What is a Contiguous Bored Pile Wall?
We’re currently preparing to install a contiguous bored pile wall in Blackburn — but what exactly is a contiguous retaining wall, and why might your project need one?
A Contiguous Bored Pile Wall is a form of retaining wall built using a series of closely spaced bored piles. These are installed along the perimeter of an excavation to retain surrounding ground and minimise soil movement, making this method ideal for deep excavations, basement developments, and infrastructure works.
How It Works
- Piles are installed using either the CFA (Continuous Flight Auger) or SFA (Sectional Flight Auger) method, depending on access and headroom.
- A typical gap of 150mm is left between each pile, allowing limited water ingress while maintaining ground stability.
- Reinforcement is used to resist the bending forces once excavation begins.
- A capping beam is cast at the top of the wall, linking the piles to provide overall lateral stability.
Key Benefits
- Ground Retention – Maintains soil integrity during deep excavations
- Cost-Effective – Uses less material than secant walls, though not fully water-retaining
- Versatile – Performs well across a wide range of ground conditions
- Efficient Installation – Faster and easier to construct than alternative methods
Common Applications
- Basement Construction
- Underground Car Parks
- Rail & Highway Cuttings
- Excavations Near Existing Buildings
If you’re planning a deep excavation project and need a robust, reliable solution for ground retention, a contiguous bored pile wall could be the answer.
Contact Dawson Foundation Engineering today for expert advice and tailored retaining wall solutions – or visit dawsonfe.co.uk to learn more about our piling and foundation services.
