Overlapped prestressed concrete filled steel tube wind power tower corner post and construction method

Abstract

The invention belongs to the technical field of wind power generation, and discloses a superposed prestressed concrete filled steel tube wind power tower corner post and a construction method, the superposed prestressed concrete filled steel tube wind power tower corner post comprises a corner post steel tube, a prestressed hollow pile is sleeved in the corner post steel tube, and a bonding gap between the corner post steel tube and the prestressed hollow pile is filled with a cementing material added with an expanding agent; stiffening ribs or studs are fixedly connected to the inner wall of the corner column steel pipe, and a plurality of anti-shear grooves are pre-formed in the outer wall of the prestressed hollow pile; hubbed flanges are fixedly connected to the upper end and the lower end of the corner post, the hubbed flange at the lower end is fixedly welded with the corner post steel pipe, and the hubbed flange at the upper end is fixedly welded with the corner post steel pipe after the prestressed hollow pile is put into the corner post steel pipe; the hubbed flanges are fixedly connected with the top end and the bottom end of the prestressed hollow pile, a plurality of grout outlet holes are evenly formed in the hubbed flange at the upper end, a plurality of grouting holes are formed in the bottom end of the corner column steel pipe, and grouting is conducted from bottom to top at the bottom end of the corner column steel pipe. Redundant time of concrete curing is eliminated, and compactness and structural integrity of combined gaps are guaranteed.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of wind power generation, and particularly relates to a laminated prestressed concrete filled steel tube wind power tower corner column and a construction method. BACKGROUND

[0002] The statements in this section merely provide background information related to the present application and do not necessarily constitute prior art.

[0003] With the continuous development and progress of wind power generation technology, the steel pipe concrete lattice tower structure is widely used in the field of wind power generation due to its large space stiffness and excellent structural dynamic characteristics; the steel pipe concrete lattice tower structure supplemented by prestress can further improve its fatigue resistance and is more suitable for the reciprocating load environment of wind power generation.

[0004] A prestressed hollow sandwich steel pipe concrete lattice hybrid tower disclosed in the prior art comprises a lattice tower and a foundation, and the corner columns of the lattice tower are connected to the embedded parts in the foundation through bolts; the corner columns are all hollow sandwich steel pipe concrete, and the hollow part is a tensioned prestressed tendon channel.

[0005] The above scheme can reduce the amount of steel used, but still has some defects: The corner column of the above scheme adopts hollow sandwich steel pipe concrete, which is formed by pouring concrete between the inner steel pipe and the outer steel pipe and then curing, which leads to a long overall preparation period of the hollow sandwich steel pipe concrete; in addition, when pouring concrete between the inner steel pipe and the outer steel pipe, the presence of bubbles or insufficient flow of concrete can also lead to incomplete filling, which reduces the interfacial bonding strength and affects the overall stability and fatigue resistance of the structure. SUMMARY

[0006] Therefore, the present application aims to provide a laminated prestressed concrete filled steel tube wind power tower corner column and a construction method, which can solve the technical problems of long preparation time and incomplete filling of the corner column in the prior art.

[0007] To achieve the above-mentioned purpose, the present application adopts the following technical solutions: In a first aspect, a laminated prestressed concrete filled steel tube wind power tower corner column is provided, which comprises a corner steel pipe, a finished prestressed hollow pile is sleeved in the corner steel pipe, a combined gap is formed between the corner steel pipe and the prestressed hollow pile, and a cementing material added with an expanding agent is filled in the combined gap; A stiffening rib or a stud is fixedly connected to the inner wall of the corner steel pipe, and a plurality of shear grooves are pre-set on the outer wall of the prestressed hollow pile; The upper and lower ends of the corner column are fixedly connected with necked flanges. The lower necked flange is welded and fixed to the corner column steel pipe, and the upper necked flange is welded and fixed to the corner column steel pipe after the prestressed hollow pile is put into the corner column steel pipe. The neck flange is fixedly connected to the top and bottom of the prestressed hollow pile. Multiple grout outlet holes are evenly opened on the upper neck flange, and multiple grout injection holes are opened at the bottom of the corner column steel pipe. Grouting is performed from the bottom to the top of the corner column steel pipe.

[0008] Preferably, the neck flange includes a flange plate, one side of which is fixedly connected to an inner ring plate and an outer ring plate. The outer diameter of the inner ring plate is equal to the inner diameter of the prestressed hollow pile, the diameter of the outer ring plate is equal to the diameter of the corner column steel pipe, and the wall thickness of the outer ring plate is equal to the wall thickness of the corner column steel pipe.

[0009] Preferably, the slurry outlet is located on the flange between the inner ring plate and the outer ring plate, and the slurry outlet is located above the joint gap; a number of flange bolt holes are also evenly provided on the flange on the outer side of the outer ring plate.

[0010] Preferably, several horizontally placed threaded sleeves are uniformly embedded in the inner circumferential direction of the top and bottom of the prestressed hollow pile, and locking bolt holes corresponding to the threaded sleeves are also opened on the inner ring plate, and the threaded sleeves are threadedly connected to the locking bolts.

[0011] Preferably, the corner column steel pipe and the prestressed hollow pile are reinforced with an alignment member for coaxial alignment; the alignment member includes an alignment groove on the inner wall of the corner column steel pipe, which is surrounded by two longitudinal stiffening ribs, and also includes an alignment plate embedded in the outer wall of the prestressed hollow pile. The alignment plate is a T-shaped plate, with its horizontal plate embedded in the prestressed hollow pile and its vertical plate extending out of the prestressed hollow pile and inserted into the alignment groove.

[0012] Preferably, the radial length of the stiffening rib is less than the radial length of the joint gap, the radial length of the vertical plate on the outer wall of the prestressed hollow pile is less than the radial length of the joint gap, and opposite limiting plates are welded on both sides of the vertical plate, with the limiting plates abutting against the stiffening rib.

[0013] Preferably, the depth of the shear groove is 1-3 cm and the spacing between the shear grooves is 10-20 cm.

[0014] Preferably, the connection between the prestressed hollow pile and the corner column steel pipe requires the use of a production frame. The production frame includes four frame columns, with crossbeams fixedly connected to the upper, middle and lower ends of the frame columns. Multiple hoop rings are set at the center of the production frame, with the diameter of the hoop rings equal to the outer diameter of the neck flange. The hoop rings are fixedly connected to the frame columns by inclined beams.

[0015] Preferably, the outer wall of the corner steel pipe is fixedly connected to the connection node of the wind turbine tower inclined column or crossbar.

[0016] Secondly, a construction method for the aforementioned composite prestressed steel-concrete composite wind turbine tower corner column is provided, with the specific steps as follows: Prestressed hollow piles are fabricated in the prefabrication yard, and corner steel pipes and necked flanges are fabricated in the processing yard. Necked flanges are welded to the bottom of the corner steel pipes. Place the corner column steel pipe into the hoop of the production frame, then hoist the prestressed hollow pile into the corner column steel pipe, so that the alignment plate is inserted into the alignment groove. Then install the upper neck flange on the top of the corner column steel pipe and the prestressed hollow pile. Use locking bolts to connect the inner ring plate to the prestressed hollow pile, and then weld the outer ring plate to the corner column steel pipe for fixation. Finally, a bonding material with an expansion agent is injected into the grouting hole at the bottom of the corner column steel pipe until grout comes out of the outlet hole; after curing, the corner column is produced.

[0017] Compared with the prior art, the advantages and positive effects of this invention are: This invention employs precast prestressed hollow piles embedded within corner column steel pipes, using a bonding material with added expansion agent to fill the gap between the prestressed hollow piles and the corner column steel pipes from bottom to top. This solves the problem of insufficient filling caused by air bubbles or inadequate concrete flow when pouring concrete between the inner and outer steel pipes in existing technologies. The application of prestressed hollow piles eliminates redundant time for concrete curing. The synergistic effect of shear grooves and studs, the bottom-to-top grouting flow path design, and the filling compensation mechanism of the expansion agent jointly ensure the compactness of the bonding gaps and the overall structural integrity, thereby improving the strength, reliability, and construction efficiency of wind turbine tower corner columns, saving construction time while ensuring quality, and also saving material on the inner steel pipes. Attached Figure Description

[0018] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0019] Figure 1 This is a cross-sectional view of a corner column of a composite prestressed steel tube concrete wind turbine tower according to Embodiment 1 or Embodiment 2 of the present invention; Figure 2 This is a top view of a composite prestressed steel-concrete composite wind turbine tower corner column according to Embodiment 1 or Embodiment 2 of the present invention; Figure 3 This is an assembly cross-sectional view of the corner column steel pipe and prestressed hollow pile of Embodiment 1 or Embodiment 2 of the present invention; Figure 4 This is a top view of the necked flange of Embodiment 1 or Embodiment 2 of the present invention; Figure 5 This is a cross-sectional view of the necked flange of Embodiment 1 or Embodiment 2 of the present invention; Figure 6 This is a top view of the production stand of Embodiment 1 or Embodiment 2 of the present invention; Figure 7 This is a perspective view of a corner column of a composite prestressed steel-concrete composite wind turbine tower according to Embodiment 1 or Embodiment 2 of the present invention; In the picture: 1. Angle column steel pipe; 11. Stiffening rib; 12. Stud; 13. Grouting hole; 14. Alignment groove; 2. Prestressed hollow pile; 21. Shear groove; 22. Threaded sleeve; 23. Alignment plate; 24. Limiting plate; 25. Locking bolt; 3. Adhesive material; 4. Neck flange; 41. Flange; 42. Inner ring plate; 43. Outer ring plate; 44. Grout outlet hole; 45. Flange bolt hole; 46. Locking bolt hole; 5. Production stand; 51. Frame column; 52. Horizontal beam; 53. Hoop; 54. Inclined beam; 6. Connection node. Detailed Implementation

[0020] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0021] The present invention will now be described in detail with reference to the accompanying drawings.

[0022] Example 1 This embodiment discloses a composite prestressed steel-concrete composite wind turbine tower corner column, such as... Figure 1 , Figure 2 As shown, it includes a corner steel pipe 1 and a prestressed hollow pile 2. The outer diameter of the prestressed hollow pile 2 is smaller than the inner diameter of the corner steel pipe 1. The inner wall of the corner steel pipe 1 is fixedly connected with stiffening ribs 11 or studs 12. The outer wall of the prestressed hollow pile 2 has several shear grooves 21. The joint gap between the corner steel pipe 1 and the prestressed hollow pile 2 is filled with an adhesive material 3 that plays a bonding role.

[0023] It should be noted that the prestressed hollow pile 2 is a pre-manufactured hollow column with prestress, thus avoiding the long waiting time for on-site concrete pouring and preventing incomplete filling during on-site pouring. The inner wall of the corner column steel pipe 1 is fixedly connected with stiffening ribs 11 or studs 12 to enhance the interfacial bonding force and shear resistance between the corner column steel pipe 1 and the bonding material 3. The outer wall of the prestressed hollow pile 2 has several pre-set shear grooves 21. These shear grooves 21 are rectangular cross-section grooves, directly formed on the outer wall surface during the prefabrication of the prestressed hollow pile 2. This improves the bonding performance between the prestressed hollow pile 2 and the bonding material 3, and also forms shear keys within the shear grooves 21 to increase shear resistance. In this embodiment, the studs 12 are cylindrical head weld studs. The outer diameter of the prestressed hollow pile 2 is 80%–90% of the inner diameter of the corner column steel pipe 1, leaving a gap for the connection between the prestressed hollow pile 2 and the corner column steel pipe 1.

[0024] In this embodiment, the bonding material 3 is a high-strength grout or epoxy adhesive, with an expansion agent added to fill the bonding gaps. The high-strength grout can be a cement-based non-shrink grout, the epoxy adhesive can be a two-component epoxy resin system, and the expansion agent can be a calcium oxide-based expansion agent. This causes the bonding material to expand moderately during curing, filling the bonding gaps. The grout has a short curing time; for example, it can reach the required strength in a short time under normal temperature conditions, thus saving the overall manufacturing cycle.

[0025] The prestressed hollow pile 2 is a prefabricated column, and the curing time of the cementitious material 3 is short. Pouring the cementitious material 3 between the corner column steel pipe 1 and the prestressed hollow pile 2 can save construction time for the corner column. This embodiment, through the combination of the prefabricated prestressed hollow pile 2 and the corner column steel pipe 1 with the cementitious material 3, avoids the on-site concrete pouring and curing process, solving the problem of long corner column preparation cycles. Simultaneously, through the shear groove design, the setting of stiffening ribs or studs, and the use of an expansion agent, the compactness of the cementitious material 3 is ensured, effectively preventing the occurrence of incomplete filling.

[0026] like Figure 1 , Figure 3 As shown, the upper and lower end faces of the corner column are fixedly connected with necked flanges 4. The lower necked flange 4 is welded and fixed to the corner column steel pipe 1. The upper necked flange 4 is welded and fixed to the corner column steel pipe 1 after the prestressed hollow pile 2 is placed into the corner column steel pipe 1. The necked flange 4 is fixedly connected to the top and bottom ends of the prestressed hollow pile 2. Multiple grout outlet holes 44 are evenly opened on the upper necked flange 4. Multiple grouting holes 13 are opened at the bottom end of the corner column steel pipe 1. Grouting is performed from the bottom end of the corner column steel pipe 1 to the top to ensure complete filling.

[0027] Understandably, the bonding material 3 is injected into the gap between the corner column steel pipe 1 and the prestressed hollow pile 2 from the bottom end of the corner column steel pipe 1 using pressure grouting equipment. After being injected from the bottom end of the corner column steel pipe 1, the bonding material 3 flows from bottom to top, gradually filling the gap between the corner column steel pipe 1 and the prestressed hollow pile 2 until grout flows out of the grout outlet 44, ensuring complete filling without air bubbles, and further ensuring that the gap is completely filled. Thus, the combined structure of the precast prestressed hollow pile 2 and the corner column steel pipe 1 avoids the long curing process required for on-site concrete pouring, and the optimized grouting process and material selection together ensure the complete compaction of the bonding gap.

[0028] It is also understandable that the application of prestressed hollow piles 2 eliminates the redundant time of concrete curing, and the use of short-curing-time grouting material compresses the manufacturing cycle; at the same time, the synergistic effect of shear grooves 21 and stiffening ribs 11 or studs 12, as well as the flow path design of bottom-up grouting and the filling compensation mechanism of expansion agent, jointly ensure the density of the joint gaps and the integrity of the structure, thereby improving the construction efficiency and strength reliability of wind turbine tower corner columns.

[0029] like Figure 1 , Figure 4 , Figure 5 As shown, the neck flange 4 includes a flange 41, one side of which is fixedly connected to an inner ring plate 42 and an outer ring plate 43. The outer diameter of the inner ring plate 42 is equal to the inner diameter of the prestressed hollow pile 2, and the inner ring plate 42 is tightly fitted with the inner wall of the prestressed hollow pile 2. The diameter of the outer ring plate 43 is equal to the diameter of the corner column steel pipe 1, and the wall thickness of the outer ring plate 43 is consistent with the wall thickness of the corner column steel pipe 1. The outer ring plate 43 is welded and fixed to the corner column steel pipe 1.

[0030] It should be noted that the bottom end of the prestressed hollow pile 2 is embedded between the inner ring plate 42 and the outer ring plate 43 of the necked flange 4 at the bottom end of the corner column steel pipe 1, which allows the prestressed hollow pile 2 and the corner column steel pipe 1 to be placed coaxially. The necked flange 4 at the upper end is connected to the corner column steel pipe 1 after the prestressed hollow pile 2 is placed into the corner column steel pipe 1, thereby sealing the joint gap between the corner column steel pipe 1 and the prestressed hollow pile 2.

[0031] It is understood that in this embodiment, the neck flange 4 is integrally forged from carbon steel. The neck flange 4 is not only used to realize the connection and positioning function between the corner columns. The flange 41 serves as a basic connection platform. The inner ring plate 42 forms a gapless fit with the inner wall of the prestressed hollow pile 2, while the outer ring plate 43 is welded to the corner column steel pipe 1. This limits the relative position of the prestressed hollow pile 2 and the corner column steel pipe 1 during the corner column assembly process, thereby ensuring that the cementing material 3 can flow evenly along the joint gap and completely fill it during grouting. This effectively avoids positioning offset or filling defects caused by size mismatch. It can be seen that the neck flange 4 can also realize the connection and positioning function between the prestressed hollow pile 2 and the corner column steel pipe 1.

[0032] like Figure 1 , Figure 4 As shown, the grout outlet 44 is located on the flange 41 between the inner ring plate 42 and the outer ring plate 43, and is situated above the joint gap. Several flange bolt holes 45 are also evenly distributed on the flange 41 outside the outer ring plate 43. The grout outlet 44 is used to discharge excess grout and trapped air during the grouting process. It can be circular, elliptical, or rectangular. Its main function is to guide the grout to flow evenly upwards along the joint gap and completely expel air, avoiding filling defects. The flange bolt holes 45 are standardized holes for connecting necked flanges 4. They can be evenly spaced circular holes to ensure uniform stress distribution in the flange bolt holes 45 when the necked flanges 4 are connected.

[0033] In this embodiment, as Figure 1 , Figure 3 As shown, several horizontally placed threaded sleeves 22 are uniformly embedded in the circumferential direction of the inner wall of the top and bottom ends of the prestressed hollow pile 2. Locking bolt holes 46 corresponding to the threaded sleeves 22 are also opened on the inner ring plate 42 of the upper neck flange 4. After inserting the inner ring plate 42 of the upper neck flange 4 into the inner wall of the prestressed hollow pile 2, the locking bolt holes 46 are aligned with the threaded sleeves 22, and locking bolts 25 are used to connect the upper neck flange 4 and the prestressed hollow pile 2. After the cementing material 3 is poured and cured, the corner column is flipped over, and then the lower neck flange 4 and the prestressed hollow pile 2 are connected.

[0034] Understandably, the threaded sleeve 22 is a threaded connector pre-installed on the inner wall of the prestressed hollow pile 2. It can be implemented using a standard threaded sleeve or a custom-made sleeve, with the aim of providing a reliable bolt connection point. The locking bolt hole 46 on the inner ring plate 42 is a matching hole for the threaded sleeve 22. The neck flange 4 is welded and fixed to the corner column steel pipe 1 and bolted to the prestressed hollow pile 2, further ensuring the connection strength between the corner column steel pipe 1 and the prestressed hollow pile 2, and also guaranteeing the overall stability of the corner column during the grouting stage.

[0035] In some embodiments, when the inner diameter of the prestressed hollow pile 2 is inconvenient to operate, the threaded sleeve 22 is pre-embedded at the top and bottom of the prestressed hollow pile 2, and then locking bolt holes 46 are opened at the corresponding positions on the flange 41.

[0036] like Figure 2As shown, the corner column steel pipe 1 and the prestressed hollow pile 2 are aligned coaxially using an alignment member, which also enhances the torsional resistance of the corner column. The alignment member includes an alignment groove 14 on the inner wall of the corner column steel pipe 1, which is formed by two longitudinal stiffening ribs 11. It also includes an alignment plate 23 embedded in the outer wall of the prestressed hollow pile 2. The alignment plate 23 is a T-shaped plate, in which the horizontal plate is embedded in the prestressed hollow pile 2 and the vertical plate extends out of the prestressed hollow pile 2. The vertical plate can be inserted into the alignment groove 14.

[0037] In this embodiment, the alignment groove 14 formed by two longitudinal stiffening ribs 11 can serve as a linear guide channel, providing path constraints for the insertion of the prestressed hollow pile 2. The radial length of the stiffening ribs 11 is less than the radial length of the joint gap, and the radial length of the vertical plate on the outer wall of the prestressed hollow pile 2 is less than the radial length of the joint gap. Opposing limiting plates 24 are welded on both sides of the vertical plate. The limiting plates 24 abut against the stiffening ribs 11, guiding the prestressed hollow pile 2 to move along a predetermined path, avoiding radial offset during the insertion process, ensuring that the corner column steel pipe 1 and the prestressed hollow pile 2 are coaxially aligned, ensuring coaxiality, and strengthening the torsional resistance of the corner column.

[0038] In this embodiment, during the prefabrication of the prestressed hollow pile 2, a shear groove 21 is pre-set on its outer wall surface. The depth of the shear groove 21 is 1-3 cm. This depth range avoids both insufficient interlocking force due to being too shallow and failing to effectively resist shear stress, and excessive depth that weakens the structural strength of the prestressed hollow pile 2. The purpose is to achieve an optimized balance between interfacial bonding force and structural integrity. The spacing of the shear grooves 21 is 10-20 cm, which refers to the center distance between adjacent shear grooves 21. The purpose is to ensure uniform circumferential force, avoid weak bonding points or stress concentration in local areas, enhance the bonding performance with the adhesive material, and enhance the shear resistance.

[0039] By precisely defining the geometric parameters of the shear groove 21 during the prefabrication stage, a stable mechanical interlocking interface is formed on the outer wall surface of the prestressed hollow pile 2. During the filling process of the bonding material 3, this interface ensures the balance between the interlocking force and the pile strength, and guarantees the uniformity of circumferential stress. The synergistic effect of the two allows the bonding material 3 to be fully embedded and form a continuous and dense filling layer, thereby effectively solving the problems of insufficient bonding interface strength and unstable shear performance.

[0040] like Figure 6As shown, the connection between the prestressed hollow pile 2 and the corner column steel pipe 1 requires the use of the production frame 5. The production frame 5 includes four frame columns 51. The upper, middle and lower ends of the frame columns 51 are all fixedly connected to the crossbeams 52. Multiple (three in this embodiment) hoop rings 53 are set in the center of the production frame 5. The diameter of the hoop rings 53 is equal to the outer diameter of the neck flange 4. The hoop rings 53 are fixedly connected to the frame columns 51 by the inclined beams 54. The corner column steel pipe 1 is vertically passed through the multiple hoop rings 53. Then the prestressed hollow pile 2 is placed in the corner column steel pipe 1 to achieve the support and positioning of the processing.

[0041] Understandably, the production stand 5 is a specialized tooling device used to support and position the corner column steel pipe 1. It can be implemented using a steel structure frame to provide support and prevent the corner column from overturning. The frame column 51 refers to the column structure that constitutes the main support of the production stand 5. It can be implemented using H-beams or steel-concrete composite columns to bear the overall load and maintain structural stability. The hoop 53 refers to the annular restraint component surrounding the corner column steel pipe 1. It can be implemented using an integral cast steel ring to prevent the corner column from overturning and maintain the verticality of the corner column steel pipe 1. The inclined beam 54 refers to the supporting component that connects the hoop 53 and the frame column 51. It can be welded from angle steel or channel steel to evenly transfer the force of the hoop 53 to the frame column 51 and prevent local deformation.

[0042] In this embodiment, the production stand 5 can be made of Q345B steel.

[0043] like Figure 7 As shown, the outer wall of the corner column steel pipe 1 is fixedly connected to the connecting node 6, which is used to connect the diagonal column or horizontal bar of the wind turbine tower. After the adhesive material 3 is poured, the corner column steel pipe 1 is lifted out of the production frame 5 and then fixedly connected to the connecting node 6 (e.g., by welding).

[0044] Example 2 This embodiment discloses a construction method for a composite prestressed steel-concrete composite wind turbine tower corner column, which applies a composite prestressed steel-concrete composite wind turbine tower corner column disclosed in Embodiment 1. The specific steps are as follows: Prestressed hollow piles 2 are fabricated in the prefabrication yard, and corner steel pipes 1 and neck flanges 4 are fabricated in the processing yard. Neck flanges 4 are welded to the bottom end of corner steel pipes 1. Place the corner column steel pipe 1 into the hoop 53 of the production stand 5, then hoist the prestressed hollow pile 2 into the corner column steel pipe 1, so that the alignment plate 23 is inserted into the alignment groove 14. Then install the upper neck flange 4 on the top of the corner column steel pipe 1 and the prestressed hollow pile 2. Use locking bolts to connect the inner ring plate 42 of the neck flange 4 to the prestressed hollow pile 2. Then weld the outer ring plate 43 to the corner column steel pipe 1 for fixation. Finally, cementing material 3 with added expansion agent is injected from the grouting hole 13 at the bottom of the corner column steel pipe 1 until grout comes out of the grout outlet hole 44; after curing, the production of the composite prestressed steel pipe concrete wind turbine tower corner column is realized.

[0045] It should be noted that in this embodiment, the prestressed hollow piles 2 and the corner column steel pipes 1 are nested together in a nested manner, and the bottom grouting and top grouting process is used in conjunction with high-strength grouting material with added expansion agent. This effectively avoids the long curing process of on-site concrete pouring, while ensuring the complete filling of the joint gaps, thus achieving the effect of significantly shortening the preparation cycle and eliminating the phenomenon of incomplete filling.

[0046] Specifically, the application of precast prestressed hollow piles eliminates the waiting time for on-site concrete pouring, while the bottom-up grouting process uses gravity to drive the grout to rise naturally, effectively eliminating air and voids. Combined with the characteristics of high-strength grout with added expansion agent, the material expands moderately during the hardening process, filling the entire bond void. This not only significantly shortens the curing time but also completely solves the hidden danger of incomplete filling.

[0047] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A composite prestressed steel-concrete composite wind turbine tower corner column, characterized in that, It includes a corner steel pipe, a pre-stressed hollow pile is installed inside the corner steel pipe, and a bonding gap is formed between the corner steel pipe and the pre-stressed hollow pile, and the bonding gap is filled with a bonding material with an expansion agent added. The inner wall of the corner column steel pipe is fixedly connected with stiffening ribs or studs, and the outer wall of the prestressed hollow pile has several shear grooves preset. The upper and lower ends of the corner column are fixedly connected with necked flanges. The lower necked flange is welded and fixed to the corner column steel pipe, and the upper necked flange is welded and fixed to the corner column steel pipe after the prestressed hollow pile is placed into the corner column steel pipe. The necked flange is fixedly connected to the top and bottom of the prestressed hollow pile. Multiple grout outlet holes are evenly opened on the upper necked flange, and multiple grout injection holes are opened at the bottom of the corner column steel pipe. Grouting is performed from bottom to top from the bottom of the corner column steel pipe.

2. The composite prestressed steel-concrete composite wind turbine tower corner column as described in claim 1, characterized in that, The necked flange includes a flange plate, on one side of which an inner ring plate and an outer ring plate are fixedly connected. The outer diameter of the inner ring plate is equal to the inner diameter of the prestressed hollow pile, the diameter of the outer ring plate is equal to the diameter of the corner column steel pipe, and the wall thickness of the outer ring plate is equal to the wall thickness of the corner column steel pipe.

3. A composite prestressed steel-concrete composite wind turbine tower corner column as described in claim 2, characterized in that, The slurry outlet is located on the flange between the inner ring plate and the outer ring plate, and the slurry outlet is located above the joint gap; a number of flange bolt holes are also evenly provided on the flange outside the outer ring plate.

4. A composite prestressed steel-concrete composite wind turbine tower corner column as described in claim 2, characterized in that, Several horizontally placed threaded sleeves are evenly embedded in the inner circumferential direction of the top and bottom of the prestressed hollow pile. Locking bolt holes corresponding to the threaded sleeves are also opened on the inner ring plate, and the threaded sleeves are threadedly connected to the locking bolts.

5. A composite prestressed steel-concrete composite wind turbine tower corner column as described in claim 1, characterized in that, The corner column steel pipe and the prestressed hollow pile are reinforced with an alignment member for coaxial alignment. The alignment member includes an alignment groove on the inner wall of the corner column steel pipe, which is surrounded by two longitudinal stiffening ribs. It also includes an alignment plate embedded in the outer wall of the prestressed hollow pile. The alignment plate is a T-shaped plate, with its horizontal plate embedded in the prestressed hollow pile and its vertical plate extending out of the prestressed hollow pile and inserted into the alignment groove.

6. A composite prestressed steel-concrete composite wind turbine tower corner column as described in claim 5, characterized in that, The radial length of the stiffening rib is less than the radial length of the connecting gap, and the radial length of the vertical plate on the outer wall of the prestressed hollow pile is less than the radial length of the connecting gap. Opposite limiting plates are welded on both sides of the vertical plate, and the limiting plates abut against the stiffening rib.

7. A composite prestressed steel-concrete composite wind turbine tower corner column as described in claim 1, characterized in that, The depth of the shear groove is 1-3 cm, and the spacing between the shear grooves is 10-20 cm.

8. A composite prestressed steel-concrete composite wind turbine tower corner column as described in claim 1, characterized in that, The connection between the prestressed hollow piles and the corner steel pipes requires the use of a production frame. The production frame includes four frame columns, with crossbeams fixedly connected to the upper, middle, and lower ends of the frame columns. Multiple hoop rings are set at the center of the production frame, with the diameter of the hoop rings equal to the outer diameter of the necked flange. The hoop rings are fixedly connected to the frame columns by inclined beams.

9. A composite prestressed steel-concrete composite wind turbine tower corner column as described in claim 1, characterized in that, The outer wall of the corner steel pipe is fixedly connected to the connection node of the wind turbine tower inclined column or crossbar.

10. A construction method for a composite prestressed steel-concrete composite wind turbine tower corner column as described in any one of claims 1-9, characterized in that, The specific steps are as follows: The prestressed hollow piles are processed in the prefabrication yard, and the corner column steel pipes and the necked flanges are processed in the processing yard. The necked flanges are welded to the bottom end of the corner column steel pipes. Place the corner column steel pipe into the hoop of the production stand, then hoist the prestressed hollow pile into the corner column steel pipe, so that the alignment plate is inserted into the alignment groove. Then install the upper neck flange on the top of the corner column steel pipe and the prestressed hollow pile. Use the locking bolt to connect the inner ring plate to the prestressed hollow pile. Then weld the outer ring plate to the corner column steel pipe for fixation. Finally, a cementing material with added expansion agent is injected into the grouting hole at the bottom of the corner column steel pipe until grout comes out of the grout outlet hole; after curing, the corner column is produced.

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