2020
Bangor, CO Down
Crawfordsburn Construction
P G Contracts
Alan Cooke Architects
Reinforced Soil Retaining Solution in Crawfordsburn
Challenge
Maccaferri was appointed by PG Contracts to design and deliver a sustainable retaining wall solution for a residential development in Crawfordsburn, Bangor, County Down, Northern Ireland. The project required soil retention of up to 5 metres in height to allow existing ground levels to be raised, enabling increased garden space for newly constructed homes.
A major constraint on the project was the site’s proximity to Crawfordsburn Glen, a popular off-road pedestrian walkway that runs alongside the Crawfordsburn River and connects to Crawfordsburn Forest Country Park. As the retaining structure would run parallel to this environmentally sensitive and highly visible area, it was essential to implement a solution that combined structural performance with a natural, vegetated appearance. The client required a “green face” retaining system that would seamlessly integrate with the surrounding landscape and minimise visual impact.
Solution
Maccaferri proposed a Green Terramesh Reinforced Soil Slope system, an engineered solution designed to provide both structural stability and an environmentally friendly finish. The system was selected for its ability to deliver a vegetated retaining wall that blends into natural surroundings, making it ideal for projects near public pathways and green spaces.
The reinforced soil slope extended approximately 70 metres in length and reached a maximum height of 5 metres. Structural integrity was achieved using ParaGrid 50/05 geogrid reinforcement, installed in layers between compacted backfill. These geogrid layers were designed to bespoke lengths to suit the specific geometry and loading conditions of the site, ensuring optimal performance and long-term stability.
A key benefit of the solution was the use of site-won backfill material. Following on-site testing, it was confirmed that locally sourced material met the required specifications, eliminating the need for imported fill. This significantly reduced project costs and lowered the environmental impact associated with transportation and material sourcing.
After installation of the Green Terramesh units, topsoil was placed behind the front face and seeded. Over time, vegetation established across the slope, creating a durable green façade. The finished reinforced soil slope not only met the engineering requirements but also delivered a sustainable, aesthetically pleasing retaining solution that harmonised with the surrounding natural environment.
Used Products
