Anti-floating device for prefabricated box girder inner mold

Abstract

The application provides a precast box girder inner mold anti-floating device, which comprises a transverse compression rod, a supporting and jacking rod, a through pin, a lifting ring and a basket bolt. The supporting and jacking rod is connected to the two sides of the transverse compression rod, and the bottom of the supporting and jacking rod extends out of the bottom of the transverse compression rod. The through pin is arranged at the two ends of the transverse compression rod. The lifting ring is connected to the top horizontal rib of the box girder side mold. The two ends of the basket bolt are connected to the through pin and the lifting ring respectively, and the transverse compression rod acts on the box girder inner mold through the supporting and jacking rod by tightening the basket bolt. Through the main body of the transverse compression rod, the basket bolt is connected with the box girder side mold, the transverse compression rod is fastened by tightening the basket bolt, and the supporting and jacking rod supports on the box girder inner mold, so that the problem of the inner mold floating up in the precast box girder concrete pouring process is solved.

Description

Technical Field

[0001] This application relates to the field of precast box girder technology for bridge engineering, and in particular to an anti-buoyancy device for the inner mold of a precast box girder. Background Technology

[0002] In bridge construction, the quality of precast box girders plays a crucial role in the stability and durability of the entire bridge structure. The stability of the inner mold directly affects the dimensional accuracy of the box girder structure and the pass rate of the concrete protective layer. The concrete pouring process for precast box girders requires the use of anti-buoyancy devices to suppress the floating of the inner mold during the pouring process, ensuring that the internal structural strength and appearance quality of the box girder meet the engineering requirements.

[0003] In existing technologies, the anti-floating device for the inner formwork of precast box girders uses a structure in which pressure bars and tie rods act on the top slab. This structure relies on manual operation for positioning and reinforcement, and requires tie rods and pressure bars to be arranged on the top slab to form a constraint system.

[0004] However, the above-mentioned technical solutions are difficult to effectively control the displacement of the inner formwork during the concrete pouring process. In particular, when pouring the bottom slab, the inner formwork is prone to float due to the impact and buoyancy of the concrete, resulting in out-of-tolerance dimensions of the box girder web and increased deviation in the thickness of the concrete cover between the top and bottom slabs, which in turn leads to concrete misalignment and appearance quality defects. Utility Model Content

[0005] This application provides an anti-buoyancy device for the inner formwork of a precast box girder to solve the problem of the inner formwork floating during the concrete pouring process of the precast box girder.

[0006] This application provides an anti-buoyancy device for the inner formwork of a precast box girder, comprising:

[0007] Lateral pressure bar;

[0008] A support rod is connected to both sides of the transverse pressure bar, and the bottom of the support rod extends out of the bottom of the transverse pressure bar;

[0009] Through pins are installed at both ends of the horizontal pressure bar;

[0010] Lifting rings are used to connect the top transverse ribs of the side formwork of the box girder.

[0011] Turnbuckle, with the through pin and lifting ring connected at both ends, tightens the turnbuckle to make the transverse pressure bar act on the inner mold of the box girder through the support rod; the inner mold of the box girder is the box girder to be prepared, and the side mold of the box girder is the mold of the box girder to be prepared.

[0012] Optionally, the turnbuckle is a connecting member with adjustable length at both ends. One end of the turnbuckle is rotatably connected to the protruding end of the through pin, and the other end of the turnbuckle is rotatably connected to the lifting ring. By adjusting the length of the turnbuckle, the transverse pressure bar applies pressure away from and perpendicular to the transverse pressure bar to the inner formwork of the box girder through the support rod.

[0013] Optionally, at least two support rods are provided on each side of the bottom of the transverse pressure bar, and the support rods on the same side are provided at equal intervals along the length of the transverse pressure bar.

[0014] Optionally, the angle between the support rod and the transverse pressure bar is 90°±5°, and the bottom end of the support rod is provided with a flat plate structure extending to both sides.

[0015] Optionally, the vertical distance from the connection point between the lifting ring and the side formwork of the box girder to the top of the inner formwork of the box girder is equal to the vertical distance from the axis of the through pin to the bottom of the support rod.

[0016] Optionally, a hook is provided at one end of the turnbuckle near the lifting ring, and the turnbuckle is connected to the lifting ring via the hook.

[0017] Optionally, the support rod includes a fixed section and a telescopic section. The fixed section is fixedly connected to the transverse pressure bar, and the telescopic section is sleeved inside the fixed section and positioned by locking bolts.

[0018] Optionally, the two ends of the pin are provided with radially penetrating through holes, and anti-detachment pins are inserted in the through holes. The length of the anti-detachment pins is greater than the diameter of the pin.

[0019] Optionally, the transverse pressure bar is provided with downwardly recessed reinforcing grooves at intervals along its length, and the extension direction of the reinforcing grooves is perpendicular to the length direction of the transverse pressure bar.

[0020] Optionally, the transverse brace is an integral crossbeam formed by splicing at least two long strip-shaped members along the length direction. The splicing of the transverse brace forms a continuous load-bearing structure through fixed connection, and the length of the transverse brace is adapted to the width of the box girder top plate.

[0021] As can be seen from the above technical solution, this application provides an anti-buoyancy device for the inner formwork of a precast box girder, including: a transverse pressure bar, a support rod, a through pin, a lifting ring, and a turnbuckle; the support rod is connected to both sides of the transverse pressure bar, and the bottom of the support rod extends out of the bottom of the transverse pressure bar; the through pin is set at both ends of the transverse pressure bar; the lifting ring is connected to the top transverse rib of the box girder side formwork; the two ends of the turnbuckle are respectively connected to the through pin and the lifting ring, and by tightening the turnbuckle, the transverse pressure bar acts on the inner formwork of the box girder through the support rod. Through the main body of the transverse pressure bar, the turnbuckle is connected to the side formwork of the box girder, and tightening the turnbuckle secures the transverse pressure bar, which is supported on the inner formwork of the box girder by the support rod, so as to solve the problem of the inner formwork floating during the concrete pouring of the precast box girder. Attached Figure Description

[0022] To more clearly illustrate the technical solution of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 A structural diagram of the anti-buoyancy device for the inner formwork of the precast box girder provided in the embodiments of this application;

[0024] Figure 2 A side view of the anti-buoyancy device for the inner formwork of a precast box girder provided in an embodiment of this application;

[0025] Figure 3 This is a schematic diagram of the transverse pressure bar structure provided in an embodiment of this application.

[0026] Figure label:

[0027] Among them, 1-lateral pressure bar; 2-support rod; 3-through pin; 4-lifting ring; 5-turn bolt; 6-hook; 7-anti-detachment pin; 8-reinforcing groove; 100-box girder side formwork; 200-box girder inner formwork. Detailed Implementation

[0028] The embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described below do not represent all embodiments consistent with this application. They are merely examples of systems and methods consistent with some aspects of this application as detailed in the claims.

[0029] In bridge construction, the quality of precast box girders plays a crucial role in the stability and durability of the entire bridge structure. Concrete pouring is a critical step in the precast box girder production process. The inner formwork, made of integral steel, is prone to floating during the pouring of the bottom slab due to the impact of the concrete and the significant buoyancy of the inner formwork. This can easily lead to dimensional deviations in the bottom slab and web, affecting the internal structure and strength of the box girder, and consequently causing problems such as large deviations in the thickness of the concrete cover for the top slab and web reinforcement, concrete misalignment, and defects in the appearance of the precast beam.

[0030] To address the issues of delayed response, insufficient braking effectiveness, and reliance on passive protection that lead to malfunctions in mine car blocking measures during inclined shaft winch traction in coal mines, see [reference needed]. Figure 1 and Figure 2 , Figure 1 This is a schematic diagram of the anti-buoyancy device structure for the inner mold of the precast box girder provided in the embodiments of this application. Figure 2 This is a side view of the structure of the anti-buoyancy device for the inner mold of the precast box girder provided in the embodiment of this application.

[0031] The anti-buoyancy device for the inner formwork of the precast box girder includes:

[0032] A transverse pressure bar 1; a support rod 2, the support rod 2 being connected to both sides of the transverse pressure bar 1, with the bottom of the support rod 2 extending beyond the bottom of the transverse pressure bar 1; a through pin 3, the through pin 3 being located at both ends of the transverse pressure bar 1; a lifting ring 4, the lifting ring 4 being connected to the top transverse rib of the box girder side mold 100; and a turnbuckle 5, the two ends of the turnbuckle 5 being connected to the through pin 3 and the lifting ring 4 respectively. By tightening the turnbuckle 5, the transverse pressure bar 1 acts on the box girder inner mold 200 through the support rod 2. The box girder inner mold 200 is the box girder to be prepared, and the box girder side mold 100 is the mold for preparing the box girder.

[0033] The transverse pressure bar 1 is an anti-buoyancy component that can stably apply downward pressure during concrete pouring, effectively preventing the inner formwork 200 of the box girder from floating. Both ends of the transverse pressure bar 1 are equipped with through pins 3 for easy connection to turnbuckles 5.

[0034] Support rod 2 connects to both sides of the transverse pressure bar 1, with its bottom extending beyond the bottom of the transverse pressure bar 1, directly acting on the inner mold 200 of the box girder. The design of support rod 2 ensures that the pressure of the transverse pressure bar 1 is evenly transmitted to the inner mold 200 of the box girder, avoiding damage to the internal structure of the box girder caused by excessive local pressure. At the same time, the extended part of support rod 2 increases its contact area with the inner mold 200 of the box girder, further improving the anti-buoyancy effect.

[0035] The through pin 3 is located at both ends of the transverse pressure bar 1, serving as the connection point between the turnbuckle 5 and the transverse pressure bar 1. The design of the through pin 3 ensures both the stability of the connection and facilitates disassembly and replacement.

[0036] The lifting ring 4 is connected to the top transverse rib of the side formwork 100 of the box girder, serving as the other end connection point of the turnbuckle 5. The connection between the lifting ring 4 and the turnbuckle 5 enables the tension to be applied evenly during the tightening process, avoiding damage to the device or deformation of the internal structure of the box girder caused by uneven tension.

[0037] The turnbuckle 5 is connected to the mandrel 3 and the lifting ring 4 at both ends. By tightening the turnbuckle 5, the transverse pressure bar 1 can act on the inner formwork 200 of the box girder through the support rod 2, thus achieving an anti-buoyancy effect. The tightening process of the turnbuckle 5 is simple and convenient, and the tightness can be adjusted according to actual needs to meet the anti-buoyancy requirements under different working conditions.

[0038] The anti-buoyancy device for the inner formwork of precast box girders is applied during the concrete pouring process of precast box girders, effectively preventing the inner formwork 200 of the box girder from floating during the concrete pouring process.

[0039] In some embodiments, the turnbuckle 5 is a connecting member with adjustable length at both ends. One end of the turnbuckle 5 is rotatably connected to the protruding end of the through pin 3, and the other end of the turnbuckle 5 is rotatably connected to the lifting ring 4. By adjusting the length of the turnbuckle 5, the transverse pressure bar 1 applies pressure to the inner mold 200 of the box girder away from and perpendicular to the transverse pressure bar 1 through the support rod 2.

[0040] The turnbuckle 5 is an adjustable-length connecting component, allowing the anti-buoyancy device for the precast box girder inner formwork to adapt to precast box girders of different sizes. Simultaneously, the rotatable connection between the turnbuckle 5, the through pin 3, and the lifting ring 4 ensures greater stability of the entire device under stress, reducing safety hazards caused by loosening or deformation of connecting components. By precisely adjusting the length of the turnbuckle 5, construction personnel can ensure that the transverse pressure bar 1 applies sufficient downward pressure to the box girder inner formwork 200 through the support rod 2, effectively preventing the inner formwork 200 from floating during concrete pouring, thereby guaranteeing the quality and safety of the precast box girder.

[0041] In some embodiments, at least two support rods 2 are provided on each side of the bottom of the transverse pressure bar 1, and the support rods 2 on the same side are equally spaced along the length of the transverse pressure bar 1. The equally spaced support rods 2 effectively distribute pressure, reducing the risk of damage to the box girder inner formwork 200 due to excessive local pressure. Furthermore, by providing at least two support rods 2, even if individual support rods 2 fail or are damaged, the other support rods 2 can continue to function, ensuring the continuous and effective operation of the entire precast box girder inner formwork anti-buoyancy device.

[0042] In some embodiments, the angle between the support rod 2 and the transverse pressure bar 1 is 90°±5°, and the bottom end of the support rod 2 is provided with a flat plate structure extending to both sides.

[0043] By incorporating a flat plate structure, the contact area between the support rod 2 and the ground or supporting surface is increased, reducing the risk of damage to the inner formwork 200 of the box girder due to excessive local pressure. Simultaneously, setting the angle between the support rod 2 and the transverse pressure bar to 90°±5° ensures that the support rod 2 can apply force perpendicularly or approximately perpendicularly to the transverse pressure bar 1, resulting in more direct and uniform pressure transmission and further enhancing the anti-buoyancy effect.

[0044] In some embodiments, the vertical distance from the connection point of the lifting ring 4 to the side formwork 100 of the box girder to the top of the inner formwork 200 of the box girder is equal to the vertical distance from the axis of the through pin 3 to the bottom of the support rod 2.

[0045] The vertical distance from the connection point of the lifting ring 4 and the side formwork 100 of the box girder to the top of the inner formwork 200 of the box girder is equal to the vertical distance from the axis of the through pin 3 to the bottom of the support rod 2. This is mainly used to ensure that the tension of the turnbuckle 5 can be efficiently and stably converted into downward pressure on the inner formwork 200 of the box girder, avoiding interference from additional forces and improving the accuracy and reliability of the anti-buoyancy effect.

[0046] Specifically, when the two vertical distances are equal, the axis of the turnbuckle 5 is at the same height as the force-bearing plane of the transverse pressure bar 1 in the vertical direction, and the tensile force of the turnbuckle 5 is nearly vertical. If the distances are unequal, the turnbuckle 5 will tilt at an angle, and its tensile force will be decomposed into horizontal and vertical components. If the height of the connection point of the lifting ring 4 is higher than the corresponding height of the axis of the through pin 3, the vertical component of the tensile force will be upward, which will offset part of the weight of the transverse pressure bar 1, weaken the downward pressure on the support rod 2, and reduce the anti-buoyancy effect.

[0047] If the height of the connection point of the lifting ring 4 is lower than the corresponding height of the axis of the through pin 3, the vertical component of the tension will be downward, which will cause excessive pressure on the support rod 2 by the transverse pressure bar 1, potentially causing excessive downward pressure on the inner mold or deformation of the support rod 2. Equal distances can eliminate the interference of the vertical component, allowing all the tension to be converted into downward pressure on the support rod 2 through the transverse pressure bar 1, ensuring that the anti-buoyancy force is controllable.

[0048] The transverse pressure bar 1 acts on the inner mold through the support rod 2, and its two ends are constrained by the tension of the turnbuckle 5. When the two vertical distances are equal, the torque formed by the tension of the turnbuckle 5 at both ends on the transverse pressure bar 1 is equal in magnitude and opposite in direction, which can balance each other and prevent the transverse pressure bar 1 from tilting or twisting.

[0049] If the distances are not equal, the torque at both ends will be unbalanced, and the transverse pressure bar 1 will deflect to one side, resulting in uneven contact between the support rod 2 and the inner mold. This will not only reduce the anti-buoyancy effect, but may also cause local deformation of the inner mold.

[0050] When the distance is equal, the adjustment process of turnbuckle 5 is more intuitive. Simply rotate turnbuckle 5 to tighten the tension, and the downward pressure can be directly transmitted through the transverse pressure bar 1. There is no need for additional calculation or angle adjustment compensation, which reduces the impact of manual operation error on the force effect and ensures that the force state of the anti-buoyancy device is consistent when different construction personnel install it, thus improving the versatility and stability of the device.

[0051] In some embodiments, a hook 6 is provided at one end of the turnbuckle 5 near the lifting eye 4, and the turnbuckle 5 is connected to the lifting eye 4 via the hook 6. This connection via the hook 6 facilitates quick and accurate connection or disconnection of the turnbuckle 5 and the lifting eye 4 by construction workers during installation and disassembly, improving construction efficiency. Furthermore, the hook 6 is made of high-strength alloy steel and other wear-resistant and corrosion-resistant materials to ensure the durability and reliability of the connection.

[0052] In some embodiments, the support rod 2 includes a fixed section and a telescopic section. The fixed section is fixedly connected to the transverse pressure bar 1, and the telescopic section is fitted inside the fixed section and positioned by locking bolts. The design of the telescopic section allows construction personnel to adjust the length of the support rod 2 according to actual needs, adapting to different sizes of box girder inner formwork 200. Positioning by locking bolts ensures the stability of the telescopic section after adjustment, preventing slippage or loosening during stress, thus guaranteeing the stability and reliability of the anti-buoyancy device. Furthermore, the fixed connection between the fixed section and the transverse pressure bar 1 makes the entire support rod 2 structure more robust, capable of withstanding greater downward pressure, further enhancing the anti-buoyancy effect.

[0053] In some embodiments, the two ends of the through pin 3 are provided with radially penetrating through holes, and anti-detachment pins 7 are inserted into the through holes. The length of the anti-detachment pins 7 is greater than the diameter of the through pin 3. The anti-detachment pins 7 ensure that the through pin 3 is firmly fixed in the predetermined position after installation, effectively preventing it from falling off during construction due to excessive force or vibration. The anti-detachment pins 7 are also made of high-strength alloy steel and other wear-resistant and corrosion-resistant materials to ensure their long-term stability and reliability. Furthermore, the anti-detachment pins 7 facilitate the installation and removal of the through pin 3 by construction personnel, improving construction efficiency. The cooperation between the through pin 3 and the anti-detachment pins 7 further enhances the overall stability and safety of the anti-buoyancy device for the precast box girder inner formwork.

[0054] In some embodiments, such as Figure 3 As shown, the transverse pressure bar 1 has downwardly recessed reinforcing grooves 8 spaced along its length, with the extension direction of the reinforcing grooves 8 perpendicular to the length direction of the transverse pressure bar 1. The reinforcing grooves 8 not only reduce the weight of the transverse pressure bar 1 but also increase its structural strength, making it more resistant to external forces and less prone to deformation. The reinforcing grooves 8 optimize material distribution, allowing stress to be distributed more evenly across the transverse pressure bar 1, thereby improving the overall load-bearing capacity and stability. Furthermore, the vertical extension direction of the reinforcing grooves 8 helps resist forces from different directions, enhancing the adaptability and durability of the anti-buoyancy device.

[0055] In some embodiments, the transverse brace 1 is an integral crossbeam formed by splicing at least two long strip-shaped members along its length. The splice joints of the transverse brace 1 are fixedly connected to form a continuous load-bearing structure, and the length of the transverse brace 1 is adapted to the width of the box girder top plate. The integral crossbeam formed by splicing at least two long strip-shaped members along its length not only enhances the overall strength of the transverse brace 1 but also allows it to adapt to box girder top plates of different widths, improving the versatility and practicality of the anti-buoyancy device for the precast box girder inner formwork. Furthermore, the splice joints of the transverse brace 1 are fixedly connected, such as by welding or bolting, ensuring the stability of the splice joints and avoiding safety hazards caused by weak connections. The integral crossbeam design allows the transverse brace 1 to distribute stress evenly, improving the anti-buoyancy effect.

[0056] This application provides an anti-buoyancy device for the inner formwork of a precast box girder, comprising: a transverse pressure bar 1, a support rod 2, a through pin 3, a lifting ring 4, and a turnbuckle 5; the support rod 2 is connected to both sides of the transverse pressure bar 1, and the bottom of the support rod 2 extends out of the bottom of the transverse pressure bar 1; the through pin 3 is set at both ends of the transverse pressure bar 1; the lifting ring 4 is connected to the top transverse rib of the box girder side formwork 100; the two ends of the turnbuckle 5 are respectively connected to the through pin 3 and the lifting ring 4, and by tightening the turnbuckle 5, the transverse pressure bar 1 acts on the inner formwork 200 of the box girder through the support rod 2. Through the main body of the transverse pressure bar 1, the turnbuckle 5 is connected to the side formwork 100 of the box girder, and tightening the turnbuckle 5 secures the transverse pressure bar 1, which is supported on the inner formwork 200 of the box girder by the support rod 2, so as to solve the problem of the inner formwork floating during the concrete pouring of the precast box girder.

[0057] Similar parts between the embodiments provided in this application can be referred to mutually. The specific implementation methods provided above are only a few examples under the overall concept of this application and do not constitute a limitation on the scope of protection of this application. For those skilled in the art, any other implementation methods extended from the solution of this application without creative effort shall fall within the scope of protection of this application.

Claims

1. A precast box girder inner mold anti-buoyancy device, characterized in that, include: Horizontal pressure bar (1); Support rod (2), the support rod (2) is connected to both sides of the transverse pressure bar (1), and the bottom of the support rod (2) extends out of the bottom of the transverse pressure bar (1); Through pin (3), the through pin (3) is provided at both ends of the transverse pressure bar (1); Lifting ring (4), the lifting ring (4) is connected to the top transverse rib of the side formwork (100) of the box girder; Turnbuckle (5), the two ends of the turnbuckle (5) are respectively connected to the through pin (3) and the lifting ring (4). By tightening the turnbuckle (5), the transverse pressure bar (1) acts on the inner formwork (200) of the box girder through the support rod (2); The inner mold (200) of the box girder is the box girder to be prepared, and the side mold (100) of the box girder is the mold for preparing the box girder.

2. The anti-buoyancy device for the inner mold of the precast box girder according to claim 1, characterized in that, The turnbuckle (5) is a connecting member with adjustable length at both ends. One end of the turnbuckle (5) is rotatably connected to the protruding end of the through pin (3), and the other end of the turnbuckle (5) is rotatably connected to the lifting ring (4). By adjusting the length of the turnbuckle (5), the transverse pressure bar (1) applies pressure away from and perpendicular to the transverse pressure bar (1) to the inner mold of the box girder (200) through the support rod (2).

3. The anti-buoyancy device for the inner mold of the precast box girder according to claim 1, characterized in that, At least two support rods (2) are provided on each side of the bottom of the transverse pressure bar (1), and the support rods (2) on the same side are equally spaced along the length direction of the transverse pressure bar (1).

4. The anti-buoyancy device for the inner mold of the precast box girder according to claim 1, characterized in that, The angle between the support rod (2) and the transverse pressure bar (1) is 90°±5°, and the bottom end of the support rod (2) is provided with a flat plate structure extending to both sides.

5. The anti-buoyancy device for the inner mold of the precast box girder according to claim 1, characterized in that, The vertical distance from the connection point of the lifting ring (4) to the side formwork (100) of the box girder to the top of the inner formwork (200) of the box girder is equal to the vertical distance from the axis of the through pin (3) to the bottom of the support rod (2).

6. The anti-buoyancy device for the inner mold of the precast box girder according to claim 1, characterized in that, The turnbuckle (5) is provided with a hook (6) at one end near the lifting ring (4), and the turnbuckle (5) is connected to the lifting ring (4) through the hook (6).

7. The anti-buoyancy device for the inner formwork of a precast box girder according to claim 1, characterized in that, The support rod (2) includes a fixed section and a telescopic section. The fixed section is fixedly connected to the transverse pressure bar (1), and the telescopic section is sleeved inside the fixed section and positioned by locking bolts.

8. The anti-buoyancy device for the inner mold of the precast box girder according to claim 1, characterized in that, The two ends of the through pin (3) are provided with radial through holes, and anti-detachment pins (7) are inserted in the through holes. The length of the anti-detachment pins (7) is greater than the diameter of the through pin (3).

9. The anti-buoyancy device for the inner mold of the precast box girder according to claim 1, characterized in that, The transverse pressure bar (1) is provided with downwardly recessed reinforcing grooves (8) at intervals along its length, and the extension direction of the reinforcing grooves (8) is perpendicular to the length direction of the transverse pressure bar (1).

10. The anti-buoyancy device for the inner mold of the precast box girder according to claim 1, characterized in that, The transverse pressure bar (1) is an integral crossbeam formed by splicing at least two long strip-shaped members along the length direction. The splicing joint of the transverse pressure bar (1) forms a continuous force-bearing structure through a fixed connection, and the length of the transverse pressure bar (1) is adapted to the width of the top plate of the box girder.

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