The project involved the deepening and extension of the existing berth at AQE to provide a 320m Lo-Lo facility under a design and build contract.. The design services, provided by Malone O’Regan in conjunction with Malachy Walsh & Partners, comprised the assessment of existing structures, the design of a new concrete-faced quay wall with capping beam; design of quayside furniture including storm moorings, bollards, ladders and fendering system; design of terminal infrastructure including concrete crane beams, pavement for container storage, electrical services including lighting, reefer gantry and supplies for future cranes, water supply and drainage. One of the first capital projects carried out in the development programme was the deepening of the berth at Alexandra Quay East (AQE) to -11mCD to accommodate container vessels of up to 2,400TEU.
The key challenge was to minimise disruption to the operation of the existing Lo-Lo terminal. Design options were developed to limit excavations in the terminal area to those required for construction of the crane beam and the new quay wall was anchored to crane beam through the concrete pavement thus avoiding an anchor wall and tie rods. Temporary mooring bollards were installed, and the construction works phased so that one ship could be accommodated at the berth right through the construction period. The existing quay structure comprised of large concrete caissons founded at a shallower than the future dredge depth. Previous experience in Dublin Port suggested that the caissons would rotate as the new combi-wall was constructed in front of them, so it was necessary to develop a detailed understanding of the caisson structures and how it would work in combination with the new quay wall.