Note: Descriptions are shown in the official language in which they were submitted.
ABSTRACT
The invention relates to a foundation for a wind turbine, wherein the
foundation (10)
comprises substantially prefabricated elements, preferably of reinforced
concrete, with a
first, vertically extending base-like section (11), on which a tower of the
wind turbine can be
arranged, with a second, substantially horizontally extending section (12) as
foundation
body, which is in contact with the ground (100) and comprises at least two
horizontal
elements (22) with at least one support section (25) at its inner end, wherein
the first section
(11) is arranged above the least two support sections (25), which is in
contact with the
ground (100), which has at least two horizontal elements (22) with at least
one support
section (25) at its inner end, the first section (11) being arranged above the
least two support
sections (25) of the second section (12), and with a third section (12a) which
is arranged
below the least two support sections (25) of the second section (12). It is
provided according
to the invention that a base (20) is provided which is formed at least from
the first vertically
extending base-like section (11), from the at least two support sections (25)
of the second
section (12) and from the third vertically extending base-like section (12a),
that the three
sections (11, 12, 12a) thereby form at least three layers (13, 16, 17)
arranged one above
the other, of which the upper and lower layers (13, 17) are formed from at
least two layers
(13a, 13b, 17a, 17b) of ring-like design and the middle layer (16) is formed
from at least one
layer (16a) of ring-like design, in that the height (H+1, 2x J) of the upper
and/or lower layer
(13, 17) is smaller than the height (K) of the middle layer (16), and in that
the layers (13, 16,
17) are vertically braced to the second section (12) by means of at least two
vertical tendons
(19).
*****
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Description
Foundation for a wind turbine
The invention relates to a foundation for a wind turbine, the foundation
comprising
substantially prefabricated elements, preferably of reinforced concrete, with
a first, vertically
extending base-like section on which a tower of the wind turbine can be
arranged, with a
second, substantially horizontally extending section as a foundation body,
which is in
contact with the ground, which has at least two horizontal elements with at
least one support
section at its inner end, the first section being arranged above the least two
support sections
of the second section, and with a third section which is arranged below the
least two support
sections of the second section.
Foundations for wind turbines are essentially constructed as in-situ concrete
foundations.
For this purpose, a pit is excavated at the erection site, which is then
provided with a clean
layer. The formwork and reinforcement are then erected and the whole is filled
with concrete
on site. In this process, a flat body is erected, if necessary, with a base,
see for example
US 20160369520 Al or WO 2008/036934 A2. Besides the transport effort due to
the
delivery of the concrete, formwork and reinforcement, this is very labor-
intensive on site.
Quality assurance is also costly or, depending on the weather, problematic.
Furthermore,
the dismantling after the end of the service life of the wind turbine is
expensive and very
time-consuming. This applies in particular to concrete towers for wind
turbines, which ideally
have a diameter to height ratio of approx. 1:10, so that diameters of 8 to 15
m are not
uncommon. Foundations for such towers have so far been made in cast-in-place
concrete.
Furthermore, areas must be provided where the prestressing elements of the
tower can be
attached to the foundation and prestressed. The prestressing is carried out
with devices
provided for this purpose, which have to be brought into the prestressing
areas. As
abutments for prestressing or for attaching the prestressing elements
(strands/cables),
elaborate cantilever structures are usually provided inside the foundation,
under which the
devices are then brought. These structures are costly and in need of
improvement.
Furthermore, there is in principle a need to construct wind turbine
foundations from
prefabricated elements, which would reduce or eliminate the aforementioned
problems. In
principle, the advantage of prefabrication is that the components can be
produced in a
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standardized manner under defined conditions. It also reduces the amount of
work required
on site. Various approaches to this have been described in the state of the
art.
For example, WO 2008/036934 A2 shows a combination of precast elements and
classic
formwork/reinforcement construction. This reduces the previously mentioned
disadvantages only insignificantly.
Other approaches for making foundations for wind turbines from prefabricated
components
are shown in the prior art as follows:
EP 1 058 787 B1 discloses a foundation for a wind turbine for erecting
offshore wind turbines
that are transported completely pre-assembled - i.e., including the foundation
- and set
down in one piece on the seabed at the erection site. The foundation has
individual
prefabricated segments. These can be made of concrete. A planar section and a
base
section are disclosed. The base section consists of circular rings. The planar
section
consists of individual base elements that are trapezoidal in base area, on
which the base
section is vertically mounted at the inner end, which has vertical passages.
The flat base
sections are connected to each other by means of tongue and groove joints. The
base
section and the flat base section are connected by a diagonal brace for
bracing. The circular
segments of the base section also have vertical passages. Connecting
cables/anchor rods
are inserted into the passages. If the foundation sections are to be made of
concrete, a flat
steel abutment ring is provided below the base elements in the area of the
vertical
passages. The foundation is mounted with the connecting cables/anchor rods and
the wind
turbine is fastened to the foundation. In addition, horizontal passages are
provided in base
elements and diagonal struts, in which connecting cables/anchor rods are also
arranged,
with which the elements of the foundation are horizontally prestressed. Only
through the
horizontal prestressing is the foundation completed in such a way that it can
bear loads.
Thus, EP 1 058 787 B1 discloses a foundation consisting of individual
prefabricated
concrete elements, with a surface section and a base section, whereby at least
these two
sections are connected to each other vertically and horizontally.
The disadvantage here is that considerable costs and labor are required for
connecting the
elements and producing the statically resilient foundation.
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EP 1 074 663 Al discloses a foundation for a wind turbine with a central body
as a base
with laterally extending star-shaped ribs/projections/beams bolted to it. Ribs
and central
body are horizontally bolted together on site. The parts are prefabricated
from concrete,
among other materials, and are delivered to the construction site by truck,
arranged by
crane and connected to each other horizontally on site via flanges and bolted
connections.
Furthermore, anchors are required on the outside of the ribs to ensure
sufficient load
transfer.
The disadvantage here is that here, too, considerable costs and labor are
required for
connecting the elements and producing the statically resilient foundation.
Furthermore,
additional anchors are necessary.
WO 2004/101898 A2 discloses a foundation for a wind turbine made of
prefabricated
concrete components, whereby either a central body is provided to which
surface bodies
are horizontally bolted, or the foundation consists exclusively of components
having both a
surface section and a base-like section, which are then horizontally connected
to each other
by bolting against flanges.
The disadvantage here is that here, too, considerable costs and labor are
required for
connecting the elements and producing the statically resilient foundation.
EP 2 182 201 Al discloses two different foundations for a wind turbine. In
both, a foundation
is erected from prefabricated concrete components after appropriate delivery
on site. Both
contain a flat section and a base-like section. In Variant 1, a central body
is provided. The
ribs/area elements are attached to this. When assembled, the ribs form a
polygonal body.
The central body has a projection which is embraced by a corresponding recess
on the ribs.
The ribs are additionally locked against the central body by means of a
lashing ring. Anchor
rods are provided on the surface headers for mounting the tower. In the second
variant, the
ribs have horizontally projecting anchor elements which, when assembled,
extend radially
into the center of the foundation. Plates are provided below and above the
anchors. In-situ
concrete is placed in the cavity thus formed to connect the anchors and form a
central body.
In both variants, horizontal connection is simplified. However, both the ribs
and the central
body have dimensions and masses that make transportation complicated.
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WO 2017/141095 Al and WO 2017/141098 Al also disclose a foundation for a wind
turbine.
This foundation is formed from prefabricated rib bodies, which have a base
section at their
inner end, on which the tower of the wind turbine is arranged. The ribs extend
radially
outward. In another embodiment, the sections between the ribs are filled with
plate elements
bolted against the ribs with flanges to form a plate. Centrally, instead of a
central body, a
steel sleeve is provided, which is connected to reinforcements provided inside
the ribs and
reinforcing beams provided in internal cavities. The ribs have a base plate.
On which a
diagonal reinforcing member and the base section are integrally arranged. The
base
sections are horizontally connected to each other via tongue and groove
elements.
Furthermore, the base sections have horizontal openings in which clamping
elements are
provided for horizontally connecting the base sections. Furthermore, anchor
rods for
connecting the tower to the foundation are cast in the base sections.
Furthermore, external
ground anchors are also disclosed.
The disadvantage here is that here, too, considerable costs and labor are
required for
connecting the elements and producing the statically resilient foundation.
WO 2019/115622 Al and WO 2019/201714 A2 disclose first successful foundations
for
wind turbines made of precast concrete elements for a steel tower and for a
concrete tower
for a wind turbine. The foundations have two sections. Rib elements are
provided, which
have a central section on which a base section is provided. The tower of the
wind turbine is
then arranged on the base section. The base section consists of individual
segments which
are connected to each other. By means of tendons provided in openings in the
central
section and in the elements of the base section, the rib elements and the base
elements
are braced together. Further developments of these foundations have resulted
in surprising
and particularly efficient improvements in the area of the base.
The objective of the invention is therefore to overcome the aforementioned
disadvantages
and to make foundations for wind turbines, in particular for wind turbines
with concrete
towers, economically erectable or erectable from prefabricated elements.
The objective according to the invention is solved in that a base is provided
which is formed
at least from the first vertically extending base-like section, from the at
least two support
sections of the second section and from the third vertically extending base-
like section, in
that the three sections form at least three layers arranged one above the
other, of which the
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upper and lower layers are formed from at least two ring-like layers and the
middle layer is
formed from at least one ring-like layer, in that the height of the upper
and/or lower layer is
smaller than the height of the middle layer, and in that the layers are
vertically braced to the
second section by means of at least two vertical tendons.
Such foundations according to the invention are suitable both for concrete
towers and for
steel towers. The advantage is that this type of foundation does not require
any horizontal
fasteners at all, while providing sufficient stability even in extreme load
situations.
Surprisingly, this is achieved in particular by the upper and lower layers
comprising at least
two ring-like layers in conjunction with bracing by prestressed tendons.
A further teaching of the invention provides that the height of the upper and
lower layers is
in total smaller than the height of the middle layer. Surprisingly, this makes
it possible to
achieve optimum load distribution in the foundation.
According to a further teaching of the invention, at least one of the layers
comprises at least
one prefabricated element, preferably reinforced concrete. Alternatively, it
is provided that
at least one of the layers comprises at least two precast elements, preferably
of reinforced
concrete. Further alternatively, it is provided that at least two adjacent
layers comprise at
least two prefabricated elements, preferably of reinforced concrete. This
facilitates the
standardized construction of the foundation and reduces the necessary number
of
transports to the construction site, in particular of in-situ concrete.
It is advantageous that the at least two elements are arranged butted and form
the ring-like
layer without horizontal fasteners in the vertical joints between the at least
two elements. It
is advantageous that the vertical joints are provided stress-free and/or that
the at least two
elements are arranged contact-free in the vertical joints. This in turn
facilitates the
standardized erection of the foundation and at the same time keeps costs low,
because the
prefabricated components in the area of the vertical butt joints, for example
at distances of
up to 3 cm, can be worked with tolerances customary in concrete construction
during
manufacture. Surprisingly, it has also been shown that such an arrangement
provides
sufficient stability in the foundation even in extreme load situations.
Another advantage is that the joints or vertical joints of two layers lying
directly one above
the other are not aligned. Surprisingly, it has been shown that it is possible
to break down
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the individual ring-type layers into individual elements and at the same time
achieve
sufficient stability even in extreme load situations in the foundation.
According to a further teaching of the invention, the prefabricated elements
of the first and/or
second sections are arranged connected to each other substantially without
horizontal
connecting means, preferably with vertical spacing between the prefabricated
elements.
A further teaching of the invention provides that the prefabricated elements
of the lower
and/or upper layer have an increased reinforcement in the normal direction
(tensile/compressive reinforcement) and/or that the prefabricated elements the
middle layer
have at least one increased reinforcement for dissipating shear loads, in
particular in the
radial direction The provision of the reinforcements in the manner described
above enables
a cost-effective construction of the foundation.
According to a further teaching of the invention, at least one horizontal
joint between the
prefabricated elements of the first and/or second section are arranged one on
top of the
other free of in-situ concrete and/or mortar. It has been shown that providing
horizontal
contact of the prefabricated elements when manufactured with sufficient
accuracy (small
tolerances in the horizontal direction of the prefabricated elements) causes
sufficient friction
in the horizontal joints due to the prestressing, so that sufficient stability
is provided in the
foundation even in extreme loading situations.
Another teaching of the invention provides that the prestressing by the at
least two tendons
is designed so that all horizontal joints between the layers are under
pressure in any
operating condition and in any extreme load condition of the wind turbine.
Hereby, in a
particularly simple manner, sufficient friction of the prefabricated elements
is effected in
particular in the horizontal joints between the prefabricated elements, so
that the foundation
is provided with sufficient stability even in extreme load situations, even
without material-
locking connections to the horizontal joints.
A further teaching of the invention provides that at least two ring-like
abutments, preferably
in the form of at least one abutment ring, are provided against which the
tendons act, at
least one abutment being arranged on the upper side of the first section and
at least one
abutment on the lower side of the third section. This provides in a simple
manner the
necessary load abutment for the tendons and the prestressing introduced
thereabove. It is
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advantageous that at least one abutment and/or at least one abutment ring
comprises at
least two prefabricated elements which are arranged in abutment with the ring-
like abutment
and/or abutment ring. This facilitates the transport of the prefabricated
elements.
Furthermore, it is advantageous that at least one abutment has at least two
layers arranged
one above the other. This makes it possible to erect the foundation in a
standardized
manner as a function of the applied prestressing. It is also advantageous that
the layers
each have at least two elements that are arranged butted, with the butts of
two layers lying
directly above one another not being arranged in alignment. This avoids time-
consuming
welding work on site and reduces the construction time of the foundation.
Furthermore, it
becomes possible in a simple way to adequately transfer the loads of the
prestressing via
the abutment constructed in this way depending on the foundation design.
A further teaching of the invention provides that the second section is formed
by at least
three horizontal elements, and that the horizontal elements can be arranged as
a function
of the parameters of the tower to be erected, in particular the tower radius.
It is
advantageous that the horizontal elements are arranged laterally spaced apart
from one
another, or that the horizontal elements are arranged laterally parallel
spaced apart from
one another. This makes it possible in a particularly simple manner to provide
a foundation
depending on the dimensions of the tower to be erected. In particular, it is
possible to create
foundations for different tower radii with one type of horizontal element by
shifting the
horizontal elements in parallel accordingly.
A further teaching of the invention provides that the elements of the at least
three layers of
the first section have at least two substantially vertical apertures, in each
of which a tension
member, preferably a threaded rod or an anchor bolt with counter elements, is
arranged.
This makes it possible to provide the foundation quickly and cost-effectively
in a particularly
simple manner. When providing the openings, precise work with only minor
deviations is
necessary so that the tendons can be used and, at the same time, to effect the
mountability
of the prefabricated elements. This is facilitated in particular by the
vertical spacing of the
elements in a particularly simple manner.
In the following, the invention is explained in more detail by means of
embodiment examples
in connection with a drawing. Thereby show:
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Fig. 1 a sectional view of a preferred embodiment of a
foundation according to
the invention
Fig. 2 a spatial view of Fig. 1,
Fig. 3 atop view of Fig. 1,
Figs. 4a to 4e Views of a horizontal element according to the
invention,
Fig. 5a a plan view of arranged surface elements of the
foundation according to
the invention,
Fig. 5b detailed view of Fig. 5a,
Fig 6a to 8b Views of base segments according to the invention
in plan view and as a
spatial view,
Fig 9 a top view of an upper abutment ring according to
the invention as an
upper and/or lower connection for the tendons of the foundation according
to the invention,
Fig. 10 an abstracted spatial detail view of Fig. 11,
Fig. 11 a sectional view through your design of the upper
and lower abutment ring
according to Fig. 9 with mounted tendons,
Fig. 12a, 12b a top view and a side view of a cover plate
according to the invention, and
Fig. 13a to 13d different arrangement options to Fig. 5a.
In Fig. 1, a foundation 10 according to the invention is arranged in a
sectional view in a pit
101 in the ground 100, possibly on a possibly compacted cleanliness layer 102.
The
foundation 10 thereby has a first section 11, which is arranged on a, second
section 12.
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Furthermore, a third section 12a is provided below the second section 12,
which is provided
in a depression 105 of the excavation 101.
The three sections 11, 12, 12a form a base 20, which in turn is constructed
from several
layers 13, 16, 17, the layers 13, 16, 17 being constructed here, for example,
from 5 layers
13a, 13b, 16a, 17a, 17b. If necessary, further layers can be provided.
The layers 13a, 13b, 17a, 17b are constructed from closed base sections 14,
which in turn
are constructed from individual base segments 33, 34, 35 (see Figs. 6a to 8b).
The base
sections 14 are preferably designed here as circular rings, so that the base
section 11 has
an interior space 15. An alternative structure, e.g., a polygonal structure,
is possible.
The layers 13, 16, 17 are preferably composed here of the individual layers
13a, 13b, 16a,
17a, 17b, the layers 13a, 13b, 17a, 17b themselves being composed of matching
base
segments 33, 34, 35. The uppermost layer 13 has two layers 13a, 13b. The top
layer 13a
is composed of base segments 33, for example as shown in Fig. 6a, 6b, with a
height H.
On their upper side 36, for example, a recess 37 is provided here, in which a
connecting
flange for the tower of the wind turbine or directly the lowermost segment of
the tower of the
wind turbine is placed (not shown). In the recesses 37, the apertures 18a for
tendons (not
shown of the tower of the wind turbine are provided. Furthermore, apertures 18
are provided
for tendons 19. In the area of the apertures 18, abutment flanges 51, for
example as shown
in Fig. 9, are arranged on the upper side 36, against which the tendons 19 are
braced via
the counter elements 21.
Below this, a layer 13b is provided, which is composed of base segments 34
(Figs. 7a, 7b)
with a height I, which are also provided with apertures 18 for the tendons 19
and apertures
18a. The height I can be identical to the height H of the base segments 33 and
is preferably
the same.
Below this is the layer 16a as the middle layer 16. This is formed by the
bodies 30 of the
support sections 25 of the horizontal segments 22. These have the height K.
The bodies 30
are also provided with openings 18 for the tendons 19.
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Provided below this, and thus below the horizontal elements 22, is the lower
layer 17 with
the layers 17a, 17b, which are formed from base segments 35 with a height J.
The base
segments 35 are also provided with openings 18 for the tendons 19.
The base segments 33, 34, 35 and the body 30 of the horizontal element 22 are
preferably
very precisely designed with respect to the height H, I, J, K, i.e., with the
smallest possible
height deviations, in order to bring about the largest possible contact
surface of the base
segments 33, 34, 35 and the body 30 on one another when these are mounted on
top of
one another to form the base 20 and are prestressed.
The height H, I, J of the base segments 33, 35 is designed in such a way that,
in the installed
state, it is essentially only loaded in tension/compression, i.e., it is
subjected to a load in the
normal direction. The reinforcement is also designed for this purpose (not
shown),
essentially comprising reinforcement in the normal direction. Preferably, the
heights H, I and
J are the same.
The height K of the beams 30 is designed in such a way that, in the installed
state, it is
essentially only loaded in shear. The reinforcement can also be designed for
this (not
shown), which essentially comprises reinforcement in the radial direction,
particularly
preferably in the form of stirrups.
The arrangement of segments 33, 34, 35 and body 30 to form ring-like layers
13a, 13b, 16a,
17a, 17b and the arrangement layers 13a, 13b, 16a, 17a, 17b one above the
other to form
layers 13, 16, 17, which then form base 20, is shown spatially in Fig. 2. The
base segments
33, 34, 35 and the bodies 30 are provided butted side by side so that vertical
gaps 38, 40
exist between them. These are preferably designed as gaps, for example, with a
thickness
of several millimeters, e.g., 30 mm. These vertical joints 38, 40 are
preferably not filled with
mortar or in-situ concrete. Furthermore, preferably no horizontal connecting
means are
provided.
Furthermore, the vertical joints of the individual layers 13a, 13b, 16a, 17a,
17b are
preferably provided such that the vertical joints 38,40 of adjacent layers
13a, 13b, 16a, 17a,
17b are not aligned, i.e., are not arranged one above the other. As shown in
Fig. 2, it is
advantageous if the vertical joints 38 are always arranged offset by
substantially the same
value clockwise or counterclockwise.
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Horizontal joints 39 exist between layers 13a, 13b, 16a, 17a, 17b and are
preferably not
filled with mortar or in-situ concrete.
The base segments 33, 34, 35 and the bodies 30 have vertical apertures 18 in
which
tendons 19, for example anchor rods or reinforcement rods 19 with counter
elements such
as nuts 21 in conjunction with washers 21a are provided to pretension the
foundation 10
when the foundation 10 is assembled. These, together with abutments 51
composed of
flange plates 52, form an anchor cage (not shown). Part of the upper abutment
51 can also
be the connection adapter 53 for the tower, for example if the tower is a
steel tower.
The second section 12 is flat. Alternatively, however, it can also be
implemented in a star
shape. A top view of the foundation 10 is shown in Fig. 3. Fig. 2 shows a
spatial view of the
foundation 10. The second section 12 is made of horizontal elements 22 in the
form of rib
elements. These are shown in Figs. 4a to 4e. These extend radially outward as
viewed from
the interior 15.
They have a base plate 23 that is trapezoidal in shape, for example, so that
all assembled
base plates form a polygonal surface (see Figs. 3, 5a) that approximates a
circular shape.
Alternatively, circular segments or a mixed form of circular segment and
trapezoidal shape
are also possible. Spaces B can preferably be provided between side walls 44
of the base
plates 23, depending on the diameter of the tower to be erected.
At the inner end 24 of the base plate 23, a support section 25 is provided
having a body
and sidewalls 29 that substantially preferably corresponds to the base 20 of
the first section
11. Apertures 18 may also be provided in the support section 25.
Alternatively, reinforcing
bars or anchor rods 19 may be installed in the support section 25 in alignment
with the
apertures 18 in the first section 11 and extending outwardly from the concrete
of the
pedestal-like section 25 of the horizontal member 22. The base 20 with its at
least one base
element 14 is arranged on the support section 25.
If a tower is erected by means of pretensioning elements (not shown) and
tensioned
accordingly, then, as shown here, it is advantageous to provide a recess 30a
in the body
30 in order to check the counter elements of the tower pretension ing and to
retension them
if necessary. Preferably, the apertures 18a open into the area of the recess,
as this is shown
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here. Furthermore, the apertures 18a are preferably provided at an incline so
that the tower
pretensioning elements can be passed directly therethrough.
Perpendicular to the base plate is the stiffening wall 26, the height of which
decreases, for
example, towards the outer end 27 of the base plate 23.
The base plate 23 is parallel tapered with respect to the side surfaces 29 of
the body 30 of
the support section 25. The parallel taper 31 is shown by the arrow D in Fig.
4c. This
preferably achieves a reduction in material. The body 30 has a transition
region 32 with
which the stiffening wall 26 is connected to the support section 25 in a
reinforcing manner.
Between the side surfaces 29 of the support sections 25, as shown in Fig 5b as
section E
to Fig. 5a, a distance C is preferably provided as a vertical joint 40 when
the horizontal
elements 22 are arranged, which is preferably designed as an air gap. This
results in vertical
joints 40, which are also preferably not filled with mortar or in-situ
concrete. Furthermore,
preferably no horizontal connecting means are provided.
An upwardly open cavity 28 is formed between two adjacent stiffening walls 26,
into which
fill soil 104 can be placed, thereby providing a surcharge load on the second
section 12 of
the foundation 10.
To allow the cavities 28 to be filled with backfill soil 104 and to prevent it
from entering the
interior 15, barrier elements (not shown) can be placed against the body 30 of
the support
section 25 or transition area 32.
Furthermore, cover plates 48 (Figs. 12a, 12b) are provided which are placed on
two
adjacent base plates 23 to cover the distance B between two side surfaces 44
so that the
backfill soil 104 cannot enter or pass through the distance B. The cover
plates 48 have a
tapered section 49 that is adapted to the transition area 32. The cover plate
48 allows the
full ballast load of the backfill soil 104 to be applied to the second section
12 by insertion
into the cavity 28.
The interior space 15 may be backfilled with backfill soil 104 after
completion of the
foundation 10 and covered with a cover element '(not shown).
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As shown in Figs. 13a to 13d, it is possible to form a second section with a
horizontal
element 22 that has differently sized interior spaces 15 by moving the
horizontal elements
22 inward or outward along a ray extending from the center point, as shown by
the double
arrow A in Fig. 13d. Inwardly, this is limited by the fact that the side
surfaces 44 of the base
plates 23 of the horizontal elements 22 are in contact. Outwardly, this
depends on the radius
45 of the tower to be erected, which is shown by a circle 46 in Figs. 14a to
14d. The distance
B is preferably the same over the entire length of the side surfaces 44 from
the inner end
24 to the outer end 27, so that two side surfaces 44 are arranged parallel to
each other.
Through this, foundations for towers with different diameters can be erected
in a simple
manner preferably with a single horizontal element 22.
To provide the necessary bracing between the layers 13, 16, 17 of the first,
second and
third sections 11, 12, 12a, an anchor cage (not shown) is formed, which is
formed by an
upper and a lower abutment 51 shown in Fig. 9, which are connected to tendons
19, for
example in the form of anchor bars or reinforcement bars, and counter elements
21, for
example nuts.
The upper and lower abutment elements 51 are composed, for example, of an
abutment
ring 51a. The abutment ring 51a can be made of individual flange plates 52,
which are
arranged butted against each other, as shown in Fig. 10 as an indicated anchor
cage
section. Furthermore, several flange plates 52 can be arranged on top of each
other, as
shown in Fig. 10 and Fig. 11. In this case, these are then preferably arranged
in such a way
that their vertical joints 56 do not overlap in adjacent layers of the flange
plates 52.
Preferably, the flange sheets 52 are not welded to each other, but rest on or
against each
other. The flange plates 52 have apertures 57 and can be provided with
different widths and
different numbers of rows of apertures 57 per flange plate 52, 55.
Preferably, the abutment ring 51b may be integral with the connection adapter
53 as a
flange plate 52.
*****
CA 03194703 2023- 4- 3
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List of reference signs
foundation 35 base segment
11 first section 36 top side
12 second section 37 recess
12a third section 38 vertical joint
13 upper layer 39 horizontal joint
13a layer 40 vertical joint
13b layer 44 side wall
14 base section 45 radius
Interior space 46 circle
16 middle layer 48 cover plate
16a layer 49 tapered section
17 lower layer 51 abutment
17a layer 52 flange plate
17b layer 56 vertical joint
18 opening 100 ground
19 tendon/anchor rods 101 pit
socket 102 cleanliness layer
21 counter element/nut 103 cover element
21a washer 104 backfill soil
22 horizontal element/ rib element A Shift direction
23 base plate B distance
24 inner end C distance
bearing section D arrow of the parallel taper
26 stiffening wall E detailed view
27 external end H height
28 cavity I height
29 side wall J height
body K Height
30a Recess
31 parallel taper
32 transition area
33 upper base segment
34 middle base segment
CA 03194703 2023- 4- 3
