CFA Piling
Pictures
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Keller's Augercast Continuous Flight Auger (CFA) piling system provides a quiet low vibration form of piling that is ideal in built-up areas.
Keller's CFA rigs can construct piles in most soils including sands, gravels, silts, clays, chalk and weak bedrock, in high water tables without the need for temporary support systems.
Instrumentation
Constant monitoring is essential to the success of the CFA system.
Keller's sophisticated in-cab instrumentation allows the monitoring of the movement and position of the auger digging head as well as the rate of flow, amount and pressure of concrete delivered during formation of the pile shaft.
Reinforcement
The reinforcement cage has to withstand the rigours of placement through the recently pumped high slump concrete.
Typically, Keller Augercast Bored Piles are reinforced with a rigid six metre long cage as a minimum. However, there is the ability to install much longer cages as and when required by the design or specification. A specially developed vibrator unit assists with the placing and accurate location of the reinforcement cages.
Concrete cover is afforded to the reinforcement by the effective use of Keller's 75mm plastic 'sledge' spacers clipped onto the main bars.
Enlarged Head CFA Piles
When CFA piles are required to support floor slabs or loads from embankments etc. the connection would traditionally be made through a pile cap or network of ground beams. With the Keller CFA system however, the piles can be installed with insitu, enlarged heads of predetermined diameter (typically around 900mm). This innovative approach can save considerably on slab reinforcement and the cost/time involved in trimming pile heads
