An existing masonry arch railway bridge in Huyton needed strengthening as part of an upgrade to the railway network.
The main contractor strengthened the existing arch by forming a sprayed concrete lining 450mm thick underneath the intrados of the existing brick arch. Prior to spraying the concrete lining, steel mesh reinforcement was fixed into the existing arch. For aesthetic reasons, the client required this sprayed concrete lining at each end of the bridge to be faced with brickwork. To enable this, the concrete lining was stopped short at each end by approx 500mm.
Once the main contractor had finished the sprayed concrete lining works we were called in to construct the brick facing. This consisted of a two brick wide by one brick thick facing to the piers either side of the arch and a one brick thick by 4 ring deep arch. The brickwork was constructed in ‘Furness Bricks’ 73mm high old terracotta blend built in a sand/lime/cement mortar. The mortar joints were pointed flush and then ‘rubbed’ to give an aged appearance. The brickwork was tied to the new concrete lining as the work proceeded by building in stainless steel ties slotted into stainless steel dovetail channels which were cast into the concrete by the main contractor.
To construct the arch we installed a temporary timber turning piece which was fixed to the new concrete lining. On completion of the arch, the brickwork was allowed to set prior to the removal of the temporary turning piece. The mortar joints to the intrados of the arch were then pointed to match.
Temporay timber turning piece installed and brickwork underway.
Turning of arch underway.
Close up of arch brickwork.
Completed arch, temporary timber turning piece still in place until the brickwork sets.
Close up of completed arch, temporary timber turning piece still in place until the brickwork sets.