Ground anchor structure of prestressed concrete filled steel tube tower, wind power tower and construction method

Abstract

The invention relates to the technical field of wind power equipment, in particular to a prestressed concrete filled steel tube tower ground anchor structure, a wind power tower and a construction method, and the prestressed concrete filled steel tube tower ground anchor structure comprises a solid concrete foundation and lattice corner columns connected to the solid concrete foundation; the solid concrete foundation comprises a base body and an anchor seat protruding out of the surface of the base body, and a plurality of first anchor bolts and a plurality of second anchor bolts are embedded in the base body. The lower ends of the lattice type corner columns are fixedly connected with the first anchor bolts, and the upper ends of the second anchor bolts penetrate through the anchor bases to be fixedly connected with the anchoring assemblies. The top face of the anchor base is provided with a mounting groove used for containing a prestressed steel strand, and the lower end of the prestressed steel strand extends into the mounting groove and is limited and fixed through the anchoring assembly. A foundation cavity is omitted, the structural form and construction difficulty of the foundation are greatly simplified, and structural durability and compressive strength are improved.

Description

Technical Field

[0001] This invention relates to the field of wind power equipment technology, specifically to a prestressed steel pipe concrete tower ground anchor structure, a wind power tower, and a construction method. Background Technology

[0002] The prestressed steel-concrete composite lattice tower consists of an upper pure steel tower, a middle steel-concrete composite transition section, and lower prestressed steel-concrete composite lattice columns. The main structure of the prestressed steel-concrete composite lattice tower is composed of four inclined steel-concrete composite columns, which are connected to the upper steel tower through the transition structure. External prestressing cables are arranged inside the inclined columns. The prestressed steel-concrete composite lattice tower fully utilizes the advantages of the steel-concrete composite structure. The concrete is under triaxial compression, which significantly improves the ultimate strength, plasticity, and toughness of the concrete. At the same time, due to the supporting effect of the concrete on the steel, buckling failure of the steel is prevented, ensuring that the performance of the steel is fully utilized, producing a 1+1>2 effect. It fully utilizes the advantages of steel-concrete composite structures in high-rise structures, such as high load-bearing capacity and large lateral stiffness. In addition, the application of prestressing makes the entire cross-section of the concrete under compression, and the vertical steel pipe connecting flanges and bolts are always under compression. The use of prestressing reduces the average stress under fatigue load at the nodes of the lattice tower, thereby improving fatigue life. This also has good feasibility and economy.

[0003] Current wind turbine towers are developing towards taller hubs and larger capacities to improve wind energy utilization in low-wind-speed areas. Traditional lattice-type towers (such as quadrilateral or triangular structures) use four-point foundations, requiring large cavities at the bottom to accommodate the tensioning of prestressing tendons. Their main problems and drawbacks are as follows: 1) Functions and drawbacks of cavities: Cavities are used to accommodate tensioning equipment and anchoring ends, but complex piping systems need to be pre-embedded in the foundation, leading to difficulties in concrete pouring and a tendency for voids to occur. Waterproofing at the connection between the cavity and the corner column is difficult, and groundwater can easily seep in and corrode the prestressing tendons, significantly reducing the structural durability.

[0004] 2) Construction efficiency and cost issues: The high precision required for cavity formwork installation extends the construction period by more than 30%, and the over-excavation increases the workload. Tensioning operations must be carried out in narrow cavities, which poses high operational risks, and the transportation costs of large equipment are high (especially in mountainous wind farms).

[0005] 3) Structural performance limitations: The cavity weakens the integrity of the foundation, leading to stress concentration and easy cracking of concrete; at the same time, fatigue damage is likely to occur around the cavity under earthquake or wind vibration loads. Summary of the Invention

[0006] The purpose of this invention is to provide a prestressed steel pipe concrete tower ground anchor structure, wind turbine tower and construction method, which eliminates the foundation cavity, greatly simplifies the foundation structure and construction difficulty, and improves the structural durability and compressive strength.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows: In a first aspect, the present invention provides a prestressed steel-concrete composite tower ground anchor structure, comprising a solid concrete foundation and a lattice-type corner column connected to the solid concrete foundation; the solid concrete foundation includes a base body and an anchor seat protruding from the surface of the base body, wherein a plurality of first anchor bolts and a plurality of second anchor bolts are pre-embedded in the base body; the lower end of the lattice-type corner column is fixedly connected to the first anchor bolts, and the upper end of the second anchor bolt passes through the anchor seat and is fixedly connected to an anchoring assembly; the top surface of the anchor seat is provided with an installation groove for accommodating prestressed steel strands, the lower end of the prestressed steel strands extending into the installation groove and being limited and fixed by the anchoring assembly.

[0008] Furthermore, the anchoring assembly includes an anchor plate, a slider, and a rod. The top opening of the mounting groove has a notch adapted to the slider. The anchor plate is arranged on the top surface of the anchor seat. The upper end of the second anchor bolt passes through the anchor seat and the anchor plate and is connected to the second nut. The bottom surface of the anchor plate and the notch together form a groove that allows the slider to make linear reciprocating motion. The rod passes through the lattice-type corner post and the anchor seat from the side of the tower and is fixedly connected to the slider. The slider is driven to move through the rod.

[0009] Furthermore, the top of the slider near the mounting groove is provided with a limiting protrusion. When the slider is pushed into the mounting groove by the rod, it restricts the lower anchor head of the prestressed steel strand from moving axially. The limiting protrusion also engages with the side of the anchor plate near the mounting groove.

[0010] Furthermore, the lattice-type corner post includes an outer sleeve and an inner sleeve, with concrete poured between the outer sleeve and the inner sleeve; the inner sleeve includes an upper section and a lower section, with the inner diameter of the lower section being larger than that of the upper section; the inner wall of the lower section is clearance-fitted with the outer wall of the anchor; the lower section includes a vertical section and a horizontal section connected to the upper end of the vertical section, the free end of the horizontal section is connected to the lower part of the upper section, and the free end of the horizontal section is provided with a downwardly extending guide portion, which is fixedly connected to the outer wall of the upper section.

[0011] Furthermore, a first rib is fixed between the upper side of the horizontal section and the outer wall of the upper section, and a second rib is fixed between the lower side of the horizontal section and the outer wall of the guide portion.

[0012] Furthermore, a flange is fixed to the lower end of the lattice-shaped corner post, and the first anchor bolt passes through the flange and is threadedly connected to the first nut.

[0013] Furthermore, it also includes a drain pipe that communicates with the bottom of the mounting groove, the outlet of which extends outside the tower.

[0014] Furthermore, the upper anchor head at the upper end of the prestressed steel strand is fixedly connected to the tensioning platform at the upper end of the lattice-type corner column.

[0015] Secondly, the present invention provides a wind turbine tower, which includes the aforementioned prestressed steel-concrete composite tower ground anchor structure.

[0016] Thirdly, the present invention provides a construction method for a prestressed steel-concrete composite tower ground anchor structure, comprising: The foundation concrete pouring construction is carried out, and a number of first anchor bolts and a number of second anchor bolts are pre-embedded in the foundation. The upper ends of the first anchor bolts and the second anchor bolts protrude from the upper surface of the foundation, providing installation points for the lower end of the lattice corner column or anchoring components. The anchoring assembly is installed in the mounting slot of the foundation, and then the lower end of the lattice corner post is fixedly connected to the first anchor bolt. The prestressed steel strands are threaded through the internal channel of the lattice-shaped corner column and transported downwards to the installation slot of the anchor in the foundation. The prestressed steel strands are then locked in place by the anchoring components to complete the construction.

[0017] The present invention has the following unexpected beneficial effects: 1. The prestressed steel tube concrete tower ground anchor structure of this invention adopts an integral solid concrete foundation, completely eliminating the large cavity of traditional tower foundations. This fundamentally solves the problems of concrete pouring defects (such as voids) caused by the pre-embedded complex pipes in traditional cavities, as well as the difficulties in waterproofing the connection between the cavity and the corner column, and the problem of groundwater seepage corroding the prestressing tendons. The solid concrete foundation has no splicing gaps or seepage channels, which can effectively protect the prestressed steel strands and the second anchor bolts from environmental erosion, and significantly extend the service life of the structure. At the same time, the solid structure avoids the weakening of the foundation's integrity by the cavity, eliminates the risk of stress concentration around the cavity, reduces the probability of concrete cracking, and improves the overall compressive and fatigue bearing capacity of the foundation, making it more suitable for the long-term stress requirements of high-hull, large-capacity towers. Furthermore, through the dual connection design of the first anchor bolt connecting the lattice corner column and the second anchor bolt working with the anchoring components to fix the prestressed steel strands, reliable connection between the lattice corner column and the foundation, and between the prestressing system and the foundation is achieved. On the one hand, the lattice-type corner columns are directly fixed to the solid foundation through the first anchor bolt, eliminating the need for traditional hollow transition components, reducing weak points in the connection, enhancing the coordinated load-bearing capacity of the corner columns and the foundation, and improving the overall lateral stiffness and seismic performance. On the other hand, the cooperation between the second anchor bolt and the anchoring components can stably limit the prestressed steel strands, ensuring that the prestress is effectively transferred to the foundation, avoiding prestress loss, further ensuring the full-section compression state of the concrete, and reducing the risk of structural cracking.

[0018] 2. The prestressed steel pipe concrete tower ground anchor structure of this invention eliminates the need for traditional foundation procedures such as cavity excavation, cavity formwork installation, and complex pipeline pre-embedding. The solid concrete foundation only requires conventional pouring processes, eliminating the need for additional high-precision formwork positioning and over-excavation related to the cavity. Simultaneously, the lattice-type corner columns are directly fixed by the first anchor bolt, and the prestressed steel strands are limited by the installation groove and anchoring components on the top surface of the anchor seat, eliminating the need for anchoring operations in the narrow space of the traditional cavity. The overall construction process is simpler, reducing cumbersome specialized construction steps, lowering the technical threshold and operational errors, and helping to shorten the construction cycle. Furthermore, due to the top tensioning and bottom anchoring process, the lower end of the prestressed steel strands in this structure is fixed to the anchoring components through the installation groove, eliminating the need for tensioning operations within the underground cavity. This avoids the risks of operating large equipment in the narrow underground space as in traditional solutions, reducing safety hazards such as falls from heights and equipment collisions. It also eliminates the need to transport large underground tensioning equipment, reducing the difficulty of equipment scheduling and safety management during construction.

[0019] 3. Because the solid concrete foundation of this invention has no cavity structure, there is no need for special waterproofing treatment of cavities. This completely solves the problem of traditional foundations being unusable in humid or underwater environments due to water seepage in cavities. It can be directly applied to humid sites such as underwater rivers and rainy mountainous areas, significantly expanding the applicable geographical range of the tower and better aligning with the development trend of onshore wind power expanding into low-wind-speed areas (including humid and water-rich areas). Furthermore, the solid concrete foundation has superior load-bearing capacity. Combined with the rigid connection between the lattice-type corner columns and the foundation, and the stable anchoring of the prestressed steel strands, the overall structure can better transmit the vertical loads and horizontal wind vibration loads of high-hub, large-capacity towers, avoiding localized overload. Simultaneously, the installation groove design on the top surface of the anchor provides precise limiting space for the prestressed steel strands, ensuring uniform prestress distribution and further optimizing the structural stress state to meet the mechanical requirements for long-term stable operation of large wind turbine towers. Attached Figure Description

[0020] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention.

[0021] Figure 1 A schematic diagram of the prestressed steel tube concrete tower ground anchor structure described in this invention is shown.

[0022] Figure 2 It shows Figure 1 A magnified view of a portion of region A.

[0023] Figure 3 An enlarged schematic diagram of the anchoring assembly is shown.

[0024] Figure 4 It shows Figure 2 A magnified view of a portion of region C.

[0025] Figure 5 It shows Figure 1 A magnified view of a portion of region B.

[0026] In the figure, 1—lattice-type corner column, 11—outer sleeve, 12—inner sleeve, 121—upper section, 122—lower section, 1221—vertical section, 1222—horizontal section, 1223—guide section, 123—first rib, 124—second rib, 13—flange; 2—Foundation, 21—Base, 22—Anchor seat, 23—First anchor bolt, 24—Second anchor bolt, 25—Installation groove, 26—Notch; 3—Anchoring component, 31—Anchor plate, 32—Slider, 321—Limiting protrusion, 33—Rod; 4—Prestressed steel strand, 41—Lower anchor head, 42—Lower cap, 43—Upper anchor head, 44—Upper cap; 5—First nut, 6—Second nut, 7—Drain pipe. Detailed Implementation

[0027] The embodiments of the present invention will be described below with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention and not for limiting the scope of protection of the present invention.

[0028] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. The drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0029] In one embodiment, see Figures 1 to 3As shown, this invention discloses a prestressed steel-concrete composite tower anchor structure, including a solid concrete foundation 2 and a lattice-type corner column 1 connected to the solid concrete foundation 2. The solid concrete foundation 1 includes a base 21 and an anchor seat 22 protruding from the surface of the base 21. Several first anchor bolts 23 and several second anchor bolts 24 are pre-embedded in the base 21. The lower end of the lattice-type corner column 1 is fixedly connected to the first anchor bolt 23, and the upper end of the second anchor bolt 24 passes through the anchor seat 22 and is fixedly connected to the anchoring assembly 3. The top surface of the anchor seat 22 is provided with an installation groove 25 for accommodating prestressed steel strands 4. The lower end of the prestressed steel strands 4 extends into the installation groove 25 and is fixed by the anchoring assembly 3.

[0030] The prestressed steel pipe concrete tower ground anchor structure of this invention adopts an integral solid concrete foundation 2, completely eliminating the large cavity of traditional tower foundations. This fundamentally solves the problems of concrete pouring defects (such as voids) caused by the pre-embedded complex pipes in traditional cavities, as well as the difficulties in waterproofing the connection between the cavity and the corner column, and the problem of groundwater seepage corroding the prestressing tendons. Furthermore, since the foundation 2 is a solid concrete structure, there are no splicing gaps or seepage channels, effectively protecting the prestressed steel strands 4 and the second anchor bolts 24 from environmental erosion, significantly extending the service life of the structure. At the same time, the solid structure avoids the weakening of the overall integrity of the foundation 1 by the cavity, eliminates the risk of stress concentration around the cavity, reduces the probability of concrete cracking, and improves the overall compressive and fatigue bearing capacity of the foundation 2, making it more suitable for the long-term stress requirements of high-hull, large-capacity towers. This embodiment completely eliminates the large cavity at the bottom of the traditional tower and adopts an integral solid concrete foundation 2, thereby eliminating the risk of water seepage and corrosion caused by the cavity and the construction problems of complex pre-embedded pipes, significantly improving the structural durability; at the same time, it increases the compressive strength of foundation 2 by more than 20%, solves the defect of stress concentration cracking, and reduces the construction difficulty and defect rate.

[0031] This invention employs a dual connection design: a first anchor bolt 23 connects the lattice-shaped corner column 1, and a second anchor bolt 24, in conjunction with an anchoring assembly 3, fixes the prestressed steel strand 4. This achieves a reliable connection between the lattice-shaped corner column 1 and the foundation 2, and between the prestressing system and the foundation 2. On one hand, the lattice-shaped corner column 1 is directly fixed to the solid foundation 2 via the first anchor bolt 23, eliminating the need for traditional hollow transition components. This lightweight design reduces transportation costs by 15% and decreases weak points in the connection, enhancing the collaborative load-bearing capacity of the lattice-shaped corner column 1 and the foundation 2, and improving the overall lateral stiffness and seismic performance of the tower. On the other hand, the cooperation between the second anchor bolt 24 and the anchoring assembly 3 provides stable restraint for the prestressed steel strand 4, ensuring effective prestress transfer to the foundation 2, preventing prestress loss, further guaranteeing the full-section compression state of the concrete, and reducing the risk of structural cracking.

[0032] The prestressed steel pipe concrete tower ground anchor structure of this invention eliminates the need for traditional foundation cavity excavation, cavity formwork installation, and complex pipeline pre-embedding processes. The solid concrete foundation 2 only requires conventional pouring procedures, without the need for additional high-precision formwork positioning and over-excavation related to the cavity. Simultaneously, the lattice-type corner columns 1 are directly fixed by the first anchor bolt 23, and the prestressed steel strands 4 are limited by the installation groove 25 on the top surface of the anchor seat 22 and the anchoring component 3, eliminating the need for anchoring operations in the narrow space of the traditional cavity. The overall construction process is simpler, reducing cumbersome specialized construction steps, lowering the technical threshold and operational errors, and helping to shorten the construction cycle. Furthermore, due to the top tensioning and bottom anchoring process, the lower end of the prestressed steel strands in this structure is fixed to the anchoring component through the installation groove, eliminating the need for tensioning operations within the underground cavity. This avoids the risks of operating large equipment in the narrow underground space of traditional solutions, reducing safety hazards such as falls from heights and equipment collisions. It also eliminates the need to transport large underground tensioning equipment, reducing the difficulty of equipment scheduling and safety management during construction.

[0033] This invention, with its solid concrete foundation and absence of cavities, eliminates the need for special waterproofing treatment of cavities, completely solving the problem of traditional foundations being unsuitable for use in humid or underwater environments due to water seepage in cavities. It can be directly applied to humid sites such as underwater rivers and rainy mountainous areas, significantly expanding the applicable geographical range of the tower and better aligning with the development trend of onshore wind power expanding into low-wind-speed areas (including humid and waterlogged regions). Furthermore, the solid concrete foundation 2 has superior load-bearing capacity. Combined with the rigid connection between the lattice-type corner columns 1 and the foundation 2, and the stable anchoring of the prestressed steel strands 4, the overall structure can better transmit the vertical loads and horizontal wind vibration loads of high-hub, large-capacity towers, avoiding localized overload. Simultaneously, the mounting groove 25 on the top surface of the anchor 22 provides precise limiting space for the prestressed steel strands 4, ensuring uniform prestress distribution and further optimizing the structural stress state to meet the mechanical requirements for long-term stable operation of large wind turbine towers. The foundation 2 does not require waterproofing and can be directly placed in an underwater environment, expanding application scenarios, comprehensively optimizing concrete volume and shortening the construction period by 40%, thus significantly improving economic efficiency.

[0034] As a preferred embodiment of the present invention, see Figure 2 and Figure 3 As shown, the anchoring assembly 3 includes an anchor plate 31, a slider 32, and a rod 33. The top opening of the mounting groove 25 is provided with a notch 26 that matches the slider 32. The anchor plate 31 is arranged on the top surface of the anchor seat 22. The upper end of the second anchor bolt 24 passes through the anchor seat 22 and the anchor plate 31 and is connected to the second nut 6. The bottom surface of the anchor plate 31 and the notch 26 together form a groove that allows the slider 32 to make linear reciprocating motion. The rod 33 passes through the lattice corner post 1 and the anchor seat 22 from the side of the tower and is fixedly connected to the slider 32. The slider 32 is driven to move through the rod 33.

[0035] In this preferred embodiment, the groove formed by the bottom surface of the anchor plate 31 of the anchoring component 3 and the notch 26 on the top surface of the anchor seat 22 provides a stable linear motion trajectory for the slider 32, ensuring that the slider 32 can accurately fit the lower anchor head 41 of the prestressed steel strand 4 and apply locking force, avoiding the problems of anchoring offset and uneven prestress transmission caused by irregular limiting space in traditional anchoring methods; at the same time, the matching design of the slider 32 and the groove can make the locking force act evenly on the prestressed steel strand 4, ensuring that the prestress is effectively transmitted to the solid concrete foundation 2, ensuring that the concrete of the foundation 2 is always under full cross-sectional compression, and reducing the risk of structural cracking.

[0036] The upper end of the second anchor bolt 24 passes through the anchor seat 22 and the anchor plate 31 and is fixed by the second nut 6, so that the anchor plate 31 and the anchor seat 22 form a rigid connection. On the one hand, the anchor plate 31 can serve as a transition carrier for prestress transfer, distributing the tension of the prestressed steel strand 4 evenly to the anchor seat 22 and the solid foundation 2, avoiding local stress concentration. On the other hand, the synergistic effect of the anchor plate 31 and the second anchor bolt 24 can limit the deformation of the top surface of the anchor seat 22, reduce the displacement of the anchoring system under long-term prestress, further ensure the reliability of the anchoring, and adapt to the stress requirements of high hub, large capacity towers that have been subjected to wind vibration and seismic loads for a long time.

[0037] The rod 33 passes through the lattice-shaped corner column 1 and anchor seat 22 from the side of the tower and is then fixed to the slider 32. Operators do not need to enter the underground space; they only need to move the slider 32 via the rod 33 from the side of the tower to lock the prestressed steel strand 4. This completely eliminates the complex operation of manually adjusting the anchoring components in the narrow underground space of traditional cavity foundations, significantly reducing construction difficulty. At the same time, it eliminates the need for large underground tensioning equipment, reducing equipment transportation and scheduling costs.

[0038] Furthermore, the design of the rod 33 penetrating through the lattice corner post 1 makes the anchoring component 3 and the corner post form a linked whole. On the one hand, the lattice corner post 1 can provide lateral support for the rod 33, avoiding displacement of the slider 32 caused by long-term stress deformation of the rod 33; on the other hand, there is no need to set additional anchoring transition components between the lattice corner post 1 and the foundation 2, simplifying the connection structure between the lattice corner post 1 and the foundation 2, and further improving the overall seismic performance.

[0039] As a preferred embodiment of the present invention, see Figure 3 As shown, the top of the slider 32 near the mounting groove 25 is provided with a limiting protrusion 321. When the slider 32 is pushed into the mounting groove 25 by the rod 33, the lower anchor head 41 at the lower end of the prestressed steel strand 4 is restricted to move axially. The limiting protrusion 321 is in a limiting fit with the side of the anchor plate 31 near the mounting groove 25.

[0040] The design of the limiting protrusion 321 eliminates the need for additional locking accessories (such as bolts or pins). The slider 32 is simply pushed into the mounting groove 25 via the rod 33. When tensioning is applied to the upper end of the prestressed steel strand 4, the prestressed steel strand 4 is tightened as a whole. Consequently, the lower anchor head 41 at the lower end applies an upward force to the limiting protrusion 321, causing the limiting protrusion 321 to move upward. This automatically forms axial and radial limits with the lower anchor head 41 and the anchor plate 31, preventing the lower anchor head 41 from moving upward. At the same time, the limiting protrusion 321 prevents the slider 32 from detaching radially along the groove. This completely simplifies the complex process of manually adjusting the anchor position and additionally tightening and locking in traditional anchoring methods. Operators can complete the anchoring by controlling the rod 33 from the side of the tower, without having to enter underground spaces or narrow areas to work.

[0041] As a preferred embodiment of the present invention, see Figures 2 to 4 As shown, the lattice-type corner post 1 includes an outer sleeve 11 and an inner sleeve 12, with concrete poured between the outer sleeve 11 and the inner sleeve 12. The inner sleeve 12 includes an upper section 121 and a lower section 122, with the inner diameter of the lower section 122 being larger than that of the upper section 121; the inner wall of the lower section 122 is clearance-fitted with the outer wall of the anchor seat 22; the lower section 122 includes a vertical section 1221 and a horizontal section 1222 connected to the upper end of the vertical section 1221, the free end of the horizontal section 1222 being connected to the lower part of the upper section 121, and the free end of the horizontal section 1222 being provided with a downwardly extending guide portion 1223, which is fixedly connected to the outer wall of the upper section 121.

[0042] In this preferred embodiment, the lattice-type corner column 1 adopts a double-sleeve structure. After the interlayer space is filled with concrete, the concrete is simultaneously constrained by the outer sleeve 11 and supported by the inner sleeve 12, forming a two-way steel pipe constrained concrete system. This makes the three-dimensional compression state of the concrete more complete, which can further improve the ultimate strength and plastic toughness of the concrete. At the same time, the inner sleeve 12 can assist the outer sleeve 11 in resisting buckling deformation, avoiding the steel from becoming unstable due to local stress overload, and can better bear the vertical load and horizontal wind vibration load of high hub and large capacity tower.

[0043] The inner sleeve 12 adopts a segmented design, constructing a more reasonable force transmission channel. The upper load of the tower borne by the upper segment 121 can be evenly distributed to the vertical segment 1221 of the lower segment 122 through the horizontal segment 1222, and then transferred to the solid concrete foundation 2 by the vertical segment 1221, avoiding the direct concentration of load at the connection node between the lattice corner column 1 and the foundation 2. At the same time, the guide part 1223 at the free end of the horizontal segment 1222 connects to the outer wall of the upper segment 121, which can further balance the force difference between the upper segment 121 and the lower segment 122, reduce the stress mutation caused by the cross-sectional change, and improve the overall fatigue resistance of the corner column.

[0044] As a preferred embodiment of the present invention, see Figure 4 As shown, a first rib 123 is fixed between the upper side of the horizontal segment 1222 and the outer wall of the upper segment 121, and a second rib 124 is fixed between the lower side of the horizontal segment 1222 and the outer wall of the guide portion 1223.

[0045] The free end of the horizontal segment 1222 connects to the lower part of the upper segment 121, and the guide part 1223 is fixed to the outer wall of the upper segment 121, forming a triangular connection area of ​​the upper segment 121, the horizontal segment 1222, and the guide part 1223. This area is a critical node for the force transmission of the corner column and is prone to stress concentration due to sudden load changes (such as vertical loads on the upper part of the tower and horizontal wind vibration loads). The first rib 123 is fixed between the upper side of the horizontal segment 1222 and the outer wall of the upper segment 121, which can directly form a rigid support at this connection point, evenly distributing the load transmitted from the upper segment 121 to the horizontal segment 1222 to the entire cross section of the horizontal segment 1222, avoiding deformation or cracking of the steel caused by local stress overload. At the same time, the presence of the first rib 123 increases the connection contact area between the horizontal segment 1222 and the upper segment 121, improves the shear strength of the welded (or fixed) parts, and ensures that the corner column can stably bear the long-term load of the high hub and large capacity tower.

[0046] The second rib 124 corresponds to the first rib 123, so that the horizontal section 1222 is in a stable state of bidirectional support, which further improves the overall stiffness of the horizontal section 1222 and reduces fatigue damage under long-term load.

[0047] As a preferred embodiment of the present invention, see Figure 2 As shown, a flange 13 is fixed at the lower end of the lattice-type corner post 1, and the first anchor bolt 23 passes through the flange 13 and is threadedly connected to the first nut 5.

[0048] This preferred embodiment can form a multi-point uniformly stressed connection system. The vertical load, horizontal wind vibration load, and seismic load of the upper part of the tower borne by the lattice corner column 1 can be evenly distributed to multiple first anchor bolts 23 through the flange surface, and then transferred to the solid concrete foundation 2 by the first anchor bolts 23, avoiding the local stress concentration problem caused by traditional non-flange connections (such as direct welding). At the same time, the rigid connection between the flange 13 and the first anchor bolts 23 can ensure that there is no relative displacement between the lattice corner column 1 and the foundation 2, ensuring that the prestress applied by the prestressed steel strand 4 effectively acts on the concrete of the foundation 2, maintaining the full-section compression state of the concrete.

[0049] The threaded connection of the first anchor bolt 23 and the first nut 5 provides reliable pull-out resistance, preventing the corner column from separating from the foundation under wind vibration or seismic loads. Simultaneously, the contact surface between the flange 13 and the top surface of the foundation 2, along with the first anchor bolt 23, jointly resists horizontal shear force, reducing the lateral displacement of the corner column under horizontal loads. Compared to the indirect connection method of transition components in traditional hollow foundations, this eliminates intermediate connection links, reduces weak points, and makes the connection between the corner column and the foundation 2 more rigid, better adapting to the long-term vertical + horizontal + alternating combined load conditions of high-hub, large-capacity towers.

[0050] As a preferred embodiment of the present invention, see Figure 2 As shown, it also includes a drain pipe 7 that communicates with the bottom of the mounting groove 25, and the outlet of the drain pipe 7 extends out of the tower.

[0051] Although the cavity-free foundation 2 of this invention significantly reduces seepage paths, the installation groove 25, which serves as the confinement space for the lower anchor head 41 of the prestressed steel strand 4, may still experience localized water accumulation due to atmospheric precipitation, surface seepage, or concrete condensation. By using a drainage pipe 7 connected to the bottom of the installation groove 25, the accumulated water can be actively drained to the outside of the tower through the outlet, preventing long-term water retention within the installation groove 25. This fundamentally prevents water from contacting the lower anchor head 41, slider 32, anchor plate 31, and other metal components of the prestressed steel strand 4, mitigating the risk of metal corrosion and ensuring the long-term stable transmission of prestress by the anchoring system.

[0052] If the concrete around the mounting groove 25 is in contact with water for a long time, it is prone to cracking and peeling due to water penetration, freeze-thaw cycles (in cold northern regions), or chemical erosion (in humid environments containing salt and alkali), which weakens the integrity of the foundation and anchor. The active drainage function of the drainage pipe 7 can keep the mounting groove 25 and the surrounding concrete dry, avoid the deterioration of concrete performance caused by water damage, and reduce stress concentration problems caused by concrete damage.

[0053] As a preferred embodiment of the present invention, see Figure 1 and Figure 5 As shown, the upper anchor head 43 at the upper end of the prestressed steel strand 4 is fixedly connected to the tensioning platform at the upper end of the lattice-type corner column 1.

[0054] This preferred embodiment transfers the tensioning operation of the prestressed steel strand 4 to the tensioning platform at the top of the lattice-type corner column 1. Unlike traditional solutions, it eliminates the need to set up a large cavity at the bottom of the foundation 2 to accommodate the tensioning equipment. This completely eliminates the problems caused by the cavity, such as complex pre-embedded pipes, numerous defects in concrete pouring, and difficulties in waterproofing. It is in perfect harmony with the structural advantages of solid concrete foundations, which have no seepage channels and strong integrity, and ensures the implementation of the cavity-free foundation design from the source of the process.

[0055] The tensioning platform is located at the top of the lattice corner column 1. Operators can use the platform to stably tension the prestressed steel strands 4. The fixed connection between the upper anchor head 43 and the tensioning platform ensures that the axis of the steel strands is always consistent with the design direction during the tensioning process, avoiding prestress deviation caused by misalignment of tensioning equipment in traditional underground narrow spaces. At the same time, the reliable fixation of the upper anchor head 43 to the platform after tensioning can stably transfer the prestress to the lattice corner column 1, and then to the foundation 2 through the lattice corner column 1, ensuring that the concrete of the foundation 2 is always under full-section compression.

[0056] In this preferred embodiment, a tensioning platform is set up at the top of the tower, i.e., the upper end of the lattice-shaped corner column 1, to complete the tensioning operation. The prestressed steel strands 4 pass through the internal channels of the lattice-shaped corner column 1, and are locked at the bottom by a push-pull locking slider 32 and an anchor plate 31 system, completely avoiding the risks of working in narrow underground spaces, saving the transportation costs of large equipment, and shortening the construction period by 40%. Because the lattice-shaped corner column 1 has pre-reserved prestressed channels, it achieves triaxial compression of the concrete, improving the synergistic enhancement of bearing capacity and buckling resistance of the steel.

[0057] Further, see Figure 2 As shown, a steel lower cap 42 is externally sealed to the lower anchor head 41. (See also...) Figure 5 As shown, the upper anchor head 43 is externally sealed with a steel upper cap 44.

[0058] As key anchoring nodes for the prestressed steel strand 4, the upper anchor head 43 and lower anchor head 41 may still be exposed to the external environment. The lower anchor head 41 is located in the installation groove 25 and is easily exposed to condensation and surface seepage. The upper anchor head 43 is located on the tensioning platform at the top of the tower and is susceptible to rain and sandstorms. The steel lower cap 42 and upper cap 44 completely enclose the anchor head through a sealed connection (such as with sealant and gaskets), which can physically isolate water, dust, salt (in coastal or saline-alkali areas) and other corrosive media, prevent the metal parts of the anchor head (such as anchorages and connectors) from rusting, and prevent problems such as reduced anchoring force and jamming caused by corrosion of the anchor head, ensuring the long-term stable transmission of prestress to the foundation 2 and the tower.

[0059] Steel materials possess high strength and resistance to deformation. Compared to traditional plastic or rubber protective components, the steel lower cap 42 and upper cap 44 can better resist the effects of extreme environments: in cold northern regions, they can prevent the protective components from becoming brittle due to low temperatures; in high-temperature and sun-exposed environments, they can prevent the protective components from aging and deforming; at the same time, they can withstand the mechanical impact of wind, sand, and gravel on the anchor head, preventing damage to the external structure of the anchor head. In addition, the steel caps can reduce the impact of temperature changes on the thermal expansion and contraction of the prestressed cables inside the anchor head, maintaining the stability of the anchor head under stress.

[0060] In one embodiment, the present invention provides a wind turbine tower, which includes the above-described prestressed steel-concrete composite tower ground anchor structure.

[0061] The solid concrete foundation 2 and the lattice-type corner column 1 (double sleeve + sandwich concrete) in the ground anchor structure form a synergistic force-bearing system: the solid foundation 2 provides strong vertical bearing and pull-out resistance, while the lattice-type corner column 1, through the combined effect of the outer sleeve 11 confining the concrete and the inner sleeve 12 assisting in buckling resistance, evenly transfers the vertical load (including the equipment's self-weight) and horizontal wind vibration load transmitted from the upper nacelle and hub of the tower to the foundation 2. At the same time, the prestressed steel strands 4, through the top tensioning-bottom anchoring system, ensure that the entire cross-section of the foundation 2 concrete is under compression, preventing cracking and further ensuring the stability of the overall structure under long-term composite loads, which can stably adapt to the stress requirements of high-hub, large-capacity wind turbines.

[0062] Compared to traditional wind turbine towers with hollow foundations, this tower eliminates the cavity through a ground anchor structure, completely removing weaknesses such as weakened foundation integrity, stress concentration, and water seepage corrosion caused by cavities. The solid foundation 2 has no water seepage channels, preventing corrosion of the prestressed steel strands 4 and the second anchor bolt 24, thus extending structural durability. The lattice-type corner columns 1 are directly connected to the foundation 2 via flanges 13 and the first anchor bolt 23, reducing transition components and lowering the risk of joint loosening under earthquakes or strong wind loads. Simultaneously, the prestressing system reduces the average stress of fatigue loads at the joints, and combined with the rigid connection of the ground anchor structure, significantly extends the overall fatigue life of the tower.

[0063] The solid concrete foundation 2 of the ground anchor structure does not require special waterproofing treatment for the cavity. Combined with the double-sleeve closed interlayer concrete design of the lattice corner column 1, the wind turbine tower can be directly installed in humid environments such as below river water and in rainy mountainous areas: the solid foundation 2 has no water seepage channels, avoiding groundwater corrosion of the foundation components; the outer sleeve 11 of the lattice corner column 1 isolates external moisture, protecting the interlayer concrete and the inner sleeve 2, solving the problem of easy corrosion of traditional cavitary towers in humid environments, and greatly expanding the applicable geographical range of wind turbine towers.

[0064] In one embodiment, the present invention provides a construction method for a prestressed steel-concrete composite tower ground anchor structure, comprising: The foundation concrete pouring construction is carried out, and a number of first anchor bolts and a number of second anchor bolts are pre-embedded in the foundation. The upper ends of the first anchor bolts and the second anchor bolts protrude from the upper surface of the foundation, providing installation points for the lower end of the lattice corner column or anchoring components. The anchoring assembly is installed in the mounting slot of the foundation, and then the lower end of the lattice corner post is fixedly connected to the first anchor bolt. The prestressed steel strand 4 is threaded through the cable. The prestressed steel strand 4 is transported from the upper end of the internal channel of the lattice corner column 1 downward to the installation groove 25 of the anchor seat 22 of the foundation 2. The prestressed steel strand 4 is then locked by the anchoring component 3 to complete the construction.

[0065] The foundation 2 pouring stage requires no cavity excavation or complex pipe pre-embedding, only conventional concrete pouring and anchor bolt pre-embedding; during the tower assembly stage, the lattice-type corner column 1 is quickly connected to the first anchor bolt 23 via flange 13, eliminating the need for on-site welding and calibration; during the prestressing stage, the operation is completed through the tensioning platform at the top of the tower, eliminating the need for underground work. The entire process eliminates the specialized procedures of traditional tower construction, such as cavity formwork installation and underground tensioning equipment scheduling, significantly shortening the construction cycle.

[0066] Furthermore, the ground anchor structure avoids the narrow space of traditional underground tower cavities for operations. All foundation 2 connections and prestressing tensioning operations are completed on the ground or in open spaces above the tower, reducing safety hazards such as falls from heights and equipment collisions. At the same time, flange 13 connections, top tensioning, and other procedures are all carried out using standardized operations, eliminating the need for high-precision underground construction technology and reducing the professional skill requirements for construction personnel. This makes it particularly suitable for wind power construction in complex sites such as mountainous areas and rainy areas.

[0067] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments, and various changes can be made within the scope of knowledge possessed by those skilled in the art without departing from the spirit of the present invention. Furthermore, the embodiments of the present invention and the features thereof can be combined with each other unless otherwise specified.

Claims

1. A prestressed steel-concrete composite tower ground anchor structure, characterized in that: Includes a solid concrete foundation (2) and a lattice corner column (1) connected to the solid concrete foundation (2); The solid concrete foundation (2) includes a base (21) and an anchor (22) protruding from the surface of the base (21). Several first anchors (23) and several second anchors (24) are pre-embedded in the base (21). The lower end of the lattice corner column (1) is fixedly connected to the first anchor (23), and the upper end of the second anchor (24) passes through the anchor (22) and is fixedly connected to the anchoring assembly (3). The top surface of the anchor (22) is provided with an installation groove (25) for accommodating the prestressed steel strand (4). The lower end of the prestressed steel strand (4) extends into the installation groove (25) and is fixed by the anchoring component (3).

2. The prestressed steel-concrete composite tower ground anchor structure according to claim 1, characterized in that: The anchoring assembly (3) includes an anchor plate (31), a slider (32), and a rod (33). The top opening of the mounting groove (25) is provided with a notch (26) that is adapted to the slider (32). The anchor plate (31) is arranged on the top surface of the anchor seat (22). The upper end of the second anchor bolt (24) passes through the anchor seat (22) and the anchor plate (31) and is connected to the second nut (6). The bottom surface of the anchor plate (31) and the notch (26) enclose a groove that allows the slider (32) to make linear reciprocating motion. The rod (33) passes through the lattice corner post (1) and the anchor seat (22) from the side of the tower and is fixedly connected to the slider (32). The slider (32) is driven to move by the rod (33).

3. The prestressed steel-concrete composite tower ground anchor structure according to claim 2, characterized in that: The slider (32) has a limiting protrusion (321) at the top of the side near the mounting groove (25). When the slider (32) is pushed into the mounting groove (25) by the rod (33), the lower anchor head (41) at the lower end of the prestressed steel strand (4) is restricted to move axially. The limiting protrusion (321) is in a limiting fit with the side of the anchor plate (31) near the mounting groove (25).

4. The prestressed steel-concrete composite tower ground anchor structure according to claim 1, characterized in that: The lattice-type corner column (1) includes an outer sleeve (11) and an inner sleeve (12), with concrete poured between the outer sleeve (11) and the inner sleeve (12); The inner sleeve (12) includes an upper section (121) and a lower section (122), the inner diameter of the lower section (122) is larger than the inner diameter of the upper section (121); the inner wall of the lower section (122) is in clearance fit with the outer wall of the anchor (22); The lower section (122) includes a vertical section (1221) and a horizontal section (1222) connected to the upper end of the vertical section (1221). The free end of the horizontal section (1222) is connected to the lower part of the upper section (121), and the free end of the horizontal section (1222) is provided with a downwardly extending guide portion (1223). The guide portion (1223) is fixedly connected to the outer wall of the upper section (121).

5. The prestressed steel-concrete composite tower ground anchor structure according to claim 4, characterized in that: A first rib (123) is fixed between the upper side of the horizontal section (1222) and the outer wall of the upper section (121), and a second rib (124) is fixed between the lower side of the horizontal section (1222) and the outer wall of the guide portion (1223).

6. The prestressed steel-concrete composite tower ground anchor structure according to claim 1, characterized in that: The lower end of the lattice-type corner post (1) is fixed with a flange (13), and the first anchor bolt (23) passes through the flange (13) and is threadedly connected to the first nut (5).

7. The prestressed steel-concrete composite tower ground anchor structure according to claim 1, characterized in that: It also includes a drain pipe (7) that communicates with the bottom of the mounting groove (25), the outlet of which extends out of the tower.

8. The prestressed steel-concrete composite tower ground anchor structure according to claim 1, characterized in that: The upper anchor head (43) at the upper end of the prestressed steel strand (4) is fixedly connected to the tensioning platform at the upper end of the lattice corner column (1).

9. A wind turbine tower, characterized in that: Including the prestressed steel tube concrete tower ground anchor structure as described in any one of claims 1 to 8.

10. A construction method for a prestressed steel-concrete composite tower ground anchor structure, characterized in that, include: Concrete pouring construction of foundation (2) is carried out, and several first anchor bolts (23) and several second anchor bolts (24) are pre-embedded in the foundation (2). The upper ends of the first anchor bolts (23) and the second anchor bolts (24) protrude from the upper surface of the foundation (2) to provide installation points for the lower end of the lattice corner column (1) or the anchoring component (3). Install the anchoring component (3) in the mounting groove (25) of the foundation (2), and then fix the lower end of the lattice corner post (1) to the first anchor bolt (23); The prestressed steel strand (4) is threaded through the cable. The prestressed steel strand (4) is transported from the upper end of the internal channel of the lattice corner column (1) to the installation groove (25) of the anchor seat (22) of the foundation (2). The prestressed steel strand (4) is locked by the anchoring component (3) to complete the construction.

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