Welland Viaduct

Construction

During the late 1870s, the Midland Railway embarked upon the construction a new 17-mile line, to run between Kettering, Northamptonshire and Manton, Rutland.^[6] A key feature of the route selected for the railway was the valley of the River Welland, which would need to be traversed; it was quickly determined that a lengthy viaduct would be the best approach to doing so. During 1874, an Act of Parliament was passed, authorising the line's construction, including the envisioned viaduct.^[1] A contract for the construction of the viaduct was tendered, to which London-based civil engineering firm Lucas and Aird was awarded prime contractor status.^[6]

The viaduct was a significant and challenging undertaking for the era; to traverse both the Welland Valley and its flood plain, it had a length of 1,280 yards (1,171 metres), at the time, this was surpassed in length only by the elevated multi-track approach to London Bridge railway station.^[6][1] Its design was performed by consulting engineer William Henry Barlow and members of his company, including his second son Crawford, who served as the resident engineer during the work, and his former pupil Charles Bernard Baker. Crawford later described the Welland Viaduct as being: “one of the grandest and most perfect pieces of workmanship to be seen in the United Kingdom”.^[6]

In 1875, it was decided to establish a base camp for the construction team at the northern end of the proposed viaduct, adjacent to the village of Seaton and close to the border between Rutland and Northamptonshire.^[6] During a short space of time, 47 wooden huts for housing the site's workforce were raised. According to reports, each of these huts would have typically housed seven men, two women and three children, and collectively contained around 560 people, most of which would have been working on the viaduct's construction in one manner or another.^[6] A further 12 huts were also established at Gretton Hill.^[1]

The construction process for the viaduct was primarily achieved via monotonous and wearisome physical labour.^[6] It has been estimated that of every man which had been tasked with preparing the ground and building the earth works, each would have shovelled in excess of 20 tons of earth on average during each 12-hour shift of work. At its peak, a workforce of 3,500 people, assisted by 120 horses, had been employed along a 15 mile-long length of the route.^[6] Several works are known to have died during the viaduct's construction. A first-hand account of the workers and their living situation, entitled Life and Work Among the Navvies, was written by Reverend D W Barrett, the vicar of the nearby village Nassington.^[1]

The structure itself contains around 30,000,000 bricks, the majority of which having been fired onsite.^[6] W.H. Lorden served as the subcontractor for the brickwork, while the bricks themselves were produced by R. Holmes. Additional materials used included 20,000 cubic yards (15,000 m³) of concrete and 19,000 cubic yards (15,000 m³) of stone.^[1] Barrow lime was used to produce both the concrete and mortar used throughout, which was supplied by Ellis and Sons of Mountsorrel Junction, Leicester. The viaduct itself was built on land belonging to Lieutenant Colonel Tryon of Bulwick Hall.^[1]

During March 1876, the first brick of the viaduct was laid. During June 1877, it was announced that the first arch had been completed.^[7][1] By this point, the rate of process was rapid, all of the 82 arches of the structrure were constructed within the space of 13 months.^[6] On 5 July 1878, Lieutenant Colonel Tryon keyed the final arch of the structure in a ceremony to mark the viaduct's completion.^[7]

Operations

Once opened as a through passenger route on 1 March 1880, the Manton to Kettering line functioned to provide the city of Nottingham with a more direct link with London. Initially, a total of eight trains per day serving the line were scheduled, four in each direction.^[1] On 1 October 1885, a new train, named the Slip Coach, was added for the purpose of connecting with the fast trains to London, Northampton, Cambridge and the Eastern Counties at Kettering. By 1903, the route was carrying over a dozen express and stopping trains on both way on each day.^[1]

The viaduct has been threatened multiple times during its operating life. During 1906, the railway embankment just to the north of the viaduct collapsed as a result of heavy rain and insufficient drainage, leaving rails suspended in mid air and closing the line.^[8] During the First World War, the Welland Viaduct came under attack from a German Zepplin during 1916; it is believed that the Germans had recognised the route as having possessed strategic importance due to its role in transporting British troops to the ports on the English Channel and thus led to the decision to launching bombing raids against the line.^[9] During 1939, the viaduct was subject to threats of bombing by the Irish republican paramilitary organisation, the IRA; as a consequence, the area around structure was placed under guard by the police for the purpose of deterring such an attack.^[10]

During 1967, as a consequence of the nation-wide Beeching cuts, all regular passenger services formerly using the viaduct were discontinued; however, the line remained open for use by freight traffic.^[1]

As a result of several factors, including the structure's size, age, exposure and inaccessibility, the original brickwork has suffered from extensive weathering and structural deterioration over the years. Before the extensive privatisation of British Rail, repairs were regularly made to the structure by the Kettering and Leicester civil engineering staff. Many of the older bricklayers reported having seen the imprints of children's hands and feet in the bricks, from where they had walked on the clay-filled moulds before firing in the kiln. The viaduct was originally built from bricks which had been manufactured and fired onsite, which have a red face. Subsequent repairs have often employed other types of bricks, predominantly blue engineering bricks, which provide for superior water resistance and are much stronger than typical bricks, which makes them particularly well-suited for arch re-lining and face brick replacement. The use of different bricks has gradually given the viaduct a red-and-blue patchwork appearance.^[6]

During 2004, as part of the national infrastructure owner Network Rail's continuous structures maintenance programme, civil engineering company Birse Rail was remitted to perform several structural repairs to the viaduct; this restorative work was carried out at a cost of £1.5m (equivalent to £2,110,000 in 2016).^[11]. Reportedly, traditional methods and materials were employed alongside modern access techniques to return the structure to its former glory and to ensure the long-term structural integrity of the viaduct, as well as the enjoyment of generations to come.^[12]

Between 2016 and 2017, Welland Viaduct was subject to a comprehensive programme of works under Network Rail’s Infrastructure Projects East Midlands Civils Renewals and performed by engineering firm Amco Rail.^[6] This renewal intended not only to address all of the recorded defects in the brickwork defects, but to also prepare the structure for a long-term strengthening scheme aimed at raising its restrictive load capacity rating from RA0 (the lowest rating) to RA10 (the highest rating) so that traffic can traverse it quicker. Specifically, 25-tonne axle-load freight has been limited to 20mph when passing across the viaduct; an envisioned goal of the strengthening measures is to increase this to 60mph.^[6][13]

Structural improvements made to the Welland Viaduct involved a variety of measures and design alterations being implemented.^[6][13] The parapets had 20mm joints saw-cut through them to allow for some sheer movement, thus reducing the rate of cracking, while over 2,300 20mm-diameter vertical reinforcement bars were installed at one-metre intervals through the brickwork to better achor the parapets and structure together. Furthermore, vertical cracks were addressed via the fitting of 6mm stitch bars where applicable, and galvanised steel angle brackets fixed onto either side of joints where the outwards lean exceeded 40 mm.^[6] Unlike prior repairs, Network Rail required that no further use of pattress plates be made on the viaduct. Core-drilling of the parapets was performed by a bespoke 900kg rig, developed by Amco Rail, which was credited with having reduced the programme's cost by £200,000 over conventional means even when including its development cost.^[6][13]

Citations

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Bibliography