Royal Albert Bridge

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Royal Albert Bridge
Carries Railway
Crosses River Tamar
Locale Between Plymouth and Saltash,
United Kingdom
Maintained by Network Rail
Designer I K Brunel
Design Lenticular truss
Material Iron
Total length 2,187.5 feet (666.8 m)
Width 16.83 feet (5.13 m) (inside piers)
Height 172 feet (52.4 m)
Longest span 2 of 455 feet (138.7 m)
Number of spans 19
Piers in water 3
Clearance below 100 feet (30 m)
Construction begin May 1854
Construction end April 1859
Opened 2 May 1859
Coordinates 50°24′27″N 4°12′12″W / 50.407575°N 4.203389°W / 50.407575; -4.203389Coordinates: 50°24′27″N 4°12′12″W / 50.407575°N 4.203389°W / 50.407575; -4.203389

The Royal Albert Bridge is a railway bridge that spans the River Tamar in England, United Kingdom between Plymouth, on the Devon bank, and Saltash on the Cornish bank. Its unique design consists of two 455 feet (138.7 m) lenticular iron trusses 100 feet (30.5 m) above the water, with conventional plate-girder approach spans. This gives it a total length of 2,187.5 feet (666.8 m). It carries the Cornish Main Line railway in and out of Cornwall.

It was designed by Isambard Kingdom Brunel. Surveying started in 1848 and construction commenced in 1854. The first main span was positioned in 1857 and the completed bridge was opened by Prince Albert on 2 May 1859. Brunel died later that year and his name was then placed above the portals at either end of the bridge as a memorial. Work was carried out during the twentieth century to replace the approach spans and strengthen the main spans. It has attracted sightseers since its construction and has appeared in many paintings, photographs, guidebooks, postage stamps and on UK£2 coin. Anniversary celebrations took place in 1959 and 2009.

Cornwall Railway

Two rival schemes for a railway to Falmouth, Cornwall were proposed in the 1830s. The 'central' scheme was a route from Exeter around the north of Dartmoor, an easy route to construct but with little intermediate traffic. The other, the 'coastal' scheme, was a line with many engineering difficulties but which could serve the important naval town of Plymouth and the industrial area around St Austell. The central scheme was backed by the London and South Western Railway while the coastal scheme was supported by the Cornwall Railway and backed by the Great Western Railway which wanted it to join up with the South Devon Railway at Devonport. The Cornwall Railway applied for an Act of Parliament in 1845 but it was rejected, in part because of William Moorsom's plan to carry trains across the water of the Hamoaze on the Torpoint Ferry. Following this Isambard Kingdom Brunel took over as engineer and proposed to cross the water higher upstream at Saltash. The Act enabling this scheme was passed on 3 August 1846.[1]

Design

A drawing of one span and its piers

The structure was the third in a series of three large wrought iron bridges built in the middle of the nineteenth century and was influenced by the preceding two, both of which had been designed by Robert Stephenson. The two central sections of Brunel's bridge are novel adaptations of the design Stephenson employed for the High Level Bridge across the River Tyne in Newcastle Upon Tyne in 1849. Brunel was present when Stephenson raised the girders of his Britannia Bridge across the Menai Strait in the same year.[2] From 1849 to 1853 Brunel was erecting an iron bridge of his own; the Chepstow Bridge carried the South Wales Railway across the River Wye and featured a main truss of 300 feet (91 m) with a curving tubular main member and three conventional plate-girder approach spans of 100 feet (30 m), a similar solution to that adopted for crossing the River Tamar at Saltash.[3]

The river is about 1,100 feet (340 m) wide at Saltash. Brunel's first thoughts had been to cross this on a timber viaduct with a central span of 255 feet (78 m) and six approach spans of 105 feet (32 m) with 80 feet (24 m) clearance above the water. This was rejected by the Admiralty, who had statutory responsibility for navigable waters, and Brunel thus produced a design to give 100 feet (30 m) clearance, with two spans of 300 feet (91 m) and two of 200 feet (61 m).[4] The final design as built consists of two main iron spans of 455 feet (138.7 m) with 100 feet (30.5 m) clearance above mean high spring tide. These two spans are lenticular trusses with the top chord of each truss comprising a heavy tubular arch in compression, while the bottom chord comprises a pair of chains. Each of the trusses is simply supported and therefore no horizontal thrust is exerted on the piers, which is crucial in view of the curved track on either side. Between these two chords are supporting cross-bracing members and suspension standards which hang beneath the bottom chord to carry the railway deck which is a continuous plate beam. There are also seventeen much shorter and more conventional plate-girder approach spans on the shore. On the Cornish side there are ten which measure (from Saltash station towards the river): 67.5 feet (20.6 m), 69.5 feet (21.2 m), 69.5 feet (21.2 m), 69.5 feet (21.2 m), 69.5 feet (21.2 m), 69.5 feet (21.2 m), 72.5 feet (22.1 m), 78.0 feet (23.8 m), 83.5 feet (25.5 m), 93.0 feet (28.3 m), and seven on the Devon side of (from the river towards St Budeaux): 93.0 feet (28.3 m), 83.5 feet (25.5 m), 78.0 feet (23.8 m), 72.5 feet (22.1 m), 69.5 feet (21.2 m), 69.5 feet (21.2 m), 69.5 feet (21.2 m). This gives a total length for the nineteen spans of 2,187.5 feet (666.8 m).[3]

History

Construction

A tide recorder designed by Brunel as part of his survey

The first work was to properly survey the river bed. On 26 April 1848 a 6 feet (1.8 m) iron cylinder 85 feet (25.9 m) tall was launched into the Tamar. From the bottom of this the bed of the river could be examined to identify its nature and the location of solid foundations. The Cornwall Railway at this time was finding it difficult to raise funds and so most operations were suspended that summer, but a small fund was allowed for Brunel to continue the survey. The cylinder was positioned at 35 different places and a total of 175 borings made.[3]

In 1853 the tenders for the bridge were considered by the Cornwall Railway Board, and it was decided to let the work to Charles Mare, a shipbuilder from Blackwall who had built the ironwork for the Britannia Bridge. The fee he sought for building the Saltash Bridge was £162,000, but on 21 September 1855 he filed for bankruptcy. Brunel proposed that the company should take over the works on the bridge without engaging another contractor, to which the company agreed.

The first span and centre pier under construction in 1854, seen from Saltash

Mare's first task had been to establish an erecting yard on the Devon shore with a jetty and workshops. He then proceeded to construct a 37 feet (11.3 m) iron cylinder 90 feet (27.4 m) tall which was to form the work base for the construction of the central pier. This was launched in May 1854 and moored in the centre of the river between four pontoons. The bottom had been shaped to follow the rock surveyed in 1848; once it was settled on the river bed the water was pumped out, the mud within it excavated, and a solid masonry pier built up clear of the water. This was completed in November 1856.

The landward piers on the Cornish side of the river were completed in 1854 and the girders for these spans were hoisted up to their correct positions. Next to be built was the main truss for the Cornwall side of the river. The lower ties of the trusses formed of chains made from 20 feet (6.1 m) links. Many were obtained from the suspended works for Brunel's Clifton Suspension Bridge and others rolled new for Saltash. The Cornwall span was floated into position on 1 September 1857 and jacked up to full height in 3 feet (910 mm) stages as the piers were built up beneath it, the central pier using cast iron octagonal columns; the landward one using ordinary masonry.

The second span soon after it was floated onto the piers and had been jacked up the first 12 feet (3.7 m) towards its final position

With the yard now cleared of the first truss, work could start on the main Devon span. This was similarly floated into position on 10 July 1858 and then raised in a similar manner; it was in its final position by 28 December 1858. After this had been removed, part of the yard had to be cleared to allow the construction of the final landward pier and then the Devon approach spans could be raised up to their final position. The work was sufficiently advanced that directors were able to make an inspection by train on 11 April 1859.

The Cornwall span had been tested before it was launched. The two ends were supported on substantial timber piers and the remaining scaffolding removed. Static loads of 1.25 and then 2.25 tons per foot were placed on the deck, the deflections measured and any permanent change measured once the road was removed. Now that it was completed, the bridge had its statutory inspection and tests by Colonel Yolland on behalf of the Board of Trade on 20 April 1859. He ran a heavy train over the bridge and measured deflections in the main trusses of 1.14 inches (29 mm) in the Devon truss, and 1.20 inches (30 mm) in the Cornwall one. Overall he described it as 'highly satisfactory'.[3]

Opening day

Prince Albert had agreed to the bridge being named after him as early as 1853. He was also invited to perform the opening ceremony, and on 2 May 1859 he travelled from Windsor on a special train. Several thousand spectators attended that day, but illness prevented Brunel's attendance,[5] and guests from Cornwall were late for the ceremony as their train broke down at Liskeard.[6] Public services commenced on 4 May 1859.[4]

Changes since 1859

The words I.K. BRUNEL, ENGINEER, 1859 appear in large metal letters on either end of the bridge, added as a memorial after his death on 5 September 1859. In 1921, new access platforms were added that obscured the lettering but in 2006 Network Rail relocated the platforms, allowing the name to be clearly seen again.[7] The walkways had previously been temporarily removed in 1959 and the bridge floodlit during its centenary year.[3]

401 new cross-girders were fitted in 1905 to allow heavier locomotives to pass over. In 1908 the two spans nearest Saltash station were replaced with wider ones to accommodate a new track layout. The remaining approach spans were replaced on both sides of the river during 1928 and 1929. During the 1930s new cross-bracing and diagonal sway-bracing were added between the vertical standards to further strengthen the bridge and keep the suspension chains hanging in the correct shape.[3]

Viewing the bridge

Looking out from the view point by the Tamar Bridge office on the Devon bank

It is still possible to travel over the bridge by using a train on the Cornish Main Line, and pass below it on the River Tamar. Cruise boats operate between Phoenix Wharf, Plymouth, Saltash, and Calstock.[8] There are also several view points around the bridge.

The Cornish approach spans start right at the platform end. These were replaced in 1908 so that the single line on the bridge could split into two lines before reaching the station.
The foreshore at Saltash runs right up to the pier that supports the Cornish end of the main span. An inscribed stone commemorating the bridge can be found beneath the bridge on the hillside alongside Fore Street.
The road bridge lies parallel to and slightly higher than the railway bridge on its north side. A toll-free foot and cycle path is situated on the south side of the road bridge from which it is possible to examine the bridge in detail. An area of grass beside the motor vehicle toll booths affords a view of the Devon end of the railway bridge.
The Devon piers can be reached from the waterfront at St Budeaux. The yard where the spans were constructed was situated alongside the bridge at the foot of the road down the hill.
Panorama of the Royal Albert Bridge and the Tamar Bridge

Cultural impact

Bench seat at the Brunel Museum, Rotherhithe, London incorporating a model of the bridge

The construction of such a large and distinctive bridge soon caught the attention of the general public. The launching of the Cornish span in 1857 attracted a crowd of around 20,000,[5] and many people also came to witness the launch of the Devon span and the opening day.[3] During its construction it was photographed many times and after its opening it was the subject for many paintings, including those by local artist Alfred Wallis.[9] It has also been the subject of many photographs and postcards.[10]

It was already a feature in guidebooks in the year of its opening: It is a labour of Hercules, but Mr Brunel has accomplished the feat proclaimed one, and went on to report in detail the design and construction of the bridge that for novelty and ingenuity of construction stands unrivalled in the world.[11] More than 100 years later it continues to appear in many travel guides and features.[12] John Betjeman summed up its impact on the traveller:

The general grey slate and back gardens of Plymouth, as seen from the Great Western made the surprise of Saltash Bridge all the more exciting. Up and down stream, grey battleships were moored in the Tamar and its reaches. Hundreds of feet below, the pathetic steam ferry to Saltash from the Devon bank tried to compete with Brunel's mighty bridge.[13]

The bridge has become a symbol of the transition from Devon to Cornwall. In the Great Western Railway's The Cornish Riviera travel guide, SPB Mais regarded it as an almost magic means of transporting travellers from a county, which, if richer than others, is yet unmistakingly an English county, to a Duchy which is in every respect un-English. You shut your eyes going over the Saltash Bridge only to open them again on a foreign scene.[14] However, Cornish people look at it in the other way; in the song "Cousin Jack", English folk duo Show of Hands sing I dream of a bridge on the Tamar, It opens us up to the East.

The bridge is also the backdrop of ITV1's The West Country Tonight during the old westcountry region.

Special events

A new commemorative plaque was unveiled at Saltash station on 4 May 2009 to recognise the 150th anniversary of the bridge

Special occasions have been marked over the years by special events:

  • 1859 – The bridge was opened by Prince Albert two days before the railway was opened to the public. He arrived by special train from Windsor, was shown around the bridge and the works yard, and then left aboard the Royal Yacht.[3]
  • 1959 – Floodlights lit up the bridge during 1959 in celebration of its centenary.[3]
  • 2006 – The anniversary of Isambard Kingdom Brunel's 200th birthday was celebrated by Network Rail permanently removing the access ways that covered his name above the portals.[7]
  • 2009 – 2009 was the 150th anniversary of the opening of the bridge. During the bank holiday weekend of 2–4 May there were many special events to commemorate this, including a guided walk across the bridge and a re-enactment of the opening day.[15]

References

  1. ↑ Ostler, Edward (1982). History of the Cornwall Railway 1835–1846. Weston-super-Mare: Avon-Anglia. ISBN 0-905466-48-9. 
  2. ↑ Norrie, Charles Matthew (1956). Bridging the Years – a short history of British Civil Engineering. Edward Arnold (Publishers) Ltd. 
  3. ↑ 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 Binding, John (1997). Brunel's Royal Albert Bridge. Truro: Twelveheads Press. ISBN 0-906294-39-8. 
  4. ↑ 4.0 4.1 MacDermot, E T (1931). History of the Great Western Railway, volume II 1863–1921. London: Great Western Railway. 
  5. ↑ 5.0 5.1 Bennett, Alan (1990). The Great Western Railway in East Cornwall. Cheltenham: Runpast Publishing. ISBN 1-870754-11-5. 
  6. ↑ "Illustrated Railway Supplement". West Briton & Cornwall Advertiser (2547). 1859. 
  7. ↑ 7.0 7.1 "Brunel's Royal Albert Bridge unveiled in all its splendour". Network Rail. Retrieved 24 March 2010. 
  8. ↑ "Plymouth Boat Cruises". Sound Cruising. Retrieved 16 July 2008. 
  9. ↑ Blair, Andy. "Alfred Wallis: Artist & Mariner". Retrieved 15 July 2009. 
  10. ↑ "Photos of Saltash". Francis Frith. Frith Content Inc. Retrieved 21 August 2009. 
  11. ↑ Murray, John (1859). Murray's Handbook for Devon and Cornwall. London: John Murray. ISBN 0-7153-5293-8. 
  12. ↑ Hesp, Martin (7 July 2008). "My magnificent rail journey". Western Morning News. Western Morning News. Retrieved 14 July 2008. 
  13. ↑ Perry, George (editor) (1970). 'The Book of the Great Western. London: Sunday Times Magazine. ISBN 0-7230-0018-2. 
  14. ↑ Mais, SPB (1934). The Cornish Riviera (3rd ed.). London: Great Western Railway. 
  15. ↑ "Events list". Royal Albert Bridge official website. Retrieved 8 April 2009. 

Further reading

  • Mosley, Brian. "Royal Albert Bridge". Encyclopedia of Plymouth History. Plymouth Data. Retrieved 22 August 2008. 

External links

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