Local grouting combined ring stiffened double-steel-pipe wind power tower structure

Abstract

The application relates to the technical field of wind power generation, in particular to a double-steel-pipe wind power tower cylinder structure reinforced by local grouting combined rings, which comprises multiple cylinder segments, each cylinder segment is composed of a double-layer cavity formed by an inner steel plate and an outer steel plate, an end plate provided with stiffening ribs and reserved bolt holes is arranged at the end, internal annular stiffening ribs, pegs and local grouting concrete are arranged at the end and the high stress area in the middle to form a reinforced segment, and a 'claw'-shaped connecting piece is arranged at the non-grouting segment to realize the stress coordination of the double steel pipes. The application can significantly improve the bending and torsion resistance, reduce the concrete consumption and facilitate the modular assembly and construction.

Description

Technical Field

[0001] This invention relates to the field of wind power generation equipment, and more particularly to a double steel pipe wind turbine tower structure with localized grouting combined ring reinforcement. Background Technology

[0003] With the rapid development of wind power technology, the height and load-bearing capacity requirements of wind turbine towers, as key structural components supporting wind turbine units, are constantly increasing. Traditional wind turbine towers mostly adopt a single steel pipe structure, which, although simple in construction and convenient in installation, has limited bending and torsional stiffness, making it difficult to meet the structural stability and load-bearing performance requirements of high towers. To improve the overall performance of the tower, a double steel pipe structure has emerged in recent years, forming a composite structure by pouring concrete between the inner and outer steel pipes to enhance overall stiffness and stability. However, the existing integral grouting scheme has problems such as large concrete consumption, structural weight, transportation difficulties, and complex on-site construction. Especially in ultra-high towers, it not only significantly increases material and hoisting costs but also brings safety risks associated with high-altitude operations. In addition, traditional towers mostly use integrated molding or welding connections, which are not conducive to modular transportation and rapid on-site assembly. Furthermore, there is a lack of flexible and effective local reinforcement methods in the high-stress areas in the middle of the tower section, making it difficult to adapt to engineering needs under different heights and complex load conditions. In terms of connection construction, conventional connectors typically only reinforce for forces in a single direction, failing to effectively coordinate the transfer of internal forces under bending and torsional loads simultaneously. This can easily lead to localized stress concentrations, affecting structural durability and service life. Therefore, there is an urgent need for a new type of wind turbine tower structure that combines high bending and torsional resistance, lightweight design, ease of transportation and installation, flexible local reinforcement, and reliable connections to overcome the shortcomings of existing technologies in terms of structural performance, construction efficiency, and economy. Summary of the Invention

[0004] This invention addresses the technical challenges faced by existing wind turbine towers as they evolve towards ultra-high heights. These challenges include insufficient bending and torsional stiffness, excessive self-weight due to large concrete pouring volumes, difficulties in modular assembly, lack of effective local reinforcement in the central region, and difficulties in the coordinated transfer of multi-directional loads through the connection structure. The invention provides a double-steel-tube wind turbine tower structure with locally grouted combined stiffening rings. This structure achieves efficient collaborative work between the two steel tubes by setting locally grouted combined stiffening rings at the ends and center of key stress areas, combined with spatial claw-shaped connectors. This significantly reduces material usage, improves construction efficiency, and enhances structural adaptability while ensuring structural safety. This invention provides a partially grouted combined ring-stiffened double steel pipe wind turbine tower structure, comprising multiple tube segments sequentially spliced ​​along the tower axial direction; Each section of the cylinder is composed of an inner steel plate and an outer steel plate arranged coaxially to form a double-layered closed cavity, with a cavity width ranging from 50 mm to 150 mm. The inner steel plate has a grouting port on its outer surface near the end of the cylinder section; the inner steel plate and the outer steel plate are welded together to an annular end plate, the end plate has reserved bolt holes evenly distributed in the circumferential direction, and the inner side of the end plate has an integrally formed end plate stiffening rib. An internal annular stiffening rib is provided on the inner side of the end plate, between the inner steel plate and the outer steel plate. The internal annular stiffening rib is near the end. The internal annular stiffening rib is a closed annular steel plate. Its inner edge is attached to the outer wall of the inner steel plate and fully welded. Its outer edge is attached to the inner wall of the outer steel plate and fully welded. Studs are welded to the lower surface of the upper inner annular stiffening rib, the upper surface of the lower inner annular stiffening rib, the outer surface of the inner steel plate, and the inner surface of the outer steel plate. Adjacent cylinder sections are fastened together by high-strength bolts through the reserved bolt holes on the end plates. Concrete is then injected into the partially enclosed cavity formed by the inner steel plate, the outer steel plate, and the inner annular stiffening rib through the grouting port of the inner steel plate to form the end-partial grouting combined stiffening ring reinforcement section. Furthermore, a central local grouting combined stiffening ring reinforcement section is set in the middle area of ​​the cylinder section with a height greater than 8m; the central local grouting combined stiffening ring reinforcement section includes two internal annular stiffening ribs arranged in parallel between the inner steel plate and the outer steel plate, with an axial spacing of 200 mm to 600 mm between the two internal annular stiffening ribs; studs are welded on the upper and lower surfaces of the two internal annular stiffening ribs, as well as on the outer surface of the inner steel plate and the inner surface of the outer steel plate between them. Furthermore, an arc-shaped pre-reserved opening is made in the area between the two internal annular stiffening ribs of the inner steel plate, and a post-welded inner steel plate is embedded therein; the post-welded inner steel plate is simultaneously welded and fixed to the inner steel plate and the two internal annular stiffening ribs through continuous full-weld post-weld seams, forming a closed cavity jointly enclosed by the inner steel plate, the post-welded inner steel plate and the two internal annular stiffening ribs; a post-welded inner steel plate grouting port is opened on the post-welded inner steel plate, and concrete is poured into the closed cavity through the grouting port to form a central local grouting combined stiffening ring reinforcement section. Furthermore, in the non-grouting cavity section between the end-part grouting combined stiffening ring reinforcement section and the middle-part grouting combined stiffening ring reinforcement section, multiple claw-shaped connectors are evenly distributed between the inner and outer steel plates; the claw-shaped connectors include a circular steel plate, two bending limbs, two torsion limbs, and three connecting limbs; wherein, one end of the two bending limbs and the two torsion limbs are symmetrically welded to the outer edge of the circular steel plate, and the other end is indirectly connected to the inner surface of the outer steel plate through connecting limb No. 1 and connecting limb No. 2 respectively; one end of connecting limb No. 3 is connected to the central node formed by the intersection of the circular steel plate and the bending limbs and the torsion limbs, and the other end is connected to the intersection of the midpoint of connecting limb No. 1 and connecting limb No. 2. Furthermore, the circular steel plate is fixedly connected to the inner wall of the inner steel plate by a single plug weld opening on the inner steel plate using a through-hole plug weld method. Furthermore, the studs are cylindrical head shear studs with a diameter of 13 mm to 19 mm and a height of 50 mm to 80 mm. They are arranged in a rectangular or quincunx pattern along the outer surface of the inner steel plate, the inner surface of the outer steel plate, and the surface of the internal annular stiffening ribs, with a transverse spacing of 100 mm to 200 mm and a longitudinal spacing of 100 mm to 200 mm. Furthermore, the thickness of the internal annular stiffening rib is 10 mm to 25 mm, and the width is equal to the cavity width between the inner steel plate and the outer steel plate; the thickness of the end plate is 20 mm to 40 mm, the height of the end plate stiffening rib is 50 mm to 100 mm, and the thickness is the same as that of the end plate. Furthermore, the post-welded inner steel plate and the post-welded weld between the inner steel plate and the two internal annular stiffening ribs are continuous full welds, forming a closed cavity structure with one weld and three plates. The beneficial effects of the technical solutions provided in this application include at least the following: This invention achieves continuous bending and shear resistance between adjacent sections by incorporating an end-section locally grouted stiffening ring reinforced with internal annular stiffening ribs, studs, and locally grouted concrete. This avoids abrupt stiffness changes at traditional flange connections. Furthermore, by incorporating a central locally grouted stiffening ring reinforced with two internal annular stiffening ribs, a welded closed cavity with three plates, and locally grouted concrete in the high-stress region of the middle section, this invention effectively suppresses local buckling of the double steel pipes under wind loads, enhancing overall bending stiffness. Finally, by arranging claw-shaped connectors in the non-grouted sections, the invention utilizes their spatial triangular stabilizing framework to simultaneously transmit radial separation forces caused by bending and shear forces caused by torsion. The coordinated sliding force and axial deformation force enable the two steel pipes to share the load synergistically throughout the entire height range. Since concrete grouting is only carried out in the end splicing area and the high-stress area in the middle, while the remaining areas remain in a cavity state, the amount of concrete used is reduced by more than 30% compared with the overall core-filled structure, which significantly reduces the self-weight of the tower and the difficulty of transportation and hoisting. The end stiffening structure is located in the open area at the end of the cylinder section, which facilitates factory welding operations. The middle strengthening structure adopts the post-welded inner steel plate and the "one seam three plates" welding process, which solves the technical problem of simultaneous welding of multiple plates in narrow gaps and achieves the unity of high-precision factory prefabrication and rapid on-site assembly. The height of the cylinder section, the number of middle strengthening sections, the layout density of claw-shaped connectors, and the length of the grouting area can all be parametrically adjusted according to the tower design height (80 m to 160 m), wind load level, and seismic fortification requirements, which has good engineering adaptability and structural scalability. This invention achieves multiple objectives—improved bending and torsional resistance, optimized material usage, simplified construction process, and modular adaptation—without sacrificing structural safety, through the organic integration of local grouting strategy, combined ring stiffening structure, and multi-directional claw connectors. It provides a novel structural system for ultra-high wind turbine towers that can be industrially produced, efficiently assembled on-site, and has superior mechanical properties. Attached Figure Description

[0005] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0006] Figure 1 This is a schematic diagram of the whole invention and a partial cross-sectional view; Figure 2 This is a partial axonometric view of the present invention; Figure 3 This is a cross-sectional view of the end grouting of the present invention; Figure 4 This is a cross-sectional view of the grouting section in the middle of the present invention; Figure 5 This is a cross-sectional view of the claw-shaped connector arrangement of the present invention; Figure 6 This is an isometric view of the claw-shaped connector of the present invention.

[0007] The attached figures are labeled as follows: 1. Tower; 2. Tube section; 3. End plate stiffening rib; 4. Stud; 5. Internal annular stiffening rib; 6. Post-welded inner steel plate; 7. Claw-shaped connector; 8. Concrete; 21. Inner steel plate; 22. Outer steel plate; 23. End plate; 211. Inner steel plate grouting port; 212. Plug weld; 231. Reserved bolt hole; 61. Post-welded inner steel plate grouting port; 71. Bending limb; 72. Torsion limb; 73. Connecting limb; 731. Connecting limb No. 1; 732. Connecting limb No. 2; 733. Connecting limb No. 3; 74. Circular steel plate. Detailed Implementation

[0008] refer to Figures 1 to 6 The locally grouted combined ring-stiffened double-steel-tube wind turbine tower structure described in this invention can be manufactured and installed in actual engineering as follows: The tower 1 is composed of multiple tube segments 2 sequentially spliced ​​vertically. Each tube segment 2 adopts a double-steel-tube structure, including an inner steel plate 21 and an outer steel plate 22 arranged coaxially, forming a closed cavity between them. The cavity width is controlled within the range of 50 mm to 150 mm to balance structural rigidity and construction feasibility. Figure 1 As shown, near the end of the cylinder section 2, an inner steel plate grouting port 211 is provided on the outer surface of the inner steel plate 21 for subsequent concrete 8 pouring; the inner steel plate 21 and the outer steel plate 22 are welded together to an annular end plate 23, which has pre-reserved bolt holes 231 evenly distributed circumferentially on the end plate 23, and an end plate stiffening rib 3 is integrally formed on the inner side of the end plate 23 to enhance the local stiffness and shear resistance of the end area. Figure 3As shown, an internal annular stiffening rib 5 is provided on the inner side of the end plate 23, between the inner steel plate 21 and the outer steel plate 22. The stiffening rib is a closed annular steel plate, with its inner edge attached to and fully welded to the outer wall of the inner steel plate 21, and its outer edge attached to and fully welded to the inner wall of the outer steel plate 22. Studs 4 are welded on the upper and lower surfaces of the internal annular stiffening rib 5, the outer surface of the inner steel plate 21, and the inner surface of the outer steel plate 22. The studs 4 are cylindrical shear studs with a diameter of 13 mm to 19 mm and a height of 50 mm to 80 mm, arranged in a rectangular or quincunx pattern, with a horizontal and vertical spacing of 100 mm to 200 mm to ensure effective anchoring between the concrete 8 and the steel plate. Adjacent cylinder sections 2 are fastened on-site using 10.9 or 12.9 grade high-strength bolts (diameter M24 to M36) through the reserved bolt holes 231 on the end plate 23. Subsequently, C40 to C60 self-compacting micro-expansion concrete 8 is injected into the partially closed cavity formed by the inner steel plate 21, the outer steel plate 22 and the internal annular stiffening rib 5 through the inner steel plate grouting port 211. The injection pressure is controlled at 0.2 MPa to 0.5 MPa until the concrete 8 overflows from the vent hole. After curing for no less than 7 days, a locally grouted combined stiffening ring reinforcement section is formed at the end, thereby providing continuous bending and shear bearing capacity on the basis of mechanical connection, avoiding stress concentration caused by sudden change in stiffness at traditional flange connections. For section 2 of the cylinder with a height greater than 8 m, if there is a large bending moment in the central region or if it is necessary to improve the overall stability, a centrally located locally grouted stiffening ring reinforcement section should be added between the inner steel plate 21 and the outer steel plate 22. For example... Figure 4 As shown, the reinforcing section includes two parallel internal annular stiffening ribs 5, with an axial spacing of 200 mm to 600 mm. Studs 4 are welded to the upper and lower surfaces of the two internal annular stiffening ribs 5, as well as to the outer surface of the inner steel plate 21 and the inner surface of the outer steel plate 22 between them. To solve the problem of difficult welding operations in the narrow cavity, an arc-shaped pre-reserved opening is made in the area between the two internal annular stiffening ribs 5 on the inner steel plate 21, and a post-welded inner steel plate 6 is inserted therein. After the two internal annular stiffening ribs 5 and the outer steel plate 22 are welded together, the post-welded inner steel plate 6 is simultaneously welded and fixed to the inner steel plate 21 and the two internal annular stiffening ribs 5 through a continuous full-welded post-weld, forming a closed cavity structure of "one seam and three plates". A grouting port 61 is provided on the inner steel plate 6 after welding. Concrete 8 is injected into the closed cavity through the grouting port 61 to form a central local grouting combination stiffening ring reinforcement section, which effectively suppresses the local buckling of the double steel pipes under wind load and improves the overall bending stiffness. In the non-grouting cavity section between the end-partially grouted stiffening ring reinforcement section and the middle-partially grouted stiffening ring reinforcement section, multiple claw-shaped connectors 7 are evenly distributed between the inner steel plate 21 and the outer steel plate 22, such as... Figure 5 and Figure 6As shown. The claw-shaped connector 7 includes a circular steel plate 74, two bending limbs 71, two torsion limbs 72, and three connecting limbs 73; wherein, one end of the two bending limbs 71 and the two torsion limbs 72 are symmetrically welded to the outer edge of the circular steel plate 74, and the other end is indirectly connected to the inner surface of the outer steel plate 22 through the first connecting limb 731 and the second connecting limb 732 respectively; one end of the third connecting limb 733 is connected to the central node formed by the intersection of the circular steel plate 74 and the bending limbs 71 and the torsion limbs 72, and the other end is connected to the intersection of the midpoint of the first connecting limb 731 and the second connecting limb 732, thereby forming a spatial triangular stable frame composed of the bending limbs 71, the torsion limbs 72 and the three connecting limbs 73. The circular steel plate 74 is fixedly connected to the inner wall of the inner steel plate 21 by a single plug weld 212 opened on the inner steel plate 21 through a fusion plug weld. This allows the claw-shaped connector 7 to achieve bidirectional connection with the inner steel plate 21 and the outer steel plate 22 by opening only one plug weld 212 on the inner steel plate 21, which simplifies the construction process and enhances the cooperative stress-bearing capacity between the two steel pipes. During the factory prefabrication stage, the inner steel plate 21 and outer steel plate 22 are first rolled and welded to the design height to form the main body of the cylindrical section 2. Then, an inner steel plate grouting port 211 is opened on the outer surface of the inner steel plate 21 at the end of the cylindrical section 2. Annular end plates 23 are welded to the edges of the inner and outer steel plates at the end, and pre-drilled bolt holes 231 are drilled on the end plates 23. Simultaneously, end plate stiffening ribs 3 are welded to the inner side of the end plates 23. Next, internal annular stiffening ribs 5 are installed on the inner side of the end plates 23 and fully welded. Then, studs 4 are welded to the relevant surfaces. For cylindrical sections 2 requiring central reinforcement, an arc-shaped pre-drilled opening is opened at the corresponding position on the inner steel plate 21. Two internal annular stiffening ribs 5 are placed between the inner and outer steel plates and welded to the inner wall of the outer steel plate 22. The relevant surface is welded with studs 4; then the post-welded inner steel plate 6 is embedded into the arc-shaped reserved opening, and it is simultaneously welded to the inner steel plate 21 and the two internal annular stiffening ribs 5 through continuous full-welding post-weld seams to form a closed cavity, and a post-welded inner steel plate grouting port 61 is opened on the post-welded inner steel plate 6; finally, claw-shaped connectors 7 are arranged at the designed interval between the inner and outer steel plates in the non-grouting section, and the circular steel plate 74 is melt-through plug-welded to the inner wall of the inner steel plate 21 through a single plug weld 212 on the inner steel plate 21. Then, the bending limb 71 and the torsion limb 72 are welded to the inner surface of the outer steel plate 22 through the first connecting limb 731 and the second connecting limb 732, and the welding of the third connecting limb 733 is completed to form a spatial triangular stable frame. During the on-site installation phase, the end plates 23 of adjacent cylinder sections 2 are aligned, high-strength bolts are inserted, and pre-tension is applied to complete the mechanical connection. Subsequently, self-compacting micro-expansion concrete 8 is injected into the closed cavities at the ends and middle through the inner steel plate grouting port 211 and the post-welded inner steel plate grouting port 61, until the grout overflows from the vent hole, completing the formation of the local grouting combined stiffening ring. The entire structural system provides load-bearing reinforcement in key areas through the end and middle local grouting combined stiffening ring reinforcement sections, and maintains the overall collaborative working performance of the double steel pipes in non-grouting sections through the claw-shaped connectors 7. This significantly reduces the amount of concrete used (more than 30% less than the overall core-filled structure) while ensuring structural safety, reducing the self-weight of the tower, facilitating transportation and hoisting, and achieving the unification of high-precision factory prefabrication and rapid on-site assembly. In addition, the height of section 2, the number of central reinforcing sections, the density of claw connectors 7, and the length of the grouting zone can all be parametrically adjusted according to the tower design height (80 m to 160 m), wind load level, and seismic fortification requirements, thus possessing good engineering adaptability and structural scalability.

[0009] The above description is merely an optional embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A partially grouted combined ring-stiffened double steel pipe wind turbine tower structure, comprising multiple tube segments (2) sequentially spliced ​​along the axial direction of the tower (1). Each cylinder section (2) is composed of an inner steel plate (21) and an outer steel plate (22) arranged coaxially to form a double-layer closed cavity with a cavity width of 50 mm to 150 mm. The inner steel plate (21) has an inner steel plate grouting port (211) near the end of the cylinder section (2) on its outer surface; the inner steel plate (21) and the outer steel plate (22) are welded together to an annular end plate (23), and the end plate (23) has reserved bolt holes (231) evenly distributed in the circumferential direction, and the inner side of the end plate (23) is integrally formed with end plate stiffening ribs (3); An internal annular stiffening rib (5) is provided on the inner side of the end plate (23) and between the inner steel plate (21) and the outer steel plate (22). The internal annular stiffening rib (5) is a closed annular steel plate. Its inner edge is attached to the outer wall of the inner steel plate (21) and fully welded, and its outer edge is attached to the inner wall of the outer steel plate (22) and fully welded. Studs (4) are welded to the lower surface of the upper inner annular stiffening rib (5), the upper surface of the lower inner annular stiffening rib (5), the outer surface of the inner steel plate (21), and the inner surface of the outer steel plate (22). Adjacent cylinder sections (2) are fastened together by high-strength bolts through the reserved bolt holes (231) on the end plate (23), and concrete (8) is poured into the partially closed cavity formed by the inner steel plate (21), the outer steel plate (22), and the inner annular stiffening rib (5) through the grouting port (211) of the inner steel plate to form the end local grouting combined stiffening ring reinforcement section.

2. The locally grouted combined ring-reinforced double steel pipe wind turbine tower structure according to claim 1, characterized in that, A central local grouting combined stiffening ring reinforcement section is set in the middle area of ​​the cylinder section (2) with a height greater than 8m; the central local grouting combined stiffening ring reinforcement section includes two internal annular stiffening ribs (5) arranged in parallel between the inner steel plate (21) and the outer steel plate (22), and the axial spacing between the two internal annular stiffening ribs (5) is 200 mm to 600 mm; studs (4) are welded on the upper and lower surfaces of the two internal annular stiffening ribs (5), as well as on the outer surface of the inner steel plate (21) and the inner surface of the outer steel plate (22) between them.

3. The locally grouted combined ring-reinforced double steel pipe wind turbine tower structure according to claim 1, characterized in that, An arc-shaped pre-reserved opening is made in the area between the two internal annular stiffening ribs (5) of the inner steel plate (21), and the post-welded inner steel plate (6) is embedded therein; the post-welded inner steel plate (6) is simultaneously welded and fixed to the inner steel plate (21) and the two internal annular stiffening ribs (5) by a continuous full-welded post-weld weld, forming a closed cavity enclosed by the inner steel plate (21), the post-welded inner steel plate (6) and the two internal annular stiffening ribs (5); a post-welded inner steel plate grouting port (61) is opened on the post-welded inner steel plate (6), and concrete (8) is poured into the closed cavity through the grouting port to form a central local grouting combined stiffening ring reinforcement section.

4. The locally grouted combined ring-reinforced double steel pipe wind turbine tower structure according to claim 1, characterized in that, In the non-grouting cavity section between the end local grouting combined stiffening ring reinforcement section and the middle local grouting combined stiffening ring reinforcement section, a plurality of claw-shaped connectors (7) are evenly distributed between the inner steel plate (21) and the outer steel plate (22); the claw-shaped connectors (7) include a circular steel plate (74), two bending limbs (71), two torsion limbs (72) and three connecting limbs (73); wherein, one end of the two bending limbs (71) and the two torsion limbs (72) are symmetrically welded to the outer edge of the circular steel plate (74), and the other end is indirectly connected to the inner surface of the outer steel plate (22) through the first connecting limb (731) and the second connecting limb (732) respectively; one end of the third connecting limb (733) is connected to the central node formed by the intersection of the circular steel plate (74) and the bending limbs (71) and the torsion limbs (72), and the other end is connected to the intersection of the midpoint of the first connecting limb (731) and the second connecting limb (732).

5. The locally grouted combined ring-reinforced double steel pipe wind turbine tower structure according to claim 1, characterized in that, The circular steel plate (74) is fixedly connected to the inner wall of the inner steel plate (21) by a single plug weld (212) opened on the inner steel plate (21) in a through-hole plug weld manner.

6. The locally grouted combined ring-reinforced double steel pipe wind turbine tower structure according to claim 1, characterized in that, The studs (4) are cylindrical head shear studs with a diameter of 13 mm to 19 mm and a height of 50 mm to 80 mm. They are arranged in a rectangular or quincunx pattern along the outer surface of the inner steel plate (21), the inner surface of the outer steel plate (22), and the surface of the internal annular stiffening ribs (5), with a transverse spacing of 100 mm to 200 mm and a longitudinal spacing of 100 mm to 200 mm.

7. The locally grouted combined ring-reinforced double steel pipe wind turbine tower structure according to claim 1, characterized in that, The thickness of the internal annular stiffening rib (5) is 10 mm to 25 mm, and the width is equal to the cavity width between the inner steel plate (21) and the outer steel plate (22); the thickness of the end plate (23) is 20 mm to 40 mm, the height of the end plate stiffening rib (3) is 50 mm to 100 mm, and the thickness is the same as that of the end plate (23).

8. The locally grouted combined ring-reinforced double steel pipe wind turbine tower structure according to claim 1, characterized in that, The post-welded inner steel plate (6) and the inner steel plate (21) and the two internal annular stiffening ribs (5) are continuous full welds, forming a closed cavity structure of "one weld and three plates".

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