A prestressed anchoring structure for a pylon cable anchorage

Abstract

The utility model relates to a kind of bridge tower cable anchorage zone prestressed anchoring structure, bridge tower cable anchorage zone prestressed anchoring structure includes: bridge tower, prestressed steel strand, anchor pad and anchoring nut.Prestressed steel strand and anchor pad are located in bridge tower, anchor pad is located at the both ends of prestressed steel strand, and prestressed steel strand both ends are fixedly provided with extrusion sleeve, extrusion sleeve passes through anchor pad, extrusion sleeve is provided with external thread, anchoring nut sleeve is set on extrusion sleeve.Bridge tower is prefabricated with vertical main reinforcement and a pair of anchor groove, anchor groove is located between two vertical main reinforcement, and extrusion sleeve is located in anchor groove.The utility model is convenient for connecting device to be able to connect extrusion sleeve and tensioning equipment only by passing through anchor groove.Make the size of anchor groove can be set smaller, realize the anchor groove between two adjacent vertical main reinforcement and two adjacent hoop reinforcement, avoid the technical problem that vertical main reinforcement and hoop reinforcement outside tower wall need to avoid or disconnect.

Description

Technical Field

[0001] This utility model relates to the field of bridge construction, and in particular to a prestressed anchorage structure for the anchorage zone of a cable-stayed bridge tower. Background Technology

[0002] A cable-stayed bridge consists of a main girder, towers, stay cables, piers, and foundations. The main girder and towers are connected by stay cables, forming a combined structural system in which the main girder and towers are under compression and the stay cables are under tension. This system makes full use of the advantages of various materials and is one of the main structural forms of long-span bridges.

[0003] The connection area between the stay cable and the bridge tower is called the tower cable anchorage zone. Depending on the stress requirements, prestressed steel strands are generally installed within the tower wall. Currently, high-strength steel strands are mainly used for prestressing the tower wall in the cable anchorage zone, arranged in a grid or U-shape, using single-end or double-end tensioning methods, combined with low-retraction anchors to achieve effective prestressing of the tower wall. Existing technologies mainly have the following problems:

[0004] Prestressing requires slotting on the outside of the tower wall for anchoring. The vertical main bars and circumferential stirrups on the outside of the tower wall need to be avoided or broken, resulting in excessively large or discontinuous spacing between the vertical main bars and circumferential stirrups, forming weak points in the tower wall and posing a risk of cracking later. Utility Model Content

[0005] (a) Technical problems to be solved

[0006] This utility model provides a prestressed anchorage structure for the cable anchorage zone of a bridge tower, aiming to solve the technical problem in the prior art where, when prestressing is performed on the bridge tower and slots are cut on the tower, the vertical main reinforcement and circumferential stirrups on the outer side of the tower wall need to be avoided or broken, resulting in excessively large or discontinuous spacing between the vertical main reinforcement and circumferential stirrups.

[0007] (II) Technical Solution

[0008] To solve the above problems, this utility model provides a prestressed anchorage structure for the cable anchorage zone of a bridge tower, which includes: a bridge tower, prestressed steel strands, anchor plates, and anchor nuts.

[0009] The prestressed steel strand and the anchor plate are located inside the bridge tower. The anchor plate is located at both ends of the prestressed steel strand, and each end of the prestressed steel strand is fixedly provided with a compression sleeve. The compression sleeve passes through the anchor plate and is provided with external threads. The anchoring nut is sleeved on the compression sleeve.

[0010] The bridge tower is prefabricated with vertical main reinforcement bars and a pair of anchor grooves. The anchor grooves are located between the two vertical main reinforcement bars, and the extrusion sleeve is located inside the anchor grooves.

[0011] Preferably, the prestressed anchorage structure of the bridge tower cable anchorage zone further includes tensioning equipment and sleeve assembly;

[0012] The tensioning device is installed on the bridge tower and is located at one end of the anchor groove;

[0013] The sleeve assembly includes a tensioning connecting sleeve and a nut connecting sleeve. The nut connecting sleeve is sleeved on the tensioning connecting sleeve, and the nut connecting sleeve and the tensioning connecting sleeve can slide and rotate relative to each other. One end of the tensioning connecting sleeve is fixedly connected to the extrusion sleeve, and the other end of the tensioning connecting sleeve is fixedly connected to the tensioning device. One end of the nut connecting sleeve is sleeved on the anchoring nut, and the other end of the nut connecting sleeve is located outside the anchor groove. The nut connecting sleeve can drive the anchoring nut to rotate.

[0014] Preferably, one end of the tensioning sleeve is provided with an internal thread that mates with the external thread on the extrusion sleeve.

[0015] Preferably, the anchoring nut is a hexagonal nut, and one end of the nut connecting sleeve is provided with a connecting hole that matches the shape of the anchoring thread. The nut connecting sleeve is fitted onto the anchoring nut through the connecting hole.

[0016] Preferably, a corrugated pipe is provided inside the bridge tower, the prestressed steel strand is located inside the corrugated pipe, and a filler is provided inside the corrugated pipe.

[0017] Preferably, both ends of the corrugated pipe are fixedly connected to the anchor plate.

[0018] Preferably, the anchor plate is provided with a through hole, the extrusion sleeve can pass through the through hole, and there is a gap between the extrusion sleeve and the through hole.

[0019] Preferably, the anchor nut is fitted to the anchor plate.

[0020] Preferably, the tensioning device is a jack.

[0021] (III) Beneficial Effects

[0022] This invention involves fixing extrusion sleeves at both ends of a prestressed steel strand and machining external threads on the extrusion sleeves. When tensioning the prestressed steel strand, the connecting device only needs to pass through the anchor groove to connect the extrusion sleeve and the tensioning equipment. The connecting device can connect to the extrusion sleeve via a threaded connection to achieve tensioning of the prestressed steel strand. This allows the anchor groove on the bridge tower sidewall to be larger than the connecting device, thus enabling a smaller anchor groove size. This allows the anchor groove to be positioned between two adjacent vertical main reinforcement bars and two adjacent circumferential stirrups, avoiding the technical problem of excessively large or discontinuous spacing between the vertical main reinforcement bars and circumferential stirrups on the outer side of the tower wall, which would otherwise require avoidance or disconnection. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the plan layout of this utility model.

[0024] [Explanation of Markings in the Attached Images]

[0025] 1: Bridge tower; 10: Vertical main reinforcement; 11: Anchor groove; 12: Corrugated pipe; 2: Prestressed steel strand; 21: Extrusion sleeve; 3: Anchor plate; 4: Anchor nut; 5: Tensioning equipment; 61: Tensioning connecting sleeve; 62: Nut connecting sleeve. Detailed Implementation

[0026] To better explain and facilitate understanding of this utility model, the present utility model will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0027] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0028] Furthermore, in this utility model, the use of terms such as "first," "second," etc., is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0029] In this utility model, unless otherwise explicitly specified and limited, the terms "connection," "fixing," etc., should be interpreted broadly. For example, "fixing" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0030] This utility model provides a prestressed anchorage structure for the cable-anchored zone of a bridge tower 1. The prestressed anchorage structure includes: a bridge tower 1, prestressed steel strands 2, anchor plates 3, and anchor nuts 4. The prestressed steel strands 2 and anchor plates 3 are located inside the bridge tower 1. The anchor plates 3 are located at both ends of the prestressed steel strands 2, and each end of the prestressed steel strand 2 is fixedly equipped with a compression sleeve 21. The compression sleeve 21 passes through the anchor plate 3 and has external threads. The anchor nuts 4 are fitted onto the compression sleeves 21. The bridge tower 1 is prefabricated with vertical main reinforcement bars 10 and a pair of anchor grooves 11. The anchor grooves 11 are located between two adjacent vertical main reinforcement bars 10, and the compression sleeves 21 are located within the anchor grooves 11.

[0031] This application fixes extrusion sleeves 21 at both ends of the prestressed steel strand 2 and processes external threads on the extrusion sleeves 21. When tensioning the prestressed steel strand 2, the connecting device only needs to pass through the anchor groove 11 to connect the extrusion sleeve 21 and the tensioning device 5. The connecting device can connect to the extrusion sleeve 21 through a threaded connection to achieve tensioning of the prestressed steel strand 2. This means that the anchor groove 11 opened on the side wall of the bridge tower 1 only needs to be larger than the connecting device. Therefore, the size of the anchor groove 11 in this application can be set relatively small, realizing the placement of the anchor groove 11 between two adjacent vertical main reinforcements 10 and two adjacent circumferential stirrups. This avoids the technical problem that the vertical main reinforcements 10 and circumferential stirrups on the outer side of the tower wall need to be avoided or broken, resulting in excessively large or discontinuous spacing between the vertical main reinforcements 10 and circumferential stirrups. The small size of the anchor groove 11 does not conflict with the vertical main reinforcements 10 and circumferential stirrups of the tower wall in the cable anchor area, resulting in better stress performance of the tower wall and low risk of cracking. The on-site reinforcement work is minimal, which is beneficial for quality control. No holes need to be drilled in the outer formwork of bridge tower 1, allowing for the use of various types of formwork. Anchor groove 11 has small-sized round holes, minimizing the risk of cracking and falling concrete after sealing.

[0032] In a preferred embodiment, the connecting device can be in the form of a hollow rod with internal threads inside. The width of the anchor groove 11 only needs to be greater than the outer diameter of the hollow rod.

[0033] Furthermore, the prestressed anchorage structure of the cable-stayed zone of bridge tower 1 also includes a tensioning device 5 and a sleeve assembly. The tensioning device 5 is installed on bridge tower 1 and located at one end of the anchor groove 11. The sleeve assembly includes a tensioning connecting sleeve 61 and a nut connecting sleeve 62. The nut connecting sleeve 62 is fitted onto the tensioning connecting sleeve 61, and the nut connecting sleeve 62 and the tensioning connecting sleeve 61 can slide and rotate relative to each other. One end of the tensioning connecting sleeve 61 is fixedly connected to the compression sleeve 21, and the other end of the tensioning connecting sleeve 61 is fixedly connected to the tensioning device 5. One end of the nut connecting sleeve 62 is fitted onto the anchoring nut 4, and the other end of the nut connecting sleeve 62 is located outside the anchor groove 11. The nut connecting sleeve 62 can drive the anchoring nut 4 to rotate. In a preferred embodiment, the tensioning device 5 is a jack.

[0034] In the above scheme, the tensioning connecting sleeve 61 is connected to the extrusion sleeve 21 and then to the tensioning device 5. After the tensioning device 5 tensions the prestressed steel strand 2, the anchoring nut 4 is rotated by rotating the nut connecting sleeve 62, so that the anchoring nut 4 moves along the extrusion sleeve 21 and fits against the anchor plate 3, thus completing the tensioning. The nut connecting sleeve 62 is fitted on the tensioning connecting sleeve 61. The tensioning connecting sleeve 61 and the nut connecting sleeve 62 can rotate and slide relative to each other, which does not affect the tensioning of the prestressed steel strand 2 and the tightening of the anchoring nut 4. The width of the anchor groove 11 only needs to be greater than the outer diameter of the nut connecting sleeve 62. The tensioning connecting sleeve 61 and the nut connecting sleeve 62 are fitted together, which greatly reduces the width required for the anchor groove 11. This is more conducive to arranging the anchor groove 11 between two adjacent vertical main bars 10 and adjacent annular stirrups.

[0035] In a preferred embodiment, one end of the tensioning sleeve is provided with an internal thread that mates with the external thread on the compression sleeve 21. After the tensioning sleeve is inserted into the anchor groove 11, it is only necessary to align it with the compression sleeve 21 and then rotate the tensioning sleeve to achieve the connection between the tensioning sleeve and the compression sleeve 21, which is a simple connection method. The anchoring nut 4 is a hexagonal nut, and one end of the nut connecting sleeve 62 is provided with a connecting hole that matches the shape of the anchoring thread. The nut connecting sleeve 62 is sleeved on the anchoring nut 4 through the connecting hole. After the nut connecting sleeve 62 is inserted into the anchor groove 11, the action of rotating the anchoring nut 4 can be achieved by sleeved one end of the nut connecting sleeve 62 onto the anchoring nut 4.

[0036] Furthermore, a corrugated pipe 12 is installed inside the bridge tower 1, and the prestressed steel strand 2 is located inside the corrugated pipe 12, which is also filled with a filler. The filler can be added or not depending on the design requirements, and the filler is a slow-bonding material that does not affect the free expansion and contraction of the steel strand and the extrusion sleeve 21.

[0037] Furthermore, both ends of the corrugated pipe 12 are fixedly connected to the anchor plate 3. The anchor plate 3 is provided with a through hole, through which the compression sleeve 21 can pass, and there is a gap between the compression sleeve 21 and the through hole. The anchor nut 4 is fitted into the anchor plate 3.

[0038] In conclusion, the specific technical approach of this application is as follows:

[0039] The prestressed steel strand 2 uses high-strength steel strands with a nominal diameter of 15.2mm or 21.6mm, and is constructed using the post-tensioning method. The ends of the prestressed steel strand 2 are anchored using extrusion sleeves 21. The extrusion sleeves 21 are extruded and then threaded. Tensioning is achieved by connecting the extrusion sleeves 21 and jacks via tensioning connecting sleeves 61, thus reducing the size of the anchor groove 11. Anchor plates 3 are installed at the ends of the prestressed steel strand 2 as force transmission structures. The prestress is transferred to the anchor plates 3 and the tower wall through the extrusion sleeves 21 and anchoring nuts 4. The anchoring nuts 4 are tightened via nut connecting sleeves 62.

[0040] To illustrate the technical solution of the present invention, further explanation is provided in conjunction with embodiments.

[0041] Taking the cable-stayed bridge tower 1's cable-anchorage area as an example. The prestressed steel strand 2 uses a single strand with a nominal diameter of 15.2mm and a tensile strength standard value of 1860MPa. The corresponding outer diameter of the extrusion sleeve 21 is 30mm (after extrusion). The anchoring nut 4 uses a hexagonal head nut with an outer diameter of 50mm. The outer sleeve 6 has an inner diameter of 60mm and an outer diameter of 61mm. The vertical main reinforcement 10 of the tower wall of tower 1 uses HRB400 steel bars with a diameter of 28mm, a spacing of 125mm, and a clear spacing of 65mm. The horizontal circumferential stirrups of the tower wall use HRB400 steel bars with a diameter of 20mm, a spacing of 125mm, and a clear spacing of 81mm. The outer diameter of the anchor groove 11 is smaller than the clear spacing of the vertical and horizontal reinforcement bars, allowing for direct installation, tensioning, and anchoring using the gaps between the reinforcement bars.

[0042] The implementation steps of the plan are as follows:

[0043] 1. Determine the working length of the prestressed steel strand 2 based on the tower wall dimensions of bridge tower 1, and cut the material according to the working length.

[0044] 2. The two ends of the steel strand are anchored by extrusion sleeve 21. The extrusion sleeve 21 is then threaded after being extruded.

[0045] 3. Install anchor plate 3 and corrugated pipe 12, and fill corrugated pipe 12 with a slow adhesive.

[0046] 4. On-site installation of prestressed and anchoring structures.

[0047] 5. Install the jack and tensioning connecting sleeve 61, and tension the prestressed steel strand 2; install the nut connecting sleeve 62, and use a torque wrench to turn the nut connecting sleeve 62 and tighten the anchor nut 4.

[0048] 6. Remove the nut connecting sleeve 62 and the tension connecting sleeve 61, and remove the jack.

[0049] 7. Seal the anchor groove 11 and apply waterproof coating.

[0050] It should be understood that the above description of the specific embodiments of this utility model is only for illustrating the technical route and features of this utility model, and its purpose is to enable those skilled in the art to understand the content of this utility model and implement it accordingly. However, this utility model is not limited to the specific embodiments described above. All changes or modifications made within the scope of the claims of this utility model should be covered by the protection scope of this utility model.

Claims

1. A prestressed anchorage structure for the cable anchorage zone of a bridge tower, characterized in that, The prestressed anchorage structure of the bridge tower cable anchorage area includes: bridge tower (1), prestressed steel strand (2), anchor plate (3), and anchor nut (4); The prestressed steel strand (2) and the anchor plate (3) are located inside the bridge tower (1). The anchor plate (3) is located at both ends of the prestressed steel strand (2). Both ends of the prestressed steel strand (2) are fixedly provided with compression sleeves (21). The compression sleeves (21) pass through the anchor plate (3). The compression sleeves (21) are provided with external threads. The anchoring nut (4) is sleeved on the compression sleeves (21). The bridge tower (1) is prefabricated with vertical main reinforcement (10) and at least one pair of anchor grooves (11), the anchor grooves (11) being located between the two vertical main reinforcements (10), and the extrusion sleeve (21) being located within the anchor grooves (11).

2. The prestressed anchorage structure for the cable anchorage zone of the bridge tower as described in claim 1, characterized in that, The prestressed anchorage structure of the bridge tower cable anchorage area also includes tensioning equipment (5) and sleeve assembly; The tensioning device (5) is installed on the bridge tower (1), and the tensioning device (5) is located at one end of the anchor groove (11); The sleeve assembly includes a tensioning connecting sleeve (61) and a nut connecting sleeve (62). The nut connecting sleeve (62) is sleeved on the tensioning connecting sleeve (61). The nut connecting sleeve (62) and the tensioning connecting sleeve (61) can slide and rotate relative to each other. One end of the tensioning connecting sleeve (61) is fixedly connected to the extrusion sleeve (21), and the other end of the tensioning connecting sleeve (61) is fixedly connected to the tensioning device (5). One end of the nut connecting sleeve (62) is sleeved on the anchoring nut (4), and the other end of the nut connecting sleeve (62) is located outside the anchor groove (11). The nut connecting sleeve (62) can drive the anchoring nut (4) to rotate.

3. The prestressed anchorage structure for the cable anchorage zone of the bridge tower as described in claim 2, characterized in that, One end of the tensioning connecting sleeve (61) is provided with an internal thread that matches the external thread on the extrusion sleeve (21).

4. The prestressed anchorage structure for the cable anchorage zone of the bridge tower as described in claim 3, characterized in that, The anchoring nut (4) is a hexagonal nut, and one end of the nut connecting sleeve (62) is provided with a connecting hole that matches the shape of the anchoring thread. The nut connecting sleeve (62) is sleeved on the anchoring nut (4) through the connecting hole.

5. The prestressed anchorage structure for the cable anchorage zone of the bridge tower as described in any one of claims 1-4, characterized in that, The bridge tower (1) is provided with a corrugated pipe (12), the prestressed steel strand (2) is located inside the corrugated pipe (12), and the corrugated pipe (12) is provided with a filler.

6. The prestressed anchorage structure for the cable anchorage zone of the bridge tower as described in claim 5, characterized in that, Both ends of the corrugated pipe (12) are fixedly connected to the anchor plate (3).

7. The prestressed anchorage structure for the cable anchorage zone of the bridge tower as described in any one of claims 1-4, characterized in that, The anchor plate (3) is provided with a through hole, the extrusion sleeve (21) can pass through the through hole, and there is a gap between the extrusion sleeve (21) and the through hole.

8. The prestressed anchorage structure for the cable anchorage zone of the bridge tower as described in any one of claims 1-4, characterized in that, The anchor nut (4) is attached to the anchor plate (3).

9. The prestressed anchorage structure for the cable anchorage zone of the bridge tower as described in any one of claims 2-4, characterized in that, The tensioning device (5) is a jack.

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