Doran Consulting was commissioned to act as Designer on a Design & Build contract for the Roads Service NI in relation to the provision of a footway on both sides of an existing 100 year old twin span masonry arch bridge in Beragh, Co Tyrone. The design comprised a twin span Unreinforced Concrete FlexiArch, on both the upstream and downstream sides, supported on reinforced concrete piers and abutments on mini pile foundations to the underlying rock levels.
As part of the project, we also carried out an independent check of the arch design and foundation loads, followed by detailed design of the reinforced concrete piled abutment solution. This included specialist geotechnical pile design and specification and we then assisted the contractor with their procurement.
As well as the providing design advice in relation to the arch bridge extension itself, we provided input in relation to new wing and retaining walls for all four corners of the bridge, which retained the footways bordering the main road through the village of Beragh.
One of the key requirements of this commission was to produce a design which preserved the aesthetics of the existing masonry arch bridge and was sympathetic to the location in the outskirts of the rural village, whilst achieving a highly durable structure with a 120 year design life. This was achieved by using simple and cost effective FlexiArches to mimic the profile of the existing arches and utilising a local stone cladding finish.