A dry-connected UHPC wind turbine tower, a longitudinal joint connection structure, concrete segments, and their preparation method.

Abstract

A dry-connection longitudinal joint connection structure for UHPC wind turbine towers includes a connecting strip A and a connecting strip B. Connecting strip A has a keyway and shear reinforcement A, located on two opposite longitudinal sides of the connecting strip A. An extension section A extends from the upper end of connecting strip A. Connecting strip B has a raised key and shear reinforcement B, located on two opposite longitudinal sides of the connecting strip B. An extension section B extends from the upper end of connecting strip B. Shear reinforcement A and shear reinforcement B are both cast inside the longitudinal side of the concrete segment body. Connecting strip A and connecting strip B are spliced ​​together via the keyway and raised key. After splicing, extension section A and extension section B combine to form a tower segment butt block. The raised key and keyway mechanically engage with the shear reinforcement to form a dual shear resistance system. This invention improves tower assembly efficiency.

Description

Technical Field

[0001] This invention relates to the field of wind turbine tower technology, and in particular to a dry-connected UHPC wind turbine tower, a longitudinal joint connection structure, concrete segments, and their preparation methods. Background Technology

[0002] Against the backdrop of the rapid development of modern wind power technology, wind turbine towers, as key supporting structures for wind turbine generators, are facing unprecedented challenges and opportunities in their design and construction. As the single-unit capacity of wind turbine generators continues to increase, the height and diameter of towers are also constantly growing, placing more stringent demands on the structural performance, construction efficiency, and life-cycle cost control of the towers. To facilitate the transportation of tower sections, segmented towers are gradually becoming the mainstream tower manufacturing solution in the industry. However, there are still many areas for optimization regarding the stability of the longitudinal joints after manufacturing and assembly. Traditional segmented tower segments generally use ordinary precast concrete technology, and their longitudinal joints mostly rely on cast-in-place concrete wet joint technology to achieve structural integrity. However, the insufficient strength of ordinary concrete easily leads to structural damage such as crushing and edge chipping at the ends of the segments, and the wet joint connection process has inherent defects such as long construction cycles, low interface bonding strength, and poor durability. Existing improved technologies employ prefabricated UHPC (ultra-high performance concrete) for the entire tower, which significantly improves overall structural rigidity and reduces cracking risk. However, this leads to a surge in material costs, making it economically unsustainable for large-scale applications. On the other hand, the use of dry bolt connections at longitudinal joints, while shortening construction time, also presents challenges such as corrosion from exposed metal connectors, localized stress concentration during installation leading to weakened cross-sectional strength, and increased overall steel consumption resulting in higher costs. Current technologies have not yet achieved a cost-effective, non-cast-in-place, metal-exposed, segmented tower prefabrication and splicing scheme, thus hindering the development of industrialized wind turbine tower construction. Summary of the Invention

[0003] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a dry-connected UHPC wind turbine tower, a longitudinal joint connection structure, concrete segments and their preparation method, to solve the technical problems such as instability and poor durability at the longitudinal joints after the assembly of segmented wind turbine towers.

[0004] To achieve the above objectives, the present invention provides a dry-connected longitudinal joint connection structure for UHPC wind turbine towers, comprising:

[0005] Connecting strip A is used as a splicing member on one end of the longitudinal side of the main body of concrete pipe segment. The connecting strip A is provided with a keyway and a shear reinforcement A. The keyway and the shear reinforcement A are respectively located on two opposite longitudinal sides of the connecting strip A. An extension section A extends from the upper end of the connecting strip A. The width of the extension section A is smaller than the width of the connecting strip A.

[0006] Connecting strip B serves as the splicing component at the other end of the longitudinal side of the main body of the concrete tunnel segment. Connecting strip B is equipped with a key and shear reinforcement B, located on opposite longitudinal sides of the connecting strip B. An extension section B extends from the upper end of connecting strip B, with the width of the extension section B being less than the width of the connecting strip B. Shear reinforcement A and shear reinforcement B are both cast inside the longitudinal side of the main body of the concrete tunnel segment. Connecting strip A and connecting strip B are spliced ​​together via the keyway and the key. After splicing, the extension section A and extension section B combine to form a tower section butt block, which is used to fit and insert into the butt groove at the bottom of the main body of the concrete tunnel segment. Connecting strip A and connecting strip B have the same height. Connecting strip A and connecting strip B are made of UHPC.

[0007] Optionally, there are multiple keyways and multiple convex keys, and the multiple keyways and multiple convex keys are spliced ​​together in a one-to-one correspondence.

[0008] Optionally, the thickness of both connecting strip A and connecting strip B is 50-100cm; the depth of the keyway is 0.1 to 0.2 times the thickness of connecting strip A, the length is 0.75 to 0.85 times the width of connecting strip A, and the distances from both ends of the keyway along its length to the front and rear walls of connecting strip A are equal; the width of the keyway is 0.3 to 0.5 times its length; and the spacing between the keyways is 1.2 to 1.4 times its width.

[0009] Optionally, the cross-section of the keyway perpendicular to its depth direction is a trapezoidal structure, and the shape of the convex key matches the keyway.

[0010] Optionally, both shear reinforcement A and shear reinforcement B are generally annular structures, with one end of shear reinforcement A being perpendicularly connected to connecting strip A, and one end of shear reinforcement B being perpendicularly connected to connecting strip B.

[0011] Optionally, there are multiple shear reinforcements A and B, with the multiple shear reinforcements A and B being parallel to each other.

[0012] Optionally, the keyway corresponds one-to-one with the shear reinforcement A, and the convex key corresponds one-to-one with the shear reinforcement B.

[0013] The present invention also provides a dry-connected UHPC wind turbine tower concrete segment, including a concrete segment body and a longitudinal joint connection structure as described above. The shear reinforcement A and the shear reinforcement B are both located inside the concrete segment body. The connecting strip A has one side with the shear reinforcement A and the shear reinforcement A is cast and connected to one end of the longitudinal side of the concrete segment body. The connecting strip B has one side with the shear reinforcement B and the shear reinforcement B is cast and connected to the other end of the longitudinal side of the concrete segment body. A butt groove is provided at the middle of the bottom end of the concrete segment body, and the butt groove is used to match and insert with the tower section butt block.

[0014] Optionally, the lower ends of both connecting strip A and connecting strip B are flush with the lower end of the concrete segment body.

[0015] The present invention also provides a dry-connected UHPC wind turbine tower, comprising a plurality of concrete segments as described in claim 7, wherein the plurality of concrete segments are spliced ​​together by the connecting strip A and the connecting strip B to form a tower segment, wherein the plurality of tower segments are staggered and overlapped in sequence, and after overlapping, the tower segment docking block is inserted into the docking groove.

[0016] Optionally, the tower section has four of the concrete segments.

[0017] This invention also provides a method for preparing dry-connected UHPC wind turbine tower concrete segments, comprising the following steps:

[0018] S1, Cast the connecting strip A as described above;

[0019] S2, using the side of the connecting strip A with the keyway as the bottom mold for casting the connecting strip B, and casting the connecting strip B as described above;

[0020] S3, the connecting strip B is used as a longitudinal side mold of the main body mold of the concrete segment, the shear reinforcement B is located inside the main body mold of the concrete segment, the connecting piece A is used as another longitudinal side mold of the main body mold of the concrete segment, the shear reinforcement A is located inside the main body mold of the concrete segment, and concrete is poured into the main body mold of the concrete segment to obtain the concrete segment.

[0021] The beneficial effects of this invention are as follows: When applied to a concrete segment body, the connecting strip A has one side with shear reinforcement A and is cast to one end of the shear reinforcement A on the longitudinal side of the concrete segment body. The connecting strip B has one side with shear reinforcement B and is cast to the other end of the shear reinforcement B on the longitudinal side of the concrete segment body. After connection, a concrete segment is formed. Multiple concrete segments are dry-jointed through the keyway and the convex key to form a tower section. The tower section connecting block is used for joining upper and lower tower sections. This joining structure facilitates rapid, all-weather tower assembly. During on-site assembly, no additional longitudinal joint connecting components are required, further improving tower assembly efficiency. Furthermore, after the tower section connecting block is inserted into the connecting groove at the bottom of the upper concrete segment body, it reinforces the stability of the joint between connecting strip A and connecting strip B, preventing loosening of connecting strip A and connecting strip B, further preventing loosening between multiple concrete segments, and improving the overall performance of the tower. During on-site tower hoisting, the convex key and the keyway have a self-aligning function. In addition, the tower section docking block can also assist workers in positioning the tower connection. The tower sections can be precisely aligned through the docking groove and the tower docking block, which not only improves the efficiency of tower assembly and construction, but also breaks through the limitations of traditional wet joint technology.

[0022] In practical application, after splicing, the convex key and the keyway mechanically engage with the shear reinforcement to form a dual shear-resistant system, significantly increasing the shear bearing capacity of the longitudinal joints between concrete segments and effectively preventing localized cracking at the joints. Furthermore, connecting strips A and B of this invention also function as molds, directly serving as casting molds for both sides of the concrete segment body. This replaces part of the existing casting mold structure, optimizing the design of existing casting molds and reducing mold costs.

[0023] The connecting strips A and B of this invention are made of UHPC (ultra-high performance concrete), which significantly improves the load-bearing capacity of the longitudinal joints of the tower and avoids problems such as cracking and crushing that occur at the longitudinal joints of traditional concrete segments. The main body of the concrete segments uses ordinary concrete instead of entirely UHPC. Furthermore, a row of shear reinforcement along the longitudinal direction effectively combines and synergizes the UHPC formwork and ordinary concrete, reducing the amount of UHPC used. This invention avoids the high cost of using UHPC throughout the tower section and the localized cracking caused by traditional bolted connections. The tower structure is economical and improves the safety and stability of wind turbine towers in harsh natural environments such as high-altitude and offshore areas. In addition, using UHPC as the connecting material for the longitudinal joints of the tower section significantly reduces the overall steel consumption of the tower structure, saving costs.

[0024] Using the side of the connecting strip A with the keyway as the bottom (bottom mold) of the mold for casting the connecting strip B ensures that the formed convex key and the keyway have a high degree of fit and good bonding, preventing the concrete pipe segments from being locally crushed during assembly due to manufacturing errors, thereby improving the stability of the longitudinal joint of the tower connection.

[0025] Connecting strip A and connecting strip B are directly used as casting molds for the left and right ends of the concrete segment body, which replaces part of the existing casting mold structure of the concrete segment body. After concrete is poured into the concrete segment body mold, connecting strip A, connecting strip B, shear reinforcement A and shear reinforcement B are cast as a whole with the concrete segment body, thereby realizing the integrated molding of segmented tower concrete segments, with good bonding, accelerating the splicing of tower sections, and further improving construction efficiency. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of the connecting strip A in an embodiment of the present invention;

[0027] Figure 2 This is a schematic diagram of the structure of the connecting strip B in an embodiment of the present invention;

[0028] Figure 3 This is a schematic diagram of the structure after the connecting strip A and the connecting strip B are spliced ​​together in an embodiment of the present invention;

[0029] Figure 4 This is a structural schematic diagram of the concrete segment described in one of the embodiments of the present invention;

[0030] Figure 5 This is a structural schematic diagram of the concrete segment described in an embodiment of the present invention from another perspective;

[0031] Figure 6 This is a schematic diagram of the structure after the two tower sections are spliced ​​together in an embodiment of the present invention.

[0032] Explanation of reference numerals in the attached figures:

[0033] 101. Connecting strip A; 102. Keyway; 103. Shear reinforcement A; 104. Extension section A;

[0034] 201. Connecting strip B; 202. Convex key; 203. Shear reinforcement B; 204. Extension section B;

[0035] 301. Concrete segment body; 302. Connecting groove. Detailed Implementation

[0036] The following specific examples illustrate the implementation of the present invention. 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.

[0037] It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of the present invention. Therefore, the drawings only show units relevant to the present invention and are not drawn according to the actual number, shape, and size of units in implementation. In actual implementation, the form, quantity, and proportion of each unit can be arbitrarily changed, and the unit layout may be more complex. The structures, proportions, and sizes shown in the accompanying drawings are only for illustrative purposes to aid those skilled in the art and are not intended to limit the implementation conditions of the present invention. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to the size, without affecting the effects and objectives of the present invention, should still fall within the scope of the technical content disclosed in the present invention. Furthermore, the terms such as "upper," "lower," "left," "right," "middle," and "one" used in this specification are only for clarity of description and are not intended to limit the scope of the present invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the present invention.

[0038] Example 1

[0039] like Figure 1-5 As shown, this embodiment provides a dry-connected longitudinal joint connection structure for UHPC wind turbine towers, including:

[0040] A connecting strip A101 is used as a splicing member on one end of the longitudinal side of the concrete segment body 301. The connecting strip A101 is provided with a keyway 102 and a shear reinforcement A103. The keyway 102 and the shear reinforcement A103 are respectively located on two opposite longitudinal sides of the connecting strip A101. The keyway 102 and the shear reinforcement A103 correspond one-to-one and are located on the same horizontal plane, that is, the keyway 102 and the shear reinforcement A103 are aligned one-to-one. An extension section A104 extends from the upper end of the connecting strip A101. The width of the extension section A104 is smaller than the width of the connecting strip A101.

[0041] A connecting strip B201, used as a splicing member at the other end of the longitudinal side of the concrete segment body 301, is provided with a protruding key 202 and a shear reinforcement B203. The protruding key 202 and the shear reinforcement B203 are respectively located on two opposite longitudinal sides of the connecting strip B201. The protruding key 202 and the shear reinforcement B203 correspond one-to-one and are located on the same horizontal plane, that is, the protruding key 202 and the shear reinforcement B203 are aligned one-to-one. An extension section B204 extends from the upper end of the connecting strip B201. The width of the extension section B204 is smaller than the width of the connecting strip B201. Both the shear reinforcement A103 and the shear reinforcement B203 are cast inside the longitudinal side of the concrete segment body 301, such as... Figure 4 and 5 As shown; the connecting strip A101 and connecting strip B201 are spliced ​​together by the keyway 102 and the convex key 202. After splicing, the extension section A104 and the extension section B204 are combined to form a tower section docking block. The tower section docking block is used to match and insert into the docking groove 302 at the bottom of the concrete segment body 301. The connecting strip A101 and the connecting strip B201 have the same height. The lower end of the connecting strip A101 is flush with the lower end of the connecting strip B201. The upper end of the connecting strip A101 is also flush with the upper end of the connecting strip B201. The upper end of the extension section A104 is flush with the upper end of the extension section B204. The dimensions of the extension section A104 are the same as the dimensions of the extension section B204.

[0042] It should be noted that the widths of connecting strips A101 and B201 refer to the distance between their front and rear ends, as does the width of extension segment A104. The distance between the upper and lower ends of extension segment A104 is its height. The height of extension segment A104 can be greater than or less than its width. The dimensions of extension segment B204 are the same as those of extension segment A104. In this embodiment, the widths of connecting strips A101 and B201 are the same. The width of connecting strip A101 is equal to the thickness of the concrete segment body.

[0043] like Figure 4 and 5As shown, this invention is applied to the concrete segment body 301. The connecting strip A101 has one side with the shear reinforcement A103 and the shear reinforcement A103 is cast and connected to one longitudinal side of the concrete segment body 301. The connecting strip B201 has one side with the shear reinforcement B203 and the shear reinforcement B203 is cast and connected to the other longitudinal side of the concrete segment body 301. After the casting and connection are completed, a concrete segment is formed. Multiple concrete segments are spliced ​​together by the keyway 102 and the convex key 202 to form a tower section. The tower section connecting block is used for splicing the upper and lower tower sections. This splicing structure of the present invention can facilitate the rapid assembly of the tower in all weather conditions, further improving the tower assembly efficiency. Furthermore, after the tower section connecting block is inserted into the connecting groove 302 at the bottom of the upper concrete segment body 301, it can strengthen the splicing stability between the connecting strips A101 and B201, preventing them from loosening and further preventing loosening between multiple concrete segments, thus improving the overall performance of the tower. During on-site tower hoisting, the convex key 202 and the keyway 102 have a self-aligning function. In addition, the tower section connecting block can also assist workers in tower connection positioning. Precise alignment between tower sections can be achieved through the connecting groove 302 and the tower connecting block, which not only improves the efficiency of tower assembly construction but also breaks through the limitations of traditional wet joint technology.

[0044] In this embodiment, the cross-section of the keyway 102 perpendicular to its depth direction is a trapezoidal structure. In other words, the keyway 102 is a trapezoidal structure, which can be understood as the opening size of the keyway 102 gradually decreasing towards the bottom of the groove. However, due to the small gradient, it is not obvious in the attached drawings. The shape of the convex key 202 matches the keyway 102. The depth of the keyway 102 is 10-20cm, and the size of the convex key 202 is determined according to the size of the keyway 102, as long as it can fit snugly into the keyway 102.

[0045] like Figure 6 The diagram shows the actual application of the present invention after splicing. The mechanical interlocking of the convex key 202 and the keyway 102, together with the shear reinforcement, forms a dual shear-resistant system, significantly increasing the shear capacity of the longitudinal joint between concrete segments. Specifically, the mechanical interlocking connection of the convex key 202 and the keyway 102 not only restricts the displacement of the joint but also achieves effective decomposition and transmission of shear force through the trapezoidal structure of the keyway 102, resulting in a more uniform stress distribution on the longitudinal splicing surface and improving the shear strength of the joint. Simultaneously, the arrangement of the shear reinforcement not only effectively restricts the opening deformation of the joint but also provides a residual bearing capacity, significantly improving the ductility of the joint, preventing brittle failure, and, in conjunction with the convex key 202 and the keyway 102, forms a dual shear-resistant system, further enhancing the shear capacity of the joint.

[0046] The connecting strips A101 and B201 are made of ultra-high performance concrete (UHPC), which enhances their crack resistance and durability. UHPC high-strength concrete has high compressive strength, good crack resistance, and good corrosion resistance. Using UHPC material at the joint can improve the safety and stability of wind turbine towers in harsh natural environments such as high altitude, cold regions, and offshore areas.

[0047] Furthermore, the connecting strip A101 and the connecting strip B201 of the present invention also function as molds, and can be directly used as casting molds on both sides of the concrete segment body 301. In other words, they replace part of the existing casting mold structure of the concrete segment body 301, optimize the existing casting mold structure design and reduce mold costs.

[0048] Furthermore, the thickness of both connecting strip A101 and connecting strip B201 is 50-100cm, meaning that connecting strip A101 and connecting strip B201 have a certain thickness to facilitate the setting of the keyway 102 / protruding key 202 and the shear reinforcement A103 / shear reinforcement B203 on both sides, and to ensure a stable connection structure between the connecting strip and the shear reinforcement. The thickness of connecting strip A101 refers to the distance between its left and right sides.

[0049] There are multiple keyways 102 and multiple convex keys 202, and the multiple keyways 102 and multiple convex keys 202 are spliced ​​together in a one-to-one correspondence. Preferably, the multiple keyways 102 and multiple convex keys 202 are distributed longitudinally at equal intervals. The splicing of multiple keyways 102 and multiple convex keys 202 makes the splicing stress points uniform and the spliced ​​structure more stable.

[0050] The depth of the keyway 102 is 0.1 to 0.2 times the thickness of the connecting strip A101, and the length is 0.75 to 0.85 times the width of the connecting strip A101. That is, the length of the connecting strip A101 is 0.75 to 0.85 times the thickness of the concrete pipe segment body. The distances from both ends of the keyway 102 along the length direction to the front and rear walls of the connecting strip A101 are equal. The width of the keyway 102 is 0.3 to 0.5 times its length, and the spacing between the keyways 102 is 1.2 to 1.4 times its width.

[0051] Furthermore, both the shear reinforcement A103 and the shear reinforcement B203 are generally annular structures. One end of the shear reinforcement A103 is perpendicularly connected to the connecting strip A101, and one end of the shear reinforcement B203 is perpendicularly connected to the connecting strip B201. Specifically, when casting the connecting strip (the connecting strip A101 and the connecting strip B201), the shear reinforcements (the shear reinforcement A103 and the shear reinforcement B203) are pre-arranged in the casting mold of the connecting strip. Then, UHPC ultra-high strength concrete is poured into the casting mold of the connecting strip. After the casting is completed, the connecting strip is cast and connected to one end of the shear reinforcement, and the other end of the shear reinforcement is located outside the connecting strip.

[0052] There are multiple shear bars A103 and multiple shear bars B203. The multiple shear bars A103 are parallel to each other, and the multiple shear bars B203 are parallel to each other. The multiple shear bars A103 are distributed at equal intervals in the longitudinal direction, and the multiple shear bars B203 are also distributed at equal intervals in the longitudinal direction. The multiple shear bars are connected to the concrete segment body 301, so that the connection between the connecting strip and the concrete segment body 301 is uniformly stressed, increasing the stability of the overall structure.

[0053] The connecting strip A101 is first cast using a mold. The side of the connecting strip A101 with the keyway 102 serves as the bottom mold for casting the connecting strip B201. This ensures a high degree of fit and good bonding between the formed convex key 202 and the keyway 102, improving the flatness of the concrete segments and preventing local crushing of the concrete segments during assembly due to manufacturing errors. This, in turn, enhances the stability of the longitudinal joints of the tower connection. Before casting the connecting strip B201, a release agent is applied to the side of the connecting strip A101 with the keyway 102 to facilitate demolding.

[0054] Compared with existing dry connection technologies, this invention eliminates the need for pre-embedded flanges and bolts during tower section installation, avoids cross-sectional (longitudinal splice) weakening, maintains a good cross-sectional shape, increases the effective bearing area of ​​concrete, and avoids localized cracking caused by stress concentration during bolt tightening. The invention also features a simple overall structure, a clear force transmission path, and low construction difficulty.

[0055] Example 2

[0056] like Figure 1-5As shown, this embodiment provides a dry-connected UHPC wind turbine tower concrete segment, including a concrete segment body 301 and the longitudinal joint connection structure described in Embodiment 1. Shear reinforcement A103 and shear reinforcement B203 are both located inside the concrete segment body 301. Connecting strip A101 has one side with shear reinforcement A103 and the shear reinforcement A103 is cast and connected to one end of the longitudinal side of the concrete segment body 301. Connecting strip B201 has one side with shear reinforcement B203 and the shear reinforcement B203 is cast and connected to the other end of the longitudinal side of the concrete segment body 301. In this embodiment, the left end of the concrete segment body 301 is cast and connected to connecting strip A101, and the right end is connected to connecting strip B201. A butt groove 302 is provided in the middle of the bottom end of the concrete segment body 301, and the butt groove 302 is used for mating and insertion with the tower section butt block.

[0057] Furthermore, the lower ends of both the connecting strip A101 and the connecting strip B201 are flush with the lower end of the concrete segment body 301, and the extension sections A104 and B204 protrude from the upper end of the concrete segment body 301, that is, the parts that are higher than the concrete segment body 301.

[0058] In this invention, during casting, the connecting strips A101 and B201 are directly used as casting molds on both sides of the concrete segment body 301, thus replacing part of the existing casting mold structure for the concrete segment body 301. Specifically, when casting the concrete segment body 301, the shear reinforcement A103 and B203 extend from both sides of the concrete segment body mold into the mold. The connecting strips A101 and B201 close both sides of the concrete segment body mold, and then concrete is poured into the mold. This ensures that the connecting strips A101, B201, A103, and B203 are cast integrally with the concrete segment body 301, thereby achieving integrated molding of segmented tower concrete segments with good bonding. During tower segment assembly, there is no need to install joint connection components again, which is a dry connection method, enabling rapid assembly in all weather conditions and further improving construction efficiency. The connecting strips A101 and B201 replace the structures on both sides of the main body mold of the concrete segment, which optimizes the existing casting mold structure design and reduces mold costs.

[0059] This invention facilitates transportation and assembly / disassembly, and its splicing structure is robust. Compared to existing dry connection technologies, it eliminates the need for pre-embedded flanges and bolts during tower section installation, avoids cross-sectional weakening, maintains a good cross-sectional shape, maximizes the effective bearing area of ​​the concrete, and prevents localized cracking caused by stress concentration during bolt tightening. The overall structure of this invention is simple, the force transmission path is clear, and construction is easy.

[0060] The connecting strips A101 and B201 of this invention are made of UHPC (ultra-high performance concrete), which significantly improves the load-bearing capacity of the longitudinal joints of the tower and avoids problems such as cracking and crushing that occur at the longitudinal joints of traditional concrete segments. The main body 301 of the concrete segment uses ordinary concrete instead of entirely UHPC. Simultaneously, a row of shear reinforcement along the longitudinal direction achieves effective bonding and synergistic effect between the UHPC formwork and ordinary concrete, reducing the amount of UHPC used. This invention avoids the high cost of using UHPC throughout the tower section and the localized cracking caused by traditional bolted connections. The tower structure is economical and improves the safety and stability of wind turbine towers in harsh natural environments such as high-altitude and offshore areas. Furthermore, using UHPC as the connecting material for the longitudinal joints of the tower section significantly reduces the overall steel consumption of the tower structure, saving costs.

[0061] Because existing longitudinal joints of concrete pipe segments may have local unevenness when using grouting or structural adhesive for connection, resulting in reduced fit at the longitudinal joint end faces and affecting the installation and stability of the tower, the keyway 102 on the connector A101 and the convex key 202 on the connector B201 of the present invention have a high degree of matching. During the splicing of concrete pipe segments, grouting or structural adhesive is not required. After splicing, the longitudinal joint is stable, solving the technical problem of reduced fit and unstable joints caused by local unevenness at the longitudinal connection end faces of existing concrete pipe segments.

[0062] Example 3

[0063] like Figure 4-6 As shown, this embodiment provides a dry-connected UHPC wind turbine tower, comprising multiple concrete segments as described in Embodiment 2. These concrete segments are joined together by connecting strips A101 and B201 to form tower sections. The tower sections are sequentially staggered and overlapped. After overlapping, the connecting blocks of the tower sections are inserted into the connecting grooves 302. The sequential staggered overlap of the tower sections means that the longitudinal joint connection structure on each tower section is not vertically aligned with the longitudinal joint connection structure on the adjacent tower section, but is staggered. The longitudinal joint connection structure corresponds to the middle of the lower end of the concrete segment.

[0064] In this embodiment, the tower section comprises four concrete segments, meaning that four concrete segments are spliced ​​together to form one tower section. Multiple tower sections are overlapped and assembled into a tower. After the tower assembly is completed, prestressed tendons are installed for further stabilization. Specifically, the external prestressed tendons can be anchored at one end to the transition section between the tower and its upper steel tower using existing technology, and at the other end to the hollow foundation at the bottom of the tower. Tensioning and locking are accomplished through pre-embedded anchor bolts and load-bearing anchor rings. Alternatively, other existing technologies can be used to install prestressed tendons. By deploying external prestressed tendons on the wind turbine tower and applying longitudinal prestress, the prestressed tendons can effectively counteract the tensile stress on the tower under lateral loads such as wind loads, inhibit concrete cracking and delay crack propagation, while maintaining the natural frequency of the tower to avoid resonance and fatigue failure. This enhances the overall stiffness and stability, significantly improving structural performance and engineering economy.

[0065] In this embodiment, the tower section uses the keyway 102 and the raised key 202 for splicing, resulting in a larger contact area at the longitudinal joint and higher overall structural rigidity. This effectively suppresses dynamic deformation caused by tower vibration to a certain extent. Furthermore, during on-site hoisting and splicing, the design of the keyway 102 and the raised key 202, through prefabricated concave-convex structures, allows for rapid positioning, reducing manual adjustment time and eliminating the need for high-precision bolt hole alignment. Additionally, the splicing method of this invention reduces the amount of high-strength bolts used, saving steel; moreover, the splicing connection method eliminates the need for regular bolt tightening, provides better sealing, and reduces subsequent maintenance costs.

[0066] Example 4

[0067] This embodiment provides a method for preparing dry-connected UHPC wind turbine tower concrete segments, including:

[0068] S1, pour the connecting strip A as described in Example 1; specifically, arrange the shear reinforcement A in the mold of connecting strip A, then pour ultra-high performance concrete (UHPC) into the mold of connecting strip A, and wait for it to form to obtain the connecting strip A;

[0069] S2, the side of the connecting strip A with the keyway is used as the bottom mold for casting the connecting strip B, and a release agent is applied to the side of the connecting strip A with the keyway, and then the connecting strip B as described in Example 1 is cast; furthermore, before casting the connecting strip B, the shear reinforcement B needs to be arranged in the mold of the connecting strip B in advance, and after the shear reinforcement B is arranged, ultra-high performance concrete is cast into the mold of the connecting strip B.

[0070] S3, the connecting strip B is used as one longitudinal side mold of the main concrete segment mold, the shear reinforcement B is located inside the main concrete segment mold, and the connecting piece A is used as the other longitudinal side mold of the main concrete segment mold, the shear reinforcement A is located inside the main concrete segment mold. Concrete (ordinary concrete) is poured into the main concrete segment mold to obtain the concrete segment. It should be noted that the main concrete segment mold has concrete grouting channels.

[0071] Using the side of the connecting strip A with the keyway as the bottom (bottom mold) of the mold for casting the connecting strip B ensures that the formed convex key and the keyway have a high degree of fit and good bonding, preventing the concrete pipe segments from being locally crushed during assembly due to manufacturing errors, thereby improving the stability of the longitudinal joint of the tower connection.

[0072] Connecting strips A and B are directly used as casting molds for the left and right ends of the concrete segment body, replacing part of the existing casting mold structure. Specifically, shear reinforcement B extends from one side of the concrete segment body mold into the mold, and shear reinforcement A extends from the other side into the mold. Connecting strips A and B respectively close the longitudinal ends of the concrete segment. Then, concrete is poured into the concrete segment body mold, making connecting strips A, B, shear reinforcement A, and B integrally cast with the concrete segment body. This achieves integrated molding of segmented tower concrete segments, resulting in good bonding, faster tower segment splicing, and further improved construction efficiency. Connecting strips A and B replace the two longitudinal side structures of the concrete segment body mold, optimizing the existing casting mold structure design and reducing mold costs.

[0073] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A dry-connection longitudinal joint connection structure for UHPC wind turbine towers, characterized in that, include: A connecting strip A is used as a splicing member at one end of the longitudinal side of the main body of a concrete pipe segment. The connecting strip A is provided with a keyway and a shear reinforcement A. The keyway and the shear reinforcement A are respectively located on two opposite longitudinal sides of the connecting strip A. An extension section A extends from the upper end of the connecting strip A. The width of the extension section A is smaller than the width of the connecting strip A. A connecting strip B serves as a splicing component at the other end of the longitudinal side of the main body of the concrete tunnel segment. The connecting strip B is provided with a key and shear reinforcement B, located on two opposite longitudinal sides of the connecting strip B. An extension section B extends from the upper end of the connecting strip B, with the width of the extension section B being less than the width of the connecting strip B. Both shear reinforcement A and shear reinforcement B are cast inside the longitudinal side of the main body of the concrete tunnel segment. Connecting strip A and connecting strip B are spliced ​​together via the keyway and the key. After splicing, the extension section A and extension section B combine to form a tower section butt block, which is used to fit and insert into the butt groove at the bottom of the main body of the concrete tunnel segment. Connecting strip A and connecting strip B have the same height. The connecting strip A and the connecting strip B are made of UHPC; There are multiple keyways and multiple convex keys, and the multiple keyways and multiple convex keys are spliced ​​together in a one-to-one correspondence; The thickness of both connecting strip A and connecting strip B is 50-100cm; the depth of the keyway is 0.1-0.2 times the thickness of connecting strip A, the length is 0.75-0.85 times the width of connecting strip A, and the distances from both ends of the keyway along its length to the front and rear walls of connecting strip A are equal; the width of the keyway is 0.3-0.5 times its length; and the spacing between the keyways is 1.2-1.4 times its width. The cross-section of the keyway perpendicular to its depth direction is a trapezoidal structure, and the shape of the convex key matches the keyway; Both shear reinforcement A and shear reinforcement B are generally annular structures. One end of shear reinforcement A is perpendicularly connected to connecting strip A, and one end of shear reinforcement B is perpendicularly connected to connecting strip B.

2. The dry-connection longitudinal joint connection structure for UHPC wind turbine towers according to claim 1, characterized in that, There are multiple shear reinforcements A and multiple shear reinforcements B, with the multiple shear reinforcements A and B being parallel to each other.

3. The longitudinal joint connection structure of a dry-connected UHPC wind turbine tower according to claim 2, characterized in that, The keyway corresponds one-to-one with the shear reinforcement A, and the convex key corresponds one-to-one with the shear reinforcement B.

4. A dry-connected UHPC wind turbine tower concrete segment, characterized in that, The structure includes a concrete segment body and a longitudinal joint connection structure as described in any one of claims 1-3. Shear reinforcement A and shear reinforcement B are both located inside the concrete segment body. Connecting strip A has shear reinforcement A on one side and is cast to one end of the shear reinforcement A on the longitudinal side of the concrete segment body. Connecting strip B has shear reinforcement B on one side and is cast to the other end of the shear reinforcement B on the longitudinal side of the concrete segment body. A butt joint groove is provided at the center of the bottom end of the concrete segment body for mating and insertion with the tower section butt joint block.

5. A dry-connected UHPC wind turbine tower, characterized in that, It includes multiple concrete segments as described in claim 4, which are spliced ​​together by the connecting strip A and the connecting strip B to form a tower segment. The multiple tower segments overlap in a staggered manner, and after overlapping, the tower segment docking block is inserted into the docking groove.

6. A method for preparing dry-connected UHPC wind turbine tower concrete segments, characterized in that, The method for preparing the dry-connected UHPC wind turbine tower concrete segments as described in claim 4 includes: S1, Casting connecting strip A; S2, use the side of the connecting strip A with the keyway as the bottom mold for casting the connecting strip B, and cast the connecting strip B; S3, the connecting strip B is used as one longitudinal side mold of the main body mold of the concrete segment, the shear reinforcement B is located inside the main body mold of the concrete segment, the connecting strip A is used as another longitudinal side mold of the main body mold of the concrete segment, the shear reinforcement A is located inside the main body mold of the concrete segment, and concrete is poured into the main body mold of the concrete segment to obtain the concrete segment.

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