Driven in situ piles

1. Whether in the form of a solid pile or a hollow casing , the driving of the pile casing is aided by the use of a driving toe or shoe , often in the form of a pointed cast-iron fitting at the base of the pile to allow easier penetration of the ground .
2. Considerable levels of noise and vibration are generated as a results of the driving operation . Hence they are generally considered unsuitable for congested sites , where adjacent buildings may be structurally affected , or areas where noise nuisance is undesirable .

Replacement piles

1. Installed by removing a volume of soil and replacing it with a load -supporting pile.
2. SOmetimes referred to as bored piles
3. The holes are bored by using a rotary flight auger .
4. As the excavation progresses , the sides are prevented from collapsing by introducing a shell or casing , or by the use of a viscous liquid called , bentorite
5. THe bentonite is then displaced by concrete as it is poured into the excavation and is stored for further use .
6. THis method is more quiet than the displacement method and does not result in damage to surrounding buildings.