A tensioning bottom wedge and bridge-building machine for prestressed continuous beams

Abstract

The embodiment of the present application provides a tensioning bottom wedge and a bridge-building machine for pre-tensioning prestressed continuous beams, wherein the tensioning bottom wedge comprises, from top to bottom, a lifting ring, a rocker assembly, a wedge seat assembly and a slider assembly; the lifting ring is detachably hinged to the top of the rocker assembly, and the bottom of the rocker assembly passes through the wedge seat assembly and is hinged to the slider assembly; both ends of the slider assembly are connected to the wedge seat assembly; the tensioning bottom wedge has the beneficial effects of being able to tension the steel strands and quickly unload the tensioning force while being easy to disassemble; and is applicable to the field of bridge manufacturing technology.

Description

Technical Field

[0001] The present application relates to the field of bridge manufacturing, and in particular to a tensioning bottom wedge and a bridge-building machine for pre-tensioning prestressed continuous beams. Background Art

[0002] Currently, continuous beam bridge construction utilizes cantilevered cast-in-place bridge-building machines. After the machine is finished pouring, vertical prestressed tendons are installed. Typically, vertical prestressing in box girder bridges designed in my country is constructed using post-tensioning, using high-quality rolled threaded steel bars. However, these bars lack a distinct yield point and exhibit no signs of failure, leading to brittle fracture. Furthermore, their brittle fracture strength decreases dramatically after contact with fire, and they are prone to defects in the parent material and break easily after impact.

[0003] In order to solve the above problems, it is necessary to consider using the pre-tensioning method for construction. In the pre-tensioning method, the tensioning mechanism tensions the prestressed steel strands before the beam is cast. When the bridge-building machine is cast, the steel strands combine with the beam concrete to generate vertical prestress in the beam. After the concrete is cast, the tensioning mechanism needs to have an unloading function.

[0004] For this purpose, an installation device for vertical prestressed steel strands for continuous beam construction has been proposed, which includes a separate welded pipe, a clamping joint, and a sleeve. The steel strands are passed through the separate welded pipe, and the two separate welded pipes are fixedly connected by the clamping joint. The lower end of the separate welded pipe is fixedly connected to the upper end of the sleeve, and the lower end of the sleeve is fixedly connected to the fixed end anchor plate. Although the above-mentioned installation device can generate vertical prestress on the beam body during construction, the steel strands need to be passed through the separate welded pipe and then the separate welded pipe is fixed. This is relatively complicated in implementation, and it is also inconvenient to disassemble the installation device after pouring concrete. Others have proposed a prestressed box girder tensioning jack-assisted installation and fixing device, including a supporting portal frame, a loading platform fixedly connected between the supporting portal frames, two wheel groove plates symmetrically fixed to the upper ends of the supporting portal frames, two cross beams symmetrically arranged on the upper ends of the wheel groove plates, a jack arranged on the upper ends of the loading platform, a lifting ring arranged on the outer sides of the cross beam, and a hand-pulled electric hoist arranged on the lower ends of the lifting rings; the use of this jack-assisted installation and fixing device can also achieve vertical prestressing of the beam body during construction, but the entire device occupies a large volume and is not convenient to move. Summary of the Invention

[0005] In order to solve one of the above-mentioned technical defects, an embodiment of the present application provides a tensioning bottom wedge for prestressed continuous beams, which can tension the steel strands and quickly unload the tensioning force, and is easy to disassemble.

[0006] According to the first aspect of the embodiment of the present application, a tensioning bottom wedge for pre-stressed continuous beams is provided, which includes, from top to bottom, a lifting ring, a rocker assembly, a wedge seat assembly and a slider assembly; the lifting ring is detachably hinged to the top of the rocker assembly, and the bottom of the rocker assembly passes through the wedge seat assembly and is hinged to the slider assembly; both ends of the slider assembly are connected to the wedge seat assembly.

[0007] Preferably, the slider assembly includes a slider, one end of the slider is provided with a guide shaft, and the other end of the slider is provided with a first screw.

[0008] More preferably, a first guide hole for the guide shaft to pass through is provided on the side of the wedge seat assembly close to the guide shaft; a support block is extended from the end of the wedge seat assembly close to the first screw rod, and a second guide hole for the first screw rod to pass through is provided on the support block; first nuts are provided at both ends of the second guide hole, and the first screw rod is threadedly connected to the two first nuts; the slider assembly slides on the wedge seat assembly through the first guide hole and the second guide hole.

[0009] Preferably, a first through hole is provided on the top of the wedge seat assembly for the rocker assembly to pass through and swing; the inclination direction of the side of the wedge seat assembly close to the slider is consistent with the sliding direction of the slider assembly.

[0010] Preferably, the rocker assembly includes a first suspension rod, a rocker rod is connected below the first suspension rod, and a second suspension rod is connected below the rocker rod; the first suspension rod and the lifting ring are detachably hinged together; the second suspension rod is hinged together with the slider assembly.

[0011] More preferably, the first suspension rod and the suspension ring are hinged together via a first pin; the second suspension rod and the slider assembly are hinged together via a second pin; and the first pin and the second pin are arranged in parallel.

[0012] More preferably, a third through hole for the second pin shaft to pass through is provided on the second hanger rod, and a fourth through hole for the second pin shaft to pass through is provided on the slider assembly; the third through hole is an oblong through hole, and the inner wall of the fourth through hole is adapted to the outer wall of the second pin shaft, so that the second pin shaft can drive the slider assembly to move in the third through hole.

[0013] According to the second aspect of the embodiment of the present application, a bridge-building machine for pre-stressed continuous beams is provided, which is used in conjunction with a steel strand, wherein an anchor end is connected below the steel strand, and a tensioning bottom wedge is detachably connected below the anchor end, and the tensioning bottom wedge is a tensioning bottom wedge as described in any of the above items; the middle part of the rocker arm assembly is arranged in the lower longitudinal beam of the bridge-building machine; a moving assembly is arranged between the wedge seat assembly and the lower longitudinal beam of the bridge-building machine.

[0014] Preferably, two fixed blocks are symmetrically arranged on the wedge seat assembly, and a second through hole is provided on each of the two fixed blocks; the moving assembly includes two second screws, the middle parts of the two second screws respectively pass through the two second through holes, and both ends of the two second screws pass through a support seat; a second nut is provided on one side of each support seat, and the second nut and the second screw are threadedly connected; the support seat is connected to the lower longitudinal beam of the bridge-building machine.

[0015] Preferably, third nuts are provided on both sides of the two second through holes, and the third nuts are threadedly connected to the second screw rods.

[0016] The beneficial technical effects of this application are:

[0017] In this application, the lifting ring is detachably hinged to the top of the rocker assembly, and the bottom of the rocker assembly is hinged to the slider assembly, so that the rocker assembly can swing conveniently, and the rocker assembly can drive the slider assembly to slide on the wedge seat assembly to achieve rapid unloading of the tension force.

[0018] The tensioning bottom wedge provided in this application is suitable for tensioning the steel strands and quickly unloading the tensioning force during the vertical prestressing construction of continuous beams using the pre-tensioning method, and is also easy to disassemble. It solves the problem of damage caused by fine-rolled threaded steel bars without any signs before construction, brittle fracture, a sharp drop in brittle fracture strength after fire, and the occurrence of parent material defects and brittleness and breakage after collision when using the post-tensioning method. It also solves the problems of the existing technology using the pre-tensioning method, such as the complicated implementation process, inconvenient disassembly, and large size that makes it difficult to move. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0020] Figure 1 A schematic structural diagram of a tensioning bottom wedge for pre-tensioned prestressed continuous beams provided in an embodiment of the present application;

[0021] Figure 2A schematic diagram of the connection structure of a slider assembly and a wedge seat assembly for a tensioning bottom wedge of a prestressed continuous beam provided in an embodiment of the present application;

[0022] Figure 3 A schematic structural diagram of a rocker assembly for a tensioning bottom wedge of a prestressed continuous beam provided in an embodiment of the present application;

[0023] Figure 4 A schematic structural diagram of a bridge-building machine for pre-tensioning prestressed continuous beams provided in an embodiment of the present application;

[0024] Figure 5 A schematic diagram of a state of unloading tensioning force of a tensioning bottom wedge for pre-tensioned prestressed continuous beam provided in an embodiment of the present application;

[0025] Figure 6 A schematic structural diagram of a moving assembly of a bridge-building machine for pre-tensioning prestressed continuous beams provided in an embodiment of the present application;

[0026] In the figure: 1 is a lifting ring, 2 is a first pin shaft, 3 is a rocker arm assembly, 4 is a wedge seat assembly, 5 is a slider assembly, 6 is a second pin shaft, 7 is a moving assembly, 8 is a lower longitudinal beam of the bridge-building machine, 9 is a steel strand, 10 is an anchor end, 31 is a first suspension rod, 32 is a rocker arm, 33 is a second suspension rod, 41 is a support block, 42 is a fixed block, 44 is a first through hole, 45 is a first guide hole, 46 is a second guide hole, 51 is a guide shaft, 52 is a first screw rod, 53 is a slider, 71 is a second screw rod, and 72 is a support seat. DETAILED DESCRIPTION

[0027] In order to make the technical solutions and advantages of the embodiments of the present application more clearly understood, the exemplary embodiments of the present application are further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present application, and are not an exhaustive list of all the embodiments. It should be noted that the embodiments and features in the embodiments of the present application can be combined with each other unless they conflict.

[0028] In the process of realizing the present application, the inventors found that providing a tensioning bottom wedge for prestressed continuous beams that can tension the steel strands and quickly unload the tensioning force while being easy to disassemble is an urgent problem that needs to be solved.

[0029] Figure 1 A schematic structural diagram of a tensioning bottom wedge for prestressed continuous beams provided in an embodiment of the present application is shown in FIG. Figure 1As shown, to address the above-mentioned issues, an embodiment of the present application provides a tensioning bottom wedge for prestressed continuous beams. The bottom wedge comprises, from top to bottom, a lifting ring 1, a swing arm assembly 3, a wedge seat assembly 4, and a slider assembly 5. The lifting ring 1 is detachably hinged to the top of the swing arm assembly 3. The bottom of the swing arm assembly 3 passes through the wedge seat assembly 4 and is hinged to the slider assembly 5. Both ends of the slider assembly 5 are connected to the wedge seat assembly 4. Specifically, the swing arm assembly swings in the same plane as the slider assembly slides.

[0030] In this application, the lifting ring is detachably hinged to the top of the rocker assembly, and the bottom of the rocker assembly is hinged to the slider assembly, so that the rocker assembly can swing conveniently, and the rocker assembly can drive the slider assembly to slide on the wedge seat assembly to achieve rapid unloading of the tension force.

[0031] The tensioning bottom wedge provided in this application is suitable for tensioning the steel strands and quickly unloading the tensioning force during the vertical prestressing construction of continuous beams using the pre-tensioning method, and is also easy to disassemble. It solves the problem of damage caused by fine-rolled threaded steel bars without any signs before construction, brittle fracture, a sharp drop in brittle fracture strength after fire, and the occurrence of parent material defects and brittleness and breakage after collision when using the post-tensioning method. It also solves the problems of the existing technology using the pre-tensioning method, such as the complicated implementation process, inconvenient disassembly, and large size that makes it difficult to move.

[0032] Figure 2 A schematic diagram of the connection structure of a slider assembly and a wedge seat assembly for a tensioning bottom wedge of a prestressed continuous beam provided in an embodiment of the present application is shown as follows: Figure 2 As shown, the slider assembly 5 further includes a slider 53, one end of which is provided with a guide shaft 51, and the other end of which is provided with a first screw 52. A first guide hole 45 for the guide shaft 51 is provided on the side of the wedge seat assembly 4 adjacent to the guide shaft 51. A support block 41 extends from the end of the wedge seat assembly 4 adjacent to the first screw 52, and a second guide hole 46 is provided on the support block 41 for the first screw 52. A first nut is provided at each end of the second guide hole 46, and the first screw 52 is threadedly connected to the two first nuts. The slider assembly 5 slides on the wedge seat assembly 4 through the first guide hole 45 and the second guide hole 46. Specifically, the sliding direction of the slider assembly 5 can be at a certain angle to the horizontal direction, specifically an acute angle.

[0033] In the present application, the guide shaft slides within the first guide hole, and the first screw slides within the second guide hole. By providing the first and second guide holes, the sliding direction of the slider relative to the wedge seat assembly can be ensured. The two first nuts can limit the first screw, thereby limiting the position of the slider assembly and the rocker assembly, so that the rocker assembly is initially in a vertical position. When the tensioning force needs to be unloaded, the two first nuts can remove the limit on the first screw, allowing the rocker assembly to drive the slider assembly to slide relative to the wedge seat assembly.

[0034] Furthermore, a first through-hole 44 is provided on the top of the wedge seat assembly 4 for the passage and swinging of the rocker assembly 3. The inclination direction of the side of the wedge seat assembly 4 adjacent to the slider 53 is aligned with the sliding direction of the slider assembly 5. This further ensures that the slider slides in its predetermined sliding direction, i.e., along the side of the wedge seat assembly adjacent to the slider, without deviation, and provides greater precision and stability.

[0035] Figure 3 A structural diagram of a swing arm assembly for a tensioning bottom wedge of a prestressed continuous beam provided in an embodiment of the present application is shown as follows: Figure 3 As shown, the swing arm assembly 3 further includes a first suspension rod 31, a swing arm 32 connected below the first suspension rod 31, and a second suspension rod 33 connected below the swing arm 32. The first suspension rod 31 is detachably hinged to the suspension ring 1, and the second suspension rod 33 is hinged to the slider assembly 5. Specifically, the length of the swing arm 32 is adjustable to meet different length requirements.

[0036] Specifically, the lifting ring 1 and the first suspension rod 31 are hinged together via a first pin 2, enabling the lifting ring to drive the first suspension rod to rotate. The second suspension rod 33 and the slider assembly 5 are hinged together via a second pin 6, enabling the second suspension rod to drive the slider assembly to rotate and slide. More specifically, the first pin 2 and the second pin 6 are arranged parallel to each other, so that the swinging plane of the swing arm assembly and the sliding plane of the sliding assembly are coplanar.

[0037] More specifically, the second suspension rod 33 is provided with a third through-hole for the second pin 6 to pass through, and the slider assembly 5 is provided with a fourth through-hole for the second pin 6 to pass through. The third through-hole is an oblong through-hole, and the inner wall of the fourth through-hole conforms to the outer wall of the second pin 6, allowing the second pin 6 to drive the slider assembly 5 to move within the third through-hole. Specifically, the third through-hole is an oblong through-hole arranged vertically. Because the swing of the rocker arm assembly is arc-shaped, while the displacement of the slider assembly on the wedge seat assembly is linear, by configuring the third through-hole as an oblong through-hole and the inner wall of the fourth through-hole conforming to the outer wall of the second pin, when the arc-shaped swing of the rocker arm assembly is transmitted to the slider assembly, the slider assembly can slide linearly along the side of the wedge seat assembly adjacent to the top surface of the slider.

[0038] Figure 4 This is a schematic diagram of the structure of a bridge-building machine for pre-tensioning prestressed continuous beams provided in an embodiment of the present application. Figure 5 A schematic diagram of a state of unloading tensioning force of a tensioning bottom wedge for prestressed continuous beams provided in an embodiment of the present application is shown as follows: Figure 4 and Figure 5 As shown, the present embodiment also provides a bridge-building machine for prestressing a continuous beam. The machine is used in conjunction with a steel strand 9. An anchor end 10 is connected below the steel strand 9. A tensioning bottom wedge is detachably connected below the anchor end 10. The tensioning bottom wedge is any of the tensioning bottom wedges described above. The middle portion of the rocker assembly 3 is disposed in the lower longitudinal beam 8 of the bridge-building machine. A movable assembly 7 is disposed between the wedge seat assembly 4 and the lower longitudinal beam 8 of the bridge-building machine. Specifically, the anchor end 10 is detachably connected to the lifting ring 1 of the tensioning bottom wedge.

[0039] The tensioning bottom wedge in this application can tension the steel strands and quickly unload the tensioning force after pouring. After unloading the tensioning force, the tensioning bottom wedge can be removed by detaching the anchor section and the lifting ring, allowing construction of the next beam section to proceed. The movable assembly can adjust the relative position between the wedge seat assembly and the lower longitudinal beam of the bridge construction machine, so that the swing arm assembly is in a vertical position in the initial state, which can better tension the steel strands.

[0040] The use of the pre-tensioning method for construction solves the problems that are easily encountered in the existing technology using the post-tensioning method, such as the high-quality rolled threaded steel bars having no signs of damage before they are damaged, being prone to brittle fracture, a sharp drop in brittle fracture strength after being exposed to fire, and the occurrence of base material defects and brittleness and breakage after being bumped.

[0041] Figure 6 A schematic diagram of the structure of a mobile assembly of a bridge-building machine for prestressed continuous beams provided in an embodiment of the present application is shown in FIG. Figure 6 As shown, further, two fixed blocks 42 are symmetrically arranged on the wedge seat assembly 4, and a second through hole is provided on each of the two fixed blocks 42; the moving assembly 7 includes two second screws 71, the middle parts of the two second screws 71 respectively pass through the two second through holes, and both ends of the two second screws 71 pass through a support seat 72; a second nut is provided on one side of each support seat 72, and the second nut and the second screw 71 are threadedly connected; the support seat 72 is connected to the lower longitudinal beam 8 of the bridge-building machine.

[0042] In this application, the support seat is arranged on the lower longitudinal beam of the bridge-building machine, and the second screw rod can be adjusted and limited by the second nut.

[0043] Furthermore, third nuts are provided on both sides of the two second through holes, and are threadedly connected to the second screw rod 71. The third nuts can adjust the position of the fixing block on the second screw rod, so that the swing arm assembly is in a vertical position in the initial state, which can better tension the steel strand.

[0044] Working principle:

[0045] Before pouring concrete, adjust the position of the second nut so that the position of the second screw can be adjusted, and then adjust the position of the third nut so that the fixed block drives the wedge seat assembly to move together, and lock the second nut and the third nut after adjusting to the vertical state of the rocker arm assembly. At this time, the tensioning bottom wedge tensions the steel strand; pour concrete; after the concrete is poured, the rocker arm assembly is still in a vertical state, and the rocker arm assembly has a certain pulling force on the steel strand; the steel strand is consolidated in the beam body, and the limitation of the wedge seat assembly on the slider assembly is eliminated by adjusting the first nut. At this time, the rocker arm assembly drives the slider assembly to slide relative to the wedge seat assembly. After the rocker arm assembly swings, the rocker arm assembly unloads the pulling force on the steel strand, and then disassembles the connection between the lifting ring and the anchor end, disassembles the first pin shaft between the lifting ring and the first hanging rod, and removes the lifting ring; proceed with the construction of the next section of the beam body.

[0046] In the description of this application, it should be understood that the terms "middle", "upper", "lower", "front", "back", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on this application.

[0047] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Thus, a feature specified as "first" or "second" may explicitly or implicitly include one or more of the features. Throughout the description of this application, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0048] In this application, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood broadly. For example, they can refer to fixed connection, detachable connection, or integration; they can refer to direct connection or indirect connection through an intermediary. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0049] Although the preferred embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present application.

[0050] Obviously, those skilled in the art may make various changes and modifications to this application without departing from the spirit and scope of this application. Thus, if these modifications and variations of this application fall within the scope of the claims of this application and their equivalents, this application is intended to include these modifications and variations.

Claims

1. A tensioning bottom wedge for prestressed continuous beams, characterized by: From top to bottom, it includes a lifting ring (1), a swing arm assembly (3), a wedge seat assembly (4) and a slider assembly (5); The lifting ring (1) is detachably hinged to the top of the swing rod assembly (3), and the bottom of the swing rod assembly (3) passes through the wedge seat assembly (4) and is hinged to the slider assembly (5); Both ends of the slider assembly (5) are connected to the wedge seat assembly (4); The slider assembly (5) comprises a slider (53), one end of the slider (53) is provided with a guide shaft (51), and the other end of the slider (53) is provided with a first screw (52); A first guide hole (45) for the guide shaft (51) to pass through is provided on a side of the wedge seat assembly (4) close to the guide shaft (51); A support block (41) extends from one end of the wedge seat assembly (4) close to the first screw rod (52), and a second guide hole (46) for the first screw rod (52) to pass through is provided on the support block (41); Both ends of the second guide hole (46) are provided with a first nut, and the first screw rod (52) is threadedly connected to the two first nuts; The slider assembly (5) slides on the wedge seat assembly (4) through the first guide hole (45) and the second guide hole (46); The inclination direction of the side of the wedge seat assembly (4) close to the slider (53) is consistent with the sliding direction of the slider assembly (5).

2. The tensioning bottom wedge for prestressed continuous beam according to claim 1, characterized in that: A first through hole (44) for the swing rod assembly (3) to pass through and swing is provided on the top of the wedge seat assembly (4).

3. The tensioning bottom wedge for prestressed continuous beam according to claim 1, characterized in that: The swing rod assembly (3) comprises a first suspension rod (31), a swing rod (32) is connected below the first suspension rod (31), and a second suspension rod (33) is connected below the swing rod (32); The first suspension rod (31) and the suspension ring (1) are detachably hinged together; The second suspension rod (33) is hinged to the slider assembly (5).

4. The tensioning bottom wedge for prestressed continuous beam according to claim 3, characterized in that: The first suspension rod (31) and the suspension ring (1) are hinged together via a first pin shaft (2); the second suspension rod (33) and the slider assembly (5) are hinged together via a second pin shaft (6); The first pin shaft (2) and the second pin shaft (6) are arranged in parallel.

5. The tensioning bottom wedge for prestressed continuous beam according to claim 4, characterized in that: The second suspension rod (33) is provided with a third through hole for the second pin shaft (6) to pass through, and the slider assembly (5) is provided with a fourth through hole for the second pin shaft (6) to pass through; The third through hole is an oblong through hole, and the inner wall of the fourth through hole is adapted to the outer wall of the second pin shaft (6), so that the second pin shaft (6) can drive the slider assembly (5) to move in the third through hole.

6. A bridge-building machine for prestressed continuous beams, used in conjunction with a steel strand (9), wherein an anchor end (10) is connected below the steel strand (9), and characterized in that: A tension bottom wedge is detachably connected below the anchor end (10), and the tension bottom wedge is the tension bottom wedge according to any one of claims 1 to 5; The middle portion of the rocker assembly (3) is arranged in the lower longitudinal beam (8) of the bridge-building machine; A moving assembly (7) is provided between the wedge seat assembly (4) and the lower longitudinal beam (8) of the bridge-building machine.

7. The bridge-building machine for pre-tensioned prestressed continuous beams according to claim 6, characterized in that: Two fixing blocks (42) are symmetrically arranged on the wedge seat assembly (4), and both fixing blocks (42) are provided with a second through hole; The moving assembly (7) includes two second screw rods (71), the middle parts of the two second screw rods (71) respectively pass through the two second through holes, and both ends of the two second screw rods (71) pass through support seats (72); a second nut is provided on one side of each support seat (72), and the second nut is threadedly connected to the second screw rod (71); The support seat (72) is connected to the lower longitudinal beam (8) of the bridge-building machine.

8. The bridge-building machine for pre-tensioned prestressed continuous beams according to claim 7, characterized in that: A third nut is provided on both sides of the two second through holes, and the third nut is threadedly connected to the second screw rod (71).

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