Page 12 - GDL - EARTHWORKS GROUND IMPROVEMENT PILING

CFA PILING
CFA (Continuous Flight Auger) piles are quick to install and they offer an ef cient solution for more lightly-loaded structures.
Using our CFA rigs, we can offer the best and most cost-effective solution for our clients’ projects across the UK. Our knowledge and expertise, as well as our experienced site team and on-board technology, means that we can monitor quality and performance real-time.
CFA technology offers the ideal solution for projects in urban locations because it eliminates vibration and disturbance to adjacent structures, and it reduces noise emissions.
Continuous CFA piles are suitable for most soil conditions and construction projects. They are the best and most effective solution when piling is required close to existing buildings, or in built-up areas because this piling approach is virtually vibration free, and it has low noise levels.
CFA Drilling technique: Continuous ight auger piles are constructed rotating an auger string into the ground by injecting concrete under a minimum pressure through the hollow stem of the auger. The soil is replaced with concrete in one continuous movement as the auger is withdrawn. After the pile head is cleared of debris, steel reinforcement is plunged into the pile concrete.
The technique requires no additional ground support, such as casing or drilling uids, because the bore is self-supporting as the auger is rotated into the ground and the concrete supports the bore after extraction.
Ground conditions: CFA piling is amenable to a broad range of ground conditions from medium dense sands and gravels through to stiff clays and even low grade rock. The technique is not recommended
in very soft clays or silts or in very loose sands or gravels.
Advantages of CFA Piling:
• High production rates mean that piles are commercially attractive
• Broad range of auger sizes (300mm to 1200mm diameter) means that the most economical use of construction materials is possible
• Depths of up to 25m means that CFA piling is effective for low to mid-range loading thus suitable for most commercial and residential projects
• Low noise emissions
• Virtually vibration free