Projects | Bridges

Mary McAleese, (Boyne) Bridge

This landmark structure was brought through the entire planning process including Feasibility Stage, Preliminary Design, Public Consultations, Presentations to three Local Authorities, Motorway Enquiry, Detailed Design, development of procurement strategy and construction supervision by ROD.

It consists of a 350m long, cable-stayed, high level bridge carrying the M1 Northern Motorway (Dublin-Belfast) across the River Boyne to the west of Drogheda. It is the largest bridge project in this country in recent decades and consists of an asymmetrical cable-stayed bridge with an overall length of 370 metres and spans of 42. 5, 170.0, 40, 45.0, 30.0 and 25.0 metres.  The 35 metre wide deck comprises two longitudinal steel plate girders with transverse girders at 3.333 metres centres supporting an insitu reinforced concrete slab.  The steel composite deck which will remain unpainted is clad in a GRP enclosure.  The deck is supported from a 95 metre high reinforced insitu concrete pylon by 14 pairs of stay cables.  Each stay cable consists of between 32 and 68 No. 15.7mm diameter 7-wire strands.  A significant part of the bridge design is the architectural lighting scheme which illuminates the structure at night.

This bridge was awarded both the IEI Morgan Sheehy Medal and the ACEI President’s Award from the Association of Con sulting Engineers of Ireland (ACEI).