Temporary anchoring structure of steel-concrete composite beam cable-stayed bridge

Abstract

The utility model relates to the technical field of bridge engineering construction, in particular to a temporary anchoring structure of a steel-concrete composite beam cable-stayed bridge, which comprises a plurality of steel beams which are evenly and symmetrically distributed on a bridge tower, one end of each steel beam is anchored in the bridge tower, the other end of each steel beam is exposed out of the bridge tower, and the temporary anchoring structure further comprises a plurality of anchoring boxes which comprise outer boxes. The outer box is fixed to a bridge tower, the top of the outer box is tightly attached to and fixed to the bottom of the steel-concrete composite beam, the bottom of the outer box is perpendicular to the steel beam, and the other end of the steel beam is fixedly connected with the outer box in the outer box. The anchoring box is installed between the steel-concrete composite beam and the bridge tower, the space of a construction area is expanded, the top of the anchoring box is connected with the steel-concrete composite beam, the strength of a connecting area is enhanced, the bottom of the outer box is perpendicular to the steel beam, the possibility that the steel beam generates shearing force in the using process is reduced, and the breaking risk of the steel beam is reduced.

Description

Technical Field

[0001] This utility model relates to the field of bridge engineering construction technology, and in particular to a temporary anchorage structure for a steel-concrete composite beam cable-stayed bridge. Background Technology

[0002] Steel-concrete composite girder cable-stayed bridges have become a favorite among builders and designers because they can make full use of the properties of steel and concrete materials. Steel-concrete composite girder bridges are generally constructed using bridge deck cranes for cantilever construction. However, under the action of steel beam hoisting, bridge deck installation, cable tensioning, temporary construction loads, wind loads, and temperature loads, unbalanced loads will appear on both sides of the cantilever. The bending moment generated by the unbalanced load will cause the main beam to rotate, the horizontal load will cause the main beam to move longitudinally, and the horizontal load will cause the main beam to move laterally. The main beam structure may face safety risks such as displacement, overturning, and collapse.

[0003] To address safety issues caused by unbalanced loads, existing technologies typically employ temporary anchorage structures between the steel-concrete composite beam and the bridge tower. These structures constrain the steel-concrete composite beam at the bridge tower location, ensuring safety during cantilever construction. However, the construction area for these temporary anchorage structures is often limited, making installation inconvenient for technicians. Furthermore, existing temporary anchorage structures are usually directly placed on the steel-concrete composite beam, which can easily concentrate stress at the anchorage location under unbalanced loads, leading to deformation of the steel-concrete composite beam. Additionally, since the longitudinal direction of the bridge is generally at an angle to the horizontal plane, the steel-concrete composite beam can exert shear forces on the steel strands, increasing the risk of fracture. Utility Model Content

[0004] The main purpose of this utility model is to provide a temporary anchorage structure for a steel-concrete composite beam cable-stayed bridge, so as to solve the technical problems of inconvenient construction of temporary anchorage structures in the prior art, which easily cause deformation of steel-concrete composite beams and easy breakage of steel strands.

[0005] To achieve the above objectives, this utility model provides a temporary anchorage structure for a steel-concrete composite beam cable-stayed bridge, comprising multiple steel strands evenly and symmetrically distributed on the bridge tower. One end of each steel strand is anchored inside the bridge tower, while the other end protrudes from the tower. The structure also includes multiple anchorage boxes, each comprising an outer box fixed to the bridge tower. The top of the outer box is tightly attached to and fixed to the bottom of the steel-concrete composite beam, and the bottom of the outer box is perpendicular to the steel strands. The other end of each steel strand is fixedly connected to the outer box within it.

[0006] Furthermore, the anchoring box also includes an inner box, which is fixed to the bottom of the outer box. The top of the inner box is provided with a clustering hole, and the other end of the steel strand passes through the clustering hole and is fixedly connected to the inner box.

[0007] More preferably, it also includes a corrugated pipe, which wraps around the outer periphery of the steel strand anchored inside the bridge tower, with the top of the corrugated pipe protruding from the bridge tower and the exposed height being less than the height of the inner box.

[0008] Furthermore, the anchor box also includes a tension nut, which is connected to the other end of the steel strand.

[0009] Furthermore, the bridge tower also includes a pre-embedded steel plate, which is perpendicular to the steel strand. The pre-embedded steel plate has through holes for the steel strand to pass through, and the bottom of the outer box is attached to and connected to the pre-embedded steel plate.

[0010] Furthermore, it also includes a reinforcing plate, the top tilt angle of the outer box is consistent with the tilt angle of the steel-concrete composite beam, and the reinforcing plate, the steel-concrete composite beam and the outer box are sequentially attached to each other and fixedly connected by bolts.

[0011] More preferably, the reinforcing plate is an L-shaped reinforcing plate, and both ends of the L-shaped reinforcing plate are fixedly connected to the steel-concrete composite beam.

[0012] Furthermore, the multiple steel strands are divided into four groups of steel strands, each group including four steel strands. The four steel strands are arranged in a centrally symmetrical manner, and the anchor box is provided with a cross support to separate the four steel strands. The four groups of steel strands are centrally symmetrically distributed on the bridge tower along the axis of symmetry of the steel-concrete composite beam.

[0013] Furthermore, it also includes multiple longitudinal restraint plates, which are arranged opposite each other along the longitudinal direction of the steel-concrete composite beam. The longitudinal restraint plates are fixed to the bottom of the steel-concrete composite beam, and the relative distance between the longitudinal restraint plates is greater than or equal to the width of the bridge tower's pad stone.

[0014] Furthermore, the longitudinal constraint plate includes a longitudinal plate and a transverse plate, with one side of the longitudinal plate and the transverse plate being fixedly connected perpendicularly to each other, and the other side of the transverse plate facing and abutting against the pad stone of the bridge tower.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] The anchoring box described in this invention is installed between the steel-concrete composite beam and the bridge tower. The height of the anchoring box expands the construction area, facilitating construction by technicians. Secondly, the top of the anchoring box connects to the steel-concrete composite beam, increasing the connection area and strengthening the connection region, thus reducing the risk of stress concentration and deformation of the steel-concrete composite beam under unbalanced loads. Finally, the bottom of the outer box is perpendicular to the steel strands, reducing the possibility of shear forces generated by the steel strands during use and lowering the risk of steel strand breakage. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the anchor box connection position in one embodiment of the present invention;

[0019] Figure 2 This is a schematic diagram of the overall structure of the anchor box in one embodiment of the present invention;

[0020] Figure 3 This is a front view of the connection between the anchor box and the steel-concrete composite beam in one embodiment of the present invention;

[0021] Figure 4 This is a side view of the connection between the anchor box and the steel-concrete composite beam in one embodiment of the present invention;

[0022] Figure 5 This is a top view of the anchor box structure in one embodiment of the present invention;

[0023] Figure 6 This is a schematic diagram of the connection of the longitudinal constraint plate in one embodiment of the present invention;

[0024] Figure 7 for Figure 6 Enlarged cross-sectional view at point AA in the diagram;

[0025] Figure 8 for Figure 7 Enlarged cross-sectional view of section BB in the diagram;

[0026] Figure 9 This is a schematic diagram of the connection of the transverse constraint block in one embodiment of the present invention.

[0027] The purpose, features, and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings.

[0028] Explanation of icon numbers:

[0029] 1. Anchorage box; 11. Outer box; 12. Inner box; 13. Tensioner nut; 2. Steel strand; 3. Corrugated pipe; 4. Connecting pipe; 5. Reinforcing plate; 6. Longitudinal restraint plate; 61. Transverse plate; 62. Longitudinal plate; 7. Pad stone; 8. Transverse restraint block; 100. Steel-concrete composite beam; 200. Bridge tower. Detailed Implementation

[0030] It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0031] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0032] 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.

[0033] Furthermore, the use of terms such as "first" and "second" in this utility model 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. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this utility model.

[0034] Please see Figures 1 to 9 This embodiment provides a temporary anchorage structure for a steel-concrete composite beam cable-stayed bridge. The temporary anchorage structure provides vertical constraint for the steel-concrete composite beam 100. The temporary anchorage structure includes multiple steel strands 2, which are evenly and symmetrically distributed on the bridge tower 200. One end of the steel strand 2 is anchored inside the bridge tower 200, and the other end of the steel strand 2 protrudes from the bridge tower 200. It also includes multiple anchorage boxes 1, each of which includes an outer box 11. The outer box 11 is fixed to the bridge tower 200. The top of the outer box 11 is in close contact with and fixed to the bottom of the steel-concrete composite beam 100. The bottom of the outer box 11 is perpendicular to the steel strands 2. The other end of the steel strand 2 is fixedly connected to the outer box 11 inside the outer box 11.

[0035] In this embodiment, the steel strand 2 is anchored inside the bridge tower 200. When unbalanced loads cause the steel-concrete composite beam 100 to shift vertically, the prestressed steel strand 2 provides tensile force to resist the shift. The anchor box 1 is installed between the steel-concrete composite beam 100 and the bridge tower 200. The height of the anchor box 1 expands the construction area, facilitating construction by technicians. Secondly, the top of the anchor box 1 is connected to the steel-concrete composite beam 100, increasing the connection area, strengthening the connection area, and reducing the risk of stress concentration and deformation of the steel-concrete composite beam 100 under unbalanced loads. Finally, the bottom of the outer box 11 is perpendicular to the steel strand 2, reducing the possibility of shear force generated by the steel strand 2 during use and reducing the risk of breakage of the steel strand 2.

[0036] Furthermore, in the prior art, the holes through which the steel strands 2 pass need to be drilled on-site according to the pre-embedded position of the steel strands 2 in the bridge tower 200. The accuracy between the hole position and the steel strands 2 is difficult to guarantee. However, in this embodiment, the anchor box 1 and the steel-concrete composite beam 100 can be manufactured in advance in the factory. The steel strands 2 are first connected and fixed to the anchor box 1, and then the anchor box 1 and the steel-concrete composite beam 100 are connected by bolts, which greatly improves the connection accuracy of the steel strands 2 and further reduces the risk of shear failure of the steel strands 2.

[0037] In one embodiment, such as Figures 1 to 5 As shown, the anchoring box 1 also includes an inner box 12, which is fixed to the bottom of the outer box 11. The top of the inner box 12 has a clustering hole, through which the other end of the steel strand 2 passes and is fixedly connected to the inner box 12. One end of the steel strand 2 is anchored within the bridge tower 200, and the other end needs to have a certain height reserved. In this embodiment, the inner box 12 is provided, and the reserved steel strand 2 passes through the inner box 12 for fixation, facilitating the fixation of the steel strand 2 and the application of prestress. Furthermore, jacks are installed on the inner box 12 to tension each steel strand 2 in this embodiment to apply prestress. In this embodiment, the prestressed anchoring length of the steel strand 2 is 450cm, and the tensioning control force is 150t.

[0038] In a further preferred embodiment, the system also includes a corrugated pipe 3, which wraps around the outer periphery of the steel strand 2 anchored within the bridge tower 200. The top of the corrugated pipe 3 protrudes from the bridge tower 200, and its exposed height is less than the height of the inner box 12. The corrugated pipe 3, encasing the steel strand 2, is pre-embedded within the bridge tower 200, temporarily separating the steel strand 2 from the concrete of the bridge tower 200. This facilitates subsequent prestressing operations by technicians. The exposed height of the corrugated pipe 3, being less than the height of the inner box 12, facilitates the installation of the anchor box 1 and the jacks. In this embodiment, after tensioning the steel strand 2, no grouting is performed. Instead, the opening of the corrugated pipe 3 is sealed with grease, and the exposed steel strand 2 is wrapped with waterproof tape. Grouting is only performed into the corrugated pipe 3 after the bridge closure is completed and before the temporary consolidation is removed. Once the grout strength meets the specifications, the steel strand 2 is cut and removed. This embodiment also includes a connecting pipe 4 connecting adjacent corrugated pipes 3, with grout flowing into the adjacent corrugated pipes 3 through the connecting pipe 4.

[0039] Furthermore, the anchor box 1 also includes a tension nut 13, which is connected to the other end of the steel strand 2. After applying prestress by tensioning the steel strand 2 with a jack, the tension nut 13 is used to lock the steel strand 2, stabilizing the prestress, reducing the cost of using the jack, and improving the stability of the steel strand 2.

[0040] Furthermore, the bridge tower 200 also includes a pre-embedded steel plate, which is perpendicular to the steel strand 2. The pre-embedded steel plate has through holes for the steel strand 2 to pass through. The bottom of the outer box 11 is fitted and connected to the pre-embedded steel plate. To ensure the perpendicularity of the anchor box 1 and the steel strand 2, the pre-embedded steel plate ensures the flatness of the connection between the anchor box 1 and the bridge tower 200, improving the strength of the connection. Alternatively, a thin gasket can be used to ensure a tight fit between the bottom of the outer box 11 and the pre-embedded steel plate without gaps.

[0041] In one embodiment, such as Figure 3 and Figure 4 As shown, it also includes a reinforcing plate 5. The top inclination angle of the outer box 11 is consistent with the inclination angle of the steel-concrete composite beam 100. The reinforcing plate 5, the steel-concrete composite beam 100, and the outer box 11 are sequentially attached and fixedly connected by bolts. In this embodiment, an L-shaped reinforcing plate is used, with both ends of the L-shaped reinforcing plate fixedly connected to the steel-concrete composite beam 100. In this embodiment, the anchor box 1 is fixed at the middle web of the steel-concrete composite beam 100, where the steel-concrete composite beam 100 has high strength and good balance. One side of the L-shaped reinforcing plate and the anchor box 1 clamp the bottom plate of the steel-concrete composite beam 100, improving the shear and tensile strength of the bottom plate in the inclined state. The other side of the L-shaped reinforcing plate is fixed to the middle web, which can further improve the tensile strength.

[0042] See Figure 5In this embodiment, the steel strands 2 are further divided into four groups, each group comprising four steel strands 2, which are arranged symmetrically at the center. A cross-shaped support is provided inside the anchorage box 1 to separate the four steel strands 2. The four groups of steel strands are symmetrically distributed on the bridge tower 200 along the axis of symmetry of the steel-concrete composite beam 100. In this embodiment, the steel strands 2 are φ15-9 low-relaxation steel strands.

[0043] In one embodiment, such as Figure 7 and Figure 8 As shown, the system also includes multiple longitudinal restraint plates 6, which are arranged opposite each other along the longitudinal direction of the steel-concrete composite beam 100. The longitudinal restraint plates 6 are fixed to the bottom of the steel-concrete composite beam 100, and the relative distance between the longitudinal restraint plates 6 is greater than or equal to the width of the pad stone 7 of the bridge tower 200. Further, each longitudinal restraint plate 6 includes a longitudinal plate 62 and a transverse plate 61. The longitudinal plate 62 and the transverse plate 61 are fixedly connected perpendicularly to each other on one side, and the other side of the transverse plate 61 faces and abuts against the pad stone 7 of the bridge tower 200.

[0044] In this embodiment, the pad stone 7 that the longitudinal constraint plate 6 engages with is a damper pad stone. Positioned around the pad stone 7, the longitudinal constraint plates 6 engage with the front and rear sides of the pad stone 7, achieving longitudinal constraint of the steel-concrete composite beam 100. When the relative distance between the longitudinal constraint plates 6 is greater than the width of the pad stone 7, steel shims can be inserted to improve the constraint capacity of the longitudinal constraint plates 6. The filling height of the steel shims is 280mm, the width is 720mm, and the vertical clearance from the top surface of the pad stone 7 is 30mm. In this embodiment, the longitudinal constraint plates 6 are arranged in pairs and symmetrically at both ends of the steel-concrete composite beam 100. The longitudinal constraint plates 6 provide longitudinal constraint for the steel-concrete composite beam 100. When unbalanced loads cause longitudinal displacement of the steel-concrete composite beam 100, the longitudinal constraint plates 6 provide resistance against this displacement.

[0045] In one embodiment, such as Figure 9 As shown, transverse restraint blocks 8 are also inserted on both sides of the steel-concrete composite beam 100, positioned between the steel-concrete composite beam 100 and the bridge tower 200. The transverse restraint blocks 8 provide transverse restraint for the steel-concrete composite beam 100. When unbalanced loads cause the steel-concrete composite beam 100 to shift laterally, the transverse restraint blocks 8 provide resistance against this shift. Preferably, in this embodiment, the transverse restraint blocks 8 are square timbers, each 1m wide and 1m high, arranged at the bottom of the side web of the steel-concrete composite beam 100.

[0046] In the above embodiments, the present invention achieves constraints on the steel-concrete composite beam 100 in three dimensions: vertical, longitudinal, and transverse, thereby significantly improving the steel-concrete composite beam 100's resistance to unbalanced loads and reducing construction difficulty and safety risks.

[0047] The above are merely preferred embodiments of this utility model and do not limit the patent scope of this utility model. Any equivalent structural or procedural transformations made based on the description and drawings of this utility model, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A temporary anchorage structure for a steel-concrete composite beam cable-stayed bridge, comprising multiple steel strands uniformly and symmetrically distributed on the bridge towers, one end of each steel strand anchored inside the bridge tower, and the other end of each steel strand protruding from the bridge tower, characterized in that... It also includes multiple anchor boxes, each anchor box having an outer box fixed to the bridge tower. The top of the outer box is in close contact with and fixed to the bottom of the steel-concrete composite beam, and the bottom of the outer box is perpendicular to the steel strand. The other end of the steel strand is fixedly connected to the outer box inside the outer box.

2. The temporary anchoring structure according to claim 1, characterized in that, The anchor box also includes an inner box, which is fixed to the bottom of the outer box. The top of the inner box is provided with a clustering hole, and the other end of the steel strand passes through the clustering hole and is fixedly connected to the inner box.

3. The temporary anchoring structure according to claim 2, characterized in that, It also includes a corrugated pipe that wraps around the outer periphery of the steel strands anchored inside the bridge tower, with the top of the corrugated pipe protruding from the bridge tower and the exposed height being less than the height of the inner box.

4. The temporary anchoring structure according to claim 1, characterized in that, The anchor box also includes a tension nut, which is connected to the other end of the steel strand.

5. The temporary anchoring structure according to claim 1, characterized in that, The bridge tower also includes a pre-embedded steel plate, which is perpendicular to the steel strand. The pre-embedded steel plate has through holes for the steel strand to pass through, and the bottom of the outer box is attached to and connected to the pre-embedded steel plate.

6. The temporary anchoring structure according to claim 1, characterized in that, It also includes a reinforcing plate. The top tilt angle of the outer box is consistent with the tilt angle of the steel-concrete composite beam. The reinforcing plate, the steel-concrete composite beam and the outer box are sequentially attached and fixedly connected by bolts.

7. The temporary anchoring structure according to claim 6, characterized in that, The reinforcing plate is an L-shaped reinforcing plate, and both ends of the L-shaped reinforcing plate are fixedly connected to the steel-concrete composite beam.

8. The temporary anchoring structure according to claim 1, characterized in that, The multiple steel strands are divided into four groups, each group including four steel strands. The four steel strands are arranged in a centrally symmetrical manner, and the anchor box is provided with a cross support to separate the four steel strands. The four groups of steel strands are centrally symmetrically distributed on the bridge tower along the axis of symmetry of the steel-concrete composite beam.

9. The temporary anchoring structure according to any one of claims 1-8, characterized in that, It also includes multiple longitudinal restraint plates, which are arranged opposite each other along the longitudinal direction of the steel-concrete composite beam. The longitudinal restraint plates are fixed to the bottom of the steel-concrete composite beam, and the relative distance between the longitudinal restraint plates is greater than or equal to the width of the bridge tower's pad stone.

10. The temporary anchoring structure according to claim 9, characterized in that, The longitudinal constraint plate includes a longitudinal plate and a transverse plate. The longitudinal plate and the transverse plate are fixedly connected perpendicularly to each other on one side, and the other side of the transverse plate faces and abuts against the pad stone of the bridge tower.

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