Note: Descriptions are shown in the official language in which they were submitted.
13~9~7
PILE DRIVING APPARATUS
This is a division of Application Serial No. 596,736
filed April 14, 1989 for "Pile Driving Apparatus".
This invention relates tc pile driving apparatus, in
particular to jack piling systems.
Jack piling apparatuses are usually confined to
situations where piles must be driven into the ground and no
significant vibration and noise is permitted. Several pile
driving apparatuses have been proposed in the past. Several
are discussed in "Pile Design and Construction Practice", third
edition by M. J. Tomlinson, published in 1987.
Previously used jack piling apparatuses employ the
use of a jack which bears down directly onto the top of the
pile to be driven into the ground. These systems are
frequently referred to as "jack-in piling systems". These
systems are mainly used for underpinning foundations, but
owing to their relative complexity, are not competitive with
conventional piling systems and so are seldom used in new pile
foundation works
One previously used jack piling apparatus involves
inserting a jack between the foundations to be
-.,. 133g457
underpinned and the top of the pile to be driven into
the ground. In this kind of system, the foundations
themselves provide the reaction force to the jacking.
These systems are subject to m~ny disadvantages. In
particular, the set up and positioning of the pile, and
mobilization of the Kentledge or ballast to provide the
reaction is slow. Generally, a hydraulic jack is used,
but are restricted to shorter strokes. This means that
extensive use of dolly sections is required, at least
six times to jack down one section of the pile.
Moreover short and stout pile sections must be used,
which means that the apparatus is only really suitable
for larger bearing capacity piles (such as 40 tonnes
above working load).
The~Q sy8t.Qm8 arQ alho di~a~vantageous in that the
~t~n~i~n pllë pr~ ure is slow, and the joining of
consecutive piles together, frequently done by welding,
is inefficient.
Such jack-in piling systems can only install two pile
positions per working day. This makes such jack-in
piling systems uneconomical for extensive use even in
the present pile foundation market.
- 13394S7
It ls an aim of the present lnvention to provlde a plle
drlvlng apparatus which overcomes the aforementloned
dlsadvantages.
- According to the present invention, there ls provlded a
plle drlvlng apparatus comprlslng:
~ack.means positioned at least partlally alongslde a plle to
be drlven for exertlng a plle drlvlng force in a dlrectlon
substantlally parallel to but spaced apart from the longltudlnal
axls of the plle to be drlven, at least a part of sald ~ack means
extendlng alongslde the plle;
transmlsslon means for tran~mlttlng the plle drlvlng force
from sald ~ack means onto the plle;
reactlon means for provldlng a reactlon force to the plle
drlvlng force;
a column means for recelvlng the plle to be drlven, sald
column means havlng an upper end and a lower end; and
a base frame attached to sald lower end of sald column means,
sald base frame lncludlng ballast support means for supportlng
ballast, sald ~ack means belng posltloned on sald column means.
The column means preferably comprlses a column for
recelvlng the plle along lts length on one side thereof, the
length of the plle substantially correspondlng to the length of
the column.
The ~ack means may be flxed to one end of the column on
the slde of the. column whlch ls opposlte from the slde recelvlng
the pile.
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The transmission means may comprise a first thrust
member for receiving a piston of the jack means, a
second thrust member ~or urging against the free end of
the pile, and a transmission member which links the
first and second th.-ust members via an aperture
extending along the length of the column.
The piston of the ~ack means is preferably capable of
pushing the first thrust member along substantially half
of the length of the column in a single stroke, thereby
permitting driving of the pile in tWO stro~es of the
jack means.
A base frame is attached towards the lower end of the
column, and comprises support means for supporting the
apparatus, and levelling means for levelling the base
and ensuring the column is at leas~ substantially
vertical.
The base frame is preferably arranged to support ballast
or Kentledge for providing the reaction force to the
pile driving force, the reaction force being transmitted
between the ballast or Kentledge and the jack means via
the column.
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The column may be ln the form of a steel "H" cross-
sectional column.
According to the present lnventlon, there is further
provided a base frame for a ~ack pillng apparatus, the base
frame comprlsing support means for supportlng a plle to be
driven lnto the ground, and supportlng a ~ack means for
drlving the plle lnto the ground, and for supportlng ballast
or Kentledge for provldlng a reaction force to the iack means,
wherein the base frame includes levelling ~acks operative to
ad~ust the base frame so that the pile can be made to be
substantlally vertlcal.
The base frame ls constructed so as to be
sufflciently stlff to resist dlstortions due to the reactlon
force whlch occurs durlng plle drlving.
Accordlng to the present lnventlon, there is
provlded a plle loadlng devlce for loadlng plles lnto a plle
drlvlng apparatus, the plle loadlng devlce comprlslng an
elongate cradle whlch ls plvotally connectable to the
apparatus so that the cradle can be moved between horlzontal
and vertlcal posltlons, and a ~ack for movlng the cradle about
the plvotal polnt, whereln the cradle ls conflgured to recelve
a plle when ln the horlzontal posltlon, and to be moved lnto a
vertlcal posltlon by
. ~ ~
1339~57
means of the jack thereby enabling positioning of the
pile for driving into the ground.
The loading device is preferably provided with means for
guiding the end of the pile closest to the pivotal end
of the cradle for locating it with the exposed end of
the previously driven pile.
The pile loading device is also configured for placing a
dolly onto a partially driven pile.
The guiding means may be adjustable to accommodate
different pile profiles.
The pile loading device and/or base frame may be
incorporated in~o the pile driving apparatus as defined
hereinbefore.
Embodiments of the invention may include a jointing
apparatus for connecting adjacent piles end to end, and
for restraining relative movement between the piles in
the 3 degrees of rotational motion, and the 3 degrees of
translational motion.
According to the present invention, there is provided a
jointing apparatus preferably comprises a plate having a
13~9~
cross-section corresponding substantially to that of the
pile to be driven, bonding means extending from one side
of the plate around which the pile is cast thereby
enabling bonding of the plate to the pile, and a channel
f~rmed in the plane of the plate and for receiving a leg
of a substantially '~Cl~ or ~U~ shaped clip such that
there can be no relative movement between the clip and
the plate.
The other leg of the clip can be received by a
corresponding ressess of a corresponding plate cast into
another pile. Positioning of the plate clip in this way
joins the piles and prevents relative movement
therebetween.
A plurality of channels may be formed in end plate for
receiving a corresponding number of clips thereby
providing extra security againsc relative movement
between adjacent piles.
The pile driving apparatus of the present invention,
~hich may include the base frame and/or the pile loading
device, may be suspended from or attached to a mobile
crane.
- 1~394~7
- 8 - 73074-3
Instead of mounting the apparatus on a base frame,
the apparatus may be mounted onto a mobile base machine which
has sufficient weight to provide the reaction force.
~ mbodiments of the present invention provide signi-
ficant advantages over previously used jack-in pile driving
systems.
A significant advantage is afforded by the pile
driving apparatus of the present invention owing to the in-
direct application of the driving force from the jack means to
lo the pile.
The advantages are as follows: a smaller but longer
pile element having a pilo bearing capacity ranging froln 10
to 40 tonnes (working load) can be driven; the ballast or
Kentledge can be simply and quickly mobilized; the pile exten-
sion procedure can be carried out quickly without much manual
labour; piles may be joined together simply and inexpensively;
the hydraulic jack can install the section of pile by only
two stokes thereby reducing the number of dolly usages (this
leads to a speeding up of the overall pile driving process);
and since at least a part of the jack means is arranged to
extend alongside the pile, the length of the pile element
can correspond
- 1339457 "''
to the available headroom, which in turn leads to a
greater stability during driving of the pile.
Embodiments of the present invention thereby enable
longer jacking strokes and a faster piling extension
pcocedure. Embodiments of the invention can install
about 20 pile positions in a working day.
Embodiments of the present invention are therefore cost
competitive with other existing pile systems which are
not generally designed for underpinning works.
Moreover, embodiments of the present invention do not
preclude the use of twin or multiple hydraulic jack
assemblies for providinq the pile driving force.
Embodiments of the present invention may be used for
pre-stressed concrete pile elements of various
cross-sectional shapes, for example, triangular, I'V't
shaped s~uare, round, hexagonal or tubular.
Pre-stressed concrete pile elements are preferably
pre-tensioned using a single pre-
stressing wire along the central longitudinal axis of
the pile. Several pre-stressing wires can also be
used. Piles of 125 mm to 225 mm in lateral dimension
may be used.
1339~7
Embodiments of the invention enable use of pre-stressed
concrete pile elements having effective pre-stress of
less than 2 MPa. Piles made of other materials such as
timber or steel may also be driven into the ground using
embodiments of the present invention, Lengths of pile
elements may, for example be between 3 and 6 metres long.
The invention will now be ~urther described by way of
example with reference to the accompanying drawings, in
which:
Figure 1 is a sectional plan view taken along the lines
A-A (of Figure 2) of an embodiment of the present
invention;
Figure 2 is a sectional side elevation taken along the
lines B-B of Figure l;
Figure 3 is a detailed sectional plan view of part of
the embodiment of the present invention;
Figure 4 is a part sectional side elevational view of
the embodiment taken along the lines B-B of Figure 3;
Figure S is a schematic view of an embodiment of the
invention supported by a mobile base machine;
Figure 6 illustrates an embodiment of the invention
mounted on a static base frame which is positioned using
a mobile crane; and Figures 7a and 7b respectively show
133g4~7
plan and side elevational views of a clip for clipping adjacent
piles together; and
Figures 1 and 2 illustrate an embodiment of the
invention which comprises a base frame 1 having a platform 3 for
supporting ballast or Kentledge 5. The base frame 1 is prefer-
ably constructed of steel sections or steel plates which are
sufficiently stiff to prevent any significant distortions
occurring when the reaction force is applied during pile instal-
lation.
The base frame 1 is equipped with a levelling device
in the form of jacks 7 positioned at each corner thereof. Each
jack 7 can be adjusted independently of one another so as to
ensure that the base frame lies substantially horizontally, and
in particular, to ensure that a pile 8 (see Figure 3) to be
driven into the ground is vertical with respect to the ground.
The Kentledge or ballast may be weights totalling 40
tonnes. One 10 tonne weight 9 may be positioned at each corner
of the base frame 1 above a jack 7.
The pile driving apparatus comprises a column 11
positioned substantially perpendicular with respect to the base
frame 1, and supported in position by means of
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12
steel supports 13. Bracing members 15 are proYided on
the base frame 1 in order to enhance the stiffness of
t he appara tUS .
The column 11 will be described in detail below with
reference to Figures 3 and 4. At the top of the column
11 is pro~ided a lifting point 17 which can be attached
to the hook of, for example, a mobile crane thereby
enabling positioning of the apparatus.
The apparatus includes a pile loading device which
consists of a cradle arm 19 which is pivotally mounted
at point 21 to the base frame 1, at the lower end of the
column 11. A hydraulic iack 23 is positioned on the
base frame 1 and comprises a hydraulic piston 25 which
is connected to the cradle arm 19. The operation of the
cradle arm will be discussed below.
Figures 3 and 4 illustrate the column 11 of the pile
driYing apparatus in more detail. The column 11 is
constructed of a steel "H~ profiled column which is of
sufficient strength to transmit the reaction force from
a jack means to the Kentledge. The jack means is in the
form of a hydraulic cylinder 27 and a hydraulic piston
29. The hydraulic cylinder 27 is fixedly attached ~o
the top end of one side of the column 11. This side of
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13
the column 11 forms a hydraulic jack compartment of the
pile driving apparatus.
The other side of the column 11 forms the pile
compartment 31 of the pile driving apparatus. The pile
compartment 31 receives the pile 8 for driving into the
ground.
A transmission means transmits the pile driving force
from the hydraulic cylinder 27 to the pile 8 contained
in the pile compartment 31. The transmission means
comprises a jack thrust plate 33 onto which the driving
load of the hydraulic piston 29 bears. The jack thrust
plate 33 is rigidly connected to a transmission plate 35
by means of a shear plate 3? which is welded onto the
transmission plate. The higher end of the transmission
plate 35 is rigidly connected to a pile thrust plate 39
by means of another shear plate 41. The web portion 43
of the column 11 is provided with an elongate slit
running along the longitudinal length thereof for
accommodating ~he transmission plate 35 and for
permitting the transmission plate to move along the
length of the column 11. As can be seen from Figure 4,
when the hydraulic piston 29 urges downwardly against
the jack thrust plate 33 in the direction of arrow A, a
corresponding downward thrust is transmitted via the
133~457
transmission plate 35 to the pile thrust plate 39.
The configuration of transmission means is such that the
hydraulic cylinder 27 and the hydraulic piston 29 can
extend alongside the pile to be driven into the ground.
Consequently. piles having a length substantially
corresponding to the height of the column 11 may be
driven into the ground with embodiments of the present
invention.
In order to enhance the stiffness of the column 11,
stiffener plates 45 are welded along the length of the
web portion 43 of the column 11. In the hydraulic iack
compartment of the column 11, there is provided a
channel section g7 which acts as a guide for the
transmission plate 35. The channel section 47 also
reduces the possibility of the transmission means
twisting within the slit formed in the web portion 43.
The pile thrust plate 39 has a cross-section which
corresponds to the cross-section of the pile 8. This
thrust plate 3~ makes contact with the pile to be driven
into the ground.
The hydraulic piston 29 is capable of extending to
substantially half the length of the pile 8, thereby
13~94-~7
driving half the length of the pile into the ground in
one stroke,
This embodiment is provided with the pile loading device
which comprises the cradle arm lg which is pivotally
mounted at the point 21 to the base frame 1 at the lower
end of the column 11. The operation of the pile loading
device is as follows.
The cradle arm 19 is lowered, by means of the hydraulic
jack 23 and piston 25, into a horizontal position as
illustrated in Figure 2. The pile element 8 is then
lifted and placed horizontally onto the cradle arm 19
either manually or by crane. The hydraulic jack piston
25 then retracts causing the cradle arm 19 to swing into
a vertical position together with the pile element to be
loaded into the pile compartment 31 of the column 11. A
guide 49 is proYided on the cradle arm 19 which ensures
that the lowermost end of the pile element is correctly
located above the correct position on the ground, or if
the pile element is an extension pile, the adapter 49
ensures that the lowermost end of the pile extension
accurately locates with the top of the pile element
already driven into the ground.
16 ~339457
The guide 49 may be adjusted to accommodate eiles of
different profiles and sizes.
Figure 5 illustrates the pile driving apparatus of the
present embodiment mounted on a mobile base machinc 50,
The pile driving apparatus may be transported by the
mobile base machine 50 as illustrated in Figure 5. The
column 11 is supported on the mobile base machine 50 by
means of a steel hollow section column 51 which is
pivotally supported at a point 53 of the mobile base
machine 50. The pile driving apearatus can be deeloyed
by means of the hydraulic arm 55. During deployment,
the mobile base machine 50 can be stabilized by means of
a stability jack 57.
Figure 6 illustrates the pile driving apparatus mounted
on a static base frame which is positioned using a
mobile crane 52. The mobile crane also loads the
Kentledge onto the base frame The column 11 is
suspended from the mobile crane 52 by means of a hook
attached to the lifting point 17 of the column 11. The
horizontal positioning of the base frame 1 can be
controlled by means of a position control attachment 59
which can be controlled by the mobile crane 52.
1339457
17
The installation of piles by the embodiment of the
invention will be described as follows.
The mobile base machine or crane may be capable of
liftinq a 10 tonne load. The bearing capacity of the
pile may be 16 tonnes working load, and the pile length
per element may be 5 metres. During installation, the
column 11 and base frame 1 are first lifted into place
and positioned over the desired location. The four 10
tonne Kentledge pieces are then lifted and placed into
position on the base frame 1 to form the ~entledge.
Levelling of the base frame 1 can then take place in
order to ensure that the column 11 is vertical.
While this is being done, the cradle arm 19 is lowered
to the horizontal position in order Co receive the pile
element. The hydraulic jack 23 and 25 then lifts the
cradle arm 19 and pile element into the pile compartment
31, and the pile thrust plate 39 is located on the top
end of the pile.
The hydraulic cylinder and piston 27 and 29 can then
drive the pile element, via the indirect jacking force
method of the invention until, for example, half of the
pile element is driven into the ground. The hydraulic
eiston 29 can then be retracted to its original position
13~94~
18
when the loading of the pile took place. During
retraction of the piston 29, the cradle arm 19 is again
lowered to the horizontal position in oraer to receive a
steel dolly. The cradle arm 19 then lifts the dolly
(not shown) into the pile compartment -1 with the dolly
end resting flat on the half embedded pile element.
.
The hydraulic piston 29 is then activated again and the
dolly pushes the remaining half o~ the pile element
downwards. The cradle arm 19 can then be used to remove
the dolly and further extension pile elements can then
be driven into the ground using the above procedure.
Once the required pile penecration or bearinq capacity
has been reached, any pile elements protruding from t~e
ground can be cut by means of an appropriate special
cutter. The Kentledge can then be unloaded from the
base frame and the apparatus then lifced to another pile
position for repeat procedures.
Adjacent ends o~ extension piles may be connected
together by means of the "clip in" jointing system of
the present invention. An example of such a jointing
system will be described below.
lg 13~9457
Figures 7a and 7b illustrate an embodiment of clip-in
jointing system according to the present invention. The
jointing assembly comprises a substantially ~V~-shaped
or triangular shaped plate 61 having the same
cross-section as ~he pile element to be driven into the
ground. A recess 63 is formed on each of the three
sides of the plate 61 for receiving a linking portion 65
of a substantially "U" or "C" shaped clip 67. A plate
69 is welded to the plate 61 at each of the recess
points 63, and provides a channel 71 or hole for
receiving a leg 73 of the clip 67. A bonding bar 75 is
welded to each of the plates 69.
The end of the concrete pile is cast around the bonding
bars 75 thereby securely bonding the plate 61 to the
pile element.
Tensile stress resultants are transferred from the
concrete pile element to the bonding bars 75 by
interface bond. These stresses are in turn transferred
through the channel shaped plate 69 and the V-shaped or
triangular shaped plate 61 which have been welded to the
bonding bars 75. Through contact stresses, the tensile
stress resultants are transferred via the clip 67 to the
adjacent pile end of similar construction.
13 3 9 ~ ~7
For com~ressive stress resultants, these stresses are
transferred through direct contact stresses becween the
V-shaped plate 61 of adiacent pile elements.
During installation of pile elements, as soon as the two
pile elements have been positioned end to end, the two
legs 73 of the clip 67 can be simply and easily inserted
into the channels 71.
The clip 67 is slightly profiled during manufacture to
provide a slight interference or press fit during
insertion at the joint.
Three or more clips 67 are positioned in order to
rigidly secure the pile end together thereby restraining
relative movement therebetween in each of the 6 degrees
of freedom (ie 3 rotations and 3 translations).
The advantages afforded by embodiments of the present
invention can be contrasted with established jack-in
pile systems as follows.
Existing jack-in pile systems are restricted to
relatively short pile elements, typically of 0.76 to 1,2
metres in length owing to the ability of the pile
element to be manoeuvred by human strength. This leads
l~g4~7
21
to a large number of joints being re~uired to instal a
pile. Embodiments of the invention enable the use of
.elatively long pile elements, typically 3 to 6 metres
in length since ~he pile can be manipulated by the
machiner~ instead of relying on human effort. Also,
fewer joints are re~uired.
Also in embodiments of the invention, moderate side
dimensions of piles may be employed, for example, 100 mm
to 200 mm, whereas in established systems 300 mm
erecast concrete piles are used.
In existing systems, the existing foundation is often
used to provide the reaction for the jacking forces.
However, embodiments of the invention enable Kentledge
to be placed on a mobile machine or on the base frame of
the apparatus itself. The Kentledge can easily be moved
to a new position where re~uired, and is not restricted
to the position of the existing foundations.
Embodiments of the invention are also advantageous in
that they permit a long stroke of the jack, for example,
1.5 ~o 4 mecres thereby enabling an entire pile elemenC
to be installed in two strokes. In contrast,
conventional systems have a short jack stroke of, for
example, 0.25 metres thereby re~uiring a multiple number
22 1339457
of strokes required to install a single pile element.
Embodiments of the invention may incorporate the clip-in
jointing system described hereinabove which enables the
ioints of adiacent piles to be established speedily.
This contrasts with prior art arrangements wherein
precast concrete elements are bonded together by
inserting short steel bars into the longitudinal central
hole, and subsequently grouting them with cement.
.
Embodiments of the present invention enable full use of
the available headroom, the headroom corresponding
substantially to the length of each pile element to be
used. For example, a 3 metre length of pile elemenc may
be installed in the headroom of only 3.1 metres. This
contrasts with the prior art in which working headroom
is required to accommodate both the length of the pile
element and the hydraulic jack plus any packing. For
example, a working headroom of about 1.8 metres enables
installation of only a 1.2 metre length of open-ended
steel tube.
Another difficulty with prior art arrangements is that
the hydraulic jack and packing must be removed before
another pile element can be added to the previous
element already jacked into the ground. The jack is
133g4,~7 '
- 23 -
then put into position. In contrast, in embodiments of the
invention the hydraulic jack 27 and 29, remains in position until
the entire pile is installed to a required depth or bearing cap-
acity.
Prior art arrangements are restricted for use in under-
pinning existing foundations. However, embodiments of the
invcntion makc it compctitivc to bc uscd for ncw building found-
ations. Embodiments of the invention are not only cheaper and
faster when used for underpinning existing foundations, but they
will find substantial use for new foundations and are not re-
stricted to underpinning existing foundations.
Embodiments of the invention also enable the use of twin
or multiple hydraulic jacks to be used for providing the jacking
force.
