Anchor bolt positioning fixtures and methods for steel-concrete lap joint transition sections of wind turbine towers

Abstract

This invention discloses an anchor bolt positioning fixture and method for the steel-concrete lap transition section of a wind turbine tower. The positioning fixture includes a positioning ring assembly, a first calibration stepped pin, a second calibration stepped pin, and an axial positioning bracket for the anchor bolt cage. The positioning ring assembly includes a positioning ring and multiple ring washers. The bottom of the anchor bolt cage is supported on the foundation surface of the concrete tower by multiple evenly distributed axial positioning brackets and steel base rods. The positioning method includes: 1) calibrating the positions of the ring washers and nuts using the first and second calibration stepped pins respectively; 2) assembling the anchor bolt cage and installing the positioning ring assembly, then hoisting and positioning the anchor bolt cage in the steel reinforcement cage of the concrete tower; 3) verifying the exposed dimensions of the upper end of the anchor bolt extending beyond the positioning ring assembly before pouring concrete. This invention significantly improves the installation accuracy of the fixed connection between the steel structure tower and the concrete tower of the wind turbine tower, shortens the anchor bolt pre-embedding time, and effectively improves installation efficiency.

Description

Technical Field

[0001] This invention relates to a positioning device for the connection of pre-embedded bolts in concrete structures and steel structures, and particularly to a precise positioning device and method for pre-embedded bolts in wind power generation concrete towers that facilitate connection with steel structure towers, belonging to the field of construction technology for precast concrete tubular components. Background Technology

[0002] Wind power generation utilizes inexhaustible wind resources and is a high-quality, green, and renewable energy source that reduces environmental pollution. In recent years, wind power generation has been widely promoted and applied. Existing wind turbine towers generally use an all-steel structure. To reduce construction costs, when the tower height exceeds 110m, a combined structure with a concrete base and a steel top can significantly reduce the manufacturing cost of the wind turbine. For example... Figure 1 and Figure 2 As shown, the transition section of a wind turbine hybrid tower in a certain wind farm requires the pre-embedding of an anchor cage 100, which is composed of an upper anchor plate 10, a lower anchor plate 20, and 92 anchor bolts 30 fixedly connected by nuts 402. A ring of 92 anchor bolts 30 extending from the top of the anchor cage 100 is fixedly connected to the bottom flange 401 of the steel structure tower 40 by nuts 402, thus forming the steel-concrete hybrid tower body 200 of the wind turbine. During the design, the influence of vibration and displacement of the steel structure tower 40 above the tower body 200 under irregular wind direction and wind force was considered. A ring of 92 mounting holes 403 are densely and evenly distributed on the distribution circle with a diameter of Φ4534mm on the bottom flange 401 of the steel structure tower 40. The difference between the diameter of the mounting hole 403 and the outer diameter of the upper end of the anchor bolt 30 is only 4mm, and the included angle between two adjacent mounting holes 403 is only 3.9°. How to reduce the coaxiality deviation between the 92 anchor bolts 30 and the mounting holes 403, and ensure that all 92 anchor bolts 30 can be accurately inserted into the mounting holes 403 of the bottom flange 401 of the steel structure tower 40, is a major challenge in the construction of steel-concrete lap joints for wind turbines. Summary of the Invention

[0003] The purpose of this invention is to provide a positioning anchor bolt positioning tool and method for the steel-concrete lap joint transition section of a wind turbine tower, solving a major problem in the construction of steel-concrete lap joints of wind turbine generators.

[0004] This invention is achieved through the following technical solution:

[0005] An anchor bolt positioning fixture for a steel-concrete lap transition section of a wind turbine tower includes a positioning ring assembly, a first calibration stepped pin, a second calibration stepped pin, and an axial positioning bracket for the anchor bolt cage. The positioning ring assembly includes a positioning ring and multiple ring gaskets. Multiple through holes are evenly distributed on the positioning ring. The diameter D1 of the through holes of the positioning ring matches the outer diameter d1 of the large end of the first calibration stepped pin, and the diameter D2 of the inner hole of the ring gasket matches the outer diameter d2 of the small end of the first calibration stepped pin. The ring gaskets are positioned on the positioning ring and spot-welded by inserting the first calibration stepped pins into the through holes of the positioning ring and the inner holes of the ring gaskets. The diameter D3 of the through hole of the lower anchor plate matches the outer diameter d3 of the large end of the second calibration step pin. The diameter D4 of the bottom hole of the nut, which is welded and fixed to the lower side of the through hole of the lower anchor plate, matches the outer diameter d4 of the small end of the second calibration step pin. The bottom of the anchor cage, which is assembled from the upper anchor plate, the lower anchor plate, multiple anchor bolts and nuts at both ends of the anchor bolts, is supported on the foundation bottom of the concrete tower by multiple evenly distributed anchor cage axial positioning brackets and horizontally placed steel base rods. The upper end of the anchor bolt passes through the upper anchor plate at the top of the anchor cage from bottom to top, and then passes through the through hole of the positioning ring and the inner hole of the ring washer in sequence, so as to calibrate the anchor bolt through the inner hole of the ring washer on the positioning ring.

[0006] The objectives of this invention can also be further achieved through the following technical measures.

[0007] Furthermore, the axial positioning bracket of the anchor cage is welded from structural steel and includes two uprights and several horizontal bars spaced apart vertically. The horizontal bars are located between the two uprights, and both ends of the horizontal bars are welded and fixed to the uprights respectively. The multiple anchor cage axial positioning brackets are arranged radially and evenly with the center of the bottom surface of the concrete tower foundation as the center. The lower anchor plate at the bottom of the anchor cage is supported on the top surface of the uprights of the multiple anchor cage axial positioning brackets. The bottom of the anchor cage axial positioning bracket is supported on the bottom surface of the concrete tower foundation by a horizontally placed structural steel base rod.

[0008] Furthermore, the differences between the through hole diameter D1 of the positioning ring and the outer diameter d1 of the large end of the first calibration stepped pin, the differences between the inner hole diameter D2 of the ring washer and the outer diameter d2 of the small end of the first calibration stepped pin, the differences between the through hole diameter D3 of the lower anchor plate and the outer diameter d3 of the large end of the second calibration stepped pin, and the differences between the bottom hole diameter D4 of the nut on the lower side of the through hole of the lower anchor plate and the outer diameter d4 of the small end of the second calibration stepped pin are all 0.4 to 0.6 mm.

[0009] A positioning method for a positioning anchor bolt positioning fixture in a steel-concrete lap transition section of a wind turbine tower includes the following steps:

[0010] 1) Pass the first calibration step pin with the large end facing down through the through hole of the positioning ring, then put the ring washer on the small end of the first calibration step pin so that the ring washer is positioned on the upper side of the through hole of the positioning ring, and then spot weld the ring washer to the positioning ring; repeat the above process several times to position and fix the ring washer to the corresponding through hole of the positioning ring one by one, and complete the fabrication of the positioning ring assembly;

[0011] 2) Pass the second calibration step pin through the lower anchor plate through hole with the large end facing upwards, and pass the second calibration step pin through the threaded bottom hole of the nut that is already abutting against the lower anchor plate through hole, so that the nut is accurately positioned on the outside of the lower anchor plate through hole and welded and fixed; repeat the above process multiple times to position and weld the nuts to the lower side of the corresponding lower anchor plate through hole one by one.

[0012] 3) Divide a portion of the anchors into groups, with each group of several anchors evenly distributed adjacent to each other on the lower anchor plate. The lower ends of the anchors pass through the corresponding through holes in the lower anchor plate and are screwed into the nuts, with the lower ends of the anchors extending out of the lower side of the nuts. Then, attach the anti-corrosion sleeve, which is open at the top and closed at the bottom, to the lower end of the anchors and the outside of the nuts. The upper end of the anti-corrosion sleeve is welded and fixed to the lower side of the lower anchor plate.

[0013] 4) Screw the nylon nut onto the upper end of the anchor bolt. Determine the height position of the nylon nut at the upper end of the anchor bolt according to the design length of the upper end of the anchor bolt extending beyond the upper anchor plate. Then, fit the through hole of the upper anchor plate into the upper end of the corresponding anchor bolt, so that the upper anchor plate is supported on the corresponding nylon nut.

[0014] 5) Place the ring washer of the positioning ring assembly onto the upper anchor plate with the ring washer facing upwards, so that the upper end of the anchor bolt passes through the through hole of the corresponding positioning ring and the ring washer in sequence from bottom to top. Then tighten the nuts on the upper end of each positioning anchor bolt so that the nuts press against the ring washer on the upper side of the positioning ring assembly.

[0015] 6) Repeat steps 3) to 5) multiple times for the remaining anchor bolts to complete the fabrication of the anchor bolt reinforcement cage and the installation of the positioning ring welding assembly;

[0016] 7) The bottom of the multiple radially evenly arranged anchor cage axial positioning brackets is supported on the bottom surface of the concrete tower foundation by steel bottom rods. Then the anchor steel cage is hoisted into the concrete tower steel cage so that the bottom of the anchor steel cage is supported on the multiple anchor cage axial positioning brackets.

[0017] 8) Use a horizontal laser gauge to measure the exposed dimensions of the anchor bolt extending beyond the positioning ring assembly, and verify whether the exposed dimensions meet the design requirements. If the exposed dimensions are correct, proceed with the pouring of the concrete tower. If there are errors in the exposed dimensions, use pipe wrenches to rotate the anchor bolt to adjust the exposed length of the anchor bolt to meet the requirements before pouring the concrete.

[0018] 9) After the concrete has been steam-cured, remove the nuts and the positioning ring assembly. Roughen the joint surface between the positioning ring assembly and the upper anchor plate. Then fix the positioning ring assembly back onto the upper side of the upper anchor plate. Next, perform grouting to prevent the anchor from shifting due to the expansion and compression of the anchor during grouting, thus achieving secondary precise positioning of the anchor.

[0019] 10) After grouting is completed, steam curing is carried out. After steam curing is completed, the nut and positioning ring assembly are removed.

[0020] The first and second calibration stepped pins of the coaxial structure of this invention are used to calibrate the coaxiality of the inner hole of the circular washer and the through hole of the positioning ring, as well as the coaxiality of the through hole of the lower anchor plate and the threaded bottom hole of the nut. This improves the assembly accuracy of the anchor cage, ensuring that the heads of the densely distributed anchors can be accurately inserted into the mounting holes at the bottom of the steel structure tower. This invention avoids the drawback of conventional anchor positioning fixtures where anchors deform or shift due to impact during concrete tower pouring, preventing them from being fixedly connected to the bottom of the steel structure tower. The anchor positioning fixture of this invention has a simple structure and a convenient anchor positioning method, significantly improving the installation accuracy of the fixed connection between the steel structure tower and the concrete tower in the steel-concrete lap transition section of the wind turbine tower, shortening the anchor pre-embedding time, and effectively improving installation efficiency.

[0021] The advantages and features of the present invention will be illustrated and explained by the following non-limiting description of preferred embodiments, which are given by way of example only with reference to the accompanying drawings. Attached Figure Description

[0022] Figure 1 This is a schematic diagram showing the anchor bolt steel cage with the positioning ring assembly welded at the top positioned in the concrete tower steel cage.

[0023] Figure 2 This is a schematic diagram showing the fixed connection between the steel structure tower and the concrete tower of the transition section of the wind power hybrid tower;

[0024] Figure 3 This is the front view of the positioning ring assembly;

[0025] Figure 4 This is a schematic diagram showing the use of the first calibration step pin to position the inner hole of the annular gasket and spot weld it to the upper side of the through hole of the positioning annular ring;

[0026] Figure 5 This is a schematic diagram showing the use of the second calibration step pin to position the bottom hole of the nut and weld it to the lower side of the through hole of the lower anchor plate. Detailed Implementation

[0027] The invention will be further described below with reference to the accompanying drawings and an embodiment of a wind power tower combining concrete and steel structures at the Longjiang County Wind Power Plant in Qiqihar City.

[0028] like Figures 1-5 As shown, this embodiment includes a positioning ring assembly 1, a first calibration step pin 2, a second calibration step pin 3, and an axial positioning bracket for the anchor bolt cage 4. The positioning ring assembly 1 includes a positioning ring 11 and 92 ring gaskets 12. In this embodiment, the positioning ring 1 has an outer diameter of 5000mm, an inner diameter of 4300mm, and a thickness of 50mm. The positioning ring 11 has 92 through holes 111 with a diameter of 54mm evenly distributed on it. The positioning ring 11 weighs 1924kg. The large mass of the positioning ring assembly 1 can effectively prevent the upper anchor plate 10 from arching and floating under the expansion force of the grouting layer, ensuring that the anchor bolt 30 is accurately positioned, which is beneficial for docking with the steel structure tower 40. The through-hole diameter D1 of the positioning ring 11 matches the outer diameter d1 of the large end of the first calibration stepped pin, and the inner hole diameter D2 of the ring washer matches the outer diameter d2 of the small end of the first calibration stepped pin. The ring washer 12 is positioned on the positioning ring 11 by inserting the first calibration stepped pin 2 into the through-hole 111 of the positioning ring 11 and the inner hole 121 of the ring washer, and then spot-welded to secure it. The through-hole diameter D3 of the lower anchor plate matches the outer diameter d3 of the large end of the second calibration stepped pin, and the bottom hole diameter D4 of the nut, welded and fixed to the lower side of the through-hole 201 of the lower anchor plate, matches the outer diameter d4 of the small end of the second calibration stepped pin.

[0029] The anchor cage 100, which is assembled from the upper anchor plate 10, the lower anchor plate 20, 92 anchor bolts 30 and nuts 402 at both ends of the anchor bolts 30, is supported at the bottom of the concrete tower 200 foundation by multiple evenly distributed anchor cage axial positioning brackets 4 and horizontally placed steel base rods 5. The upper end of the anchor bolt 30 first passes through the upper anchor plate 10 at the top of the anchor cage 100 from bottom to top, and then passes through the through hole 111 of the positioning ring 11 and the inner hole 121 of the ring washer in sequence, so that the anchor bolt 30 is calibrated by the inner hole 121 of the ring washer on the positioning ring 11.

[0030] The anchor cage axial positioning bracket 4 is welded from square steel tubes and includes two uprights 41 and several horizontal bars 42 spaced apart vertically. The horizontal bars 42 are located between the two uprights 41, and both ends of the horizontal bars 42 are welded and fixed to the uprights 41 respectively. The multiple anchor cage axial positioning brackets 4 are arranged radially and evenly with the center of the foundation bottom surface of the concrete tower 200 as the center. The lower anchor plate 20 at the bottom of the anchor cage 100 is supported on the top surface of the uprights 41 of the multiple anchor cage axial positioning brackets 4. The bottom of the anchor cage axial positioning bracket 4 is supported on the foundation bottom surface 210 of the concrete tower 200 by a horizontally placed steel base rod 5.

[0031] The differences between the through hole diameter D1 of the positioning ring 11 and the outer diameter d1 of the large end of the first calibration stepped pin, the differences between the inner hole diameter D2 of the ring washer 12 and the outer diameter d2 of the small end of the first calibration stepped pin, the differences between the through hole diameter D3 of the lower anchor plate and the outer diameter d3 of the large end of the second calibration stepped pin, and the differences between the bottom hole diameter D4 of the nut on the lower side of the through hole 201 of the lower anchor plate and the outer diameter d4 of the small end of the second calibration stepped pin are all 0.5mm. The smaller gap between the first calibration stepped pin 2 and the inner hole 121 of the ring washer improves the coaxiality between the inner hole 121 of the ring washer and the through hole 111 of the positioning ring 11; the smaller gap between the second calibration stepped pin 3 and the bottom hole 404 of the nut improves the coaxiality between the bottom hole 404 of the nut and the through hole 201 of the lower anchor plate; thereby improving the reliability of the upper end of the crossbar 42 fitting into the mounting hole 403 of the steel structure tower 40.

[0032] A positioning method for a positioning anchor bolt positioning fixture in a steel-concrete lap transition section of a wind turbine tower includes the following steps:

[0033] 1) Pass the first calibration stepped pin 2, with its large end facing down, through the through hole 111 of the positioning ring 11. Then, fit the ring washer 12 onto the small end of the first calibration stepped pin 2. Position the ring washer 12 one by one onto the corresponding through hole 111 of the positioning ring 11. Finally, spot weld the ring washer 12 onto the positioning ring 11. Repeat the above process multiple times to position and fix the ring washer 12 one by one onto the corresponding through hole 111 of the positioning ring 11, thus completing the fabrication of the positioning ring assembly 1.

[0034] 2) Pass the second calibration step pin 3, with its large end facing upwards, through the lower anchor plate through hole 201. Pass the small end of the second calibration step pin 3 through the threaded bottom hole 404 of the nut 402, which is already abutting against the lower anchor plate through hole 201, so that the nut 402 is precisely positioned on the outside of the lower anchor plate through hole 201 and welded in place. Repeat the above process multiple times, positioning and welding each nut 402 to the lower side of the corresponding lower anchor plate through hole 201.

[0035] 3) Divide a portion of the anchor bolts 30 into groups, with several anchor bolts 30 in each group evenly distributed adjacently on the lower anchor plate 20. The lower ends of the anchor bolts 30 pass through the corresponding through holes 201 in the lower anchor plate and are screwed into the nuts 402, with the lower ends of the anchor bolts 30 extending beyond the lower side of the nuts 402. Then, attach the anti-corrosion sleeve 301, which is open at the top and closed at the bottom, to the lower end of the anchor bolts 30 and the outside of the nuts 402. The upper end of the anti-corrosion sleeve 301 is welded and fixed to the lower side of the lower anchor plate 20.

[0036] 4) Screw the nylon nut 302 onto the upper end of the anchor bolt 30. Determine the height position of the nylon nut 302 at the upper end of the anchor bolt 30 according to the design length of the upper end of the anchor bolt 30 extending beyond the upper anchor plate 10. Then, fit the upper anchor plate through hole 101 onto the upper end of the corresponding anchor bolt 30, so that the upper anchor plate 10 is supported on the corresponding nylon nut 302.

[0037] 5) Place the annular washer 12 of the positioning annular assembly 1 onto the upper anchor plate 10 with the orientation facing upward, so that the upper end of the anchor bolt 30 passes through the through hole 111 of the corresponding positioning annular ring 11 and the annular washer 12 from bottom to top. Then tighten the nut 402 onto the upper end of each positioning anchor bolt 30, so that the nut 402 presses against the annular washer 12 on the upper side of the positioning annular assembly 1.

[0038] 6) Repeat steps 3) to 5) more than 30 times with the remaining anchor bolts to complete the fabrication of the anchor bolt steel cage 100 and the installation of the positioning ring welded component 1.

[0039] 7) The bottom of the multiple radially evenly arranged anchor cage axial positioning brackets 4 is supported on the foundation bottom surface 210 of the concrete tower 200 by steel base rods 5. Then the anchor steel cage 100 is hoisted into the concrete tower steel cage 201, so that the bottom of the anchor steel cage 100 is supported on the multiple anchor cage axial positioning brackets 4.

[0040] 8) Use a horizontal laser instrument to measure the exposed dimensions of the upper end of the anchor bolt 30 extending out of the positioning ring welded part 1, and check whether the exposed dimensions meet the design requirements: if the exposed dimensions are correct, then pour the concrete tower 200; if the exposed dimensions are incorrect, use pipe wrenches to rotate the anchor bolt 30 to adjust the exposed length of the anchor bolt 30 to meet the requirements before pouring the concrete.

[0041] 9) After the concrete steam curing is completed, remove the nut 402 and the positioning ring assembly 1 respectively. Roughen the joint surface of the positioning ring assembly 1 and the upper anchor plate 10. Then fix the positioning ring assembly 1 back on the upper side of the upper anchor plate 10. Then carry out the grouting operation to avoid the expansion of the grouting material during the grouting process, which would cause the anchor bolt 30 to shift, and achieve the secondary precise positioning of the anchor bolt 30.

[0042] 10) After grouting is completed, steam curing is carried out. After steam curing is completed, the nut and positioning ring assembly are removed.

[0043] In addition to the above embodiments, the present invention may have other implementation methods. All technical solutions formed by equivalent substitution or equivalent transformation fall within the protection scope claimed by the present invention.

Claims

1. A bolt positioning fixture for a steel-concrete lap joint transition section of a wind turbine tower, characterized in that, The system includes a positioning ring assembly, a first calibration stepped pin, a second calibration stepped pin, and an axial positioning bracket for the anchor cage. The positioning ring assembly comprises a positioning ring and multiple ring gaskets. Multiple through holes are evenly distributed on the positioning ring. The diameter D1 of the through holes in the positioning ring matches the outer diameter d1 of the large end of the first calibration stepped pin, and the diameter D2 of the inner holes in the ring gaskets matches the outer diameter d2 of the small end of the first calibration stepped pin. The ring gaskets are positioned on the positioning ring and spot-welded in place by inserting the first calibration stepped pins into the through holes of the positioning ring and the inner holes of the ring gaskets. The diameter D3 of the through holes in the lower anchor plate is... The outer diameter d3 of the large end of the second calibration step pin is matched with the bottom hole diameter D4 of the nut welded and fixed to the lower side of the through hole of the lower anchor plate, which is matched with the outer diameter d4 of the small end of the second calibration step pin. The bottom of the anchor cage, which is assembled from the upper anchor plate, the lower anchor plate, multiple anchor bolts and nuts at both ends of the anchor bolts, is supported on the foundation bottom of the concrete tower by multiple evenly distributed anchor cage axial positioning brackets and horizontally placed steel bottom rods. The upper end of the anchor bolt passes through the upper anchor plate at the top of the anchor cage from bottom to top, and then passes through the through hole of the positioning ring and the ring washer in sequence, so as to calibrate the anchor bolt through the inner hole of the ring washer on the positioning ring. The anchor cage axial positioning bracket is welded from structural steel and includes two uprights and several horizontal bars spaced apart vertically. The horizontal bars are located between the two uprights, and both ends of the horizontal bars are welded and fixed to the uprights. The multiple anchor cage axial positioning brackets are arranged radially and evenly with the center of the concrete tower foundation bottom surface as the center. The lower anchor plate at the bottom of the anchor cage is supported on the top surface of the uprights of the multiple anchor cage axial positioning brackets. The bottom of the anchor cage axial positioning bracket is supported on the concrete tower foundation bottom surface by a horizontally placed structural steel base rod.

2. The anchor bolt positioning fixture for the steel-concrete lap joint transition section of the wind turbine tower as described in claim 1, characterized in that, The differences between the through hole diameter D1 of the positioning ring and the outer diameter d1 of the large end of the first calibration stepped pin, the differences between the inner hole diameter D2 of the ring washer and the outer diameter d2 of the small end of the first calibration stepped pin, the differences between the through hole diameter D3 of the lower anchor plate and the outer diameter d3 of the large end of the second calibration stepped pin, and the differences between the bottom hole diameter D4 of the nut on the lower side of the through hole of the lower anchor plate and the outer diameter d4 of the small end of the second calibration stepped pin are all 0.4 to 0.6 mm.

3. A positioning method for the anchor bolt positioning fixture of the steel-concrete lap transition section of a wind turbine tower as described in claim 1, characterized in that, Includes the following steps: 1) Pass the first calibration step pin with the large end facing down through the through hole of the positioning ring, then put the ring washer on the small end of the first calibration step pin, so that the ring washer is positioned on the upper side of the through hole of the positioning ring, and then spot weld the ring washer to the positioning ring; repeat the above process several times, and position and fix the ring washer to the corresponding through hole of the positioning ring one by one to complete the fabrication of the positioning ring assembly; 2) Pass the second calibration step pin through the lower anchor plate through hole with the large end facing upwards, and pass the second calibration step pin through the threaded bottom hole of the nut that is already abutting against the lower anchor plate through hole, so that the nut is accurately positioned on the outside of the lower anchor plate through hole and welded and fixed; repeat the above process multiple times to position and weld the nuts to the lower side of the corresponding lower anchor plate through hole one by one. 3) Divide a portion of the anchors into groups, with several anchors in each group evenly distributed adjacent to each other on the lower anchor plate. The lower ends of the anchors pass through the corresponding through holes in the lower anchor plate and are screwed into the nuts, with the lower ends of the anchors extending out of the lower side of the nuts. Then, attach the anti-corrosion sleeve, which is open at the top and closed at the bottom, to the lower end of the anchors and the outside of the nuts. The upper end of the anti-corrosion sleeve is welded and fixed to the lower side of the lower anchor plate. 4) Screw the nylon nut onto the upper end of the anchor bolt. Determine the height position of the nylon nut at the upper end of the anchor bolt according to the design length of the upper end of the anchor bolt extending beyond the upper anchor plate. Then, fit the through hole of the upper anchor plate into the upper end of the corresponding anchor bolt, so that the upper anchor plate is supported on the corresponding nylon nut. 5) Place the ring washer of the positioning ring assembly onto the upper anchor plate with the ring facing upward, so that the upper end of the anchor bolt passes through the through hole of the corresponding positioning ring and the ring washer from bottom to top. Then tighten the nuts on the upper end of each positioning anchor bolt so that the nuts press against the ring washer on the upper side of the positioning ring assembly. 6) Repeat steps 3) to 5) multiple times for the remaining anchor bolts to complete the fabrication of the anchor bolt reinforcement cage and the installation of the positioning ring welded assembly; 7) The bottom of the multiple radially evenly arranged anchor cage axial positioning brackets is supported on the bottom surface of the concrete tower foundation by steel bottom rods. Then the anchor steel cage is hoisted into the concrete tower steel cage, so that the bottom of the anchor steel cage is supported on the multiple anchor cage axial positioning brackets. 8) Use a horizontal laser gauge to measure the exposed dimensions of the anchor bolt extending beyond the positioning ring assembly, and verify whether the exposed dimensions meet the design requirements. If the exposed dimensions are correct, proceed with the pouring of the concrete tower. If there are errors in the exposed dimensions, use pipe wrenches to rotate the anchor bolt to adjust the exposed length of the anchor bolt to meet the requirements before pouring the concrete. 9) After the concrete has been steam-cured, remove the nuts and the positioning ring assembly. Roughen the joint surface between the positioning ring assembly and the upper anchor plate. Then fix the positioning ring assembly back onto the upper side of the upper anchor plate. Next, perform grouting to prevent the positioning anchor from shifting due to the expansion and compression of the grout during grouting. This will achieve secondary precise positioning of the anchor. 10) After grouting is completed, steam curing is carried out. After steam curing is completed, the nut and positioning ring assembly are removed.

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