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7/30/2019 [FRANKI] Displacement Piles
1/18
Sydney (Head Ofce)
Level 1, 4 Burbank Place
Baulkham Hills NSW 2153 Australia
T: +61 2 8866 1100 F: +61 2 8866 1101 Email: australia@franki.com.au
DISPLACEMENT PILES
This pile type is similar to the Atlas pile with the exception that
most displacement piles are straight shafted as opposed to the
helical shafts on the Atlas piles. These piles are installed using
modern, very high torque hydraulic drilling rigs which rotate
a specialised displacement tool into the ground. The action of
the specially designed tool causes the ground to be compacted,
when the tool has reached the required depth it is withdrawn
whilst concrete is pumped out through the hollow stem.
The installation process of both types is totally vibration free but
the major advantage is that the process produces no spoil with, theexception of minor ground heave, thus obviating the need to deal with
any contaminated spoil.
ATLAS PILES
The Atlas pile is a unique screw shaped reinforced concrete
pile design to take maximum advantage of all the available soil
capacity by displacing the soil rather than replacing it.
The Atlas pile is a concrete cast in-situ and is not to be confused with
the steel screw pile which has much lower load carrying capacity. The
piles can be installed with a conventional purpose built Atlas rig or
the new generation high torque hydraulic piling piles allowing pilesup to 30m to be installed in a single pass. As these piles are genuine
displacement piles with the auger being thrust into the ground with
a minimum of 40 tonne metre torque negligible spoil is produced for
subsequent removal, very important consideration when piling in
contaminated or aggressive soils.
DISPLACEMENT PILES
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2/18
Sydney (Head Ofce)
Level 1, 4 Burbank Place
Baulkham Hills NSW 2153 Australia
T: +61 2 8866 1100 F: +61 2 8866 1101 Email: australia@franki.com.au
CONTINUOUS FLIGHT
AUGER (CFA) PILES
LOAD CAPACITY
CFA Piles are most suited or use in sands with load capacity
developed in both adhesion and end bearing. The designresistance may be calculated using conventional static pile
design theory with design parameters relevant to non-
displacement piles.
The pile founding depths should be predetermined before installation
from a site investigation report.
This pile type is also suited for use in rock with available equipment
able to form sockets in weak to medium strong rocks. CFA piles are not
normally viable in lower strength clays, unless a suitable end-bearinglayer is available to found in.
CONTINUOUS FLIGHT
AUGER (CFA) PILES
The CFA Pile is a non-displacement pile used where ast
vibration ree installation is required in difcult ground
conditions. The drilling process is suitable or penetrating
dense layers and is unaected by ground water or collapsing
soil conditions.
The pile is formed by rst drilling into the ground with a continuous
ight auger.
Cement-sand grout or concrete is then injected under pressure through
the augers hollow stem as it is being withdrawn.The grout or concrete pressure is maintained during the auger
withdrawal so that it assists the extraction as well as exerting a lateralpressure on the surrounding soils. On completion of this operation, a
reinforcing cage is placed into the uid column of grout or concrete.
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Sydney (Head Ofce)
Level 1, 4 Burbank Place
Baulkham Hills NSW 2153 Australia
T: +61 2 8866 1100 F: +61 2 8866 1101 Email: australia@franki.com.au
FRANKI PILES
FRANKI PILES
Although the Franki pile is generally installed by bottom
driving, highly special techniques such as open-ended coring,
rock socketting, and composite shaft construction are used in
particular situations to overcome unique site problems.
It can safely withstand very high compressive and tensile forces and
substantial horizontal loads.
The installation process of each Franki pile takes account of the soilconditions at each pile location. Quality control checks on the driving
and basing resistance of every pile result in optimum pile performance.
The pile is always sealed during construction. Ground water or
collapsing ground present no problems.
Noise and vibration levels are minimised as a result of Frankis uniquebottom driving technique.
Because the impact occurs at the bottom of the tube, the
Franki pile is the quietest of the driven cast-in-place systems and is
suitable where high noise levels would cause environmental problems.
Vibration levels are monitored regularly and in most ground conditionscan be kept below the strictest international standards.
These features have helped make the Franki pile the most popular cast-
in-place pile in Australia for more than 50 years.
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Sydney (Head Ofce)
Level 1, 4 Burbank Place
Baulkham Hills NSW 2153 Australia
T: +61 2 8866 1100 F: +61 2 8866 1101 Email: australia@franki.com.au
THE FRANKI BASE & SHAFT
The action of forming an enlarged base improves and
strengthens many soil types. Also the pile base can be enlarged
up to three times the shaft diameter resulting in a shorter more
economical pile which has superior settlement performance
when compared to a straight shaft pile.
Where high tension loads are required, the reinforcement can be
anchored into a tension base giving signicantly increased tension
resistance.
The load capacity and settlement analyses of Franki piles are calculated
using displacement pile parameters with design methods based on
many years of research and thousands of test pile results in a widerange of ground conditions. Theoretical expectations are conrmed
during construction by monitoring the dynamic resistance of the piling
tube and the energy requirements for forming the enlarged base. The
pile type can be constructed in practically all soil conditions.
FRANKI PILES, cont
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5/18
Sydney (Head Ofce)
Level 1, 4 Burbank Place
Baulkham Hills NSW 2153 Australia
T: +61 2 8866 1100 F: +61 2 8866 1101 Email: australia@franki.com.au
BORED PILES
Large diameter bored piles are non displacement piles which
are commonly used where large vertical loads or bending
moments must be carried by a single unit.
Bored piles founded in rock provide an effective means of minimising
foundation settlements and a small number of high capacity bored
piles can often provide signicant savings in pile cap costs over other,
lower capacity, pile types.
Being non displacement type piles, bored piles can be installed with little
or no vibration, and with much lower noise levels than driven piles.
Franki has a large range of equipment available for the execution of
bored piles ranging from limited headroom equipment to modern allhydraulic tracked machines capable of drilling holes in soil and rock.
Soil and or rock is removed using purpose designed drill tools including
soil and rock augers, drilling buckets, core barrels, and down hole
hammer drills. Drilling to depths of up to 60 meters and to diameters
from 300mm to in excess of 2 metres is possible in soil and rock.
Various methods of support for the sides of bored piles duringconstruction are available. These can be selected to suit the type of
formation being drilled, the ground water regime encountered, and site
environmental constraints.
BORED PILES
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Sydney (Head Ofce)
Level 1, 4 Burbank Place
Baulkham Hills NSW 2153 Australia
T: +61 2 8866 1100 F: +61 2 8866 1101 Email: australia@franki.com.au
BORED PILES, cont
Shaft support methods available include:
* Vibrated temporary casing.
* Drilled temporary casing.
* Oscillated temporary casing.
* Permanent liners.
* Drilling under water.
* Drilling under bentonite.
* Drilling under polymer uids.
The load capacity of bored piles is a function of the geotechnicalcapacity of the pile, the installation technique chosen, and the
structural capacity of the pile shaft. The capacity of piles socketed into
good quality rock is often limited by settlement considerations. Bored
piles are also particularly suited to providing resistance to high lateral
loads such as those induced by wind loading and earth quake loading.
In these circumstances the larger diameters available, combined withheavy steel reinforcement cages if required, provide the required
structural strength.
In very hard rock, bored piles can be constructed using down the hole
hammer drills or roller cutter core barrels. These techniques allow
the drilling of hard and abrasive rocks which would otherwise be verydifcult to penetrate economically with conventional
drilling equipment.
In some circumstances, belling techniques may prove economical to
take advantage of high end-bearing resistance. Typical bell diameters
of up to 2 times the shaft diameter can be constructed by
mechanical means.
The actual load capacity of bored piles can be veried by static
geotechnical calculations, by logging of shafts during drilling, by static
or dynamic load testing, or by Statnamic load testing which provides
an economical means of testing to high load levels.
BORED PILES, cont
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7/18
Sydney (Head Ofce)
Level 1, 4 Burbank Place
Baulkham Hills NSW 2153 Australia
T: +61 2 8866 1100 F: +61 2 8866 1101 Email: australia@franki.com.au
PILES IN RESTRICTED AREAS
Franki has the equipment and expertise to construct piles
in restricted areas with a minimum of noise and vibration
including areas with head room as low as 2.4 metres.
Where access is a problem, Franki offer:
* Bored piles and groutcrete piles up to 500mm diameter.
* Forum piles, the original enlarged base piles for maximum load inconned areas.
* Tube piles for areas where ground water is a problem.
The product used depends on the load requirements and conditions.The equipment used is based on either the Franki mini rig, or the
traditional tripod rig.
Applications include:
* Underpinning.
* Renovations to existing structures such as shops, railwaystations, etc.
* Bridge extensions in awkward locations.
The traditional Forum pile system can be disassembled to allow access
to normally inaccessible areas.
The base of the Bawang pile is expanded to increase pile load capacityafter the pile has reached the required depth.
PILES IN RESTRICTED AREAS
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Sydney (Head Ofce)
Level 1, 4 Burbank Place
Baulkham Hills NSW 2153 Australia
T: +61 2 8866 1100 F: +61 2 8866 1101 Email: australia@franki.com.au
DRIVEN PRECAST PILES
The Franki precast pile is a high strength high capacity precast
concrete pile which incorporates mechanical and compression
joints, allowing piles to be spliced quickly and then driven to
any required depth.
Precast piles offer the geotechnical efciency of a driven pile with the
economies of a mass produced product. A rigorous quality assurance
program throughout the casting, driving and testing process ensures aconsistently reliable product with high strength and durability. Precast
piles are most suited to ground conditions where soft upper strata
overlie a hard bearing layer and in areas with clay or silt deposits.
Franki maintains its own casting facilities which enables it to cater for
varying site conditions with a range of stock pile lengths & sizes.
Franki maintains in house casting capacity sufcient to customise pile
lengths for individual sites and to cater for site variability without the
need for long casting periods prior to job commencement.
DRIVEN PRECAST PILES
THE PILE JOINT
Franki has two main types of pile joint:
1. The compression sleeve - an economical join used when there are no
tension loads or high movements on the pile.
2. A mechanical joint - Which is cast into the piles and consists of a series
of pins and recesses that are mated during the pitching process andare then held in place by the inserton of high strength steel wedges.
The mechanical joint is designed and proof tested to ensure that where
necessary the compression, tension and bending stresses are similar
to that of the pile section.
LOAD CAPACITY
Franki precast piles are manufactured from high strength concrete usingstate of the art technology. Structural load capacities are based on an
independent testing and research program.
Piles are driven using the most sophisticated piling machines operating
in Australia. These are equipped with efcient hydraulic hammers for
faster installation and lower pile stresses during driving.
The geotechnical strength and serviceability are determined usinganalytical methods applicable to displacement piles and parameters
based largely on intensive static and dynamic load test results.
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Sydney (Head Ofce)
Level 1, 4 Burbank Place
Baulkham Hills NSW 2153 Australia
T: +61 2 8866 1100 F: +61 2 8866 1101 Email: australia@franki.com.au
Pictured above: Piled foundations for silos at the casting basin, Tempe
NSW, used in the construction of the underground rail link to Sydneys
Mascot airport
Frankipile also supply and drive other types and preormed
piles such as:
* pre stressed octagonal piles
* steel bearing piles
* steel sheet piles
* steel tube piles
DRIVEN PRE-FORMED
TIMBER PILES
Timber was the frst material to be used in piling work and was
the only material used or this purpose or many centuries.
Timber is popular in Marine applications as it is a tough resilient
material which can absorb considerable shock without serious damageby such incidents as collision. They are also more easily repaired than
steel or concrete piles.
Timber is renowned for its inertness and as such has the natural ability
to perform its task long term in hostile chemical soil conditions. The
availability of modern timber preservation technology has increased
this popularity of timber piles in chemically aggressive soils. It isideally suited to applications where an economical pile is required to
carry small axial loads.
Frankis eet of Driving rigs are well suited for the fast and economical
installation of timber piles both on land and also in marine applications.
DRIVEN PILES
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11/18
Sydney (Head Ofce)
Level 1, 4 Burbank Place
Baulkham Hills NSW 2153 Australia
T: +61 2 8866 1100 F: +61 2 8866 1101 Email: australia@franki.com.au
SECANT PILE WALLS
RETAINING WALLS, cont
SHEET PILE WALLS
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Sydney (Head Ofce)
Level 1, 4 Burbank Place
Baulkham Hills NSW 2153 Australia
T: +61 2 8866 1100 F: +61 2 8866 1101 Email: australia@franki.com.au
RETAINING WALLS, cont
PREFABRICATED WALLS
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13/18
Sydney (Head Ofce)
Level 1, 4 Burbank Place
Baulkham Hills NSW 2153 Australia
T: +61 2 8866 1100 F: +61 2 8866 1101 Email: australia@franki.com.au
Dynamic LoaD TesTing
D ld tt (DLT) hh tr tt thd fr
pl prfr. ovr th lt 15 r, t h b
th prdt f pl ld tt wrldwd. DLT
vlv pt th hd f pl wth pl hr
r drp wht d ur th rultt tr d
lrt. Th urt r ud t qutf th
pl d l bhvur rp t th ppld d
fr. s prtt pblt f th DLT thd r
urd fllw:
* Relatively quick and economical means of quality control for pileconstruction.
* On-site monitoring of piling hammer performance.
* Assessment of driving problems and/or pile damage.
* Provides immediate estimate of mobilised pile resistances during
the blow.
* Can be applied to all types of pile foundation.
While originally developed for driven piles, the DLT method has beensuccessfully transferred to the testing of cast-in-place piles. DLT, when
applied to pre-formed driven piles, is a powerful diagnostic tool to
control and identify problems in the pile driving process.
DLT is carried out using either the Foundation Pile Diagnostic System
(FPDS), manufactured by the TNO Building and Construction Research
Organisation in the Netherlands or the PAK System, manufactured byPile Dynamics, Inc. of the USA. Both systems comprise a portable eld
computer with signal processing electronics, a signal conditioning
system, two strain gauge/acceleration transducers, together withsoftware for monitoring and reporting.
DYNAMIC LOAD TESTING
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Sydney (Head Ofce)
Level 1, 4 Burbank Place
Baulkham Hills NSW 2153 Australia
T: +61 2 8866 1100 F: +61 2 8866 1101 Email: australia@franki.com.au
DYNAMIC LOAD TESTING, cont
The analysis is carried out using the signal matching program
CAPWAP. Pile and soil data are modelled and a response is ca
lculated based on one dimensional wave equation theory. The signal
matching process utilises an iterative method in which the results of
each analysis are compared to the actual measured pile behaviour.Appropriate dynamic soil parameters are rened until a satisfactory
match is achieved. The mobilised static shaft and toe resistance of the
pile can hence be derived. The signal matching program also provides
a prediction of the static load displacement performance of the pile on
the basis of the rened pile and soil model.
HoW Does iT WoRK?
Dynamic load testing is carried out with two identical bolt-on strain andacceleration transducers attached to a section of pile. The pile is then
struck with a driving hammer or a separate drop weight. A hammermass of about 1 to 2% of the test load is generally sufcient. The
generated compressive stress wave travels down the piles and reects
from the pile toe upward. The stress waves, which are picked up by the
transducers, are processed and automatically stored in the computer
for further analysis and reporting.
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Sydney (Head Ofce)
Level 1, 4 Burbank Place
Baulkham Hills NSW 2153 Australia
T: +61 2 8866 1100 F: +61 2 8866 1101 Email: australia@franki.com.au
Static Load teSting
th s l s (SLt) vlvs h r msurm
pl h splm h rsps physlly ppl
s l. i s h ms uml rm pl l s
s sr s h bh-mrk pl prrm. ts
hs b prrm h l r 100kn 12,000 kn. th
SLt my b rr u r h llw l furs:
* Compression
* Lateral
* Tension (i.e. uplift)
For the SLT the load is most commonly applied via a jack actingagainst a reaction beam, which is restrained by an anchorage system
or by jacking up against a reaction mass (kentledgeor dead weight).
The anchorage system may be in the form of cable anchors or reaction
piles installed into the ground to provide tension resistance. The
nominated test load is usually applied in a series of increments in
accordance with the appropriate Code, or with a pre-determined loadtesting specication for a project. Each load increment is sustained for
a specied time period, or until the rate of pile movement is less than a
nominated value.
Static load testing methods are applicable to all pile types, on land
or over water, and may be carried out on either production piles or
sacricial trial piles. Trial piles are specically constructed for the
purpose of carrying out load tests and therefore, are commonly loaded
to failure. Testing of production piles however, is limited to prove that apile will perform satisfactorily at the serviceability or design load, plus
an overload to demonstrate that the pile has some (nominated) reserve
capacity.
tHe teSt PRocedURe
Loading is applied to the test pile using a calibrated hydraulic jack, and
where required a calibrated load cell measures the load.
During the SLT, direct measurements of pile displacement under the
applied loading are taken by reading deectometers (dial gauges
reading to 0.01mm) that are positioned on glass reference plates
cemented to the pile head. The deectometers are supported by
reference beams that are founded a specied distance away from boththe test pile and any reaction points.
Although SLT is generally held as the most reliable form of load
testing a pile or pile group, it is important that interaction effects areminimised. These may result from interaction between the test pile and
the anchorage systems, or between the measuring system and reaction
points. For this reason, careful attention is given to performing the test
in accordance with proper procedures.
teSt ReSULtS
Test results are presented inconventional graphical format showing the
applied load versus pile head displacement.
STATIC LOAD TESTING
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Sydney (Head Ofce)
Level 1, 4 Burbank Place
Baulkham Hills NSW 2153 Australia
T: +61 2 8866 1100 F: +61 2 8866 1101 Email: australia@franki.com.au
STATIC LOAD TESTING, cont
The analysis is carried out using the signal matching program
CAPWAP. Pile and soil data are modelled and a response is ca
lculated based on one dimensional wave equation theory. The signal
matching process utilises an iterative method in which the results ofeach analysis are compared to the actual measured pile behaviour.
Appropriate dynamic soil parameters are rened until a satisfactory
match is achieved. The mobilised static shaft and toe resistance of the
pile can hence be derived. The signal matching program also provides
a prediction of the static load displacement performance of the pile on
the basis of the rened pile and soil model.
HoW doeS it WoRK?
Dynamic load testing is carried out with two identical bolt-on strain andacceleration transducers attached to a section of pile. The pile is then
struck with a driving hammer or a separate drop weight. A hammermass of about 1 to 2% of the test load is generally sufcient. The
generated compressive stress wave travels down the piles and reects
from the pile toe upward. The stress waves, which are picked up by the
transducers, are processed and automatically stored in the computer
for further analysis and reporting.
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17/18
Sydney (Head Ofce)
Level 1, 4 Burbank Place
Baulkham Hills NSW 2153 Australia
T: +61 2 8866 1100 F: +61 2 8866 1101 Email: australia@franki.com.au
Sonic integrity teSting
th s s (Sit) s a -dsuv s f
qukl ad mall hk h u f
a salld pl fuda. th mhd s fd as a lw-
sa s ad s ul usd f qual l pupss
pl pjs.
SIT can be applied to cast-in-situ piles and pre-formed driven piles
(concrete, steel, timber). The test will detect pile defects like cracks, voidsand soil inclusions, changes in the pile diameter (e.g. necking), and
major variations in the consistency of the pile material. The method does
not provide any information on the load bearing capacity of the pile.
The equipment used for SIT is robust and portable and comprisesa light-weight eld computer, transducer, connecting cables and a
plastic mallet. Thus, any accessible pile can be tested by a single
operator. An experienced operator can test up to 100 piles per day in
ideal conditions. In most cases, the experienced operator can provide
immediate on-site interpretation of the test result.
PHenoMenA DetectABLe
* Reections from the toe, (in most cases).
* Reections from signicant inclusions (5-10% or more of the pile
diameter).
* Reections from horizontal cracks.
* Reections from joints, (as for precast concrete piles).
* Reections from increases and decreases in cross-section.
* Reections from changes in soil layers.
* Reections from signicant changes in material properties (e.g.
variation in concrete consistency).
PHenoMenA not DetectABLe
* Gradual increases or decreases in cross-section.
* Curved forms.
* Small inclusions of foreign materials.
* Local loss of cover.
* Debris at the toe of the pile.
* Cracks parallel to the pile axis.
SONIC INTEGRITY TESTING
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L l 1 4 B b k Pl
SONIC INTEGRITY TESTING, cont
Sonic integrity teSting
HoW DoeS it WorK?
1. The pile head is struck with a hand-held hammer, which sends a
low strain stress wave down the pile shaft.
2. The induced stress wave is reected off the pile toe and any
discontinuities in the pile.
3. The reections cause movements of the pile head, which are
registered by a hand-held accelerometer sensor that is pressed
against the top of the pile.
4. The recorded signal is converted into a velocity-time trace and
presented on-screen as velocity versus pile depth.
5. Once satisfactory signals have been obtained, they are stored in
the internal memory of the eld computer.
6. The stored signals are downloaded onto a PC for signal
enhancement and reporting at a later stage.
The shape of the recorded sonic signals (reectograms) provides aqualitative indication of the pile integrity. However, interpretation of
SIT signals must give due regard to the soil prole in which the pile
is founded and the method of pile construction. Shaft friction plays a
major role in damping the signal and reections of stress waves also
occur at the boundary of soil layers. For this reason it is essential that
the operator is provided with available soil prole details, together withthe pile construction records.
Recommended