A precast pedestal for post-tensioned prestressed box girders of reinforced concrete

Abstract

The present invention discloses a precast pedestal for post-tensioned prestressed concrete box girders, which relates to the field of concrete box girders and includes a table board, a pedestal board, pedestal ends, a fixed cross beam and a movable cross beam. The table board is located between two pedestal boards, and the pedestal ends are integrally formed at both ends of the pedestal board. The fixed cross beam is fixedly installed on one side of the pedestal end. In the precast pedestal for post-tensioned prestressed concrete box girders of the present invention, a cutting knife plate is integrated in the fixed cross beam and located below the prestressed tendon, eliminating the trouble of using an external cutting machine for cutting. The force applied by the jack is utilized to cut the prestressed tendon, making it more labor-saving and convenient to cut the prestressed tendon. To push the template to change its position and adjust the position of the template, the lifting connecting frame then drives the template clamping plate and the template to rise, separating the template from the solidified concrete, eliminating the trouble of manually lifting the template for separation.

Description

Technical Field

[0001] The present invention relates to the field of concrete box girders, and particularly to a precast pedestal for a reinforced concrete post-tensioned prestressed box girder. Background Art

[0002] A precast pedestal for a reinforced concrete post-tensioned prestressed box girder is a precast pedestal that uses the post-tensioning method to produce prestressed box girders. When precasting and pouring a prestressed box girder, cement concrete is first poured, and after reaching more than 75% of the designed strength, prestressing tendons are then tensioned to form a prestressed concrete box girder. It is an indispensable component in the precast production of prestressed box girders;

[0003] Chinese Patent with the publication number "CN110843124A" discloses "a pedestal suitable for post-tensioned precast box girders, which includes a main pedestal and end pedestals provided at both ends of the main pedestal. The main pedestal and the end pedestals are both placed on a concrete foundation; the end pedestal includes an inner end pedestal and an outer end pedestal". Although it can achieve the effect that "before tensioning the prestressed steel strands of the box girder body of the present invention, the connecting member that fixedly connects the inner end pedestal and the outer end pedestal is removed, and the sealed anchor end of the box girder is in a suspended state and does not receive the reaction force generated by the upward arch of the beam body, thereby ensuring that the relatively weak sealed anchor end of the entire beam body will not undergo shear failure", when the precast pedestal is in use, after the box girder is precast, the pedestal cannot cut the prestressing tendons, and external tools are required to cut the prestressing tendons. Moreover, the position is narrow and the operation is troublesome when cutting the prestressing tendons, which is not convenient for the cutting and use of the prestressing tendons after the box girder is precast. Also, when installing the formwork, the formwork has a certain weight, and it is laborious to adjust the position after installation, which is not convenient for the adjustment and use during the pouring of the box girder. At the same time, after the concrete is tightened, the formwork will adhere to the outside of the box girder. Therefore, when lifting the formwork to separate it from the box girder, the operation is more laborious, which is not convenient for the separation and use of the formwork and the box girder. Summary of the Invention

[0004] The main purpose of the present invention is to provide a precast pedestal for a reinforced concrete post-tensioned prestressed box girder, which can effectively solve the technical problems raised in the background art.

[0005] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0006] A post-tensioned prestressed box girder precast pedestal for reinforced concrete, comprising a table board, a pedestal board, pedestal ends, a fixed cross beam and a movable cross beam. The table board is located between two pedestal boards. The pedestal ends are integrally formed at both ends of the pedestal board. The fixed cross beam is fixedly installed on one side of the pedestal end. The movable cross beam is located on one side of the fixed cross beam. Rotating mounting seats are movably installed in front of and behind the interior of the fixed cross beam. A jack is fixedly installed on the outer side of the rotating mounting seat. An anchor plate structure is fixedly installed on one side of the movable cross beam. A first lifting strut is fixedly installed at the upper end of the pedestal end. A second lifting strut is fixedly installed at the upper end of the fixed cross beam. A lifting and cutting structure is arranged on the outer sides of the first lifting strut and the second lifting strut. A lifting card slot is opened on the inner side of the fixed cross beam. A template positioning structure is fixedly installed at the upper end of the pedestal end on one side of the first lifting strut.

[0007] As a further solution of the present invention, two positioning sleeves are fixedly installed on the other side of the movable cross beam. When the jack is horizontal, it abuts against the other side of the movable cross beam and fits with the positioning sleeve.

[0008] As a further solution of the present invention, a positioning plate is fixedly installed on one side of the fixed cross beam. A plurality of perforated sleeves are embedded on one side of the positioning plate. A plurality of prestressing tendons penetrate through the two fixed cross beams. The prestressing tendons pass through the perforated sleeves and are located above the table board.

[0009] As a further solution of the present invention, the two sides of the table board are parallel to the side surfaces of the pedestal ends. The two fixed cross beams are fixedly connected to the two sides of the table board.

[0010] As a further solution of the present invention, the anchor plate structure includes a fixed anchor plate, a steel bar anchor sleeve and a steel bar clip. The fixed anchor plate is fixedly installed on one side of the movable cross beam. A plurality of steel bar anchor sleeves are inserted into one side of the movable cross beam. The steel bar clips are inserted into the steel bar anchor sleeves. The steel bar anchor sleeves are arranged in parallel with the perforated sleeves.

[0011] As a further solution of the present invention, a through hole communicating with the steel bar anchor sleeve is opened in the interior of the movable cross beam. The prestressing tendon passes through the steel bar anchor sleeve, the steel bar clip and the through hole in the movable cross beam.

[0012] As a further solution of the present invention, the lifting and cutting structure includes a first lifting sleeve rod, a lifting plate, a connecting rod, a splitting cutter plate and a triangular cutting edge. A plurality of first lifting sleeve rods are movably sleeved on the outer sides of the first lifting strut and the second lifting strut. The lifting plate is fixedly installed on the outer sides of the plurality of first lifting sleeve rods. A plurality of connecting rods are fixedly installed at the lower end of the lifting plate. The splitting cutter plate is fixedly installed at the lower end of the connecting rod. The triangular cutting edge is opened on the top surface of the splitting cutter plate. The prestressing tendon is located above the splitting cutter plate.

[0013] As a further solution of the present invention, both sides of the slitting cutter plate are inserted into the lifting slot. The slitting cutter plate is located above the table top plate and is triangularly arranged. The prestressed tendon is located in the bottom groove of the slitting cutter plate, and when the jack is vertical, it abuts against the lower end of the lifting plate.

[0014] As a further solution of the present invention, the template positioning structure includes a third lifting strut, a second lifting sleeve rod, a lifting connecting frame, a template clamping plate and an adjusting screw. The third lifting strut is fixedly installed at the upper end of the end of the pedestal and is located on one side of the first lifting strut. The second lifting sleeve rod is movably sleeved outside the third lifting strut. The lifting connecting frame is fixedly installed at one end of the second lifting sleeve rod, and the lifting plate is located below the lifting connecting frame. The template clamping plate is fixedly installed at one end of the lifting connecting frame, and a plurality of adjusting screws are threadedly installed on the frame of the template clamping plate.

[0015] As a further solution of the present invention, the template clamping plate is located above the table top plate. The adjusting screw penetrates through the template clamping plate, and the top of the lifting connecting frame is stuck on the upper end of the lifting plate, and the lifting plate drives the lifting connecting frame to rise and move.

[0016] Compared with the prior art, the present invention has the following beneficial effects: The slitting cutter plate is integrated in the fixed cross beam and is located below the prestressed tendon. When the prestressed tendon needs to be cut, the slitting cutter plate is lifted by pulling the lifting plate, and the triangular cutting edge is moved upward to contact the prestressed tendon for cutting, saving the trouble of using an external cutting machine for cutting;

[0017] When cutting the prestressed tendon, the jack is rotated to be vertical by using the rotation of the rotating mounting seat, so that the jack abuts against the lower end of the lifting plate. Therefore, when the jack exerts force, it pushes the lifting plate and the slitting cutter plate upward, and then makes the triangular cutting edge move upward to contact the prestressed tendon and cut the prestressed tendon. The force of the jack is used to cut the prestressed tendon, making it more labor-saving and convenient to cut the prestressed tendon;

[0018] When the position of the template needs to be adjusted, when the template is installed on the table top plate, the template is located inside the template clamping plates on both sides. By rotating the adjusting screw to make it abut against the outside of the template, and then using the rotation of the adjusting screw to push out, the template is pushed to change its position for adjusting the position of the template, which is more convenient for adjusting the position of the template;

[0019] When the template needs to be removed, the top of the lifting connecting frame is stuck on the upper end of the lifting plate, and at the same time, a plurality of adjusting screws are screwed out to be tightly connected with the template, so that the template clamping plate is fixed to the template. Therefore, when the lifting plate rises, it also drives the lifting connecting frame to rise and move, and the lifting connecting frame drives the template clamping plate and the template to rise, so that the template is separated from the solidified concrete, saving the trouble of manually lifting the template for separation, and being more convenient for separating the template from the box girder. Description of the Drawings

[0020] Figure 1 This is the overall structural schematic diagram of a precast pedestal for a post-tensioned prestressed box girder of reinforced concrete in the present invention;

[0021] Figure 2 This is the structural diagram after the installation of prestressing tendons in a precast pedestal for a post-tensioned prestressed box girder of reinforced concrete in the present invention;

[0022] Figure 3 This is the partial structural diagram of a precast pedestal for a post-tensioned prestressed box girder of reinforced concrete in the present invention;

[0023] Figure 4 This is the partial structural diagram of the vertical jack in a precast pedestal for a post-tensioned prestressed box girder of reinforced concrete in the present invention;

[0024] Figure 5 This is the partial side structural diagram of a precast pedestal for a post-tensioned prestressed box girder of reinforced concrete in the present invention;

[0025] Figure 6 This is the partial structural diagram of the template positioning structure in a precast pedestal for a post-tensioned prestressed box girder of reinforced concrete in the present invention;

[0026] Figure 7 This is the partial structural diagram of the fixed crossbeam in a precast pedestal for a post-tensioned prestressed box girder of reinforced concrete in the present invention;

[0027] Figure 8 This is the partial structural diagram of the lifting and cutting structure in a precast pedestal for a post-tensioned prestressed box girder of reinforced concrete in the present invention.

[0028] In the figure: 1, table board; 2, pedestal board; 3, pedestal end; 4, fixed crossbeam; 5, positioning plate; 6, rotary mounting seat; 7, jack; 8, movable crossbeam; 9, positioning sleeve; 10, anchor plate structure; 11, fixed anchor plate; 12, steel bar anchor sleeve; 13, steel bar clamping piece; 14, first lifting strut; 15, second lifting strut; 16, lifting and cutting structure; 17, first lifting sleeve rod; 18, lifting plate; 19, connecting rod; 20, splitting knife plate; 21, triangular cutting edge; 22, lifting card slot; 23, template positioning structure; 24, third lifting strut; 25, second lifting sleeve rod; 26, lifting connecting frame; 27, template clamping plate; 28, adjusting screw; 29, prestressing tendon; 30, perforated sleeve. Specific embodiments

[0029] In order to make the technical means, creative features, achieved purposes and effects of the present invention easy to understand, the present invention will be further described below in conjunction with specific embodiments.

[0030] As Figures 1 - 8As shown in the figure, a precast pedestal for post-tensioned prestressed box girders made of reinforced concrete includes a deck slab 1, pedestal slabs 2, pedestal ends 3, a fixed crossbeam 4, and a movable crossbeam 8. The deck slab 1 is located between two pedestal slabs 2. The pedestal ends 3 are integrally formed at both ends of the pedestal slabs 2. The fixed crossbeam 4 is fixedly installed on one side of the pedestal ends 3. The movable crossbeam 8 is located on one side of the fixed crossbeam 4. Rotary mounting seats 6 are movably installed in the front and rear of the fixed crossbeam 4. Jacks 7 are fixedly installed on the outer sides of the rotary mounting seats 6. An anchor plate structure 10 is fixedly installed on one side of the movable crossbeam 8. A first lifting strut 14 is fixedly installed at the upper end of the pedestal ends 3. A second lifting strut 15 is fixedly installed at the upper end of the fixed crossbeam 4. A lifting cutting structure 16 is arranged on the outer sides of the first lifting strut 14 and the second lifting strut 15. A lifting slot 22 is opened on the inner side of the fixed crossbeam 4. A template positioning structure 23 is fixedly installed on the upper end of the pedestal ends 3 on one side of the first lifting strut 14.

[0031] In this embodiment, two positioning sleeves 9 are fixedly installed on the other side of the movable crossbeam 8. When the jack 7 is horizontal, it abuts against the other side of the movable crossbeam 8 and fits with the positioning sleeve 9, and the positioning sleeve 9 plays an effect of positioning and placing in a parallel state.

[0032] As a further scheme of the present invention, a positioning plate 5 is fixedly installed on one side of the fixed crossbeam 4. A plurality of perforated sleeves 30 are embedded on one side of the positioning plate 5. A plurality of prestressed tendons 29 pass through the two fixed crossbeams 4 on both sides. The prestressed tendons 29 pass through the perforated sleeves 30. The prestressed tendons 29 are located above the deck slab 1. The prestressed tendons 29 are components of the box girder and are also the tensioning parts of the post-tensioned prestress.

[0033] As a further scheme of the present invention, the two sides of the deck slab 1 are parallel to the side surfaces of the pedestal ends 3. The two fixed crossbeams 4 on both sides are fixedly connected to the two sides of the deck slab 1, and the fixed crossbeams 4 play an effect of tightly positioning the deck slab 1 and the pedestal ends 3.

[0034] As a further scheme of the present invention, the anchor plate structure 10 includes a fixed anchor plate 11, a steel bar anchor sleeve 12, and a steel bar clip 13. The fixed anchor plate 11 is fixedly installed on one side of the movable crossbeam 8. A plurality of steel bar anchor sleeves 12 are inserted into one side of the movable crossbeam 8. The steel bar clips 13 are inserted into the steel bar anchor sleeves 12. The steel bar anchor sleeves 12 are arranged in parallel with the perforated sleeves 30. The steel bar anchor sleeves 12 and the steel bar clips 13 form an anchor.

[0035] As a further scheme of the present invention, a through hole communicating with the steel bar anchor sleeve 12 is opened in the movable crossbeam 8. The prestressed tendon 29 passes through the steel bar anchor sleeve 12, the steel bar clip 13, and the through hole in the movable crossbeam 8. The prestressed tendon 29 is clamped and fixed by the contraction of the steel bar clip 13 in the steel bar anchor sleeve 12, so that the prestressed tendon 29 is anchored on the fixed anchor plate 11.

[0036] As a further solution of the present invention, the ascending cutting structure 16 includes a first lifting sleeve rod 17, a lifting plate 18, a connecting rod 19, a cutting knife plate 20 and a triangular cutting edge 21. A plurality of first lifting sleeve rods 17 are movably sleeved outside the first lifting support rod 14 and the second lifting support rod 15. The lifting plate 18 is fixedly installed outside the plurality of first lifting sleeve rods 17. A plurality of connecting rods 19 are fixedly installed at the lower end of the lifting plate 18. The cutting knife plate 20 is fixedly installed at the lower end of the connecting rod 19. The triangular cutting edge 21 is formed on the top surface of the cutting knife plate 20. The prestressed tendon 29 is located above the cutting knife plate 20, and the prestressed tendon 29 does not come into contact with the cutting knife plate 20 during tensioning.

[0037] As a further solution of the present invention, both sides of the cutting knife plate 20 are inserted into the lifting card slots 22. The lifting card slots 22 play a role in positioning the lifting of the cutting knife plate 20. The cutting knife plate 20 is located above the table top plate 1. The cutting knife plate 20 is triangularly arranged. Through this triangular arrangement, it can contact the prestressed tendon 29 to the greatest extent and move to cut it. The prestressed tendon 29 is located in the bottom groove of the cutting knife plate 20. When the jack 7 is vertical, it abuts against the lower end of the lifting plate 18.

[0038] As a further solution of the present invention, the template positioning structure 23 includes a third lifting support rod 24, a second lifting sleeve rod 25, a lifting connection frame 26, a template clamping plate 27 and an adjusting screw 28. The third lifting support rod 24 is fixedly installed at the upper end of the pedestal end 3 and is located on one side of the first lifting support rod 14. The second lifting sleeve rod 25 is movably sleeved outside the third lifting support rod 24. The lifting connection frame 26 is fixedly installed at one end of the second lifting sleeve rod 25, and the lifting plate 18 is located below the lifting connection frame 26. The template clamping plate 27 is fixedly installed at one end of the lifting connection frame 26. A plurality of adjusting screws 28 are threadedly installed on the frame of the template clamping plate 27.

[0039] As a further solution of the present invention, the template clamping plate 27 is located above the table top plate 1. The adjusting screw 28 penetrates through the template clamping plate 27. The top of the lifting connection frame 26 is stuck on the upper end of the lifting plate 18. The lifting plate 18 drives the lifting connection frame 26 to rise and move. The adjusting screw 28 plays a role in pushing and clamping the template.

[0040] It should be noted that the present invention is a precast pedestal for post-tensioned prestressed box girders of reinforced concrete. When in use, a release paint is brushed on the table board 1, and the steel bar framework of the box girder is laid. Then, the prestressed steel bars 29 are passed through the fixed cross beam 4 and the movable cross beam 8, so that the prestressed steel bars 29 penetrate into the steel bar framework. At the same time, the prestressed steel bars 29 are connected to the steel bar anchor sleeves 12 and the steel bar wedge plates 13 for fixation, so that both sides of the prestressed steel bars 29 are fixedly connected to the movable cross beam 8 and the fixed anchor plate 11. The fixed core mold and the formwork of the box girder are installed on the table board 1. Finally, concrete is poured into the formwork on the table board 1. After the concrete reaches more than 75% of the designed strength, the movable cross beam 8 is pushed to move to one side by the jack 7, so as to tension the prestressed steel bars 29 and reach the prestress value. After the concrete solidifies, the formwork is removed, and the exposed prestressed steel bars 29 on both sides are cut off, thus completing the precast of the prestressed box girder;

[0041] When it is necessary to cut off the exposed prestressed steel bars 29 on both sides, the jack 7 is rotated vertically by using the rotation of the rotary mounting base 6, so that the jack 7 abuts against the lower end of the lifting plate 18. Therefore, when the jack 7 exerts force, the lifting plate 18 is pushed to move upward. The lifting plate 18 then drives the splitting cutter plate 20 to move upward through the connecting rod 19, and further makes the triangular cutting edge 21 move upward to contact the prestressed steel bars 29 and cut off the prestressed steel bars 29;

[0042] When it is necessary to adjust the installation position of the formwork, when the formwork is installed on the table board 1, the formwork is located within the formwork clamping plates 27 on both sides. By rotating the adjusting screw rod 28, it abuts against the outside of the formwork, and then the formwork is pushed to change its position by using the rotation and ejection of the adjusting screw rod 28 to adjust the position of the formwork;

[0043] When it is necessary to remove the formwork, the top of the lifting connecting frame 26 is stuck on the upper end of the lifting plate 18. At the same time, a plurality of adjusting screw rods 28 are screwed out and clamped and connected to the formwork, so that the formwork clamping plates 27 are fixed to the formwork. Therefore, when the lifting plate 18 rises, it also drives the lifting connecting frame 26 to rise and move. The lifting connecting frame 26 then drives the formwork clamping plates 27 and the formwork to rise, so that the formwork is separated from the solidified concrete.

[0044] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. A precast pedestal for post-tensioned prestressed box girders of reinforced concrete, comprising a table board, pedestal boards, pedestal ends, a fixed cross beam and a movable cross beam. The table board is located between two pedestal boards. The pedestal ends are integrally formed at both ends of the pedestal boards. The fixed cross beam is fixedly installed on one side of the pedestal ends. The movable cross beam is located on one side of the fixed cross beam, characterized in that: Rotary mounting seats are movably installed at both the front and rear inside the fixed crossbeam. Jacks are fixedly installed on the outer sides of the rotary mounting seats. An anchor plate structure is fixedly installed on one side of the movable crossbeam. A first lifting strut is fixedly installed at the upper end of the pedestal end. A second lifting strut is fixedly installed at the upper end of the fixed crossbeam. A lifting and cutting structure is arranged outside the first lifting strut and the second lifting strut. A lifting slot is opened inside the fixed crossbeam. A template positioning structure is fixedly installed on the upper end of the pedestal end on one side of the first lifting strut. Two positioning sleeves are fixedly installed on the other side of the movable crossbeam. When the jack is horizontal, it abuts against the other side of the movable crossbeam and fits with the positioning sleeves. A positioning plate is fixedly installed on one side of the fixed crossbeam. A plurality of perforated sleeves are embedded on one side of the positioning plate. A plurality of prestressed tendons pass through the two fixed crossbeams. The prestressed tendons pass through the perforated sleeves and are located above the table board. The lifting and cutting structure includes a first lifting sleeve rod, a lifting plate, a connecting rod, a cutting knife plate and a triangular cutting edge. A plurality of first lifting sleeve rods are movably sleeved outside the first lifting strut and the second lifting strut. The lifting plate is fixedly installed on the outer sides of the plurality of first lifting sleeve rods. A plurality of connecting rods are fixedly installed at the lower end of the lifting plate. The cutting knife plate is fixedly installed at the lower end of the connecting rod. The triangular cutting edge is opened on the top surface of the cutting knife plate. The prestressed tendons are located above the cutting knife plate. Both sides of the cutting knife plate are inserted into the lifting slot. The cutting knife plate is located above the table board. The cutting knife plate is triangularly arranged. The prestressed tendons are located in the bottom groove of the cutting knife plate. When the jack is vertical, it abuts against the lower end of the lifting plate.

2. A precast pedestal for post-tensioned prestressed box girders of reinforced concrete according to claim 1, characterized in that: Both sides of the table board are parallel to the side surfaces of the pedestal end. The two fixed crossbeams are fixedly connected to both sides of the table board.

3. A precast pedestal for post-tensioned prestressed box girders of reinforced concrete according to claim 1, characterized in that: The anchor plate structure includes a fixed anchor plate, a steel bar anchor sleeve and a steel bar clip. The fixed anchor plate is fixedly installed on one side of the movable crossbeam. A plurality of steel bar anchor sleeves are inserted into one side of the movable crossbeam. The steel bar clips are inserted into the steel bar anchor sleeves. The steel bar anchor sleeves and the perforated sleeves are arranged in parallel.

4. A precast pedestal for post-tensioned prestressed box girders of reinforced concrete according to claim 3, characterized in that: A through hole communicating with the steel bar anchor sleeve is opened inside the movable crossbeam. The prestressed tendons pass through the steel bar anchor sleeves, the steel bar clips and the through hole inside the movable crossbeam.

5. A precast pedestal for a post-tensioned prestressed box girder of reinforced concrete according to claim 1, characterized in that: The template positioning structure includes a third lifting strut, a second lifting sleeve rod, a lifting connecting frame, a template clamping plate and an adjusting screw. The third lifting strut is fixedly installed at the upper end of the pedestal end and is located on one side of the first lifting strut. The second lifting sleeve rod is movably sleeved outside the third lifting strut. The lifting connecting frame is fixedly installed at one end of the second lifting sleeve rod. And the lifting plate is located below the lifting connecting frame. The template clamping plate is fixedly installed at one end of the lifting connecting frame. A plurality of adjusting screws are threadedly installed on the frame of the template clamping plate.

6. A precast pedestal for post-tensioned prestressed box girders of reinforced concrete according to claim 5, characterized in that: The template clamping plate is located above the table board. The adjusting screws penetrate through the template clamping plate. The top of the lifting connecting frame is stuck on the upper end of the lifting plate. The lifting plate drives the lifting connecting frame to rise and move.

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