Prestressed tendon composite clamping and anchoring structure

Abstract

The invention relates to the technical field of components used in prestressed structures, in particular to a prestressed tendon composite clamping and anchoring structure. According to the combined type pre-stressed tendon anchoring device, the extrusion sleeve is arranged at the end, exceeding the wedge-shaped clamping piece, of the pre-stressed tendon, extrusion bond-wrapping anchoring is achieved while wedge-caulking anchoring is achieved, meanwhile, the extrusion sleeve is in pressing fit with the large end of the wedge-shaped clamping piece, namely, the extrusion sleeve tightly presses the wedge-shaped clamping piece in the stress direction of the pre-stressed tendon, and the wedge-shaped clamping piece is tightly clamped; after the extrusion sleeve compresses the wedge-shaped clamping piece, the extrusion sleeve and the wedge-shaped clamping piece cooperate to form a whole relatively fixed in the axial direction of the prestressed tendon, and a wedge-tight holding and wrapping composite anchoring body is formed at the end of the prestressed tendon. The wedged holding composite anchoring body can be integrally pushed into the taper hole to achieve integral anchoring, and the anchoring effect is reliable.

Description

Technical Field

[0001] The invention relates to the technical field of components used in prestressed structures, in particular to a prestressed tendon composite clamping and anchoring structure. Background Art

[0002] Prestressed anchors are a type of building reinforcement commonly used in infrastructure construction, and the reliability of their anchoring has a very important impact on their support capacity. For example, the anchor disclosed in the Chinese utility model patent with authorization announcement number CN200952401Y includes a tray, i.e., an anchor pad, an anchor ring, and a steel strand, wherein the anchor ring is provided with a conical hole, the outer end of the steel strand passes through the conical hole, and a wedge-shaped clip that holds the steel strand is installed in the conical hole. When the steel strand is subjected to inward force, the wedge-shaped clip is wedged in the conical hole, and the greater the force, the more obvious the wedging effect, thereby achieving an anchoring effect. However, this traditional anchoring method, when applied to prestressed structures such as slings, cables, suspenders, tie rods, suspension anchors, pressure vessels, etc. that are subjected to alternating stress with a large vertical amplitude, has the risk of the wedge clip exiting the conical hole, resulting in anchor failure. Summary of the Invention

[0003] The purpose of the present invention is to provide a composite clamping and anchoring structure for prestressed tendons to solve the problem that the existing anchoring is achieved by combining a wedge-shaped clip and a tapered hole. Under the condition of alternating force with large amplitude, the wedge-shaped clip has the risk of pushing out the tapered hole and causing anchoring failure.

[0004] The prestressed tendon composite clamping and anchoring structure of the present invention includes an anchor plate and an anchor ring. The anchor ring is provided with a tapered hole. The anchor plate is provided with an avoidance channel corresponding to the tapered hole for allowing the prestressed tendon to pass through. The end of the prestressed tendon passes through the avoidance channel and the tapered hole from the inside to the outside. The tapered hole is equipped with a group of wedge-shaped clips that cooperate with it and are used to wedge the prestressed tendon. The outer end of the prestressed tendon extends beyond the wedge-shaped clip and is provided with an extrusion sleeve to achieve gripping anchoring. The extrusion sleeve is pressed against the end of the group of wedge-shaped clips toward the inner side of the tapered hole and cooperates with the group of wedge-shaped clips to form a wedge-tightening and gripping composite anchoring body.

[0005] Furthermore, the large end of the wedge-shaped clip protrudes from the tapered hole so that the extrusion sleeve presses the large end of the wedge-shaped clip on the outside of the tapered hole.

[0006] Furthermore, the outer diameter of the extrusion sleeve is not larger than the inner diameter of the large diameter end of the tapered hole and is not smaller than the inner diameter of the small diameter end of the tapered hole.

[0007] Furthermore, the outer diameter of the extrusion sleeve is not less than half of the outer diameter of the large end of the wedge-shaped clip.

[0008] Furthermore, the end surface of the extrusion sleeve facing the wedge-shaped clip is an annular plane.

[0009] Furthermore, the length of the extrusion sleeve is comparable to the length of the wedge-shaped clip.

[0010] Furthermore, the prestressed tendons are steel strands or steel bars.

[0011] Furthermore, the set of wedge-shaped clips includes two wedge-shaped clips in a pair.

[0012] The present invention is a combined invention, which realizes extrusion and gripping anchoring while realizing wedge-tightening anchoring by arranging an extrusion sleeve at the end of the prestressed tendon that extends beyond the wedge-shaped clip. At the same time, the extrusion sleeve is pressed and matched with the large end of the wedge-shaped clip, that is, the extrusion sleeve presses the wedge-shaped clip in the force direction of the prestressed tendon, which can further improve the wedging effect. Moreover, after the extrusion sleeve presses the wedge-shaped clip, the two cooperate to form a relatively fixed whole in the axial direction of the prestressed tendon, and a wedge-tightening composite anchor body is formed at the end of the prestressed tendon. When the prestressed tendon reaches the set tension, the wedge-tightening composite anchor body can be pushed into the tapered hole as a whole to realize overall anchoring, and the anchoring effect is more reliable.

[0013] Compared with the existing methods of using wedge-tight anchoring or extrusion-grip anchoring separately, this solution combines wedge-tight anchoring and extrusion-grip composite anchoring. The cooperation between the two not only realizes simultaneous anchoring of two methods, but also enhances the wedge-tight anchoring effect, forming a larger anchor body at the end of the prestressed tendon, which can ensure better anchoring reliability when the prestressed tendon is subjected to alternating forces. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a schematic structural diagram of an embodiment of the prestressed tendon composite clamping and anchoring structure of the present invention when in use.

[0015] In the figure: 1. Anchor plate; 2. Anchor ring; 3. Wedge clip; 4. Extrusion sleeve; 5. Steel strand; 6. Support member; 7. Avoidance passage. DETAILED DESCRIPTION

[0016] The present invention aims to solve the problem that the prestressed tendons in the existing prestressed anchors use wedge-shaped clips for wedge-tight anchoring. However, when used in alternating force conditions with large amplitude, there is a risk that the wedge-tight clip will withdraw due to the lack of self-locking ability between the wedge-shaped clip and the tapered hole, which may lead to failure of the wedge-tight anchoring. By adding an extrusion grip anchoring on the basis of the wedge-tight anchoring, and pressing the extrusion sleeve against the end of the wedge-tight anchoring, the wedge-tight anchoring and the extrusion grip anchoring cooperate with each other to form a wedge-tight grip composite anchor body at the end of the steel strand, which can ensure better anchoring reliability under the condition that the prestressed tendons are subjected to alternating forces.

[0017] Based on the above concept, the implementation method of the prestressed tendon composite clamping and anchoring structure of the present invention is as follows: like Figure 1As shown, the composite clamping and anchoring structure of the prestressed tendon of the present invention includes an anchor plate and an anchor ring. The anchor plate is fitted with the supported component and is used to bear the anchoring preload. The anchor ring is installed on the side of the anchor plate that is away from the supported component, that is, the outside. A tapered hole is provided on the anchor ring, and an avoidance channel corresponding to the tapered hole is provided on the anchor plate for allowing the prestressed tendon to pass through. The end of the prestressed tendon passes through the avoidance channel and the tapered hole from the inside to the outside. A group of wedge-shaped clips that match the tapered surface of the tapered hole are installed in the tapered hole. The group of wedge-shaped clips are two pairs of wedge-shaped clips that are symmetrically buckled on the outside of the prestressed tendon, or they can be three wedge-shaped clips that surround the outside of the prestressed tendon. The outer end of the prestressed tendon extends out of the tapered hole and exceeds the wedge clip. The outer end of the prestressed tendon is provided with an extrusion sleeve to achieve extrusion, gripping and anchoring.

[0018] Based on such a structure, the extrusion sleeve forms an extrusion grip anchor at the outer end of the prestressed tendon. Under the tensile force of the prestressed tendon, the extrusion sleeve moves inward and pushes the group of wedge clips to move, and then pushes the group of wedge clips into the tapered hole, and the inner side surfaces of the group of wedge clips contact the prestressed tendon; as the thrust of the extrusion sleeve on the wedge clips increases, the inward end surface of the extrusion sleeve and the outer end surface of the group of wedge clips fit together and press tightly, and at this time, the extrusion sleeve and the group of wedge clips become a whole that will not move relative to each other in the axial direction of the prestressed tendon; as the tensile force of the prestressed tendon further increases, under the thrust of the extrusion sleeve, the wedge clips radially clamp the prestressed tendon under the action of the tapered surface of the tapered hole, thereby realizing wedge-tight anchoring, that is, the group of wedge clips and the extrusion sleeve form a wedge-tight grip composite anchor body at the outer end of the prestressed tendon. As the tension of the prestressed tendons gradually increases and reaches the expected tension of the prestressed tendons, the amount of advancement of the wedge-shaped clip by the extrusion sleeve reaches the set maximum value, thereby achieving permanent, safe and reliable anchoring of the prestressed tendons. That is, the anchoring structure of the present invention achieves self-propelled anchoring.

[0019] The greater the force on the prestressed tendons of the anchoring structure of the present invention, the more obvious the pushing effect of the extrusion sleeve on the wedge-shaped clip is, and the more obvious the wedging effect of the wedge-shaped clip on the prestressed tendons is. Therefore, even when applied to alternating force conditions with large amplitude, the risk of anchor failure caused by the withdrawal of the wedge-shaped clip is avoided due to the pressing effect of the extrusion sleeve on the wedge-shaped clip.

[0020] More specifically, the large end of the wedge-shaped clip protrudes from the tapered hole, allowing the extrusion sleeve to press the large end of the wedge-shaped clip against the outside of the tapered hole. This allows for a certain amount of spacing between the extrusion sleeve and the tapered hole, even when subjected to large-amplitude alternating forces during use. This prevents the extrusion sleeve from being interfered with by the tapered hole and unable to advance and press against the wedge-shaped clip, thus ensuring that the extrusion sleeve is always pressed against the end of the wedge-shaped clip. Furthermore, the outer diameter of the extrusion sleeve is no larger than the inner diameter of the large-diameter end of the tapered hole and no smaller than the inner diameter of the small-diameter end of the tapered hole. This arrangement allows the extrusion sleeve to move inward with the prestressed tendon to a greater axial distance until it contacts the inner wall of the tapered hole, making it less likely to interfere with the tapered hole.

[0021] To achieve a more reliable pushing effect on the wedge-shaped clip, the outer diameter of the compression sleeve is no less than half the outer diameter of the large end of the wedge-shaped clip. The outer diameter of the compression sleeve can be equal to half the outer diameter of the large end of the wedge-shaped clip, or greater than half the outer diameter of the large end of the wedge-shaped clip, or directly equal to the outer diameter of the large end of the wedge-shaped clip. Of course, in other embodiments, the outer diameter of the compression sleeve is greater than the outer diameter of the large end of the wedge-shaped clip, and it is also feasible to apply a compressive pushing effect to the large end of the wedge-shaped clip from the entire end surface of the wedge-shaped clip.

[0022] The compression sleeve is a conventional, commonly used compression anchor sleeve. Its end surface facing the wedge-shaped clip is an annular flat surface. This allows for axial thrust to be applied to the wedge-shaped clip. Combined with the inner conical surface of the tapered hole, this ensures that the wedge-shaped clip remains radially close to the prestressed tendon during axial movement. Of course, in some embodiments, the end surface of the compression sleeve facing the wedge-shaped clip can also be a conical surface to facilitate radial convergence of the wedge-shaped clip when the wedge-shaped clip is pushed.

[0023] When selecting the extrusion sleeve, in order to ensure the reliability of the extrusion grip anchoring and the reliable propulsion and compression of the wedge-shaped clip, the length of the extrusion sleeve should not be too short. However, considering that the wedge-tightening anchoring and the grip anchoring do not occupy a large axial space when used in combination, the length of the extrusion sleeve should not be too long. Therefore, in this embodiment, the length of the extrusion sleeve is equivalent to the length of the wedge-shaped clip, for example, the two are equal, or the extrusion sleeve is slightly longer than the wedge-shaped clip, or the wedge-shaped clip is slightly longer than the extrusion sleeve.

[0024] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. The scope of patent protection of the present invention shall be based on the claims. Any equivalent structural changes made using the description and drawings of the present invention shall be included in the scope of protection of the present invention.

Claims

1. A composite clamping and anchoring structure for prestressed tendons, characterized in that: It includes an anchor plate and an anchor ring. The anchor ring is provided with a tapered hole. The anchor plate is provided with an avoidance channel corresponding to the tapered hole for allowing the prestressed tendons to pass through. The ends of the prestressed tendons pass through the avoidance channel and the tapered hole from the inside to the outside. The tapered hole is equipped with a group of wedge-shaped clips that cooperate with it and are used to wedge the prestressed tendons. The outer ends of the prestressed tendons extend beyond the wedge-shaped clips and are provided with extrusion sleeves to achieve gripping and anchoring. The extrusion sleeves are pressed against the ends of the group of wedge-shaped clips toward the inner side of the tapered hole and cooperate with the group of wedge-shaped clips to form a wedge-tightening and gripping composite anchor body.

2. The prestressed tendon composite clamping and anchoring structure according to claim 1 is characterized in that: The large end of the wedge-shaped clip protrudes from the tapered hole so that the extrusion sleeve presses the large end of the wedge-shaped clip on the outer side of the tapered hole.

3. The prestressed tendon composite clamping and anchoring structure according to claim 2 is characterized in that: The outer diameter of the extrusion sleeve is not larger than the inner diameter of the large diameter end of the tapered hole and is not smaller than the inner diameter of the small diameter end of the tapered hole.

4. The prestressed tendon composite clamping and anchoring structure according to claim 2 is characterized in that: The outer diameter of the extrusion sleeve shall not be less than half of the outer diameter of the large end of the wedge-shaped clip.

5. The prestressed tendon composite clamping and anchoring structure according to any one of claims 1 to 4, characterized in that: The end surface of the extrusion sleeve facing the wedge-shaped clip is an annular plane.

6. The prestressed tendon composite clamping and anchoring structure according to any one of claims 1 to 4, characterized in that: The length of the extrusion sleeve is equivalent to the length of the wedge clip.

7. The prestressed tendon composite clamping and anchoring structure according to any one of claims 1 to 4, characterized in that: Prestressed tendons are steel strands or steel bars.

8. The prestressed tendon composite clamping and anchoring structure according to any one of claims 1 to 4, characterized in that: The set of wedge clips includes two wedge clips in a pair.

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