Lattice type tower connecting structure and wind power tower

Abstract

The invention relates to the technical field of wind power equipment, in particular to a lattice type tower connecting structure and a wind power tower, comprising a corner post, and two or more upper gusset plates and two or more lower gusset plates which are respectively connected to the upper end and the lower end of the corner post; the upper gusset plate and the lower gusset plate are each provided with a first installation hole used for fixing an inclined strut, and at least one of the upper gusset plate and the lower gusset plate is provided with a second installation hole used for fixing a transverse strut. A first ring rib is connected between the adjacent upper gusset plates at the upper end of the corner column, a second ring rib is connected between the adjacent lower gusset plates at the lower end of the corner column, and the inner sides of the first ring rib and the second ring rib are connected with the outer side of the corner column. The device has the advantages of being reasonable in structural design, high in stability, assembled in construction and easy and convenient to install and operate.

Description

Technical Field

[0001] This invention relates to the field of wind power equipment technology, specifically to a lattice tower connection structure and a wind power tower. Background Technology

[0002] In the field of large-scale wind power generation, in order to capture more wind energy, the single unit capacity of wind turbines continues to increase, and the corresponding tower height and load-bearing requirements are greatly increased. Traditional tower structures are gradually becoming unable to meet the comprehensive requirements of current projects for lightweight, high strength, low cost and rapid construction.

[0003] Prestressed hollow-core steel-concrete lattice towers are gaining attention due to their unique structural advantages. Through rational structural design, this type of tower can effectively reduce the load on the tower tube, decrease material usage, lower project costs, streamline construction procedures and processes, reduce labor requirements, significantly shorten installation time, and thus reduce hoisting costs, perfectly aligning with the current development needs of the wind turbine engineering field. However, the connection nodes of the tower, as key load-bearing components of the entire lattice tower structure, are subject to extremely complex stress states. They must not only withstand the weight of the tower itself but also resist various external forces such as wind loads, seismic loads, and dynamic loads during operation. Traditional tower connection node designs often suffer from insufficient structural rationality, poor stability, low prefabrication levels, or cumbersome installation operations, making it difficult to fully utilize the overall performance advantages of prestressed hollow-core steel-concrete lattice towers, and may even become weak links affecting the safety and service life of the entire tower structure. Summary of the Invention

[0004] The purpose of this invention is to provide a connection structure for a lattice tower and a wind power tower, which has the advantages of reasonable structural design, high stability, modular construction, and simple installation and operation.

[0005] 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 connection structure for a lattice tower, comprising a corner column and two or more upper node plates and two or more lower node plates respectively connected to the upper and lower ends of the corner column; each of the upper node plate and the lower node plate is provided with a first mounting hole for fixing diagonal bracing, and at least one of the upper node plate and the lower node plate is provided with a second mounting hole for fixing cross bracing; a first ring rib is connected between adjacent upper node plates at the upper end of the corner column, and a second ring rib is connected between adjacent lower node plates at the lower end of the corner column, wherein the inner sides of the first ring rib and the second ring rib are connected to the outer side of the corner column.

[0006] Furthermore, the corner column includes an outer steel pipe, an inner steel pipe, and a layer of concrete filled between the outer steel pipe and the inner steel pipe. Multiple corner columns are sequentially fixedly connected to form a column body, and prestress is applied to the column body through prestressing tendons arranged in the hollow channel of the inner steel pipe.

[0007] Furthermore, the upper and lower ends of the outer steel pipe are provided with through holes for the upper node plate and the lower node plate to pass through. The inner end of the upper node plate or the lower node plate passes through the through hole and is fixedly connected to the outer wall of the inner steel pipe.

[0008] Furthermore, multiple internal stiffening plates are connected between the outer steel pipe and the inner steel pipe, and these internal stiffening plates are evenly distributed around the outer periphery of the inner steel pipe.

[0009] Furthermore, flanges are fixedly connected to the upper and lower ends of the corner column, and flange stiffening plates are fixed between the flanges and the outer wall of the corner column. The flanges are provided with third mounting holes at the positions between adjacent flange stiffening plates. Fastening bolts are passed through the third mounting holes on the two flanges that abut against each other and connected with nuts to realize the fixed connection of adjacent corner columns.

[0010] Furthermore, the diagonal brace includes a diagonal brace steel pipe and an insert plate connected to the end of the diagonal brace steel pipe; It also includes connecting plates, one end of which is connected to an upper node plate or a lower node plate through a first mounting hole, and the upper node plate or the lower node plate is sandwiched between the two connecting plates; the other end of the two connecting plates is provided with a fourth mounting hole for fixed connection with the insert plate, and the insert plate is located between the two connecting plates.

[0011] Furthermore, there are four first mounting holes and four fourth mounting holes, and the four first mounting holes or the four fourth mounting holes are arranged in a rectangular pattern.

[0012] Furthermore, the cross brace includes a cross brace steel pipe and a channel steel connected to the end of the cross brace steel pipe, and the free end of the channel steel is fixedly connected to the second mounting hole.

[0013] Furthermore, the two ends of the first ring rib are welded and fixed to the upper node plate, and the inner side of the first ring rib is welded and fixed to the outer side of the corner post; the two ends of the second ring rib are welded and fixed to the lower node plate, and the inner side of the second ring rib is welded and fixed to the outer side of the corner post.

[0014] Secondly, the present invention provides a wind turbine tower, which includes the connection structure of the lattice tower described above.

[0015] The present invention has the following unexpected beneficial effects: 1. The upper and lower node plates of the lattice-type tower connection structure of the present invention are located on planes that pass through the axis of the corner column. The upper and lower node plates are provided with first mounting holes for fixing diagonal braces, and at least one is provided with a second mounting hole for fixing cross braces. This allows the diagonal braces, cross braces, and corner column to form an organic whole. The load can be effectively transferred to the corner column through the diagonal braces and cross braces, and then from the corner column to the foundation. The force transmission path is clear, and the bearing capacity of each component can be fully utilized. A first ring rib connects adjacent upper node plates at the upper end of the corner column, and a second ring rib connects adjacent lower node plates at the lower end. The inner sides of the first and second ring ribs are connected to the outer side of the corner column. The first and second ring ribs can enhance the connection stiffness between the node plates, improve the local stability of the corner column at the node, and effectively resist deformation and damage that may occur under external forces.

[0016] 2. The lattice structure itself possesses a large moment of inertia and torsional stiffness. This invention, through the rational arrangement of diagonal braces, horizontal braces, and corner columns, can effectively resist horizontal loads such as wind loads and seismic loads, as well as vertical loads, ensuring the tower maintains a stable working state under various operating conditions. Simultaneously, the inclusion of the first and second ring ribs further enhances the overall stability of the tower. The ring ribs can constrain the lateral deformation of the corner columns, increase the tower's horizontal stiffness, and reduce the vibration amplitude of the tower under wind loads, thereby improving the tower's wind resistance and seismic performance.

[0017] 3. The components of this invention, such as the upper node plate, lower node plate, diagonal brace, and horizontal brace, can be prefabricated in a factory and then transported to the construction site for assembly construction. This reduces on-site wet work and construction difficulty, improves construction efficiency, and shortens the construction cycle. The upper and lower node plates are provided with mounting holes, and the diagonal brace and horizontal brace are installed and fixed to the node plates using bolts and other connecting parts. The installation process is simple and convenient, requiring no complex construction techniques or equipment, thus reducing construction costs and risks. Attached Figure Description

[0018] 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.

[0019] Figure 1 A schematic diagram of the connection structure of the lattice tower described in this invention is shown.

[0020] Figure 2 A top view of the connection structure of the lattice tower described in this invention is shown.

[0021] In the diagram, 1—corner post, 11—outer steel pipe, 12—inner steel pipe, 13—interlayer concrete, 14—inner stiffening plate, 15—flange, 16—flange stiffening plate, 17—third mounting hole; 2—Upper node plate; 3—Lower node plate; 4—Diagonal brace, 41—First mounting hole, 42—Diagonal brace steel pipe, 43—Insertion plate; 5—Horizontal brace, 51—Second mounting hole, 52—Horizontal brace steel pipe, 53—Channel steel; 6—First ring rib, 7—Second ring rib, 8—Connecting plate, 81—Fourth mounting hole, 9—Prestressed tendon. Detailed Implementation

[0022] 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.

[0023] 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.

[0024] In one embodiment, see Figure 1 and Figure 2 As shown, this invention discloses a connection structure for a lattice-type tower, including a corner column 1 and two or more upper node plates 2 and two or more lower node plates 3 respectively connected to the upper and lower ends of the corner column 1. Both the upper node plates 2 and lower node plates 3 are provided with first mounting holes 41 for fixing diagonal braces 4, and at least one of the upper node plates 2 and lower node plates 3 is provided with a second mounting hole 51 for fixing cross braces 5. A first ring rib 6 connects adjacent upper node plates 2 at the upper end of the corner column 1, and a second ring rib 7 connects adjacent lower node plates 3 at the lower end of the corner column 1. The inner sides of the first ring rib 6 and the second ring rib 7 are connected to the outer side of the corner column 1.

[0025] The upper node plate 2 and lower node plate 3 of this invention are provided with first mounting holes 41 for fixing diagonal braces 4, and at least one second mounting hole 51 for fixing cross braces 5. This allows the diagonal braces 4, cross braces 5, and corner column 1 to form an organic whole. The load can be effectively transferred to the corner column 1 through the diagonal braces 4 and cross braces 5, and then transferred from the corner column 1 to the foundation. The force transmission path is clear, and the bearing capacity of each component can be fully utilized. A first ring rib 6 connects the upper node plates 2 adjacent to each other at the upper end of the corner column 1, and a second ring rib 7 connects the lower node plates 3 adjacent to each other at the lower end. The inner sides of the first ring rib 6 and the second ring rib 7 are connected to the outer side of the corner column 1. The first ring rib 6 and the second ring rib 7 can enhance the connection stiffness between adjacent upper node plates 2 or adjacent lower node plates 3, improve the local stability of the corner column 1 at the node, and effectively resist deformation and damage that may occur under external forces.

[0026] The lattice structure itself possesses a large moment of inertia and torsional stiffness. This invention, through the rational arrangement of diagonal braces 4, horizontal braces 5, and corner columns 1, can effectively resist horizontal loads such as wind loads and seismic loads, as well as vertical loads, ensuring the tower maintains a stable working state under various operating conditions. Simultaneously, the placement of the first ring rib 6 and the second ring rib 7 further enhances the overall stability of the tower. The first ring rib 6 and the second ring rib 7 can constrain the lateral deformation of the corner columns, enhance the tower's horizontal stiffness, and reduce the vibration amplitude of the tower under wind loads, thereby improving the tower's wind and seismic resistance. Furthermore, the length of the horizontal brace 4 and the angle and length of the diagonal brace 5 can be adjusted according to the spacing of the corner columns 1 in the lattice section, improving flexibility.

[0027] The components of this invention, such as the upper node plate 2, lower node plate 3, diagonal brace 4, and horizontal brace 5, can be prefabricated in a factory and then transported to the construction site for assembly construction. This reduces on-site wet work and construction difficulty, improves construction efficiency, and shortens the construction cycle. The upper and lower node plates 2 and 3 are provided with mounting holes, and the diagonal brace 4 and horizontal brace 5 are installed and fixed to the node plates using bolts and other connecting parts. The installation process is simple and convenient, requiring no complex construction techniques or equipment, thus reducing construction costs and risks.

[0028] For example, there are two upper node plates 2 and two lower node plates 3. The two upper node plates 2 are located in the plane where the corner column axis and the left and right adjacent corner column axes are respectively located. Similarly, the two lower node plates 3 are located in the plane where the corner column axis and the left and right adjacent corner column axes are respectively located.

[0029] As a preferred embodiment of the present invention, see Figure 2As shown, the corner column 1 includes an outer steel pipe 11, an inner steel pipe 12, and a sandwich concrete 13 filled between the outer steel pipe 11 and the inner steel pipe 12. Multiple corner columns 1 are fixedly connected in sequence to form a column body. Prestress is applied to the column body through prestressed tendons 9 arranged in the hollow channel of the inner steel pipe 12.

[0030] In this preferred embodiment, the outer steel pipe 11, inner steel pipe 12, and sandwiched concrete 13 form a steel-concrete composite structure, leveraging the advantages of their respective materials. The outer steel pipe 11, by constraining the sandwiched concrete 13, limits its lateral expansion under pressure, significantly improving the compressive strength and ductility of the concrete. Simultaneously, the sandwiched concrete 13 fills the internal voids of the outer steel pipe 11, preventing damage due to local instability and also bearing some vertical loads, reducing the stress on the steel pipe. The addition of the inner steel pipe 12 further optimizes the moment of inertia of the section, enhancing the torsional stiffness and bending resistance of the corner column, making it particularly suitable for lattice towers that need to withstand horizontal forces such as wind and seismic loads, effectively reducing lateral deformation of the corner column. Compared to a single steel pipe or pure concrete column, this composite structure significantly improves the overall load-bearing capacity in terms of compression, torsion, and lateral displacement, adapting to the design requirements of taller and heavier towers.

[0031] Furthermore, the outer steel pipe 11 can directly serve as the outer protective shell of the corner column 1, preventing the internal sandwich concrete 13 from directly contacting external rainwater, moisture, and corrosive media, thus reducing problems such as concrete carbonation and steel bar corrosion. The inner steel pipe 12 can protect the prestressed tendons 9 inside, preventing them from failing due to environmental erosion and extending the service life of the entire column. It is especially suitable for tower applications in outdoor, high-altitude, or humid / corrosive environments (such as seaside or industrial areas), reducing the frequency and cost of later maintenance.

[0032] After multiple corner columns 1 are sequentially fixed and connected to form a column, prestressed tendons 9 are arranged and prestressed through the hollow channels of the inner steel pipe 12. This arrangement serves two purposes: firstly, it offsets some of the load stress, improving crack resistance; the prestress applied by the prestressed tendons 9 offsets the tensile stress generated in the column under vertical loads (such as the self-weight of the tower and the weight of the equipment), preventing cracks in the concrete (especially the interlayer concrete 13) due to tension, ensuring that the column is always under predominantly compressive stress, and maintaining structural integrity. Secondly, it enhances the reliability of the corner column connection nodes. The prestressing tightly pulls the sequentially connected corner columns together, reducing the gaps between adjacent corner column connections, making the entire column a more uniformly stressed whole, avoiding local stress concentration caused by loose nodes, and further improving the overall stability of the tower.

[0033] The hollow channel of the inner steel pipe 12 provides an internal construction channel for the arrangement and tensioning of the prestressing tendons 9, eliminating the need for additional slotting or pre-drilling holes on the outside of the corner column 1, thus avoiding damage to the cross-sectional integrity of the corner column. In addition, the corner column 1 can be prefabricated in the factory, including steel pipe welding and concrete pouring. On-site, only the splicing of the corner column 1 and prestressing tensioning need to be completed, further shortening the on-site construction cycle.

[0034] As the core vertical load-bearing component of the tower, the corner column 1's high load-bearing capacity and high stiffness ensure that the loads transmitted by the diagonal brace 4 and the horizontal brace 5 can be stably transferred to the foundation through the gusset plate. The integrity of the prestressed column and the ring rib reinforcement of the gusset plate form a double guarantee, which not only enhances the stability of the corner column itself, but also strengthens the connection reliability between the corner column 1 and the upper gusset plate 2, the lower gusset plate 3, the diagonal brace 4, and the horizontal brace 5, ultimately improving the system stability of the entire lattice tower and reducing the risk of tower collapse under extreme loads (such as strong winds and earthquakes).

[0035] In a preferred embodiment of the present invention, the upper and lower ends of the outer steel pipe 11 are provided with through holes for the upper node plate 2 and the lower node plate 3 to pass through. The inner end of the upper node plate 2 or the lower node plate 3 passes through the through holes and is fixedly connected to the outer wall of the inner steel pipe 12.

[0036] The inner ends of the upper node plate 2 and the lower node plate 3 pass through the through hole of the outer steel pipe 11 and are directly fixed to the outer wall of the inner steel pipe 12. This is equivalent to making the upper node plate 2 and the lower node plate 3 simultaneously form a double anchor with the outer steel pipe 11 (limited by the edge of the through hole) and the inner steel pipe 12 (rigidly fixed). The load can be directly transferred to the inner steel pipe 12 through the upper node plate 2 and the lower node plate 3, skipping the indirect transmission link of the interlayer concrete, which greatly reduces the energy loss and stress concentration risk on the force transmission path. It is especially suitable for tower scenarios that are subjected to high-frequency vibration or sudden impact loads.

[0037] It should be noted that the through holes at the upper and lower ends of the outer steel pipe 11 can be processed simultaneously during the factory prefabrication stage, such as by laser cutting or CNC punching. This ensures precise matching of the thickness and width dimensions of the upper node plate 2 and the lower node plate 3, avoiding secondary drilling on-site. Furthermore, the position of the through holes can be directly used as a positioning reference for the installation of the upper node plate 2 or the lower node plate 3. During on-site assembly, simply passing the inner end of the upper node plate 2 or the lower node plate 3 through the through hole and aligning it with the outer wall of the inner steel pipe 12 quickly completes the spatial positioning of the upper node plate 2 or the lower node plate 3 without additional measurement or adjustment, significantly improving assembly efficiency and installation accuracy.

[0038] For example, the upper node plate 2 or the lower node plate 3 is fixed to the through hole on the outer steel pipe 11 and to the outer wall of the inner steel pipe 12 by welding. As a preferred embodiment of the present invention, see Figure 2As shown, multiple inner stiffening plates 14 are connected between the outer steel pipe 11 and the inner steel pipe 12, and the multiple inner stiffening plates 14 are evenly distributed around the outer periphery of the inner steel pipe 12.

[0039] Although the interlayer concrete between the outer steel pipe 11 and the inner steel pipe 12 can transfer part of the load, when subjected to horizontal shear force (such as wind load or seismic load) or torque (such as tower torsional vibration), the inner and outer steel pipes may experience relative radial displacement due to the difference in stiffness. For example, the outer steel pipe may bulge outward while the inner steel pipe may contract inward, causing the interlayer concrete to be crushed and damaged, thus weakening the overall load-bearing capacity of the corner column. In this preferred embodiment, multiple inner stiffening plates 14 are evenly distributed around the outer periphery of the inner steel pipe 12, and their ends are fixedly connected to the inner wall of the outer steel pipe 11 and the outer wall of the inner steel pipe 12, respectively, for example, by welding. This is equivalent to building radial support ribs between the inner and outer steel pipes. The inner stiffening plates 14 can directly constrain the relative radial displacement of the inner and outer steel pipes, forcing them to deform synchronously under stress. This avoids cracking of the interlayer concrete or local instability of the steel pipes due to uncoordinated deformation, significantly improving the overall torsional stiffness and lateral displacement resistance of the corner column. It is especially suitable for lattice towers that are tall and susceptible to horizontal loads.

[0040] As a preferred embodiment of the present invention, see Figure 1 As shown, flanges 15 are fixedly connected to the upper and lower ends of the corner post 1. Flange stiffening plates 16 are fixed between the flanges 15 and the outer wall of the corner post 1. The flanges 15 are provided with third mounting holes 17 between adjacent flange stiffening plates 16. Fastening bolts are passed through the third mounting holes 17 on the two flanges 15 that abut against each other and connected with nuts to realize the fixed connection of adjacent corner posts 1.

[0041] When the flange 15 is subjected to the vertical load of the adjacent corner post 1, it is prone to bending moment due to load eccentricity or horizontal shear force. Stress concentration will form at the connection between the flange 15 and the outer wall of the corner post 1. If the flange 15 and the corner post 1 are relied upon solely by their own welding strength, long-term stress may cause cracking at the flange root. In this preferred embodiment, the flange stiffening plate 16 is fixed between the flange 15 and the outer wall of the corner post 1, which is equivalent to adding a triangular support rib at the connection between the flange 15 and the corner post 1. The stiffening plate is usually a right triangle or trapezoid, with the right angle sides fixed to the outer wall of the flange 15 and the corner post 1 respectively. It can directly resist the bending moment of the flange 15 and disperse the concentrated stress to a larger area of ​​the outer wall of the corner post 1, rather than just concentrating it at the flange root. This greatly improves the shear and bending resistance of the connection between the flange 15 and the corner post 1, and avoids the early failure caused by stress concentration in traditional flanges 15 without stiffening plates.

[0042] It should be noted that the flanges 15 at the upper and lower ends of the corner post 1 can be prefabricated and welded simultaneously with the corner post 1 (outer steel pipe 11, inner steel pipe 12) in the factory. The flatness of the flanges 15 and the diameter and spacing of the third mounting holes 17 can be controlled with high precision through CNC machining, avoiding precision errors caused by on-site cutting and welding of flanges. During on-site assembly, it is only necessary to align the end faces of the flanges 15 of adjacent corner posts 1. No complex axis calibration is required. The flat surface of the flanges 15 can provide a positioning reference. Then, the corner post 1 can be fixed by passing high-strength friction-type fastening bolts through the third mounting holes 17 and connecting them with nuts.

[0043] As a preferred embodiment of the present invention, see Figure 1 and Figure 2 As shown, the diagonal brace 4 includes a diagonal brace steel pipe 42 and an insert plate 43 connected to the end of the diagonal brace steel pipe 42; It also includes connecting plates 8, one end of the two connecting plates 8 is connected to the upper node plate 2 or the lower node plate 3 through the first mounting hole 41, and the upper node plate 2 or the lower node plate 3 is sandwiched between the two connecting plates 8; the other end of the two connecting plates 8 is provided with a fourth mounting hole 81 that is fixedly connected to the insert plate 43, and the insert plate 43 is located between the two connecting plates 81.

[0044] Traditional diagonal bracing, if directly connected to the node plate by drilling mounting holes at the ends of the steel pipes, requires weakening the cross-section of the steel pipes. Drilling holes reduces the effective load-bearing area of ​​the pipe wall, easily leading to local buckling at the ends of the diagonal bracing due to the weakened cross-section, especially when the diagonal bracing is subjected to compressive or alternating loads. In this preferred embodiment, the diagonal bracing 4 is connected to external components via end insert plates 43. The diagonal bracing steel pipe 42 only needs to be rigidly fixed to the insert plate 43 (such as a steel plate), for example, by welding or fusion connection. Drilling holes in the diagonal bracing steel pipe 42 is unnecessary, preserving the complete annular cross-section of the diagonal bracing steel pipe 42 and ensuring its torsional and compressive stiffness is not compromised. Simultaneously, the insert plate 43 can be made of thicker, higher-strength steel, such as Q355 steel plate. By increasing the contact area between the insert plate 43 and the connecting plate 8, the load transmitted by the diagonal bracing 4 is dispersed, avoiding localized stress concentration, making it particularly suitable for diagonal bracing bearing large loads.

[0045] The diagonal bracing steel pipe 42 is cylindrical. If it is directly connected to the upper node plate 2 or the lower node plate 3, the angle between the steel pipe axis and the node plate plane needs to be precisely controlled, which is difficult to adjust on site. However, the insert plate 43 is a planar component, and its plane can maintain a preset angle with the axis of the diagonal bracing steel pipe 42 (precisely processed during factory prefabrication). During on-site assembly, it is only necessary to align the plane of the insert plate 43 with the plane of the connecting plate 8 to quickly achieve the positioning of the diagonal bracing angle. There is no need to repeatedly adjust the posture of the steel pipe, which greatly reduces the difficulty of precision control during high-altitude assembly.

[0046] In this preferred embodiment, the upper node plate 2 or the lower node plate 3 is sandwiched between two connecting plates 8, and the connecting plate 8 is bolted to the node plate through the first mounting hole 41. This sandwich-type clamping structure can form a two-way planar constraint on the node plate. On the one hand, it avoids the node plate from bending on one side due to the horizontal shear force of the diagonal brace 4; on the other hand, the synchronous force on the two connecting plates 8 can evenly transfer the load of the diagonal brace 4 to both sides of the node plate, reducing local stress concentration in the node plate. This is especially suitable for scenarios where the diagonal brace is subjected to alternating shear force, thus improving the fatigue life of the node.

[0047] The insert plate 43 at the end of the diagonal brace 4 is located between the two connecting plates 8 and fixed through the fourth mounting hole 81. This design also forms a two-way constraint, which can resist the pull-out force generated by the lateral deformation of the tower. When the diagonal brace 4 is under tension, the clamping structure between the insert plate 43 and the connecting plate 8 can prevent the insert plate 43 from coming out of the connecting plate 8. Furthermore, it can disperse the torque transmitted by the diagonal brace 4. When the tower is torsional, the torque generated by the diagonal brace 4 on the connecting plate 8 can be borne simultaneously by the two connecting plates 8, preventing a single connecting plate 8 from breaking due to excessive torque, and further improving the overall deformation resistance of the connection node.

[0048] Similarly, the diagonal bracing steel pipe 42, insert plate 43, and connecting plate 8 of the diagonal bracing 4 can all be prefabricated in the factory. The welding of the insert plate 43 and the diagonal bracing steel pipe 42 can be ensured by automated equipment to guarantee weld quality. The through holes on the connecting plate 8 corresponding to the first mounting holes 41 on the upper node plate 2 or lower node plate 3, and the fourth mounting holes 81 fixed to the insert plate 43, can be precisely positioned by CNC punching, avoiding quality fluctuations caused by on-site welding of the insert plate 43 and drilling. On-site construction only requires two steps of bolt assembly: connecting the connecting plate 8 to the upper node plate 2 or lower node plate 3, and connecting the insert plate 43 to the connecting plate 8. No complicated welding or cutting operations are required, which greatly shortens the high-altitude construction time and reduces construction safety risks.

[0049] As a preferred embodiment of the present invention, see Figure 1 As shown, there are four first mounting holes 41 and four fourth mounting holes 81, and the four first mounting holes 41 or the four fourth mounting holes 81 are arranged in a rectangular shape.

[0050] The first mounting hole 41 (connecting the connecting plate 8 to the upper node plate 2 or the lower node plate 3) and the fourth mounting hole 81 (connecting the connecting plate 8 to the insert plate 43 of the diagonal brace 4) are the core support points for load transfer. If two or three mounting holes are used, the load is easily concentrated in a few holes, causing the bolts or the plates around the holes to deform due to excessive local stress. In this preferred embodiment, the four first mounting holes 41 or the four fourth mounting holes 81 are arranged in a rectangular shape, which can evenly distribute the vertical pressure and horizontal shear force transmitted by the diagonal brace 4 to the four holes. Each hole only needs to bear 25% of the total load, which greatly reduces the peak value of the single point of force. At the same time, the rectangular distribution of holes can form a planar force system, which can resist axial force, shear force and small-range torque at the same time, avoid load concentration in one direction, and significantly improve the fatigue resistance of the connection node, which is especially suitable for wind power towers and communication towers that bear alternating loads for a long time.

[0051] As a preferred embodiment of the present invention, see Figure 1 As shown, the cross brace 5 includes a cross brace steel pipe 52 and a channel steel 53 connected to the end of the cross brace steel pipe 52. The free end of the channel steel 53 is fixedly connected to the second mounting hole 51.

[0052] In this preferred embodiment, the cross brace 5 is connected to the upper node plate 2 or the lower node plate 3 via the end channel steel 53. The cross brace steel pipe 52 only needs to be rigidly fixed to the channel steel 53 (such as U-shaped channel steel or channel steel), without the need to open holes in the steel pipe body. The annular cross section of the steel pipe can be completely preserved, ensuring that its torsional, compressive, and shear stiffness is not damaged. At the same time, the channel steel 53, as a special connecting component, can be made of high-strength steel. Its own channel structure can provide a larger connection contact area, disperse the load transmitted by the cross brace 5, and avoid local overload of the node plate.

[0053] As a preferred embodiment of the present invention, see Figure 1 As shown, the two ends of the first ring rib 6 are welded and fixed to the upper node plate 2, and the inner side of the first ring rib 6 is welded and fixed to the outer side of the corner post 1; the two ends of the second ring rib 7 are welded and fixed to the lower node plate 3, and the inner side of the second ring rib 7 is welded and fixed to the outer side of the corner post 1.

[0054] The core function of the first ring rib 6 and the second ring rib 7 is to connect adjacent node plates and constrain the deformation of the outer side of the corner column 1. If detachable connections such as bolts are used, the ring ribs are prone to loosening due to installation gaps or long-term stress, resulting in the ring ribs being unable to effectively transfer stress and constrain deformation. In this preferred embodiment, the two ends of the ring ribs are welded to the node plates, such as full welds or fillet welds, so that the ring ribs can form a gapless rigid connection with the upper node plate 2 or the lower node plate 3. Furthermore, the diagonal / horizontal bracing loads borne by adjacent node plates can be directly transferred through the ring ribs, avoiding deformation of a single node plate due to load concentration. At the same time, the inner side of the ring ribs is welded to the outer side of the corner column 1, which can directly apply the annular constraint force of the ring ribs to the outer wall of the corner column 1, effectively limiting the lateral expansion or contraction of the corner column 1 in the node area, and significantly improving the local stiffness of the connection between the corner column 1 and the node plate.

[0055] In one embodiment, the present invention provides a wind turbine tower that includes the above-described lattice tower connection structure.

[0056] 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 connection structure for a lattice tower, characterized in that: It includes a corner post (1) and two or more upper node plates (2) and two or more lower node plates (3) respectively connected to the upper and lower ends of the corner post (1); Both the upper node plate (2) and the lower node plate (3) are provided with a first mounting hole (41) for fixing the diagonal brace (4), and at least one of the upper node plate (2) and the lower node plate (3) is provided with a second mounting hole (51) for fixing the cross brace (5). The upper end of the corner post (1) is connected to the upper node plate (2) with a first ring rib (6), and the lower end of the corner post (1) is connected to the lower node plate (3) with a second ring rib (7). The inner sides of the first ring rib (6) and the second ring rib (7) are connected to the outer side of the corner post (1).

2. The connection structure of the lattice tower according to claim 1, characterized in that: The corner column (1) includes an outer steel pipe (11), an inner steel pipe (12), and a sandwich concrete (13) filled between the outer steel pipe (11) and the inner steel pipe (12). Multiple corner columns (1) are fixedly connected in sequence to form a column body. Prestress is applied to the column body through prestressed tendons (9) arranged in the hollow channel of the inner steel pipe (12).

3. The connection structure of the lattice tower according to claim 2, characterized in that: The upper and lower ends of the outer steel pipe (11) are provided with through holes for the upper node plate (2) and the lower node plate (3) to pass through. The inner end of the upper node plate (2) or the lower node plate (3) passes through the through hole and is fixedly connected to the outer wall of the inner steel pipe (12).

4. The connection structure of the lattice tower according to claim 2, characterized in that: Multiple inner stiffening plates (14) are connected between the outer steel pipe (11) and the inner steel pipe (12), and the multiple inner stiffening plates (14) are evenly distributed around the outer periphery of the inner steel pipe (12).

5. The connection structure of the lattice tower according to claim 1, characterized in that: The upper and lower ends of the corner post (1) are fixedly connected with flanges (15). Flange stiffening plates (16) are fixed between the flanges (15) and the outer wall of the corner post (1). The flanges (15) are provided with third mounting holes (17) between adjacent flange stiffening plates (16). Fastening bolts are passed through the third mounting holes (17) on the two flanges (15) that abut against each other in the adjacent corner post (1) and connected with nuts to realize the fixed connection of adjacent corner posts (1).

6. The connection structure of the lattice tower according to claim 1, characterized in that: The diagonal brace (4) includes a diagonal brace steel pipe (42) and an insert plate (43) connected to the end of the diagonal brace steel pipe (42). It also includes connecting plates (8), one end of the two connecting plates (8) is connected to the upper node plate (2) or the lower node plate (3) through the first mounting hole (41), the upper node plate (2) or the lower node plate (3) is sandwiched between the two connecting plates (8); the other end of the two connecting plates (8) is provided with a fourth mounting hole (81) that is fixedly connected to the insert plate (43), the insert plate (43) is located between the two connecting plates (8).

7. The connection structure of the lattice tower according to claim 6, characterized in that: The number of the first mounting hole (41) and the fourth mounting hole (81) are both four, and the four first mounting holes (41) or the four fourth mounting holes (81) are arranged in a rectangular shape.

8. The connection structure of the lattice tower according to claim 1, characterized in that: The cross brace (5) includes a cross brace steel pipe (52) and a channel steel (53) connected to the end of the cross brace steel pipe (52). The free end of the channel steel (53) is fixedly connected to the second mounting hole (51).

9. The connection structure of the lattice tower according to claim 1, characterized in that: The first ring rib (6) is welded and fixed at both ends to the upper node plate (2), and the inner side of the first ring rib (6) is welded and fixed to the outer side of the corner column (1); The two ends of the second ring rib (7) are welded and fixed to the lower node plate (3), and the inner side of the second ring rib (7) is welded and fixed to the outer side of the corner column (1).

10. A wind turbine tower, characterized in that: Including the connection structure of the lattice tower as described in any one of claims 1 to 9.

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