An assembled wind power steel tower initial geometric defect reinforcing device

Abstract

An assembled wind power steel tower initial geometric defect reinforcing device, the upper steel cylinder inner ring is composed of the upper steel cylinder inner ring left segment and the upper steel cylinder inner ring right segment, is sleeved on the upper inner wall of the defective tower section, the lower steel cylinder inner ring is composed of the lower steel cylinder inner ring left segment and the lower steel cylinder inner ring right segment, is sleeved on the lower inner wall of the defective tower section, the ring hoop pre-tightening device is provided with two groups, is connected with the end of the upper steel cylinder inner ring left segment and the upper steel cylinder inner ring right segment and the end of the lower steel cylinder inner ring left segment and the lower steel cylinder inner ring right segment respectively, is used for applying radial pre-tightening force to the upper steel cylinder inner ring and the lower steel cylinder inner ring.The utility model discloses two groups of inner rings, each group is composed of left-right symmetrical half rings, accurately matches the actual inner diameter of the defective tower section at the corresponding height, ensures that the inner ring and the tower inner wall form the '' shape follows the actual change '' fit relationship.

Description

Technical Field

[0001] This utility model belongs to the field of wind turbine tower reinforcement technology, specifically a prefabricated wind turbine steel tower initial geometric defect reinforcement device. Background Technology

[0002] As my country's wind power industry rapidly develops towards large-scale and deep-sea applications, the precision requirements for the manufacturing and installation of wind turbine steel towers are increasing. However, in actual engineering projects, due to multiple factors such as steel rolling tolerances, plate forming errors, welding residual stress, and deformation during transportation and hoisting, some tower segments exhibit varying degrees of initial geometric defects at the factory or on-site installation stages. Typical forms include: localized depressions, excessive cross-sectional ellipticity (major axis / minor axis deviation exceeding specification limits), and bulging or irregular wave deformation in the weld area. Although these defects do not immediately lead to structural failure, they weaken the tower's load-bearing capacity. Especially under long-term wind loads, gravitational eccentricity, and dynamic fatigue, they are highly susceptible to inducing local buckling, stress concentration, and even crack initiation, seriously threatening the safe operation of the wind turbine throughout its entire life cycle.

[0003] To address the above problems, existing technologies mainly employ the following methods, but all of them have significant technical drawbacks:

[0004] Firstly, traditional reinforcement methods mostly involve external wrapping or welding reinforcement, which makes it difficult to achieve geometric correction and cannot actively restore the original cross-sectional shape of the tower. Furthermore, there is often a risk of voids, slippage, or bonding failure between the external reinforcement layer and the tower. On the other hand, on-site welding can easily introduce heat-affected zone embrittlement, residual tensile stress, and new weld defects, which can exacerbate fatigue sensitivity and does not conform to the modern wind power operation and maintenance trend of "no hot work and green construction".

[0005] Secondly, existing internal support structures are mostly integral or non-adjustable, resulting in poor adaptability and difficult construction. A few solutions employ built-in rigid rings or support frames, but these typically need to be fitted as a whole from the tower end, making them unsuitable for pre-assembled tower segments. Furthermore, their fixed dimensions make it difficult to match the actual inner diameter, which may exhibit irregular deformation, leading to poor contact and constraint failure. Simultaneously, these structures generally lack pre-tightening adjustment mechanisms, making it impossible to apply targeted reaction forces based on defect morphology, nor can they form an effective friction-bond composite interface. This results in easy loosening and slippage under dynamic loads, leading to insufficient long-term reliability.

[0006] To address this issue, a prefabricated wind turbine steel tower initial geometric defect reinforcement device is provided. Utility Model Content

[0007] In view of the above situation and to overcome the defects of the prior art, this utility model provides a prefabricated wind turbine steel tower initial geometric defect reinforcement device to at least partially solve the above technical problems.

[0008] The technical solution adopted by this utility model is as follows:

[0009] This utility model proposes a device for reinforcing the initial geometric defects of prefabricated wind turbine steel towers, comprising:

[0010] Defective tower section;

[0011] The inner ring of the upper steel cylinder is composed of the left section and the right section of the inner ring of the upper steel cylinder, and is fitted onto the upper inner wall of the defective tower section.

[0012] The lower steel cylinder inner ring hoop is composed of the left section and the right section of the lower steel cylinder inner ring hoop, and is fitted onto the lower inner wall of the defective tower section.

[0013] The ring hoop pre-tightening device is provided in two sets, which are respectively connected to the ends of the left and right sections of the inner ring hoop of the upper steel cylinder and the ends of the left and right sections of the inner ring hoop of the lower steel cylinder, and are used to apply radial pre-tightening force to the inner ring hoop of the upper steel cylinder and the inner ring hoop of the lower steel cylinder.

[0014] Fixed bolt plates are respectively fixed to the outer middle part of the left section of the inner ring hoop of the upper steel cylinder, the right section of the inner ring hoop of the upper steel cylinder, the left section of the inner ring hoop of the lower steel cylinder, and the right section of the inner ring hoop of the lower steel cylinder;

[0015] Multiple stiffening support plates are provided, with one end of each stiffening support plate connected to the corresponding fixing bolt plate by bolts, and the other end connected to the ring hoop pre-tightening device on the corresponding side;

[0016] The inner diameters of the upper and lower steel cylinder inner rings are consistent with the inner diameters of the defective tower section at the corresponding positions, and the upper and lower steel cylinder inner rings form a tight fit with the inner wall of the defective tower section.

[0017] As a further improvement of this utility model: the ring clamp pre-tightening device includes:

[0018] The ring end plates are respectively fixed to the mating end faces of the left and right sections of the inner ring of the upper steel cylinder, and the mating end faces of the left and right sections of the inner ring of the lower steel cylinder.

[0019] The telescopic screw has its two ends screwed into two oppositely arranged ring end plates, which are used to adjust the distance between the two ring segments and apply preload;

[0020] A locking nut is screwed onto the telescopic screw and located outside the ring end plate. It is used to lock the position of the telescopic screw after a predetermined preload is reached.

[0021] As a further embodiment of this utility model: the left and right sections of the inner ring hoop of the upper steel cylinder are symmetrically arranged circumferentially along the defective tower segment, and the two are spliced ​​together in the vertical plane to form a complete ring; the left and right sections of the inner ring hoop of the lower steel cylinder are also symmetrically arranged circumferentially along the defective tower segment, and spliced ​​together in the vertical plane to form a complete ring, and the inner ring hoop of the upper and lower steel cylinders are spaced apart along the axial direction of the defective tower segment.

[0022] As a further embodiment of this utility model: the fixing bolt plate is a rectangular metal plate, one side of which is fixed to the outer surface of the middle part of the left section of the inner ring hoop of the upper steel cylinder, the right section of the inner ring hoop of the upper steel cylinder, the left section of the inner ring hoop of the lower steel cylinder, and the right section of the inner ring hoop of the lower steel cylinder by high-strength bolts, and the other side is provided with bolt holes for connecting the stiffening support plate.

[0023] As a further embodiment of this utility model: the stiffening support plate has an inverted V-shaped structure, with its apex facing the axis of the defective tower segment, and its two inclined sides connected to the corresponding fixing bolt plate and the ring hoop pre-tightening device respectively. Each stiffening support plate is evenly distributed along the circumference of the defective tower segment, and the number is not less than four sets.

[0024] As a further embodiment of this utility model, an adhesive layer is provided between the inner surfaces of the left section of the inner ring hoop of the upper steel cylinder, the right section of the inner ring hoop of the upper steel cylinder, the left section of the inner ring hoop of the lower steel cylinder, and the right section of the inner ring hoop of the lower steel cylinder and the inner wall of the defective tower section.

[0025] As a further embodiment of this utility model: a carbon fiber cloth pad is provided between the inner surface of the stiffening support plate and the inner wall of the defective tower section, and the carbon fiber cloth pad is bidirectionally attached between the stiffening support plate and the inner wall of the tower by an adhesive method.

[0026] Implementing the embodiments of this utility model will have the following beneficial effects:

[0027] This embodiment uses two sets of inner ring hoops, each composed of symmetrical left and right semi-rings, to accurately match the actual inner diameter of the defective tower segment at the corresponding height, ensuring a "shape-follows-the-body" fit between the hoops and the tower's inner wall. Based on this, a hoop pre-tightening device applies a controllable radial pre-tightening force via a telescopic screw, causing the hoops to generate uniform compressive stress on the tower's inner wall, providing outward thrust in locally concave areas, and applying strong constraint along the major axis of the ellipse, forcing the cross-section to gradually return to an approximately circular shape.

[0028] This embodiment uses fixed bolt plates on the outside of the ring hoop, connected to stiffening support plates in an inverted V shape, to form a spatial truss structure with uniform circumferential distribution (no less than four sets) and double-layer arrangement. When the tower is subjected to wind load bending moment, one side of the support plate is under tension and the opposite side is under compression, forming an internal couple to resist the external bending moment; when subjected to torque, the circumferentially distributed support plates work together through the shear force transmission path, significantly improving torsional stiffness; under dynamic vibration, the triangular support plates efficiently dissipate energy through axial tension and compression.

[0029] The above overview is for illustrative purposes only and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features of the present invention will become readily apparent from the accompanying drawings and the following detailed description. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of this application or 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 this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of the structure of the prefabricated wind turbine steel tower initial geometric defect reinforcement device proposed in this embodiment of the utility model;

[0032] Figure 2 This is a schematic diagram of the ring hoop pre-tightening device of the prefabricated wind turbine steel tower initial geometric defect reinforcement device proposed in this embodiment of the utility model;

[0033] Figure 3 This is a schematic diagram of the bonding interface between the stiffening support plate and the inner wall of the tower in the prefabricated wind turbine steel tower initial geometric defect reinforcement device proposed in this embodiment of the utility model.

[0034] In the diagram: 1. Defective tower section; 2. Left section of the inner ring hoop of the upper steel cylinder; 3. Right section of the inner ring hoop of the upper steel cylinder; 4. Ring hoop pre-tightening device; 5. Left section of the inner ring hoop of the lower steel cylinder; 6. Right section of the inner ring hoop of the lower steel cylinder; 7. Epoxy resin coating; 8. Stiffening support plate; 9. Carbon fiber cloth pad; 10. Fixing bolt plate; 11. Ring hoop end plate; 12. Telescopic screw; 13. Locking nut.

[0035] The accompanying drawings are provided to further understand the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the present invention and do not constitute a limitation thereof. Detailed Implementation

[0036] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of this invention. Therefore, the drawings and description are considered exemplary in nature and not restrictive.

[0037] It is important to note that the terms "first," "second," etc., are used only to distinguish between descriptive and positional descriptions, and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, features specified with "first," etc., may explicitly or implicitly include one or more of that feature; similarly, when the quantity of certain features is not limited by words such as "two" or "three," it should be noted that such features also explicitly or implicitly include one or more features.

[0038] In the embodiments of this utility model, unless otherwise explicitly specified and limited, terms such as "installation," "connection," and "fixation" should be interpreted broadly; for example, they can refer to a fixed connection, a detachable connection, or an integral molding; they can refer to a mechanical connection, a direct connection, a welding connection, or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the accompanying drawings and specific circumstances.

[0039] In the description of the embodiments of this utility model, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this utility model.

[0040] like Figures 1 to 3 As shown, a prefabricated wind turbine steel tower initial geometric defect reinforcement device includes: a defective tower segment 1;

[0041] The inner ring of the upper steel cylinder is composed of the left section 2 and the right section 3 of the inner ring of the upper steel cylinder, and is fitted onto the upper inner wall of the defective tower section 1; the inner ring of the lower steel cylinder is composed of the left section 5 and the right section 6 of the inner ring of the lower steel cylinder, and is fitted onto the lower inner wall of the defective tower section 1.

[0042] The ring hoop pre-tightening device 4 is provided in two sets, which are respectively connected to the ends of the left section 2 and the right section 3 of the inner ring hoop of the upper steel cylinder, and the ends of the left section 5 and the right section 6 of the inner ring hoop of the lower steel cylinder, and are used to apply radial pre-tightening force to the inner ring hoop of the upper steel cylinder and the inner ring hoop of the lower steel cylinder.

[0043] The fixing bolt plates 10 are respectively fixed to the outer middle part of the left section 2, right section 3, left section 5, and right section 6 of the inner ring hoop of the upper steel cylinder; multiple stiffening support plates 8 are provided, one end of each stiffening support plate 8 is connected to the corresponding fixing bolt plate 10 by bolts, and the other end is connected to the ring hoop pre-tightening device 4 on the corresponding side; wherein, the inner diameter of the inner ring hoop of the upper steel cylinder and the inner ring hoop of the lower steel cylinder are consistent with the inner diameter of the defective tower section 1 at the corresponding position, and the inner ring hoop of the upper steel cylinder, the inner ring hoop of the lower steel cylinder and the inner wall of the defective tower section 1 form a tight fit structure.

[0044] In a specific application of this utility model embodiment, when local initial geometric defects (such as excessive cross-sectional ellipticity, local depressions, and weld area deformation) occur in the wind turbine steel tower during manufacturing, transportation, or hoisting, these defects can cause the tower to bear asymmetrical loads during service, leading to stress concentration, fatigue cracks, and even structural instability. This device first takes the defective tower segment (i.e., defective tower segment 1) as the object to be reinforced, and sets an upper steel cylinder inner ring hoop and a lower steel cylinder inner ring hoop at the upper and lower ends of the defective area, respectively. The two ring hoops are symmetrically assembled along the circumference of the tower from two segments (i.e., left segment 2 and right segment 3 of the upper steel cylinder inner ring hoop, and left segment 5 and right segment 6 of the lower steel cylinder inner ring hoop). This segmented design not only facilitates on-site assembly in already installed or confined spaces but also avoids the construction difficulties of traditional integral ring hoops that need to be fitted from the end of the tower.

[0045] During assembly, the left and right sections 2 and 3 of the upper steel cylinder inner ring are first attached to the corresponding semi-circular areas of the upper inner wall of the defective tower section 1, respectively. Then, the left and right sections 5 and 6 of the lower steel cylinder inner ring are attached to the lower inner wall. Since the inner diameters of the upper and lower rings strictly match the actual inner diameters of the defective tower section 1 at their respective heights, maximum surface contact can be achieved between the rings and the inner wall of the tower. Subsequently, a ring pre-tightening device 4 is installed at the joint ends of the left and right sections of the ring. The device consists of a ring end plate 11, a telescopic screw 12, and a locking nut 13. By rotating the telescopic screw 12, the relative distance between the left and right ring sections can be adjusted, thereby applying a controllable radial pre-tightening force to the rings. As the pre-tightening force increases, the rings generate uniform radial compressive stress on the inner wall of the tower. On the one hand, the compressive stress forces the local defective area of ​​the tower to recover towards an ideal circle. On the other hand, it establishes a stable friction interface between the rings and the tower, effectively suppressing further deformation or slippage of the defective part under wind load, gravity, and dynamic vibration.

[0046] Meanwhile, fixing bolt plates 10 are fixed on the outer middle part of the upper and lower ring hoops (i.e., the side away from the tower axis). The fixing bolt plates 10 serve as intermediate connection nodes for anchoring the stiffening support plate 8. The stiffening support plate 8 is arranged in an inverted V shape, with its apex facing the central axis of the tower. Its two inclined sides are connected to the structural base of the fixing bolt plates 10 and the ring hoop pre-tightening device 4, respectively. When the tower experiences a slight radial displacement due to external loads, the stiffening support plate 8 will transmit force through axial tension and compression, dispersing the local deformation energy to the entire ring hoop structure. Through the synergistic effect between the upper and lower ring hoops, longitudinal constraint stiffness is formed, thereby improving the overall bending and torsional resistance of the defect area.

[0047] Meanwhile, the inner side of the stiffening support plate 8 (i.e. the side facing the inner wall of the tower) does not directly contact the tower. Instead, a carbon fiber cloth pad 9 is placed between them. The pad is made using a two-way bonding process, which ensures good adhesion to the stiffening support plate 8 and the inner wall of the tower. Due to its high elastic modulus and low Poisson's ratio, it can play a "flexible transition" role in the local stress concentration area, avoiding secondary damage caused by the rigid support directly pressing the thin-walled structure of the tower.

[0048] In addition, an epoxy resin coating 7 is pre-coated on the entire contact surface between the ring hoop and the inner wall of the tower. The coating not only provides strong adhesion, making the ring hoop and the tower form a "composite material-like" integral load-bearing unit, but also fills the micro-uneven gaps, improves the contact density, prevents moisture and corrosive media from entering the interface, and extends the service life of the device.

[0049] In one specific embodiment, the ring hoop pre-tightening device 4 includes: ring hoop end plates 11 respectively fixed to the mating end faces of the left section 2 and the right section 3 of the inner ring hoop of the upper steel cylinder, and the mating end faces of the left section 5 and the right section 6 of the inner ring hoop of the lower steel cylinder; the two ends of the telescopic screw 12 are respectively screwed into the two oppositely arranged ring hoop end plates 11 for adjusting the distance between the two ring hoop sections and applying pre-tightening force; the locking nut 13 is screwed onto the telescopic screw 12 and located outside the ring hoop end plates 11 for locking the position of the telescopic screw 12 after the predetermined pre-tightening force is reached.

[0050] The left section 2 and the right section 3 of the inner ring hoop of the upper steel cylinder are symmetrically arranged around the defective tower segment 1, and the two are spliced ​​together in the vertical plane to form a complete ring; the left section 5 and the right section 6 of the inner ring hoop of the lower steel cylinder are also symmetrically arranged around the defective tower segment 1, and spliced ​​together in the vertical plane to form a complete ring. The inner ring hoop of the upper steel cylinder and the inner ring hoop of the lower steel cylinder are spaced apart along the axial direction of the defective tower segment 1.

[0051] In a specific application of this utility model embodiment, the device first sets up an inner ring hoop structure composed of left and right sections at the upper and lower parts of the defect area. The upper steel cylinder inner ring hoop is symmetrically arranged by the left section 2 and the right section 3 along the circumference of the tower, and they are joined together in the vertical plane to form a complete ring. The lower steel cylinder inner ring hoop is spliced ​​by the left section 5 and the right section 6 in the same way. The symmetrical segmentation not only facilitates installation from inside the tower (without disassembling the tower or fitting it from the end), but also ensures the uniform transmission of preload in the ring direction, avoiding eccentric loading or local warping caused by unilateral force.

[0052] After the initial positioning of the ring sections is completed, ring end plates 11 are pre-fixed on the left and right mating surfaces of each ring set. The end plates serve as rigid bases for force transmission and form an adjustable connection pair with the telescopic screw 12. The two ends of the telescopic screw 12 are screwed into the two oppositely arranged ring end plates 11, and the direction of its threads allows the left and right ring sections to be pulled closer or pushed further apart simultaneously when the screw is rotated. By rotating the telescopic screw 12 with a special tool (such as a torque wrench or hydraulic tensioner), the operator can accurately control the slight shrinkage of the ring diameter, thereby applying a controllable radial preload to the inner wall of the tower. As the preload gradually increases, the tower wall surface, which originally had geometric deviations, is "clamped" by the rings, and the locally concave areas are subjected to reverse compressive stress and tend to restore the ideal circular profile, while the stiffness of the entire cross-section is improved.

[0053] Once the preload reaches the value (which can be determined by torque, preload relationship, or strain monitoring), immediately tighten the locking nut 13 at the position of the telescopic screw 12 outside the ring end plate 11. The locking nut not only prevents loosening, but also "freezes" the tension state of the telescopic screw 12 at the current position through axial compression between it and the end plate, preventing the preload from decaying due to vibration, temperature changes, or material creep.

[0054] Furthermore, the upper and lower sets of inner ring hoops do not work in isolation, but are arranged at intervals along the axial direction of the defective tower segment 1, forming a "double hoop clamping" structure. The axially separated layout allows the device to not only constrain the deformation of a single section, but also effectively suppress the bending or torsional deformation tendency of the defective area along the height of the tower. When the tower undergoes slight deflection under wind load, the upper and lower ring hoops form a pair of opposite bending moments through their respective radial constraint forces, improving the local bending stiffness; while under torque, the shear force transmission path between the two ring hoops is also strengthened, enhancing torsional stability.

[0055] Furthermore, since both the upper and lower rings adopt a completely symmetrical left-right segmented form and are spliced ​​in the vertical plane, the entire structure has a high degree of axial symmetry and balance in mechanics. This not only avoids the introduction of new eccentric loads due to asymmetrical installation, but also ensures that the preload is evenly distributed in the 360° circumferential range, maximizing the load-bearing potential of the steel while reducing the risk of local stress concentration.

[0056] In one specific embodiment, the fixing bolt plate 10 is a rectangular metal plate. One side of the plate is fixed to the outer surface of the middle part of the left section 2, right section 3, left section 5, and right section 6 of the inner ring hoop of the upper steel cylinder, respectively, by high-strength bolts. The other side is provided with bolt holes for connecting the stiffening support plate 8. The stiffening support plate 8 has an inverted V-shaped structure, with its apex facing the axis of the defective tower segment 1. The two inclined sides are connected to the corresponding fixing bolt plate 10 and the ring hoop pre-tightening device 4, respectively. Each stiffening support plate 8 is evenly distributed around the circumference of the defective tower segment 1, and the number is not less than four sets.

[0057] In a specific application of this utility model embodiment, after the inner ring hoops of the upper and lower steel cylinders are radially tightened to the inner wall of the defective tower section 1 by the ring hoop pre-tightening device 4, although the local cross-section of the tower has initially restored its geometric shape and obtained basic constraints, it still needs to cope with the bending moment and torque caused by wind loads, as well as the dynamic disturbances caused by the self-weight and eccentric mass of the tower in actual operation. At this time, the rectangular metal plate is firmly anchored to the outer surface of the ring hoop by high-strength bolts to ensure that it is located in the area where the ring hoop is subjected to the most uniform force and the deformation is minimal, thereby providing a stable and reliable support point for subsequent connections. The outer side of each fixing bolt plate 10 is provided with a standardized bolt hole array for quick assembly with the stiffening support plate 8.

[0058] Specifically, the stiffening support plate 8 adopts an inverted V-shaped structure, with its apex facing the central axis of the tower. The two inclined sides are respectively connected to the structural base of the fixing bolt plate 10 and the ring hoop pre-tightening device 4 (usually integrated into the ring hoop end plate 11 or its reinforcing ribs), making each set of stiffening support plates 8 essentially a triangular unit with the tower axis as its axis of symmetry. When the tower experiences a slight radial displacement due to external excitation, the triangular unit immediately responds through axial tension and compression. If the tower bulges outward locally, the support plate is compressed; if it concaves inward, the support plate is tensile. Due to the tensile and compressive strength of steel, this axial force transmission mode can efficiently transfer local deformation energy along the inclined sides to the ring hoop body and pre-tightening device, and then react on the tower wall through the friction interface and adhesive layer between the ring hoop and the tower, forming a closed-loop feedback constraint.

[0059] Meanwhile, all stiffening support plates 8 are evenly distributed along the circumference of the tower, with no fewer than four sets, typically arranged at 90° intervals, thus constructing a complete spatial support network within a 360° range. The circumferentially symmetrical layout ensures that regardless of wind direction or load application direction, one or more sets of support plates are always under effective stress, avoiding weak points. Simultaneously, the upper and lower ring hoops each have independent support structures, forming a "double-layer truss" structure in the vertical direction. This not only enhances axial stiffness but also effectively suppresses local buckling or shear deformation of the tower in defect areas. When the tower is subjected to bending moment, one support plate is under tension and the opposite side under compression, forming an internal couple to resist the external bending moment; when subjected to torque, the circumferentially distributed support plates work together to resist torsional deformation through shear force transmission paths.

[0060] In one specific embodiment, an adhesive layer is provided between the inner surfaces of the left section 2, right section 3, left section 5, and right section 6 of the upper steel cylinder inner ring hoop and the inner wall of the defective tower section 1. A carbon fiber cloth pad 9 is provided between the inner surface of the stiffening support plate 8 and the inner wall of the defective tower section 1, and the carbon fiber cloth pad 9 is bidirectionally attached to the stiffening support plate 8 and the inner wall of the tower by an adhesive method.

[0061] In a specific application of this utility model embodiment, when the upper and lower segmented inner ring clamps apply radial clamping force to the defective tower segment 1 through the pre-tightening device, the adhesive layer formed between the inner surface of the ring clamps and the inner wall of the tower immediately takes effect. The adhesive layer is composed of a high-performance epoxy resin coating 7, which has high shear strength, low shrinkage rate, and excellent aging resistance. Under the action of pre-tightening force, the epoxy resin is uniformly squeezed and filled in the microscopic uneven gap between the ring clamps and the tower, forming a continuous and dense adhesive interface. This not only increases the friction coefficient between the two, preventing relative slippage under wind vibration or temperature cycling, but also transforms the local pressure that was originally transmitted only by mechanical contact into a composite force transmission mode in which the adhesive shear force and normal pressure work together in a globally distributed manner.

[0062] Meanwhile, the carbon fiber cloth pad 9, installed between the stiffening support plate 8 and the inner wall of the tower, is designed with the stiffening support plate 8 in an inverted V-shape. Since the apex of the stiffening support plate 8 is close to the inner wall of the tower, direct rigid contact during extreme conditions or minor unexpected deformation of the tower could easily lead to localized crushing or buckling of the thin-walled tower. Therefore, the carbon fiber cloth pad 9 is bidirectionally bonded between the inner side of the support plate and the inner wall of the tower, forming an intermediate medium that combines high tensile strength with moderate compressive elasticity. The carbon fiber cloth itself has extremely high specific strength and modulus, effectively bearing tensile stress along the fiber direction; its fabric structure also possesses a certain degree of compressive resilience in the vertical direction, forming a "controllable buffer zone" between the support plate and the tower. When the tower partially bulges outward and contacts the carbon fiber cloth pad 9, the pad first absorbs some displacement through elastic deformation, avoiding rigid impact. If the deformation continues to increase, the carbon fiber cloth participates in bearing the stress through its high tensile strength, diffusing the localized tensile stress circumferentially and preventing crack initiation.

[0063] Furthermore, the carbon fiber cloth pad 9 and the epoxy adhesive layer are spatially connected and mechanically complementary: the epoxy layer mainly covers the large contact area between the ring hoop and the tower, providing overall bonding and sealing; while the carbon fiber cloth focuses on the high stress-sensitive area near the top of the support plate, providing local reinforcement and energy dissipation.

[0064] In one specific embodiment, the left section 2 and right section 3 of the upper steel cylinder inner ring hoop, as well as the left section 5 and right section 6 of the lower steel cylinder inner ring hoop, are all mechanically spliced ​​without welding. All connection parts are detachably fastened by the ring hoop pre-tightening device 4. The defective tower segment 1 is a wind turbine steel tower segment with initial geometric defects, the forms of which include, but are not limited to, local depressions, ellipticity deviations, or weld deformations. The upper and lower steel cylinder inner ring hoops apply radial pre-tightening forces to form constraint reaction forces on the defective tower segment 1, so as to restore its cross-sectional geometry and improve structural stiffness.

[0065] In the specific application of this utility model embodiment, both the upper and lower sets of ring hoops are composed of two left and right half-ring segments, which are joined together along the vertical plane inside the tower to form a complete ring. The left and right ring segments are mechanically locked together by a ring hoop pre-tightening device 4 arranged at the joint end. During installation, the operator first places the left and right ring segments into the upper and lower ends of the defect area respectively, so that their inner contours closely fit the actual geometry of the tower inner wall (even if there is deformation). Then, by rotating the telescopic screw 12 in the pre-tightening device, the left and right ring segments are gradually pulled closer, so that the ring hoop diameter is controlled to shrink. As the shrinkage increases, the ring hoop applies a continuously increasing radial compressive stress to the tower inner wall. The compressive stress is not uniformly distributed on the ideal circular cross-section, but is adaptively adjusted according to the actual defect shape of the tower. In the concave area, the ring hoop provides outward supporting reaction force, pushing the steel plate to spring back; in the convex or elliptical major axis direction, the ring hoop inhibits further expansion through stronger constraint.

[0066] Specifically, the radial preload not only achieves geometric correction but also enhances the local structural stiffness of the tower. Areas that were originally weak due to defects are transformed into composite sections with high constraint stiffness under the wrapping and compression of the rings. The rings themselves, as high-strength steel components, bear part of the external bending moment and shear force; while the friction interface between the tower and the rings, along with the subsequent bonding layer (though not emphasized here, it is part of the overall structure), jointly transmit shear force, enabling them to work synergistically.

[0067] Since all connections are detachably fastened through pre-tightening devices, the entire reinforcement process is completely reversible. If the tower needs to be replaced, inspected, or the equipment needs to be upgraded or maintained in the future, the ring can be removed in sections simply by loosening the locking nut 13 and releasing the pre-tightening force, without causing any damage to the original tower.

[0068] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0069] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

[0070] The present invention and its embodiments have been described above. This description is not restrictive, and the accompanying drawings are only one embodiment of the present invention; the actual structure is not limited thereto. In conclusion, if those skilled in the art are inspired by this description and design similar structures and embodiments without departing from the inventive spirit of the present invention, such designs should fall within the protection scope of the present invention.

Claims

1. A device for reinforcing initial geometric defects in prefabricated wind turbine steel towers, characterized in that, include: Defective tower segment (1); The inner ring of the upper steel cylinder is composed of the left section (2) and the right section (3) of the inner ring of the upper steel cylinder, and is fitted onto the upper inner wall of the defective tower section (1). The lower steel cylinder inner ring hoop is composed of the left section (5) and the right section (6) of the lower steel cylinder inner ring hoop, and is fitted onto the lower inner wall of the defective tower section (1); The ring hoop pre-tightening device (4) is provided in two sets, which are respectively connected to the ends of the left section (2) of the inner ring hoop of the upper steel cylinder and the right section (3) of the inner ring hoop of the upper steel cylinder, and the ends of the left section (5) of the inner ring hoop of the lower steel cylinder and the right section (6) of the inner ring hoop of the lower steel cylinder, and are used to apply radial pre-tightening force to the inner ring hoop of the upper steel cylinder and the inner ring hoop of the lower steel cylinder; Fixed bolt plates (10) are respectively fixed to the outer side of the middle part of the left section (2) of the inner ring hoop of the upper steel cylinder, the right section (3) of the inner ring hoop of the upper steel cylinder, the left section (5) of the inner ring hoop of the lower steel cylinder and the right section (6) of the inner ring hoop of the lower steel cylinder; Multiple stiffening support plates (8) are provided. One end of each stiffening support plate (8) is connected to the corresponding fixing bolt plate (10) by bolts, and the other end is connected to the ring hoop pre-tightening device (4) on the corresponding side. The inner diameters of the upper steel cylinder inner ring and the lower steel cylinder inner ring are respectively consistent with the inner diameter of the defective tower section (1) at the corresponding position, and the upper steel cylinder inner ring and the lower steel cylinder inner ring form a tight fit structure with the inner wall of the defective tower section (1).

2. The prefabricated wind turbine steel tower initial geometric defect reinforcement device according to claim 1, characterized in that, The ring clamp pre-tightening device (4) includes: The ring end plate (11) is fixed to the mating end face of the left section (2) of the inner ring of the upper steel cylinder and the right section (3) of the inner ring of the upper steel cylinder, and the mating end face of the left section (5) of the inner ring of the lower steel cylinder and the right section (6) of the inner ring of the lower steel cylinder, respectively. The telescopic screw (12) is screwed into two oppositely arranged ring end plates (11) at both ends to adjust the distance between the two ring segments and apply preload. A locking nut (13) is screwed onto the telescopic screw (12) and located outside the ring end plate (11) to lock the position of the telescopic screw (12) after a predetermined preload is reached.

3. The prefabricated wind turbine steel tower initial geometric defect reinforcement device according to claim 1, characterized in that, The left section (2) and right section (3) of the inner ring of the upper steel cylinder are symmetrically arranged around the defective tower segment (1) and are spliced ​​together in the vertical plane to form a complete ring. The left section (5) and right section (6) of the inner ring of the lower steel cylinder are also symmetrically arranged around the defective tower segment (1) and are spliced ​​together in the vertical plane to form a complete ring. The inner ring of the upper steel cylinder and the inner ring of the lower steel cylinder are spaced apart along the axial direction of the defective tower segment (1).

4. The prefabricated wind turbine steel tower initial geometric defect reinforcement device according to claim 1, characterized in that, The fixing bolt plate (10) is a rectangular metal plate. One side of it is fixed to the outer surface of the middle part of the left section (2), right section (3), left section (5), and right section (6) of the inner ring of the upper steel cylinder by high-strength bolts. The other side is provided with bolt holes for connecting the stiffening support plate (8).

5. The prefabricated wind turbine steel tower initial geometric defect reinforcement device according to claim 1, characterized in that, The stiffening support plate (8) has an inverted V-shaped structure, with its apex facing the axis of the defective tower segment (1). The two inclined sides are connected to the corresponding fixing bolt plate (10) and the ring hoop pre-tightening device (4) respectively. Each stiffening support plate (8) is evenly distributed along the circumference of the defective tower segment (1), and the number is not less than four sets.

6. The prefabricated wind turbine steel tower initial geometric defect reinforcement device according to claim 1, characterized in that, An adhesive layer is provided between the inner surfaces of the left section (2) of the inner ring of the upper steel cylinder, the right section (3) of the inner ring of the upper steel cylinder, the left section (5) of the inner ring of the lower steel cylinder and the right section (6) of the inner ring of the lower steel cylinder and the inner wall of the defective tower section (1).

7. The prefabricated wind turbine steel tower initial geometric defect reinforcement device according to claim 1, characterized in that, A carbon fiber pad (9) is provided between the inner surface of the stiffening support plate (8) and the inner wall of the defective tower section (1). The carbon fiber pad (9) is attached to the stiffening support plate (8) and the inner wall of the tower by means of bonding.

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