Reverse hanging formwork structure for cast-in-place bridge deck slab of steel-concrete composite beam

Abstract

The utility model relates to the technical field of steel-concrete composite beam bridge deck slab construction, in particular to a reverse hanging formwork structure for a steel-concrete composite beam cast-in-place bridge deck slab. The reverse hanging formwork structures are arranged on the flange portion of a steel-concrete composite beam cast-in-place bridge deck slab, the flange portion of a steel beam, the interior of a steel beam box body and the position between every two adjacent steel beam box bodies. The reverse hanging formwork structure is provided with a bamboo plywood bottom die; a plurality of longitudinal beam square pipes perpendicular to the bamboo plywood bottom die are arranged below the bamboo plywood bottom die; the longitudinal beam square tube is supported at the upper part of the lower cross beam; batten plates are fixed at at least one end of the lower cross beam; the batten plates are provided with opposite-pull screws used for connecting the batten plates and the bridge deck slab into a whole. A screw rod sleeve is sleeved on the opposite-pull screw rod; the screw rod sleeve is fixedly welded at the end part of the top plate of the steel beam; a positioning steel pipe used for being pressed and welded to the end face of the top plate of the steel beam is further welded to one side of the screw sleeve. The utility model has the characteristics of simple processing, convenient installation and disassembly, high stability, and adjustable thickness of concrete at the transition section of the flange part.

Description

Technical Field

[0001] This utility model relates to the field of steel-concrete composite beam bridge deck construction technology, specifically to an inverted formwork structure for cast-in-place steel-concrete composite beam bridge decks. Background Technology

[0002] With the development of urbanization and transportation networks, the number of newly built or reconstructed bridges crossing existing lines is increasing. These bridges not only need to meet the needs of daily highway traffic but also ensure the safe operation of the lines below, thus placing higher demands on bridge structures. Traditional bridge structural forms often have shortcomings when facing these special conditions. Steel-concrete composite beams, with their advantages of light weight, high strength, and convenient construction, have been widely used in modern bridge construction. However, when constructing cast-in-place bridge decks, traditional bridge deck formwork support methods often have many problems. For example, a large number of full-span scaffolds need to be built under the bridge, which not only consumes a lot of manpower, material resources, and time but also has high requirements for the traffic and site conditions under the bridge, making it difficult to implement in some complex terrains or areas with heavy traffic. In addition, the stability and safety of the full-span scaffolds also need to be strictly controlled, as the slightest carelessness may lead to safety accidents. Utility Model Content

[0003] To solve the above-mentioned technical problems, the purpose of this utility model is to propose an inverted formwork structure for cast-in-place bridge decks of steel-concrete composite beams.

[0004] To achieve the above objectives, this utility model adopts the following technical solution:

[0005] A reverse-hanging formwork structure for cast-in-place bridge deck of steel-concrete composite beam, wherein the reverse-hanging formwork structure is installed at the flange of the steel beam of the cast-in-place bridge deck of steel-concrete composite beam, inside the steel beam box, and between two adjacent steel beam boxes;

[0006] The anti-suspension formwork structure has a bamboo plywood bottom formwork for supporting the bridge deck; multiple longitudinal beams and square tubes perpendicular to the bamboo plywood bottom formwork are arranged below it; the longitudinal beams and square tubes are supported on the upper part of the lower crossbeam; at least one end of the lower crossbeam is fixed with a lacing plate; the lacing plate is provided with a tie rod for connecting the lacing plate and the bridge deck as a whole; a screw sleeve is fitted on the tie rod; the screw sleeve is welded and fixed to the end of the top plate of the steel beam; the tie rod drives the lacing plate and the lower crossbeam to pull upward and tighten, so that the bamboo plywood bottom formwork is close to the bridge deck; a positioning steel pipe for pressing and welding to the end face of the top plate of the steel beam is also welded to one side of the screw sleeve.

[0007] The inverted formwork structure installed at the flange of the cast-in-place bridge deck of the steel-concrete composite beam is a triangular structure, that is, a gusset plate is fixed at one end of the lower crossbeam; the inverted formwork structure is also provided with a threaded steel pipe for supporting the top plate of the steel beam; the threaded steel pipe is fixed at one end of the lower crossbeam and is set perpendicular to the lower crossbeam; the upper end of the threaded steel pipe is provided with an adjusting bolt for supporting the top plate of the steel beam and can be finely adjusted; an adjusting bolt is provided on one side of the threaded steel pipe.

[0008] The anti-hanging formwork structure, located inside the steel beam box and between two adjacent steel beam boxes, has two gusset plates at both ends of the lower crossbeam; both ends of the lower crossbeam are fixed with positioning steel pipes; a gap is formed between the positioning steel pipes fixed on the lower crossbeam and the positioning steel pipes fixed on the screw sleeve to clamp the top plate of the steel beam.

[0009] The present invention proposes an inverted formwork structure for cast-in-place bridge decks of steel-concrete composite beams, which features simple processing, convenient installation and disassembly, high stability, and adjustable concrete thickness in the transition section of the flange. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of a reverse-hanging formwork structure for the flange portion of a cast-in-place steel beam bridge deck according to this utility model;

[0011] Figure 2 This is a schematic diagram of the internal structure of the two box-shaped sections of a cast-in-place steel beam bridge deck and the reverse-hanging formwork structure of the adjacent area of ​​the two box-shaped sections according to the present invention;

[0012] Figure 3 This is a schematic diagram of the transverse bridge arrangement of a cast-in-place steel-concrete composite beam bridge deck inverted formwork structure according to the present invention;

[0013] Legend: 1. Tie rod; 2. Fastening nut; 3. Elevation adjusting tube; 4. Screw sleeve; 5. Positioning steel pipe; 6. Adjusting bolt; 7. Threaded steel pipe; 8. Pad; 9. Bracing plate; 10. Diagonal brace; 11. Lower crossbeam; 12. Adjusting plate; 13. Lower crossbeam; 14. Bamboo plywood bottom formwork; 15. Longitudinal beam square tube; 16. Steel beam top plate; 17. Steel beam box; 18. Bridge deck. Detailed Implementation

[0014] In order to clearly understand the above-mentioned objectives, features and advantages of this utility model, the present utility model will be described in detail below with reference to the accompanying drawings and embodiments.

[0015] Example 1: As Figure 1 As shown, and refer to Figure 3 A reverse-hanging formwork structure for cast-in-place bridge deck of steel-concrete composite beam, wherein the reverse-hanging formwork structure is installed at the flange of the steel beam, inside the steel beam box 17, and between two adjacent steel beam boxes 17.

[0016] In this embodiment, the inverted formwork structure is located at the flange of the steel beam and is a triangular structure. The inverted formwork structure has a bamboo plywood bottom formwork 14 for supporting the bridge deck 18. Multiple longitudinal beam square tubes 15 perpendicular to the bamboo plywood bottom formwork 14 are arranged below it. The longitudinal beam square tubes 15 are supported on the upper part of the lower crossbeam 11. A lacing plate 9 is fixed to one end of the lower crossbeam 11. A tie rod 1 for connecting the tie plate and the bridge deck is provided on the tie plate 9. A screw sleeve 4 is sleeved on the tie rod 1. The screw sleeve 4 is welded and fixed to the end of the top plate 16 of the steel beam. The tie rod 1 pulls the gusset plate 9 and the lower crossbeam 11 upwards, causing the bamboo plywood bottom mold 14 to be close to the bridge deck 18; a positioning steel pipe 5 for pressing and welding to the end face of the steel beam top plate is also welded to one side of the screw sleeve 4; the anti-hanging formwork structure is also provided with a threaded steel pipe 7 for supporting the steel beam top plate; the threaded steel pipe 7 is fixed to one end of the lower crossbeam 11 and is set perpendicular to the lower crossbeam 11; an adjusting bolt 6 for supporting the steel beam top plate and being finely adjustable is provided at the upper end of the threaded steel pipe 7; an adjusting bolt 6 is provided on one side of the threaded steel pipe.

[0017] To optimize the stress on the mold frame structure, fastening nuts 2 are set at both ends of the tie rod 1. A pad 8 is added above the fastening nut at the lower end. When installing the reverse-hanging mold frame structure, the lower part of the positioning steel pipe 5 is welded to the top plate of the steel beam, so that the screw sleeve 4 is in close contact with the end of the top plate of the steel beam and is spot-welded to fix it. This makes the reverse-hanging mold frame structure form a "pull-up and support-down" stress system. The position of the bamboo plywood bottom mold 14 can be adjusted by sliding the upper locking nut 2 and the two adjusting nuts 6.

[0018] Example 2: As Figure 2 As shown, a reverse-hanging formwork structure for cast-in-place steel-concrete composite beam bridge deck is described below. This type of reverse-hanging formwork structure is used inside the two box girders and in the adjacent areas of the two box girders.

[0019] A tie plate 9 is installed at both ends of the lower crossbeam 11. The tie plate 9 is divided into two parts, front and back, and fixed to both sides of the lower crossbeam 11, forming a hollow compartment in the middle. The bolt sleeve 4 passes through the hollow compartment and is welded to the tie plate 9 for fixation. When installing the inverted formwork structure, first fix the lower end fastening nut 2, the washer 8, and the tie rod. After welding the upper end positioning steel pipe 5 to the top plate of the steel beam, a "pull-up and support-down" force system is formed. The lower end positioning steel pipe 5 is used as a limiting device for the inverted formwork. The distance between the upper end positioning steel pipe 5 and the lower end positioning steel pipe 5 is the thickness of the top plate of the steel beam. The vertical position of the inverted formwork structure is adjusted by sliding the upper end fastening nut 2. After the inverted support is installed, install several longitudinal beam square tubes 15 and bamboo plywood bottom molds 14 to form a complete inverted formwork structure.

[0020] The screw sleeve, threaded steel pipe, positioning steel pipe, diagonal brace, and adjusting pipe are all hot-rolled seamless steel pipes. The gusset plate, adjusting plate, lower crossbeam, and pad are all steel plates. The lower crossbeam is an I-beam, and the longitudinal beam is a square tube. Except for bolted components, all other components are fixed by welding.

[0021] The formwork structure achieves fixation measures such as eliminating the need for through-hole punching on the top plate of the steel beam and adding connecting ear plates. The formwork structure is then welded to the top plate of the steel beam through positioning steel pipes, thus completing the connection between the formwork structure and the steel beam and simplifying the process.

[0022] This invention features an adjusting pipe above the screw sleeve that acts as a concrete pouring elevation band. It can be disassembled after construction, simplifying the construction process and prioritizing control of the concrete pouring height.

[0023] The triangular structure of the anti-hanging formwork is enhanced by diagonal bracing to increase its overall load-bearing capacity and stability.

[0024] The interior of the two boxes and the adjacent areas of the two boxes are equipped with a reverse-hanging formwork in the form of a beam structure. The number of components is small, the installation is simple, and the construction period is greatly shortened.

[0025] Specifically, the horizontal adjusting bolts on the threaded steel pipe can fine-tune the installation angle of the formwork structure, increasing the fault tolerance coefficient of the overall steel beam formwork structure installation, ensuring that the bottom formwork is flat and has good integrity after installation; the longitudinal adjusting bolts can be pressed against the bottom surface of the steel beam top plate, and the vertical position of the formwork structure can be adjusted freely according to the different thicknesses of the steel beam top plate, while increasing the stability of the formwork structure and improving the safety factor.

[0026] Specifically, fastening bolts are installed at both the upper and lower ends of the tie rod, and a washer is added to the lower fastening bolt to facilitate the installation and dismantling of the formwork system. At the same time, the stability of the formwork is improved by increasing the stress surface of the bottom bolt.

[0027] Specifically, in order to achieve an effective connection between the threaded steel pipe, the screw sleeve and the crossbeam, the gusset plate is welded and fixed to both sides of the crossbeam and extended to form a hollow compartment, which facilitates the insertion of the threaded steel pipe and the screw sleeve to achieve an effective connection. Diagonal bracing is also provided to strengthen the load-bearing capacity of the formwork.

[0028] The above description is merely a description of the basic principles, main features, and implementation methods of this utility model. Any person skilled in the art may make changes or improvements to the above technical solutions and apply them to other fields. However, any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this utility model, without departing from the technical solutions of this utility model, shall still fall within the protection scope of this utility model.

[0029] To apply this utility model, structural safety calculations must be performed based on the project engineering, and technical parameters suitable for the actual construction conditions of the project must be selected.

Claims

1. A reverse formwork structure for cast-in-situ bridge deck of steel-concrete composite beam, characterized in that: The aforementioned anti-suspension formwork structure is installed at the flange of the steel beam in the cast-in-place bridge deck of the steel-concrete composite beam, inside the steel beam box, and between two adjacent steel beam boxes; The anti-suspension formwork structure has a bamboo plywood bottom formwork for supporting the bridge deck; multiple longitudinal beams and square tubes perpendicular to the bamboo plywood bottom formwork are arranged below it; the longitudinal beams and square tubes are supported on the upper part of the lower crossbeam; at least one end of the lower crossbeam is fixed with a lacing plate; the lacing plate is provided with a tie rod for connecting the lacing plate and the bridge deck as a whole; a screw sleeve is fitted on the tie rod; the screw sleeve is welded and fixed to the end of the top plate of the steel beam; the tie rod drives the lacing plate and the lower crossbeam to pull upward and tighten, so that the bamboo plywood bottom formwork is close to the bridge deck; a positioning steel pipe for pressing and welding to the end face of the top plate of the steel beam is also welded to one side of the screw sleeve.

2. The reverse formwork structure for cast-in-situ composite beam and deck slab of a bridge according to claim 1, characterized in that: The inverted formwork structure installed at the flange of the cast-in-place bridge deck of the steel-concrete composite beam is a triangular structure, that is, a gusset plate is fixed at one end of the lower crossbeam; the inverted formwork structure is also provided with a threaded steel pipe for supporting the top plate of the steel beam; the threaded steel pipe is fixed at one end of the lower crossbeam and is set perpendicular to the lower crossbeam; the upper end of the threaded steel pipe is provided with an adjusting bolt for supporting the top plate of the steel beam and can be finely adjusted; an adjusting bolt is provided on one side of the threaded steel pipe.

3. The reverse formwork structure for cast-in-situ composite beam and deck slab of a bridge according to claim 1, characterized in that: The anti-hanging formwork structure, located inside the steel beam box and between two adjacent steel beam boxes, has two gusset plates at both ends of the lower crossbeam; both ends of the lower crossbeam are fixed with positioning steel pipes; a gap is formed between the positioning steel pipes fixed on the lower crossbeam and the positioning steel pipes fixed on the screw sleeve to clamp the top plate of the steel beam.

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