21 September 2014

Yorkshire Bridges: 6. Ribblehead Viaduct

TripAdvisor reckons this imposing railway viaduct is in the top 30 out of over 400 visitor attractions in North Yorkshire. That's some distinction for an elderly railway bridge situated far from significant towns and cities amidst the windswept moors.

Ribblehead Viaduct is the largest and probably the most famous structure on the Settle to Carlisle Railway. As with the rest of the line, it was built to the design of John Sydney Crossley.

The bridge comprises 24 brick arches, with stone spandrel walls, supported on 6-foot thick stone-faced piers. Every sixth pier is 18-foot thick, and acts as a "bookend" which would in theory allow part of the viaduct to stand up even if the arches on the other side were to collapse. This is a common feature on large viaducts of this type.

The photographs show bands of black and red brickwork. I believe the red brick has been re-cased as part of extensive repair works undertaken in the early 1990s. Some of these repairs are illustrated on the Settle and Carlisle Railway Trust website.

Several pattress plates can be seen which anchor tie bars across the arch barrels. These have been installed at some point to restrain outward movement of the spandrel walls. Photos from the repair works show longitudinal cracks in the arch barrels along the lines of the spandrels, associated with this movement.

New drainage downpipes can be seen on the piers, and the top level of these corresponds to the backing material that sits above the piers and between each of the arch barrels. This backing is essential to the stability of the arches.

Projecting stones are visible at height on each of the piers which will have originally been used to support the temporary timber centering upon which each arch was erected.

The bridge's main attraction is its setting amidst pretty bleak moorland.

Further information:

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