Civil Engineering Reference
In-Depth Information
TYPES OF BEARING PILE
DISPLACEMENT
NON-DISPLACEMENT
Grout-intruded
CFA
Concrete-intruded
CFA
AUGER SCREW PILES
TOTALLY PREFORMED
DRIVEN CAST-IN-PLACE
BORED CAST-IN-PLACE
An auger is screwed into the
ground and retrieved during
concreting
A section, tubular or otherwise, is
driven (or screwed) into the ground.
The section is:
A tube is driven into the
ground to form a void.
The tube is:
A bore is formed by means
of a hollow-centered continuous
flight auger. Grout is intruded
and either displaces or
mixes with the bore spoil.
A bore is formed with a
hollow-stemmed continuous
flight auger. Concrete is
pumped through the stem
as the auger is extracted to
displace the bore spoil.
A bore is formed in the
ground and may be partially or
fully supported by steel casing
or support fluid (mud)
VCC
Hollow
Solid
The bore is:
Steel
Concrete
Concrete
Steel
Timber
Concrete
Steel
A vibroflot is inserted
into the ground to the
required depth
displacing the soil
Percussion bored
Rotary bored
Drilled
Pre-cast reinforced
Pre-cast pre-stressed
The closed-ended tube is filled
with concrete and left in position
The tube is:
Large diameter
Small diameter
Closed-ended
Open-ended
Underreamed
cast-in-place
(generally large
diameter)
Preformed units are
grouted in place
(partially pre-formed pile)
Joined using a
proprietary system
Joined by splicing
Straight-shafted
cast-in-place
The tube is left in position and
filled with concrete.The tube is:
1) of constant cross section
2) of tapered cross section
The basic system comprises
driving a retrievable tube and
forming a pile with or without
an enlarged base.
By back-screwing to leave a
helical (screw) shafted pile formed
by grout or concrete intrusion via
the auger stem
Straight retraction to leave a full
diameter cylindrical shafted pile
by grout or concrete intrusion via
the auger stem
Concrete is introduced down
the vibroflot stem as it is
withdrawn. An enlarged base
can be formed.
