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Installation of Piles

Driven piles: by hammers or vibratory drivers.

Bored piles: piles can be inserted by jetting or
partial augering.

Continuous Flight Auger (CFA)

1. Driven piles

• Driven piles are displacement piles, because they
move some soil laterally; hence, densify the soil
surrounding them.

• Concrete piles and closed-ended pipe piles are large-
displacement piles. However, steel H-piles displace
less soil laterally during driving, so they are low
displacement piles.

• The types of hammer used for pile driving include:

 drop hammer,

 single-acting air or steam hammer,

 double-acting and differential air or
steam hammer, and

 diesel hammer.

Drop hammer (Figure 7a)

• Hammer is raised by a winch and allowed to
drop from a certain height H.

• It is the oldest type of hammer. The main
disadvantage of the drop hammer is its slow rate
of blows.

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