as well. The areas underneath some bridges have become makeshift shelters and homes to homeless people, and
270-410: 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
360-533: 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 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
450-492: 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
540-520: A bridge is to be designed, standards authorities specify simplified notional load models, notably HL-93, intended to give the same load effects as the characteristic maximum values. The Eurocode is an example of a standard for bridge traffic loading that was developed in this way. Most bridge standards are only applicable for short and medium spans - for example, the Eurocode is only applicable for loaded lengths up to 200 m. Longer spans are dealt with on
630-468: 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
720-757: 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
810-471: A case-by-case basis. It is generally accepted that the intensity of load reduces as span increases because the probability of many trucks being closely spaced and extremely heavy reduces as the number of trucks involved increases. It is also generally assumed that short spans are governed by a small number of trucks traveling at high speed, with an allowance for dynamics. Longer spans on the other hand, are governed by congested traffic and no allowance for dynamics
900-480: A combination of structural health monitoring and testing. This is regulated in country-specific engineer standards and includes an ongoing monitoring every three to six months, a simple test or inspection every two to three years and a major inspection every six to ten years. In Europe, the cost of maintenance is considerable and is higher in some countries than spending on new bridges. The lifetime of welded steel bridges can be significantly extended by aftertreatment of
990-433: A deck 7.2 m (24 ft) wide. Its towers consisted of cast iron columns 5.47 m (17.9 ft) tall. Soldiers stationed in the region frequently used the bridge, and two battalions of the same regiment had crossed earlier that day. The third battalion arrived during a powerful thunderstorm when the wind was making the bridge oscillate. When the soldiers began to cross, their bodies acted as sails, further catching
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#17330935829151080-399: A different site, and re-used. They are important in military engineering and are also used to carry traffic while an old bridge is being rebuilt. Movable bridges are designed to move out of the way of boats or other kinds of traffic, which would otherwise be too tall to fit. These are generally electrically powered. The Tank bridge transporter (TBT) has the same cross-country performance as
1170-594: A few will predominate. The separation of forces and moments may be quite clear. In a suspension or cable-stayed bridge , the elements in tension are distinct in shape and placement. In other cases the forces may be distributed among a large number of members, as in a truss. The world's longest beam bridge is Lake Pontchartrain Causeway in southern Louisiana in the United States, at 23.83 miles (38.35 km), with individual spans of 56 feet (17 m). Beam bridges are
1260-461: 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 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
1350-403: 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
1440-401: 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 the deck below, upon which traffic crosses. This arrangement allows
1530-460: 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. Bridge A bridge is a structure built to span a physical obstacle (such as a body of water , valley , road, or railway) without blocking the path underneath. It is constructed for the purpose of providing passage over the obstacle, which
1620-641: 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
1710-460: A second later, and the right-bank end of the deck fell, making the deck slope very steep and throwing soldiers into the river. Many of those who fell were saved by their fellow soldiers who had not yet crossed and by residents of Angers who came to the rescue, but a total of 226 people died. The failure was attributed to dynamic load due to the storm and the soldiers, particularly as they seem to have been somewhat in step, combined with corrosion of
1800-538: 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
1890-553: A simple type of suspension bridge , were used by the Inca civilization in the Andes mountains of South America, just prior to European colonization in the 16th century. The Ashanti built bridges over streams and rivers . They were constructed by pounding four large forked tree trunks into the stream bed, placing beams along these forked pillars, then positioning cross-beams that were finally covered with four to six inches of dirt. During
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#17330935829151980-578: A span of 552 m (1,811 ft). The bridge was opened 29 April 2009, in Chongqing , China. The longest suspension bridge in the world is the 4,608 m (15,118 ft) 1915 Çanakkale Bridge in Turkey. The longest cable-stayed bridge since 2012 is the 1,104 m (3,622 ft) Russky Bridge in Vladivostok , Russia. Some Engineers sub-divide 'beam' bridges into slab, beam-and-slab and box girder on
2070-732: A stream. Often in palaces, a bridge will be built over an artificial waterway as symbolic of a passage to an important place or state of mind. A set of five bridges cross a sinuous waterway in an important courtyard of the Forbidden City in Beijing, China. The central bridge was reserved exclusively for the use of the Emperor and Empress, with their attendants. The estimated life of bridges varies between 25 and 80 years depending on location and material. Bridges may age hundred years with proper maintenance and rehabilitation. Bridge maintenance consisting of
2160-479: A tank even when fully loaded. It can deploy, drop off and load bridges independently, but it cannot recover them. Double-decked (or double-decker) bridges have two levels, such as the George Washington Bridge , connecting New York City to Bergen County , New Jersey , US, as the world's busiest bridge, carrying 102 million vehicles annually; truss work between the roadway levels provided stiffness to
2250-499: 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
2340-456: Is a bridge that carries water, resembling a viaduct, which is a bridge that connects points of equal height. A road-rail bridge carries both road and rail traffic. Overway is a term for a bridge that separates incompatible intersecting traffic, especially road and rail. Some bridges accommodate other purposes, such as the tower of Nový Most Bridge in Bratislava , which features a restaurant, or
2430-574: Is an early example of a double-decked bridge. The upper level carries a railway, and the lower level is used for road traffic. Other examples include Britannia Bridge over the Menai Strait and Craigavon Bridge in Derry, Northern Ireland. The Oresund Bridge between Copenhagen and Malmö consists of a four-lane highway on the upper level and a pair of railway tracks at the lower level. Tower Bridge in London
2520-485: Is different example of a double-decked bridge, with the central section consisting of a low-level bascule span and a high-level footbridge . A viaduct is made up of multiple bridges connected into one longer structure. The longest and some of the highest bridges are viaducts, such as the Lake Pontchartrain Causeway and Millau Viaduct . A multi-way bridge has three or more separate spans which meet near
2610-417: Is led by architects, bridges are usually designed by engineers. This follows from the importance of the engineering requirements; namely spanning the obstacle and having the durability to survive, with minimal maintenance, in an aggressive outdoor environment. Bridges are first analysed; the bending moment and shear force distributions are calculated due to the applied loads. For this, the finite element method
2700-540: Is needed. Calculating the loading due to congested traffic remains a challenge as there is a paucity of data on inter-vehicle gaps, both within-lane and inter-lane, in congested conditions. Weigh-in-Motion (WIM) systems provide data on inter-vehicle gaps but only operate well in free flowing traffic conditions. Some authors have used cameras to measure gaps and vehicle lengths in jammed situations and have inferred weights from lengths using WIM data. Others have used microsimulation to generate typical clusters of vehicles on
2790-737: Is the most popular. The analysis can be one-, two-, or three-dimensional. For the majority of bridges, a two-dimensional plate model (often with stiffening beams) is sufficient or an upstand finite element model. On completion of the analysis, the bridge is designed to resist the applied bending moments and shear forces, section sizes are selected with sufficient capacity to resist the stresses. Many bridges are made of prestressed concrete which has good durability properties, either by pre-tensioning of beams prior to installation or post-tensioning on site. In most countries, bridges, like other structures, are designed according to Load and Resistance Factor Design (LRFD) principles. In simple terms, this means that
Angers Bridge - Misplaced Pages Continue
2880-594: Is usually something that is otherwise difficult or impossible to cross. There are many different designs of bridges, each serving a particular purpose and applicable to different situations. Designs of bridges vary depending on factors such as the function of the bridge, the nature of the terrain where the bridge is constructed and anchored, the material used to make it, and the funds available to build it. The earliest bridges were likely made with fallen trees and stepping stones . The Neolithic people built boardwalk bridges across marshland. The Arkadiko Bridge , dating from
2970-806: 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 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
3060-618: The Hellenistic era can be found in the Peloponnese. The greatest bridge builders of antiquity were the ancient Romans . The Romans built arch bridges and aqueducts that could stand in conditions that would damage or destroy earlier designs, some of which still stand today. An example is the Alcántara Bridge , built over the river Tagus , in Spain. The Romans also used cement, which reduced
3150-797: 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
3240-833: The University of Minnesota ). Likewise, in Toronto , the Prince Edward Viaduct has five lanes of motor traffic, bicycle lanes, and sidewalks on its upper deck; and a pair of tracks for the Bloor–Danforth subway line on its lower deck. The western span of the San Francisco–Oakland Bay Bridge also has two levels. Robert Stephenson 's High Level Bridge across the River Tyne in Newcastle upon Tyne , completed in 1849,
3330-495: The river Severn . With the Industrial Revolution in the 19th century, truss systems of wrought iron were developed for larger bridges, but iron does not have the tensile strength to support large loads. With the advent of steel, which has a high tensile strength, much larger bridges were built, many using the ideas of Gustave Eiffel . In Canada and the United States, numerous timber covered bridges were built in
3420-521: The 13th century BC, in the Peloponnese is one of the oldest arch bridges in existence and use. The Oxford English Dictionary traces the origin of the word bridge to an Old English word brycg , of the same meaning. The Oxford English Dictionary also notes that there is some suggestion that the word can be traced directly back to Proto-Indo-European *bʰrēw-. However, they also note that "this poses semantic problems." The origin of
3510-511: The 18th century, there were many innovations in the design of timber bridges by Hans Ulrich Grubenmann , Johannes Grubenmann , as well as others. The first book on bridge engineering was written by Hubert Gautier in 1716. A major breakthrough in bridge technology came with the erection of the Iron Bridge in Shropshire, England in 1779. It used cast iron for the first time as arches to cross
3600-537: The Millennium Bridge was corrected during the next two years. 47°28′14″N 00°33′50″W / 47.47056°N 0.56389°W / 47.47056; -0.56389 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 the early 1800s. Simple suspension bridges , which lack vertical suspenders, have
3690-638: 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 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
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3780-542: 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
3870-543: 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)
3960-568: The anchors for the main cables. The cable anchorages at Angers were found to be highly vulnerable, as they were surrounded by cement, which was believed to rustproof them for the indefinite future. However, the wire strands separated from their cement surrounds. This allowed water to penetrate and corrode the wires. The disaster led France to abandon suspension bridges until 1870. There had been similar failures elsewhere, such as that at Great Yarmouth in England in May 1845, when 79 people were killed by
4050-610: The appearance of the bridge can have great importance. Often, this is the case with a large bridge that serves as an entrance to a city, or crosses over a main harbor entrance. These are sometimes known as signature bridges. Designers of bridges in parks and along parkways often place more importance on aesthetics, as well. Examples include the stone-faced bridges along the Taconic State Parkway in New York. Bridges are typically more aesthetically pleasing if they are simple in shape,
4140-613: The attention of the general public in the 1990s by the novel, movie and play The Bridges of Madison County . In 1927, welding pioneer Stefan Bryła designed the first welded road bridge in the world, the Maurzyce Bridge which was later built across the river Słudwia at Maurzyce near Łowicz , Poland in 1929. In 1995, the American Welding Society presented the Historic Welded Structure Award for
4230-596: The basis of their cross-section. A slab can be solid or voided (though this is no longer favored for inspectability reasons) while beam-and-slab consists of concrete or steel girders connected by a concrete slab. A box-girder cross-section consists of a single-cell or multi-cellular box. In recent years, integral bridge construction has also become popular. Most bridges are fixed bridges, meaning they have no moving parts and stay in one place until they fail or are demolished. Temporary bridges, such as Bailey bridges , are designed to be assembled, taken apart, transported to
4320-432: 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
4410-437: The bridge to Poland. Bridges can be categorized in several different ways. Common categories include the type of structural elements used, by what they carry, whether they are fixed or movable, and by the materials used. Bridges may be classified by how the actions of tension , compression , bending , torsion and shear are distributed through their structure. Most bridges will employ all of these to some degree, but only
4500-439: The center of the bridge. Multi-way bridges with only three spans appear as a "T" or "Y" when viewed from above. Multi-way bridges are extremely rare. The Tridge , Margaret Bridge , and Zanesville Y-Bridge are examples. A bridge can be categorized by what it is designed to carry, such as trains, pedestrian or road traffic ( road bridge ), a pipeline ( Pipe bridge ) or waterway for water transport or barge traffic. An aqueduct
4590-519: 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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#17330935829154680-517: 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
4770-467: The deck is thinner in proportion to its span, the lines of the structure are continuous, and the shapes of the structural elements reflect the forces acting on them. To create a beautiful image, some bridges are built much taller than necessary. This type, often found in east-Asian style gardens, is called a Moon bridge , evoking a rising full moon. Other garden bridges may cross only a dry bed of stream-washed pebbles, intended only to convey an impression of
4860-437: 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 the pillars to deck-level supports, and further continue to connections with anchors in
4950-571: 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
5040-644: The failure of the Tacoma Narrows Bridge in 1940. However, the Angers bridge failure caused by far the greatest number of casualties. When the London Thames Millennium Bridge was opened in 2000, the motion of pedestrians caused it to vibrate, and they fell into step with the vibrations, increasing them. This same mechanism may have increased the vibrations of the Angers Bridge. The problem at
5130-464: The fall of the main deck. The fall of the Angers bridge raised serious questions about the integrity of suspension bridges, and some engineers (such as John A. Roebling ) used reinforced decks in future structures such as the Brooklyn Bridge . Louis Vicat reported in 1853 on the problems with the anchorages, and all similar bridges in France had to be carefully inspected. A new bridge was built on
5220-595: The first human-made bridges with significant span were probably intentionally felled trees. Among the oldest timber bridges is the Holzbrücke Rapperswil-Hurden bridge that crossed upper Lake Zürich in Switzerland; prehistoric timber pilings discovered to the west of the Seedamm causeway date back to 1523 BC. The first wooden footbridge there led across Lake Zürich; it was reconstructed several times through
5310-434: 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 the highway, which may be supported by suspender cables or their own trusswork . In cases where trusswork supports
5400-748: The late 1700s to the late 1800s, reminiscent of earlier designs in Germany and Switzerland. Some covered bridges were also built in Asia. In later years, some were partly made of stone or metal but the trusses were usually still made of wood; in the United States, there were three styles of trusses, the Queen Post, the Burr Arch and the Town Lattice. Hundreds of these structures still stand in North America. They were brought to
5490-464: The late 2nd century AD, when the Roman Empire built a 6-metre-wide (20 ft) wooden bridge to carry transport across the lake. Between 1358 and 1360, Rudolf IV, Duke of Austria , built a 'new' wooden bridge across the lake that was used until 1878; it was approximately 1,450 metres (4,760 ft) long and 4 metres (13 ft) wide. On 6 April 2001, a reconstruction of the original wooden footbridge
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#17330935829155580-530: 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
5670-427: The load is factored up by a factor greater than unity, while the resistance or capacity of the structure is factored down, by a factor less than unity. The effect of the factored load (stress, bending moment) should be less than the factored resistance to that effect. Both of these factors allow for uncertainty and are greater when the uncertainty is greater. Most bridges are utilitarian in appearance, but in some cases,
5760-629: The past, these load models were agreed by standard drafting committees of experts but today, this situation is changing. It is now possible to measure the components of bridge traffic load, to weigh trucks, using weigh-in-motion (WIM) technologies. With extensive WIM databases, it is possible to calculate the maximum expected load effect in the specified return period. This is an active area of research, addressing issues of opposing direction lanes, side-by-side (same direction) lanes, traffic growth, permit/non-permit vehicles and long-span bridges (see below). Rather than repeat this complex process every time
5850-468: The principles of Load and Resistance Factor Design . Before factoring to allow for uncertainty, the load effect is generally considered to be the maximum characteristic value in a specified return period . Notably, in Europe, it is the maximum value expected in 1000 years. Bridge standards generally include a load model, deemed to represent the characteristic maximum load to be expected in the return period. In
5940-529: 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
6030-742: The roadways and reduced movement of the upper level when the lower level was installed three decades after the upper level. The Tsing Ma Bridge and Kap Shui Mun Bridge in Hong Kong have six lanes on their upper decks, and on their lower decks there are two lanes and a pair of tracks for MTR metro trains. Some double-decked bridges only use one level for street traffic; the Washington Avenue Bridge in Minneapolis reserves its lower level for automobile and light rail traffic and its upper level for pedestrian and bicycle traffic (predominantly students at
6120-451: The same cadence, causing resonance . In any case, the oscillation increased. At a time when the bridge was covered with 483 soldiers and four other people (although the police had prevented many curiosity seekers from joining the march), the upstream anchoring cable on the right bank broke in its concrete mooring, three to four meters underground, with a noise like "a badly done volley from a firing squad". The adjacent downstream cable broke
6210-590: The same site in 1960, using reinforced concrete beams. The Angers bridge was not the first suspension bridge to collapse. Previous failures included the Dryburgh Abbey Bridge in 1818 and The Royal Suspension Chain Pier in Brighton in 1836. The Menai Suspension Bridge was damaged by wind in 1825, 1836 and 1839. The Broughton Suspension Bridge had collapsed in 1831 when soldiers marched over it in step. Subsequent spectacular suspension bridge collapses caused by wind include
6300-698: The same year, has the span of 90 m (295 ft) and crosses the valley of the Syrabach River. The difference between the two is that the Solkan Bridge was built from stone blocks, whereas the Friedensbrücke was built from a mixture of crushed stone and cement mortar. The world's largest arch bridge is the Chaotianmen Bridge over the Yangtze River with a length of 1,741 m (5,712 ft) and
6390-430: The simplest and oldest type of bridge in use today, and are a popular type. Some cantilever bridges also have a smaller beam connecting the two cantilevers, for extra strength. The largest cantilever bridge is the 549-metre (1,801 ft) Quebec Bridge in Quebec, Canada. With the span of 220 metres (720 ft), the Solkan Bridge over the Soča River at Solkan in Slovenia is the second-largest stone bridge in
6480-496: 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 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
6570-401: 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,
6660-501: 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 the modern method was Joseph Chaley 's Grand Pont Suspendu in Fribourg , in 1834. In
6750-508: 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
6840-790: The time of the Warring States period , the oldest surviving stone bridge in China is the Zhaozhou Bridge , built from 595 to 605 AD during the Sui dynasty . This bridge is also historically significant as it is the world's oldest open-spandrel stone segmental arch bridge. European segmental arch bridges date back to at least the Alconétar Bridge (approximately 2nd century AD), while the enormous Roman era Trajan's Bridge (105 AD) featured open-spandrel segmental arches in wooden construction. Rope bridges ,
6930-489: 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
7020-740: The undertimbers of bridges all around the world are spots of prevalent graffiti. Some bridges attract people attempting suicide, and become known as suicide bridges . The materials used to build the structure are also used to categorize bridges. Until the end of the 18th century, bridges were made out of timber, stone and masonry. Modern bridges are currently built in concrete, steel, fiber reinforced polymers (FRP), stainless steel or combinations of those materials. Living bridges have been constructed of live plants such as Ficus elastica tree roots in India and wisteria vines in Japan. Unlike buildings whose design
7110-448: 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 is considered the last remaining Inca rope bridge and is rebuilt annually. The first iron chain suspension bridge in the Western world
7200-507: The variation of strength found in natural stone. One type of cement, called pozzolana , consisted of water, lime , sand, and volcanic rock . Brick and mortar bridges were built after the Roman era , as the technology for cement was lost (then later rediscovered). In India, the Arthashastra treatise by Kautilya mentions the construction of dams and bridges. A Mauryan bridge near Girnar
7290-423: 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
7380-433: The weld transitions . This results in a potential high benefit, using existing bridges far beyond the planned lifetime. While the response of a bridge to the applied loading is well understood, the applied traffic loading itself is still the subject of research. This is a statistical problem as loading is highly variable, particularly for road bridges. Load Effects in bridges (stresses, bending moments) are designed for using
7470-402: The wind. Survivors reported that they had been walking as if drunk and could barely keep themselves from falling, first to one side and then to the other. As usual in crossing that bridge, the soldiers had been ordered to break step and to space themselves farther apart than normal. However, their efforts to match the swaying and keep their balance may have caused them to involuntarily march with
7560-582: The word for the card game of the same name is unknown. The simplest and earliest types of bridges were stepping stones . Neolithic people also built a form of boardwalk across marshes ; examples of such bridges include the Sweet Track and the Post Track in England, approximately 6000 years old. Ancient people would also have used log bridges consisting of logs that fell naturally or were intentionally felled or placed across streams. Some of
7650-448: The world and the longest railroad stone bridge. It was completed in 1905. Its arch, which was constructed from over 5,000 tonnes (4,900 long tons; 5,500 short tons) of stone blocks in just 18 days, is the second-largest stone arch in the world, surpassed only by the Friedensbrücke (Syratalviadukt) in Plauen , and the largest railroad stone arch. The arch of the Friedensbrücke, which was built in
7740-519: Was opened; it is also the longest wooden bridge in Switzerland. The Arkadiko Bridge is one of four Mycenaean corbel arch bridges part of a former network of roads, designed to accommodate chariots , between the fort of Tiryns and town of Epidauros in the Peloponnese , in southern Greece . Dating to the Greek Bronze Age (13th century BC), it is one of the oldest arch bridges still in existence and use. Several intact, arched stone bridges from
7830-510: Was surveyed by James Princep . The bridge was swept away during a flood, and later repaired by Puspagupta, the chief architect of emperor Chandragupta I . The use of stronger bridges using plaited bamboo and iron chain was visible in India by about the 4th century. A number of bridges, both for military and commercial purposes, were constructed by the Mughal administration in India. Although large bridges of wooden construction existed in China at
7920-530: 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 the Philadelphia journal, The Port Folio , in 1810. Early British chain bridges included
8010-529: 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 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
8100-404: 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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