Foundation for a tower for a wind power plant, a transmission system or an overhead line

Abstract

The invention relates to a foundation for a tower for a wind power plant, a transmission system, for example for mobile radio, or an overhead line, having at least two foundation levels (2, 3) arranged one above the other, wherein at least two foundation levels (2, 3) each have at least two prefabricated concrete elements (4, 5) arranged next to one another, the prefabricated concrete elements (4, 5) each having at least one base section (41, 51) and at least one connecting piece section (42, 52), which each have an underside (411, 511, 422, 522), the at least one base section having at least one opening for receiving a clamping member, which are arranged in such a way that openings of base sections (41, 51) arranged one above the other are aligned, and at least one offset section (43, 53) is provided between the base section (41, 51) and the connecting piece section (42, 52) of the at least two concrete elements (4, 5) of at least one foundation level (2, 3), so that the undersides (422, 522) of the connecting piece sections (42, 52) of the concrete elements (4, 5) of at least two foundation levels (2, 3) arranged one above the other can be arranged substantially at the same height.

Description

[0001] September 26, 2023

[0002] (Applicant) praeziton UG (limited liability) Sachsenweg 112b 22455 Hamburg

[0003] (Title)

[0004] Foundation for a tower for a wind turbine, a transmitter or an overhead power line

[0005] ( Description )

[0006] (Technical field)

[0007] The invention relates to a foundation for a tower for a wind turbine, a transmitter, for example for mobile communications or an overhead power line.

[0008] ( State of the art )

[0009] Such foundations are essentially constructed as in-situ concrete foundations. For this, a pit is excavated at the construction site and lined with a leveling layer. The formwork and reinforcement are then erected, and the entire structure is filled with concrete on site. This results in a flat, flat structure, possibly with a base; see, for example, US 20160369520 Al or WO 2008 / 036934 A2. In addition to the transportation costs for delivering the concrete, formwork, and reinforcement, this process is very labor-intensive on site. Quality assurance is also complex and, depending on the weather, can be problematic. Furthermore, dismantling after the end of the wind turbine's service life is expensive and very time-consuming. This is especially true for concrete wind turbine towers, which ideally have a diameter-to-height ratio of approximately 1:10, meaning diameters of 8 to 15 meters are not uncommon.Foundations for such towers are currently constructed using cast-in-place concrete. Furthermore, areas must be provided where the tower's prestressing elements can be attached to the foundation and prestressed. Prestressing is carried out using specialized equipment that must be positioned within the prestressing zones. As abutments for prestressing and for attaching the prestressing elements (strands / cables), complex cantilever structures are typically incorporated within the foundation, beneath which the equipment is then positioned. These structures are complex and could be improved.

[0010] Furthermore, there is a fundamental need to construct such foundations from prefabricated elements, which could reduce or eliminate the aforementioned problems. In principle, it is advantageous that prefabrication allows the components to be produced in a standardized manner under defined conditions. It also reduces the amount of work required on site. Various approaches for this have been described in the prior art.

[0011] For example, WO 2008 / 036934 A2 shows a combination of prefabricated elements and classic formwork / reinforcement construction. This only marginally reduces the aforementioned disadvantages.

[0012] Further approaches for manufacturing foundations for wind turbines from prefabricated components are shown in the prior art as follows:

[0013] EP 1 058 787 Bl discloses a foundation for a wind turbine for the construction of offshore wind turbines that are transported fully pre-assembled – i.e., including the foundation – and placed on the seabed in one piece at the installation site. The foundation comprises 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 with a trapezoidal shape, on which the base section is vertically mounted at its inner end and has vertical openings. The planar base sections are connected to each other by means of tongue-and-groove joints. The base section and the planar base section are connected by a diagonal brace for stiffening. The circular segments of the base section also have vertical openings.Connecting cables / anchor rods are inserted into the passages. If the foundation components are made of concrete, a flat steel abutment ring is provided below the base elements in the area of ​​the vertical passages. The foundation is assembled using the connecting cables / anchor rods, and the wind turbine is attached to the foundation. Additionally, horizontal passages are provided in the base elements and diagonal braces, in which connecting cables / anchor rods are also arranged to horizontally prestress the foundation elements. Only through this horizontal prestressing is the foundation made load-bearing. Thus, EP 1 058 787 Bl discloses a foundation made of individual prefabricated concrete components, comprising a surface section and a base section, wherein at least these two sections are connected vertically and horizontally.

[0014] The disadvantage here is that considerable costs and considerable effort are required to connect the elements and to create the statically load-bearing foundation.

[0015] EP 1 074 663 A discloses a foundation for a wind turbine with a central body serving as a base, to which laterally extending, star-shaped ribs / projections / beams are bolted. The ribs and central body are bolted together horizontally on site. The components are prefabricated, including those made of concrete, and are delivered to the construction site by truck, positioned by crane, and connected horizontally on site via flanges and bolts. Anchors are also required on the outside of the ribs to ensure sufficient load transfer.

[0016] A disadvantage here is that significant costs and considerable labor are required to connect the elements and create a load-bearing foundation. Furthermore, additional anchors are necessary.

[0017] WO 2004 / 101898 A2 discloses a foundation for a wind turbine made of prefabricated concrete components, wherein either a central body is provided to which surface bodies are horizontally screwed, or the foundation consists exclusively of components that have both a flat section and a base-like section, which are then horizontally connected to each other by means of screwing against flanges.

[0018] The disadvantage here is that considerable costs and considerable effort are required to connect the elements and to create the statically load-bearing foundation.

[0019] EP 2 182 201 Al discloses two different foundations for a wind turbine. In both cases, a foundation is constructed from prefabricated concrete elements after delivery to the site. Both comprise a flat section and a plinth-like section. In variant 1, a central body is provided. The ribs / surface elements are attached to this. When assembled, the ribs form a polygonal body. The central body has a projection that is encompassed by a corresponding recess on the ribs. The ribs are additionally secured to the central body by means of a lashing ring. Anchor rods for mounting the tower are provided on the surface elements. In the second variant, the ribs have horizontally projecting anchor elements that, when assembled, extend radially towards the center of the foundation. Plates are provided above and below the anchors.The cast-in-place concrete is poured into the resulting cavity to connect the anchors and form a central body. Both variants simplify the horizontal connection. However, both the ribs and the central body have dimensions and masses that complicate transport.

[0020] 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, each with a base section at its inner end on which the wind turbine tower is mounted. The ribs extend radially outwards. In another embodiment, the sections between the ribs are filled with plate elements bolted to the ribs with flanges to form a slab. A steel sleeve is provided centrally instead of a central body; this sleeve is connected to reinforcements provided inside the ribs and to reinforcing beams located in the inner cavity. The ribs have a base plate on which a diagonal reinforcing element and the base section are integrally mounted. The base sections are connected horizontally to each other via tongue-and-groove joints.Furthermore, the base sections have horizontal openings in which tensioning elements are provided for horizontally connecting the base sections. Anchor rods for connecting the tower to the foundation are also cast into the base sections. External ground anchors are also disclosed. WO 2018 / 055444 discloses a foundation for a wind turbine with a circular or polygonal base body for supporting a wind turbine tower and several ribs projecting radially outwards from the base body, wherein the base body is divided vertically into a base ring section and an adapter ring section, the base ring section being subdivided into several circumferential sections and consisting of precast concrete elements, and the adapter ring section also consisting of precast concrete elements.

[0021] The disadvantage here is that considerable costs and considerable effort are required to connect the elements and to create the statically load-bearing foundation.

[0022] WO 2019 / 115622 Al and WO 2019 / 201714 A2 disclose the first successful foundations for wind turbines made of precast concrete elements, one for a steel tower and the other for a concrete tower. The foundations have two sections. Ribbed elements are provided, each with a central section upon which a base section is placed. The wind turbine tower is then positioned on the base section. The base section consists of individual segments that are connected to one another. Tensioning elements, located in openings in the central section and in the elements of the base section, brace the ribbed elements and the base elements together. Further development of these foundations has yielded surprising and particularly efficient improvements in the base area. However, it has been shown that manufacturing tolerances must be very tight to create a functional foundation.

[0023] WO 2021 / 064190 Al discloses a foundation in which prefabricated rib elements with an anchor cage and further reinforcement are cast on site using cast-in-place concrete and formwork to form a foundation.

[0024] (Task )

[0025] The object of the invention is therefore to overcome the aforementioned disadvantages and to make foundations for wind turbines, in particular for wind turbines with steel towers, more economical using prefabricated elements.

[0026] (Description of the invention)

[0027] The problem according to the invention is solved by a foundation for a tower for a wind turbine, a transmitter, for example for mobile communications or an overhead power line, with at least two foundation levels arranged one above the other, wherein at least two foundation levels each have at least two prefabricated concrete elements arranged side by side, wherein the prefabricated concrete elements each have at least one base section and at least one web section, each having a bottom surface, wherein the at least one base section has at least one opening for receiving a tendon, which are arranged such that the openings of the base sections arranged one above the other are aligned, wherein at least one offset section is provided between the base section and the web section of the at least two concrete elements of at least one foundation level.so that the undersides of the web sections of the concrete elements of at least two superimposed foundation levels can be arranged essentially at the same height.

[0028] It has been shown that by constructing the concrete elements and arranging them in individual levels, the number of different concrete elements required can be reduced. Furthermore, this construction allows for easier transport of the elements.

[0029] Another aspect of the invention provides for exactly two foundation levels. It has surprisingly been found that in this case, the manufacturing tolerance of the concrete elements, particularly in the vertical direction (Z-direction), can be significantly reduced. This reduces manufacturing costs and assembly effort.

[0030] A further aspect of the invention provides that the concrete elements of at least two superimposed foundation levels each have an offset element. This allows the height level of the undersides of the web sections to be easily adjusted.

[0031] Another teaching of the invention provides that the base sections and the web sections of the concrete elements are directly connected at least on one foundation level.

[0032] A further aspect of the invention provides that at least one web section comprises at least one base element having a bottom surface and a web element. Alternatively, a structure that is at least partially cuboid is advantageous.

[0033] Another aspect of the invention provides that the offset section is aligned diagonally upwards or downwards with respect to the underside of the base section. This allows the height level of the undersides of the web sections to be easily adjusted.

[0034] Another teaching of the invention provides that the base sections of the concrete elements form a base of the foundation on which the tower can be arranged, wherein the base is circular or polygonal.

[0035] Another teaching of the invention provides that the tension member is an anchor rod of an anchor cage.

[0036] Furthermore, it is advantageous that at least two ring-shaped abutments, preferably in the form of at least one abutment ring, are provided against which the tendon acts, with at least one abutment being arranged on the top side of the base and at least one abutment being arranged on the bottom side of the base. This provides, in a simple manner, the necessary load-bearing abutment for the tendons and the prestressing applied via them.

[0037] A further aspect of the invention provides that the base sections of the at least two adjacent concrete elements have a joint between them, and that the base sections of two superimposed concrete elements of two superimposed foundation levels are offset from one another, so that the joints between the base elements of one foundation level and the foundation level above it are not aligned. This results in a stable and easy-to-assemble foundation structure.

[0038] A further aspect of the invention is that the base sections of a foundation level do not touch each other in the joints between the base sections. This results in a stable and easy-to-assemble foundation structure.

[0039] (Description of the drawings)

[0040] The invention is explained in more detail below with reference to exemplary embodiments in conjunction with a drawing. The drawing shows:

[0041] Fig. 1 shows a side view of a first embodiment of a foundation according to the invention.

[0042] Fig. 2 is a top view of Fig. 1.

[0043] Fig. 3a shows a top view of a first invention.

[0044] Concrete element for Fig. 1 ,

[0045] Fig. 3b is a side view of Fig. 3a.

[0046] Fig. 3c is a side view from the outside of Fig. 3a, Fig. 3d is a spatial view of Fig. 3a.

[0047] Fig. 4a is a top view of a second apparatus according to the invention.

[0048] Concrete element as shown in Fig. 1,

[0049] Fig. 4b is a side view of Fig. 4a,

[0050] Fig. 4c shows a side view from the outside compared to Fig. 4a.

[0051] Fig. 4d is a spatial view of Fig. 4a,

[0052] Fig. 5 shows a side view of a second embodiment of a foundation according to the invention.

[0053] Fig. 6 is a top view of Fig. 5,

[0054] Fig. 7a is a top view of a first apparatus according to the invention.

[0055] Concrete element for Fig. 5,

[0056] Fig. 7b is a side view of Fig. 7a,

[0057] Fig. 8a shows a top view of a second apparatus according to the invention.

[0058] Concrete element for Fig. 5, and

[0059] Fig. 8b is a side view of Fig. 8a.

[0060] (Preferred embodiments of the invention)

[0061] Figures 1 to 4d show a first embodiment of a foundation 1 according to the invention with a first upper foundation level 2 and a second lower foundation level 3. In alternative embodiments, further levels are possible.

[0062] Figure 1 shows an assembled foundation of the first embodiment without a base, etc. Figure 2 shows an assembled foundation without a base, etc., in a top view. The first upper foundation level 2 is formed from several concrete elements 4, preferably shown here in Figures 4a to 4d.

[0063] The second lower foundation level 3 is formed from several concrete elements 5, which is preferably shown here in figures 3a to 3d.

[0064] The upper concrete element 4 has a base section 41 and a web section 42, which are connected to each other via an offset section 43. The base section 41 has a bottom surface 411 and a top surface 412, as well as an outer surface 413 and an inner surface 414.

[0065] The lower concrete element 5 has a base section 51 and a web section 52, which are directly connected to each other. The base section 51 has a bottom surface 511 and a top surface 512, as well as an outside surface 513 and an inside surface 514.

[0066] The base sections 41, 51 preferably have a ring segment shape, which, in the assembled state of the foundation 1, may, together with base sections of concrete elements not shown, form a ring-shaped base 6 of further foundation levels not shown. This base can also be polygonal if the base section 41, 51 has a corresponding shape. The base 6 itself preferably has a recess 8 in its center.

[0067] The tower (not shown) is arranged on a top surface 61 of the base 6 and connected to the foundation 1 by means of an anchor cage (not shown) or other connecting means (not shown).

[0068] The web section 42 of the upper concrete element 4 and / or the web section 52 of the lower concrete element 5, for example, comprise a base element 421, 521 having a bottom surface 422, 522, and a web element 423, 523 arranged on the base element 421, 521, preferably perpendicularly. Alternatively, the web section 42, 52 can also be a cuboid elongated concrete element or a similarly designed body. The offset section 43 of the upper concrete element 4 is arranged on the outer surface 413 of the base section 41. It is connected opposite the web section 42. The offset section 43 preferably has the same shape as the web 42.

[0069] The offset section 43 is generally oriented diagonally upwards or downwards, such that the underside 411 of the base section 41 and the underside 422 of the web section 42 have a height difference H. In the first embodiment of the concrete element 4, the offset element 43 is oriented diagonally downwards.

[0070] The height difference H is preferably designed such that the underside 422 of the web section 42 of the upper concrete element 4 and the underside 522 of the web section 52 of the lower concrete element 5 are at the same height or at the same level when the foundation 1 is installed.

[0071] In the first embodiment of the foundation 1, the web section 52 is preferably arranged on the base section 51 such that the underside 511 of the base section 51 and the underside 522 of the web section 52 are at the same level. However, it is also possible to arrange the web section 52 on the base section 51 such that the undersides 511 and 522 are not at the same level.

[0072] The bridge sections 42, 52 and possibly other not shown

[0073] The web sections together form a planar section 7 for transferring the loads acting on the tower. The undersides 422, 522, 411 of the web sections 42, 52 and the lower base sections 51 rest on the ground or on the leveling layer (not shown) of the construction site of the foundation 1.

[0074] The bridge sections 42, 52 are preferably arranged next to each other in the assembled state of the foundation 1 and do not overlap.

[0075] If more than two foundation levels are planned, the

[0076] Offset elements of the upper foundation levels are preferably arranged so that all undersides of the web sections are at the same height when the foundation is assembled in order to provide the most effective planar section 7.

[0077] In the base sections 41, 51, at least one opening (not shown) is provided between the upper surface 412, 512 and the lower surface 411, 511, in which a connecting element (not shown), for example, an anchor rod of an anchor cage (not shown) or the like, is arranged. The connecting elements vertically brace the foundation planes in the base. Two or more openings may be provided, spaced concentrically apart, so that one or more circular openings are provided in the base 6. These openings are arranged according to the requirements of the foundation 1 for transferring the static and dynamic loads of the tower, particularly in the case of a wind turbine.

[0078] Advantageously, gaps 9 / spaces are provided between the base sections 41, 51 of the concrete elements 4, 5 of a foundation level 2, 3. A base section 41, 51 is arranged above and below each gap, respectively. If an opening leads into a gap 9, a bridging element (not shown) may need to be provided as an abutment for a tendon.

[0079] Figures 5 to 8b show a second embodiment of a foundation 1 according to the invention with a first upper foundation level 2 and a second lower foundation level 3. In alternative embodiments, further levels are possible.

[0080] Figure 5 shows an assembled foundation of the first embodiment without a base. Figure 6 shows an assembled foundation without a base, etc., in a top view.

[0081] The first upper foundation level 2 is formed from several concrete elements 4, which is preferably shown here in Figures 7a and 7b.

[0082] The second lower foundation level 3 is formed from several concrete elements 5, preferably shown in Figures 8a and 8b. The upper concrete element 4 has a base section 41 and a web section 42, which are connected to each other via an offset section 43. The base section 41 has a bottom surface 411 and a top surface 412, as well as an outer surface 413 and an inner surface 414.

[0083] The lower concrete element 5 has a base section 51 and a web section 52, which are connected to each other via an offset section 53. The base section 51 has a bottom surface 511 and a top surface 512, as well as an outside surface 513 and an inside surface 514.

[0084] The base sections 41, 51 preferably have a ring segment shape, which, in the assembled state of the foundation 1, may, together with base sections of concrete elements not shown, form a ring-shaped base 6 of further foundation levels not shown. This base can also be polygonal if the base section 41, 51 has a corresponding shape. The base 6 itself preferably has a recess 8 in its center.

[0085] The tower (not shown) is arranged on a top surface 61 of the base 6 and connected to the foundation 1 by means of an anchor cage (not shown) or other connecting means (not shown).

[0086] The web section 42 of the upper concrete element 4 and / or the web section 52 of the lower concrete element 5, for example, comprise a base element 421, 521 having a bottom surface 422, 522, and a web element 423, 523 arranged on the base element 421, 521, preferably perpendicularly. Alternatively, the web section 422, 52 can also be a cuboid elongated concrete element or a similarly designed body.

[0087] The offset section 43, 53 is arranged on the outer surface 413, 513 of the base section 41, 51. It is connected opposite the web section 42, 52. The offset section 43, 53 preferably has the same shape as the web 42. The offset section 43, 53 is oriented diagonally upwards or downwards, such that the underside 411, 511 of the base section 41, 51 and the underside 422, 522 of the web section 42, 52 have a height difference H, H'. In the second embodiment of the foundation 1, the offset element 43 of the upper concrete element 4 is directed downwards and the offset element 53 of the lower concrete element is directed upwards.

[0088] The height difference H is preferably designed such that the underside 422 of the web section 42 of the upper concrete element 4 and the underside 522 of the web section 52 of the lower concrete element 5 are at the same height or at the same level when the foundation 1 is installed.

[0089] The bridge sections 42, 52 and possibly other not shown

[0090] The web sections together form a planar section 7 for transferring the loads acting on the tower. The undersides 422, 522, 411 of the web sections 42, 52 and the lower base sections 51 rest on the ground or on the leveling layer (not shown) of the construction site of the foundation 1.

[0091] The bridge sections 42, 52 are preferably arranged next to each other in the assembled state of the foundation 1 and do not overlap.

[0092] If more than two foundation levels are provided, the offset elements must preferably be arranged so that all undersides of the web sections are at the same height when the foundation is installed in order to provide the most effective planar section 7.

[0093] In the base sections 41, 51, at least one opening (not shown) is provided between the upper surface 412, 512 and the lower surface 411, 511, in which a connecting element (not shown), for example a tendon, in particular an anchor rod (not shown) of an anchor cage (not shown) or the like, is arranged. The connecting elements vertically brace or prestress the foundation planes in the base. Two or more openings may be provided, spaced concentrically apart, so that one or more circular openings are provided in the base 6, which are arranged according to the requirements of the foundation 1 for transferring the static and dynamic loads of the tower, in particular in the case of a wind turbine.

[0094] Advantageously, gaps 9 / spaces are provided between the base sections 41, 51 of the concrete elements 4, 5 of a foundation level 2, 3. A base section 41, 51 is arranged above and below each gap, respectively. If an opening leads into a gap 8, a bridging element (not shown) may need to be provided as an abutment for a tendon.

[0095] (Reference symbol list)

[0096] 1 Foundation

[0097] 2 Upper foundation level

[0098] 3 Lower foundation level

[0099] 4 concrete elements

[0100] 5 concrete elements

[0101] 6 sockets

[0102] 7 Area section

[0103] 8 recess

[0104] 9 gap

[0105] 41, 51 Base section

[0106] 411, 511 bottom

[0107] 412, 512 Top side

[0108] 413, 513 Outside

[0109] 414, 514 Inside

[0110] 42, 52 Bridge section

[0111] 421, 521 Floor element

[0112] 422, 522 Underside

[0113] 423, 523 Bridge element

[0114] 43, 53 offset section

[0115] 61 Top

[0116] H, H' height difference

Claims

(Patent claims) 1. Foundation for a tower for a wind turbine, a transmitter, for example for mobile communications or an overhead power line, with at least two superimposed foundation levels (2, 3), wherein at least two foundation levels (2, 3) each have at least two adjacent prefabricated concrete elements (4, 5), wherein the prefabricated concrete elements (4, 5) each have at least one base section (41, 51) and at least one web section (42, 52), each having a bottom surface (411, 511, 422, 522), wherein the at least one base section has at least one opening for receiving a tendon, which are arranged such that the openings of superimposed base sections (41, 51) are aligned, wherein at least one offset section (43, 53) is provided between the base section (41, 51) and the web section (42, 52) of the at least two concrete elements (4, 5) of at least one foundation level (2, 3). is,so that the undersides (422, 522) of the web sections (42, 52) of the concrete elements (4, 5) of at least two superimposed foundation levels (2, 3) can be arranged essentially at the same height.

2. Foundation according to claim 1, characterized in that exactly two foundation levels (2, 3) are provided.

3. Foundation according to claim 1 or 2, characterized in that at least two superimposed foundation levels (2, 3) each have an offset element (43, 53) between the base section (41, 51) and the web section (42, 52) of the concrete elements (4, 5).

4. Foundation according to one of claims 1 to 3, characterized in that the base section (41, 51) and the web section (42, 52) of the concrete elements (4, 5) are directly connected to at least one foundation level (2, 3).

5. Foundation according to one of claims 1 to 4, characterized in that at least one web section (42, 52) comprises at least one base element (421, 521) , which has the underside (422, 522) and a web element (423, 523).

6. Foundation according to one of claims 1 to 5, characterized in that the offset section (42, 52) is oriented diagonally upwards or downwards with respect to the underside (411, 511) of the base section (41, 51).

7. Foundation according to one of claims 1 to 6, characterized in that the base sections (41, 51) of the concrete elements (4, 5) form a base (6) of the foundation (1) on which the tower can be arranged, wherein the base (6) is circular or polygonal.

8. Foundation according to one of claims 1 to 7, characterized in that the tension member is an anchor rod of an anchor cage.

9. Foundation according to one of claims 1 to 8, characterized in that the base sections (41, 51) of the at least two adjacent concrete elements (4, 5) have a joint (9') between them, and that the base sections (41, 51) of two superimposed concrete elements (4, 5) of two superimposed foundation levels (2, 3) are arranged offset from each other, so that the joints (9') between the base elements (41, 51) of one foundation level (2, 3) and the foundation level (2, 3) above it are not aligned.

10. Foundation according to one of claims 1 to 9, characterized in that the base sections (41, 51) of a foundation plane (2, 3) do not touch in the joints (9') between the base sections (41, 51).

Images