A precast box girder internal formwork device

Abstract

This utility model discloses an internal formwork device for precast box girders, including a box girder body with an internal cavity. Rigid and flexible formwork are arranged within the cavity, with adjacent rigid formworks connected by flexible formworks. Each rigid formwork has a support plate, and each support plate has a support rod. An adjustment component is located in the center of the cavity, and four support rods are connected to the adjustment component to adapt to different types of precast box girders. This utility model, through the synergy of the adjustment component, support rods, rigid formworks, and flexible formworks, can flexibly adjust the formwork component shape to adapt to precast box girders with different internal cavity sizes. One formwork device can cover the precasting of multiple box girder models, reducing the types and quantities of formwork required, simplifying the formwork replacement and debugging process during construction, and reducing the overall cost of precast construction in terms of material reserves and labor input, thereby improving the economy and operability of bridge precast engineering.

Description

Technical Field

[0001] This utility model relates to the field of building formwork technology, and in particular to an internal formwork device for precast box girders. Background Technology

[0002] In the field of bridge construction, precast box girders have become one of the core components of the superstructure of long-span bridges due to their significant advantages such as short construction period, strong structural stability and easy quality control. Their production mode is usually to complete the casting and molding in advance in an independent precasting site, and then quickly install them through hoisting operations after the substructure of the bridge is completed, which greatly shortens the time cost of on-site construction.

[0003] However, the inner formwork of precast box girders is a key tooling for ensuring the dimensional accuracy and forming quality of the internal structure of the box girder. Its design rationality directly affects the prefabrication efficiency and production cost. At present, the inner formwork of precast box girders widely used in the industry is mostly a fixed structure. Its dimensional parameters are completely matched with the internal cavity of a specific model of box girder, which can only meet the prefabrication requirements of a single specification of box girder.

[0004] In actual engineering projects, different bridge projects have significantly different requirements for the span, cross-sectional dimensions, and load-bearing capacity of box girders. This necessitates the prefabrication of various types of box girders to adapt to diverse construction scenarios. When it is necessary to change the type of box girder, the existing fixed inner formwork cannot be adjusted in size and must be scrapped entirely, requiring the redesign and fabrication of new inner formwork. This approach not only results in a large waste of old formwork materials and increases equipment investment costs, but also delays the prefabrication schedule due to the long formwork production cycle, severely restricting the flexibility and economy of prefabricated box girder production.

[0005] To address this issue, a precast box girder internal formwork device is proposed to solve the problems existing in the current technology. Utility Model Content

[0006] The purpose of this utility model is to address the aforementioned problems by providing an internal formwork device for precast box girders. This utility model, through the coordinated operation of adjustable components, support rods, rigid formwork, and flexible formwork, can flexibly adjust the formwork component shape to adapt to precast box girders with different internal cavity sizes. It eliminates the need for repeated formwork fabrication, saving costs and improving precasting efficiency. One formwork device can cover the precasting of multiple box girder models, reducing the types and quantities of formwork required, simplifying formwork replacement and debugging processes during construction, and reducing the overall cost of precast construction in terms of material reserves and labor input. This enhances the economy and operability of bridge precast engineering. To achieve the above-mentioned utility model objectives, the technical solution adopted is as follows:

[0007] According to one aspect of the present invention, a precast box girder internal formwork device is provided, comprising a box girder body, wherein a cavity is provided inside the box girder body, and a formwork assembly is provided inside the cavity. The formwork assembly includes a rigid formwork and a flexible formwork, and the flexible formwork has multiple flexible grooves. Four rigid formworks fit around the cavity, and adjacent rigid formworks are connected by flexible formworks. Each rigid formwork is provided with a support plate, and each support plate is provided with a support rod. An adjustment component is provided in the middle of the cavity, and the four support rods are all connected to the adjustment component for adapting to different types of precast box girders.

[0008] Preferably, the adjustment assembly includes an adjustment disc disposed in the middle of the cavity. The adjustment disc has four arc-shaped through slots, which are evenly distributed around its circumference. The four support rods are symmetrically arranged in pairs. Each support rod has a buckle, and each buckle has a sliding rod. Each sliding rod is disposed in a corresponding arc-shaped through slot. Each support rod has a limiting sleeve, and a connecting rod is provided between two opposite limiting sleeves. One of the connecting rods has a drive motor, and the output end of the drive motor is connected to the adjustment disc.

[0009] Preferably, each of the rigid templates and flexible templates has a groove at both ends, a connecting plate is provided between the rigid templates and flexible templates, and each connecting plate has a protrusion at both ends that cooperates with the groove.

[0010] Preferably, each of the arc-shaped through slots has a limiting slot on both the upper and lower sides, and each limiting slot has multiple limiting blocks installed by hinges. Each limiting block and the limiting slot is provided with a limiting spring, and each limiting block is tilted in the same direction.

[0011] Preferably, each of the support rods is a telescopic rod, and each support rod is provided with a limiting spring.

[0012] In summary, due to the adoption of the above technical solution, the beneficial effects of this utility model are:

[0013] The precast box girder internal formwork device described in this utility model can flexibly adjust the formwork component shape by coordinating the adjustment components with the support rods, rigid formwork, and flexible formwork to adapt to precast box girders with different internal cavity sizes. It eliminates the need for repeated formwork production, saving costs and improving precasting efficiency. One formwork device can cover the precasting of multiple box girder models, reducing the types and quantities of formwork reserves, simplifying the formwork replacement and debugging process during construction, reducing the overall cost of precast construction in terms of material reserves and labor input, and improving the economy and operability of bridge precast engineering. Attached Figure Description

[0014] Figure 1 This is a perspective view of the present invention;

[0015] Figure 2 This is a utility model Figure 1 Rear view;

[0016] Figure 3 This is a utility model Figure 1 The front view;

[0017] Figure 4 This is a utility model Figure 3 A magnified cross-sectional view of point A;

[0018] Figure 5 This is a utility model Figure 3 Enlarged view of point B;

[0019] In the attached diagram: 1. Box girder body; 2. Cavity; 3. Rigid template; 4. Flexible template; 5. Flexible groove; 6. Support plate; 7. Support rod; 8. Adjusting disc; 9. Arc-shaped through groove; 10. Buckle; 11. Slide rod; 12. Limiting sleeve; 13. Connecting rod; 14. Drive motor; 15. Groove; 16. Connecting plate; 17. Protrusion; 18. Limiting groove; 19. Limiting block; 20. Limiting spring. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this utility model clearer, the following detailed description is provided with reference to the accompanying drawings and preferred embodiments. However, it should be noted that many details listed in the specification are merely to provide the reader with a thorough understanding of one or more aspects of the utility model, and these aspects can be achieved even without these specific details.

[0021] Please see Figures 1 to 5 This utility model provides an internal formwork device for precast box girders, the technical solution of which is as follows:

[0022] The system includes a box girder body 1, which has a cavity 2 inside. A template assembly is provided inside the cavity 2. The template assembly includes a rigid template 3 and a flexible template 4. The flexible template 4 has multiple flexible grooves 5. The four rigid templates 3 fit around the cavity 2, and adjacent rigid templates 3 are connected by the flexible templates 4. Each rigid template 3 is provided with a support plate 6, and each support plate 6 is provided with a support rod 7. An adjustment assembly is provided in the middle of the cavity 2, and the four support rods 7 are all connected to the adjustment assembly to adapt to different models of precast box girders.

[0023] The required size of the precast box girder is measured according to the requirements. Then, by adjusting the components and using multiple support rods 7, four rigid templates 3 and flexible templates 4 are spliced ​​together. The initial shape is then achieved with the help of an external forming mold, followed by pouring. During the process, the adjusting components continuously provide support force to the rigid templates 3 to facilitate the final box girder forming. The rigid templates 3 ensure the structural strength and dimensional accuracy of the basic structure, while the flexible templates 4 and flexible grooves 5 give the template components the ability to deform, adapting to the shape adjustment when the box girder size changes. At the same time, it alleviates the stress concentration caused by the forced deformation of the templates and extends the service life of the templates.

[0024] By adjusting the coordination of the components with the support rod 7, rigid template 3, and flexible template 4, the formwork component shape can be flexibly adjusted to adapt to precast box girders with different internal cavity sizes. There is no need to repeatedly make templates, saving costs and improving precasting efficiency. One set of template device can cover the precasting of multiple types of box girders, reducing the types and quantities of templates to be stored, simplifying the template replacement and debugging process during construction, reducing the overall cost of precast construction in terms of material reserves and labor input, and improving the economy and operability of bridge precasting projects.

[0025] The adjustment assembly includes an adjustment disc 8 disposed in the middle of the cavity 2. The adjustment disc 8 has four arc-shaped through slots 9, which are evenly distributed around its circumference. The four support rods 7 are symmetrically arranged in pairs. Each support rod 7 is a telescopic rod and has a limiting spring inside. Each support rod 7 has a buckle 10 and a sliding rod 11. Each sliding rod 11 is disposed in a corresponding arc-shaped through slot 9. Each support rod 7 has a limiting sleeve 12, and a connecting rod 13 is provided between two opposite limiting sleeves 12. One of the connecting rods 13 has a drive motor 14, and the output end of the drive motor 14 is connected to the adjustment disc 8.

[0026] The drive motor 14 drives the adjusting disc 8 to rotate. Under the action of the arc-shaped through groove 9 and the sliding rod 11, and under the restriction of the limiting sleeve 12, each support rod 7 moves along the direction limited by the limiting sleeve 12 for adjustment until it abuts against the corresponding rigid template 3. Then, the staff connects the support rod 7 to the corresponding rigid template 3 through the support plate 6. The arc-shaped through groove 9 cooperates with the sliding rod 11 and the buckle 10, combined with the telescopic rod and the limiting spring, so that the support rod 7 can flexibly adjust its position and length along the arc trajectory, accurately adapt to different box girder cavity sizes, realize the adaptation of the template component to multiple models of precast box girders, and improve the versatility of the device.

[0027] The limiting sleeve 12 and connecting rod 13 form a stable support frame. The drive motor 14 drives the adjusting disc 8 to make the adjustment process synchronous and controllable, ensuring the structural stability of the template assembly during adjustment, avoiding template deformation due to uneven force, and ensuring the dimensional accuracy of the precast box girder.

[0028] Each of the rigid template 3 and flexible template 4 has a groove 15 at both ends. A connecting plate 16 is provided between the rigid template 3 and the flexible template 4, and each connecting plate 16 has a protrusion 17 at both the left and right ends that cooperates with the groove 15.

[0029] Enhanced adaptability enables multiple rigid templates 3 and flexible templates 4 to adapt to precast box girders of different sizes; the connecting plate 16 serves as an intermediate transition component, ensuring connection rigidity through the protrusion 17 and groove 15, and also providing buffer space for relative displacement and angle adjustment of rigid template 3 and flexible template 4 when the template assembly deforms with the adjustment assembly due to its own structure, adapting to the flexible adjustment of the template assembly without hindering the overall deformation to adapt to different box girder sizes;

[0030] The interlocking structure of the groove 15 and the convex strip 17 allows the rigid template 3 and the flexible template 4 to form a mechanical interlock, which greatly improves the connection strength and avoids deformation and cracking of the template splice joint due to concrete lateral pressure and vibration during the prefabrication process. This ensures the overall stability of the template assembly and guarantees the forming quality of the inner wall of the box girder.

[0031] Each of the arc-shaped through slots 9 has a limiting slot 18 on both the upper and lower sides, and each limiting slot 18 has multiple limiting blocks 19 installed in it by hinge. Each limiting block 19 and the limiting slot 18 is provided with a limiting spring 20, and each limiting block 19 is inclined in the same direction.

[0032] The limiting block 19, together with the limiting groove 18 and the limiting spring 20, forms a "one-way guiding + elastic limiting" function for the sliding rod 11. When the sliding rod 11 is adjusted along the arc-shaped through groove 9, the limiting block 19 can be squeezed and contracted in the forward direction without hindering the adjustment; in the reverse direction, due to the tilt and spring support, the sliding rod 11 is locked, which prevents the template assembly from shifting due to the pressure of box girder pouring and vibration after adjustment, ensuring the stability of the template shape and improving the accuracy of prefabricated dimensions.

[0033] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A precast box girder inner formwork apparatus, characterized by, include: The box girder body (1) has a cavity (2) inside. The cavity (2) has a template assembly. The template assembly includes a rigid template (3) and a flexible template (4). The flexible template (4) has multiple flexible grooves (5). The four rigid templates (3) fit around the cavity (2). The two adjacent rigid templates (3) are connected by the flexible template (4). Each rigid template (3) has a support plate (6). Each support plate (6) has a support rod (7). The cavity (2) has an adjustment assembly in the middle. The four support rods (7) are connected to the adjustment assembly to adapt to different types of precast box girders.

2. The precast box girder internal formwork device according to claim 1, characterized in that: The adjustment assembly includes an adjustment disc (8) disposed in the middle of the cavity (2). The adjustment disc (8) has four arc-shaped through slots (9) and the four arc-shaped through slots (9) are evenly distributed around the adjustment disc (8). The four support rods (7) are symmetrically arranged in pairs. Each support rod (7) is provided with a buckle (10) and each buckle (10) is provided with a slide rod (11). Each slide rod (11) is disposed in the corresponding arc-shaped through slot (9). Each support rod (7) is provided with a limiting sleeve (12), and a connecting rod (13) is provided between two opposite limiting sleeves (12). One of the connecting rods (13) is provided with a drive motor (14), and the output end of the drive motor (14) is connected to the adjustment disc (8).

3. The precast box girder internal formwork device according to claim 1, characterized in that: Each of the rigid template (3) and the flexible template (4) has a groove (15) at both ends. A connecting plate (16) is provided between the rigid template (3) and the flexible template (4), and each connecting plate (16) has a protrusion (17) at both the left and right ends that cooperates with the groove (15).

4. The precast box girder internal formwork device according to claim 2, characterized in that: Each of the arc-shaped through grooves (9) has a limiting groove (18) on both the upper and lower sides, and each limiting groove (18) has multiple limiting blocks (19) installed in it by hinge. Each limiting block (19) and the limiting groove (18) are provided with a limiting spring (20), and each limiting block (19) is inclined in the same direction.

5. The precast box girder internal formwork device according to claim 1, characterized in that: Each of the support rods (7) is a telescopic rod, and each support rod (7) is provided with a limiting spring.

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