The Clifton Suspension Bridge is a suspension bridge spanning the Avon Gorge, and linking Clifton in Bristol to Leigh Woods in North Somerset, England. Designed by Isambard Kingdom Brunel, it is a landmark that is used as a symbol of Bristol. It is a grade I listed building.[2]
The idea of building a bridge across the Avon Gorge originated in 1753 originally for a stone bridge with later plans for a cast iron structure. An attempt to build Brunel's design in 1831 was stopped by the Bristol Riots, and the revised version of his designs was built after his death, being completed in 1864. Although similar in size, the bridge towers are not identical in design, the Clifton tower having side cut-outs, the Leigh tower more pointed arches atop a 110 feet (34 m) red sandstone clad abutment. Roller mounted "saddles" at the top of each tower allow movement of the three independent wrought iron chains on each side when loads pass over the bridge. The bridge deck is suspended by eighty-one matching vertical wrought-iron rods.
Two men were killed during the construction of the bridge and since then it has become known as a suicide bridge and is fitted with plaques that advertise the telephone number of The Samaritans. The bridge is a distinctive landmark, used as a symbol of Bristol on postcards, promotional materials, and informational web sites. It has also been used as a backdrop to several films and television programmes.
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History
The idea of building a bridge across the Avon Gorge originated in 1753, with a bequest in the will of Bristolian merchant William Vick, who left £1,000 invested with instructions that when the interest had accumulated to £10,000, it should be used for the purpose of building a stone bridge between Clifton Down (which was in Gloucestershire, outside the City of Bristol, until the 1830s) and Leigh Woods in Somerset.[3]
By 1829, Vick's bequest had reached £8,000, but it was estimated that a stone bridge would cost over ten times that amount. An Act of Parliament was passed to allow a wrought iron suspension bridge to be built instead, and tolls levied to recoup the cost. A competition was held to find a design for the bridge; the judge, Thomas Telford, rejected all designs, and tried to insist on a design of his own, a suspension bridge supported on tall Gothic towers.[3] Telford claimed that no suspension bridge could exceed the 577 feet (176 m) span of his own Menai Suspension Bridge. A second competition, held with new judges, was won by Brunel's design on 16 March 1831, for a suspension bridge with fashionably Egyptian-influenced towers.[3]
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| A drawing of the Clifton Suspension Bridge from 1878 |
An attempt to build Brunel's design in 1831 was stopped by the Bristol Riots, which severely dented commercial confidence in Bristol.[4] Work was not started again until 1836, and thereafter the capital from Vick's bequest and subsequent investment proved woefully inadequate. By 1843, the towers had been built in unfinished stone, but funds were exhausted. In 1851, the ironwork was sold and used to build the Brunel-designed Royal Albert Bridge on the railway between Plymouth and Saltash.[5]
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| Shown within Bristol and the UK |
Brunel died in 1859, without seeing the completion of the bridge. Brunel's colleagues in the Institution of Civil Engineers felt that completion of the Bridge would be a fitting memorial, and started to raise new funds. In 1860, Brunel's Hungerford suspension bridge, over the Thamesin London, was demolished to make way for a new railway bridge to Charing Cross railway station, and its chains were purchased for use at Clifton. A slightly revised design was made by William Henry Barlow and Sir John Hawkshaw; it has a wider, higher and sturdier deck than Brunel intended, triple chains instead of double, and the towers were left as rough stone rather than being finished in Egyptian style. Work on the bridge was restarted in 1862, and was complete by 1864.[6]
The bridge is now managed by a trust set up by Act of Parliament in 1952. A toll of £0.50 is levied on vehicles, but the £0.05 toll that the Act allows for cyclists or pedestrians is not collected.[7]
The first modern bungee jumps were made on 1 April 1979 from the bridge, by members of the Oxford University Dangerous Sports Club.[8]
In 2003, the weight of crowds travelling to and from the Ashton Court festival and Bristol International Balloon Fiesta put such great strain on the bridge that it was decided to close the bridge to all traffic, including pedestrians, during the whole of the Ashton Court Festival and part of the Balloon Fiesta in 2004. The closure of the bridge for major annual events has continued each year since then.[9]
On 26 November 2003, the last ever Concorde flight (Concorde 216) flew over the bridge before landing at Filton Aerodrome.[10] It was a symbolic moment which commemorated Bristol's feats in engineering.
In April 2006, the bridge was the centrepiece of the Brunel 200 weekend, celebrating the 200th anniversary of the birth of Isambard Kingdom Brunel. At the climax of the celebration a firework display was launched from the bridge.[11] The celebrations also saw the switch on of anLED-based lighting array to illuminate the bridge.[12]
On 4 April 2009, the bridge was shut overnight due to a crack in one of the support hangers.[13]
Engineering
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| One of the chains, taken from the originalHungerford Bridge on the Thames. |
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| Profile of the Leigh Woods tower Although similar in size, the bridge towers are not identical in design, the Clifton tower having side cut-outs, the Leigh tower more pointed arches. Brunel's original plan proposed they be topped with then-fashionable sphinxes, but the ornaments were never constructed.[14] The 85 ft (26 m) tall Leigh Woods tower stands atop a 110 feet (34 m) red sandstone clad abutment. In 2002 it was discovered that this was not a solid structure but contained 12 vaulted chambers up to 35 feet (11 m) high, linked by shafts and tunnels.[15] Roller mounted "saddles" at the top of each tower allow movement of the chains when loads pass over the bridge. Though their total travel is minuscule, their ability to absorb forces created by chain deflection prevents damage to both tower and chain.[14][15] The bridge has three independent wrought iron chains per side, from which the bridge deck is suspended by eighty-one matching vertical wrought-iron rods ranging from 65 feet (20 m) at the ends to 3 feet (0.91 m) in the centre.[16] Composed of numerous parallel rows of eyebars connected by bolts, the chains are anchored in tunnels in the rocks 60 feet (18 m) below ground level at the sides of the gorge.[15] The deck was originally laid with wooden planking, later covered with asphalt, which has been renewed in 2009.[15] The weight of the bridge, including chains, rods, girders and deck is approximately 1,500 tons.[17] [edit]Dimensions
Suicides and accidentsTwo men were killed during the construction of the bridge.[17] In 1885, a 22-year-old woman named Sarah Ann Henley survived a fall from the bridge when her billowing skirts acted as a parachute; she subsequently lived into her eighties.[17] The Clifton Suspension Bridge is well known as a suicide bridge and is fitted with plaques that advertise the telephone number of The Samaritans. Between 1974 and 1993, 127 people fell to their deaths from the bridge.[21] In 1998 barriers were installed on the bridge to prevent people jumping. In the four years after installation this reduced the suicide rate from eight deaths per year to four.[22] Nicolette Powell, the wife of singer Georgie Fame, formerly the Marchioness of Londonderry, committed suicide from the bridge on 13 August 1993.[23] Although flying under the bridge has been outlawed since 1911, in 1957 a Filton-based RAF Vampire jet from 501 Squadron flew at high speed under the deck before crashing in Leigh Woods, killing the pilot.[24] A police helicopter flew under the bridge during a search in 1997.
Popular cultureThe bridge is a distinctive landmark, used as a symbol of Bristol on postcards, promotional materials, and informational web sites such as Visit Bristol.[25] BBC West uses a clip of the bridge in their opening titles for their regional news programme BBC Points West which serves the West TV region.[26] The bridge is also used as a backdrop on The West Country Tonight - a regional news programme broadcast by ITV West from their Bristol studios.[27] Construction of the bridge was featured in the Channel 4 television series The Worst Jobs in History,[28] as part of an episode entitled The Worst Industrial Jobs in History, first broadcast on 7 May 2006.[29] In 2011, the bridge featured in the BBC2 programme "Climbing Great Buildings" - when Dr Jonathan Foyle and Lucy Creamer climbed the bridge and went into the bridge supports.[30]
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