Rail line landmark restoration via pultrusion
Great Britain’s extensive railway network includes historic and, often, picturesque infrastructure. One example is the Carlisle Bridge in Lancaster. Set in the Lancashire region of northwestern England, the 110m bridge over the River Lune began carrying rail traffic in 1847. A key element of the West Coast main line, it is part of the London-to-Glasgow rail route.
The rail bridge includes an access stairway and pedestrian footbridge along one side, which protects walkers with fencing and handrails. Previous metal fencing elements had been replaced numerous times, but given the wet climate, were badly rusted again. Network Rail (London, UK), the entity responsible for maintaining the railway, wanted a fencing/handrail product that would combine a suitable aesthetic with high strength, light weight — to avoid adding more weight to the bridge — and, most importantly, corrosion resistance, to eliminate the previous rounds of costly maintenance — repairs, painting and, ultimately, complete overhauls.
Network Rail selected Pipex px (Roborough, Plymouth, UK), a British manufacturing, engineering and design firm, to develop a composite solution to replace the corroded metal footbridge and stairway railings. Pipex px, a distributor for pultruder Strongwell (Bristol, VA, US), specified Strongwell’s trademarked EXTREN Series 525 pultruded glass/polyester structural shapes in slate gray color, including I-beams, square tubes and round tubes, as well as flat plates for attaching the railing system to the bridge parapets. Series 525 incorporates fire-retardant additives and an ultraviolet (UV) inhibitor. The fencing and handrail system ranges from 1.07m to 2.44m high, and was assembled offsite, then installed along both sides of the rail bridge and the stairways by Story Contracting (Carlisle, UK).
In total, 564 linear meters of assembled FRP fencing was installed. Reportedly, both the installers and end-users are delighted with the outcome of the completed refurbishment project. The composite fencing and handrail at Carlisle Bridge is anticipated to last more than 60 years in continuous service.
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