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Union Chain Bridge

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79-525: The Union Chain Bridge or Union Bridge is a suspension bridge that spans the River Tweed between Horncliffe , Northumberland , England and Fishwick , Berwickshire , Scotland. It is four miles (6.4 km) upstream of Berwick-upon-Tweed . When it opened in 1820 it was the longest wrought iron suspension bridge in the world with a span of 449 feet (137 m), and the first vehicular bridge of its type in

158-410: 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

237-456: 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

316-492: 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

395-468: 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

474-757: 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

553-415: A coach pulled by four horses, a penny for an unladen horse and ten pence for a drove of 20 cows. The trustees could call on a portion of the statute duty from the parishes, either as labour or by a cash payment. The trust applied the income to pay for labour and materials to maintain the road. They were also able to mortgage future tolls to raise loans for new structures and for more substantial improvements to

632-521: A disproportionate amount of damage to the road. The rate at which new trusts were created slowed in the early 19th century but the existing trusts were making major investments in highway improvement. The government had been directly involved in the building of military roads in Scotland following a rebellion in 1745, but the first national initiative was a scheme to aid communications with Ireland . Between 1815 and 1826 Thomas Telford undertook

711-683: A fifth of the roads in Britain; the majority being maintained by the parishes. A trust would typically be responsible for about 20 miles (32 km) of highway, although exceptions such as the Exeter Turnpike Trust controlled 147 miles (237 km) of roads radiating from the city. On the Bath Road for instance, a traveller from London to the head of the Thames Valley in Wiltshire would pass through

790-403: 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

869-583: A major reorganization of the existing trusts along the London to Holyhead Road , and the construction of large sections of new road to avoid hindrances, particularly in North Wales. By 1838 the turnpike trusts in England were collecting £1.5 million per year from leasing the collection of tolls but had a cumulative debt of £7 million, mainly as mortgages. Even at its greatest extent, the turnpike system only administered

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948-616: A patent in 1816 for a method of manufacturing chains, followed by a patent titled Construction of a Bridge by the Formation and Uniting of its Component Parts in July 1817. In around 1817, Brown proposed a 1,000 feet (300 m) span bridge over the River Mersey at Runcorn , but this bridge was not built. It is not known why Brown became involved with the Union Bridge project, but agreed to take on

1027-507: 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. Turnpike trust Turnpike trusts were bodies set up by individual Acts of Parliament , with powers to collect road tolls for maintaining the principal roads in Britain from the 17th but especially during the 18th and 19th centuries. At

1106-641: 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

1185-575: A restoration project that was then expected to cost £5 million. Between then and August 2020 further pledges were made by both councils, the National Lottery Heritage Fund and Historic England . The work started in October 2020 and was expected to cost £10.5 million and take around 18 months. The chains were cut in March 2021 and the restored bridge was due to re-open in early 2022. In August 2022,

1264-709: A rising volume of traffic, or in building new sections of road. During the first three decades of the 18th century, sections of the main radial roads into London were put under the control of individual turnpike trusts. The pace at which new turnpikes were created picked up in the 1750s as trusts were formed to maintain the cross-routes between the Great Roads radiating from London. Roads leading into some provincial towns, particularly in Western England, were put under single trusts and key roads in Wales were turnpiked. In South Wales,

1343-538: 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

1422-499: 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

1501-550: A trust was ended, there were often great celebrations as the gates were thrown open. The assets of the trust, such as tollhouses, gates and sections of surplus land beside the road were auctioned off to reduce the debt, and mortgagees were paid at whatever rate in the pound the funds would allow. The legacy of the turnpike trust is the network of roads that still form the framework of the main road system in Britain. In addition, many roadside features such as milestones and tollhouses have survived, despite no longer having any function in

1580-639: Is a sandstone pier on the Scottish side, while the English side has a sandstone tower built into the side of the river bluffs that supports the bridges chains. It is this configuration as to why the Scottish side has a straight approach road but across the river, the road turns sharply south due to the river bank's steep sides. It opened on 26 July 1820, with an opening ceremony attended by the celebrated Scottish civil engineer Robert Stevenson among others. Captain Brown tested

1659-627: 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

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1738-410: Is now maintained by the latter. In addition to the 1902 addition of cables, the bridge has been strengthened and refurbished on many occasions. The bridge deck was substantially renewed in 1871, and again in 1974, with the chains reinforced at intervals throughout its life. The bridge was closed to motor vehicles for several months during 2007 due to one of the bridge hangers breaking. In December 2008

1817-797: 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

1896-512: The Pennine Cycleway . Its chains are represented on the Flag of Berwickshire . Before the opening of the Union Bridge, crossing the river at this point involved an 11-mile (18 km) round trip via Berwick downstream or a 20-mile (32 km) trip via Coldstream upstream. ( Ladykirk and Norham Bridge did not open until 1888.) The Tweed was forded in the vicinity of the bridge site, but the route

1975-635: The coming of the railways and then the Local Government Act 1888 gave responsibility for maintaining main roads to county councils and county borough councils. The term "turnpike" originates from the similarity of the gate used to control access to the road, to the barriers once used to defend against attack by cavalry (see cheval de frise ). The turnpike consisted of a row of pikes or bars, each sharpened at one end, and attached to horizontal members which were secured at one end to an upright pole or axle, which could be rotated to open or close

2054-614: The 1870s it was feasible for Parliament to close the trusts progressively without leaving an unacceptable financial burden on local communities. From 1871, all applications for renewal were sent to the Turnpike Trust Commission. This arranged for existing acts to continue, but with the objective of discharging the debt, and returning the roads to local administration, which was by then by highway boards . The Local Government Act 1888 gave responsibility for maintaining main roads to county councils and county borough councils. When

2133-501: The A5) in the 1820s reduced the journey time of the London mail coach from 45 hours to just 27 hours, and the best mail coach speeds rose from 5-6 mph (8–10 km/h) to 9-10 mph (14–16 km/h). McAdam and his sons were employed as general surveyors (consultant engineers) to many of the main turnpike trusts in southern England. They recommended the building of new sections of road to avoid obstructions, eased steep slopes and directed

2212-741: 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

2291-542: 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

2370-525: The United Kingdom. Although work started on the Menai Suspension Bridge earlier, the Union Bridge was completed first. The suspension bridge, which is a Category A listed building in Scotland, is now the oldest to be still carrying road traffic. The bridge is also a Grade I listed building in England and an International Historic Civil Engineering Landmark . It lies on Sustrans Route 1 and

2449-432: 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

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2528-567: The bridge in a curricle towing twelve carts before a crowd of about 700 spectators crossed. Until 1885, tolls were charged for crossing the bridge; the toll cottage on the English side was demolished in 1955. With the abolition of turnpike tolls in 1883, maintenance of the bridge passed to the Tweed Bridges Trust. When the Trust was wound up the bridge became the responsibility of Scottish Borders Council and Northumberland County Council and

2607-510: The bridge was closed to traffic as a result of a landslide. In March 2013 there was a proposal to close the bridge because there was a lack of funds to maintain it. In 2013, the bridge was placed on Historic England 's Heritage at Risk register. In October 2014, local enthusiasts and activists started a campaign to have the bridge fully restored in time for its bicentenary in 2020. In March 2017 Scottish Borders Council and Northumberland County Council agreed to contribute £550,000 each towards

2686-520: The bridge was reported as being "almost complete" and it was reopened on 17 April 2023. Shortly after its restoration, in July 2023, the bridge was designated as a Historic Civil Engineering Landmark by the American Society of Civil Engineers . 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

2765-484: 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

2844-574: 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

2923-519: 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 ,

3002-467: 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

3081-417: 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

3160-418: 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

3239-411: The existing highway. The trusts applied some funds to erecting tollhouses that accommodated the pikeman or toll-collector beside the turnpike gate. Although trusts initially organised the collection of tolls directly, it became common for them to auction a lease to collect tolls. Specialist toll-farmers would make a fixed payment to the trust for the lease and then organise the day-to-day collection of

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3318-571: 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

3397-447: The gate. Pavage grants, originally made for paving the marketplace or streets of towns, began also to be used for maintaining some roads between towns in the 14th century. These grants were made by letters patent , almost invariably for a limited term, presumably the time likely to be required to pay for the required works. Tudor statutes had placed responsibility on each parish vestry to maintain all its roads. This arrangement

3476-425: The highway passed, augment this with tolls from users from outside the parishes and apply the whole to the maintenance of the main highway. This became the pattern for the turnpiking of a growing number of highways, sought by those who wished to improve flow of commerce through their part of a county. The proposal to turnpike a particular section of road was normally a local initiative and a separate Act of Parliament

3555-432: 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

3634-441: The highway. These officers were paid by the trust. Trustees were not paid, though they derived indirect benefits from the better transport, which improved access to markets and led to increases in rental income and trade. The first action of a new trust was to erect turnpike gates at which a fixed toll was charged. The Act gave a maximum toll allowable for each class of vehicle or animal – for instance one shilling and six pence for

3713-495: The jurisdiction of seven trusts, paying a toll at the gates of each. Although a few trusts built new bridges (e.g. at Shillingford over the Thames), most bridges remained a county responsibility. A few bridges were built with private funds and tolls taken at these (e.g., the present Swinford Toll Bridge over the Thames). The quality of early turnpike roads was varied. Although turnpiking did result in some improvement to each highway,

3792-564: The justices in other counties in England and Wales. An example is the first Turnpike Act for Surrey, the Surrey and Sussex Highways Act 1696 ( 8 & 9 Will. 3 . c. 15), during the reign of William III for enhanced repairs between Reigate in Surrey and Crawley in Sussex. The act made provision to erect turnpikes , and appoint toll collectors; also to appoint surveyors, who were authorized by order of

3871-470: The justices to borrow money at five per cent interest, on security of the tolls. The first scheme that had trustees who were not justices was established through a Turnpike Act in 1706 ( 6 Ann. c. 4) for a section of the London- Chester road between Fornhill (near Hockliffe ) and Stony Stratford . The basic principle was that the trustees would manage resources from the several parishes through which

3950-530: 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

4029-413: The local justices of the peace powers to erect toll-gates on a section of the road, between Wadesmill , Hertfordshire; Caxton , Cambridgeshire ; and Stilton , Huntingdonshire for 11 years, the revenues so raised to be used for the maintenance of the road in their jurisdictions ( 15 Cha. 2 . c. 1). The toll-gate erected at Wadesmill was the prototype in England. Parliament then gave similar powers to

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4108-684: 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)

4187-404: The money, leaving themselves with a profit on their operations over a year. The powers of a trust were limited, normally to 21 years, after which it was assumed that the responsibility for the now-improved road would be handed back to the parishes. However, trusts routinely sought new powers before this time limit, usually citing the need to pay off the debts incurred in repairing damage caused by

4266-500: The peak, in the 1830s, over 1,000 trusts administered around 30,000 miles (48,000 km) of turnpike road in England and Wales, taking tolls at almost 8,000 toll-gates and side-bars. During the early 19th century the concept of the turnpike trust was adopted and adapted to manage roads within the British Empire (Ireland, Canada, Australia, New Zealand, India, and South Africa) and in the United States. Turnpikes declined with

4345-406: 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

4424-413: 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

4503-642: The relaying of existing road-beds with carefully graded stones to create a dry, fast-running surface (known as Macadamising ). Coach design improved to take advantage of these better roads and in 1843 the London-to- Exeter mail coach could complete the 170-mile (270-km) journey in 17 hours. The introduction of toll gates had been resented by local communities which had freely used the routes for centuries. Early Acts had given magistrates powers to punish anyone damaging turnpike property, such as defacing milestones, breaking turnpike gates or avoiding tolls. Opposition

4582-463: The renewal acts for the earlier trusts incorporated a growing list of powers and responsibilities. The Kent Roads Act 1743 ( 17 Geo. 2 . c. 4), the Turnpike Roads Act 1766 ( 7 Geo. 3 . c. 40) and the Turnpike Roads Act 1773 ( 13 Geo. 3 . c. 84) made statutory provision for the erection of milestones along the turnpike roads indicating the distance between the main towns on the road. Users of

4661-632: The result was that toll gates were dismantled and the trusts abolished in the six counties of South Wales , their powers being transferred to a roads board for each county. These are incomplete lists of trusts by county. By the early Victorian period toll gates were perceived as an impediment to free trade. The multitude of small trusts were frequently charged with being inefficient in use of resources and potentially suffered from petty corruption. The railway era spelt disaster for most turnpike trusts. Although some trusts in districts not served by railways managed to increase revenue, most did not. In 1829,

4740-447: The road were obliged to follow what were to become rules of the road, such as driving on the left and not damaging the road surface. Trusts could take additional tolls during the summer to pay for watering the road in order to lay the dust thrown up by fast-moving vehicles. Parliament also passed a few general Turnpike Acts dealing with the administration of the trusts and restrictions on the width of wheels – narrow wheels were said to cause

4819-592: 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

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4898-609: The roads of complete counties were put under single turnpike trusts in the 1760s. A further surge of trust formation occurred in the 1770s, with the turnpiking of subsidiary connecting roads, routes over new bridges, new routes in the growing industrial areas and roads in Scotland . About 150 trusts were established by 1750; by 1772 a further 400 were established and, in 1800, there were over 700 trusts. In 1825 about 1,000 trusts controlled 18,000 miles (29,000 km) of road in England and Wales. The acts of Parliament for these new trusts and

4977-401: 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,

5056-525: The technologies used to deal with geological features, drainage, and the effects of weather, were all in their infancy. Road construction improved slowly, initially through the efforts of individual surveyors such as John Metcalf in Yorkshire in the 1760s. 19th-century engineers made great advances, notably Thomas Telford and John Loudon McAdam . The engineering work of Telford on the Holyhead Road (now

5135-508: 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

5214-489: 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

5293-554: 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

5372-664: The use of parish statute labour. A parliamentary bill was tabled in 1621/22 to relieve the parishes responsible for part of the Great North Road by imposing a scale of tolls on various sorts of traffic. The toll revenue was to be used in repairing the road, however, the bill was defeated. During the following forty years, the idea of making travellers contribute to the repair of roads was raised on several occasions. Many parishes continued to struggle to find funds to repair major roads and in Hertfordshire , way wardens on behalf of

5451-549: The vestries stood frequent trial at quarter sessions for their failure to keep the Old North Road in a good state of repair. In 1656 the parish of Radwell, Hertfordshire petitioned their local sessions for help to maintain their section of the Great North Road. Probably as a result judges on the Hertfordshire, Cambridgeshire and Huntingdonshire circuit represented the matter to Parliament, it then passed an act that gave

5530-423: 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

5609-441: The work based on a specification dated September 1818. Brown knew little of masonry, and Rennie did this aspect of the work. The bridge proposal received consent in July 1819, with the authority of an Act of Parliament that had been passed in 1802, and construction began on 2 August 1819. The bridge, which has its western end in Scotland and its eastern end in England, was built with a single span of 449 feet (137 m). There

5688-573: The year before the Liverpool and Manchester Railway opened, the Warrington and Lower Irlam Trust had receipts of £1,680 but, by 1834, this had fallen to £332. The Bolton and Blackburn Trust had an income of £3,998 in 1846, but in 1847 following the completion of a railway between the two towns, this had fallen to £3,077 and, in 1849, £1,185. The debts of many trusts became significant; forced mergers of solvent and debt-laden trusts became frequent, and by

5767-454: Was adequate for roads that the parishioners used themselves but proved unsatisfactory for the principal highways that were used by long-distance travellers and waggoners. During the 17th century, the piecemeal approach to road maintenance caused acute problems on the main routes into London. As trade increased, the growing numbers of heavy carts and carriages led to serious deterioration in the state of these roads and this could not be remedied by

5846-643: 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

5925-577: Was fitted with iron rigging in 1806, and in a test voyage proved successful enough that in 1808, with his cousin Samuel Lenox, he set up a company that would become Brown Lenox & Co . Brown left the Navy in 1812, and in 1813 he built a prototype suspension bridge of 105 feet (32 m) span, using 296 stone (1,880 kg) of iron. It was sufficiently strong to support a carriage, and John Rennie and Thomas Telford reported favourably upon it. Brown took out

6004-552: Was impassable during periods of high water. The Berwick and North Durham Turnpike Trust took on responsibility for improving matters by issuing a specification for a bridge. The bridge was designed by an Royal Navy officer, Captain Samuel Brown . Brown joined the Navy in 1795, and seeing the need for an improvement on the hemp ropes used, which frequently failed with resulting loss to shipping, he employed blacksmiths to create experimental wrought iron chains. HMS  Penelope

6083-499: Was particularly intense in mountainous regions where good routes were scarce. In Mid Wales in 1839, new tolls on old roads sparked protests known as the Rebecca Riots . There were sporadic outbursts of vandalism and violent confrontation by gangs of 50 to 100 or more local men, and gatekeepers were told that if they resisted they would be killed. In 1844, the ringleaders were caught and transported to Australia as convicts. However,

6162-416: Was required to create each trust. The Act gave the trustees responsibility for maintaining a specified part of the existing highway. It provided them with powers to achieve this; the right to collect tolls from those using the road was particularly important. Local gentlemen, clergy and merchants were nominated as trustees and they appointed a clerk, a treasurer and a surveyor to actually administer and maintain

6241-404: 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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