Pressure type PSB prestressed anchor rod

Abstract

This invention belongs to the field of anti-buoyancy anchor technology and discloses a pressure-type PSB prestressed anchor to solve the problem of poor waterproofing effect of finely rolled threaded steel bars along their entire length. The anchor of this invention includes finely rolled threaded steel bars, with a bearing body at the bottom of the bar and the upper end extending upwards into the foundation or base slab. A sleeve is fitted around the bar, with both the upper and lower ends extending out of the sleeve. The upper end face of the sleeve is flush with the upper end face of the anchor hole. An upper waterproofing structure is provided at the upper end of the bar. This invention utilizes an expansion sealing ring and an elastic rubber nut to achieve a double seal inside the sleeve, allowing the expansion sealing ring to function as a sealant; and works in conjunction with the external heat-shrinkable tube and waterproof tape to improve the sealing effect.

Description

Technical Field

[0001] This invention belongs to the field of anti-buoyancy anchor technology, specifically relating to a pressure-type PSB prestressed anchor. Background Technology

[0002] Anti-buoyancy anchors, as an anti-buoyancy measure for building structures, are connected to the foundation slab of the building to resist the buoyancy force generated by groundwater on the underground structure of the building, and to prevent the underground structure from being damaged by the buoyancy force of groundwater.

[0003] For pressure-type anti-buoyancy anchors, in some geological conditions, it is necessary to perform anti-corrosion treatment on the entire length of the precision-rolled threaded steel bars (commonly known as PSB). Currently, the method for waterproofing the entire length of PSB is as follows: a sleeve is installed around the PSB, and the sleeve is filled with anti-corrosion grease. The anti-corrosion grease is used to waterproof the PSB. Although an expansion seal ring and waterproof tape are used to seal the end of the sleeve with the PSB, in actual use, because the waterproof tape itself provides some waterproofing, the expansion seal ring cannot expand upon contact with water. This leads to some of the anti-corrosion grease slowly seeping out from the expansion seal ring, especially at the bottom of the PSB. Only when the waterproof tape is applied and prestressing is applied... Groundwater can only come into contact with the expansion seal ring after it has been damaged by force or prolonged use. Only then can the expansion seal ring play a sealing role. However, the damage to the waterproof tape itself has a certain degree of randomness (accidental collision damage) and time-limited effect (i.e., the waterproof tape naturally ages and fails). If the waterproof tape naturally ages and loses its waterproof effect, the service life of the expansion seal ring will also be consumed for a long time. This will reduce the expansion seal ring's ability to expand when it comes into contact with water, and it will be unable to play its role in expanding and sealing. As a result, groundwater will directly enter the casing and corrode the PSB precision-rolled threaded steel bars, thus affecting the durability and service life of the anti-buoyancy anchor.

[0004] In other words, although the existing technology uses waterproof tape and expansion seal ring to waterproof the end of the casing, on the one hand, the waterproof functions of the waterproof tape and expansion seal ring are basically independent of each other, resulting in poor waterproof effect; on the other hand, the expansion seal ring cannot fully exert its waterproof effect, which leads to groundwater entering the casing and corroding the fine-rolled threaded steel bars, ultimately affecting the durability and service life of the anti-buoyancy anchor. Summary of the Invention

[0005] To address the problem of poor waterproofing effect of finely rolled threaded steel bars along their entire length, this invention provides a pressure-type PSB prestressed anchor rod.

[0006] To solve the technical problem, the technical solution adopted by this invention is as follows: A pressure-type PSB prestressed anchor bolt includes a finely rolled threaded steel bar. The lower bottom of the finely rolled threaded steel bar is provided with a bearing body that extends into the anchor hole. The upper end of the finely rolled threaded steel bar extends upward into the foundation or base plate. A sleeve filled with anti-corrosion grease is fitted around the finely rolled threaded steel bar. Both the upper and lower ends of the finely rolled threaded steel bar extend out of the sleeve. The characteristic feature is that the upper end face of the sleeve is flush with the upper end face of the anchor hole, and the upper end of the finely rolled threaded steel bar is provided with an upper waterproof structure.

[0007] In some embodiments, the upper waterproof structure includes a heat shrinkable tube, the lower end of which is sleeved around the outer periphery of the sleeve and connected to the sleeve by wrapping with waterproof tape. The upper end of the heat shrinkable tube is sleeved around the outer periphery of the fine-rolled threaded steel bar and extends out through an anchor hole into the foundation or base plate. The upper end of the heat shrinkable tube and the fine-rolled threaded steel bar are connected by wrapping with waterproof tape. The upper waterproof structure also includes an expansion water-stop ring and an elastic rubber nut installed on the upper section of the fine-rolled threaded steel bar and adapted to the sleeve. The elastic rubber nut is located below the expansion water-stop ring and contacts the expansion water-stop ring. The upper end face of the expansion water-stop ring is aligned with the upper end face of the anchor hole.

[0008] In some embodiments, the heat shrink tube located around the sleeve is heated and then bonded to the sleeve before being wrapped with waterproof tape.

[0009] In some embodiments, the heat shrink tube corresponding to the upper end position of the anchor hole, after being heated, plays a limiting role in the expansion sealing ring.

[0010] In some embodiments, the heat shrink tube extending out of the anchor hole is heated after prestressing is applied to the fine-rolled threaded steel bar to fit it; the upper end of the heat shrink tube is then wrapped and connected to the fine-rolled threaded steel bar with waterproof tape after prestressing is applied to it.

[0011] In some embodiments, the finely rolled threaded steel bar is equipped with a cylindrical prestressed cylinder, and the circumferential arm of the prestressed cylinder has multiple strip-shaped operating windows for waterproof tape to pass through.

[0012] In some embodiments, after the finely rolled threaded steel bar is prestressed, the prestressing cylinder is cast together in the foundation or base slab.

[0013] In a preferred embodiment of the present invention, a pad is provided at the bottom of the prestressed cylinder, and a through hole is provided in the middle of the pad for the heat shrink tube and the fine-rolled threaded steel bar to pass through.

[0014] In some embodiments, the lower end of the finely rolled threaded steel bar is provided with a lower waterproof structure.

[0015] In some embodiments, the lower waterproof structure includes a heat shrinkable tube, the upper section of which is sleeved on the lower end of the sleeve from bottom to top and connected to the lower end of the sleeve by wrapping with waterproof tape. The lower section of the heat shrinkable tube is heated and shrunk to fit against the fine-rolled threaded steel bar and then passes through the carrier and the fastening nut matching the carrier in sequence. The lower section of the heat shrinkable tube and the lower end of the fine-rolled threaded steel bar are then wrapped and sealed with waterproof tape. The lower waterproof structure also includes an expansion water-stop ring and an elastic rubber nut installed on the lower section of the fine-rolled threaded steel bar and adapted to the sleeve. The expansion water-stop ring is located below the elastic rubber nut.

[0016] In some embodiments, after the upper section of the heat shrink tube of the lower waterproof structure is heated and bonded to the sleeve, it is then wrapped and connected using waterproof tape.

[0017] Compared with the prior art, the present invention has the following beneficial effects: When prestress is applied to the anchor bolt of this invention, the elastic rubber nut of the upper waterproof structure moves along with the finely rolled threaded steel bar. On the one hand, the elastic rubber nut itself deforms to seal the inside of the casing; on the other hand, the elastic rubber nut compresses the expansion water-stop ring, causing the expansion water-stop ring to deform and seal the inside of the casing. That is, the expansion water-stop ring and the elastic rubber nut achieve a double seal inside the casing, so that the expansion water-stop ring plays a sealing role from the beginning. Together with the external heat shrink tube and waterproof tape, it achieves the purpose of improving the sealing effect, and ultimately improves the anti-corrosion effect and the durability of the anchor bolt.

[0018] The present invention ensures that the sealing effect between the heat shrink tube and the finely rolled threaded steel bar is not damaged due to the displacement of the finely rolled threaded steel bar when prestressing is applied, nor does the displacement of the finely rolled threaded steel bar affect the connection and sealing effect of the waterproof tape at the upper end of the heat shrink tube, thus ensuring that moisture does not enter the sleeve from the upper end of the heat shrink tube.

[0019] The waterproof structure of this invention involves applying prestress to the finely threaded steel bar before the heat-shrinkable tube is heated and sealed to the steel bar, and finally, the end of the heat-shrinkable tube is sealed and wrapped with waterproof tape. Firstly, the heat-shrinkable tube is inherently stronger than the waterproof tape, making it highly unlikely (almost nonexistent) to be damaged by impact during normal handling and lowering of the finely threaded steel bar. Secondly, the heat-shrinkable tube extending into the anchor hole and the waterproof tape at its upper end will not be damaged by pulling due to the applied prestress. Therefore, the sealing effect is improved in two ways.

[0020] This invention utilizes a prestressed cylinder to disperse the applied force, avoiding or reducing the risk of shear damage to the area corresponding to the foundation or base plate and the anchor hole, thereby improving the durability and service life of the anchor rod. Attached Figure Description

[0021] Figure 1 This is a structural schematic diagram of an embodiment of the present invention. In this schematic diagram, the anchor rod is an enlarged head anchor rod. The upper end of the enlarged head anchor rod is also provided with a spiral bar. The lower end of the spiral bar extends into the anchor body, and the upper section of the spiral bar extends into the foundation or bottom plate. Figure 2 This is a structural schematic diagram of another embodiment of the present invention. In this schematic diagram, the anchor rod is an anchor rod of equal diameter. In this schematic diagram, a spiral bar is sleeved on the upper part of the bearing body, and the lower end of the spiral bar is fixedly installed on the bearing body. Figure 3 This is a schematic diagram of the waterproof structure of the present invention; Figure 4 This is a schematic diagram of the lower waterproof structure of the present invention; The markings in the diagram are: 1. Fine-rolled threaded steel bar, 2. Load-bearing body, 21. Fastening nut, 3. Anchor body, 4. Spiral reinforcement, 5. Sleeve, 6. Prestressed anchor, 61. Prestressed anchor plate, 62. Prestressed anchor head, 7. Foundation or base plate, 8. Upper waterproof structure, 9. Lower waterproof structure, 10. Prestressed cylinder, 101. Pad, 11. Heat shrink tube, 12. Waterproof tape, 13. Elastic rubber nut, 14. Expansion sealing ring. Detailed Implementation

[0022] The present invention will be further described below with reference to embodiments. These embodiments are merely some, not all, of the embodiments of the present invention. Other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are all within the protection scope of the present invention.

[0023] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. The terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Furthermore, unless otherwise explicitly specified and limited, the terms "installed," "connected," and "joined" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0024] Combined with appendix Figure 1 To be continued Figure 4The pressure-type PSB prestressed anchor bolt of the present invention includes a finely rolled threaded steel bar 1. The lower bottom of the finely rolled threaded steel bar 1 is provided with a bearing body 2 and extends into the anchor hole. An anchor body 3 is formed in the anchor hole by casting. The upper end of the finely rolled threaded steel bar 1 extends upward into the foundation or base plate 7. The outer periphery of the finely rolled threaded steel bar 1 is provided with a sleeve 5 filled with anti-corrosion grease. Both the upper and lower ends of the finely rolled threaded steel bar 1 extend out of the sleeve 5. The upper end face of the sleeve 5 is flush with the upper end face of the anchor hole. The upper end of the finely rolled threaded steel bar 1 is provided with an upper waterproof structure 8.

[0025] In some embodiments, the upper waterproof structure 8 includes a heat shrinkable tube 11. The lower end of the heat shrinkable tube 11 is sleeved around the outer periphery of the sleeve 5 and connected to the sleeve 5 by wrapping with waterproof tape 12. The upper end of the heat shrinkable tube 11 is sleeved around the outer periphery of the fine-rolled threaded steel bar 1 and extends out of the anchor hole into the foundation or base plate 7. The upper end of the heat shrinkable tube 11 and the fine-rolled threaded steel bar 1 are connected by wrapping with waterproof tape 12. The upper waterproof structure 8 also includes an expansion water-stop ring 14 and an elastic rubber nut 13 installed on the upper section of the fine-rolled threaded steel bar 1 and adapted to the sleeve 5. The elastic rubber nut 13 is located below the expansion water-stop ring 14 and contacts the expansion water-stop ring 14. The upper end face of the expansion water-stop ring 14 is aligned with the upper end face of the anchor hole. When prestress is applied to the anchor rod of this invention, the elastic rubber nut moves along with the finely rolled threaded steel bar. On the one hand, the elastic rubber nut deforms itself, thereby sealing the inside of the casing. On the other hand, the elastic rubber nut compresses the expansion water-stop ring, causing the expansion water-stop ring to deform and seal the inside of the casing. That is, the expansion water-stop ring and the elastic rubber nut achieve a double seal inside the casing, so that the expansion water-stop ring plays a sealing role from the beginning. Together with the external heat shrink tube and waterproof tape, it achieves the purpose of improving the sealing effect.

[0026] In some embodiments, the heat shrinkable tube 11 located around the sleeve 5 in the upper waterproof structure 8 is heated and then bonded to the sleeve 5 before being wrapped with waterproof tape 12. The heat shrinkable tube 11 corresponding to the sleeve 5 (i.e., the lower section of the heat shrinkable tube) can be tightly bonded to the sleeve 5 after heating to achieve a certain sealing effect. Then, the lower end of the heat shrinkable tube is sealed and wrapped with waterproof tape to prevent moisture from entering from the lower end of the heat shrinkable tube.

[0027] In some embodiments, the heat shrinkable tube 11 corresponding to the upper end of the anchor hole in the upper waterproof structure 8, after heating, serves to limit the expansion sealing ring 14. In specific implementation, the position of the heat shrinkable tube 11 corresponding to the anchor hole can be appropriately heated so that the heat shrinkable tube 11 at that location can both limit the expansion sealing ring 14 and prevent contact with the finely threaded steel bar 1. When heating the heat shrinkable tube, construction personnel can visually observe the amount of deformation. Therefore, those skilled in the art can control the amount of deformation of the heat shrinkable tube by controlling the heating time, thus ensuring that the heat shrinkable tube extending out of the anchor hole can both limit the expansion sealing ring and prevent contact with the finely threaded steel bar extending out of the anchor hole. Therefore, when prestress is applied to the finely threaded steel bar, the heat shrinkable tube extending out of the anchor hole will not be pulled by the finely threaded steel bar.

[0028] In some embodiments, the heat shrinkable tube 11 extending out of the anchor hole is heated after prestressing is applied to the threaded steel bar 1, thereby bonding it to the threaded steel bar 1; the upper end of the heat shrinkable tube 11 is then wrapped and connected to the threaded steel bar 1 by waterproof tape 12 after prestressing is applied. This ensures that the sealing effect between the heat shrinkable tube and the threaded steel bar is not damaged due to displacement of the threaded steel bar during prestressing, nor is the connection and sealing effect of the waterproof tape at the upper end of the heat shrinkable tube affected by the displacement of the threaded steel bar, thus ensuring that moisture does not enter the sleeve from the upper end of the heat shrinkable tube.

[0029] In existing technologies, waterproof tape is generally wrapped directly around the outer perimeter of the threaded steel bar. For the upper section of the threaded steel bar, although the waterproof tape itself is elastic and there are many wrappings, the threaded steel bar will be displaced due to tension when prestressing is applied, which reduces the waterproof effect of the waterproof tape wrapped around the threaded steel bar, and may even cause the waterproof tape to break, thus greatly reducing the waterproof effect.

[0030] In this invention, the upper waterproof structure 8 involves prestressing the fine-rolled threaded steel bar 1 before the heat-shrinkable tube 11 is heated and sealed to the fine-rolled threaded steel bar. Finally, the end of the heat-shrinkable tube 11 is sealed and wrapped with waterproof tape 12. On one hand, the heat-shrinkable tube 11 is stronger than the waterproof tape, so the probability of it being damaged by impact during normal handling and lowering of the fine-rolled threaded steel bar 1 is very low (almost non-existent). On the other hand, the heat-shrinkable tube 11 extending out of the anchor hole and the waterproof tape 12 at its upper end will not be damaged by pulling due to the applied prestress. Therefore, the sealing effect is improved in two ways.

[0031] In some embodiments, the fine-rolled threaded steel bar 1 is equipped with a cylindrical prestressing cylinder 10, and the circumferential arm of the prestressing cylinder 10 has multiple strip-shaped operating windows for the passage of waterproof tape 12. The prestressing cylinder 10, together with the prestressing anchor 6 (generally including a prestressing anchor plate 61 and a prestressing anchor head 62) provided with the fine-rolled threaded steel bar 1, locks the prestress of the fine-rolled threaded steel bar 1, preventing prestress loss. Simultaneously, the structural design of the prestressing cylinder does not affect the heating and shrinking of the heat-shrinkable tube extending from the anchor hole or the wrapping of the waterproof tape; furthermore, compared to the prior art's use of spiral reinforcement 4, the prestressing cylinder 10 provides a more significant strengthening effect.

[0032] Since the nozzle size of the heating gun used to heat the heat shrink tubing is generally smaller than the width of the waterproof tape, it is sufficient to ensure that the waterproof tape passes through. The purpose of setting multiple strip-shaped operating windows is to heat the heat shrink tubing from different positions, thereby ensuring that the circumference of the heat shrink tubing extending out of the anchor hole can be heated and shrunk to fit against the finely rolled threaded steel bar; at the same time, multiple strip-shaped operating windows also facilitate the wrapping of waterproof tape.

[0033] In some embodiments, the prestressed cylinder 10 may also be a split design, for example, the prestressed cylinder may consist of 2-4 plates (arc-shaped plates, L-shaped plates, flat plates, etc.), with operating windows formed between adjacent plates for the passage of waterproof tape and heating gun heads. This will be understood by those skilled in the art and will not be elaborated further here.

[0034] In the specific implementation process, after the fine-rolled threaded steel bar 1 is prestressed, the prestressing cylinder 10 is cast together in the foundation or base slab 7. The prestressing cylinder 10 disperses the force, avoiding or reducing the risk of shear damage to the area corresponding to the anchor hole in the foundation or base slab, thereby improving the durability and service life of the anchor rod. The strip-shaped operating window also serves as a channel for concrete to enter during the pouring of the foundation or base slab.

[0035] Preferably, the prestressed cylinder 10 is provided with several through holes on its outer circumference, which further improves the speed of concrete flow when pouring the foundation or base slab 7.

[0036] In a preferred embodiment of the present invention, a pad 101 is provided at the bottom of the prestressed cylinder 10, and a through hole is provided in the middle of the pad 101 for the heat shrink tube 11 and the fine-rolled threaded steel bar 1 to pass through. The pad further increases the stress-bearing area, thereby further reducing the probability of shear damage to the area corresponding to the foundation or bottom plate and the anchor hole, ultimately improving the durability and service life of the anchor rod.

[0037] In some embodiments, the lower end of the finely rolled threaded steel bar 1 is provided with a lower waterproof structure 9.

[0038] In some embodiments, the lower waterproof structure 9 includes a heat shrinkable tube 11. The upper section of the heat shrinkable tube 11 is sleeved on the lower end of the sleeve 5 from bottom to top and connected to the lower end of the sleeve by a waterproof tape 12. The lower section of the heat shrinkable tube 11 is heated and shrunk to fit against the fine-rolled threaded steel bar 1 and then passes through the carrier body 2 and the fastening nut 21 of the carrier body in sequence. The lower section of the heat shrinkable tube 5 and the lower end of the fine-rolled threaded steel bar 1 are then sealed and connected by a waterproof tape 12. The lower waterproof structure 9 also includes an expansion water-stop ring 14 and an elastic rubber nut 13 installed on the lower section of the fine-rolled threaded steel bar 1 and adapted to the sleeve 5. The expansion water-stop ring 14 is located below the elastic rubber nut 13.

[0039] In some embodiments, after the upper section of the heat-shrinkable tube 11 of the lower waterproof structure 9 is heated and bonded to the sleeve 5, it is then connected by wrapping with waterproof tape 12. The initial seal is achieved by the heat-shrinkable tube being heated and bonded to the sleeve, followed by a secondary seal using the wrapped waterproof tape, thus preventing moisture from entering from the upper part of the lower waterproof structure. Similarly, the initial seal is achieved by the heat-shrinkable tube being heated and bonded to the lower end of the precision-rolled threaded steel bar, followed by a secondary seal using the wrapped waterproof tape, thus preventing moisture from entering from the bottom of the lower waterproof structure. Finally, when the anchor rod is under stress, the elastic rubber nut compresses the expansion sealing ring, and the secondary seal of the expansion sealing ring and the elastic rubber nut prevents moisture from entering the sleeve, thereby ensuring the corrosion protection effect of the lower part of the precision-rolled threaded steel bar.

[0040] In summary, the heat shrink tube of the lower waterproof structure 9 of the present invention is stronger than the waterproof tape. The probability of it being damaged by collision during normal handling and lowering of the fine-rolled threaded steel bar is very low (almost non-existent). At the same time, the elastic rubber nut and the expansion sealing ring are always in a sealed working state. Compared with the waterproof structure of the prior art, it can improve the waterproof effect at the bottom of the fine-rolled threaded steel bar.

[0041] In the specific implementation process, after the space between the sleeve 5 and the fine-rolled threaded steel bar 1 is filled with anti-corrosion grease, elastic rubber nuts 14 and expansion water-stop rings 13 are inserted from both ends of the sleeve 5, thereby using the anti-corrosion grease to cover and protect the fine-rolled threaded steel bar 1. The sealing effect of the elastic rubber nuts 13 and expansion water-stop rings 14 can prevent the anti-corrosion grease from seeping out of the sleeve 5 under the action of gravity, and can also prevent external moisture from entering the sleeve 5.

[0042] Preferably, the finely rolled threaded steel bar 1 is also coated with anti-corrosion paint to further improve the anti-corrosion effect. The anti-corrosion paint can be applied at the factory.

Claims

1. A pressure-type PSB prestressed anchor bolt, comprising a finely threaded steel bar, wherein a bearing body is provided at the lower bottom of the finely threaded steel bar and extends into an anchor hole, the upper end of the finely threaded steel bar extends upward into the foundation or base slab, and a sleeve filled with anti-corrosion grease is fitted around the finely threaded steel bar, with both the upper and lower ends of the finely threaded steel bar extending out of the sleeve, characterized in that, The upper end face of the sleeve is flush with the upper end face of the anchor hole, and the upper end of the fine-rolled threaded steel bar is equipped with an upper waterproof structure. The upper waterproof structure includes a heat shrinkable tube. The lower end of the heat shrinkable tube is sleeved around the outer periphery of the sleeve and connected to the sleeve by wrapping with waterproof tape. The upper end of the heat shrinkable tube is sleeved around the outer periphery of the fine-rolled threaded steel bar and extends out through the anchor hole into the foundation or base plate. The upper end of the heat shrinkable tube and the fine-rolled threaded steel bar are connected by wrapping with waterproof tape. The upper waterproof structure also includes an expansion water-stop ring and an elastic rubber nut installed on the upper section of the fine-rolled threaded steel bar and adapted to the sleeve. The elastic rubber nut is located below the expansion water-stop ring and contacts the expansion water-stop ring. The upper end face of the expansion water-stop ring is aligned with the upper end face of the anchor hole.

2. The pressure-type PSB prestressed anchor bolt according to claim 1, characterized in that, After the heat shrink tubing located on the outside of the sleeve is heated and bonded to the sleeve, it is then wrapped and connected using waterproof tape.

3. The pressure-type PSB prestressed anchor bolt according to claim 2, characterized in that, The heat shrink tube corresponding to the upper end of the anchor hole, after being heated, plays a limiting role in the expansion sealing ring.

4. The pressure-type PSB prestressed anchor bolt according to claim 3, characterized in that, The heat shrink tube extending out of the anchor hole is heated after applying prestress to the fine-rolled threaded steel bar to fit it; the upper end of the heat shrink tube is then wrapped and connected to the fine-rolled threaded steel bar with waterproof tape after applying prestress to it.

5. The pressure-type PSB prestressed anchor bolt according to claim 4, characterized in that, The fine-rolled threaded steel bar is equipped with a cylindrical prestressed cylinder, and the circumferential arm of the prestressed cylinder has multiple strip-shaped operating windows for waterproof tape to pass through.

6. The pressure-type PSB prestressed anchor bolt according to claim 5, characterized in that, After the finely rolled threaded steel bars are prestressed, the prestressed cylinder is cast together in the foundation or base slab.

7. The pressure-type PSB prestressed anchor bolt according to any one of claims 1-6, characterized in that, The lower end of the fine-rolled threaded steel bar is equipped with a waterproof structure.

8. The pressure-type PSB prestressed anchor bolt according to claim 7, characterized in that, The lower waterproof structure includes a heat-shrinkable tube. The upper section of the heat-shrinkable tube is fitted over the lower end of the sleeve from bottom to top and connected to the lower end of the sleeve by wrapping with waterproof tape. The lower section of the heat-shrinkable tube is heated and shrunk to fit against the fine-rolled threaded steel bar and then passes through the bearing body and the fastening nut matching the bearing body. The lower section of the heat-shrinkable tube and the lower end of the fine-rolled threaded steel bar are then wrapped and sealed with waterproof tape. The lower waterproof structure also includes an expansion water-stop ring and an elastic rubber nut installed on the lower section of the fine-rolled threaded steel bar and adapted to the sleeve. The expansion water-stop ring is located below the elastic rubber nut.

9. The pressure-type PSB prestressed anchor bolt according to claim 8, characterized in that, After the upper section of the heat shrink tube of the lower waterproof structure is heated and bonded to the sleeve, it is then wrapped and connected with waterproof tape.

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