A Beginner’s Guide to CFA Piling

09 Feb A Beginner’s Guide to CFA Piling

When you need to construct piles for medium to high load buildings CFA Piling is quick and economic. Also known as augered cast in place piles (ACIP) or screw piles, this method of casting in-situ is particularly suitable for granular and wet soil conditions and has been around in the UK since the 1960s.

CFA piling is low vibration and useful for works near existing buildings or on environmentally sensitive sites. It’s an effective form of underpinning when you need to create stable foundations in unstable soil conditions.

CFA stands for Continuous Flight Auger and is one of the quietest, fastest and most economic methods of underpinning available. Unlike mini piling, CFA piles are cast in-situ with high-quality concrete pumped into the auger’s hollow stem.

Known as a non-displacement process because the soil is brought to the surface, CFA piling is quite straightforward. The auger is drilled into the ground up to the required depth. Then the concrete is poured and the auger rotates to extract itself from the hole taking the ground material with it. Once the concrete reaches ground level a steel reinforcement cage is immediately inserted eliminating cutoffs and splices.

CFA piling is suited to a range of groundworks on strata including silt, clay, gravel and sand or where there’s a high groundwater table.

They can be constructed as single or multiple piles similar to driven foundations. They’re a smart choice when speed and minimal noise and vibration impact are critical or where there’s restricted site access.

They’re commonly used for large scale infrastructure projects including bridges, tunnels and road construction as well as providing flood protection.Other uses include large structural foundations and multi-storey buildings.

This type of piling system has a wide range of benefits:

– Quick and cost-effective
– Suitable for most soil conditions
– Achieves depth ranges of between 18m and 32m with diameters between 300mm and 1500mm
– No temporary casings are required in unstable soils
– Low levels of disruption

Installation of CFA piling requires constant quality monitoring for the best results. At BSB Concrete Formation Services we offer a full range of groundworks services including CFA piling and mini piling plus a full range of ground beams and constructor services. Contact us today and we’ll help you find the best underpinning solution for your next project.