Prestressed anchoring structure of cable-stayed bridge cable tower anchoring area

Abstract

The utility model relates to a prestressed anchoring structure for a cable tower anchoring area of a cable-stayed bridge. The prestressed anchoring structure for the cable tower anchoring area of the cable-stayed bridge comprises a steel reinforcement framework, a plurality of pairs of steel notches and a prestressed pipeline. The steel reinforcement framework comprises a plurality of vertical main reinforcements and a plurality of annular stirrups, the steel notches are formed in the side wall of the steel reinforcement framework, and the vertical main reinforcements and the annular stirrups at the steel notches in the steel reinforcement framework are fixedly connected with the steel notches. A prestressed pipeline is connected with the two paired steel notches, and the prestressed pipeline is used for containing prestressed steel beams. After the vertical main reinforcements or the annular stirrups in the steel reinforcement framework are disconnected at the position of the steel notch, the vertical main reinforcements or the annular stirrups are welded with the anchoring reinforcements at the steel notch, a closed steel reinforcement framework can be formed, and the reinforcements at the prestressed anchoring position are continuous and reliable in force transmission. The bridge tower outer formwork does not need to be perforated and can be matched with various types of formworks.

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] Cable-stayed bridges consist of beams, towers, cables, piers, and foundations. They connect the main beams and towers via stay cables, forming a combined structural system where the main beams and towers are under compression, and the stay cables are under tension. This is one of the main structural forms of long-span bridges. The connection between the stay cables and the main beams and towers is a key load-bearing component of a cable-stayed bridge. A straightforward approach to anchoring the stay cables to the towers is to use hollow concrete tower columns, anchoring the stay cables inside the columns. Since the invention of modern cable-stayed bridges, this method has been the mainstream tower anchoring approach, leading to three main types of tower anchoring: prestressed anchoring, steel anchor boxes, and steel anchor beams. Prestressed anchoring refers to directly applying prestress to the tower wall to resist the tension of the stay cables. While steel anchor boxes and steel anchor beams do not rely primarily on the tower wall as a load-bearing component, sufficient prestress is still required in the tower wall to accommodate coordinated stress and situations such as cable breakage or replacement. Previously, the slots on the outer side of the tower wall had to be reserved through the outer formwork, and the vertical main reinforcement and circumferential stirrups had to be avoided or disconnected at the slots. Utility Model Content

[0003] (a) Technical problems to be solved

[0004] This utility model provides a prestressed anchorage structure for the anchorage zone of a cable-stayed bridge tower, aiming to solve the technical problem in the prior art where the vertical main reinforcement and circumferential stirrups must be avoided or broken at the slot, resulting in a broken steel reinforcement cage and unreliable force transmission.

[0005] (II) Technical Solution

[0006] To solve the above problems, this utility model provides a prestressed anchorage structure for the anchorage zone of a cable-stayed bridge tower, which includes: a steel reinforcement cage, multiple pairs of steel slots, and prestressed ducts.

[0007] The steel reinforcement cage includes multiple vertical main bars and multiple circumferential stirrups. The steel groove is installed on the side wall of the steel reinforcement cage, and the vertical main bars and the circumferential stirrups at the steel groove on the steel reinforcement cage are fixedly connected to the steel groove.

[0008] One of the prestressed ducts connects to two pairs of steel slots, and the prestressed duct is used to accommodate prestressed steel strands.

[0009] Preferably, the steel channel includes: an end sealing plate and a cylindrical body;

[0010] Both ends of the cylinder are provided with openings. The cylinder is fixedly mounted on the end sealing plate, and the end sealing plate is located at the opening at the first end of the cylinder. The area of ​​the opening at the first end of the cylinder is smaller than the area of ​​the opening at the second end of the cylinder. The opening at the second end of the cylinder is flush with the side of the steel reinforcement frame.

[0011] The end cap plate is fixedly connected to the end of the prestressed duct, and the vertical main reinforcement and the circumferential stirrup are both fixed to the cylinder.

[0012] Preferably, the cylinder includes four side plates connected end to end in sequence, the end sealing plate is a rectangular plate, and one side plate is provided on each of the four sides of the end sealing plate.

[0013] Preferably, the end sealing plate is a circular plate, and the cylindrical body is frustoconical in shape.

[0014] Preferably, the end cap plate has a through hole communicating with the prestressed duct.

[0015] Preferably, the end cap is perpendicular to the prestressed duct.

[0016] Preferably, one end of the vertical main reinforcement and the circumferential stirrup at the steel groove on the steel reinforcement cage are both fitted to the cylinder body.

[0017] Preferably, one end of the vertical main reinforcement and one end of the circumferential stirrup at the steel groove on the steel reinforcement cage are fixedly connected to the cylinder.

[0018] (III) Beneficial Effects

[0019] In this utility model, the vertical main bars or circumferential stirrups in the steel reinforcement cage are broken at the steel channel opening and then welded to the anchoring bars at the steel channel opening to form a closed steel reinforcement cage. The reinforcement at the prestressed anchoring position is continuous, ensuring reliable force transmission. No holes are required for the bridge tower external formwork, making it compatible with various types of formwork. Attached Figure Description

[0020] Figure 1 This is a partial assembly diagram of the steel reinforcement cage, multiple pairs of steel grooves, and prestressed ducts in this utility model;

[0021] Figure 2 This is a schematic diagram of the assembly of the steel groove with the vertical main reinforcement and the circumferential stirrups in this utility model.

[0022] [Explanation of Labels in the Attached Image]

[0023] 10: Reinforcing steel cage; 11: Vertical main reinforcement; 12: Circumferential stirrups;

[0024] 20: Steel channel opening; 21: End sealing plate; 22: Cylinder body;

[0025] 30: Prestressed duct. 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 anchorage zone of a cable-stayed bridge tower. The prestressed anchorage structure includes: a reinforcing steel cage 10, multiple pairs of steel grooves 20, and prestressing ducts 30. The reinforcing steel cage 10 includes multiple vertical main bars 11 and multiple circumferential stirrups 12. The steel grooves 20 are installed on the sidewalls of the reinforcing steel cage 10, and the vertical main bars 11 and circumferential stirrups 12 at the steel grooves 20 are fixedly connected to the steel grooves 20. A prestressing duct 30 connects two pairs of steel grooves 20, and the prestressing duct 30 is used to accommodate prestressed steel strands.

[0031] The technical approach in this application is to reserve slots in the tower wall by embedding prefabricated permanent steel slots 20 within the outer formwork of the bridge tower without altering its external formwork. These slots are then sealed after the prestressed steel strands are tensioned and anchored. The vertical main bars 11 or circumferential stirrups 12 in the steel reinforcement cage 10 are disconnected at the steel slot 20 location and then welded to the anchoring reinforcement of the steel slot 20, forming a closed steel reinforcement cage. This ensures continuous reinforcement at the prestressed anchorage location and reliable force transmission. Compared to traditional anchorage methods, this reduces extensive interference between the bridge tower reinforcement and the prestressed anchorage structure, lowers construction difficulty, and improves construction quality. The bridge tower external formwork requires no openings and can be matched with various types of formwork.

[0032] Further, the steel channel 20 includes an end-sealing plate 21 and a cylindrical body 22. Both ends of the cylindrical body 22 have openings. The cylindrical body 22 is fixedly mounted on the end-sealing plate 21, with the end-sealing plate 21 located at the opening at the first end of the cylindrical body 22. The area of ​​the opening at the first end of the cylindrical body 22 is smaller than the area of ​​the opening at the second end of the cylindrical body 22. The opening at the second end of the cylindrical body 22 is flush with the side of the reinforcing cage 10. The end-sealing plate 21 is fixedly connected to the end of the prestressed duct 30, and the vertical main reinforcement 11 and the circumferential stirrups 12 are both fixed to the cylindrical body 22. In this application, the vertical main reinforcement 11 and the circumferential stirrups on the reinforcing cage 10 at the opening at the second end of the cylindrical body 22 are both disconnected, and both ends of the disconnected sections are fixedly mounted to the cylindrical body 22.

[0033] In one embodiment, the cylinder 22 includes four side plates connected end to end in sequence, and the overall shape of the cylinder 22 is frustum-shaped. The end sealing plate 21 is a rectangular plate, and a side plate is provided on each of the four sides of the end sealing plate 21. In another embodiment, the end sealing plate 21 is a circular plate, and the shape of the cylinder 22 is frustum-shaped.

[0034] Furthermore, the end cap 21 has a through hole that communicates with the prestressed duct 30. The end cap 21 is perpendicular to the prestressed duct 30.

[0035] Finally, one end of the vertical main reinforcement 11 and the circumferential stirrup 12 at the steel channel opening 20 on the reinforcing steel cage 10 are both fitted to the cylinder 22. One end of the vertical main reinforcement 11 and the circumferential stirrup 12 at the steel channel opening 20 on the reinforcing steel cage 10 are fixedly connected to the cylinder 22 (specifically, by welding).

[0036] In an embodiment of this utility model, the cable anchorage area of ​​a cable-stayed bridge tower is taken as an example. The prestressed steel strands are single steel strands with a nominal diameter of 15.2 mm and a tensile strength standard value of 1860 MPa. The depth of the steel groove 20 is 20 cm, the end cap 21 has a planar dimension of 30 cm × 30 cm (with a φ11 cm hole), the thickness of the end cap 21 is 5 cm, and the slope of the surrounding plate opening is 1:1.5. The vertical main reinforcement 11 of the tower wall uses HRB400 steel bars with a diameter of 28 mm, a spacing of 125 mm, and a clear spacing of 65 mm; the horizontal circumferential stirrups 12 of the tower wall use HRB400 steel bars with a diameter of 20 mm, a spacing of 125 mm, and a clear spacing of 81 mm.

[0037] The implementation steps of the plan are as follows:

[0038] 1. Based on the location and specifications of the prestressed steel strands in the bridge tower, process the steel grooves 20 at each location of the bridge tower and weld the anchor bars to form a steel reinforcement skeleton 10.

[0039] 2. Erect formwork for the bridge tower and tie the reinforcing bars; embed steel grooves 20mm in the tower wall.

[0040] 3. The vertical main reinforcement 11 and circumferential stirrup 12 on the outer side of the tower wall are welded to the anchor reinforcement of the steel channel 20 at the position of the steel channel 20 to form a closed reinforcement skeleton.

[0041] 4. After the bridge tower concrete is poured, the prestressed steel strands are tensioned and anchored, and 20 mm of concrete is poured into the steel channel opening to seal the anchor.

[0042] 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 anchoring structure for a cable-stayed bridge tower anchorage zone, characterized by, The prestress anchoring structure of the cable-stayed bridge tower anchorage area comprises a steel reinforcement framework (10), a plurality of pairs of steel notches (20) and prestress pipes (30); The steel reinforcement framework (10) comprises a plurality of vertical main reinforcements (11) and a plurality of hoop stirrups (12), the steel notches (20) are installed on the side walls of the steel reinforcement framework (10), and the vertical main reinforcements (11) and the hoop stirrups (12) at the steel notches (20) on the steel reinforcement framework (10) are fixedly connected with the steel notches (20); One prestress pipe (30) is connected to two steel notches (20) in a pair, and the prestress pipe (30) is used for accommodating a prestress steel strand.

2. The prestressed anchorage structure for the anchorage zone of a cable tower of a cable-stayed bridge according to claim 1, wherein The steel notch (20) comprises an end sealing plate (21) and a cylinder (22); Both ends of the cylinder (22) are provided with openings, the cylinder (22) is fixedly arranged on the end sealing plate (21), the end sealing plate (21) is located at the opening of the first end of the cylinder (22), the area of the opening of the first end of the cylinder (22) is smaller than the area of the opening of the second end of the cylinder (22), and the opening of the second end of the cylinder (22) is flush with the side surface of the steel reinforcement framework (10); The end sealing plate (21) is fixedly connected with the end of the prestress pipe (30), and the vertical main reinforcements (11) and the hoop stirrups (12) are fixedly arranged on the cylinder (22).

3. The prestressed anchorage structure for the anchorage zone of a cable tower of a cable-stayed bridge according to claim 2, wherein The cylinder (22) comprises four enclosing plates connected in sequence, the end sealing plate (21) is a rectangular plate, and one enclosing plate is arranged on each side of the end sealing plate (21).

4. The prestressed anchorage structure for the anchorage zone of a cable tower of a cable-stayed bridge according to claim 2, wherein The end sealing plate (21) is a circular plate, and the cylinder (22) is in the shape of a truncated cone.

5. The cable anchorage zone of a cable-stayed bridge according to any one of claims 2 to 4, wherein A through hole is formed in the end sealing plate (21) and communicates with the prestress pipe (30).

6. The pre-stressed anchorage structure of a cable tower anchorage zone of a cable-stayed bridge according to any one of claims 2-4, characterized in that, The end sealing plate (21) is perpendicular to the prestress pipe (30).

7. The prestressed anchorage structure of a cable tower anchorage zone of a cable-stayed bridge according to any one of claims 2-4, characterized in that, One end of the vertical main reinforcements (11) and the hoop stirrups (12) at the steel notches (20) on the steel reinforcement framework (10) is arranged in close contact with the cylinder (22).

8. The prestressed anchorage structure for the anchorage zone of a cable tower of a cable-stayed bridge according to claim 7, wherein One end of the vertical main reinforcements (11) and the hoop stirrups (12) at the steel notches (20) on the steel reinforcement framework (10) is fixedly connected with the cylinder (22).

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