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Greyhound Bridge
River Lune, Lancaster, Lancashire, UK
Greyhound Bridge
associated engineer
John Watson
C.S. Allot & Son
J.H. Strang
date  1849 (dem), 1862 - 1864 (dem), 1910 - 28th October 1911, 1971 - 1972
era  Modern  |  category  Bridge  |  reference  SD476621
photo  David Hurford
Greyhound Bridge in Lancaster looks like a 20th century road bridge, but its history is more complex. It was preceded by a Victorian timber rail viaduct, demolished in favour of an iron version, in turn demolished after the completion of a steel version in 1911. The steel viaduct was converted for road use by the addition of a concrete deck, which is what we can see today. Greyhound Bridge carries the A6 trunk road over the River Lune, and is undergoing refurbishment (2018).
The first bridge at this spot was an 1849 viaduct carrying the 'Little' North Western Railway (so called to avoid confusion with the much larger London & North Western Railway) that ran from from east of Lancaster to Poulton-le-Sands. The railway provided a direct link from towns in Lancashire and Yorkshire to the coast, leading to the popularity of Poulton-le-Sands as a resort — it would be renamed Morecombe in 1889.
The twin-track 189m viaduct was constructed in timber and engineered by John Watson (c.1816-90). Richard Smallman (1816-1872), the railway company’s resident engineer during 1847-57, presumably supervised. As with the present bridge, the viaduct was curved in plan, crossing the River Lune diagonally — a plan curve of 179.8m radius at 40 degrees of skew, with 10 spans of 18.3m.
The piers consisted of timber piles with cast iron shoes, with the piles arranged in three cross-braced clusters. They supporting three arched ribs of laminated three inch timber planks. The deck was suspended from the arches on iron suspension rods. The rails sat a little above the springing, with one track running either side of the central arch. Watson and the Government Inspector of Railways, Captain George Wynne (1804-90), load tested the viaduct with a pressure of 99.6 tonnes "concentrated upon one arch" and recorded a deflection of only 16mm.
The Midland Railway operated the line from June 1852, leasing it in 1859. In 1862-4, the viaduct was replaced in wrought iron, preserving its curved alignment. Cylindrical cast iron caisson were used for the new piers, set three on each outer edge with a pair in the centre, cross-braced with slender rods. The deck was carried between heavy beams of riveted wrought iron lattices. On 1st January 1871, the line was taken over completely by the Midland Railway.
Then in 1910-11, a completely new two-track steel viaduct was constructed alongside the wrought iron one. Named the Greyhound Bridge, it opened on 28th October 1911. The old structure was demolished, and its wrought iron girders used for the construction of Halton Station Bridge (north east of Lancaster, completed 1913), which is still in use today.
The new viaduct was 204.3m long and 12.7m wide, with nine spans. Its eight river piers consisted of pairs of cross-braced tubular caissons. The deck was constructed using two 2m deep riveted plate girders joined at the base by a series of riveted cross girders. Tarred concrete access walkways and handrails were mounted on top of the plate girders.
Passenger services ceased on the line on 1st January 1966 (freight journeys continued until 3rd June 1967) — the Morecombe to Wennington line was among those slated for withdrawal by Dr Richard Beeching (1913-85) in his1963 government report The Reshaping of British Railways.
Unusually, it was decided to convert Greyhound Bridge for vehicular use. The works, undertaken in 1971-2, were designed by C.S. Allot & Son of Sale in Cheshire (later Allot & Lomax, now part of Jacobs). The scheme's engineer was J.H. Strang, Lancaster City Engineer & Surveyor, working in consultation with James Drake (1907-89, CBE 1962, knighted 1973), Lancashire County Surveyor & Bridgemaster 1945 to 1972.
The viaduct's access walkway and handrails were removed, leaving the piers and steel superstructure on which was constructed a much wider reinforced concrete deck. A series of steel stools and diagonal struts mounted on the original pier cross frames help support the new deck.
On the downstream (west) side, the deck cantilevers 2.4m, and on the upstream side 915mm. It carries a 9.1m wide three-lane highway, with a single 1.8m wide footpath on the west side. The parapets are 533mm high steel post and rail fencing. The transverse gradient of the carriageway slopes 1 in 24 towards the upstream side.
On 29th January 2018, the bridge closed to traffic for major maintenance by Lancashire County Council. The £4m project will repair chloride damage to the concrete deck and ensure the structure’s capacity to take heavy goods vehicles.
Most of the work concerns the concrete deck, though the underlying steelwork is being repainted to prevent corrosion. The project includes the cleaning, repainting and greasing of the bridge bearings, breaking out areas of damaged concrete and recasting (20 transverse beams, 16 discontinuity joints, four expansion joints), installing galvanic cathodic protection, drainage repairs, deck waterproofing and resurfacing, parapet repainting and new signage. Overall there will be some 12,500 sq m of resurfacing, 7,500 sq m of painting and 3,000 sq m of waterproofing.
Two of the three lanes are expected to re-open on 4th August, with completion in late autumn 2018.
Contractor (2018): A.E. Yates Ltd, Bolton
Research: ECPK
bibliography
"Opening of a portion of the Lancaster branch of the North-Western Railway", The Illustrated London News, 3rd November 1849
https://regionalheritage.omeka.net
www.aeyates.co.uk
www.lancashire.gov.uk
www.lancaster.gov.uk
Thanks to David Hurford for additional information
Location

Greyhound Bridge