Bridge over River Erne in Ireland

Abstract

The extradosed bridge over the River Erne was required as part of the proposed N3 road improvement project in Cavan, Ireland. The structure is a three span concrete continuous bridge (36,2 m + 69,5 m + 36,2 m) with extradosed and bonded prestressing, resulting in a relatively slender deck with a curved soffit and quadratic voids. The maximum depth of the deck is 1,525 m at the centerline, with a total width of 17,1 m. A saddle, by means of friction, allows every extradosed cable to cross through the pylons. Both halves of the bridge were constructed from their corresponding side of the river with the help of a scaffolding over a temporary península. The conceptual design was carried out by Roughan & O'Donovan for the Cavan Council and The National Roads Authority of Ireland, and the detailed design was developed by Ferrovial-Agromán's. The Design Code was the Eurocode with the Irish National Annex.