Continuous flight auger (CFA) piling is an affective and versatile method of piling for a wide range of ground conditions and soil types including:
- Sand
- Gravel
- Weaker rock
- Silts
- Clay
Because of its versatility and effectiveness, augered piling has become one of the most popular methods of piling used in the UK today.
CFA methods are also adopted for a range or piled embedded wall solutions, such as King Post, Contiguous and Secant piled retaining walls.
Contact our expert piling team/engineers for advice on your project and get a no obligation quote
What We Offer
- Free site visits
- Free no obligation quotes
- 12 Year warranty of all work
- Estimates based on detailed tender stage designs
The CFA Piling Process
The process of forming a CFA pile is completed in one continuous operation, using instrumented piling rigs to monitor the pile construction process in real time as the auger is progressed to depth, and whilst concrete is being placed.
The CFA piling method is fast and efficient, generating low levels of noise, and is virtually vibration free.
From start to finish, what is the process of CFA piling?
Step 1 – Prior to the rig arriving to site the client surveys the area for services, prepares a suitable working platform at top of foundation level, and drives a numbered pin into the working platform at each pile position.
Step 2 – A health and safety briefing will take place, the rig will be prepared to work, and moved to the first pile position.
Step 3 – The auger is positioned over the setting out point and zeroed at working platform level. The auger is then progressed to a predetermined designed depth, pausing occasionally to bring spoil to the surface.
Step 4 – Readymix concrete will be delivered to site and pumped to the rig using a system of hoses connected to the top of the auger. The rig operator begins extracting the auger string, ensuring a constant head of concrete is maintained within the auger to avoid the risk of borehole collapse during construction. This process is fully computerised in CFA rigs, providing the rig operator a continuous profile of pile diameter during auger extraction.
Step 5 – The attendant excavator clears spoil from piling mat level, exposing the fresh concrete at the head of the pile.
Step 6 – A reinforcement cage, meeting the design requirements, is plunged into the fresh concrete, to provide fixity between the piles and reinforced concrete foundations.
When is CFA Piling used?
CFA piling is widely used on projects ranging from residential housing, commercial development & refurbishment, to large scale civil engineering projects, and many more. They are equally suited to piled raft slab and traditional ground beam and pile cap applications. In addition to the construction of bearing piles, CFA piling methods are equally well suited to the construction of contiguous, secant and king post embedded piled retaining walls.
Using our CFA rigs, equipped with pull down/crowd function and rock augers, it is possible to install CFA piles through Weak Rock formations, avoiding having to revert to more expensive percussive drilling or rotary bored piling methods.
To get a better understanding of when CFA piling is used, check out our case studies pages.
Our Piling Rigs
Our rigs are equipped with on-board instrumentation systems to ensure high quality pile construction and record keeping.
Our current augered piling fleet consists of:
CFA
- Comacchio CH 450
- Soilmec SR30
- Soilmec R312
- Geax EK110
- Geax EK75
SFA
- Hutte HBR204
- Hutte HBR203
You can find out more about our rig collection on our fleet page.
Our Testimonials:
We have always found GeMech to be professional, straight talking and a pleasure to work with.
Simon Blackledge, Commercial Director, Gr8Space Group
GeMech handle all aspects of our ground improvement projects together with transparency and professionalism.
Darren Faircloth, Faircloth Construction Ltd
GeMech have always been courteous, knowledgeable and honest throughout our dealings with them.
Charlie Barker, Deep Living London Ltd
I have always found all members of the GeMech team to be extremely customer focused, technically proficient and totally driven to provide the best possible service and quality on site.
James Sinclair, Blue Dot Construction
In a competitive market GeMech has always stood above the competition as an exceptional ground improvement solution provider.
Daniel Calnan, Kent Structures
We have worked with GeMech on a number of projects, both complex with restricted access and large housing schemes. They have always been pro active providing solutions and costings. They have delivered all of our schemes to programme.
John Reed, Capstan
Clear, professional & practical communication during the pre-construction phase allowed for a smooth operation on site. Correct methods of piling for the presenting ground conditions were discussed and employed, resulting on hitting programme targets aswell as budget constraints.
James Scott, Willmott Dixon
Talus Solutions Ltd enjoys a harmonious relationship with the team at Ge-Mech Ltd, working together on various industrial, commercial and private sector housing projects. We have found Ge-Mech to be dependable and competitively priced in what they do and always ready to assist.
Philip Halford, Talus Solutions Ltd
Having worked with Gemech for over 20 years, they have always provided a first class engineered solution for our schemes.
Julian Mitchell, Mitchell Design & Construction
From start to finish the GeMech team take care of everything from the initial design to bringing each project to a successful conclusion on site.
Mark Blackhurst, Barnack Estates UK Ltd
Capabilities:
- Pile diameter 300mm – 900mm
- Maximum depth 25.0m
- Working loads up to 3,300kN
