A prestressed foundation with replaceable anchor bolts

Abstract

The embodiment of the present invention discloses a prestressed foundation with replaceable anchor bolts, including a concrete foundation and a prestressed anchor bolt assembly embedded in the concrete foundation; the prestressed anchor bolt assembly includes an upper anchor plate embedded in the top of the concrete foundation, a lower anchor plate embedded in the bottom of the concrete, and a plurality of prestressed anchor bolts, the upper end of the prestressed anchor bolt vertically penetrates the first through hole of the upper anchor plate and is connected to the first nut, the lower end of the prestressed anchor bolt vertically penetrates the second through hole of the lower anchor plate and is connected to the second nut, the part of the prestressed anchor bolt located between the upper anchor plate and the lower anchor plate is provided with an outer sleeve, the upper and lower ends of the outer sleeve are respectively sealed to connect the upper anchor plate and the lower anchor plate, and a sealing sleeve is provided at the bottom of the prestressed anchor bolt. The present invention arranges an outer sleeve in the middle of the anchor bolt and a sealing sleeve at the bottom of the anchor bolt, completely isolates the prestressed anchor bolt from the concrete foundation, realizes the disassembly of the prestressed anchor bolt, and achieves the purpose of the anchor bolt being replaceable and recyclable, and the replacement construction is simple, saving a lot of maintenance costs.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of wind turbine foundations, and in particular to a prestressed foundation with replaceable anchor bolts. Background Art

[0002] With the continuous maturity of wind power technology and the substantial increase in the capacity of single units, the safe operation of wind turbines places higher demands on the reliability of tower foundations. Currently, anchor foundations consisting of prestressed anchor bolt assemblies and concrete foundations are widely used in various types of wind turbines in inland wind farms.

[0003] Among them, the prestressed anchor bolt assembly is composed of a number of anchor bolts and an anchor cage ring composed of upper and lower anchor plates. The anchor bolt foundation is cast in one go, fixed by upper and lower anchor plates, and connected to the flange of the lower section of the tower. During the operation of the wind turbine, the tower is affected by the wind due to the wind turbine blades, and a transverse bending moment is also formed on the tower. This bending moment is transmitted to the anchor bolt, forming an axial tension on the anchor bolt. When the tension exceeds the maximum tensile strength of the anchor bolt or the anchor bolt is severely corroded, the anchor bolt is prone to break. If the broken anchor bolt is not repaired or replaced in time, the remaining anchor bolts will be more likely to break in turn, which will bring great hidden dangers to the safe operation of the wind turbine. In addition, the design life of reinforced concrete is 50 years, and the fatigue life of the wind turbine and anchor cage ring is 20 years. After the wind turbine and anchor cage ring reach their fatigue life, if the anchor bolt can be replaced, the original reinforced concrete foundation can be reused to achieve energy conservation and emission reduction, and waste utilization.

[0004] However, since the prestressed anchor bolts are embedded in the concrete foundation, on-site repair is difficult to achieve. The concrete around the prestressed anchor bolts needs to be destroyed, and there is also the problem of the anchor bolts being detached from the upper and lower anchor plates. This method is time-consuming, labor-intensive, and costly, and it is impossible to reuse the concrete foundation. Therefore, a low-cost technology that is easy to remove broken anchor bolts is needed. Summary of the invention

[0005] To this end, an embodiment of the present invention provides a prestressed foundation with replaceable anchor bolts, and provides a technology for replacing prestressed anchor bolts without damaging the concrete foundation.

[0006] In order to achieve the above purpose, the embodiment of the present invention provides the following technical solutions:

[0007] A prestressed foundation with replaceable anchor bolts, comprising a concrete foundation and a prestressed anchor bolt assembly embedded in the concrete foundation; the prestressed anchor bolt assembly comprises an upper anchor plate embedded in the top of the concrete foundation, a lower anchor plate embedded in the bottom of the concrete and a plurality of prestressed anchor bolts, the upper end of the prestressed anchor bolt vertically penetrates the first through hole of the upper anchor plate and is connected to a first nut, the lower end of the prestressed anchor bolt vertically penetrates the second through hole of the lower anchor plate and is connected to a second nut, the portion of the prestressed anchor bolt located between the upper anchor plate and the lower anchor plate is provided with an outer sleeve, the upper and lower ends of the outer sleeve are respectively sealed and connected to the upper anchor plate and the lower anchor plate, and a sealing sleeve is provided at the bottom of the prestressed anchor bolt.

[0008] Furthermore, the second nut and the sealing sleeve are an integral structure.

[0009] Furthermore, the sealing sleeve is sleeved on the outside of the second nut.

[0010] Furthermore, the upper and lower ends of the outer sleeve are sealed and connected to the upper anchor plate and the lower anchor plate through heat shrink tubes.

[0011] Furthermore, a third nut located on the upper part of the lower anchor plate is provided at the bottom of the prestressed anchor bolt.

[0012] Furthermore, a connector penetrating the lower anchor plate is provided between the second nut and the prestressed anchor bolt, the connector is sleeved on the prestressed anchor bolt, an internal thread matching the prestressed anchor bolt is provided on the connector body, an external thread matching the second nut is provided on the connector body, and a first locking structure extending outward is provided on the top of the connector, and a width of the first locking structure is greater than the aperture of the second through hole in the lower anchor plate.

[0013] Furthermore, the sealing sleeve and the connecting body are an integral structure.

[0014] Furthermore, a disassembly thread is provided on the inner side or the outer side of the first locking structure, the disassembly thread has an opposite rotation direction to the external thread, and the thread radius of the disassembly thread is larger than the thread radius of the internal thread; a shrinkage hole structure is provided in the first through hole of the upper anchor plate, and a second locking structure wider than the aperture of the first through hole is provided on the upper part of the shrinkage hole structure, and the lower part of the shrinkage hole structure is inserted into the first through hole, and a third through hole for the prestressed anchor bolt to pass through is provided on the shrinkage hole structure.

[0015] Furthermore, a protruding structure cooperating with the outer sleeve is provided at the bottom of the shrinkage hole structure.

[0016] Furthermore, the bottom thread of the outer sleeve is connected to the disassembly thread.

[0017] The embodiments of the present invention have the following advantages:

[0018] The prestressed foundation with replaceable anchor bolts described in the embodiment of the present invention completely isolates the prestressed anchor bolt from the concrete foundation by providing an outer sleeve in the middle of the anchor bolt and a sealing sleeve at the bottom of the anchor bolt. When the prestressed anchor bolt needs to be replaced, the broken upper anchor bolt is firstly taken out directly from the outside of the concrete foundation, and then the broken lower anchor bolt is rotated by inserting a tool into the concrete foundation to separate the anchor bolt from the lower anchor plate, thereby realizing the disassembly of the prestressed anchor bolt and achieving the purpose of replaceable and recyclable anchor bolts. The replacement construction is simple, and a large amount of maintenance costs are saved at the same time, thereby improving the economic value of the foundation.

[0019] The prestressed foundation with replaceable anchor bolts described in the embodiment of the present invention arranges a connecting body between the lower anchor plate and the prestressed anchor bolt. When the prestressed anchor bolt is replaced, the connecting body can be taken out to check whether the thread used to fix the prestressed anchor bolt is damaged, thereby ensuring the effectiveness of the connection between the new prestressed anchor bolt and the lower anchor plate, eliminating the hidden risks of replacing the prestressed anchor bolt, and thus avoiding greater risks. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the implementation methods of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the implementation methods or the description of the prior art. Obviously, the drawings in the following description are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0021] The structures, proportions, sizes, etc. illustrated in this specification are only used to match the contents disclosed in the specification so as to facilitate understanding and reading by persons familiar with the technology. They are not used to limit the conditions under which the present invention can be implemented, and therefore have no substantial technical significance. Any structural modification, change in proportion or adjustment of size shall still fall within the scope of the technical contents disclosed in the present invention without affecting the effects and purposes that can be achieved by the present invention.

[0022] Figure 1 A basic structural diagram of a prestressed foundation with replaceable anchor bolts provided in any one of Embodiments 1 to 4 of the present invention;

[0023] Figure 2 A partial cross-sectional view of a lower anchor plate of another prestressed foundation with replaceable anchor bolts provided in Example 1 of the present invention;

[0024] Figure 3 A partial cross-sectional view of a lower anchor plate of a prestressed foundation with replaceable anchor bolts provided in Example 2 of the present invention;

[0025] Figure 4 A partial cross-sectional view of a lower anchor plate of another prestressed foundation with replaceable anchor bolts provided in Example 2 of the present invention;

[0026] Figure 5 A partial cross-sectional view of a lower anchor plate of a prestressed foundation with replaceable anchor bolts provided in Example 3 of the present invention;

[0027] Figure 6 A partial cross-sectional view of a lower anchor plate of a prestressed foundation with replaceable anchor bolts provided in Example 4 of the present invention.

[0028] In the figure:

[0029] 1. Concrete foundation; 2. Upper anchor plate; 3. Lower anchor plate; 4. Prestressed anchor bolt; 5. First nut; 6. First through hole; 7. Second nut; 8. Second through hole; 9. Outer sleeve; 10. Third nut; 11. Connector; 12. Internal thread; 13. External thread; 14. First clamping structure; 15. Sealing sleeve; 16. Disassembly thread; 17. Shrinkage hole structure; 18. Second clamping structure; 19. Third through hole. DETAILED DESCRIPTION

[0030] The following is a description of the implementation of the present invention by specific embodiments. People familiar with the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] Example 1

[0032] like Figure 1 As shown, a prestressed foundation with replaceable anchor bolts includes a concrete foundation 1 formed by pouring reinforced concrete, and a prestressed anchor bolt 4 component embedded in the concrete foundation 1. The concrete foundation 1 can be a hollow structure, and a manhole can be provided on the top of the hollow structure for workers to enter the concrete foundation 1 to perform relevant maintenance work. In this embodiment, the prestressed anchor bolt 4 component is an annular structure, and the inner and outer sides of the prestressed anchor bolt 4 component are respectively provided with an inner steel formwork and an outer steel formwork, which are used to increase the stability of the concrete around the prestressed anchor bolt 4 component.

[0033] The prestressed anchor bolt 4 assembly includes an upper anchor plate 2 embedded in the top of the concrete foundation 1, a lower anchor plate 3 embedded in the bottom of the concrete, and a plurality of prestressed anchor bolts 4. The upper end of the prestressed anchor bolt 4 vertically penetrates the first through hole 6 of the upper anchor plate 2 and is connected to the first nut 5. The lower end of the prestressed anchor bolt 4 vertically penetrates the second through hole 8 of the lower anchor plate 3 and is connected to the second nut 7. The upper and lower ends of the prestressed anchor bolt 4 are fixed by the first nut 5 and the second nut 7 respectively.

[0034] The part of the prestressed anchor bolt 4 between the upper anchor plate 2 and the lower anchor plate 3 is provided with an outer sleeve 9, which is a PVC pipe, a pve pipe, a steel pipe, etc., and its function is to isolate the prestressed anchor bolt 4 from the concrete foundation 1, prevent the prestressed anchor bolt 4 from being corroded by moisture, and make the prestressed anchor bolt 4 separate from the concrete foundation 1, so as to facilitate its replacement. The upper and lower ends of the outer sleeve 9 are respectively sealed to connect the upper anchor plate 2 and the lower anchor plate 3. If both ends of the outer sleeve 9 are sealed with a heat shrink tube, the heat shrink structure of the heat shrink tube cannot be controlled, and it is easy to squeeze the prestressed anchor bolt 4, making it impossible to replace; or one end of the outer sleeve 9 is welded to the upper anchor plate 2 or the lower anchor plate 3, and the other end is inserted into the lower anchor plate 3 or the upper anchor plate 2, then this structure adds a welding process during construction, the overall construction cost is high, and the welding process requirements are high, and the accuracy is difficult to ensure; or one end of the outer sleeve 9 is threadedly connected to the upper anchor plate 2 or the lower anchor plate 3, and the other end is inserted into the lower anchor plate 3 or the upper anchor plate 2. This structure is fast to construct and has low construction cost.

[0035] The bottom of the prestressed anchor bolt 4 is provided with a sealing sleeve 15, which is sleeved on the outside of the second nut 7 and fixedly connected to the lower anchor plate 3. It is used to isolate the prestressed anchor bolt 4 protruding from the bottom of the lower anchor plate 3 from the concrete foundation 1, prevent moisture from corroding the prestressed anchor bolt 4 and the second nut 7, ensure the smoothness of the connection between the two, and when the prestressed anchor bolt 4 is replaced, the two will not stick together due to rust, and also prevent the problem that the concrete foundation 1 fixes the prestressed anchor bolt 4 and makes it impossible to replace it.

[0036] Or, to reduce costs, e.g. Figure 2 As shown, the second nut 7 and the sealing sleeve 15 are combined into an integral structure, and there is no need to weld the sealing sleeve 15 to the lower anchor plate 3 or the second nut 7 during construction, which saves construction technology. Moreover, the two are an integral structure with no gap between them, which can increase the sealing performance.

[0037] Example 2

[0038] like Figure 3 As shown, the bottom of the prestressed anchor bolt 4 is provided with a third nut 10 located on the upper part of the lower anchor plate 3. When the anchor bolt breaks, the prestressed anchor bolt 4 that is broken at the bottom will break away from the lower anchor plate 3 downward due to the reaction force, so that the connection between the prestressed anchor bolt 4 and the lower anchor plate 3 fails, which seriously damages the support balance of the adjacent prestressed anchor bolts 4 at the broken part, and is also easy to damage the thread of the second nut 7, and the prestressed anchor bolt 4 cannot be connected again due to thread deformation. The third nut 10 is set on the top of the lower anchor plate 3, so that the bottom of the prestressed anchor bolt 4 is fixedly connected to the lower anchor plate 3. When the anchor bolt breaks, the prestressed anchor bolt 4 is locked on the lower anchor plate 3 by the second nut 7 and the third nut 10. The two nuts provide a certain support force for the prestressed anchor bolt 4, which effectively reduces the risk of failure of the connection between the prestressed anchor bolt 4 and the lower anchor plate 3 after the prestressed anchor bolt 4 breaks.

[0039] Or, if Figure 4 As shown, a connector 11 penetrating the lower anchor plate 3 is provided between the second nut 7 and the prestressed anchor bolt 4, and the connector 11 is sleeved on the prestressed anchor bolt 4. An internal thread 12 matching the prestressed anchor bolt 4 is provided inside the connector 11, and an external thread 13 matching the second nut 7 is provided outside the connector 11, and the internal thread 12 and the external thread 13 have the same rotation direction. A first locking structure 14 extending outward is provided on the top of the connector 11, and the width of the first locking structure 14 is greater than the aperture of the second through hole 8 on the lower anchor plate 3, so that after the connector 11 is inserted from the upper part of the lower anchor plate 3, the first locking structure 14 is stuck on the top of the lower anchor plate 3, so that the connector 11 cannot be separated from the lower anchor plate 3 after penetrating the lower anchor plate 3, thereby ensuring that the connection between the two is effective. During specific use, the connector 11 is threadedly connected to the bottom of the prestressed anchor 4, and then one end of the connector 11 of the prestressed anchor 4 is inserted into the lower anchor plate 3, and the second nut 7 is threadedly connected to the connector 11, thereby achieving a fixed connection between the prestressed anchor 4 and the lower anchor plate 3, thereby ensuring an effective connection between the prestressed anchor 4 and the lower anchor plate 3.

[0040] Alternatively, the sealing sleeve 15 is arranged on the connecting body 11, and the two can be an integral structure or a separate structure. The integral structure is preferred, which has the advantages of reducing costs and facilitating processing, and there is no need to add welding technology for the sealing sleeve 15 during construction.

[0041] Example 3

[0042] like Figure 5 As shown, a disassembly thread 16 is provided on the inner side or the outer side of the first locking structure 14 . The rotation direction of the disassembly thread 16 is opposite to that of the external thread 13 . The thread radius of the disassembly thread 16 is greater than the thread radius of the internal thread 12 .

[0043] A shrinkage hole structure 17 is provided in the first through hole 6 of the upper anchor plate 2, and a second locking structure 18 is provided on the upper part of the shrinkage hole structure 17, which is wider than the aperture of the first through hole 6. The lower part of the shrinkage hole structure 17 is inserted into the first through hole 6, and a third through hole 19 is provided on the shrinkage hole structure 17 for the prestressed anchor bolt 4 to pass through. When in use, the shrinkage hole structure 17 is installed on the upper anchor plate 2, and the shrinkage hole structure 17 is inserted into the upper anchor plate 2 from the upper part. The second locking structure 18 will lock the shrinkage hole structure 17 to prevent the shrinkage hole structure 17 from passing through the upper anchor plate 2, and then the prestressed anchor bolt 4 passes through the third through hole 19 of the shrinkage hole structure 17. When the anchor bolt is broken, remove the first nut 5, remove the shrinkage structure 17 and the upper broken structure of the prestressed anchor bolt 4, use the disassembly device to take out the lower broken structure, and then use a special tool to reach deep into the lower anchor plate 3 and connect with the disassembly thread 16 on the connector 11. Since the disassembly thread 16 is in the opposite direction of the external thread 13, the reverse rotation of the external thread 13 can tighten the thread between the special tool and the connector 11 and untie the threaded connection between the connector 11 and the second nut 7, thereby achieving the effect of disassembling the connector 11. Then the thread condition of the connector 11 can be checked. If the thread is damaged, the connector 11 can be replaced.

[0044] The bottom of the shrinkage structure 17 is provided with a protrusion structure that cooperates with the outer sleeve 9. The width of the shrinkage structure 17 is greater than the diameter of the outer sleeve 9, which is convenient for replacing the outer sleeve 9. The protrusion structure can block the outer sleeve 9 for connection and sealing between the two.

[0045] Example 4

[0046] like Figure 6 As shown, the bottom thread of the outer sleeve 9 is connected to the disassembly thread 16, and the outer side of the outer sleeve 9 is coated with a concrete release agent. When the prestressed anchor 4 is broken, after taking out the broken upper prestressed anchor 4, use a tool to take out the broken lower prestressed anchor 4, such as using a self-tapping thread drill to drill into the broken section, and the drill drives the broken anchor to rotate in the opposite direction, and separate from the connector 11, so as to remove the broken anchor. Then, the outer sleeve 9 is rotated to make the outer sleeve 9 drive the connector 11 to rotate. Since the disassembly thread 16 and the thread of the second nut 7 have opposite rotation directions, when the outer sleeve 9 is rotated, the outer sleeve 9 can separate the connector 11 from the second nut 7 without separating from the connector 11, thereby realizing the replacement of the connector 11. No other equipment is required to go deep into the bottom. Only the outer sleeve 9 needs to be rotated to replace the connector 11 or check the thread condition of the connector 11.

[0047] Although the present invention has been described in detail above by general description and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements can be made to the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all belong to the scope of protection claimed by the present invention.

Claims

1. A prestressed foundation with replaceable anchor bolts, characterized in that: It includes a concrete foundation and a prestressed anchor bolt assembly embedded in the concrete foundation; The prestressed anchor bolt assembly comprises an upper anchor plate pre-buried in the top of the concrete foundation, a lower anchor plate pre-buried in the bottom of the concrete, and a plurality of prestressed anchor bolts, the upper end of the prestressed anchor bolt vertically passes through the first through hole of the upper anchor plate and is connected to the first nut, the lower end of the prestressed anchor bolt vertically passes through the second through hole of the lower anchor plate and is connected to the second nut, the portion of the prestressed anchor bolt located between the upper anchor plate and the lower anchor plate is provided with an outer sleeve, the upper and lower ends of the outer sleeve are respectively sealed and connected to the upper anchor plate and the lower anchor plate, and the bottom of the prestressed anchor bolt is provided with a sealing sleeve; A connector penetrating the lower anchor plate is provided between the second nut and the prestressed anchor bolt, the connector is sleeved on the prestressed anchor bolt, an internal thread matching the prestressed anchor bolt is provided in the connector body, an external thread matching the second nut is provided outside the connector body, a first clamping structure extending outward is provided on the top of the connector body, and the width of the first clamping structure is greater than the aperture of the second through hole on the lower anchor plate; A disassembly thread is provided on the inner side or the outer side of the first locking structure, the rotation direction of the disassembly thread is opposite to that of the external thread, and the thread radius of the disassembly thread is greater than the thread radius of the internal thread; A shrinkage hole structure is provided in the first through hole of the upper anchor plate, a second locking structure wider than the first through hole is provided on the upper portion of the shrinkage hole structure, a lower portion of the shrinkage hole structure is inserted into the first through hole, and a third through hole for the prestressed anchor bolt to penetrate is provided on the shrinkage hole structure; The bottom thread of the outer sleeve is connected to the disassembly thread, and the outer side of the outer sleeve is coated with a concrete release agent.

2. The prestressed foundation with replaceable anchor bolts according to claim 1, characterized in that: The second nut and the sealing sleeve are an integral structure.

3. The prestressed foundation with replaceable anchor bolts according to claim 1, characterized in that: The sealing sleeve is sleeved on the outer side of the second nut.

4. The prestressed foundation with replaceable anchor bolts according to claim 1, characterized in that: The upper and lower ends of the outer sleeve are sealed and connected to the upper anchor plate and the lower anchor plate through heat shrink tubes.

5. The prestressed foundation with replaceable anchor bolts according to claim 1, characterized in that: The bottom of the prestressed anchor bolt is provided with a third nut located on the upper part of the lower anchor plate.

6. The prestressed foundation with replaceable anchor bolts according to claim 1, characterized in that: The sealing sleeve and the connecting body are an integral structure.

7. The prestressed foundation with replaceable anchor bolts according to claim 1, characterized in that: The bottom of the shrinkage hole structure is provided with a protrusion structure which cooperates with the outer sleeve.

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