Steel beam in pre-tensioned beam diverter

Abstract

This utility model provides a steel strand steering device for pre-tensioned beams, including an anti-tension pile, a steel plate, a pin, and fasteners. The anti-tension pile is sunk and installed on a pedestal, with a support extending upward from its top. The steel plate is fixed inside the precast beam, with its bottom protruding through the precast beam. Several steel strand pre-reserved holes are arranged at intervals on the steel plate. The pre-reserved holes are standardized holes, and their spacing is designed according to the angle and number of steel strand folds. The support and the bottom of the steel plate are respectively provided with pin holes, and the pin passes through the pin holes. The pin passing through the pin hole of the support and the pin hole at the bottom of the steel plate form a rotating connection structure, allowing the steel plate to rotate freely around the pin, adapting to the angle changes during the steel strand tensioning process, thereby reducing the compressive force between the steel strand and the steering device and reducing the stress complexity of the steering device. The fasteners are located on one side of the support and clamp the pin, so that the support and the steel plate can rotate around the pin without detaching from it.

Description

Technical Field

[0001] This utility model relates to the field of bridge construction technology, and in particular to a pre-tensioned beam internal steel strand deflector, which is suitable for prefabrication construction of small and medium span bridges with spans of 10-20 meters. Background Technology

[0002] In the design and construction of bridges with small and medium spans, prestressed concrete hollow slab beams are the mainstream structural form. The pre-tensioning method has become a commonly used method for making hollow slab beams due to its advantages such as convenient factory prefabrication, low hoisting requirements, fast construction speed, and low cost.

[0003] However, pre-tensioned beams have obvious technical shortcomings. It is difficult to achieve a zigzag arrangement of the prestressed steel strands. Existing technologies mostly use straight strands, which require some steel strands to be actively deactivated at the beam ends through sleeves or other means to meet the stress requirements of the beam, resulting in waste of steel strand materials. At the same time, straight strand arrangement cannot fully improve the shear strength of the beam, the bond between the steel strands and concrete is insufficient, and the steel strands are prone to corrosion due to exposure to or contact with corrosive media.

[0004] Using vertical zigzag strands can effectively solve the above problems, including improving the shear strength of the beam, avoiding waste of steel strands, enhancing the bond between steel strands and concrete, and reducing the risk of steel strand corrosion.

[0005] However, the steering gear devices that existing zigzag fabric harness solutions rely on have problems such as poor reliability and weak economy, and cannot meet the actual construction needs. Therefore, there is an urgent need for a steering device that is structurally stable, cost-controllable, and compatible with zigzag fabric harnesses. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this utility model provides a pre-tensioned beam internal steel strand steering mechanism, which achieves stable guidance of the zigzag steel strand arrangement, reduces steel strand damage and steering mechanism stress, and simultaneously improves the reusability and construction adaptability of some components. The technical solution adopted by this utility model is as follows: A pre-tensioned beam internal steel strand steering mechanism, comprising: The anti-tension pile is set on a platform and its top extends upward to provide a support part. A steel plate is fixed inside a precast beam, with its bottom protruding from the precast beam. Several pre-reserved holes for steel strands are arranged at intervals on the steel plate. A pin shaft is provided at the bottom of the support part and the bottom of the steel plate, and the pin shaft passes through the pin hole. Fasteners are located on one side of the support and clamp the pin so that the support and the steel plate can rotate around the pin without disengaging from it.

[0007] Furthermore, there are two support parts, which are arranged laterally at intervals on the top of the tension piles. The bottom of the steel plate extends into the gap between the two support parts, and fasteners are respectively installed on the side of the two tension piles facing away from each other.

[0008] Furthermore, the fastener is an anti-slip buckle.

[0009] Furthermore, the steel plate is an HN type steel.

[0010] Furthermore, a plastic flexible tube is installed inside the reserved hole.

[0011] Advantages of this utility model: The pin-rotating structure reduces the compressive force between the steel strand and the steering gear, reduces the stress complexity of the steering gear, and eliminates the bending moment effect of the steel strand tension on the steering gear; the pin, as a temporary component, can be reused multiple times, reducing engineering costs. The dual fixing structure of the anti-tension pile and fastener limit prevents the steering gear from shifting or detaching during tensioning, thus improving structural stability. The fasteners and pins can be disassembled and reused, reducing the cost of a single construction. The anti-tension pile is sunk into the platform, leaving operating space to accommodate fasteners and pins, facilitating their assembly and disassembly. The steel plate portion remains outside the beam and can be used as an embedded part for pipeline hangers and other components in the later stages of precast beam construction, saving the need for additional drilling and embedding procedures. If not necessary, it can also be cut off. Attached Figure Description

[0012] Figure 1 This is a cross-sectional view of the steering gear.

[0013] Figure 2 This is an elevation view of the steering gear.

[0014] Figure 3 This is a cross-sectional view of the steering gear under construction conditions.

[0015] Figure 4 This is an elevation view of the steering gear under construction conditions.

[0016] In the diagram: 100-tension pile, 110-support part, 200-steel plate, 210-reserved hole, 300-pin, 400-fastener, 500-base, 600-precast beam bottom formwork, 700-folded steel strand, 800-horizontal steel strand. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this utility model and are not intended to limit this utility model.

[0018] Please see the appendix Figure 1 - Appendix Figure 4 This application proposes a pre-tensioned beam internal steel strand steering device, including an anti-tension pile 100, a steel plate 200, a pin 300, and a fastener 400.

[0019] The tension pile 100 is sunk and installed on the platform 500, with a support part 110 extending upward from its top. As the basic connecting component of the steering gear, the tension pile 100 is sunk and installed on the precast beam platform 500. After the connecting steel plate 200, the tension of the steel strand is transmitted to the tension pile 100 through the steel plate. The tension pile 100 generally relies on its own weight to bear the vertical tension during the steering process, thus avoiding overall displacement of the device. When the tension pile 100 is sunk and installed, an operating space can be formed between the platform 500 and the precast beam base to accommodate the pin 300 and fastener 400, which facilitates the reuse of the pin 300 and fastener 400.

[0020] A steel plate 200 is fixed inside a precast beam, with its bottom protruding through the precast beam. Several pre-drilled holes 210 for steel strands are spaced apart on the steel plate 200. Specifically, the steel plate 200 is an HN-shaped steel section. Plastic flexible tubes are pre-installed within the pre-drilled holes 210 at positions corresponding to the steel strands. The steel plate, manufactured using existing HN-shaped steel, combines high strength with economy. The steel plate 200 is primarily cast inside the precast beam, protruding through the precast beam at its bottom and engaging with the support part 110. The pre-drilled holes 210 are standardized openings, their spacing designed according to the angle and number of steel strands. The plastic flexible tubes are used to isolate the steel strands from the steel plate 200, reducing mechanical damage caused by compression, lowering bending moment, and reducing the stress complexity of the steering gear.

[0021] The bottom of the support part 110 and the steel plate 200 are respectively provided with pin holes, and the pin shaft 300 passes through the pin holes; the pin shaft 300 passing through the pin hole of the support part 110 and the pin hole at the bottom of the steel plate 200 form a rotating connection structure, allowing the steel plate 200 to rotate freely around the pin shaft, adapting to the angle changes during the tensioning process of the steel strand, thereby reducing the compressive force between the steel strand and the steering gear and reducing the stress complexity of the steering gear.

[0022] Fastener 400 is located on one side of the support portion 110 and clamps the pin 300, so that the support portion 110 and the steel plate 200 can rotate around the pin 300 without disengaging from the pin 300. The fastener 400 is specifically a commonly used fastening structure such as an anti-slip buckle or a clamp.

[0023] In one specific embodiment, there are two support parts 110, arranged laterally at intervals on the top of the tension piles 100. The bottom of the steel plate 200 extends into the gap between the two support parts 110, and fasteners 400 are respectively provided on the side of the two tension piles 100 facing away from each other. (See attached...) Figure 1As shown, after the pin 300 passes through the support part 110 and the steel plate 200 respectively, the pin 300 is clamped with two fasteners 400 to restrict both ends of the pin 300, ensuring that the support part 110 and the steel plate 200 do not detach from the pin when rotating around the pin, and at the same time preventing the pin 300 from axial displacement during the force process, thus improving the connection stability.

[0024] See attached document Figure 2 Appendix Figure 3 and attached Figure 4 The steering gear installation process is briefly described below: Process the tension pile 100, select steel plate (such as 200 HN150×75 steel, 10mm thick, with 6 reserved holes of 25mm diameter, and 2mm thick plastic hoses inside the holes), pin 300, and fastener 400; clean the surface of the precast beam platform 500 and mark the installation position of the tension pile; Excavate a foundation pit at the marked position 500 on the pedestal, place the pull-out piles into the foundation pit, and align the pin holes of the two support parts 110; insert the bottom of the steel plate 200 into the gap between the two support parts 110, so that the pin holes of the steel plate 200 are aligned with the pin holes of the support parts 110; insert the pin shaft 300, and install fasteners 400 on both sides of the support parts 110, ensuring that the fasteners 400 are tightly attached to the support parts and that the pin shaft 300 has no axial displacement; Following the pre-tensioned beam construction process, the precast beam reinforcement is tied, and the zigzag steel strands are passed through the reserved holes 210 of the steel plate 200, keeping the steel strands in contact with the inner wall of the plastic hose; the precast beam formwork is installed, and concrete is poured, ensuring that the concrete covers the main body of the steel plate (only the bottom protrudes from the beam), and is vibrated to compact it, avoiding voids. The steel plate 200 is poured into the precast beam to form a whole with the precast beam; After the concrete strength reaches 90% of the design value, the steel strands are tensioned. During the tensioning process, the steel plate 200 rotates freely around the pin 300 to adapt to the change in the angle of the steel strand. After tensioning, the beam is cured. After curing, the fasteners 400, pin 300, and tension piles 100 are removed and reused. The exposed steel plate 200 can be retained as an embedded part as needed, or the exposed part can be cut off by gas cutting.

[0025] In summary, compared with the existing pre-tensioned beam steel strand steering technology, this invention solves the problems of low reliability and poor economy of existing steering devices by using a detachable rotating connection between the anti-tension pile 100 and the steel plate; functionally, it realizes the zigzag arrangement of steel strands, improves the mechanical properties of the beam, and avoids material waste.

[0026] Finally, it should be noted that the above specific embodiments are only used to illustrate the technical solution of this utility model and not to limit it. Although this utility model has been described in detail with reference to examples, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solution of this utility model without departing from the spirit and scope of the technical solution of this utility model, and all such modifications and substitutions should be covered within the scope of the claims of this utility model.

Claims

1. A pre-tensioned beam internal steel strand steering mechanism, characterized in that, include: An anti-tension pile (100) is set on a platform, and a support part (110) extends upward from its top. A steel plate (200) is fixed inside a precast beam, with its bottom protruding through the precast beam. Several steel strand pre-reserved holes (210) are arranged at intervals on the steel plate (200). The bottom of the support part (110) and the steel plate (200) are respectively provided with pin holes, and the pin (300) passes through the pin holes; Fastener (400) is located on one side of the support (110) and clamps the pin (300) so that the support (110) and the steel plate (200) can rotate about the pin (300) without disengaging from the pin (300).

2. The pre-tensioned beam internal steel strand deflector as described in claim 1, characterized in that: The number of the support parts (110) is two, which are arranged laterally at the top of the tension piles (100). The bottom of the steel plate (200) extends into the gap between the two support parts (110). Fasteners (400) are respectively provided on the side of the two tension piles (100) facing away from each other.

3. The pre-tensioned beam internal steel strand steering gear as described in claim 2, characterized in that: The fastener (400) is an anti-slip buckle.

4. The pre-tensioned beam internal steel strand deflector as described in claim 1, characterized in that: The steel plate (200) is an HN type steel.

5. The pre-tensioned beam internal steel strand deflector as described in claim 1, characterized in that: A plastic hose is installed inside the reserved hole (210).

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