Prestressed clamping piece set and anchoring device

Abstract

The utility model relates to a pre-stressed clamping piece group and anchoring device, applied to pre-stressed anchorage device, pre-stressed clamping piece group includes at least two clamping piece's circular tubular structure, the circular tubular structure includes circular tube portion and circular truncated cone portion, the outer diameter of circular truncated cone portion gradually decreases along the direction close to circular tube portion to away from circular tube portion, and the circular truncated cone portion has the circular tube portion and the circular truncated cone portion has the circular tube portion and the circular truncated cone portion. An inner cavity of the prestress clamping piece set sequentially comprises a steel strand passing cavity, a steel strand clamping cavity and a stress release cavity in the direction from the circular pipe part to the circular truncated cone part, a first internal thread is arranged in the steel strand clamping cavity, a second internal thread is arranged in the stress release cavity, a stress release groove is formed in the outer side of each clamping piece, and the stress release groove is communicated with the first internal thread. And a plurality of stress release grooves are uniformly distributed on the outer side of the central axis of the prestressed clamping piece group in a star shape. The effective clamping position between the tool clamping piece set and the clamped steel strand after tensioning is improved. The utility model has the advantages of convenient use and wide market prospect.

Description

Technical Field

[0001] The utility model relates to the field of prestressed clamps, in particular to a prestressed clip group and an anchoring device. Background Art

[0002] When casting prestressed concrete components for buildings such as long-span bridges, industrial plants, and dams, a prestressed anchor system is often used to apply prestress to the steel bars and strands. Anchors, a component of the prestressed anchor system, can be divided into four types: clip, support, cone, and grip. Clip anchors are the most commonly used. The anchoring efficiency coefficient is an important parameter in the performance of prestressed clips; 𝜂 a =F apu / F pm ; where 𝜂 a : Anchoring efficiency coefficient; F apu : Measured ultimate tensile force of the strand-anchor assembly, unit: kN; F pm : The actual average ultimate tensile strength of the steel strand is equal to the measured average tensile strength of the steel strand × the total number of steel strands, unit: kN.

[0003] The characteristics of the post-tensioning method are that the components are made first, the channels are made and grouting is done later, and then the channels are reserved in advance. When the concrete component reaches the set value, the prestressed tendons are inserted into the reserved channels, tensioned by tensioning equipment, and the tensioned prestressed tendons are fixed to the ends of the components with anchors. During the construction of post-tensioning prestressed tendons, the tools and equipment must be calibrated and tested in advance, the anchors must be cleaned, and there must be no foreign matter at the ends of the steel bundles to reduce the occurrence of slippage. The slippage is the relative movement between the tool clips and the steel strands due to the insufficient clamping force of the tool clips after tensioning. Once the slippage occurs, the retraction of the steel strands will increase, and the tensioned bridge will not reach the designed load-bearing capacity.

[0004] Among them, the main reasons for the occurrence of the thread slippage phenomenon are as follows: First, due to improper cleaning of the anchor, foreign matter is embedded between the steel strand and the anchor clip, thereby damaging the threaded surface on the anchor clip, reducing the friction coefficient between the steel strand and the clip, and thus reducing the maximum static friction between the steel strand and the clip; second, due to the difference between the inner cavity diameter of the tool clip group formed by several clips and the circumscribed circle diameter of the clamped steel strand, the tangent position between the inner cavity of each tool clip and the clamped steel strand is the effective clamping position. The commercially available tool clip groups are usually two-piece or three-piece types, and the use of two-piece tool clip groups or three-piece tool clip groups is for the convenience of on-site installation. Therefore, there is room for improvement in the existing technology, which aims to make basic structural improvements to the existing commercially available tool clip sets, so as to take into account the needs of easy installation of the clips on site and the ability to increase the effective clamping position of the clamped steel strands after tensioning, so as to reduce the occurrence of wire slippage in the tool clip set and the clamped steel strands, and thereby reduce the retraction of the steel strands after tensioning. Summary of the Invention

[0005] In view of the deficiencies in the prior art, the present invention provides a prestressed clamping piece group and an anchoring device that can improve the effective clamping position between the tool clamping piece group and the clamped steel strand after tensioning, so as to overcome the defects in the prior art.

[0006] The technical solution adopted by the present invention is: a prestressed clip group, applied to a prestressed anchor, the prestressed clip group includes a circular tubular structure composed of at least two clips, the circular tubular structure includes a circular tube portion and a truncated cone portion, the outer diameter of the truncated cone portion gradually decreases along the direction from close to the circular tube portion to away from the circular tube portion, the inner cavity of the prestressed clip group includes a steel strand passing cavity, a steel strand clamping cavity and a stress release cavity in sequence along the direction from the circular tube portion to the truncated cone portion, a first internal thread is provided in the steel strand clamping cavity, a second internal thread is provided in the stress release cavity, a stress release groove is respectively provided on the outer side of each clip, and the number of stress release grooves is several, and the several stress release grooves are evenly distributed in a star shape on the outer side of the central axis of the prestressed clip group.

[0007] Preferably, an O-ring installation groove is provided on the outer side of the circular tube portion, and an O-ring is provided in the O-ring installation groove.

[0008] Preferably, the steel strand passing cavity and the steel strand clamping cavity are both cylindrical, the diameter of the steel strand passing cavity is not less than the diameter of the steel strand clamping cavity, an arc transition is used between the steel strand passing cavity and the steel strand clamping cavity, and the taper of the stress release cavity gradually increases as the stress release cavity gradually moves away from the steel strand clamping cavity.

[0009] An anchoring device comprises a porous anchor ring, which comprises an anchor ring body and a plurality of anchor holes opened on the anchor ring body, each of the anchor holes is respectively installed with a prestressed clip group as described above, a limiting plate is provided on one side of the porous anchor ring, a steel strand passing hole is respectively provided on the limiting plate on one side of each anchor hole, a plurality of threaded rods are provided on the limiting plate and the anchor ring body, and a fastening nut is respectively provided on each threaded rod on both sides of the limiting plate.

[0010] Preferably, each of the threaded rods is provided with a groove, a scale layer is provided in the groove, and the scale layer extends in a direction from close to the porous anchor ring to away from the porous anchor ring.

[0011] Preferably, the central axis of the limiting plate and the central axis of the porous anchor ring are located on the same axis, and several threaded rods are evenly distributed in a star shape on the outside of the central axis of the porous anchor ring. Each threaded rod is threadedly connected to the anchor ring body, and each threaded rod is respectively provided with a locking nut, and several locking nuts are fit with the anchor ring body.

[0012] The beneficial effects of the present invention are as follows: first, in the process of gradually tensioning the steel strands, as the tensioning amplitude of the tensioned steel strands gradually increases, when the tensioning amplitude of the tensioned steel strands reaches a preset range, since a number of stress release grooves are provided on each clip, each clip undergoes complete stress or stress fracture under the action of the stress release grooves, thereby increasing the effective clamping position of the clamped steel strands and reducing the phenomenon of too few effective clamping positions between the prestressed clip group and the clamped steel strands caused by the difference between the diameter of the inner cavity of the prestressed clip group and the diameter of the circumscribed circle of the clamped steel strands; further, before the clamped steel strands are tensioned, the number of clips in the prestressed clip group remains consistent with that of the commercially available two-piece clip group or three-piece clip group, thereby not increasing the difficulty of the initial installation of the clips.

[0013] Secondly, the outer side of the circular tube portion of the utility model is provided with an O-ring installation groove, and an O-ring is provided in the O-ring installation groove; installing the O-ring facilitates limiting the relative positions of the plurality of clips.

[0014] Again, each threaded rod described in the present invention is respectively provided with a groove, and a scale layer is provided in the groove, and the scale layer extends along the direction from close to the porous anchor ring to away from the porous anchor ring; the scale layer is provided to facilitate feedback of the distance between the limit plate and the porous anchor ring, thereby facilitating the use of several fastening nuts to adjust the relative position of the limit plate, thereby making the limit plate reach the preset installation position.

[0015] The utility model has the advantages of simple structure, convenient operation, ingenious design, greatly improved work efficiency, good social and economic benefits, and is a product that is easy to promote and use. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic diagram of the cross-sectional structure of the prestressed clip group of the present invention.

[0017] Figure 2 It is a schematic diagram of the three-dimensional structure of the prestressed clip group of the utility model.

[0018] Figure 3 It is a structural schematic diagram of the anchoring device of the present utility model.

[0019] Figure 4 It is a schematic diagram of the three-dimensional structure of the anchoring device of the present invention.

[0020] Figure 5 for Figure 4 A partially enlarged schematic diagram of detail A.

[0021] Figure 6 This is a schematic diagram of the anchoring device of the utility model in use. DETAILED DESCRIPTION

[0022] Example 1: Figure 1 and Figure 2 As shown, a prestressed clip group is applied to a prestressed anchor, the prestressed clip group includes a circular tubular structure composed of two clips 1 or three clips 1, the circular tubular structure includes a circular tube portion and a truncated cone portion, the outer diameter of the truncated cone portion gradually decreases along the direction from the circular tube portion to the direction away from the circular tube portion, the inner cavity of the prestressed clip group includes a steel strand passing cavity 2, a steel strand clamping cavity 3 and a stress release cavity 4 in sequence along the direction from the circular tube portion to the truncated cone portion, a first internal thread 5 is provided in the steel strand clamping cavity 3, and a second internal thread 6 is provided in the stress release cavity 4, and a stress release groove 7 is respectively provided on the outer side of each clip 1, and the number of stress release grooves 7 is several, and the several stress release grooves 7 are evenly distributed in a star shape on the outer side of the central axis of the prestressed clip group.

[0023] As the clamped steel strand is gradually tensioned, the relative force between the clamped steel strand and the prestressed clip group gradually increases. The anchor ring installed on the prestressed clip group guides the prestressed clip group. The prestressed clip group and the clamped steel strand generate the clamping force of the prestressed clip group on the clamped steel strand on the basis of the anchor ring applying support force to the prestress and the clamped steel strand releasing the stress generated by elastic deformation due to being tensioned. The clamping force of the prestressed clip group on the clamped steel strand gradually increases with the increase of the tensioning amplitude of the clamped steel strand. When the stress of the clamped steel strand due to elasticity reaches a preset range, each clip 1 has several stress releases. Grooves 7, so that several stress release grooves 7 in each clip 1 will deform or break. Furthermore, the width of each stress release groove 7 of this product near the inner cavity of the prestressed clip group gradually decreases as the stress release groove 7 gradually approaches the inner cavity of the prestressed clip group; thereby, after the stress generated by the elasticity of the clamped steel strand reaches a preset range, stress concentration occurs at the inner cavity of each stress release groove 7 near the inner cavity of the prestressed clip group, thereby achieving stress fracture of each clip 1 along the inner cavity of the several stress release grooves 7 near the prestressed clip group, so that each clip 1 breaks along the extension direction of the stress release groove 7, thereby increasing the clamping position of the clamped steel strand. The outer side of the circular tube portion of this product is provided with an O-ring mounting groove 8, and an O-ring 9 is provided in the O-ring mounting groove 8; installing the O-ring 9 facilitates limiting the relative positions of the multiple clips 1.

[0024] When the anchor ring used for the prestressed clip assembly is a multi-hole anchor ring, several strands must pass through the anchor holes of the multi-hole anchor ring one by one, causing some strands to deflect. As the tension on the strands increases, stress concentration is likely to occur at the junction of the strand clamping cavity 3 and the stress relief cavity 4 in the prestressed clip assembly due to the change in taper. Therefore, the strand passage cavity 2 and the strand clamping cavity 3 in this product are both cylindrical. The diameter of the strand passage cavity 2 is not less than that of the strand clamping cavity 3. A circular arc transition is used between the strand passage cavity 2 and the strand clamping cavity 3. The taper of the stress relief cavity 4 gradually increases as the stress relief cavity 4 moves away from the strand clamping cavity 3. This reduces the change in taper at the junction of the strand clamping cavity 3 and the stress relief cavity 4, thereby reducing the risk of strand breakage caused by stress concentration at the junction between the strand clamping cavity 3 and the stress relief cavity 4 and between the clamped strands.

[0025] Through this embodiment, in the process of gradually tensioning the steel strand, as the tensioning amplitude of the tensioned steel strand gradually increases, when the tensioning amplitude of the tensioned steel strand reaches a preset range, since a number of stress release grooves 7 are opened on each clip 1, each clip 1 is completely stressed or stress-broken under the action of the stress release groove 7, thereby increasing the effective clamping position of the clamped steel strand and reducing the phenomenon of too few effective clamping positions between the prestressed clip group and the clamped steel strand due to the difference between the diameter of the inner cavity of the prestressed clip group and the diameter of the circumscribed circle of the clamped steel strand; further, before the clamped steel strand is tensioned, the number of clips in the prestressed clip group remains consistent with the commercially available two-piece clip group or three-piece clip group, thereby not increasing the difficulty of the initial installation of the clips.

[0026] Example 2: Figures 1 to 6 As shown, an anchoring device includes a porous anchor ring 10. The porous anchor ring 10 includes an anchor ring body and several anchor holes formed in the anchor ring body. Each anchor hole is respectively installed with the prestressed clip group. A limit plate 11 is provided on one side of the porous anchor ring 10. The limit plate 11 on each side of the anchor hole is respectively provided with a steel strand passage hole 12. The limit plate 11 and the anchor ring body are provided with several threaded rods 13. Each threaded rod 13 on both sides of the limit plate 11 is respectively provided with a fastening nut 14. Furthermore, each threaded rod 13 is respectively provided with a groove 15, and a scale layer 16 is provided in the groove 15. The scale layer 16 extends in a direction from close to the porous anchor ring 10 to away from the porous anchor ring 10. The scale layer 16 is provided to facilitate feedback of the distance between the limit plate 11 and the porous anchor ring 10, thereby facilitating adjustment of the relative position of the limit plate 11 by using a plurality of fastening nuts 14, thereby enabling the limit plate 11 to reach a preset installation position.

[0027] The central axis of the limiting plate 11 and the central axis of the porous anchor ring 10 are coaxial. Several threaded rods 13 are evenly distributed in a star shape outside the central axis of the porous anchor ring 10. Each threaded rod 13 is threadedly connected to the anchor ring body. Each threaded rod 13 is provided with a locking nut 17, and several locking nuts 17 are fitted with the anchor ring body. This facilitates the use of the locking nuts 17 to further limit the position of the corresponding threaded rod 13.

[0028] The method of using this product is as follows: Figures 1 to 6As shown, the process includes the following steps: In a precast beam reserved channel, several steel strands are passed through the corrugated pipe in the precast beam reserved channel. The fixed ends of the strands are secured using anchoring devices. An anchor pad is then installed on the tensioned ends of the strands, so that the anchor pad and the pre-buried corrugated pipe in the precast beam channel abut against each other. The multi-porous anchor ring 10 of this product is then installed on the anchor pad. Several prestressed clip sets are then installed one-on-one in the anchor holes of the multi-porous anchor ring 10. Finally, the tensioned ends of the strands are passed one-on-one through the anchor holes of the multi-porous anchor ring 10 and the prestressed clip sets installed in the corresponding anchor holes of the multi-porous anchor ring 10. Then, the tensioning equipment is used to synchronously tension the tensioning ends of several steel strands. During the tensioning process, the prestressed clip group maintains relative sliding with the corresponding steel strands under the limiting action of the limiting plate 11. During the tensioning interval, the prestressed clip group retracts along with the corresponding steel strands under the action of the elastic force generated by the tensioning. Under the action of the porous anchor ring 10, the prestressed clip group gradually clamps the steel strands to prevent further retraction. The tensioning process and the tensioning interval process alternate until the several steel strands are tensioned.

[0029] By comparing Example 2 with Example 1, Example 2 provides an anchoring device applied to the prestressed clip group, which limits the relative position of the prestressed clip group during the tensioning process of the clamped steel strand by adjusting the relative position between the limit plate 11 and the porous anchor ring 10, thereby facilitating stable clamping of the clamped steel strand.

[0030] The embodiments described above are only preferred embodiments of the present invention and do not limit the scope of implementation of the present invention. Therefore, any equivalent changes or modifications made based on the structure, features and principles described in the patent scope of the present invention should be included in the scope of the patent application of the present invention.

Claims

1. A prestressed clip assembly, applied to a prestressed anchor, the prestressed clip assembly comprising a circular tubular structure composed of at least two clips (1), characterized in that: The circular tubular structure includes a circular tubular portion and a truncated cone portion, the outer diameter of the truncated cone portion gradually decreases in a direction from the circular tubular portion to the direction away from the circular tubular portion, the inner cavity of the prestressed clip group includes a steel strand passing cavity (2), a steel strand clamping cavity (3) and a stress release cavity (4) in sequence along the direction from the circular tubular portion to the truncated cone portion, a first internal thread (5) is provided in the steel strand clamping cavity (3), and a second internal thread (6) is provided in the stress release cavity (4), and each clip (1) is provided with a stress release groove (7) on the outer side, and the number of stress release grooves (7) is several, and the several stress release grooves (7) are evenly distributed in a star shape on the outer side of the central axis of the prestressed clip group.

2. The prestressed clip assembly according to claim 1, characterized in that: An O-ring installation groove (8) is provided on the outer side of the circular tube portion, and an O-ring (9) is provided in the O-ring installation groove (8).

3. The prestressed clip assembly according to claim 1, characterized in that: The steel strand passing cavity (2) and the steel strand clamping cavity (3) are both cylindrical, the diameter of the steel strand passing cavity (2) is not less than the diameter of the steel strand clamping cavity (3), an arc transition is adopted between the steel strand passing cavity (2) and the steel strand clamping cavity (3), and the taper of the stress release cavity (4) gradually increases as the stress release cavity (4) gradually moves away from the steel strand clamping cavity (3).

4. An anchoring device, characterized in that: The invention comprises a porous anchor ring (10), wherein the porous anchor ring (10) comprises an anchor ring body and a plurality of anchor holes opened on the anchor ring body, each of the anchor holes is respectively installed with a prestressed clip group according to any one of claims 1 to 3, a limiting plate (11) is provided on one side of the porous anchor ring (10), a steel strand passing hole (12) is respectively provided on the limiting plate (11) on one side of each anchor hole, a plurality of threaded rods (13) are provided on the limiting plate (11) and the anchor ring body, and a fastening nut (14) is respectively provided on each threaded rod (13) on both sides of the limiting plate (11).

5. The anchoring device according to claim 4, characterized in that: Each of the threaded rods (13) is provided with a groove (15), a scale layer (16) is provided in the groove (15), and the scale layer (16) extends in a direction from close to the porous anchor ring (10) to away from the porous anchor ring (10).

6. The anchoring device according to claim 4, characterized in that: The central axis of the limiting plate (11) and the central axis of the porous anchor ring (10) are located on the same axis, and a plurality of threaded rods (13) are evenly distributed in a star shape on the outside of the central axis of the porous anchor ring (10), each threaded rod (13) is threadedly connected to the anchor ring body, and each threaded rod (13) is respectively provided with a locking nut (17), and the plurality of locking nuts (17) are all fitted with the anchor ring body.

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