Low-retraction anchoring device for prestressed reinforcement
By using a casing to fix it on the inner wall of the sealing cylinder in the prestressed steel bar anchoring device, ensuring that the prestressed steel bars are coaxially perpendicular to the anchor pad plate, the problems of large prestress loss and large structural size are solved, and small retraction and Efficient construction.
Patent Information
- Application Number
- CN202421161269.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-24
- Publication Date
- 2025-01-14
- Estimated Expiration
- 2034-05-24
AI Technical Summary
In prestressed construction, it is difficult to ensure coaxial and verticality of the prestressed steel bars and the tensioned end anchor pads, resulting in large amounts of retraction and high prestress loss, especially in bridge projects, anchor retraction loss reaches 20% to 40% , and the secondary tension prestressed anchor structure size is relatively large, and the notch size also needs to be larger when applied to high-strength concrete.
Design a low retraction anchoring device for prestressed steel bars, including tensioning end anchor pads, anchors, prestressed steel bars, sealing cylinders and sleeves. The sleeve is fixed to the inner wall of the sealing cylinder, and the prestressed steel bars pass through the sleeves. To ensure neutralization and perpendicularity, the sleeve is provided with a slurry passage in the axial direction for grouting.
It reduces anchor retraction losses, reduces structural size, improves construction accuracy and efficiency, ensures smooth grouting, and is simple in structure and low in cost.
Smart Images
Figure CN222350054U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a prestressed anchoring device, in particular to a low-retraction anchoring device for prestressed steel bars. Background Art
[0002] In actual prestressed construction, it's difficult to ensure the prestressed steel bars are coaxial with the openings in the tensioning anchor pads, nor are they perpendicular to the end faces of the tensioning anchor pads. Large deviations can even occur, leading to significant shrinkage of the prestressed steel bars after tensioning and anchoring, significant prestress loss, and low steel utilization. In particular, vertical prestressed anchors in bridges experience shrinkage losses of up to 20% to 40%. While secondary prestressed anchors have been successfully developed to effectively address this issue, they are relatively large, and the reserved tensioning notches in high-strength concrete are also large. Summary of the Invention
[0003] The technical problem to be solved by the utility model is to provide a low-retraction anchoring device for prestressed steel bars, so as to solve the technical problems of large prestress loss and large structural size in the prior art.
[0004] The technical solution to solve the above technical problems is: a low-retraction anchoring device for prestressed steel bars, including a tensioning end anchor plate, an anchor, prestressed steel bars, a sealing tube, and an embedded pipe; a sleeve is also coaxially installed in the sealing tube, which is fixed on the inner wall of the sealing tube, and the prestressed steel bars pass through the sleeve.
[0005] A further technical solution of the present invention is that: there is one or more than two sleeves. When there are more than two sleeves, each sleeve is fixed on the inner wall of the sealing cylinder at the same interval along the axial direction of the sealing cylinder.
[0006] A further technical solution of the present invention is that arc chamfers are provided at both ends of the inner hole of the sleeve.
[0007] A further technical solution of the present invention is that the sleeve is further provided with a slurry passage along its axial direction.
[0008] A further technical solution of the present invention is that: there is one or more than two slurry passages, and each slurry passage is arranged in the tube wall between the inner wall and the outer surface of the sleeve along the axial direction of the sleeve.
[0009] Due to the above structure, the low-retraction anchoring device for prestressed steel bars of the present invention has the following beneficial effects compared with the prior art:
[0010] 1. Small anchoring shrinkage loss
[0011] The utility model adds one or more sleeves to the sealing cylinder, which are fixed to the inner wall of the sealing cylinder, and the prestressed steel bars pass through the sleeves. The sleeves ensure that the prestressed steel bars are aligned with the pre-buried channel and perpendicular to the end face of the tensioning end anchor plate. After the anchor is tensioned and tightened, the lower end face of the anchor is fully aligned with the tensioning end anchor plate, ensuring accurate installation and positioning during construction, thereby reducing the shrinkage of the prestressed steel bars after tensioning and anchoring.
[0012] In addition, even if there is a deviation in the fit between the prestressed steel bars passing through the entire device, it can be controlled within the allowable range through the sleeve, so that the final anchor retraction meets the requirements.
[0013] 2. Small structure size
[0014] The utility model reduces the shrinkage of the prestressed steel bars after tensioning and anchoring by adding one or more sleeves in the sealing cylinder, without increasing the structural size or adopting a large-sized secondary tensioning prestressed anchor, thereby solving the technical problem of the prior art that a large-sized tensioning groove needs to be reserved in high-strength concrete.
[0015] 3. Reasonable design
[0016] The sleeve of the utility model is also provided with one or more slurry passages along its axial direction, which can ensure that slurry can pass through smoothly during grouting, and its structure is relatively reasonable.
[0017] 4. Easy to construct
[0018] By adding one or more sleeves in the sealing cylinder, the utility model enables the prestressed steel bars to be tensioned only after passing through the entire device during construction, without the need for deliberate centering or deviation correction, which greatly facilitates the construction process, effectively shortens the construction time, and ensures efficient and accurate construction.
[0019] 5. Simple structure, low cost, easy to promote and apply.
[0020] The technical features of the low-retraction anchoring device for prestressed steel bars of the present invention will be further described below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 : A schematic structural diagram of a low-retraction anchoring device for prestressed steel bars according to the utility model in accordance with the first embodiment.
[0022] Figure 2 : A schematic structural diagram of the sleeve described in Example 1,
[0023] Figure 3 : Figure 2 A top view of
[0024] Figure 4 : A schematic structural diagram of a low-retraction anchoring device for prestressed steel bars according to the second embodiment of the present invention.
[0025] Figure 5 : A schematic structural diagram of the sleeve described in Example 2,
[0026] Figure 6 : Figure 5 A top view of
[0027] Figure 7 : A schematic structural diagram of a low-retraction anchoring device for prestressed steel bars according to the utility model in accordance with the third embodiment.
[0028] Figure 8 : A schematic structural diagram of the sleeve described in Example 3,
[0029] Figure 9 : Figure 8 A top view of
[0030] In the above drawings, the descriptions of the reference numerals are as follows:
[0031] 1-tension end anchor plate, 2-anchor, 3-prestressed steel bar, 4-spiral bar,
[0032] 5- casing, 501- slurry passage, 6- sealing cylinder, 601- sealing device, 7- embedded pipe. DETAILED DESCRIPTION Example 1:
[0033] Figure 1 Disclosed is a low-retraction anchoring device for prestressed steel bars, comprising a tensioning end anchor plate 1, an anchor 2, a prestressed steel bar 3, a spiral bar 4, a sleeve 5, a sealing tube 6, and a pre-buried pipe 7; wherein:
[0034] The tensioning end anchor plate 1 is pre-buried at the tensioning end opening of the pre-buried channel, the anchor 2 is anchored on the prestressed steel bar 3, and the lower end face of the anchor 2 is fully fitted with the upper end face of the tensioning end anchor plate 1. The sealing tube 6 is installed in the pre-buried channel, and the upper end of the sealing tube 6 is welded and fixed to the lower end face of the tensioning end anchor plate 1. The spiral rib 4 is installed on the outside of the sealing tube 6, and a conventional sealing device 601 is installed on the bottom of the sealing tube 6. A sleeve 5 is coaxially welded and fixed on the inner wall of the sealing tube 6, and the prestressed steel bar 3 passes through the sleeve 5. The length and inner hole diameter of the sleeve 5 are set according to the needs of the actual construction project; both ends of the inner hole of the sleeve 5 are also provided with arc chamfers to avoid scratching the prestressed steel bar 3; the sleeve 5 is also provided with a slurry passage 501 along its axial direction, and the slurry passage 501 is provided in the pipe wall between the inner wall and the outer surface of the sleeve 5 along the axial direction of the sleeve 5 (see Figure 2-Figure 3), to ensure that the slurry can pass smoothly during grouting. The embedded pipe 7 is installed in the embedded channel below the sealing cylinder 6 and is fixedly connected to the lower end of the sealing cylinder 6. The lower end of the prestressed steel bar 3 passes through the embedded pipe 7. Example 2:
[0035] Figure 4 Disclosed herein is another low-retraction anchoring device for prestressed steel bars. Its basic structure is the same as that of the first embodiment, including a tensioning end anchor plate 1, an anchor 2, a prestressed steel bar 3, a spiral bar 4, a sleeve 5, a sealing tube 6, and a pre-buried tube 7. The difference is that there are two sleeves 5, which are fixed to the inner wall of the sealing tube 6 at a certain interval along the axial direction. There are two slurry passages 501, which are respectively arranged in the tube wall between the inner wall and the outer surface of the sleeve 5 along the axial direction (see Figure 5-Figure 6 ).
[0036] The specific structure of the low-retraction anchoring device for prestressed steel bars described in the second embodiment is as follows:
[0037] A low-retraction anchoring device for prestressed steel bars, comprising a tensioning end anchor plate 1, an anchor 2, a prestressed steel bar 3, a spiral bar 4, a sleeve 5, a sealing tube 6, and a pre-buried pipe 7; wherein:
[0038] The tensioning end anchor plate 1 is pre-buried at the tensioning end opening of the pre-buried channel, the anchor 2 is anchored on the prestressed steel bar 3, and the lower end surface of the anchor 2 is fully fitted with the upper end surface of the tensioning end anchor plate 1. The sealing cylinder 6 is installed in the embedded channel. The upper end of the sealing cylinder 6 is welded and fixed on the lower end face of the tensioning end anchor plate 1. The spiral rib 4 is installed on the outside of the sealing cylinder 6. The bottom of the sealing cylinder 6 is installed with a conventional sealing device 601. Two sleeves 5 are welded and fixed on the inner wall of the sealing cylinder 6 at a certain interval along the axial direction. The prestressed steel bar 3 passes through the sleeve 5. The length and inner hole diameter of the sleeve 5 are set according to the needs of the actual construction project. The inner hole of the sleeve 5 is also provided with arc chamfers at both ends to avoid scratching the prestressed steel bar 3. The sleeve 5 is also provided with two slurry passages 501 along its axial direction. The two slurry passages 501 are respectively arranged in the pipe wall between the inner wall and the outer surface of the sleeve 5 along the axial direction of the sleeve 5 to ensure that the slurry can pass smoothly during grouting. The embedded pipe 7 is installed in the embedded channel below the sealing cylinder 6 and is fixedly connected to the lower end of the sealing cylinder 6. The lower end of the prestressed steel bar 3 passes through the embedded pipe 7. Example 3:
[0039] Figure 7Disclosed herein is another low-retraction anchoring device for prestressed steel bars. Its basic structure is the same as that of the second embodiment, including a tensioning end anchor plate 1, an anchor 2, a prestressed steel bar 3, a spiral bar 4, a sleeve 5, a sealing tube 6, and a pre-buried tube 7. The difference is that there are three sleeves 5, which are fixed to the inner wall of the sealing tube 6 at a certain interval along the axial direction. There are three slurry passages 501, which are respectively arranged in the tube wall between the inner wall and the outer surface of the sleeve 5 along the axial direction (see Figure 8-Figure 9 ).
[0040] The specific structure of the low-retraction anchoring device for prestressed steel bars described in the third embodiment is as follows:
[0041] A low-retraction anchoring device for prestressed steel bars, comprising a tensioning end anchor plate 1, an anchor 2, a prestressed steel bar 3, a spiral bar 4, a sleeve 5, a sealing tube 6, and a pre-buried pipe 7; wherein:
[0042] The tensioning end anchor plate 1 is pre-buried at the tensioning end opening of the pre-buried channel, the anchor 2 is anchored on the prestressed steel bar 3, and the lower end surface of the anchor 2 is fully fitted with the upper end surface of the tensioning end anchor plate 1. The sealing cylinder 6 is installed in the embedded channel. The upper end of the sealing cylinder 6 is welded and fixed on the lower end face of the tensioning end anchor plate 1. The spiral rib 4 is installed on the outside of the sealing cylinder 6. The bottom of the sealing cylinder 6 is installed with a conventional sealing device 601. Three sleeves 5 are welded and fixed on the inner wall of the sealing cylinder 6 at a certain interval along the axial direction. The prestressed steel bar 3 passes through the sleeve 5. The length and inner hole diameter of the sleeve 5 are set according to the needs of the actual construction project. The inner hole of the sleeve 5 is also provided with arc chamfers at both ends to avoid scratching the prestressed steel bar 3. The sleeve 5 is also provided with three slurry passages 501 along its axial direction. The three slurry passages 501 are respectively arranged in the pipe wall between the inner wall and the outer surface of the sleeve 5 along the axial direction of the sleeve 5 to ensure that the slurry can pass smoothly during grouting. The embedded pipe 7 is installed in the embedded channel below the sealing cylinder 6 and is fixedly connected to the lower end of the sealing cylinder 6. The lower end of the prestressed steel bar 3 passes through the embedded pipe 7.
[0043] As a variation of the above-mentioned embodiments 1, 2, and 3, the sleeves 5 may be four, five, or more in number, each of which is fixed to the inner wall of the sealing tube 6 at a certain interval along the axial direction of the sealing tube 6. The slurry passages 501 may also be four, five, or more in number, each of which is disposed in the tube wall between the inner wall and the outer surface of the sleeve 5 along the axial direction of the sleeve 5.
[0044] The working principle of this utility model is as follows:
[0045] When the present invention is in use, the prestressed steel bar 3 is passed through the entire device (tensioning end anchor plate 1, sleeve 5, embedded pipe 7) normally. Under the constraints of the two end openings of the sleeve 5 and the inner hole of the sleeve 5, the prestressed steel bar 3 and the sleeve 5 cannot form an eccentricity exceeding the allowable range or an angle that is not perpendicular to the end face of the tensioning end anchor plate 1. When the prestressed steel bar 3 is tensioned to the design force, the anchor 2 (i.e., the tensioning nut) is tightened, and then tensioning is performed. Because the present invention ensures that the prestressed steel bar 3 is aligned with the embedded channel and perpendicular to the end face of the tensioning end anchor plate 1, tightening the anchor 2 (i.e., the tensioning nut) after tensioning it into place can make the anchor 2 (i.e., the tensioning nut) fully fit with the tensioning end anchor plate 1, achieving the effect of reducing the shrinkage of the prestressed steel bar 3 after tensioning.
Claims
1. A low-retraction anchoring device for prestressed steel bars, comprising a tensioning end anchor pad (1), an anchor (2), a prestressed steel bar (3), a sealing cylinder (6), and a pre-buried pipe (7); characterized in that: A sleeve (5) is also coaxially installed in the sealing cylinder (6); the sleeve (5) is fixed on the inner wall of the sealing cylinder (6), and the prestressed steel bar (3) passes through the sleeve (5).
2. A low-retraction anchoring device for prestressed steel bars according to claim 1, characterized in that: There is one or more than two sleeves (5). When there are more than two sleeves (5), each sleeve (5) is fixed on the inner wall of the sealing tube (6) at the same interval along the axial direction of the sealing tube (6).
3. A low-retraction anchoring device for prestressed steel bars according to claim 1, characterized in that: Both ends of the inner hole of the sleeve (5) are also provided with circular arc chamfers.
4. A low-retraction anchoring device for prestressed steel bars according to claim 1, 2 or 3, characterized in that: The sleeve (5) is also provided with a slurry passage (501) along its axial direction.
5. A low-retraction anchoring device for prestressed steel bars according to claim 4, characterized in that: There is one or more than two slurry passage channels (501), and each slurry passage channel (501) is arranged in the tube wall between the inner wall and the outer surface of the sleeve (5) along the axial direction of the sleeve (5).