A prefabricated box girder expansion joint embedded bar positioning device

Abstract

This invention relates to the field of bridge construction technology and discloses a positioning device for precast box girder expansion joint embedded reinforcement. The device includes two guide rails arranged parallel to each other. Each guide rail has a sliding seat at its top, and each sliding seat has a fixed telescopic column at its top. A rotating seat is rotatably mounted on the top of each telescopic column. A telescopic support beam connects the two rotating seats, and multiple support rods are connected to the bottom of the telescopic support beam. This invention enables precise movement and positioning of the expansion joint embedded reinforcement in four dimensions: longitudinal, angular, vertical, and transverse. It avoids the low installation accuracy of traditional embedded reinforcement processes, which necessitates welding and re-welding or repeated reinforcement correction, thus affecting bridge construction progress. It enables the positioning and installation of precast expansion joint embedded reinforcement in box girders with different skew angles, eliminating the need to weld and fix the precast expansion joint embedded reinforcement to the main reinforcement of the box girder top slab, thus avoiding quality defects such as weld burns and weld beads in the main reinforcement, which affect structural durability and load-bearing capacity.

Description

Technical Field

[0001] This invention relates to the field of bridge construction technology, specifically to a positioning device for pre-embedded reinforcement bars in expansion joints of precast box girders. Background Technology

[0002] To accommodate bridge deck deformation, structural joints, also known as expansion joints, are typically installed between the ends of two beams, between the beam end and the abutment, or at the hinge points of the bridge. These expansion joints prevent the beam from deforming under the influence of environmental temperature, vehicle loads, and its own weight, which could generate internal forces exceeding the structure's inherent resistance and cause cracking and failure. Therefore, the accurate and proper installation of expansion joints is of great significance to the durability of the bridge structure and the safety of traffic.

[0003] Expansion joint construction occurs after the wet joints of the precast box girder and the cast-in-place section at the pier top are completed. Therefore, it is generally necessary to install embedded reinforcement bars on the top slab of the girder at the location of the expansion joint to position and guide the subsequent installation of the bridge deck expansion joint. Currently, during on-site construction, an embedded reinforcement bar for the expansion joint is pre-welded during the binding of the precast box girder reinforcement cage. The embedded reinforcement bar is welded to a transverse reinforcement bar, and the transverse reinforcement bar is directly welded to the main reinforcement bars of the box girder top slab at both ends. This results in weld damage to the main reinforcement bars of the top slab. Due to low welding precision, subsequent repairs and re-welding or correction of the embedded reinforcement bar are required. On the one hand, weld damage to the main reinforcement bars will affect the overall load-bearing capacity and durability of the bridge; on the other hand, repairing and re-installing the embedded reinforcement bar for the expansion joint will affect the overall construction progress.

[0004] Therefore, it is necessary to provide a precast box girder expansion joint pre-embedded reinforcement positioning device to solve the above-mentioned technical problems. Summary of the Invention

[0005] The purpose of this invention is to provide a positioning device for precast box girder expansion joint embedded reinforcement, which has the effect of precise movement and positioning of the expansion joint embedded reinforcement in four dimensions: longitudinal, angular, vertical and lateral.

[0006] The above-mentioned technical objective of the present invention is achieved through the following technical solution: a positioning device for precast box girder expansion joint embedded reinforcement, comprising two guide rails arranged parallel to each other, a sliding seat slidably disposed at the top of each of the two guide rails, a telescopic column fixedly installed at the top of each of the two sliding seats, the length of the telescopic column being adjustable and lockable, a rotating seat rotatably disposed at the top of the telescopic column, a telescopic support beam connected between the two rotating seats, a plurality of support rods connected to the bottom of the telescopic support beam, two parallel fixed plates disposed below the telescopic support beam, the two fixed plates being fixedly connected by a connecting seat, the bottom of the support rods being hinged to the connecting seat, a plurality of slots for placing embedded reinforcement being opened at the bottom of each of the two fixed plates, the slots on the two fixed plates being equidistantly arranged opposite each other, a locking component being disposed between the two fixed plates, the locking component being used to lock the embedded reinforcement fixed in the slots.

[0007] A further configuration of the present invention includes: a plurality of connecting plates disposed between the two fixed plates, the two ends of the connecting plates being fixedly connected to the two fixed plates respectively, a mounting seat being fixedly installed at the top of the connecting plates, the locking assembly including an adjusting rod, the adjusting rod passing through the plurality of mounting seats, a mounting ring being fixedly installed on the adjusting rod, a spring being sleeved on the adjusting rod, one end of the spring being fixedly connected to the mounting ring, the other end of the spring being fixedly connected to the mounting seat, a gripping rod being fixedly installed at one end of the adjusting rod, a plurality of pressure rods being fixedly installed on the side wall of the adjusting rod, the plurality of pressure rods being arranged parallel to each other, when the embedded rib is placed in the slot, the pressure rod presses against the middle of the embedded rib to fix it, and a limiting seat for limiting the pressure rod is disposed between the two fixed plates.

[0008] A further configuration of the present invention is as follows: the telescopic support beam includes a first support beam and a second support beam, the first support beam and the second support beam are slidably connected, one end of the first support beam is fixedly connected to one of the rotating seats, one end of the second support beam is fixedly connected to the other rotating seat, and a fixing rod is detachably connected to both the first support beam and the second support beam, the fixing rod passing through the first support beam or the second support beam, and the bottom end of the fixing rod being fixedly connected to the top end of the support rod.

[0009] A further feature of the present invention is that a telescopic rod is hinged to the middle of the support rod, the length of the telescopic rod is adjustable, and the length can be locked after adjustment, and the bottom end of the telescopic rod is hinged to one side of the connecting seat.

[0010] A further provision of the present invention is as follows: a fixing groove is provided on one side of the card slot; during installation, a pre-embedded rib is placed in the fixing groove; a reinforcing plate is provided at the top of the inner cavity of the fixing groove; the reinforcing plate slides vertically with the fixing groove; a second cylinder is provided on one side of the fixing groove; a second piston is slidably installed in the second cylinder; a second piston rod is fixedly installed at the top of the second piston; the top of the second piston rod is fixedly connected to one side of the reinforcing plate; a second air supply pipe is provided at the bottom of the second cylinder; and an air supply assembly is provided on one side of the limiting seat.

[0011] A further configuration of the present invention is as follows: the air supply assembly includes a first cylinder, the first cylinder being fixedly installed on the side of the limiting seat away from the gripping rod, a first piston being slidably installed inside the first cylinder, a first stopper rod being fixedly installed on one side of the first piston, a tension spring being provided inside the first cylinder, and the side wall of the first piston near the arc-shaped plate being elastically connected to the inner side wall of the first cylinder through the tension spring, a groove being provided on the limiting seat, one end of the first stopper rod extending into the groove, and an arc-shaped plate being fixedly installed at that end, the arc-shaped plate being adapted to the pressure rod, and a first air supply pipe being connected to the side of the first cylinder away from the arc-shaped plate, the first air supply pipe being connected to one end of a second air supply pipe.

[0012] A further configuration of the present invention is that the first gas supply pipe and the second gas supply pipe are embedded and installed inside the fixed plate.

[0013] A further feature of the present invention is that a mounting bracket is installed at the bottom end of each of the two guide rails.

[0014] In summary, the present invention has the following beneficial effects: During positioning, the present invention first transports two guide rails to the construction site and fixes them in the construction position using an installation frame. After fixing multiple embedded bars in the slots, the expansion support beam is moved by a sliding slide, and the height of the expansion support beam is adjusted by an expansion column, so that the fixing plate moves to the expansion joint position. Then, the embedded bars can be welded. The present invention can achieve precise movement and positioning of the expansion joint embedded bars in four dimensions: longitudinal, angular, vertical, and transverse. This avoids the need for broken welds and re-welding or repeated correction of the reinforcing bars due to the low installation accuracy of the embedded bars in traditional processes, which affects the bridge construction progress. It can realize the positioning and installation of the embedded bars of the expansion joints of box girders with different skew angles. It does not require welding and fixing the expansion joint embedded bars to the main reinforcement of the top plate of the box girder, avoiding quality defects such as weld damage and weld beads in the main reinforcement, which affect the structural durability and load-bearing capacity. Attached Figure Description

[0015] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0016] Figure 2 For the present invention Figure 1 A magnified structural diagram at point A;

[0017] Figure 3 For the present invention Figure 1 A magnified structural diagram at point B;

[0018] Figure 4 This is a schematic diagram showing the disassembled structure of the support rod, connecting seat, and telescopic rod of the present invention;

[0019] Figure 5 This is a schematic diagram of the telescopic support beam and fixing rod of the present invention;

[0020] Figure 6 This is a schematic diagram showing the disassembled structure of the fixing plate and adjusting rod of the present invention;

[0021] Figure 7 For the present invention Figure 6 A magnified structural diagram at point C;

[0022] Figure 8 This is a cross-sectional structural diagram of the fixing plate and the first cylinder of the present invention.

[0023] In the diagram: 1. Guide rail; 2. Mounting bracket; 3. Slide seat; 4. Telescopic column; 5. Rotary seat; 6. First support beam; 7. Second support beam; 8. Fixed rod; 9. Support rod; 10. Connecting seat; 11. Telescopic rod; 12. Fixed plate; 1201. Slot; 1202. Fixed slot; 13. Connecting plate; 14. Adjusting rod; 15. Pressure rod; 16. Spring; 17. Handle rod; 18. Mounting ring; 19. Mounting seat; 20. Limiting seat; 21. Embedded rib; 22. First cylinder; 23. First piston; 24. First piston rod; 25. Tension spring; 26. Arc plate; 27. First air supply pipe; 28. Second air supply pipe; 29. ​​Second cylinder; 30. Second piston; 31. Second piston rod; 32. Reinforcing plate. Detailed Implementation

[0024] The present invention will be further described below with reference to the accompanying drawings in the embodiments of the present invention.

[0025] Example 1:

[0026] Please see Figures 1-7In this embodiment of the invention, a positioning device for precast box girder expansion joint embedded reinforcement 21 includes two guide rails 1, which are arranged parallel to each other. Each guide rail 1 has a sliding seat 3 slidably mounted on its top end, and each sliding seat 3 has a telescopic column 4 fixedly mounted on its top end. The length of the telescopic column 4 is adjustable and can be locked. A rotating seat 5 is rotatably mounted on the top end of the telescopic column 4. The rotating seat 5 achieves rotation of the device within a certain range through roller bearings, meeting the installation requirements of the precast reinforcement 21 for skew beam expansion joints and improving the applicability of the device. A telescopic support beam is connected between the two rotating seats 5. Multiple support rods 9 are connected to the bottom end of the telescopic support beam. Two parallel fixed plates 12 are arranged below the telescopic support beam. The two fixed plates 12 are fixedly connected by a connecting seat 10. The bottom end of the support rod 9 is hinged to the connecting seat 10. Multiple slots 1201 for placing the precast reinforcement 21 are provided on the bottom of each of the two fixed plates 12. The slots 1201 are equidistantly arranged opposite each other, and a locking component is provided between the two fixing plates 12. The locking component is used to lock the embedded reinforcing bars 21 fixed in the slots 1201. During positioning, the two guide rails 1 are first transported to the construction site, and the guide rails 1 are fixed in the construction position by the mounting frame 2. After the multiple embedded reinforcing bars 21 are fixed in the slots 1201, the sliding slide 3 drives the telescopic support beam to move, and the height of the telescopic support beam is adjusted by the telescopic column 4, so that the fixing plate 12 moves to the expansion joint position, and then the positioning can be completed. The pre-embedded reinforcement 21 is welded. This invention enables precise movement and positioning of the pre-embedded reinforcement 21 in four dimensions: longitudinal, angular, vertical, and transverse. This avoids the need for broken welds and re-welding or repeated correction of the reinforcement due to the low installation accuracy of the pre-embedded reinforcement 21 in traditional processes, which affects the bridge construction progress. It can realize the positioning and installation of the pre-embedded reinforcement 21 of the box girder expansion joint at different skew angles. There is no need to weld and fix the pre-embedded reinforcement 21 of the expansion joint to the main reinforcement of the box girder top plate, avoiding quality defects such as weld damage and weld beads in the main reinforcement, which affect the structural durability and load-bearing capacity.

[0027] In this embodiment, preferably, a plurality of connecting plates 13 are provided between the two fixed plates 12. The two ends of each connecting plate 13 are fixedly connected to the two fixed plates 12 respectively. A mounting base 19 is fixedly installed at the top of each connecting plate 13. The locking assembly includes an adjusting rod 14 that passes through the plurality of mounting bases 19. A mounting ring 18 is fixedly installed on the adjusting rod 14. A spring 16 is sleeved on the adjusting rod 14. One end of the spring 16 is fixedly connected to the mounting ring 18, and the other end is fixedly connected to the mounting base 19. A gripping rod 17 is fixedly installed at one end of the adjusting rod 14. A plurality of pressure rods 15 are fixedly installed on the side wall of the adjusting rod 14, and the plurality of pressure rods 15 are parallel to each other. In the row setting, when the pre-embedded rib 21 is placed in the slot 1201, the pressure rod 15 presses against the middle of the pre-embedded rib 21 to fix it. A limiting seat 20 for limiting the pressure rod 15 is provided between the two fixing plates 12. When installing the pre-embedded rib 21, the adjusting rod 14 can be stretched and rotated to fix the pressure rod 15 in the position of the limiting seat 20. Then, the pre-embedded ribs 21 are placed one by one on the slot 1201. After the pre-embedded rib 21 is installed, the gripping rod 17 is stretched to make the pressure rod 15 disengage from the limiting seat 20. Then, the adjusting rod 14 is rotated through the gripping rod 17 to make the pressure rod 15 perpendicular to the pre-embedded rib 21. Then, the gripping rod 17 is released. At this time, the spring 16 is still in a compressed state. The reaction force generated by the spring 16 is used to fix the pre-embedded rib 21 in the transverse direction.

[0028] In this embodiment, preferably, each of the two guide rails 1 is equipped with a mounting frame 2 at its bottom end. The mounting frame 2 can fix the guide rail 1 to the bridge. The mounting frame 2 includes two triangular bases, a support top plate, bolts and nuts, etc. The triangular bases are welded to the top of the precast box girder outer formwork column, and the support top plate is welded to the triangular bases.

[0029] In this embodiment, preferably, the telescopic support beam includes a first support beam 6 and a second support beam 7. The first support beam 6 and the second support beam 7 are slidably connected. One end of the first support beam 6 is fixedly connected to one of the rotating seats 5, and one end of the second support beam 7 is fixedly connected to the other rotating seat 5. A fixing rod 8 can be detachably connected to both the first support beam 6 and the second support beam 7. The fixing rod 8 passes through the first support beam 6 or the second support beam 7, and the bottom end of the fixing rod 8 is fixedly connected to the top end of the support rod 9.

[0030] In this embodiment, preferably, a telescopic rod 11 is hinged to the middle of the support rod 9. The length of the telescopic rod 11 is adjustable and can be locked after the length is adjusted. The bottom end of the telescopic rod 11 is hinged to one side of the connecting seat 10. By adjusting the length of the telescopic rod 11, the tilt angle of the telescopic rod 11 can be adjusted, so that the angle of the fixing plate 12 can be adjusted, thereby changing the tilt angle of the pre-embedded reinforcement 21 fixing mechanism, thereby realizing the longitudinal slope adjustment of the pre-embedded reinforcement 21.

[0031] Example 2:

[0032] Because the thickness of the embedded ribs 21 varies, the embedded ribs 21 may not fit perfectly into the slots 1201. The pressure rods 15 can only press and fix the embedded ribs 21 horizontally. The embedded ribs 21 also have some room for movement in the longitudinal direction. Therefore, there is a certain error during installation. When the embedded ribs 21 fit perfectly into the slots 1201, it is still inconvenient to disassemble the fixing plate 12. Furthermore, when the thickness of the embedded ribs 21 varies, some of the pressure rods 15 may not be able to press on the embedded ribs 21, which may cause the embedded ribs 21 to wobble, making subsequent welding work difficult. Therefore, Embodiment 2 was designed.

[0033] Please see Figure 8 In this embodiment of the invention, a fixing groove 1202 is connected to one side of the slot 1201. During installation, a pre-embedded rib 21 is set in the fixing groove 1202. A reinforcing plate 32 is set at the top of the inner cavity of the fixing groove 1202. The reinforcing plate 32 and the fixing groove 1202 slide together vertically. A second cylinder 29 is set on one side of the fixing groove 1202. A second piston 30 is slidably installed in the second cylinder 29. A second stopper rod 31 is fixedly installed at the top of the second piston 30. The top of the second stopper rod 31 is fixedly connected to one side of the reinforcing plate 32. A second air supply pipe 28 is connected to the bottom of the second cylinder 29. An air supply assembly is set on one side of the limiting seat 20.

[0034] In this embodiment, preferably, the air supply assembly includes a first cylinder 22, which is fixedly installed on the side of the limiting seat 20 away from the handle 17. A first piston 23 is slidably installed inside the first cylinder 22, and a first stopper rod 24 is fixedly installed on one side of the first piston 23. A tension spring 25 is provided inside the first cylinder 22. The side wall of the first piston 23 near the arc plate 26 is elastically connected to the inner side wall of the first cylinder 22 through the tension spring 25. A groove is provided on the limiting seat 20, and one end of the first stopper rod 24 extends into the groove and is fixedly installed on the arc plate 26. The arc plate 26 is adapted to the pressure rod 15. A first air supply pipe 27 is connected to the side of the first cylinder 22 away from the arc plate 26. One end of the first air supply pipe 27 is connected to one end of the second air supply pipe 28. The first air supply pipe 27 and the second air supply pipe 28 are embedded in the inside of the fixing plate 12.

[0035] During installation, first pull the lever 17 and rotate the pressure rod 15 until it contacts the arc plate 26. Then release the lever 17. Under the elastic force of the spring 16, the pressure rod 15 moves toward the limiting seat 20 and enters the groove on the limiting seat 20. When the pressure rod 15 moves, it drives the first stop rod 24 to move through the arc plate 26, thereby driving the first piston 23 to move to the left. This allows the gas in the first cylinder 22 to enter the second cylinder 29 through the first air supply pipe 27 and the second air supply pipe 28, thereby pushing the second piston 30 to... When the second piston 30 moves upward, it drives the reinforcing plate 32 upward via the second piston rod 31, so that the reinforcing plate 32 moves to contact the top inner wall of the fixing groove 1202. Then, the embedded rib 21 can be moved into the fixing groove 1202. After all the embedded ribs 21 are installed, stretch the gripping rod 17 to disengage the pressure rod 15 from the arc plate 26. Then, rotate the adjusting rod 14 by gripping the rod 17 to make the pressure rod 15 perpendicular to the embedded rib 21. Release the gripping rod 17. At this time, the spring 16 is still in a compressed state. The spring 16 generates a reaction force to fix the embedded rib 21 in the transverse direction. Simultaneously, after the pressure rod 15 separates from the arc-shaped plate 26, under the tension of the tension spring 25, the first piston 23 moves to the right. This allows gas in the second cylinder 29 to enter the first cylinder 22 through the second air supply pipe 28 and the first air supply pipe 27, causing the second piston 30 to move downwards. As the second piston 30 moves downwards, it drives the reinforcing plate 32 downwards via the second piston rod 31, pressing the reinforcing plate 32 against the top wall of the embedded rib 21. This design secures the embedded ribs 21 vertically, improving their stability. The structure allows for automatic locking of the embedded ribs 21 vertically when the pressure rod 15 is moved out of the limiting seat 20, eliminating the need for further operation and making it convenient. Furthermore, the pneumatic transmission ensures that even with variations in the thickness of the embedded ribs 21, the reinforcing plate 32 can press against each rib, thus better securing each one.

[0036] The above description is only a preferred embodiment of the present invention. Therefore, all equivalent changes or modifications made to the structure, features and principles described in the claims of this patent application are included in the scope of this patent application.

Claims

1. A prefabricated box girder expansion joint embedded bar positioning device, comprising two guide rails (1), the two guide rails (1) are arranged parallel to each other, characterized in that: The top end of two guide rails (1) is slidably provided with a sliding seat (3), the top end of two sliding seats (3) is fixedly installed with a telescopic column (4), the top end of the telescopic column (4) is rotatably installed with a rotating seat (5), a telescopic support beam is connected between two rotating seats (5), the bottom end of the telescopic support beam is connected with a plurality of support rods (9), two fixed plates (12) are arranged below the telescopic support beam and are arranged in parallel with each other, two fixed plates (12) are fixedly connected through a connecting seat (10), the bottom end of the support rod (9) is hinged to the connecting seat (10), a plurality of clamping grooves (1201) for placing pre-buried ribs (21) are formed in the bottom of two fixed plates (12), a locking assembly is arranged between two fixed plates (12), and the locking assembly is used for locking the pre-buried rib (21) fixed in the clamping groove (1201); A plurality of connecting plates (13) are arranged between two fixed plates (12), both ends of the connecting plate (13) are fixedly connected with two fixed plates (12), the top end of the connecting plate (13) is fixedly installed with a mounting seat (19), the locking assembly comprises an adjusting rod (14), the adjusting rod (14) penetrates a plurality of mounting seats (19), the adjusting rod (14) is fixedly installed with a mounting ring (18), the adjusting rod (14) is sleeved with a spring (16), one end of the spring (16) is fixedly connected with the mounting ring (18), the other end of the spring (16) is fixedly connected with the mounting seat (19), one end of the adjusting rod (14) is fixedly installed with a handle rod (17), a plurality of pressing rods (15) are fixedly installed on the side wall of the adjusting rod (14), and the plurality of pressing rods (15) are arranged in parallel with each other; when the pre-buried rib (21) is placed in the clamping groove (1201), the pressing rod (15) is pressed on the middle part of the pre-buried rib (21) to fix it, and a limiting seat (20) for limiting the pressing rod (15) is arranged between two fixed plates (12); One side of the clamping groove (1201) is communicated with a fixed groove (1202), the top of the inner cavity of the fixed groove (1202) is provided with a reinforcing plate (32), the reinforcing plate (32) is slidably matched with the fixed groove (1202) in an up-down direction, one side of the fixed groove (1202) is provided with a second cylinder (29), the second cylinder (29) is slidably installed with a second piston (30), the top end of the second piston (30) is fixedly installed with a second plug rod (31), the top end of the second plug rod (31) is fixedly connected with one side of the reinforcing plate (32), the bottom of the second cylinder (29) is communicated with a second gas conveying pipe (28), and one side of the limiting seat (20) is provided with a gas conveying assembly.

2. The positioning device for precast box girder expansion joint embedded bar according to claim 1, characterized in that: The telescopic support beam comprises a first support beam (6) and a second support beam (7), the first support beam (6) is in sliding connection with the second support beam (7), one end of the first support beam (6) is fixedly connected with one of the rotating seats (5), one end of the second support beam (7) is fixedly connected with the other rotating seat (5), and the first support beam (6) and the second support beam (7) are detachably connected with the fixing rods (8), and the bottom end of the fixing rod (8) is fixedly connected with the top end of the support rod (9).

3. The positioning device for precast box girder expansion joint embedded bar according to claim 2, characterized in that: The middle part of the support rod (9) is hingedly connected with the telescopic rod (11), and the bottom end of the telescopic rod (11) is hingedly connected with one side of the connecting seat (10).

4. The positioning device for precast box girder expansion joint embedded bar according to claim 1, characterized in that: The gas conveying assembly comprises a first cylinder (22), the first cylinder (22) is fixedly installed on one side of the limiting seat (20) away from the handle bar (17), a first piston (23) is slidably installed in the first cylinder (22), a first plug rod (24) is fixedly installed on one side of the first piston (23), a tension spring (25) is arranged in the first cylinder (22), the side wall of the first piston (23) close to the arc-shaped plate (26) is elastically connected with the inner side wall of the first cylinder (22) through the tension spring (25), a groove is formed in the limiting seat (20), one end of the first plug rod (24) extends into the groove, and an arc-shaped plate (26) is fixedly installed at the end, the arc-shaped plate (26) is matched with the pressing rod (15), and a first gas conveying pipe (27) is arranged on the side of the first cylinder (22) away from the arc-shaped plate (26) and is in communication.

5. The positioning device for precast box girder expansion joint embedded bar according to claim 4, characterized in that: The first gas conveying pipe (27) and the second gas conveying pipe (28) are embeddedly installed in the inside of the fixing plate (12).

6. The positioning device for precast box girder expansion joint embedded bar according to claim 1, characterized in that: The bottom end of each of the two guide rails (1) is provided with a mounting rack (2).

Images