A new type of steel box girder rigid frame bridge prestressed anchor rod anchoring structure

Abstract

The utility model discloses a novel steel box girder rigid frame bridge prestressed anchor rod anchoring structure belongs to the anchoring technical field, including steel box girder and concrete abutment, the steel box girder end portion is provided with the beam end closing plate, the concrete abutment is inlayed with upper steel backing plate, lower steel backing plate and side steel backing plate, the upper steel backing plate and lower steel backing plate are along the vertical direction and are corresponded to the beam end closing plate setting, the side steel backing plate is located the four -around of upper steel backing plate, the beam end closing plate, upper steel backing plate and lower steel backing plate are equipped with the prestressed threaded steel bar between the wear, the both ends of prestressed threaded steel bar are provided with the nut, the steel box girder is inlayed with the anchor concrete, the utility model discloses a kind of steel box girder rigid frame bridge prestressed anchor rod anchoring structure of improving anchoring strength and bearing capacity, guarantee the comfort of driving.

Description

Technical Field

[0001] This utility model relates to the field of anchoring technology, and in particular to a novel prestressed anchor bolt anchoring structure for steel box girder rigid frame bridges. Background Technology

[0002] In the construction of urban landscape bridges, the use of steel box girder rigid frame bridges can significantly reduce the positive bending moment at mid-span of the main girder, lower the height of the main girder at mid-span, and increase the clearance under the bridge, thereby meeting the navigation requirements under the bridge. At the same time, rigid frame bridges have no expansion joints on the bridge deck and no supports at the supports, resulting in high driving comfort. Therefore, steel box girder rigid frame bridges have unique advantages in the selection of urban landscape bridge types. For steel box girder rigid frame bridges, the anchorage connection between the steel box girder and the concrete abutment is a key technical issue. Traditional anchorage structures are prone to problems such as insufficient connection rigidity, insufficient load-bearing capacity, or easy corrosion of prestressed components. Utility Model Content

[0003] In order to overcome the shortcomings of the prior art, the technical problem to be solved by this utility model is to propose a prestressed anchor bolt anchorage structure for steel box girder rigid frame bridges that improves anchorage strength and bearing capacity and ensures driving comfort.

[0004] To achieve this objective, the present invention adopts the following technical solution: This utility model provides a novel prestressed anchor bolt anchoring structure for a steel box girder rigid frame bridge, including a steel box girder and a concrete abutment. The end of the steel box girder is provided with a beam end sealing plate. An upper steel pad, a lower steel pad, and a side steel pad are pre-embedded in the concrete abutment. The upper steel pad and the lower steel pad are arranged vertically corresponding to the beam end sealing plate, and the side steel pad is located around the upper steel pad. Prestressed threaded steel bars are threaded between the beam end cap plate, the upper steel pad plate, and the lower steel pad plate. Nuts are provided at both ends of the prestressed threaded steel bars. Sealing concrete is poured inside the steel box girder.

[0005] The preferred technical solution of this utility model is that multiple sets of reinforcing bars are arranged between the upper steel pad and the lower steel pad.

[0006] The preferred technical solution of this utility model is that the reinforcing bars are arranged at intervals along the circumference of the upper steel plate and the lower steel plate.

[0007] The preferred technical solution of this utility model is that the beam end sealing plate, the upper steel pad plate and the lower steel pad plate are all provided with reserved holes adapted to the prestressed threaded steel bars.

[0008] A preferred embodiment of this utility model is that a corrugated pipe is sleeved on the prestressed threaded steel bar, the corrugated pipe is located between the upper steel pad and the lower steel pad, and a grouting pipe is connected to the corrugated pipe.

[0009] A preferred embodiment of this invention is that an anchor plate is provided between the beam end sealing plate and the nut.

[0010] Compared with the prior art, the beneficial effects of this utility model are as follows: This utility model utilizes the tensioning of prestressed threaded steel bars and the cooperation of steel pads to transfer external forces through friction, ensuring a rigid connection between the steel box girder and the concrete abutment, effectively transferring shear force and bending moment, and achieving rigid anchorage. The pretension of a single φ32 prestressed threaded steel bar reaches 591KN, which can withstand shear force and tension under loads such as automobiles and crowds, providing sufficient bearing capacity. Rigid connections reduce the positive bending moment at mid-span of the main beam, lower the main beam height, increase the clearance under the bridge, and meet navigation requirements; the absence of expansion joints and supports improves driving comfort; the sealing concrete isolates corrosion factors, protects the prestressed threaded steel bars, and extends the structural life; the reinforcement of steel bars improves the integrity between the upper and lower steel plates, and the side steel plates enhance the lateral load-bearing capacity, further improving anchorage stability. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the anchor bolt anchoring structure provided in a specific embodiment of this utility model; Figure 2 This is provided in a specific embodiment of the present utility model. Figure 1 Sectional view of AA; Figure 3 This is provided in a specific embodiment of the present utility model. Figure 1 BB section view; Figure 4 This is provided in a specific embodiment of the present utility model. Figure 1 CC section view; Figure 5 This is provided in a specific embodiment of the present utility model. Figure 4 DD section view; Figure 6 This is provided in a specific embodiment of the present utility model. Figure 1 Enlarged schematic diagram of the structure at point A in the middle; Figure 7 This is provided in a specific embodiment of the present utility model. Figure 1 Enlarged schematic diagram of the structure at point B.

[0012] The attached diagram lists the components represented by each number as follows: 1. Steel box girder; 2. Concrete abutment; 3. Beam end cap; 4. Anchorage concrete; 5. Upper steel pad; 6. Lower steel pad; 7. Side steel pad; 8. Prestressed threaded steel bar; 81. Corrugated pipe; 82. Grouting pipe; 9. Nut; 10. Reinforcing steel bar. Detailed Implementation

[0013] The technical solution of this utility model will be further described below with reference to the accompanying drawings and specific embodiments.

[0014] A novel prestressed anchor bolt anchoring structure for a steel box girder rigid frame bridge includes a steel box girder 1 and a concrete abutment 2. The steel box girder 1 is provided with a beam end sealing plate 3 at its end. The concrete abutment 2 is pre-embedded with an upper steel pad 5, a lower steel pad 6 and a side steel pad 7. The upper steel pad 5 and the lower steel pad 6 are arranged vertically corresponding to the beam end sealing plate 3. The side steel pad 7 is located around the upper steel pad 5. Prestressed threaded steel bars 8 are threaded between the beam end sealing plate 3, the upper steel pad plate 5, and the lower steel pad plate 6. The prestressed threaded steel bars 8 are φ32, the tension control stress is 735MPa, and the pretension force provided by a single prestressed threaded steel bar 8 is 591KN. Nuts 9 are provided at both ends of the prestressed threaded steel bars 8. Sealing concrete 4 is poured inside the steel box girder 1. The beam end sealing plate 3, the upper steel pad plate 5, and the lower steel pad plate 6 are all provided with reserved holes that are compatible with the prestressed threaded steel bars 8.

[0015] Before pouring the concrete abutment 2, the upper steel pad 5, lower steel pad 6, and side steel pad 7 are pre-embedded according to the design positions, ensuring that they correspond to the positions of the beam end sealing plate 3 at the end of the steel box girder 1. Pre-drilled holes are made in the beam end sealing plate 3, upper steel pad 5, and lower steel pad 6 to provide channels for the prestressed threaded steel bars 8 to pass through. The prestressed threaded steel bars 8 are passed through the pre-drilled holes in the beam end sealing plate 3, upper steel pad 5, and lower steel pad 6. The abutment concrete is then poured, so that the pre-embedded steel pads, steel bars, etc., form an integral structure with the concrete abutment 2, providing foundation support for subsequent anchorage. After the abutment concrete reaches the design strength, the prestressed threaded steel bars 8 are tensioned. The steel box girder 1 is pressed tightly against the end sealing plate 3 and the upper steel pad 5, and the friction of the contact surface is used to prevent mutual slippage, so as to realize the transfer of external force. The lower steel pad 6, the upper steel pad 5 and the prestressed threaded steel bar 8 are locked by nuts 9 respectively to complete the rigid anchorage. The sealing concrete 4 is poured into the steel box girder 1 to form a protective wrap around the connection part of the beam end. The load borne by the steel box girder 1 is transferred to the prestressed threaded steel bar 8 through the end sealing plate 3, and then transferred to the upper steel pad 5 and the lower steel pad 6 by the prestressed threaded steel bar 8, and finally distributed to the concrete abutment 2, so as to realize the orderly transfer of load.

[0016] By employing the synergistic action of pre-embedded upper steel plate 5, lower steel plate 6, prestressed threaded steel bars 8, and sealing concrete 4, rigid anchorage between the steel box girder 1 and the concrete abutment 2 is achieved. This enhances the overall stability, deformation resistance, and durability of the structure, making it suitable for critical connection points in rigid frame bridges. It can meet the requirements of long-term load-bearing and complex working conditions. Specifically, the upper steel plate 5 and lower steel plate 6, in conjunction with the prestressed threaded steel bars 8, transmit external forces through friction generated by tension, thus solving the anchorage reliability problem; the sealing concrete 4 provides corrosion protection. The overall structure ensures effective transmission of external forces, providing foundation bearing capacity support for the bridge.

[0017] As a possible implementation of this solution, preferably, multiple sets of reinforcing bars 10 are arranged between the upper steel pad 5 and the lower steel pad 6. The reinforcing bars 10 between the upper steel pad 5 and the lower steel pad 6 can connect the two into a whole, avoiding independent deformation of a single upper steel pad 5 or lower steel pad 6 under stress. When the prestressed threaded steel bar 8 transmits the load to the upper steel pad 5 and the lower steel pad 6, the reinforcing bars 10 can disperse the stress, improve the anchorage strength between the upper steel pad 5 and the lower steel pad 6 and the concrete abutment 2, prevent the upper steel pad 5 and the lower steel pad 6 from being "pulled out" of the concrete due to excessive local stress, and enhance the bearing capacity of the pre-embedded upper steel pad 5 and the lower steel pad 6.

[0018] As a possible implementation of this solution, preferably, the reinforcing bars 10 are arranged at intervals along the circumference of the upper steel pad 5 and the lower steel pad 6, which can make the stress on the upper steel pad 5 and the lower steel pad 6 evenly distributed along the circumference, avoiding the problem of local stress concentration caused by the concentrated arrangement of the reinforcing bars 10. The circumferentially spaced arrangement can form a ring reinforcement effect, making the deformation resistance of the upper steel pad 5 and the lower steel pad 6 consistent in all directions, further improving the integrity and stress stability of the upper steel pad 5 and the lower steel pad 6.

[0019] As a possible implementation of this solution, preferably, a corrugated pipe 81 is sleeved on the prestressed threaded steel bar 8. The corrugated pipe 81 is located between the upper steel pad 5 and the lower steel pad 6. A grouting pipe 82 is connected to the corrugated pipe 81. The corrugated pipe sleeve 81 is located outside the prestressed threaded steel bar 8, which can isolate the prestressed threaded steel bar 8 from the external concrete and avoid the problem of uneven bonding caused by cement slurry directly wrapping the prestressed threaded steel bar 8 during concrete pouring. At the same time, the corrugated pipe 81 provides an independent space for the prestressed threaded steel bar 8, reducing the additional stress generated by concrete shrinkage. The grouting pipe 82 can inject cement slurry into the corrugated pipe 81 to fill the gap between the prestressed threaded steel bar 8 and the corrugated pipe 81, forming a sealed anti-corrosion layer to prevent steel bar corrosion and improve structural durability.

[0020] As a possible implementation of this solution, preferably, an anchor plate 31 is provided between the beam end sealing plate 3 and the nut 9, which can distribute the concentrated pressure of the nut 9 to a larger area of ​​the beam end sealing plate 3, avoiding local dents or deformation of the sealing plate caused by "point contact" when the nut 9 directly contacts the sealing plate. The pressure-dispersing effect of the anchor plate 31 can protect the structural integrity of the beam end sealing plate 3, ensure its long-term stable load transmission, and extend the service life of the beam end sealing plate 3.

[0021] This utility model has been described through preferred embodiments. Those skilled in the art will understand that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of this utility model. This utility model is not limited to the specific embodiments disclosed herein; other embodiments falling within the scope of the claims of this application are all within the protection scope of this utility model.

Claims

1. A novel prestressed anchorage structure for steel box girder rigid frame bridges, characterized in that: The bridge includes a steel box girder (1) and a concrete abutment (2). The steel box girder (1) is provided with a beam end sealing plate (3) at its end. The concrete abutment (2) is pre-embedded with an upper steel pad (5), a lower steel pad (6) and a side steel pad (7). The upper steel pad (5) and the lower steel pad (6) are set vertically to correspond to the beam end sealing plate (3). The side steel pad (7) is located around the upper steel pad (5). Prestressed threaded steel bars (8) are threaded between the beam end sealing plate (3), the upper steel pad plate (5) and the lower steel pad plate (6). Nuts (9) are provided at both ends of the prestressed threaded steel bars (8). Sealing concrete (4) is poured inside the steel box girder (1).

2. The novel prestressed anchor bolt anchoring structure for a steel box girder rigid frame bridge according to claim 1, characterized in that: Multiple sets of reinforcing bars (10) are arranged between the upper steel pad (5) and the lower steel pad (6).

3. The novel prestressed anchor bolt anchoring structure for a steel box girder rigid frame bridge according to claim 2, characterized in that: The reinforcing bars (10) are arranged at intervals along the circumference of the upper steel pad (5) and the lower steel pad (6).

4. The novel prestressed anchor bolt anchoring structure for a steel box girder rigid frame bridge according to claim 1, characterized in that: The beam end sealing plate (3), the upper steel pad plate (5) and the lower steel pad plate (6) are all provided with reserved holes that are compatible with the prestressed threaded steel bars (8).

5. The novel prestressed anchor bolt anchoring structure for a steel box girder rigid frame bridge according to claim 1, characterized in that: The prestressed threaded steel bar (8) is fitted with a corrugated pipe (81), which is located between the upper steel pad (5) and the lower steel pad (6), and a grouting pipe (82) is connected to the corrugated pipe (81).

6. The novel prestressed anchor bolt anchoring structure for a steel box girder rigid frame bridge according to claim 1, characterized in that: An anchor plate (31) is provided between the beam end sealing plate (3) and the nut (9).

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