Wind power tower cylinder external prestressed beam waterproof and anticorrosion system and construction method

Abstract

This invention discloses a waterproof and corrosion-resistant system and construction method for external prestressed tendons of wind turbine towers, relating to the field of wind power tower prestressed structure protection technology. The system includes a pipe inlet waterproofing device installed at the inlet of the pre-embedded pipe in the tower foundation and a tensioning end corrosion protection device installed at the working anchor plate. The pipe inlet waterproofing device includes a sealing section, a first tendon-passing section, and an outwardly expanding guide section arranged sequentially. An elastic sealing element is installed at the tendon-passing position of the steel strand, and a cured seal is formed inside the sealing section. The tensioning end corrosion protection device includes a protective cover and a separator. A corrosion-resistant medium cavity is formed between the separator and the working anchor plate, and an injection area is formed on the other side. The exposed section of the steel strand is located inside the corrosion-resistant medium cavity and is covered by the corrosion-resistant medium. A cured seal is formed around the steel strand in the injection area. This invention reduces the risk of moisture entering the pre-embedded pipe and corroding the exposed section of the steel strand through sealing and outward diversion at the pipe inlet and the corrosion-resistant medium covering and sealing isolation at the tensioning end.

Description

Technical Field

[0001] This invention relates to the field of wind power tower prestressed structure protection technology, and in particular to a waterproof and anti-corrosion system and construction method for external prestressed tendons of wind power towers. Background Technology

[0002] As wind turbine generators develop towards larger sizes and taller towers, concrete towers and hybrid towers are being used more and more widely. To improve the integrity and load-bearing capacity of the tower structure, some wind power concrete towers adopt an external prestressing system. Multiple steel strands emerge from embedded pipes set in the tower foundation and extend along the tower structure to the corresponding tensioning position, where they are tensioned and anchored by anchoring components such as working anchor plates and wedges.

[0003] Wind turbine towers are exposed to the outdoors for extended periods, making the surface of the steel strands susceptible to moisture buildup due to temperature changes, humidity, and condensation. Particularly when ambient temperature fluctuates, condensation can form on the steel strand surface, flowing downwards under gravity. When the steel strands are inserted into the tower foundation through the pre-embedded pipe, this moisture can easily seep into the pipe through the area between the strands and the pipe, causing water accumulation or prolonged dampness inside the pipe. This increases the risk of corrosion to the steel strands and related metal components.

[0004] For waterproofing at the inlet of embedded pipes, existing technologies typically use sealing rings, sealing sleeves, or other sealing components to seal the location where the steel strands pass through, thus limiting moisture from entering the embedded pipe along the steel strands. This type of solution relies primarily on the contact seal between the sealing component and the steel strands to achieve water blocking. However, the sealing performance of the sealing component may decrease when it is affected by long-term vibration of the steel strands, temperature fluctuations, or material aging. Furthermore, simply relying on sealing at the inlet mainly blocks moisture that has already reached the sealing location, lacking effective active diversion measures for moisture flowing along the steel strands towards the embedded pipe.

[0005] On the other hand, at the tensioning end of the external prestressing tendon, in order to ensure that the wrench reliably holds the steel strand, the portion of the steel strand near the working anchor plate usually needs to have its outer protective sheath removed, leaving the steel strand body exposed. If this exposed portion is in contact with air and moisture for a long time, it is prone to corrosion and may affect the durability of the external prestressing tendon.

[0006] To mitigate corrosion of the tensioning end steel strands, existing technologies include using sealing wax, sealant, anti-corrosion grease, or protective covers to protect the anchorage area. However, curing-type protective materials may crack under long-term vibration or relative deformation of the components. When using anti-corrosion grease, it's necessary to consider whether the anti-corrosion medium can adequately cover the exposed steel strands and whether the filled anti-corrosion medium can effectively isolate it from external air and moisture.

[0007] For external prestressed strands composed of multiple steel strands, each strand needs to pass through a protective structure, creating multiple potential pathways for media leakage and environmental media intrusion at the corresponding strand-passing locations. If only a regular protective cover is installed outside the tensioning end and filled with anti-corrosion media, problems such as insufficient sealing at the strand-passing locations and communication between the anti-corrosion media and the external environment may still exist, thus affecting the long-term protective effect of the anti-corrosion media.

[0008] Furthermore, the water ingress problem at the pre-embedded pipe inlet and the corrosion problem at the exposed steel strands at the tensioning end occur at different locations within the same external prestressed tendon. Existing protective measures often involve local sealing or anti-corrosion treatment for specific locations. It is necessary to implement targeted protection measures for the water ingress path at the pre-embedded pipe inlet and the corrosion path of the exposed steel strands at the tensioning end, taking into account the actual characteristics of the external prestressed tendon, in order to improve the waterproof and corrosion resistance reliability of the external prestressed tendon during long-term service. Summary of the Invention

[0009] The purpose of this invention is to provide a waterproof and corrosion-resistant system and construction method for external prestressed tendons of wind turbine towers, which reduces the amount of water flowing along the steel strands towards the embedded pipe and entering the interior of the embedded pipe, as well as reduces the contact between external air and moisture and the exposed sections of the steel strands, thereby improving the waterproof and corrosion-resistant performance of the external prestressed tendons under long-term outdoor service conditions.

[0010] To achieve the above objectives, the present invention provides a waterproof and anti-corrosion system for external prestressed tendons of wind turbine towers. The external prestressed tendons include multiple steel strands, which are passed through pre-embedded pipes in the tower foundation and anchored by working anchor plates. The waterproof and anti-corrosion system includes a pipe opening waterproof device and a tensioning end anti-corrosion device. The waterproofing device at the pipe opening includes a sealing part, a first threading part, and a flow guiding part arranged sequentially along the direction of the steel strand toward the pre-embedded pipe. The first threading part is provided with a first threading hole for each of the steel strands to pass through. Each first threading hole is provided with a first elastic sealing element that seals with the corresponding steel strand. The sealing part is provided with a first cured sealing body formed around the steel strand. The flow guiding part extends outward and its outer edge extends beyond the outer edge of the pipe opening of the pre-embedded pipe. The anti-corrosion device at the tensioning end includes a protective cover that is sealed to the working anchor plate and a partition disposed inside the protective cover. The partition is provided with a second through hole for each of the steel strands to pass through, and each of the second through holes is provided with a second elastic sealing element that seals with the corresponding steel strand. A corrosion-resistant medium cavity is formed between the separator and the working anchor plate. A glue injection area is formed on the side of the separator away from the working anchor plate. The exposed section of the steel strand located outside the working anchor plate is located in the corrosion-resistant medium cavity. The corrosion-resistant medium cavity is filled with a corrosion-resistant medium covering the exposed section. A second curing sealant is provided in the glue injection area surrounding the steel strand.

[0011] In some technical solutions, the sealing part has an injection opening that is open away from the pre-embedded pipe, and the sealing part, the first threading part, and the guide part are connected to form an integral cover; The sealing part is cup-shaped, and the guide part is an annular skirt structure that gradually expands outward from the first threaded part.

[0012] In some technical solutions, the first elastic seal includes a first elastic sleeve extending axially along the corresponding steel strand, one end of the first elastic sleeve being sealed to the wall of the corresponding first through hole, and the other end being sleeved and pressed against the outer periphery of the corresponding steel strand.

[0013] In some technical solutions, the first elastic sleeve presses against the corresponding steel strand by its own elastic restoring force, and / or the outer periphery of the first elastic sleeve is provided with a tightening member for tightening the first elastic sleeve toward the corresponding steel strand.

[0014] In some technical solutions, the plurality of second through holes are arranged in accordance with the positions of the prestressed holes on the working anchor plate; The exposed section of the steel strand located outside the working anchor plate, with the protective sheath removed, is entirely within the anti-corrosion medium cavity. The portion of the steel strand retaining the protective sheath extends into the anti-corrosion medium cavity and passes through the separator via the corresponding second through hole.

[0015] In some technical solutions, the second elastic seal includes a second elastic sleeve extending axially along the corresponding steel strand, one end of the second elastic sleeve being sealed to the wall of the corresponding second through hole, and the other end being sleeved and pressed against the outer periphery of the corresponding steel strand. The protective cover has an injection opening at the end of the injection area opposite to the separator, and the second cured sealant is formed by curing a curable sealant injected through the injection opening.

[0016] In some technical solutions, the anti-corrosion medium cavity is connected to both the medium injection pipe and the exhaust pipe; The communication position between the medium injection pipe and the anti-corrosion medium cavity is adjacent to the working anchor plate, and the communication position between the exhaust pipe and the anti-corrosion medium cavity is adjacent to the partition, so that the anti-corrosion medium input by the medium injection pipe fills the anti-corrosion medium cavity from the working anchor plate side to the partition side.

[0017] In some technical solutions, mounting grooves are provided on both sides of the working anchor plate, and the medium injection pipe and the exhaust pipe are respectively inserted into the corresponding mounting grooves and sealed to the working anchor plate.

[0018] In some technical solutions, the protective cover includes a cover sidewall that surrounds the anti-corrosion medium cavity and an upturned part that surrounds the glue injection area, wherein the cover sidewall, the partition and the upturned part are integrally formed; The protective cover and the working anchor plate are bonded and sealed with sealant, and the surface of the protective cover for bonding with the working anchor plate is provided with a roughened structure.

[0019] This invention also provides a waterproof and corrosion-resistant construction method for external prestressed tendons of wind turbine towers, comprising: A waterproof device is installed at the pipe opening of the pre-embedded pipe in the tower foundation, allowing multiple steel strands to pass through the waterproof device. The threading position of each steel strand is sealed by an elastic sealant, and a curable sealing material is injected into the side of the elastic sealant away from the pre-embedded pipe to form a seal. At the same time, the guide part of the waterproof device extends beyond the outer edge of the pipe opening of the pre-embedded pipe. At the tensioning end of the steel strand, the protective cover is sealed to the working anchor plate. A partition is set inside the protective cover to form an anti-corrosion medium cavity on one side of the working anchor plate and an injection area on the other side of the partition, and the exposed section of the steel strand is located in the anti-corrosion medium cavity. The anti-corrosion medium is injected into the anti-corrosion medium cavity from a position adjacent to the working anchor plate, and the gas in the anti-corrosion medium cavity is discharged from a position adjacent to the partition, so that the anti-corrosion medium fills the anti-corrosion medium cavity and covers the exposed section. After the anti-corrosion medium is filled, a curable sealant is injected into the injection area, and the curable sealant is cured around the steel strand to form a seal.

[0020] Compared with the above-mentioned background technology, the wind turbine tower external prestressed tendon waterproofing and corrosion protection system provided by the present invention has at least the following beneficial effects: By installing a waterproof device at the pre-embedded pipe inlet with functions of thread-through sealing and outward flow guidance, water flowing along the steel strand towards the pre-embedded pipe is sealed and blocked at the thread-through point, and can be guided to the outside of the pre-embedded pipe inlet through the guide section, thereby reducing the possibility of water entering the pre-embedded pipe and forming water accumulation. By setting a corrosion-resistant medium cavity and a glue injection area formed by a protective cover and separator at the tensioning end, the exposed section of the steel strand is placed in a corrosion-resistant medium-enclosed environment. At the same time, the elastic seal at the thread-through point and the curing seal formed by the glue injection area achieve multi-level isolation, thereby reducing the entry of external air and moisture into the corrosion-resistant medium cavity, improving the long-term corrosion resistance reliability of the exposed section of the steel strand, which is beneficial to improving the durability of external prestressed tendons under long-term outdoor service conditions, and reducing the difficulty of later maintenance. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention 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 embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the overall structure of the wind turbine tower external prestressed tendon waterproofing and corrosion protection system provided in an embodiment of the present invention; Figure 2 This is a cross-sectional view of the anti-corrosion device at the tensioning end provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the pipe waterproofing device provided in an embodiment of the present invention; Figure 4 for Figure 3 A schematic diagram of the waterproofing device at the pipe opening from another perspective.

[0023] Figures 1 to 4 Chinese figure labels: 1. Tower foundation; 2. Embedded pipe; 3. Steel strand; 4. Waterproofing device at pipe opening; 41. Sealing section; 42. First strand insertion section; 43. First strand insertion hole; 44. Flow guiding section; 5. Anti-corrosion device at tensioning end; 51. Protective cover; 52. Separator; 53. Second strand insertion hole; 54. Anti-corrosion medium cavity; 55. Glue injection area; 56. Medium injection pipe; 57. Exhaust pipe; 6. Working anchor plate. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0026] Please refer to this as well. Figures 1 to 4 This invention provides a waterproof and corrosion-resistant system for external prestressed tendons in wind turbine towers, which is applied to the external prestressed structure of wind turbine concrete towers. The external prestressed tendons include multiple steel strands 3, which pass through embedded pipes 2 set in the tower foundation 1 and extend to the tensioning end for anchoring via working anchor plates 6.

[0027] The waterproof and corrosion-resistant system of this embodiment includes a pipe opening waterproofing device 4 installed at the pipe opening of the pre-embedded pipe 2 and a tensioning end corrosion-resistant device 5 installed at the working anchor plate 6. The pipe opening waterproofing device 4 is used to block, guide, and seal water at the point where the steel strand 3 enters the pre-embedded pipe 2, so as to reduce the entry of condensate or other liquids flowing downward along the surface of the steel strand 3 into the interior of the pre-embedded pipe 2. The tensioning end corrosion-resistant device 5 is used to provide airtight corrosion protection for the exposed part of the steel strand 3 on the outside of the working anchor plate 6.

[0028] The pipe-end waterproofing device 4 includes a sealing section 41, a first threading section 42, and a flow guiding section 44 arranged sequentially along the direction of the steel strands 3 toward the embedded pipe 2. The first threading section 42 has multiple first threading holes 43 corresponding to the multiple steel strands 3, and each steel strand 3 passes through its corresponding first threading hole 43. A first elastic sealing element is provided at each first threading hole 43, forming a sealing fit with the outer periphery of the corresponding steel strand 3 to reduce water seepage into the embedded pipe 2 through the gap between the first threading hole 43 and the steel strand 3.

[0029] The sealing section 41 is located on the side of the first threaded section 42 opposite to the pre-embedded pipe 2. The sealing section 41 contains a first curing sealant formed around multiple steel strands 3. The first curing sealant is filled and cured by a curable sealing material. Based on the partial sealing of the steel strands 3 by the first elastic sealant, it further seals the possible moisture passage between the steel strands 3 and the pipe opening waterproof device 4, thereby forming a composite sealing method that combines elastic sealing and curing sealing.

[0030] The guide section 44 is located on the side of the first through section 42 facing the embedded pipe 2, and extends radially outward from the first through section 42. In the installed state, the outer edge of the guide section 44 is located outside the outer edge of the pipe opening of the embedded pipe 2. When condensate flows along the steel strand 3 towards the embedded pipe 2, some of the water is blocked by the first elastic seal and the first solidified seal. The water flowing to the outer surface of the pipe opening waterproof device 4 is discharged radially outward along the guide section 44 and drips from the periphery of the pipe opening of the embedded pipe 2, thereby reducing the possibility of liquid entering the interior of the embedded pipe 2.

[0031] The anti-corrosion device 5 at the tensioning end includes a protective cover 51 and a partition 52 disposed inside the protective cover 51. The end of the protective cover 51 facing the working anchor plate 6 is sealed to the working anchor plate 6. The partition 52 is spaced apart from the working anchor plate 6, thereby forming an anti-corrosion medium cavity 54 between the partition 52 and the working anchor plate 6. An adhesive injection area 55 is formed on the side of the partition 52 away from the working anchor plate 6.

[0032] The separator 52 is provided with multiple second threading holes 53 corresponding to multiple steel strands 3, and each steel strand 3 passes through the corresponding second threading hole 53. A second elastic sealing element is provided at each second threading hole 53, and the second elastic sealing element is in sealing cooperation with the outer periphery of the corresponding steel strand 3 to seal the threading position at the separator 52.

[0033] During the tensioning process, at least a portion of the protective sheath of the steel strand 3 located outside the working anchor plate 6 is removed, thus forming an exposed section of the steel strand 3. In this embodiment, the exposed section of the steel strand 3 is located within the anti-corrosion medium cavity 54, which is filled with anti-corrosion medium, so that the anti-corrosion medium covers the exposed section of the steel strand 3, thereby reducing the direct contact between the exposed steel strand and the outside air and moisture.

[0034] The adhesive injection area 55 is located on the side of the separator 52 opposite to the working anchor plate 6. A second curing seal is provided in the adhesive injection area 55, which surrounds multiple steel strands 3. The second curing seal cooperates with the second elastic seal provided at the second through hole 53 to further isolate the anti-corrosion medium cavity 54 from the external environment, thereby reducing the possibility of external air and moisture entering the anti-corrosion medium cavity 54 and helping the anti-corrosion medium to maintain a protective state for a long time.

[0035] In some embodiments, the sealing section 41 has an injection opening that is open away from the pre-embedded pipe 2. After the pipe waterproofing device 4 is installed and multiple steel strands 3 pass through the first through hole 43, a curable sealant can be injected into the sealing section 41 through the injection opening. The curable sealant flows into the sealing section 41 and is distributed around the multiple steel strands 3, forming a first cured seal after curing.

[0036] The sealing part 41, the first threading part 42, and the guide part 44 are connected to form an integrated cover. The integrated structure helps to reduce the assembly seams between the sealing part 41, the first threading part 42, and the guide part 44, reducing the possibility of moisture entering the pre-embedded pipe 2 through the assembly connection parts, and also facilitates overall installation on site.

[0037] The sealing section 41 is cup-shaped, with an interior space for containing curable sealant. The opening of the cup-shaped structure faces away from the pre-embedded pipe 2, allowing the curable sealant to be easily injected from above or the outside and held within the sealing section 41 by gravity until it cures.

[0038] The guide section 44 is an annular skirt structure that gradually expands radially outward from the first threaded section 42. The guide section 44 is arranged circumferentially around multiple steel strands 3, and its outer edge extends outward relative to the opening of the pre-embedded pipe 2. When water flows downward along the outer surface of the steel strands 3 or the waterproof device 4 at the pipe opening, the guide section 44 can change the water flow path, causing the water to be discharged away from the opening of the pre-embedded pipe 2.

[0039] In a preferred embodiment, the flow guide 44 extends downward and radially outward from the first through-beam 42, forming an umbrella-like flow guide structure. The angle between the flow guide 44 and the horizontal plane can be set to approximately 30° to balance the drainage capacity of the liquid along the surface of the flow guide 44 with the overall structural dimensions of the pipe opening waterproof device 4. The outer edge of the flow guide 44 extends radially outward relative to the outer edge of the pipe opening of the pre-embedded pipe 2 by a distance preferably not less than 50 mm, so that the liquid flowing along the flow guide 44 can fall to the periphery of the pipe opening of the pre-embedded pipe 2 after leaving its outer edge, further reducing the possibility of liquid backflow or dripping into the interior of the pre-embedded pipe 2.

[0040] The waterproofing device 4 at the pipe opening can be integrally molded from engineering plastic. In a preferred embodiment, the waterproofing device 4 uses ASA engineering plastic, namely acrylonitrile-styrene-acrylate copolymer, and is formed by injection molding into an integral structure of the sealing part 41, the first threading part 42, and the guiding part 44. ASA engineering plastic has good outdoor weather resistance, UV aging resistance, salt spray resistance, and alkaline environment resistance, making it suitable for the long-term outdoor service environment of wind turbine towers. At the same time, using an electrically insulating engineering plastic as the main material of the waterproofing device 4 helps to reduce the risk of galvanic corrosion when it comes into direct contact with the steel strand 3. The wall thickness of the main body of the waterproofing device 4 can be set to 2.5-4mm to balance structural strength, molding performance, and dimensional stability under long-term temperature change conditions.

[0041] In other alternative embodiments, the main material of the pipe waterproofing device 4 can also be glass fiber reinforced ASA material, PC / ASA alloy, SMC molded fiberglass, or galvanized steel. The above materials can be selected according to the wind farm environmental conditions, structural strength requirements, weather resistance requirements, and manufacturing conditions, and are not limited to ASA engineering plastics.

[0042] In some embodiments, the first elastic seal includes a first elastic sleeve extending axially along the corresponding steel strand 3. The first elastic sleeve is disposed at the first through hole 43, one end of which is sealed to the hole wall of the corresponding first through hole 43, and the other end extends axially along the steel strand 3 and is sleeved on the outer periphery of the corresponding steel strand 3.

[0043] The first elastic sleeve is made of a material with elastic deformation capability. After the steel strand 3 is inserted into the first elastic sleeve, the first elastic sleeve adheres to and presses against the outer surface of the steel strand 3 under its own elasticity, thereby reducing the annular gap between the first elastic sleeve and the steel strand 3.

[0044] The first elastic sleeve has a certain extension length along the axial direction of the steel strand 3. Compared with the sealing form that only forms line contact or narrow band contact at the end face of the first through hole 43, it can form a contact sealing area that extends along the axial direction of the steel strand 3, thereby improving the barrier ability of the through hole position to moisture.

[0045] The first elastic sleeve and the wall of the first through hole 43 are sealed together, making it difficult for moisture to pass between the outer periphery of the first elastic sleeve and the wall of the first through hole 43. Thus, the first elastic sleeve forms a seal on the outer periphery of the steel strand 3, and a seal is formed between the first elastic sleeve and the first through hole 43, thereby blocking the moisture passage at the first through hole 43.

[0046] In some embodiments, as one implementation, the first elastic sleeve presses against the corresponding steel strand 3 by its own elastic restoring force. The effective inner diameter of the first elastic sleeve before the steel strand 3 is inserted is smaller than the outer diameter of the corresponding insertion part of the steel strand 3. After the steel strand 3 is inserted, the first elastic sleeve undergoes radial elastic expansion, thereby generating an elastic restoring force towards the steel strand 3 and continuously adhering to the outer surface of the steel strand 3.

[0047] In another embodiment, a tightening member is provided on the outer periphery of the first elastic sleeve. The tightening member can apply a radial tightening force to the first elastic sleeve, so that the first elastic sleeve further compresses the steel strand 3. The tightening member can be provided at a position near the free end of the first elastic sleeve, or one or more members can be provided according to the required sealing length.

[0048] The tightening element can be, for example, an elastic hoop, a hose clamp, or other annular tightening structure capable of applying radial tightening force to the first elastic sleeve. When an additional tightening element is used, the tightening degree can be adjusted to adapt the first elastic sleeve to steel strands 3 with different outer diameters, and to compensate for possible elastic changes that may occur in the elastic sleeve after long-term use.

[0049] The first elastic sleeve's own elastic tightening and the external tightening component can be used alone or in combination. When used in combination, the elasticity of the first elastic sleeve itself is used to form an initial seal, and the tightening component further increases the degree of compression of the first elastic sleeve on the outer periphery of the steel strand 3 to adapt to long-term vibration, temperature changes and other working conditions of the steel strand 3.

[0050] In some embodiments, the plurality of second through holes 53 on the separator 52 are arranged in accordance with the positions of the prestressed holes on the working anchor plate 6, so that each steel strand 3 passing through the working anchor plate 6 can continue to pass through the corresponding second through hole 53 along its original extension direction, reducing the possibility of additional contact or local stress caused by lateral deflection of the steel strand 3.

[0051] A predetermined distance is maintained between the separator 52 and the working anchor plate 6 to form a corrosion-resistant medium cavity 54 with sufficient axial length between them. The exposed section of the steel strand 3 located outside the working anchor plate 6, with the protective sleeve removed, is entirely located within the corrosion-resistant medium cavity 54, so that the corrosion-resistant medium filling the corrosion-resistant medium cavity 54 can cover the exposed areas of the steel strand that require key corrosion protection.

[0052] The portion of the steel strand 3 retaining the protective sheath extends from the anti-corrosion medium cavity 54 to the separator 52, and passes through the separator 52 via the corresponding second through hole 53 and the second elastic seal. Therefore, the transition position of the steel strand 3 from the exposed section to the portion retaining the protective sheath can be located inside or adjacent to the anti-corrosion medium cavity 54, which helps reduce the possibility of direct contact between the exposed steel strand and the external environment.

[0053] Through the above spatial arrangement, the anti-corrosion medium cavity 54 does not only cover the surface of the working anchor plate 6, but forms a certain length of protective range along the axial direction of the steel strand 3, so that the exposed section of the steel strand 3 is entirely in the anti-corrosion medium covering environment.

[0054] In some embodiments, the second elastic seal includes a second elastic sleeve extending axially along the corresponding steel strand 3, one end of the second elastic sleeve being sealed to the hole wall of the corresponding second through hole 53, and the other end extending axially along the steel strand 3 and sleeved on the outer periphery of the steel strand 3.

[0055] After the steel strand 3 passes through the second elastic sleeve, the second elastic sleeve adheres to and presses against the outer surface of the steel strand 3 by its own elastic deformation capacity, so as to reduce the migration of the anti-corrosion medium in the anti-corrosion medium cavity 54 along the second through hole 53 to the glue injection area 55, and at the same time reduce the large amount of curable sealant in the glue injection area 55 flowing into the anti-corrosion medium cavity 54.

[0056] The tightening method of the second elastic sleeve can be the same as that of the first elastic sleeve. That is, the second elastic sleeve can tighten itself to the outer periphery of the steel strand 3 by relying on its own elastic restoring force, or additional tightening structures such as elastic clamps or hose clamps can be added to the outer periphery of the second elastic sleeve to further improve the sealing reliability at the second through hole 53. The above two tightening methods can be used alone or in combination.

[0057] The protective cover 51 forms an injection opening at the end of the injection area 55 opposite to the separator 52. After the anti-corrosion medium cavity 54 is filled with anti-corrosion medium, curable sealant can be injected into the injection area 55 through the injection opening.

[0058] After the curable sealant enters the injection area 55, it is distributed around the multiple steel strands 3 and fills the spaces between the steel strands 3 and between the steel strands 3 and the protective cover 51. After the curable sealant cures, it forms a second cured seal, thereby further forming an integral sealing layer outside the separator 52 and the second elastic seal.

[0059] The second elastic seal is used to locally seal each steel strand 3, while the second solidified seal seals the area where multiple steel strands 3 are located. The two work together to form a composite sealing structure that combines individual sealing with overall sealing.

[0060] In some embodiments, the anti-corrosion medium cavity 54 is connected to the medium injection pipe 56 and the exhaust pipe 57, respectively. The medium injection pipe 56 is used to deliver the anti-corrosion medium into the anti-corrosion medium cavity 54, and the exhaust pipe 57 is used to discharge the air in the anti-corrosion medium cavity 54 during the anti-corrosion medium injection process.

[0061] The communication position between the medium injection pipe 56 and the anti-corrosion medium cavity 54 is located near the working anchor plate 6, and the communication position between the exhaust pipe 57 and the anti-corrosion medium cavity 54 is located near the partition 52. During normal system installation, the communication position of the medium injection pipe 56 within the cavity is at a relatively low position in the anti-corrosion medium cavity 54, and the communication position of the exhaust pipe 57 within the cavity is at a relatively high position.

[0062] During the filling of the anti-corrosion medium, the anti-corrosion medium enters the anti-corrosion medium cavity 54 through the medium injection pipe 56 and gradually expands from the side adjacent to the working anchor plate 6 to the side adjacent to the partition 52. As the anti-corrosion medium liquid level or filling interface gradually rises, the original air is driven upward and discharged through the exhaust pipe 57, thereby reducing the possibility of forming large residual cavities in the anti-corrosion medium cavity 54.

[0063] In a preferred embodiment, the anti-corrosion medium is an oil-based medium with anti-corrosion properties, such as preservative grease. During the medium injection process, the anti-corrosion medium can be continuously introduced into the anti-corrosion medium cavity 54 while keeping the vent pipe 57 in an venting state, so that the anti-corrosion medium is gradually pushed from the lower part to the upper part of the anti-corrosion medium cavity 54. When the anti-corrosion medium appears at the vent pipe 57 or when it is confirmed by other means that the anti-corrosion medium has reached the upper region of the anti-corrosion medium cavity 54, it can be determined that the anti-corrosion medium cavity 54 is basically filled.

[0064] When the anti-corrosion medium is filled to the position of the adjacent partition 52, the exposed section of the steel strand 3 in the anti-corrosion medium cavity 54 is covered by the anti-corrosion medium. Afterwards, the medium injection pipe 56 and the exhaust pipe 57 can be closed or sealed to maintain the protective state of the anti-corrosion medium cavity 54.

[0065] In some embodiments, mounting grooves are provided on both sides of the working anchor plate 6, one mounting groove for arranging the medium injection pipe 56 and the other mounting groove for arranging the exhaust pipe 57. The medium injection pipe 56 and the exhaust pipe 57 are respectively inserted into the corresponding mounting grooves, so that the two channels can communicate with the anti-corrosion medium cavity 54 without significantly occupying the space for multiple steel strands 3 to pass through.

[0066] The medium injection pipe 56 and the exhaust pipe 57 are respectively sealed with the working anchor plate 6 to prevent the anti-corrosion medium from leaking from the outer periphery of the channel to the installation groove, and at the same time to prevent external moisture from entering the interior of the tensioning end anti-corrosion device 5 along the corresponding installation position.

[0067] The medium injection pipe 56 and the exhaust pipe 57 are arranged separately on both sides of the working anchor plate 6, which is conducive to on-site identification and connection of the corresponding injection equipment and exhaust structure, and can reduce mutual interference between the two channels.

[0068] The aforementioned medium injection pipe 56 and exhaust pipe 57 are not limited to being installed within the mounting groove of the working anchor plate 6. In another optional embodiment, openings communicating with the anti-corrosion medium cavity 54 can be respectively provided on the side wall of the protective cover 51, and the medium injection pipe 56 and / or exhaust pipe 57 can be positioned at the corresponding openings. Preferably, the communication position between the medium injection pipe 56 and the anti-corrosion medium cavity 54 is still located on the side adjacent to the working anchor plate 6, and the communication position between the exhaust pipe 57 and the anti-corrosion medium cavity 54 is still preferably located on the side adjacent to the partition 52, to maintain a filling method in which the anti-corrosion medium gradually fills from a low position to a high position and expels air from the cavity. Therefore, as long as the functions of medium injection and cavity venting can be achieved, the specific mounting carrier and orientation of the medium injection pipe 56 and exhaust pipe 57 can be adjusted according to the structure of the protective cover 51 and the working anchor plate 6.

[0069] In some embodiments, the protective cover 51 includes a cover sidewall that surrounds the anti-corrosion medium cavity 54 and an upturned portion that surrounds the glue injection area 55. The cover sidewall, the partition 52, and the upturned portion are integrally formed. The integrally formed structure can reduce the connection seams between the various components inside the protective cover 51 and improve the integrity between the partition 52 and the cover sidewall.

[0070] In a preferred embodiment, the height of the anti-corrosion medium cavity 54 along the extension direction of the steel strand 3 is set to 200-500 mm, so that the exposed section of the steel strand without the protective sheath on the outside of the working anchor plate 6 can be fully accommodated within the anti-corrosion medium cavity 54, and sufficient space is provided for the anti-corrosion medium to cover the exposed section. The separator 52, on the side opposite to the working anchor plate 6, forms the upper structure of the adhesive injection area 55, and its height along the extension direction of the steel strand 3 can be set to 30-100 mm to provide space for the curable sealant.

[0071] The protective cover 51 can be molded from engineering plastics. In a preferred embodiment, the protective cover 51 is made of ASA engineering plastic, and the side walls, partitions 52, and upper structure forming the injection molding area 55 are integrally injection molded. ASA engineering plastics have good outdoor weather resistance and UV aging resistance, making them suitable for long-term outdoor use in wind turbine towers.

[0072] The end of the protective cover 51 facing the working anchor plate 6 is bonded and sealed to the working anchor plate 6 with sealant. Before assembly, the bonding surfaces of the protective cover 51 and the working anchor plate 6 are roughened to improve the adhesion between the sealant and the surface of the protective cover 51.

[0073] When the protective cover 51 is made of ASA engineering plastic, the bonding surface that contacts the working anchor plate 6 can be roughened by grinding, and then bonded and sealed with neutral silicone sealant. By increasing the roughness of the bonding surface, the bonding stability between the sealant and the bonding surface of the protective cover 51 can be improved.

[0074] During assembly, sealant is applied to the interface between the protective cover 51 and the working anchor plate 6. The protective cover 51 is then installed in the predetermined position, forming a continuous sealed connection between the protective cover 51 and the working anchor plate 6. After the sealant has cured, the protective cover 51, the working anchor plate 6, and the separator 52 together define the anti-corrosion medium cavity 54.

[0075] The sealing connection between the protective cover 51 and the working anchor plate 6 serves two purposes: firstly, to prevent the anti-corrosion medium from leaking from the end of the anti-corrosion medium cavity 54 near the working anchor plate 6; and secondly, to reduce the possibility of external moisture and air entering the anti-corrosion medium cavity 54 from the connection interface between the protective cover 51 and the working anchor plate 6.

[0076] In addition to the waterproof and anti-corrosion system for external prestressed tendons of wind turbine towers disclosed in the above embodiments, this embodiment provides a waterproof and anti-corrosion construction method for external prestressed tendons of wind turbine towers, which can be used to form the waterproof and anti-corrosion system in the above embodiments.

[0077] First, install the pipe opening waterproofing device 4. Before the steel strand 3 enters the pre-embedded pipe 2 in the tower foundation 1 or during the installation of the steel strand 3, install the pipe opening waterproofing device 4 at the pipe opening of the pre-embedded pipe 2, so that multiple steel strands 3 pass through the corresponding first threading holes 43 on the first threading part 42.

[0078] The first elastic seal at each of the first through holes 43 is respectively fitted and pressed onto the outer periphery of the corresponding steel strand 3, thereby sealing the through gap between the steel strand 3 and the first through hole 43. After the installation of the first elastic seal is completed, a curable sealant is injected into the sealing part 41 located on the side of the first through part 42 away from the pre-embedded pipe 2, so that the curable sealant is distributed around the multiple steel strands 3 and cured to form a first cured seal.

[0079] Adjust or maintain the position of the pipe opening waterproofing device 4 so that the guide part 44 is located on the side of the first threading part 42 facing the pre-embedded pipe 2, and the outer edge of the guide part 44 extends beyond the outer edge of the pipe opening of the pre-embedded pipe 2. After installation, the water flowing downward along the steel strand 3 is blocked by the first elastic seal and the first cured seal, and the water flowing to the outer surface of the pipe opening waterproofing device 4 is guided to the periphery of the pipe opening of the pre-embedded pipe 2 through the guide part 44.

[0080] Then, the anti-corrosion device 5 at the tensioning end is installed. After the steel strand 3 is tensioned and anchored through the working anchor plate 6, the protective cover 51 is placed at the working anchor plate 6, and the end of the protective cover 51 facing the working anchor plate 6 is sealed to the working anchor plate 6.

[0081] During installation, multiple steel strands 3 are passed through corresponding second through holes 53 on the separator 52, and the second elastic seals at the second through holes 53 are respectively sealed to the outer periphery of the corresponding steel strands 3. The separator 52 forms an anti-corrosion medium cavity 54 on one side of the working anchor plate 6 and an adhesive injection area 55 on the other side of the separator 52 within the protective cover 51, and the exposed section of the steel strands on the outside of the working anchor plate 6 is located within the anti-corrosion medium cavity 54.

[0082] After the protective cover 51 is installed, the anti-corrosion medium is injected into the anti-corrosion medium cavity 54 through the medium injection pipe 56. The anti-corrosion medium enters the anti-corrosion medium cavity 54 from the position adjacent to the working anchor plate 6 and gradually fills towards the direction of the partition 52. While injecting the anti-corrosion medium, the exhaust pipe 57 is kept unobstructed so that the original air in the anti-corrosion medium cavity 54 can be discharged from the position adjacent to the partition 52 through the exhaust pipe 57.

[0083] Continue injecting the anti-corrosion medium, gradually filling the anti-corrosion medium cavity 54 and covering the exposed section of the steel strand 3. By injecting from one side and venting from the opposite side as described above, air is gradually discharged as the anti-corrosion medium is filled, thereby reducing residual gas in the anti-corrosion medium cavity 54.

[0084] After confirming that the anti-corrosion medium has been filled, the medium injection pipe 56 and the exhaust pipe 57 are sealed accordingly. Then, a curable sealant is injected into the glue injection area 55, so that the curable sealant is distributed around the multiple steel strands 3 and fills the space between the steel strands 3 and between the steel strands 3 and the protective cover 51.

[0085] After the curable sealant has cured, a second cured seal is formed in the injection area 55. The second cured seal and the second elastic seal at the separator 52 together form a seal on the outside of the anti-corrosion medium cavity 54, thereby isolating the anti-corrosion medium in the anti-corrosion medium cavity 54 from the external environment.

[0086] Through the above construction method, a waterproof structure combining elastic sealing, curing sealing and radial flow guidance is formed at the pipe opening of the pre-embedded pipe 2, and an anti-corrosion structure combining anti-corrosion medium coating, bundle-by-bundle elastic sealing and external curing sealing is formed at the tensioning end, thereby protecting the different locations of the external prestressed tendons that are susceptible to moisture and corrosion.

[0087] It should be noted that in this specification, relational terms such as first and second are used only to distinguish one entity from several other entities, and do not necessarily require or imply any such actual relationship or order between these entities.

[0088] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. It should be noted that those skilled in the art can make several improvements and modifications to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the protection scope of the present invention.

Claims

1. A waterproof and corrosion-resistant system for external prestressed tendons of a wind turbine tower, wherein the external prestressed tendons comprise multiple steel strands (3), the steel strands (3) passing through pre-embedded pipes (2) in the tower foundation (1) and anchored by working anchor plates (6), characterized in that, Includes a pipe opening waterproofing device (4) and a tensioning end anti-corrosion device (5); The waterproof device (4) includes a sealing part (41), a first threading part (42) and a flow guiding part (44) arranged sequentially along the direction of the steel strand (3) toward the pre-embedded pipe (2). The first threading part (42) is provided with a first threading hole (43) for each of the steel strands (3) to pass through. Each first threading hole (43) is provided with a first elastic sealing element that seals with the corresponding steel strand (3). The sealing part (41) is provided with a first solidified sealing body formed around the steel strand (3). The flow guiding part (44) extends outward and its outer edge extends beyond the outer edge of the pipe opening of the pre-embedded pipe (2). The anti-corrosion device (5) at the tensioning end includes a protective cover (51) that is sealed to the working anchor plate (6) and a partition (52) disposed inside the protective cover (51). The partition (52) is provided with a second through hole (53) for each of the steel strands (3) to pass through. Each of the second through holes (53) is provided with a second elastic sealing element that seals with the corresponding steel strand (3). A corrosion-resistant medium cavity (54) is formed between the separator (52) and the working anchor plate (6). A glue injection area (55) is formed on the side of the separator (52) away from the working anchor plate (6). The exposed section of the steel strand (3) located outside the working anchor plate (6) is located in the corrosion-resistant medium cavity (54). The corrosion-resistant medium cavity (54) is filled with a corrosion-resistant medium covering the exposed section. A second curing seal is provided in the glue injection area (55) surrounding the steel strand (3).

2. The wind turbine tower external prestressed tendon waterproofing and corrosion protection system according to claim 1, characterized in that, The sealing part (41) has an injection opening that is open away from the pre-embedded pipe (2), and the sealing part (41), the first threading part (42) and the guide part (44) are connected to form an integral cover; The sealing part (41) is cup-shaped, and the guide part (44) is an annular skirt structure that gradually expands outward from the first threading part (42).

3. The waterproof and corrosion-resistant system for external prestressed tendons of wind turbine towers according to claim 2, characterized in that, The first elastic seal includes a first elastic sleeve extending axially along the corresponding steel strand (3), one end of the first elastic sleeve being sealed to the hole wall of the corresponding first through hole (43), and the other end being sleeved and pressed against the outer periphery of the corresponding steel strand (3).

4. The wind turbine tower external prestressed tendon waterproofing and corrosion protection system according to claim 3, characterized in that, The first elastic sleeve presses the corresponding steel strand (3) with its own elastic restoring force, and / or the outer periphery of the first elastic sleeve is provided with a tightening member for tightening the first elastic sleeve toward the corresponding steel strand (3).

5. The wind turbine tower external prestressed tendon waterproofing and corrosion protection system according to claim 1, characterized in that, The plurality of second through holes (53) are arranged in accordance with the positions of the prestressed holes on the working anchor plate (6); The exposed section of the steel strand (3) located outside the working anchor plate (6) with the protective sleeve removed is entirely located inside the anti-corrosion medium cavity (54). The portion of the steel strand (3) with the protective sleeve remaining extends into the anti-corrosion medium cavity (54) and passes through the separator (52) through the corresponding second through hole (53).

6. The wind turbine tower external prestressed tendon waterproofing and corrosion protection system according to claim 5, characterized in that, The second elastic seal includes a second elastic sleeve extending axially along the corresponding steel strand (3), one end of the second elastic sleeve being sealed to the hole wall of the corresponding second through hole (53), and the other end being sleeved and pressed against the outer periphery of the corresponding steel strand (3). The protective cover (51) has an injection opening at one end of the injection area (55) away from the separator (52), and the second cured seal is formed by curing a curable sealant injected through the injection opening.

7. The wind turbine tower external prestressed tendon waterproofing and corrosion protection system according to claim 1, characterized in that, The anti-corrosion medium cavity (54) is connected to the medium injection pipe (56) and the exhaust pipe (57) respectively; The communication position between the medium injection pipe (56) and the anti-corrosion medium cavity (54) is adjacent to the working anchor plate (6), and the communication position between the exhaust pipe (57) and the anti-corrosion medium cavity (54) is adjacent to the partition (52), so that the anti-corrosion medium input by the medium injection pipe (56) fills the anti-corrosion medium cavity (54) from the working anchor plate (6) side to the partition (52) side.

8. The waterproof and corrosion-resistant system for external prestressed tendons of wind turbine towers according to claim 7, characterized in that, The working anchor plate (6) is provided with mounting grooves on both sides. The medium injection pipe (56) and the exhaust pipe (57) are respectively inserted into the corresponding mounting grooves and are respectively sealed to the working anchor plate (6).

9. The wind turbine tower external prestressed tendon waterproofing and corrosion protection system according to claim 6, characterized in that, The protective cover (51) includes a cover sidewall that surrounds the anti-corrosion medium cavity (54) and an upturned part that surrounds the glue injection area (55). The cover sidewall, the partition (52) and the upturned part are integrally formed. The protective cover (51) is bonded and sealed to the working anchor plate (6) with sealant, and the surface of the protective cover (51) for bonding with the working anchor plate (6) is provided with a roughened structure.

10. A method for waterproofing and corrosion protection of external prestressed tendons on a wind turbine tower, characterized in that, include: A pipe opening waterproofing device (4) is installed at the pipe opening of the pre-embedded pipe (2) of the tower foundation (1), so that multiple steel strands (3) pass through the pipe opening waterproofing device (4) respectively. The threading position of each steel strand (3) is sealed by an elastic sealant, and a curable sealing material is injected into the side of the elastic sealant away from the pre-embedded pipe (2) to form a seal. At the same time, the guide part (44) of the pipe opening waterproofing device (4) extends to the outer edge of the pipe opening of the pre-embedded pipe (2). At the tensioning end of the steel strand (3), the protective cover (51) is sealed to the working anchor plate (6). A corrosion-resistant medium cavity (54) is formed on one side of the working anchor plate (6) and an adhesive injection area (55) is formed on the other side of the partition (52) by the partition (52) provided in the protective cover (51), and the exposed section of the steel strand (3) is located in the corrosion-resistant medium cavity (54). The anti-corrosion medium is injected into the anti-corrosion medium cavity (54) from a position adjacent to the working anchor plate (6), and the gas in the anti-corrosion medium cavity (54) is discharged from a position adjacent to the partition (52), so that the anti-corrosion medium fills the anti-corrosion medium cavity (54) and covers the exposed section. After the anti-corrosion medium is filled, a curable sealant is injected into the injection area (55) so that the curable sealant cures around the steel strand (3) to form a seal.

Images