Broadmeadow viaduct

The Broadmeadow viaduct, in Ireland, carries the main Dublin to Belfast railway across the Broadmeadow Estuary, about 13 kilometres north of Dublin, just north of Malahide. It is approximately 180 metres (600 feet) long and it is a section of a longer crossing constructed as an embankment. The viaduct carries around ninety trains, including commuter services and heavy freight, per day and it is the sole rail route between Dublin and Belfast. It has had a history of problems with its foundations being scoured out by strong currents.HistoryThe present structure is the third on this site. The first was built in timber for the Dublin and Drogheda Railway in 1844. Its stability was badly affected by erosion of the river bed around the piles and, after short-term remedial work, it was replaced in 1860 with a new structure of wrought iron spans on masonry piers. This sufficed until the early 1930s when new locomotives (4-4-0 Compounds) required strengthening of the piers and continued maintenance. Additional ballasting of the piers was also needed. The sea air caused deterioration of the wrought iron and these spans were replaced during 1966–1968 with the current prestressed concrete structure. At this time, the tracks were laid on ballast, reflecting modern practice.