Base for wind turbine
阅读说明:本技术 用于风力机的基座 (Base for wind turbine ) 是由 G·普拉斯 C·施里费 于 2018-12-12 设计创作,主要内容包括:本发明涉及用于风力机的基座,基座具有基本上预制的、优选加筋混凝土制成的元件,包括竖直延伸的底座状的第一部段和基本上水平延伸的作为与地面接触的基座体的第二部段,在第一部段上能布置风力机的塔架,第一部段布置在第二部段上方并且具有至少一个封闭的、优选套筒形的底座元件,其构造为环形或多边形的,而第二部段由至少两个水平元件形成,其分别具有至少一个底座部段,第一部段的至少一个底座元件和第二部段的水平元件的底座部段具有基本上竖直的通孔,通孔彼此对齐地安装,在通孔中设置有基本上竖直的夹紧元件、优选螺杆,第一部段的至少一个底座元件和第二部段的至少两个水平元件通过基本上竖直的预紧元件彼此预紧,使得不需要另外的固定器件、尤其是水平固定器件来传递风力机的载荷。(The invention relates to a foundation for a wind turbine, comprising a substantially prefabricated, preferably reinforced concrete element, comprising a first, substantially horizontally extending, foundation-like first section, on which a tower of the wind turbine can be arranged, and a second, substantially horizontally extending base body, which is in contact with the ground, wherein the first section is arranged above the second section and has at least one closed, preferably sleeve-shaped base element, which is of annular or polygonal design, and the second section is formed from at least two horizontal elements, each of which has at least one base section, wherein the at least one base element of the first section and the base sections of the horizontal elements of the second section have substantially vertical through holes, which are mounted in alignment with one another, wherein substantially vertical clamping elements, preferably screws, are arranged in the through holes, and wherein the at least one base element of the first section and the at least two horizontal elements of the second section are prestressed against one another by means of a substantially vertical prestressing element So that no additional fixing means, in particular horizontal fixing means, are required for transferring the load of the wind turbine.)
1. Foundation for a wind turbine, having a substantially prefabricated element, preferably an element made of reinforced concrete, comprising a first section of a vertically extending foundation-like construction, on which a tower of the wind turbine can be arranged, and a second section of a substantially horizontally extending foundation body, which is in contact with the ground, wherein the first section is arranged above the second section and has at least one closed, preferably sleeve-shaped, foundation element, which is of annular or polygonal configuration, and the second section is formed by at least two horizontal elements, each having at least one foundation section, the at least one foundation element of the first section and the foundation section of the horizontal element of the second section having substantially vertical through-holes, which are mounted in alignment with one another, a substantially vertical clamping element, preferably a threaded rod, is arranged in the through-opening, characterized in that the at least one base element of the first section and the at least two horizontal elements of the second section are pretensioned against one another by means of a substantially vertical pretensioning element, so that no additional securing means, in particular horizontal securing means, are required for transmitting the load of the wind turbine.
2. The foundation for a wind turbine according to claim 1, wherein at least one abutment is provided below or inside the second section, to which the substantially vertical clamping element is arranged and clamped, and/or an abutment is provided above or inside the first section, to which the substantially vertical clamping element is arranged and clamped, wherein the upper abutment is preferably a flange of a tower of a wind turbine.
3. The foundation for a wind turbine according to claim 1 or 2, wherein the features of claims 4 to 30 are combined.
4. Foundation for a wind turbine, having a substantially prefabricated element, preferably an element made of reinforced concrete, comprising a first section of a vertically extending foundation-like construction, on which a tower of the wind turbine can be arranged, and a second section of a substantially horizontally extending foundation body, which is in contact with the ground, wherein the first section is arranged above the second section and has at least one closed, preferably sleeve-shaped, foundation element, which is of annular or polygonal configuration, and the second section is formed by at least two horizontal elements, each having at least one foundation section, the at least one foundation element of the first section and the foundation section of the horizontal element of the second section having substantially vertical through-holes, which are mounted in alignment with one another, a substantially vertical clamping element, preferably a threaded rod, is arranged in the through-opening, characterized in that the closed base element of the first section consists of at least two arc-shaped sections.
5. The foundation for a wind turbine as claimed in claim 4, wherein the arc segments overlap in the connection region and the through holes also overlap in the overlap region.
6. The foundation for a wind turbine as claimed in claim 5, wherein the arc segments abut each other with substantially vertical abutment surfaces in the connection region.
7. The foundation for a wind turbine as claimed in any one of claims 4 to 6, wherein a plurality of substantially horizontal stiffening elements project from the curved section in the connection area, the stiffening elements overlapping in the connection area.
8. The foundation for a wind turbine as claimed in one of the claims 4 to 7, characterized in that the curved section tapers in the connecting region in terms of the curved section height and/or the curved section width, preferably in that a through-opening is provided in the tapering section.
9. The foundation for a wind turbine as claimed in claim 8, wherein the horizontal stiffening elements overlap in the tapering section.
10. The foundation for a wind turbine as claimed in claim 8 or 9, wherein the tapering region is filled with mortar.
11. The base for a wind turbine according to any one of claims 4 to 7, wherein the features of claims 1 or 2 and 12 to 30 are combined.
12. Foundation for a wind turbine, having a substantially prefabricated element, preferably an element made of reinforced concrete, comprising a first section of a vertically extending foundation-like construction, on which a tower of the wind turbine can be arranged, and a second section of a substantially horizontally extending foundation body, which is in contact with the ground, wherein the first section is arranged above the second section and has at least one closed, preferably sleeve-shaped, foundation element, which is of annular or polygonal configuration, and the second section is formed by at least two horizontal elements, each having at least one foundation section, the at least one foundation element of the first section and the foundation section of the horizontal element of the second section having substantially vertical through-holes, which are mounted in alignment with one another, a substantially vertical clamping element, preferably a threaded rod, is arranged in the through-opening, characterized in that a reinforcing element is provided in the first section.
13. The foundation for a wind turbine as claimed in claim 12, wherein the reinforcement element has no through-hole and/or is arranged in the first section without fixing means.
14. The foundation for a wind turbine as claimed in claim 12 or 13, wherein the reinforcement element is configured as a sleeve having a clear inner diameter preferably substantially corresponding to the clear inner diameter of the first section and/or the second section.
15. The foundation for a wind turbine as claimed in any one of the claims 12 to 14, characterized in that the reinforcement element is surrounded by a base element having substantially the same or a greater height, whereby the surrounding base element and the reinforcement element preferably have substantially the same wall thickness as the base element arranged above and/or below it.
16. The base for a wind turbine according to any one of claims 12 to 15, wherein the features of claims 1 to 11 and 17 to 30 are combined.
17. Foundation for a wind turbine, having a substantially prefabricated element, preferably an element made of reinforced concrete, comprising a first section of a vertically extending foundation-like construction, on which a tower of the wind turbine can be arranged, and a second section of a substantially horizontally extending foundation body, which is in contact with the ground, wherein the first section is arranged above the second section and has at least one closed, preferably sleeve-shaped, foundation element, which is of annular or polygonal configuration, and the second section is formed by at least two horizontal elements, each having at least one foundation section, the at least one foundation element of the first section and the foundation section of the horizontal element of the second section having substantially vertical through-holes, which are mounted in alignment with one another, a substantially vertical clamping element, preferably a threaded rod, is arranged in the through-opening, characterized in that a reinforcing element is provided in the second section.
18. The foundation for a wind turbine as claimed in claim 17, wherein the reinforcement element has no through-holes and/or is arranged in the second section without fixing means.
19. The foundation for a wind turbine as claimed in claim 17 or 18, wherein the reinforcement element is configured as a sleeve having a clear inner diameter preferably substantially corresponding to the clear inner diameter of the first section and/or the second section.
20. The foundation for a wind turbine as claimed in any one of claims 16 to 19, wherein the reinforcement element is surrounded by a base section of the at least two horizontal elements having substantially the same or a greater height.
21. The base for a wind turbine according to any one of claims 17 to 20, wherein the features of claims 1 to 16 and 22 to 30 are combined.
22. Foundation for a wind turbine, having a substantially prefabricated element, preferably an element made of reinforced concrete, comprising a first section of a vertically extending foundation-like construction, on which a tower of the wind turbine can be arranged, and a second section of a substantially horizontally extending foundation body, which is in contact with the ground, wherein the first section is arranged above the second section and has at least one closed, preferably sleeve-shaped, foundation element, which is of annular or polygonal configuration, and the second section is formed by at least two horizontal elements, each having at least one foundation section, the at least one foundation element of the first section and the foundation section of the horizontal element of the second section having substantially vertical through-holes, which are mounted in alignment with one another, a substantially vertical clamping element, preferably a threaded rod, is arranged in the through-opening, characterized in that a vertically extending base-like configured further section is provided, which is arranged below the second section and has at least one closed base element, preferably a sleeve-shaped base element, and which is necessary for transmitting the load of the wind turbine.
23. The foundation for a wind turbine as claimed in claim 22, wherein the closed base element of the further section is comprised of at least two arcuate sections.
24. The foundation for a wind turbine as claimed in claim 23, wherein the arc segments overlap in the connection region and the through holes also overlap in the overlap region.
25. The foundation for a wind turbine as claimed in claim 23, wherein the arc segments abut each other with substantially vertical abutment surfaces in the connection region.
26. The foundation for a wind turbine as claimed in any one of claims 22 to 25, wherein a plurality of substantially horizontal stiffener elements project from the arch segment in the connection region, the stiffener elements overlapping in the connection region.
27. The foundation for a wind turbine as claimed in any one of the claims 22 to 26, characterized in that the curved section tapers in the connection region in terms of the curved section height and/or the curved section width, preferably in that a through-opening is provided in the tapering section.
28. The foundation for a wind turbine of claim 27, wherein the horizontal stiffening elements overlap in the tapered section.
29. The foundation for a wind turbine as claimed in claim 27 or 28, wherein the tapered region is filled with mortar.
30. The foundation for a wind turbine as claimed in any one of claims 22 to 29, wherein the features of claims 1 to 21 are combined.
31. The foundation for a wind turbine as claimed in any one of claims 1 to 30, wherein there is a vertical and horizontal joint between the elements in such a way that a vertical and/or horizontal spacer is arranged between the elements.
32. The foundation for a wind turbine as claimed in any one of claims 1 to 31, wherein vertical and/or horizontal joints between the elements are at least partially mortar filled.
Technical Field
The invention relates to a foundation for a wind turbine, comprising a substantially prefabricated element, preferably made of reinforced concrete, on which a tower of the wind turbine can be arranged, a first section of a vertically extending foundation-like structure, which is arranged above the second section and has at least one closed, preferably sleeve-shaped, foundation element, which is designed in an annular or polygonal manner, and a second section of a substantially horizontally extending foundation body, which is in contact with the ground and is formed by at least two horizontal elements, each of which has at least one base section, the base sections of the horizontal elements of the first and second sections having substantially vertical through-holes, which are arranged in alignment with one another, in which through-holes substantially vertical clamping elements are arranged, A screw is preferred.
Background
The foundation for a wind turbine is constructed primarily as a cast-in-place concrete foundation. For this purpose, a pit is cut into the construction site, which is provided with a bedding (Sauberkeitsschicht). The form and rebar are then constructed and the whole filled with concrete on site. Planar bodies, possibly with a base, are built up here, see for example US 20160369520 a1 or WO 2008/036934 a 2. In addition to the transport costs associated with supplying concrete to the forms and reinforcing bars, this is also a significant job site. Furthermore, quality assurance is complicated and there are problems according to weather conditions. Furthermore, the disassembly after the end of the life of the wind turbine is expensive and quite complex.
Thus, there is a need in principle for constructing a wind turbine foundation from prefabricated elements, whereby the above-mentioned problems can be reduced or eliminated. In principle, it is advantageous that the components can be produced in a standardized manner under defined conditions during the prefabrication. The workload on the site is also reduced. For this purpose, various approaches are described in the prior art.
For example WO 2008/036934 a2 shows a combination of prefabricated elements and conventional formwork/rebar structures. The above-mentioned disadvantages are thereby reduced only insignificantly.
Other solutions for producing wind turbine foundations from prefabricated components are shown in the prior art as follows:
EP 1058787B 1 discloses a foundation for a wind turbine in order to build an offshore wind turbine, which is transported with complete pre-installation (i.e. including the foundation) and is sunk as a whole into a construction site on the seabed. The foundation has a plurality of individual prefabricated segments, which may be made of concrete. A planar section and a base section are disclosed. The base section comprises a ring and the flat section comprises a plurality of individual base elements which are trapezoidal in the base plane, the base section being mounted vertically on the flat section at the inner end, the flat section having a vertical through-opening. The planar base sections are connected to one another by means of a tongue-and-groove connection. The base section and the planar base section are connected by diagonal braces for reinforcement. The circular arc section of the base section also has a vertical through-opening. Connecting cables/anchor rods are inserted into these vertical penetrations. If a base part made of concrete is provided, a flat carrier ring made of steel is provided in the region of the vertical through-opening below the foundation element. The base is installed and the wind turbine is secured to the base by connecting steel cables/anchor rods. In addition, horizontal passages are provided in the base element and diagonal struts, in which horizontal passages connecting cables/anchor rods are also arranged, with which the elements of the base are horizontally pretensioned. The base which can be subjected to the load is not completed until the horizontal pretensioning. Thus, EP 1058787B 1 discloses a foundation comprising individual precast concrete parts, which foundation comprises a planar section and a base section, at least the two sections being connected to each other vertically and horizontally.
The disadvantage here is that considerable costs and a large amount of work are required to connect the elements and to produce a base that can withstand the static loads.
EP 1074663 a1 discloses a foundation for a wind turbine, which comprises as a base a central body comprising laterally extending star-shaped arranged ribs/projections/supports screwed thereto. The rib and central body are screwed horizontally to each other on site. Furthermore, these components are prefabricated from concrete and transported to the construction site by means of trucks, arranged via cranes and connected to each other horizontally on site via flanges and swivels. Furthermore, anchors are also required outside the ribs in order to ensure sufficient load transfer (latbabtrag).
The disadvantage here is that here too great costs and a great deal of effort are required to connect the components and to produce a base that can withstand the static loads. Additional anchoring is also required.
WO 2004/101898 a2 discloses a foundation for a wind turbine, which comprises prefabricated concrete parts, wherein either a central body is provided, to which a planar body is screwed horizontally, or the foundation consists only of components having both planar and base-like sections, wherein these components are then connected to one another horizontally by means of screwed connections to flanges.
The disadvantage here is that here too great costs and a great deal of effort are required to connect the components and to produce a base that can withstand the static loads.
EP 2182201 a1 discloses two different foundations for a wind turbine. In both types of foundations, the foundation is built on site from precast concrete parts after the respective delivery. Both bases comprise a planar section and a base-like section. In embodiment 1, a central body is provided. A rib/planar element is disposed onto the central body. The rib is mounted to form a polygonal body. The central body has a protrusion surrounded by a corresponding recess on the rib. The rib is additionally locked to the central body by means of a lashing ring. The planar body is provided with an anchoring rod for mounting the tower. In a second variant, the ribs have horizontally projecting anchoring elements which, in the installed state, extend radially to the center of the base. Plates are arranged below and above the anchoring piece. Cast-in-place concrete is introduced into the cavity thus formed, so as to connect the anchors to one another and form the central body. Horizontal connections are simplified in both scenarios. However, both the ribs and the central body have dimensions and qualities that make transportation cumbersome.
WO 2017/141095A 1 and WO 2017/141098A 1 also disclose a foundation for a wind turbine. The foundation is formed by prefabricated ribs which have on their inner ends a foundation section 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 to make one plate, which are screwed to the ribs with flanges. Instead of the central body, a steel sleeve is provided in the middle, which steel sleeve is connected to the reinforcing bars arranged inside the ribs and to the reinforcing beams arranged in the inner hollow space. The rib has a base plate. The diagonal reinforcing element and the base section are arranged integrally on the base plate. The base sections are connected to each other horizontally via tongue and groove elements. The base sections furthermore have horizontal openings, in which clamping elements for horizontally connecting the base sections are arranged. Furthermore, an anchor rod for connecting the tower to the foundation is injected in the base section. In addition, an externally located ground anchor is also disclosed.
The disadvantage here is that here too great costs and a great deal of effort are required to connect the components and to produce a base that can withstand the static loads.
Disclosure of Invention
The object of the present invention is therefore to overcome the above-mentioned disadvantages and to enable a base for a wind turbine to be constructed economically from prefabricated elements.
The object is achieved by the different solutions of the
In a first solution according to the invention, it is provided that the at least one base element of the first section and the at least two horizontal elements of the second section are prestressed against each other by means of a substantially vertical prestressing element, so that no additional fastening means, in particular horizontal fastening means, are required for transmitting the load of the wind turbine.
It has surprisingly been shown that this can be achieved simply by omitting the horizontal connecting means.
A further teaching of the invention provides that at least one abutment is provided below or inside the second section, to which the substantially vertical clamping element is arranged and clamped, and/or that an abutment is provided above or inside the first section, to which the substantially vertical clamping element is arranged and clamped, wherein the upper abutment is preferably a flange of a tower of a wind turbine. This ensures a reliable clamping or pretensioning in a simple manner.
An equivalent second solution according to the invention provides that the closed base element of the first section is composed of at least two arc-shaped segments. This allows simple transport even in sizes that can only be achieved with special transport or cannot be achieved at all.
Another teaching of the invention provides that the arc segments overlap in the connecting region and that the through-openings also overlap in the overlapping region. A simple and reliable connection can thereby be provided.
According to a further teaching of the present invention, the arcuate segments have a substantially vertical contact surface in the connecting regionAre adjacent to each other. A simple and reliable connection can thereby be provided.
Another teaching of the invention provides that substantially horizontal stiffening elements project from the curved sections in the connecting region, the stiffening elements overlapping in the connecting region. A simple and reliable connection can thereby be provided.
A further teaching of the invention provides that the arc segments taper in the connecting region with respect to the arc segment height and/or the arc segment width, preferably that a through-opening is provided in the tapering section. Another teaching of the invention provides that the horizontal stiffening elements overlap in the tapering section. Another teaching of the present invention provides that the tapering region is filled with mortar. It has surprisingly been found that a particularly load-bearing and cost-effective connection is thereby provided when an arc-shaped section is provided.
An equivalent third solution according to the invention provides that a reinforcing element is provided in the first section. It has surprisingly been found that an increase in stability beyond horizontal in the base can be achieved simply in the case of a sectionalised (segmented) construction of the base by providing reinforcement elements, in particular in the base section.
A further teaching of the present invention provides that the reinforcing element has no through-opening and/or is arranged in the first section without a fastening means. A further teaching of the present invention provides that the reinforcement element is configured as a sleeve, the clear inner diameter of which preferably substantially corresponds to the clear inner diameter of the first and/or second section.
A further teaching of the invention provides that the stiffening element is surrounded by a base element having substantially the same or a greater height, so that the surrounding base element and the stiffening element preferably have substantially the same wall thickness as the base element arranged above and/or below it.
According to an equivalent fourth solution of the invention, provision is made for a reinforcing element to be provided in the second section. It has surprisingly been found that by providing a reinforcing element, in particular in the second section, an ultra-horizontal increase in stability can be achieved in the base simply in the case of a segmented construction of the base.
A further teaching of the invention provides that the reinforcing element has no through-opening and/or is arranged in the second section without a fastening means. A further teaching of the present invention provides that the reinforcement element is configured as a sleeve, the clear inner diameter of which preferably substantially corresponds to the clear inner diameter of the first and/or second section.
Another teaching of the present invention provides that the reinforcement element is surrounded by base sections of the at least two horizontal elements having substantially the same or a greater height.
An equivalent fifth solution according to the invention provides that a further section of vertically extending base-like formation is provided, which is arranged below the second section and has at least one closed base element, preferably a sleeve-shaped base element, and which is necessary for transmitting the loads of the wind turbine. By providing a pedestal-like section below the second section, the stability of the base can also be increased, surprisingly and in a simple manner, over-horizontally.
A further teaching of the present invention provides that the closed base element of the further section comprises at least two arc-shaped sections. This allows simple transport even in sizes that can only be achieved with special transport or cannot be achieved at all.
Another teaching of the invention provides that the arc segments overlap in the connecting region and that the through-openings also overlap in the overlapping region. A simple and reliable connection can thereby be provided.
Another teaching of the invention provides that the arc segments adjoin one another in the connecting region with substantially vertical contact surfaces. A simple and reliable connection can thereby be provided.
Another teaching of the invention provides that substantially horizontal stiffening elements project from the curved sections in the connecting region, the stiffening elements overlapping in the connecting region. A further teaching of the invention provides that the arc segments taper in the connecting region with respect to their height and/or their width, preferably with through-openings being provided in the tapering section. Another teaching of the invention provides that the horizontal stiffening elements overlap in the tapering section. Another teaching of the present invention provides that the tapering region is filled with mortar. It has surprisingly been found that a particularly load-bearing and cost-effective connection is thereby provided when an arc-shaped section is provided.
Another teaching of the invention with regard to all solutions of the invention provides that vertical and horizontal joints are present between the elements in such a way that vertical and/or horizontal spacers are arranged between the elements. Another teaching of the invention with regard to all solutions of the invention provides that the vertical and/or horizontal joints between the elements are at least partially filled with mortar. Thereby facilitating the stability of the base, since the remaining measures are supported with the provision of an integral connection.
Drawings
The invention is explained in more detail below with the aid of embodiments in conjunction with the drawings. Here:
figures 1 to 6b show views and details of a first embodiment of a base according to the invention;
figures 7 to 14b show views and details of a second embodiment of a base according to the invention;
figures 15 to 20b show views and details of a third embodiment of a base according to the invention; and
fig. 21 to 26 show views and details of a fourth embodiment of the base according to the invention.
Detailed Description
Fig. 1 to 6b show a first embodiment of a
The first portion 11 is designed as a base 20 (see fig. 4a to 4d) comprising a
The
The
On the
On the
The reinforcing
A third section is preferably provided here below the
Spacers (not shown) may be arranged between the
Fig. 7 to 14b show a second embodiment of a
The first portion 11 is designed as a base 20 (see fig. 10a to 10f) comprising a
The reinforcing element 30 (fig. 11a, 11b) is designed as a one-piece component. The reinforcing element is here preferably provided as a sleeve with an
As a height compensation or for reinforcement, a
The
On the
To further reinforce the second portion, in particular vertically, a plate 33 (see fig. 7 and 13a, 13b) can be provided on the
A third section 13 is preferably provided here below the
Below the third portion 13, a cavity 105 is provided into which an anchor rod/screw 19 or another alternative fixing means (a wire cable or the like) opens and to which, for example, a nut is screwed as a fixing means 31 in the form of a locking and pretensioning means. The cavity 105 is filled with cast-in-place concrete for reasons of corrosion protection of the fixing means.
Spacers (not shown) may be arranged between the
Fig. 15 to 20b show a third embodiment of the base 10 according to the invention. In the cross-sectional view of fig. 15, the foundation is arranged on a bedding 102 in a foundation pit 101 in the
The first portion 11 is designed as a
The
On the
A third section 13 is preferably provided here below the
Furthermore, the third section 13 also forms a support for the fastening element 31 of the anchor rod 19 with its
Below the third portion 13, a cavity 105 is provided into which an anchor rod/screw 19 or another alternative fixing means (a wire cable or the like) opens and to which, for example, a nut is screwed as a fixing means 31 in the form of a locking and pretensioning means. The cavity 105 is filled with cast-in-place concrete for reasons of corrosion protection of the fixing means.
Spacers (not shown) may be arranged between the
Fig. 21 to 26 show a fourth embodiment of the base 10 according to the invention, similar to the third embodiment. In the cross-sectional view of fig. 21, the foundation is arranged on a bedding 102 in a foundation pit 101 in the
The first portion 11 is designed as a
A particularly preferred connection of the
The
On the
A third section 13 is preferably provided here below the
In addition, the third section 13 also forms a support for the fastening element 31 of the anchor rod 19 with its
Below the third portion 13, a cavity 105 is provided into which an anchor rod/screw 19 or another alternative fixing means (a wire cable or the like) opens and to which, for example, a nut is screwed as a fixing means 31 in the form of a locking and pretensioning means. The cavity 105 is filled with cast-in-place concrete for reasons of corrosion protection of the fixing means.
Spacers (not shown) may be arranged between the
List of reference numerals
10
11 first section/
12
13 third section 31 fixing element
14
14a
15 outer end of the
16
17
18-via 37 connection device
19
20
21
22 horizontal element/rib element 101 foundation pit
23 substrate 102 pad layer
24 inner end 103 recess
25 base section 104 fill
26 reinforcing wall 105 cavity
27 outer end of the pipe
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