Pile foundations - Duktus

Ductile iron pipe systems for
Pile foundations
Quick, easy and safe!
Driven piles of ductile cast iron
Axial compression forces up to 1400 kN •
Piles are full-displacement •
Piles of a desired length up to 50 metres •

Driven piles of ductile cast iron
Safe and highly versatile foundation components
The building industry needs simple and safe pre-formed driven pile systems
which are suitable for a wide range of applications. The driven cast iron pile
is driven into the ground to a desired length and transmits forces from the
structure situated above it into the ground. The ductile pile is an economical
and technically acceptable alternative to conventional methods of laying
deep foundations. Carrying working loads of up to 1400 kN, the ductile pile
is suitable for foundation work of almost any kind.
Being economical while giving high productivity on sites which are simple
to set up, this system is not only suitable for large-scale projects but can
also be used at low cost on small to medium-sized building projects.
The load is transmitted either by end-bearing pressure in the case of ungrouted
end-bearing piles or by skin friction in the case of pressure-grouted
piles.
Austria – Factory enlargement in the centre of Salzburg – Pressure-grouted driven piles of ductile cast iron up to 59 m in length transmit loads of 800 kN
The advantages
• Sites are simple to set up because the equipment used is relatively light
and easy to manoeuvre.
• Corrosion resistance is high compared with structural steel.
• Pile lengths can be adjusted reliably to changing soil conditions. The
shaft bearing capacity can be checked while piles are being driven.
• Individual pile pipes are quickly connected by frictional connections on
the site itself and no special tools or welding are needed.
• Installation with almost no transmitted vibration. Piles can be installed on
gap sites. Minimum spacing of pile centreline from existing buildings is
40 cm.
• Extremely economical. Capital costs are low and productivity is high at
200-400 running metres a day.
• No spoil from boring, no off-cuts and no re-machining of the heads of
piles.

Highly versatile, with the
environment in mind
Buildings
Foundations for buildings on gap sites: the
manoeuvrable equipment and short completion
times are a big advantage on inner-city sites.
The use of pile caps of the same width as the
walls means considerable savings on foundation
concrete.
Industrial buildings
Foundations for prefabricated buildings: loads
can be carried safely by piles grouped to support
small pocket foundations. Highly suitable
for lightweight structures with their sensitivity to
settlement and especially to differential settlement.
Wind loads and loads from the supporting
structure are transmitted safely into the ground.
Bridge-building
Foundations for bridge abutments: sites are
quick and easy to change over for pile driving.
Moments are transmitted by pile bents and
horizontal forces by raking piles.
Pile-supported pipelines
Foundations for pipelines: can be used in sewer
and water pipeline laying to prevent unacceptable
settlement in soils of low bearing capacity.
Software-assisted sizing of pile-supported pipe
systems.
Slope stabilisation
Stabilisation against slippage of slopes, embankments,
ground prepared for ski runs, and so
on. To provide stability, piles can be installed in
vertical to near-horizontal positions to accompany
construction work or as an urgent remedial
measure.
Silo foundations
Foundations for silos, tower cranes, power
line pylons and radio masts: foundations are
stressed in compression and tension. Structures
of considerable height subject to cyclic wind
loads are founded on pile bents with additional
tensile reinforcement.
Trench shoring
To create a retaining wall in the area of an adjacent
existing building. The piles are held in the
soil of good bearing capacity at a point below
the floor of the trench and at the head end they
are connected to an anchored belt of reinforced
concrete.
Uplift control
Foundations for sedimentation tanks, road
underpasses and construction trenches at
depths within the range of variation of the water
table. The concrete floor is safeguarded against
floating up by additional tensile reinforcement set
into the concrete.
Strengthening of foundations
Strengthening and underpinning of existing
structures: inside industrial and other buildings
where the working height is limited, old foundations
are strengthened or new foundations are
laid retrospectively to carry additional loads or
for underpinning.
Spain – Lebrija solar energy park. 14 hectares, 3.2 MW
Austria – Poysdorf-Wilfersdorf wind park. 14 Vestus V90 wind turbines, 28 MW
Austria – Grimming-Therme low energy building. 500 geothermal heat probes, 22,000 m 2
Italy – Noise barriers for the Brenner railway line, barriers along a 4.5 km stretch of the line
Austria – Flood protection for the Leutascher Ache river, environmental upgrading of a
section of the river

An approved pile system
5.0 metre long pile pipes
The ductile cast iron pile pipes, with a tapering spigot end and a tapering
socket, are assembled into a continuous pile of a desired length.
• Efficiently transportable and site logistics are simplified
• Easy to handle
• Pile lengths can be up to 50 metres
The lengthening of the pile is performed quickly, safely and securely by means of a frictional tapered socket joint
A full range of products
The pile system includes all the accessories to form the heads and toes of
piles, and anvils to suit any hydraulic hammer.
• Pile-supported pipelines: Pile-pipe saddles for DN 200 to DN 500
pipelines
• Drive shoes and drive tips for grouted and ungrouted piles
• Coupling sleeves for connecting shortened piles when headroom is
limited
European technical approval and CE marking
Pile accessories to suit the nature of the load transmission and the
foundation ground and supported structure
Frictional socket joint
The driving process and the high impact energy produce a rigid joint stiff in
bending between the pile pipes.
• The individual pipes can be connected quickly on the site itself
• No special tools or welding work needed
• Flexible adjustment to the foundation ground: assurance of correct
lengthening of the pile shaft
Typ
Wall thickness
mm
Mass
kg/m
Moment of
inertia cm 4
Grouting and non-grouting anvils available for many different types of hammer
Resisting
moment cm 3
118 7.5 21.0 399 68
118 9.0 24.4 461 78
118 10.6 28.0 521 88
170 9.0 37.2 1,480 174
170 10.6 42.6 1,693 199

Economical to use
Driving equipment used is compact
Even when the space available is confined, the low weight of the pile pipes
to be driven means that they can be driven with a light and manoeuvrable
hydraulic digger using a hydraulic double-acting hammer.
• Sites are quick and easy to set up and change over
• Low capital investment costs
• Space required is small and driving platform requirements are modest
Checking of shaft bearing capacity during driving
Ungrouted and grouted piles
Depending on the nature of the soil, ductile piles can be driven either
ungrouted (end-bearing piles filled with concrete) or grouted (friction piles,
sheathed and filled with mortar).
An incision for concrete to escape through is made in the first pipe
Piles are full-displacement
Each pile pipe is inserted in the tapered socket of the pipe driven previously
and the pipe string is driven into the foundation ground to the final depth
by displacing the soil. The projecting end is cut off precisely to the planned
height.
• No drilling spoil is produced hence no disposal costs
• No re-machining of the pile heads
• No waste: the length cut off is re-used as an initial pile pipe
• No driving for redundant lengths: driving takes place in the already
completed prior excavation
• No change in the groundwater balance
Grouting takes place simultaneously with the installation of the pile
Simultaneous pressure grouting
A widened driving shoe creates a cavity around the entire circumference of
a pile pipe as it is driven. As the driving progresses, a pump continuously
grouts this cavity with mortar.
• Short installation times
• High productivity of 200 to 400 m a day
• Pile lengths are optimised by the compacting of the soil and the
interengagement with it
• No re-grouting required
The projecting end is cut to the planned height and re-used as a starting section for the next pile

Proven over more than 3 million metres
Check on base bearing capacity
The pile pipes are available in two diameters, 118 mm and 170 mm, and
in wall thicknesses from 7.5 mm to 10.6 mm. They are generally filled or
grouted with concrete of strength class C20/25 or C25/30.
• Sized to Austrian Technical Regulation ONR 22567
• Corrosion rate does not have to be considered for mortar-sheathed
grouted piles
• Safety factor of 1.5 for the cast iron material
Safety on the site
The soil is displaced sideways and therefore no need for drilling spoil to be
flushed out with high-pressure water or air. The manual work is confined to
minor physical exertions which are not dangerous.
• Less risk of accidents
Type
Wall
thickness
mm
Pile
Bearing capacity in kN
Pile + concrete
(C20/25)
Pile + concrete
(C25/30)
118 7.5 521 660 678
118 9.0 616 747 764
118 10.6 715 837 854
170 9.0 910 1,212 1,253
170 10.6 1.062 1,352 1,391
Table 1: Maximum permitted base bearing capacity (kN) for pressure grouted piles, and for
non-pressure-grouted piles up to corrosiveness level AS1 under Austrian standard B 5013-1
(no corrosion rate).
Type
Wall
thickness
mm
Pile
Bearing capacity in kN
Pile + concrete
(C20/25)
Pile + concrete
(C25/30)
118 7.5 465 604 622
118 9.0 561 692 709
118 10.6 660 782 799
170 9.0 831 1,133 1,174
170 10.6 982 1,272 1,311
Table 2: Maximum permitted base bearing capacity (kN) for non-pressure-grouted piles – corrosiveness
level AS2 under Austrian standard B 5013-1 (corrosion rate of 1.5 mm at diameter for 100 years).
Type
Wall
thickness
mm
Pile
Bearing capacity in kN
Pile + concrete
(C20/25)
Pile + concrete
(C25/30)
118 7.5 375 514 532
118 9.0 471 602 619
118 10.6 570 692 709
170 9.0 699 1,001 1,042
170 10.6 851 1,141 1,180
Table 3: Maximum permitted base bearing capacity (kN) for non-pressure-grouted piles – corrosiveness
level AS3 under Austrian standard B 5013-1 (corrosion rate of 4.0 mm at diameter for 100 years).
Check on shaft bearing capacity
Ductile piles are driven to the final depth, which is established from penetration
resistance. The penetration resistance which is measured is used as a
criterion for stopping the driving and for the bearing capacity of the ground
strata which are entered.
• Pile length can be matched to the soil conditions actually encountered
• Shaft bearing capacity can be checked during driving
• Skin friction values of up to 150 kN/m 2
• Correlation exists between driving times and permitted skin friction values
Driving with little vibration
Measurements made on sensitive sites have repeatedly shown that the
installation process is an environmentally gentle one. The vibration levels
measured were always only a fraction of the permitted levels.
• Piles can be driven with centrelines down to 40 cm from existing
structures
Driving times
s/m
Compactness
of ground
DPH
(N10)
SPT
(N30)
Skin friction
values kN/m 2
Pressed Very loose 0-2 30 Very dense >30 >50 150
Table 4: Correlation between driving time, number of impacts in driving tests and associated skin
friction values for non-cohesive soils (safety factor of 2.0 included).
Driving times
s/m
Stiffness of
ground
DPH
(N10)
SPT
(N30)
Skin friction
values kN/m 2
Pressed Mushy – – 0
Pressed Soft 0-1 0-2 0
5-10 Soft to stiff 2-5 3-8 (20)
10-15 Stiff 5-7 8-15 (40)
15-30 Semi-firm 8-15 16-30 70
>30 Firm >15 >30 100
Table 5: Correlation between driving time, number of impacts in driving tests and associated skin
friction values for cohesive soils (safety factor of 2.0 included).

Made of a modern material
Corrosion resistance
The high carbon and silicon contents and the annealing skin produced by
the production process give ductile cast iron (spheroidal graphite cast iron)
greater corrosion resistance as compared with structural steel.
High impact resistance
The addition of magnesium to the molten iron shortly before it is centrifugally
cast and the post-annealing process which follows endow the cast
iron with its ductility and strength.
• Can be driven with powerful hydraulic hammers
• No risk of over-stressing during the driving
Pipes are produced from recycled iron and are themselves fully recyclable
Industrial pre-forming
As an accompaniment to production, continuous checks are made on
quality to the relevant standards. The quality assurance process covers the
chemical composition, the mechanical properties and the dimensions.
• Quality monitored to EN standards, ISO 9001 certification
• Large stock: even short delivery times are possible
The formation of spheroidal graphite confers high corrosion resistance and impact resistance
Material is 100% recycled
The metal charge for the smelting of the basic iron consists entirely of raw
materials from the recycling industry, laminated transformer and other
cores, carefully sorted steel scrap and other recycled material.
Pile production from molten iron by the centrifugal casting process
EN-GJS-400-10 spheroidal graphite cast iron
Compression strength 900 MPa
Tensile strength 420 MPa
0.2% offset yield stress 300 MPa
Modulus of elasticity 170,000 MPa
Density 7,050 kg/m3 Accompanying monitoring of the quality of each individual pipe

Duktus S.A.
GERMANY
Manfred Schmied
M +49 (0) 171 30 58 547
manfred.schmied@duktus.com
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6060 Hall in Tirol
Austria
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www.duktus.com
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M +43 (0) 664 85 64 195
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