Fan foundation with variable cross-section piles and wind generating set

Abstract

The utility model belongs to the technical field of wind power fan foundations, and provides a fan foundation with variable cross-section piles and a wind generating set, which comprise a gravity type extended foundation and a plurality of variable cross-section pile foundations arranged on the gravity type extended foundation, the variable cross-section pile foundation comprises a plurality of pile bodies which are connected with one another and have different diameters; the diameters of the multiple pile bodies are distributed from large to small in the direction close to the gravity type extended foundation to the direction away from the gravity type extended foundation. The bending resistance is improved on the basis that the bearing capacity is guaranteed through the arrangement of the multiple variable cross-section pile foundations, and the requirements for the thickness, the bottom area and other sizes of the gravity type extended foundation are reduced through the arrangement of the variable cross-section piles; the variable cross-section pile foundation comprises the multiple pile bodies which are connected with one another and have different diameters, the diameters of the multiple pile bodies are distributed from large to small in the direction towards the ground during construction, the requirement for ground drilling construction can be lowered, and construction in areas with hard geology such as mountainous regions is facilitated.

Description

Technical Field

[0001] The utility model belongs to the technical field of wind power turbine foundations, and particularly relates to a wind turbine foundation with variable cross-section piles and a wind power generating set. Background Art

[0002] The gravity spread foundation is a common type of wind turbine foundation, which is characterized by enhancing stability and bearing capacity by increasing the area at the bottom of the foundation. This foundation mainly relies on its own weight and the extensive contact area of the extended part to resist various forces generated during the operation of the wind turbine.

[0003] The inventor found that although the current gravity spread wind turbine foundation performs well in terms of compressive capacity and can effectively resist the vertical load from the operation of the wind turbine, it performs poorly in terms of bending resistance; it usually adopts a wide and thick concrete slab with a large bottom area to provide sufficient stability and bearing capacity, resulting in poor economy and certain requirements for the area of the construction site; and the development of wind turbine generators in special areas such as mountains is relatively fast. The method of simply increasing the lower foundation on the original gravity spread wind turbine foundation to improve stability and bearing capacity is not easy to construct in areas with hard geology such as mountains. Summary of the Utility Model

[0004] In order to solve the above problems, the utility model provides a wind turbine foundation with variable cross-section piles and a wind power generating set. The utility model sets multiple variable cross-section pile foundations, which improves the bending resistance while ensuring the bearing capacity. The setting of the variable cross-section piles reduces the requirements for the dimensions such as the thickness and bottom area of the gravity spread foundation, and can reduce the actual size of the gravity spread foundation; multiple pile bodies that are interconnected and have different diameters can reduce the requirements for ground drilling construction and are beneficial to construction in areas with hard geology such as mountains.

[0005] According to some embodiments, the first solution of the utility model provides a wind turbine foundation with variable cross-section piles, and adopts the following technical solution:

[0006] A wind turbine foundation with variable cross-section piles includes a gravity spread foundation and multiple variable cross-section pile foundations arranged on the gravity spread foundation;

[0007] The variable cross-section pile foundation includes multiple interconnected pile bodies with different diameters; the diameters of the multiple pile bodies are distributed from large to small along the direction from near the gravity spread foundation to far from the gravity spread foundation.

[0008] Furthermore, multiple variable cross-section pile foundations are evenly distributed in the circumferential direction of the gravity spread foundation.

[0009] Furthermore, the variable cross-section pile foundation is connected to the gravity spread foundation through anchor bars.

[0010] Furthermore, a plurality of anchor bars are provided between the variable cross-section pile foundation and the gravity spread foundation.

[0011] Furthermore, an anchor plate is provided between the variable cross-section pile foundation and the anchor bars.

[0012] Furthermore, a cushion layer is provided on the gravity spread foundation.

[0013] Furthermore, a plurality of bolt connection holes are provided on the gravity spread foundation.

[0014] Furthermore, the variable cross-section pile foundation includes a first pile body connected to the gravity spread foundation and a second pile body connected to the first pile body; the diameter of the first pile body is greater than the diameter of the second pile body.

[0015] Furthermore, anchor bars are provided between a plurality of pile bodies.

[0016] According to some embodiments, a second solution of the present utility model provides a wind turbine generator set, adopting the following technical solution:

[0017] A wind turbine generator set includes a wind turbine foundation with variable cross-section piles as described in the first aspect.

[0018] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0019] The present utility model provides a plurality of variable cross-section pile foundations on the gravity spread foundation. On the basis of ensuring the bearing capacity, the bending resistance is improved. Moreover, the setting of the variable cross-section piles reduces the requirements for the thickness and bottom area of the gravity spread foundation and other dimensions, and can reduce the actual size of the gravity spread foundation, improving the economy; the variable cross-section pile foundation includes a plurality of interconnected pile bodies with different diameters, and the diameters of the plurality of pile bodies are distributed from large to small in the direction towards the ground during construction, which can reduce the requirements for ground drilling construction and is beneficial to construction in mountainous areas and other areas with relatively hard geology. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The specification drawings constituting a part of the present utility model are used to provide a further understanding of the present utility model. The schematic embodiments of the present utility model and their descriptions are used to explain the present utility model and do not constitute an improper limitation to the present utility model.

[0021] Figure 1 is a schematic diagram of the basic structure of the present utility model;

[0022] Figure 2 is a top view of the foundation of the present utility model;

[0023] Figure 3It is a schematic diagram of the gravity-type spread foundation structure of the present utility model;

[0024] Figure 4 It is a schematic diagram of the stepped pile foundation structure of the present utility model;

[0025] Wherein: 1. Gravity-type spread foundation; 2. Stepped pile foundation; 201. First pile body; 202. Second pile body; 3. Anchor bar; 4. Cushion; 5. Anchor plate; 6. Bolt connection hole. Detailed implementation manners

[0026] The present utility model will be further described below in conjunction with the accompanying drawings and embodiments.

[0027] It should be noted that the following detailed descriptions are all illustrative and are intended to provide further explanations of the present utility model. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present utility model belongs.

[0028] Embodiment 1:

[0029] The fan foundation is an important part of the wind turbine generator set, and its design and construction are directly related to the safe operation and service life of the wind turbine unit. With the rapid development of the wind power industry, the design of the fan foundation has become increasingly complex. It has an important impact on the safe operation, seismic performance, fatigue life of the fan, and stability under special environments. Reasonable design and construction of the fan foundation are the prerequisite for ensuring the efficient, safe, and long-life operation of the fan.

[0030] The gravity-type spread foundation is a common type of fan foundation, and its characteristic is to enhance the stability and bearing capacity by increasing the area of the bottom of the foundation. This foundation mainly relies on its own weight and the extensive contact area of the extended part to resist various forces generated during the operation of the fan. The construction is relatively simple, there is rich engineering experience, and the applicable range is wide. Because its design and construction methods have been verified by years of practice, the construction technology is mature, the construction period is short, and the requirements for construction equipment and technology are not high

[0031] However, although the gravity-type spread foundation form performs well in terms of compressive capacity and can effectively resist the vertical load from the operation of the fan, it performs poorly in terms of bending resistance. It usually uses a wide and thick concrete slab with a large bottom area to provide sufficient stability and bearing capacity. Although this design performs well in resisting vertical pressure, it is not ideal in resisting horizontal forces and base moments. To resist the base moment received by the foundation, the size of the foundation slab is very large, and the economy is poor.

[0032] Based on the above problems, this embodiment provides a fan foundation with stepped piles, which increases the bending resistance of the fan foundation and reduces the amount of foundation materials; asFigure 1 As shown in the figure, the wind turbine foundation with variable cross-section piles includes a gravity spread foundation 1 and a plurality of variable cross-section pile foundations 2 arranged on the gravity spread foundation 1;

[0033] The variable cross-section pile foundation 2 includes a plurality of pile bodies that are interconnected and have different diameters; the diameters of the plurality of pile bodies are distributed from large to small in the direction away from the gravity spread foundation 1 towards the gravity spread foundation 1.

[0034] Specifically, by arranging a plurality of variable cross-section pile foundations 2 on the gravity spread foundation 1, the flexural capacity is improved on the basis of ensuring the bearing capacity. Moreover, the setting of the variable cross-section piles reduces the requirements for the dimensions such as the thickness and bottom area of the gravity spread foundation 1, which can reduce the actual size of the gravity spread foundation 1 and improve the economy; the variable cross-section pile foundation 2 includes a plurality of pile bodies that are interconnected and have different diameters, and the diameters of the plurality of pile bodies are distributed from large to small in the direction towards the ground during construction, which can reduce the requirements for ground drilling construction and is beneficial to construction in areas with relatively hard geology such as mountains.

[0035] As Figure 2 shown, optionally, a plurality of variable cross-section pile foundations 2 are evenly distributed circumferentially on the gravity spread foundation 1, which improves the flexural capacity of the foundation in all directions and enhances the fixing stability of the wind turbine generator set.

[0036] As Figure 1 shown, the variable cross-section pile foundation 2 is connected to the gravity spread foundation 1 through anchor bars 3; optionally, multiple anchor bars 3 are arranged between the variable cross-section pile foundation 2 and the gravity spread foundation 1. Ensure that the position and length of the anchor bars 3 meet the design requirements. Optionally, the anchor bars 3 are made of high-strength steel bars and filled with high-strength grouting material to ensure the tight connection between the anchor bars 3 and the pile bodies.

[0037] As Figure 1 shown, an anchor plate 5 is arranged between the variable cross-section pile foundation 2 and the anchor bars 3; optionally, a plurality of through holes are opened on the anchor plate 5, threads are opened at the ends of the anchor bars 3, and after the anchor bars 3 pass through the through holes on the anchor plate 5, nuts are arranged on the threads for reinforcement. It can be understood that the diameter of the through holes on the anchor plate 5 is larger than the diameter of the anchor bars 3 and smaller than the diameter of the nuts.

[0038] As Figure 1 and Figure 3 shown, a cushion layer 4 is arranged on the gravity spread foundation 1 to ensure the flatness and stability of the bottom plate. As Figure 1 and Figure 2 shown, a plurality of bolt connection holes 6 are arranged on the gravity spread foundation 1 for cooperating with bolts to connect the wind turbine tower barrel.

[0039] AsFigure 4 As shown, the variable cross-section pile foundation 2 includes a first pile body 201 connected to the gravity spread foundation 1 and a second pile body 202 connected to the first pile body 201; the diameter of the first pile body 201 is greater than that of the second pile body 202. Of course, the number of pile bodies in the variable cross-section pile foundation 2 can be selected according to the actual situation.

[0040] One of the construction processes or working principles of this embodiment can be:

[0041] According to the geological exploration results and requirements such as the wind turbine load, determine the foundation design scheme, including the number, position, length, and cross-sectional dimensions of the variable cross-section pile foundation 2, as well as the dimensions of the gravity spread foundation 1 and the design of the extended part, and the configuration of the anchor bars, etc.

[0042] Drive the anchor bars 3 into the bottom of the variable cross-section pile foundation 2 and penetrate into the rock formation to ensure that the spacing and depth of the anchor bars 3 meet the design requirements. The length of the anchor bars 3 should ensure that they can be firmly embedded in the foundation soil layer.

[0043] Adopt appropriate pile driving or drilling techniques and construct according to the geological conditions and pile design requirements. For bored cast-in-place piles, carry out drilling, hole cleaning, and installation of the steel reinforcement cage, fix the anchor bars and the steel reinforcement cage of the smaller-diameter pile body part to ensure that the anchor bars 3 do not move during the concrete pouring process.

[0044] Reserve anchor bar holes for the larger-diameter pile body part, determine the position and number of the anchor bars 3 according to the design requirements, insert the anchor bars 3 into the reserved holes to ensure that the position and length of the anchor bars 3 meet the design requirements. Use high-strength steel bars and pour with high-strength grouting material to ensure the tight connection between the anchor bars and the pile body.

[0045] According to the design drawings, excavate the foundation pit of the gravity spread foundation 1 to ensure that the size and depth of the foundation pit meet the design requirements.

[0046] Fix the prestressed steel bars of the larger-diameter pile body part and the steel bar mesh of the gravity spread foundation 1 together to ensure that the anchor bars do not move during the concrete pouring process.

[0047] Pour the concrete into the formwork to ensure that the thickness and strength of the cushion 4 meet the design requirements. During the concrete pouring process, it is necessary to ensure that the position of the anchor bars 3 is correct and connected to the anchoring end of the variable cross-section pile foundation 2.

[0048] Anchore the prestressed anchor bars of the larger-diameter pile body part to the top of the gravity spread foundation 1 through the anchor plate 5 to ensure the stable and reliable connection between the gravity spread foundation 1 and the variable cross-section pile foundation 2 located at the bottom.

[0049] The wind turbine foundation with variable cross-section piles provided in this embodiment combines the advantages of gravity spread foundations and variable cross-section pile foundations. It can not only provide a large vertical bearing capacity, but also effectively resist horizontal loads and bending moments, improving the overall stability; it improves the flexural stiffness of the foundation and reduces the risk of deformation and damage under the action of horizontal forces and bending moments. The proposed wind turbine foundation with variable cross-section piles is applicable to various geological conditions, especially complex sites with low foundation bearing capacity. The loads are transmitted to deeper and more stable strata through the variable cross-section piles. Where large cross-sections are not required, the cross-section size is reduced, and the material cost is lowered. During the construction process, the design of the variable cross-section piles helps to reduce the impact on the surrounding environment during pile driving or drilling.

[0050] Embodiment 2:

[0051] This embodiment provides a wind power generation unit, including the wind turbine foundation with variable cross-section piles as described in Embodiment 1; it is connected to the wind turbine tower through the bolt connection holes 6 and bolts of the wind turbine foundation with variable cross-section piles. Other settings of the wind power generation unit can be achieved by conventional techniques and will not be elaborated here.

[0052] The above are only the preferred embodiments of the present utility model and are not used to limit the present utility model. For those skilled in the art, various modifications and changes can be made to the present utility model. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A wind turbine foundation with variable cross-section piles, characterized in that, It includes a gravity spread foundation and a plurality of stepped pile foundations arranged on the gravity spread foundation; The stepped pile foundation includes a plurality of interconnected piles with different diameters; the diameters of the plurality of piles are distributed from large to small along the direction from near the gravity spread foundation to far from the gravity spread foundation.

2. The wind turbine foundation with variable cross-section piles according to claim 1, characterized in that, A plurality of stepped pile foundations are evenly distributed circumferentially on the gravity spread foundation.

3. The wind turbine foundation with variable cross-section piles according to claim 1, characterized in that, The stepped pile foundation is connected to the gravity spread foundation through anchor bars.

4. The wind turbine foundation with variable cross-section piles according to claim 3, characterized in that A plurality of anchor bars are arranged between the stepped pile foundation and the gravity spread foundation.

5. The wind turbine foundation with variable cross-section piles according to claim 3, characterized in that, An anchor plate is arranged between the stepped pile foundation and the anchor bar.

6. The wind turbine foundation with variable cross-section piles according to claim 1, characterized in that, A cushion layer is arranged on the gravity spread foundation.

7. The wind turbine foundation with variable cross-section piles according to claim 1, characterized in that, A plurality of bolt connection holes are arranged on the gravity spread foundation.

8. The wind turbine foundation with variable cross-section piles according to claim 1, characterized in that, The stepped pile foundation includes a first pile connected to the gravity spread foundation and a second pile connected to the first pile; the diameter of the first pile is larger than that of the second pile.

9. The wind turbine foundation with variable cross-section piles according to claim 1, characterized in that, Anchor bars are arranged between the plurality of piles.

10. A wind turbine generator, characterized in that, It includes a wind turbine foundation with stepped piles according to any one of claims 1-9.

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