A kind of anti-floating pile wind turbine foundation

Abstract

The utility model provides an anti-floating pile wind turbine foundation, comprising a wind turbine foundation pedestal and a plurality of anti-floating piles uniformly inserted at the bottom of the wind turbine foundation pedestal, wherein an installation platform is arranged inside the wind turbine foundation pedestal, and a prestressed cable is arranged through the top of the wind turbine foundation pedestal and the installation platform; when the wind turbine unit and the foundation deadweight, and the comprehensive load generated by other external factors are insufficient to balance the buoyancy generated by the groundwater, the application utilizes the tensile force generated by the tensile strength of the anti-floating piles themselves, and the pull-out force generated by the friction between the anti-floating piles and the soil layer, to restrain the floating tendency of the wind turbine foundation pedestal, so as to achieve the anti-floating purpose; the application better solves the problem that the gravity foundation is too large due to resisting the buoyancy of groundwater, saves the amount of reinforced concrete, and has better economy.

Description

Technical Field

[0001] The utility model relates to the technical field of wind power plant engineering, in particular to an anti-floating pile wind turbine foundation. Background Art

[0002] In the design of wind turbine foundations in existing wind farm projects, as the capacity of single wind turbines continues to increase, the load on the upper part of the foundation increases accordingly. In order to meet the bearing capacity requirements, the size of the foundation also continues to increase.

[0003] In the foundation design of natural bearing layers with shallow groundwater levels, if a gravity foundation platform is used, in order to balance the buoyancy of groundwater on the foundation slab, the foundation is usually large in size, with a diameter of more than 27m, a single foundation concrete consumption of more than 1,200t, a foundation burial depth of more than 4m, and a large amount of excavation and backfill. At the same time, due to the shallow groundwater level, it is difficult to dewater during construction.

[0004] However, if cast-in-place pile wind turbine foundation is used, the bearing capacity of the natural foundation cannot be well exerted and utilized, and the compressive bearing capacity of the cast-in-place piles cannot be fully exerted, resulting in waste of materials such as steel bars and concrete, and increased costs. Utility Model Content

[0005] In view of the problems existing in the prior art, the utility model provides an anti-floating pile fan foundation to solve the technical problems in the existing related technology: the fan foundation cannot provide reliable support in the presence of groundwater, and the use of a larger volume of fan foundation leads to higher costs.

[0006] The utility model is realized by the following technical solutions:

[0007] A wind turbine foundation with anti-floating piles comprises a wind turbine foundation pedestal and a plurality of anti-floating piles, and the plurality of anti-floating piles are evenly inserted into the bottom of the wind turbine foundation pedestal, an installation platform is arranged inside the wind turbine foundation pedestal, and a prestressed cable is arranged between the top of the wind turbine foundation pedestal and the installation platform.

[0008] Furthermore, the fan foundation support is a conical boss structure, the area below the ground is the large end, and the area above the ground is the small end.

[0009] Furthermore, the anti-floating piles are in a circular array and inserted into the bottom of the wind turbine foundation pedestal.

[0010] Furthermore, the circular arrays composed of the anti-floating piles are at least two groups, and the two groups of circular arrays are coaxially arranged.

[0011] Furthermore, the anti-floating pile includes an anti-floating anchor rod, and the anti-floating anchor rod is externally wrapped with grouting material.

[0012] Furthermore, the anti-floating anchor rod comprises a plurality of threaded steel bars connected to each other, and a centering bracket evenly spaced on the anti-floating anchor rod in the extension direction.

[0013] Furthermore, the centering bracket is obliquely provided with a plurality of positioning branches, and the plurality of positioning branches include at least two positioning branches that are symmetrical along the axis of the anti-floating anchor rod.

[0014] Furthermore, the threaded steel bars located at the top of the anti-floating anchor rod are distributed in a scattered manner.

[0015] Furthermore, the installation platform is coaxially arranged with the wind turbine foundation pedestal, and an annular limiting boss is arranged at the top of the installation platform along the radial direction of the wind turbine foundation pedestal, and a prestressed cable is penetrated through the annular limiting boss.

[0016] Furthermore, a cover plate is provided on the top of the installation platform.

[0017] Compared with the prior art, the utility model has the following beneficial technical effects:

[0018] The utility model provides an anti-floating pile wind turbine foundation, comprising a wind turbine foundation pedestal and a plurality of anti-floating piles uniformly inserted at the bottom of the wind turbine foundation pedestal, wherein an installation platform is arranged inside the wind turbine foundation pedestal, and a prestressed cable is arranged between the top of the wind turbine foundation pedestal and the installation platform; when the wind turbine unit and the foundation deadweight, and the comprehensive load generated by other external factors are insufficient to balance the buoyancy generated by the groundwater, the application utilizes the tensile force generated by the tensile strength of the anti-floating piles themselves, and the pull-out force generated by the friction between the anti-floating piles and the soil layer, to restrain the floating tendency of the wind turbine foundation pedestal, so as to achieve the anti-floating purpose; the application better solves the problem that the gravity foundation is too large due to resisting the buoyancy of groundwater, saves the amount of reinforced concrete, and has good economy; compared with the cast-in-place pile foundation, the anti-floating pile wind turbine foundation of the application avoids the problem that the compressive strength of the cast-in-place piles cannot be fully exerted, saves materials, has good economy, and has the advantages of easy quality control, high construction efficiency, low cost, short construction period, etc.

[0019] Furthermore, in this embodiment, the anti-floating piles are inserted into the bottom of the wind turbine foundation pedestal in a circular array, which can evenly provide anti-pulling force to the bottom of the wind turbine foundation pedestal to prevent it from being partially tilted due to the influence of buoyancy.

[0020] Furthermore, in the present embodiment, the anti-floating pile comprises an anti-floating anchor rod, and the anti-floating anchor rod is externally wrapped with grouting material. The cooperation between the anti-floating pile and the grouting material can improve the structural strength of the anti-floating pile.

[0021] Furthermore, in this embodiment, the centering bracket is obliquely provided with a plurality of positioning branches, wherein the plurality of positioning branches include at least two positioning branches symmetrical along the axis of the anti-floating anchor rod, and the positioning branches are used to make the anti-floating anchor rod be located at the axis position of the anti-floating pile during the grouting process.

[0022] Furthermore, in the present embodiment, a cover plate is provided on the top of the installation platform, and the cover plate is used to isolate some dust and debris, etc., and at the same time facilitate the inspection and daily maintenance of the fan foundation pedestal by technical personnel in the field. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A schematic diagram of an anti-floating pile wind turbine foundation in an embodiment of the present disclosure is shown;

[0024] Figure 2 A schematic structural diagram of the bottom of the wind turbine foundation cap in an embodiment of the present disclosure is shown;

[0025] Figure 3 A cross-sectional view of an anti-floating pile in an embodiment of the present disclosure is shown;

[0026] Figure 4 A schematic structural diagram of an anti-floating anchor rod in an embodiment of the present disclosure is shown.

[0027] In the figure: 1. Wind turbine foundation pedestal; 2. Anti-floating piles; 3. Prestressed cables; 4. Installation platform; 6. Grouting material; 7. Anti-floating anchor rods; 8. Centering bracket; 9. Fixed steel bars; 10. Positioning branches. DETAILED DESCRIPTION

[0028] The present invention will be further described in detail below in conjunction with the accompanying drawings, which are intended to explain the present invention rather than to limit it.

[0029] In order to enable those skilled in the art to better understand the solution of the utility model, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is only a part of the embodiment of the utility model, not all of the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the utility model.

[0030] It should be noted that the terms "first", "second", etc. in the specification and claims of the utility model and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the utility model described here can be implemented in an order other than those illustrated or described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, products or devices.

[0031] Figure 1 An anti-floating pile wind turbine foundation in an embodiment of the present disclosure is shown, including a wind turbine foundation pedestal 1, and a plurality of anti-floating piles 2 evenly inserted into the bottom of the wind turbine foundation pedestal 1, an installation platform 4 is arranged inside the wind turbine foundation pedestal 1, and a prestressed cable 3 is arranged between the top of the wind turbine foundation pedestal 1 and the installation platform 4.

[0032] It should be noted that since the anti-floating pile fan foundation is located in a natural bearing layer with a shallow groundwater level, in some cases, the groundwater will produce a certain buoyancy on the anti-floating pile fan foundation. When the buoyancy is large, the anti-floating pile fan foundation may have problems such as slight tilt.

[0033] It should be further explained that, in the embodiment of the present disclosure, the prestressed cables 3 are used to reinforce and enhance the stability and bearing capacity of the wind turbine foundation. The prestressed cables 3 are tensioned and anchored inside the foundation to generate prestress, thereby enhancing the wind turbine foundation's anti-overturning and anti-slip capabilities, which helps to ensure that the wind turbine foundation can remain stable and prevent displacement or overturning when subjected to external forces such as wind and earthquakes; at the same time, the introduction of the prestressed cables 3 can increase the bearing capacity of the wind turbine foundation. Under the action of the prestressed cables 3, the stress distribution inside the foundation is more uniform, thereby improving the foundation's compressive, tensile and shearing capabilities, which helps to ensure that during normal operation of the wind turbine, the foundation can withstand the wind turbine's own weight, wind loads and possible other external loads.

[0034] Preferably, in the disclosed embodiment, the wind turbine foundation support 1 is a conical boss structure, the area below the ground is the large end, and the area above the ground is the small end.

[0035] Preferably, in the embodiments of the present disclosure, Figure 2 As shown, the anti-floating piles 2 are inserted into the bottom of the wind turbine foundation pedestal 1 in a circular array; further, the circular array composed of the anti-floating piles 2 is at least two groups, and the two groups of the circular arrays are coaxially arranged.

[0036] It should be noted that in the embodiment disclosed herein, the circular array composed of the anti-floating piles 2 is composed of two groups, including an inner circle circular array and an outer circle circular array. The number of anti-floating piles 2 included in the inner circle circular array and the outer circle circular array is calculated and determined based on factors such as the geological conditions on site, the wind turbine units carried, and the environmental weather conditions. The principle is to meet both the bearing capacity requirements of the upper load of the foundation and the installation requirements of the tower.

[0037] Preferably, in the embodiments of the present disclosure, Figure 3 and Figure 4 As shown, the anti-floating pile 2 includes an anti-floating anchor rod 7, and the anti-floating anchor rod 7 is wrapped with a grouting material 6 on the outside. It should be noted that the surface of the grouting material 6 wrapped on the outside of the anti-floating anchor rod 7 has a certain roughness, which is used to form a certain friction with the ground to overcome the buoyancy of groundwater.

[0038] The grouting material 6 is made of concrete, which has the advantages of good self-flowability, high strength, slight expansion and no shrinkage, small strength change in high temperature or severe cold areas, and no corrosion damage to steel bars.

[0039] Furthermore, the anti-floating anchor rod 7 comprises a plurality of threaded steel bars connected to each other, and a centering bracket 8 evenly spaced and arranged on the anti-floating anchor rod 7 in the extension direction;

[0040] Specifically, in the disclosed embodiment, the same fixed steel bars 9 are welded at intervals between the plurality of interconnected threaded steel bars, the length of the fixed steel bars 9 is 50 mm, and a fixed steel bar 9 is welded at intervals of 1.5 m between the plurality of interconnected threaded steel bars, so as to improve the structural strength between the threaded steel bars. At the same time, by welding the fixed steel bars 9 at intervals, the grouting material 6 can be filled between the threaded steel bars, so that the connection between the threaded steel bars and the grouting material 6 is closer and tighter.

[0041] Furthermore, the centering bracket 8 is obliquely provided with a plurality of positioning branches 10, and the plurality of positioning branches 10 include at least two positioning branches 10 which are symmetrical along the axis of the anti-floating anchor 7; it should be noted that, in the embodiment disclosed herein, the positioning branch 10 is at an angle of 45° with the anti-floating anchor 7, and its function is to make the anti-floating anchor 7 be located at the axis position of the anti-floating pile 2 during the grouting process.

[0042] Furthermore, the threaded steel bars at the top of the anti-floating anchor 7 are distributed in a scattered manner. It should be noted that the threaded steel bars at the top of the anti-floating anchor 7 are correspondingly arranged at the bottom of the wind turbine foundation pedestal 1. Therefore, the threaded steel bars at the top of the anti-floating anchor 7 need to have a stronger connection strength with the grouting material 6.

[0043] Preferably, in the disclosed embodiment, the installation platform 4 is coaxially arranged with the wind turbine foundation support 1, and an annular limiting boss is arranged at the top of the installation platform 4 along the radial direction of the wind turbine foundation support 1, and the annular limiting boss is penetrated by a prestressed cable 3;

[0044] It should be noted that, in the embodiment of the present disclosure, the installation platform 4 is a circular cavity structure, a ring-shaped limiting boss is arranged on the top, and the bottom is spaced apart from the anti-floating pile 2.

[0045] Preferably, in the disclosed embodiment, a cover plate 5 is provided on the top of the installation platform 4, and the cover plate 5 is used to isolate some dust and debris, etc., and at the same time facilitate the technical personnel in the field to inspect and perform daily maintenance on the fan foundation pedestal 1.

[0046] This embodiment provides a construction step of an anti-floating pile wind turbine foundation, including:

[0047] (1) The production of the anti-floating anchor rod 7 is as follows: the cutting length of the anchor rod threaded steel bar is determined according to the design, and three threaded steel bars are welded through the fixing steel bar 9 to form the anti-floating anchor rod 7. Then, the centering bracket 8 is evenly arranged along the length direction of the anti-floating anchor rod 7 and fixed by welding. The high-strength steel bar centering bracket 8 should be smoothly produced and firmly welded.

[0048] (2) Anti-floating anchor hole drilling construction: The anti-floating anchor holes are drilled by mechanical drilling rigs and dry drilling operations are adopted. During the construction process, the drill rod should be kept perpendicular to the ground. The diameter and depth of the anchor hole should be checked in time during drilling to ensure that the hole diameter is not less than the designed hole diameter of 4 mm.

[0049] (3) Lower the anti-floating anchor rod 7 and use a crane to lift the anti-floating anchor rod 7 into the anti-floating anchor rod hole. During this process, the anti-floating anchor rod 7 should be prevented from twisting and bending, and the top elevation should be measured in time to reach the design elevation.

[0050] (4) Pouring grouting material 6, wherein the grouting material 6 is made of concrete, and the concrete is poured using a grouting pipe. The concrete body is fine stone concrete with a designed compressive strength of not less than 30 MPa.

[0051] (5) Maintenance and inspection of the anti-floating anchor rod 7. The maintenance period of the anti-floating anchor rod 7 after construction is 15 days. During the maintenance period, it is strictly forbidden to touch the exposed anchor head steel bar with external force. After the maintenance period, the anchor rod pulling and acceptance should be carried out in time. Only after the acceptance is qualified can the foundation pedestal construction be carried out. The pedestal construction needs to ensure the reliable connection between the anchor rod and the foundation steel bar.

[0052] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the utility model.

Claims

1. An anti-floating pile wind turbine foundation, characterized in that: The invention comprises a wind turbine foundation support platform (1), and a plurality of anti-floating piles (2) uniformly inserted into the bottom of the wind turbine foundation support platform (1), an installation platform (4) is arranged inside the wind turbine foundation support platform (1), and a prestressed cable (3) is arranged between the top of the wind turbine foundation support platform (1) and the installation platform (4).

2. The anti-floating pile wind turbine foundation according to claim 1, characterized in that: The fan foundation support (1) is a conical boss structure, the area below the ground is the large end, and the area above the ground is the small end.

3. The anti-floating pile wind turbine foundation according to claim 1, characterized in that: The anti-floating piles (2) are inserted into the bottom of the wind turbine foundation support platform (1) in a circular array.

4. The anti-floating pile wind turbine foundation according to claim 3, characterized in that: The circular arrays formed by the anti-floating piles (2) are at least two groups, and the two groups of circular arrays are coaxially arranged.

5. The anti-floating pile wind turbine foundation according to claim 1, characterized in that: The anti-floating pile (2) comprises an anti-floating anchor rod (7), and the anti-floating anchor rod (7) is externally wrapped with grouting material (6).

6. The anti-floating pile wind turbine foundation according to claim 5, characterized in that: The anti-floating anchor rod (7) comprises a plurality of threaded steel bars connected to each other, and a centering bracket (8) which is evenly spaced and arranged on the anti-floating anchor rod (7) in the extension direction.

7. The anti-floating pile wind turbine foundation according to claim 6, characterized in that: The centering bracket (8) is obliquely provided with a plurality of positioning branches (10), and the plurality of positioning branches (10) include at least two positioning branches (10) that are symmetrical along the axis of the anti-floating anchor rod (7).

8. The anti-floating pile wind turbine foundation according to claim 6, characterized in that: The threaded steel bars located at the top of the anti-floating anchor rod (7) are distributed in a scattered manner.

9. The anti-floating pile wind turbine foundation according to claim 1, characterized in that: The installation platform (4) is coaxially arranged with the fan foundation support platform (1), and an annular limiting boss is arranged at the top of the installation platform (4) along the radial direction of the fan foundation support platform (1), and a prestressed cable (3) is arranged through the annular limiting boss.

10. The anti-floating pile wind turbine foundation according to claim 1, characterized in that: A cover plate (5) is arranged on the top of the installation platform (4).

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