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The magnificent Victorian station at Tynemouth stands on the coast east of Newcastle, built in 1882 by the North East Railway. It was designed by William Bell, the chief architect of numerous stations and highly regarded for the quality of his roof and canopy designs. These canopies are currently subject to a major restoration project, with Gifford (now part of Ramboll) acting as conservation engineer.
The station was built to transport the expanding local population, local goods services and crowds of seaside trippers. But changing patterns of tourism and industry meant that by the 1960s the station had declined into a considerable state of disrepair. In the 1980s the central bays of the station became part of the electrified Metro Tyne and Wear network that still operates today.
The station is in a conservation area and received grade II listing in 1978, upgraded to II* in 2003. During the 1980s several phases of refurbishment were carried out, including works to the canopies on the west platform, the footbridge, the five central canopies on the east platform and the adjoining station buildings. However, the remaining canopies fell into a very poor state, and due to the historical importance of the station, it received front page billing on the English Heritage “Buildings at Risk” review in 2008.
Gifford was appointed as conservation structural engineer in 2009 to investigate and report on the condition of the glazed canopies by Station Developments Ltd, a joint venture between the station owner and north Tyneside council. The architect for the work is Lathams.
The canopies follow the gentle curve of the platforms, creating an impressive fan arrangement of supporting ironwork. They are split into glazed bays, 19 bays over the west platform and 23 over the east. The glazed roof is pitched between each bay, separated by a valley gutter. At the gutter position there is a lattice truss, spanning perpendicular to the platform with a cantilever section against the platform edge and vaulted arch trusses between. The lattice trusses sit into the side of cast iron columns with filigree brackets at the junction between column and truss.
In March 2009 I carried out a detailed “finger touch” survey along with fellow Gifford engineer Joe Hinchcliffe using access platforms. We found the condition of the canopies varied, with the worst affected ironwork in the end bays where there had been greater exposure to the elements. The cantilever canopies were generally in a poor condition, with most requiring additional temporary support. The main problems encountered with the iron work included delamination of the top and bottom truss members, loss of rivets and bolts and fractures in the columns at the level of the bottom of the truss due to the expansion of corrosion deposits and thermal movement.
As well as the survey work, we agreed to carry out trial repair work on an end truss to the south. Part of the truss was removed and sent to an iron work restoration specialist. The trial repairs allowed the team to discuss appropriate methods for further repairs with English Heritage. We analysed the extent of dismantling required and a cost consultant used the results of the trials and the survey to produce accurate project costs.
Our detailed drawings showed the extent of replacement required and were reviewed by Gifford project director James Miller, a conservation accredited engineer. We issued repair details to English Heritage and North Tyneside Council as part of the submission for listed building consent.
We proposed that the trusses requiring the most significant repair should be dismantled and taken off-site. Tynemouth is an operational station and some repairs are simply not feasible on-site. The columns can be safely left but the extensive corrosion of rivets means that many require replacement with dome headed bolts. Truss members lost by corrosion are being reconstructed with mild steel angles and plates. Existing bolts will be replaced in stainless steel with bimetallic insulation.
The proposed repairs were approved by English Heritage and North Tyneside in February 2010, the project received funding early in 2011 and works started on site in April. To date, several of the cantilever trusses have been removed and are currently being assessed in the workshop. The project is proceeding on schedule and due to be completed in April 2012.
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