Client: Walls
DBFL are providing civil and structural engineering services for this large-scale residential development at Shanganagh, Shankill, Dublin. The development consists of 597 residential units, a creche, retail and amenity and commercial units, as well as associated site infrastructure works on a c. 9.69ha development site.
The Shanganagh development was the first project to be backed by the Land Development Agency (LDA), which was established by the Government to unlock State land to improve the supply of new homes throughout Ireland. The project is being delivered in partnership with Dún Laoghaire-Rathdown County Council (DLRCC) and will be the largest public housing scheme in the State.
The LDA appointed Walls as the Design and Build contractor for the development with DBFL selected by Walls to carry out the civil and structural design throughout the construction stage.
DBFL are providing structural engineering services including BCAR inspections for the complete development of the 597 residential units, ranging from four to seven storeys. A total of 51 no. two and three storey, detached, semi-detached and terraced houses are proposed and 546 no. apartments. A stand-alone single storey creche also forms part of the site development.
DBFL are also carrying out the main civil engineering and infrastructure design including the following elements including foul and surface water drainage;Sustainable Urban Drainage (SuDS) features; Water Supply; Pavement, road, and junction design; Flood Risk
On this project DBFL worked in a multi-disciplinary team, successfully delivering a phased residential development, with extensive co-ordination with design team members and public bodies to overcome challenges and successfully assess and minimise risks through innovative design as the project progresses.
Soil Stabilisation
Due to poor ground conditions, soil stabilisation and piling were proposed to improve ground conditions.
Soil stabilisation was used under the roads as a capping layer replacement. Stabilising and improving existing soil with cement reduces the requirement to remove spoil off site by converting the weak soils into a usable construction material.
The proposed development was also raised by approximately 200mm to limit excavation and further removal of spoil off site.
One of the key features of the existing site is the existing pond south east of the site. As part of the drainage strategy, the existing pond will be maintained by routing a portion of the surface water runoff through the pond. This is to preserve the existing water level and the ecology of the pond. An overflow is also provided, allowing surface water runoff to bypass the pond in heavy rainfall events to prevent flooding. A petrol interceptor is also located upstream of the pond to filter out pollutants entering the pond. As part of the works, the pond is to be desilted, liaising with Ecologists to protect the environment of the pond.
Precast driven piles were used as part of the foundation scheme for the apartment blocks. Precast piles were chosen as part of the sustainability initiatives to limit the amount of spoil to be removed from site due which would have occurred from pile arisings with conventional CFA piles.
Sustainable Urban Drainage Systems (SuDS) have been incorporated in to the drainage design for the development. Surface water runoff from apartment roofs and creche are captured by green roof prior to being routed to the proposed piped network. Surface water runoff from the houses and duplex units are directed to the proposed pipe network via permeable paving parking to the front and filter drains to the back. Surface water runoff from the internal street network is directed via raingardens, tree pits and other SUDS features. All parking spaces will be captured by permeable paving.
Project Director
