Bored piles are reinforced concrete elements cast into drilled holes, used to transfer heavy loads to a deeper competent soil or rock stratum. Bored piles, executed in a low-vibrating continuous drilling method, can be used for foundations and pit securing as well as for slope stabilization. Secant pile walls (separeted, tangent or overlapped) are seen as relatively stiff and low-deforming systems. The execution can be done in almost all soils due to the use of adapted drilling tools.
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.
CFA Piles are constructed by rotating a continuous flight hollow stem auger into the soil to aspecified depth. Concrete or grout is pumped through the hollow shaft to fill the cylindrical cavity created as the auger is slowly withdrawn.
- High production levels are attainable in suitable soil conditions
- The system is economical in suitable soil profiles
- Noise levels are low
- There is no vibration associated with CFA piles