Foundation structure of fan foundation

Abstract

The utility model relates to a foundation structure of a fan foundation, and belongs to the technical field of wind power generation equipment. The structure comprises an earthwork standard room layer (1) and a plain concrete layer (3), the earthwork standard room layer (1) comprises earthwork standard rooms (11) and filler, the earthwork standard rooms (11) are laid on the bottom face of a foundation pit, and internal gaps of the earthwork standard rooms (11) are filled with the filler; the plain concrete layer (3) is arranged on the upper end face of the geocell layer (1). According to the structure, a structural body with strong lateral limitation and high rigidity is formed through the earthwork standard room (11), meanwhile, the plain concrete layer (3) has certain capacity of resisting environmental erosion, and the service life of the whole structure can be prolonged through the composite structural layer formed by combining the earthwork standard room layer (1) and the plain concrete layer (3). The problems that an existing soft soil layer foundation poor in mechanical property is long in construction period and high in cost are solved.

Description

Technical Field

[0001] The utility model relates to a wind turbine foundation structure and belongs to the technical field of wind power generation equipment. Background Art

[0002] Wind power projects often use traditional foundation treatment methods to treat the soft foundation of wind turbine foundations. However, when these methods are used to treat the wind turbine foundations in depth, the treatment scale of the soft foundation is large and the treatment cost is high. Even if the above methods are used to treat the soft soil foundation of the wind turbine foundation in a shallow layer, a large amount of unsuitable soil needs to be excavated and transported to the waste dump, and then backfilled with soil, sand, gravel, etc., and wind farms are often located in remote areas. Not only is the transportation volume large and the cost high, but the construction takes a long time and causes great damage to the environment. Utility Model Content

[0003] The technical problem to be solved by the utility model is that the existing soft soil foundation with poor mechanical properties has a long construction period, high cost and difficult cost control.

[0004] The technical solution adopted by the utility model to solve its technical problems is: a wind turbine foundation structure, including a geocell layer and a plain concrete layer, the geocell layer includes geocells and fillers, the geocells are laid on the bottom surface of the foundation pit, and the fillers are filled into the internal gaps of the geocells; the plain concrete layer is arranged on the upper end surface of the geocell layer.

[0005] Wherein, the geocell in the above structure is formed by splicing a number of blocks, and adjacent geocells are connected by snaps or U-shaped nails, and the geocells are fixed by a self-anchoring reinforcement mode.

[0006] Wherein, the geocell in the above structure is made of high-density polyethylene, and the size of the holes on the geocell is 10 to 15 cm.

[0007] Wherein, the filler in the above structure is gravel or soil with a particle size of ≤30 mm and less impurities.

[0008] Among them, in the above structure, a combination of static rolling and vibration rolling is used to compact the geocell layer so that a filler protective layer is formed on its upper end.

[0009] Furthermore, the geocell layer in the above structure is statically pressed 2 to 3 times so that the geocell is completely covered with fillers, and then vibrated and rolled.

[0010] Wherein, the upper end of the plain concrete layer in the above structure is provided with embedded parts and foundation concrete, and backfill soil is provided in the foundation pit outside the foundation concrete.

[0011] The beneficial effects of the present utility model are as follows: This structure actually relies on the actual on-site situation and locally sourced materials to lay the geocell layer. The finished HDPE geocell products are transported to the site, with a short construction period and controllable foundation treatment quality. During construction, it can be tensioned into a net shape and filled with loose materials such as soil, gravel, and concrete to form a structure with strong lateral restraint and high stiffness. The HDPE geocell has excellent corrosion resistance and is suitable for projects that interact with different soils and environments, especially in situations where corrosive substances may be involved. At the same time, the plain concrete layer also has a certain ability to resist environmental erosion. The composite structure layer formed by the combination of the geocell layer and the plain concrete layer can improve the service life of the overall structure. Moreover, HDPE is a lightweight material, which is convenient for handling and installation, helping to reduce the labor intensity of the project; and it has a relatively low cost, which helps to control costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic cross-sectional structure diagram of the present utility model.

[0013] Figure 2 For the present utility model Figure 1 An enlarged schematic diagram of the structure at I in the figure.

[0014] Figure 3 It is a schematic diagram of the structure of the geocell of the present utility model.

[0015] The markings in the figure are: 1 is the geocell layer, 11 is the geocell, 2 is the filler protection layer, 3 is the plain concrete layer, 4 is the foundation concrete, 5 is the embedded part, and 6 is the backfill soil. SPECIFIC EMBODIMENTS

[0016] The present utility model will be further described below with reference to the accompanying drawings.

[0017] As Figures 1 to 3As shown in the figure, a foundation structure for a fan foundation of the present utility model includes a geocell layer 1 and a plain concrete layer 3. The geocell layer 1 includes geocells 11 and fillers. The geocells 11 are laid on the bottom surface of the foundation pit, and the fillers are filled into the internal gaps of the geocells 11. The plain concrete layer 3 is arranged on the upper end surface of the geocell layer 1. Those skilled in the art can understand that this structure forms a structure with strong lateral restraint and large stiffness through the geocells 11. At the same time, the plain concrete layer 3 also has a certain ability to resist environmental erosion. The composite structure layer formed by the combination of the geocell layer 1 and the plain concrete layer 3 can improve the service life of the overall structure. Therefore, the geocells 11 are arranged in the foundation pit that has passed the foundation inspection and are fixed in the foundation pit, and the height of the geocells 11 should be determined according to the depth of the replaced soft soil layer and the bearing capacity of the underlying soil layer. The fillers are filled into the internal gaps of the geocells 11 and compacted to form the geocell layer 1. Then, formwork is installed on the surface of the geocell layer 1 to ensure that a regular foundation shape, that is, the plain concrete layer 3, can be formed during concrete pouring, and concrete is poured to ensure that the concrete evenly covers the geocell layer 1.

[0018] Preferably, in the above structure, the geocells 11 are formed by splicing several pieces, and adjacent geocells 11 are connected by buckles or U-shaped nails. The geocells 11 are fixed in a self-anchoring reinforcement mode. Those skilled in the art can understand that due to the large size of the foundation pit, for the convenience of handling the geocells 11, the preferred geocells 11 are formed by splicing several pieces. Actually, on the already accepted foundation pit, the geocells 11 are unfolded, straightened smoothly, laid flat tightly against the foundation pit, connected by buckles or U-shaped nails at the longitudinal and transverse intersections, and fixed in a self-anchoring reinforcement mode to ensure the overall force balance. The perforated geocells 11 can achieve the purpose of lateral drainage by perforating the cell walls.

[0019] Preferably, in the above structure, the geocell 11 is made of high-density polyethylene, and the hole size on the geocell 11 is 10 - 15 cm. Those skilled in the art can understand that in this structure, it is preferred that the geocell 11 is made of high-density polyethylene, that is, the material of the geocell 11 is selected as HDPE. It has excellent corrosion resistance, can resist the erosion of soil, water and chemical substances for a long time, maintain stable performance, has high tensile strength and compressive strength, can withstand large loads and stresses, and ensure the stability and safety of the foundation structure; it is lighter than traditional materials, convenient for transportation, handling and installation, reduces the construction difficulty and cost; has good anti-aging performance and long-term stability, has a long service life, and can operate continuously for many years; has high flexibility and bendability, can adapt to the deformation and distortion of the foundation, and maintain overall stability; is made of environmentally friendly materials, non-toxic and harmless, does not pollute the environment, and meets the requirements of sustainable development. For the convenience of filling and compressing the filler, it is preferred that the holes on the geocell 11 are 10 - 15 cm, and the holes here are the vertical hole sizes after the geocell 11 is laid and fixed in the foundation pit, which can be the diameter or the width of 10 - 15 cm.

[0020] Preferably, in the above structure, the filler is gravel or soil with a particle size ≤ 30 mm and less impurities. Those skilled in the art can understand that in actual use, a loader or a backhoe is used in cooperation with manual labor for paving, and a machine is used to backfill the filler into the firmly fixed geocell 11. During the backfilling process, the accumulated filler is evenly spread into the geocell 11 by manual labor at any time; and the filling material is gravel soil or the soil at the construction site. Gravel with a maximum particle size less than or equal to 30 mm and less impurities should be selected, or soil with low humidity and few impurities should be selected locally for filling; the principle of filler selection is to ensure controllable quality and fully consider and utilize on-site resources. This solution can not only save construction costs and shorten the construction period, but also have less impact on the environment, meeting the green theme of new energy wind power generation.

[0021] Preferably, in the above structure, the geocell layer 1 is compacted by a combination of static rolling and vibratory rolling to form a filler protection layer 2 at its upper end. Those skilled in the art can understand that during construction, the loose paving coefficient should be determined according to different fillers, and the height of the filler protection layer 2 should be reserved, and the height of the filler above the geocell should be comprehensively determined. The geocell layer 1 is compacted by a combination of static rolling and vibratory rolling to form a filler protection layer 2 at its upper end.

[0022] Preferably, in the above structure, the geocell layer 1 is statically pressed 2 to 3 times so that the geocell 11 is completely covered with the filler, and then vibratory compaction is carried out. Those skilled in the art can understand that, first, the static roller is used to fix the filler in the geocell 11, and static pressing 2 to 3 times ensures that the geocell 11 is completely covered with the filler; then vibratory compaction is used to further compact the filler. During the whole process, the stress condition of the geocell 11 needs to be observed at any time to prevent over-compaction from damaging the geocell 11; after the geocell is laid, the degree of compaction also needs to be measured to meet the design requirements.

[0023] Preferably, in the above structure, embedded parts 5 and foundation concrete 4 are arranged at the upper end of the plain concrete layer 3, and backfill soil 6 is arranged in the foundation pit outside the foundation concrete 4. Those skilled in the art can understand that since this structure is mainly used for fixing the fan base, actually, embedded parts 5 and foundation concrete 4 are arranged at the upper end of the plain concrete layer 3. The embedded parts 5 are fixed through the foundation concrete 4 and are cast integrally with the plain concrete layer 3, while backfill soil 6 is arranged in the foundation pit outside the foundation concrete 4.

[0024] The implementation plan of this structure is as follows:

[0025] 1. Foundation pit excavation

[0026] The foundation pit is excavated to the base elevation of the fan extended foundation, and the excavation line refers to Figure 1 , if the geocell 11 is directly arranged on the surface of the foundation pit, it will have a certain impact on the normal performance of the geocell 11, and the foundation pit needs to be treated first; the bottom of the pit is cleaned, the site is leveled and compacted; ensure that it meets the compaction degree and flatness requirements of the specification.

[0027] 2. Construction of geocell - plain concrete layer

[0028] 1) After the foundation pit is excavated, the foundation pit inspection work needs to be carried out according to the design requirements. The geocell 11 can be arranged only after the actual situation of the excavation area conforms to the design requirements; a 10 - 15 cm perforated geocell 11 is laid on the treated foundation pit, and the height of the geocell 11 should be determined according to the depth of the replaced soft soil layer and the bearing capacity of the underlying soil layer.

[0029] The material of the geocell 11 is selected as HDPE. On the already inspected foundation pit, the geocell 11 is unfolded, straightened and smoothed, laid flat against the foundation pit tightly, and the longitudinal and transverse intersections are connected with buckles or U - shaped nails and fixed in a self - anchoring reinforcement mode to ensure the overall balanced stress; the perforated geocell 11 can achieve the purpose of lateral drainage by perforating the cell wall.

[0030] 2) The loader or backhoe is used in cooperation with manual labor for spreading, and mechanical equipment is used to backfill the filler into the firmly fixed geocell 11. During the backfilling process, manual labor is used to evenly spread the accumulated filler into the geocell 11 at any time;

[0031] The filling material uses crushed stone soil or the soil at the construction site. Crushed stones with a maximum particle size less than or equal to 30 mm and less impurities should be selected, or the soil with low humidity and few impurities should be selected locally for filling. The principle of filler selection is to control the quality as the premise, and fully consider and utilize the on-site resources. This scheme can not only save the construction cost and shorten the construction period, but also has less impact on the environment, meeting the theme of green new energy wind power generation.

[0032] During construction, the loose paving coefficient should be determined according to different fillers, and the height of the filler protection layer 2 should be reserved, and the height of the filler above the geocell should be comprehensively determined.

[0033] 3) After backfilling is completed, compaction treatment is carried out on the geocell layer 1, using a combination of static rolling and vibratory rolling. First, use static rolling to fix the filler in the geocell 11, and static press 2 - 3 times to ensure that the geocell 11 is completely covered by the filler; then use vibratory rolling to further compact the filler. During the whole process, the stress condition of the geocell 11 needs to be observed at any time to prevent over-rolling from damaging the geocell 11; after the geocell is laid, the degree of compaction also needs to be measured to meet the design requirements.

[0034] 4) Install the formwork on the surface of the geocell layer 1 to ensure that a regular foundation shape can be formed during concrete pouring. Conduct concrete pouring to ensure that the concrete evenly covers the geocell layer 1, and control the pouring speed and slump to avoid the generation of bubbles and cracks;

[0035] Use a vibrator to vibrate the concrete to ensure the compactness of the concrete. Conduct surface treatment, which may include troweling, polishing or other decorative treatments.

[0036] Conduct appropriate curing on the newly poured concrete to ensure the gradual increase of its strength.

[0037] During the curing period, prevent the surface of the concrete from cracking, usually by covering with a wet cloth, spraying water, etc.

[0038] 5) Backfill the remaining space in the foundation pit.

Claims

1. A wind turbine foundation structure, characterized in that: The invention comprises a geocell layer (1) and a plain concrete layer (3), wherein the geocell layer (1) comprises a geocell (11) and a filler, wherein the geocell (11) is laid on the bottom surface of a foundation pit, and the filler is filled into the internal gap of the geocell (11); the plain concrete layer (3) is arranged on the upper end surface of the geocell layer (1); the geocell (11) is formed by splicing a plurality of blocks, and adjacent geocells (11) are connected by snaps or U-shaped nails, and the geocell (11) is fixed by a self-anchoring reinforcement mode; the geocell (11) is made of high-density polymer. The geocell (11) is made of polyethylene, and the size of the holes on the geocell (11) is 10 to 15 cm; the filler is crushed stone or soil with a particle size of ≤30 mm and less impurities; the geocell layer (1) is compacted by a combination of static rolling and vibration rolling to form a filler protection layer (2) on its upper end; the geocell layer (1) is statically pressed 2 to 3 times so that the geocell (11) is completely covered with the filler, and then vibrated and rolled; the upper end of the plain concrete layer (3) is provided with embedded parts (5) and foundation concrete (4), and backfill soil (6) is provided in the foundation pit outside the foundation concrete (4).

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