The Skelton Viaduct, also known as the Hook bridge or Goole railway swing bridge, is a large viaducted hogback plate girder bridge with swing span over the River Ouse, Yorkshire near Goole. The bridge was designed by Thomas Elliot Harrison for the Hull and Doncaster Branch of the North Eastern Railway and opened in 1869. In the latter part of the 20th century, the bridge became known for the frequent incidents involving ship collisions with the superstructure. As of 2020, it is still in use.
The bridge consisted of four fixed spans, one swing span and a fifth swing span, and carried a double-track railway. Pier foundations for the bridge spans were of base diameter cast iron cylinders, which tapered to diameter at the high water level, each column was around long. The piers were sunk into the river alluvium using a mass placed on them, and then by the pneumatic Caisson process until bedrock was reached. The tubes were then filled with Portland cement concrete to within of the top, the final fill was with brickwork with a top course of granite. The river abuttments were of brick with stone dressing. The fixed spans were long, made of three wrought iron hogback plate girders each, resting on three piers. The swing span was constructed of three hogback wrought iron box girders, each long, each box girder having a thickness of made of plates thick. In addition to the transverse deck girders the swing span was also braced by three transverse frames, which also served to support a bridgeman's hut over the centre of the bridge. The swing span was supported and turned on 26 conical rollers, which were supported by an annular box girder high by wide, itself resting on six of the cast iron piers with approximately of the pier sunk into the river bed. The bridge rotated around a central column, which contained a hydraulic accumulator of stroke, with diameter ram loaded to, used to power the turning mechanism. The bridge was turned by a three-cylinder hydraulic motor, and gears. The accumulator was charged by steam engines, also duplicated. The engines were supplied by field boilers also located on the central pier. When in the closed position a hydraulic mechanism at either end of the bridge was used to lock the bridge in position. The bridge could be opened in 50 seconds. The bridge superstructure was designed was T.E. Harrison of the NER, and erected by Pease, Hutchinson and Company. The fixed spans were supplied by Butler and Pitts, the hydraulic motors were of the design of Sir W.G. Armstrong. The swing span weighed, the weight of iron in the piers, with of iron in the girders. The swing span opening was over in width, with a height above high water when closed of over, The swing pier included a river jetty long. The bridge was crossed by NER officials in 1868, and the line opened on 2 August 1869.
Working history
On 21 March 1922, the river pier and engine room of the swing span was badly damaged by fire. In May 1933, the LNER had a miniature thumb switch controlled signalling frame installed at the bridge by Westinghouse, at the same time the line from Staddlethorpe to Goole had colour light signalling installed; both were early examples of either technology in use. At the same time, two signal boxes at either end of the bridge were closed. The bridge has had several collisions with water-going ships. On 21 December 1973, the bridge was struck by a German coaster, causing one of the spans to fall into the river, leaving the bridge unworkable for nine months. On 2 August 1976, Danish vessel Leon Sif hit one of the bridge's piers. British Rail began closure procedures for the railway line due to costs associated repairing the bridge's pier, estimated at £2 million, coupled with a historic failure to get adequate compensation for damage to the bridge caused by shipping. In 1987, the structure was given a grade II* listing by English Heritage. On 23 November 1988, one of the fixed spans was pushed out of alignment by a collision with the Swedish vessel Samo, which became trapped between the bridge's piers. By the early 21st century, understrength girders and corrosion had led to the line speed over the bridge being reduced to for passenger trains, down to only for trains with a route availability of 9 or more. In 2009, a modernisation programme began – Clancy Docwra installed services to the central pier through piping under the river bed. Carillion was appointed main contractor in March 2010. The bridge steelwork was repaired and upgraded over a six-week line closure starting in October 2010 – over 400 tonnes of steelwork was installed including diagonal transverse braces, and stiffening to the girders of the web. Additional work included track renewal and painting of the bridge. The total cost of the project was £6 million; the firm of Pell Frischmann was the designing engineer.
