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41-556: The Chenab Rail Bridge is a steel and concrete arch bridge carrying a single-track railway line, located between Bakkal and Kauri in the Reasi district of the Jammu Division of Jammu and Kashmir , India. The bridge spans the Chenab River at a height of 359 m (1,178 ft) above the river, making it the world's highest rail bridge and the world's highest arch bridge . The bridge

82-505: 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

123-458: 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

164-447: 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 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

205-448: 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)

246-415: 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

287-430: 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

328-428: 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

369-432: 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

410-628: 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 the Etruscans and ancient Greeks , the Romans were – as with

451-402: 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

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492-629: 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 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

533-540: The Chenab Rail Bridge was designed as a large span single arch steel bridge with approach viaducts on either side. The arch is two-ribbed, fabricated from large steel trusses. The chords of the trusses are sealed steel boxes, internally stiffened and filled with concrete to assist in controlling wind-induced forces on the bridge. Another advantage of concrete filling is that internal painting will not be required. The number of bearings has been minimized, particularly on

574-605: The Indian union territory of Jammu and Kashmir between the towns of Udhampur near Jammu and Baramulla on the northwestern edge of the Kashmir Valley . This project was declared a national project in 2004. It is directed by the Northern Railway. The extraordinary challenge lies in a large number of tunnels (totaling 63 km in length) and bridges (7.5 km) to be implemented in highly rugged and mountainous terrain, with

615-575: The USBRL project, which encompasses the 48.1 km Banihal-Sangaldan section. The Chenab Rail Bridge in Reasi district will soon see trains running on it. In June 2024, the first full trial run on the bridge happened. Key technical data of the bridge include: This makes the Chenab Rail Bridge: Northern Railway has undertaken the megaproject of constructing a new railway line across

656-436: 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

697-761: 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

738-594: The approach viaduct, through the use of continuous construction. This is advantageous, as it reduces the maintenance and inspection efforts, and improves the riding quality. The viaduct piers are of concrete, while the piers near the arch are Indian construction standards such as the Indian Railway Standards (IRS), the Indian Road Congress (IRC) and the Indian Standards (IS) were found inadequate for

779-416: 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

820-400: 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

861-422: 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

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902-615: 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

943-414: 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

984-588: The difficult Himalayan geology. The most difficult part is believed to be the crossing of the deep gorge of the Chenab River, near Salal Hydro Power Dam, by the Chenab Bridge. The engineering marvel lies in the seismic zone IV, and can withstand earthquakes up to a magnitude of 8 on the Richter scale , high-intensity blasts, and winds up to speeds of 260 kilometre per hour. Another, smaller, arch bridge proposed on

1025-550: 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

1066-492: 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

1107-553: The help of IISc Bangalore . Major construction decisions were taken by Konkan Railway Corporation . The Defence Research and Development Organisation (DRDO) helped in the design of the bridge, making it blast-proof using special steel. The erection scheme for the bridge is a project in itself. Two pylons (about 130 m and 100 m high) were erected on either side of the river, and two auxiliary self-propelled cable cranes (capacity of 20 tonnes each) were used to tow temporary auxiliary ropes across these pylons. The ropes were used to support

1148-443: 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

1189-627: The large spans of the Chenab Bridge. For example, the Indian Railway Standards (IRS) is primarily intended for simply supported bridges with spans up to 100m (although these have been successfully used for higher spans up to 154m). The spans for the Chenab Rail Bridge greatly exceed this limit, and are continuous. Therefore, to assure a safe design, Indian national standards have been supplemented with International standards such as British Standards (BS), International Union of Railways (UIC) and Euro. Also, many global experts with versatile and relevant experience, have been involved in order to facilitate making

1230-543: The new railway line was the 657 m (2,156 ft) long, 189 m (620 ft) high Anji Khad Bridge between Katra and Reasi over the Chenab river tributary river. This proposal was abandoned by the railway due to the specific geology of the location and a cable-stayed bridge is proposed, which will be Indian Railways first cable-stayed bridge. After many deliberations, taking into account aesthetics, economy, and availability of local expertise and construction materials,

1271-471: 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

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1312-429: The partly finished arch parts. After arch completion, the trusses will be added, finally the girder will be constructed as a horizontal sliding type platform. Regular painting of large bridges is an intimidating task; hence, a painting scheme was developed, having renewal of over 15 years, compared to approx. 5 to 7 years in most other Indian railway bridges. Arch bridge Possibly the oldest existing arch bridge

1353-471: The project a success. Following are some of the design considerations taken into account: The quality aspect has been emphasized, as the quantum of fabrication and welding is colossal. Mostly indigenous material compliant to IS codes has been planned to be used, whereas for the design, international codes have been referred, which means the Quality Control work is still difficult. The Chenab Rail Bridge

1394-615: 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 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

1435-451: 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,

1476-565: The vault and the dome." Afcons Infrastructure Afcons Infrastructure Limited is an Indian multinational construction and engineering company based in Mumbai . The company is involved in infrastructure EPC projects such as bridges, flyovers, metros , railway lines, tunnels, highways, ports and marine works, barrages , and oil and gas structures. It has been a part of the Shapoorji Pallonji Group since 2000. The company

1517-402: 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

1558-679: Was founded in 1959 as Rodio Hazarat & Co, a joint venture between Rodio Foundation Engineering of Switzerland and Hazarat & Co of India. In the initial years, the company undertook foundation work of office buildings in Mumbai's then-business district Nariman Point . In 1976, the Swiss partner exited the joint venture by selling its stake to an employees-led consortium, owing to the Foreign Exchange Regulation Act legislation passed in 1973 which affected its business viability. The company

1599-753: Was fully completed and was inaugurated in August 2022. It is built between the Sangaldan Railway Station and the Reasi Railway Station . In November 2017, the base supports were declared completed allowing for the start of the construction of the main arch. In April 2021, the Chenab Rail Bridge's arch was completed and the overall bridge was completed in August 2022. It was expected to open to rail traffic by December 2023 or by January/February 2024 but has been rescheduled to July. On February 20, 2024, Indian prime minister Narendra Modi officially launched

1640-552: Was originally intended to be completed in December 2009. However, in September 2008, the project was halted due to fears over the bridge's stability and safety. Work on the bridge restarted in 2010, with the plan to complete it in 2015. The design and construction was awarded to Afcons Infrastructure , a part of the Shapoorji Pallonji Group , the third-largest construction group in India, with

1681-400: Was renamed as Asia Foundations and Construction in the same year. The company later expanded its business interests beyond foundation engineering to include marine construction (jetties, docks and harbours) and transportation works (roads and bridges). In 1997, the company was renamed to Afcons Infrastructure. In the 1990s, the company raised debt funding from ICICI , which later converted

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