Carrick-on-Shannon Pedestrian and Cycle Bridge, Co Leitrim

Doran Consulting was commissioned by the National Roads Authority to design a new 5-span pedestrian and cycle bridge over the River Shannon in Carrick-on-Shannon. The new bridge sits alongside an existing 150 year old 5-span masonry arch bridge and links the new riverside walks and mooring quays on either side of the river.

The suspended structure is over 100m long in total, connecting into two solid abutments to take the bridge deck to ground level on either side of the river. The new footbridge structure is supported on existing masonry piers and abutments with inclined circular steel struts, to support a slender deck. The 2.6m wide structural deck is made up of box section profiles, tapering from the centre of the deck (at 250mm deep) to the edge (at 100mm deep). The parapets are designed as outwardly curved stainless steel twin plates with tensioned stainless steel wire in-fill. A bespoke extruded aluminium box section deck was required and was designed in conjunction with a specialist international aluminium subcontractor.

For this project, we also employed the services of an expert conservation architect to provide advice on the design issues with regards to the conservation of the visual and architectural heritage amenity provided by the existing stone masonry bridge. This is reflected in the ‘light’ structural form of the new bridge and visibility attached by the choice of an ‘open’ parapet system. Overall, we were responsible for the procurement and supervision of the ground investigation, an options report, detailed design, preparation of Works Requirements and contract administration.