Semi-prefabricated and semi-cast-in-place concrete bridge structure and construction method

Abstract

The invention discloses a semi-prefabricated and semi-cast-in-place concrete bridge structure which comprises piers, a plurality of prefabricated beams are arranged on the piers and placed in parallel at intervals, a bridge deck is arranged at the tops of the prefabricated beams, construction joints are formed in the contact positions of the bottom face of the bridge deck and the tops of the prefabricated beams, and formwork support reserved holes are formed in the prefabricated beams. Opposite-penetrating steel pipes penetrate through preformed holes of the formwork supports, and a horizontal cross arm beam is formed by the multiple opposite-penetrating steel pipes. The structure that the multiple precast beams are overlapped with the cast-in-place bridge deck is adopted, the hoisting weight of a bridge is reduced, a large crane is not needed, hoisting of the precast beams can be completed through a common 25T truck crane, and the cast-in-place bridge deck part is formed by inserting opposite-penetrating steel pipes into preformed holes of a formwork support at the waist of the precast beams to serve as a bottom die of a horizontal cross arm beam supporting bridge deck. The problem that a supporting frame cannot be erected under a bridge is solved. The method is low in construction difficulty, low in construction cost, small in safety risk and suitable for large-scale application and popularization.

Description

Technical Field

[0001] This invention belongs to the field of highway bridge technology, and specifically relates to a semi-precast and semi-cast-in-place concrete bridge structure and its construction method. Background Technology

[0002] For the construction of small concrete bridges with a span of about 10m, precast bridges are often used. This usually requires the use of large truck cranes or special bridge erection equipment, which is costly. For small bridges with a small investment scale, it is often not feasible to invest in large hoisting equipment. If the method of using cast-in-place concrete is adopted, it is impossible to erect scaffolding for support because the bridge is located in a riverbed with flowing water, making it impossible to carry out bridge concrete construction. Summary of the Invention

[0003] The main objective of this invention is to provide a semi-precast and semi-cast-in-place concrete bridge structure and construction method, which solves the problem that in existing bridge construction using cast-in-place construction, scaffolding cannot be erected for support because the lower part of the bridge is in a riverbed flow state.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a semi-precast and semi-cast-in-place concrete bridge structure, including a pier, a plurality of precast beams are provided on the pier, the plurality of precast beams are placed in parallel and spaced apart, a bridge deck is provided on the top of the precast beams, a construction joint is provided at the contact position between the bottom surface of the bridge deck and the top of the precast beams, a pre-reserved hole for a template support is provided on the precast beams, through which a through steel pipe is passed, and the plurality of through steel pipes form a horizontal crossbeam.

[0005] Furthermore, the precast beams are equipped with stirrups, with the top portion of the stirrups extending into the bridge deck.

[0006] Furthermore, the precast beams are also equipped with longitudinal reinforcement bars in the waist and bottom, and the bridge deck is equipped with longitudinal reinforcement bars, distribution bars, and stirrups.

[0007] Furthermore, the pre-drilled holes for the formwork supports are located at the waist of the precast beam, and multiple pre-drilled holes for the formwork supports are located at the same elevation.

[0008] Furthermore, square timber and plywood are provided at the bottom and sides of the bridge deck, and adjusting pads are provided at the bottom of the square timbers. The adjusting pads are placed on the horizontal crossbeams formed by the through steel pipes.

[0009] A construction method for a semi-precast and semi-cast-in-place concrete bridge structure includes the following steps: Step 1: Pour concrete for the bridge piers. After the concrete reaches a certain strength, use a truck crane to lift the precast beams. Step 2: After all the precast beams have been hoisted, pass through the pre-drilled holes in the formwork support on the precast beams with through-steel pipes to form a horizontal crossbeam. Install the bottom formwork of the bridge deck panel on the horizontal crossbeam. Step 3: After the bottom formwork of the bridge deck is installed, install the bridge deck reinforcement on the bottom formwork, and then install the side formwork of the bridge deck. Step 4: Pour concrete into the bridge deck to form the deck concrete; Step 5: After the bridge deck concrete has reached a certain strength, remove the formwork of the bridge deck. Compared with existing technologies, this invention has the following advantages: This invention employs a semi-precast, semi-cast-in-place concrete bridge structure and construction method. It utilizes a structure of multiple precast beams stacked on top of a cast-in-place bridge deck, reducing the weight of the bridge during hoisting. No large cranes are needed; a commonly used 25T truck crane can be used to hoist the precast beams. For the cast-in-place bridge deck, pre-drilled holes in the precast beam web formwork support allow for the insertion of through-steel pipes as horizontal crossbeams to support the bottom formwork of the bridge deck, solving the problem of not being able to erect support frames under the bridge. Furthermore, this invention utilizes the beam stirrups at the top of the precast beams extending into the bridge deck concrete, making the bridge a unified whole and improving its load-bearing capacity. This method has low construction difficulty, reduces construction costs, and minimizes safety risks. Attached Figure Description

[0010] Figure 1 This is a longitudinal section view of a semi-precast and semi-cast-in-place concrete bridge structure according to the present invention. Figure 2 for Figure 1 Schematic diagram of the cross-sectional structure of the middle AA section; Figure 3 This is a diagram showing the steel reinforcement distribution of a semi-precast and semi-cast-in-place concrete bridge structure according to the present invention. Figure 4 This is a schematic diagram of the internal structure of a semi-precast and semi-cast-in-place concrete bridge structure according to the present invention.

[0011] In the diagram: 1. Precast beam; 2. Bridge deck support hole; 3. Bridge deck; 4. Pier; 5. Construction joint; 6. Longitudinal reinforcement of bridge deck; 7. Distribution reinforcement of bridge deck; 8. Stirrups of bridge deck; 9. Longitudinal reinforcement of beam web; 10. Beam stirrups; 11. Longitudinal reinforcement of beam bottom; 12. Reserved hole for formwork support; 13. Square timber; 14. Plywood; 15. Concrete deck; 16. Adjusting wooden blocks; 17. Through-hole steel pipe. Detailed Implementation

[0012] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0013] See Figure 1 and Figure 2 This invention discloses a semi-precast and semi-cast-in-place concrete bridge structure, including a pier 4, on which multiple precast beams 1 are arranged. The multiple precast beams 1 are placed in parallel and spaced apart. A bridge deck 3 is provided on the top of the precast beams 1. A construction joint 5 is provided at the contact position between the bottom surface of the bridge deck 3 and the top of the precast beams 1. The precast beams 1 are precast in a prefabrication yard, and the bridge deck 3 is cast in-place on site. The bridge deck 3 is superimposed on the precast beams 1 and cast to form an integral concrete load-bearing structure of precast beams 1 and bridge deck 3.

[0014] See Figure 3 The precast beam 1 is equipped with beam stirrups 10. When the precast beam 1 is precast and poured, part of the beam stirrups 10 protrudes from the top of the beam. When the bridge deck 3 is poured on site, the beam stirrups 10 extend into the bridge deck 3. Then the bridge deck 3 is poured on site, so that the precast beam 1 and the bridge deck form an integral whole, making the bridge an integral whole and improving the bridge's load-bearing capacity.

[0015] Furthermore, the precast beam 1 is also provided with longitudinal reinforcement bars 9 on the waist and longitudinal reinforcement bars 11 on the bottom, and the bridge deck 3 is provided with longitudinal reinforcement bars 6, distribution bars 7, and stirrups 8.

[0016] Furthermore, the precast beam 1 is provided with a template support reserved hole 12. The template support reserved hole 12 is located at the waist position of the precast beam 1, and multiple template support reserved holes 12 are located at the same elevation position. The template support reserved hole 12 is penetrated by a through steel pipe 17. After the precast beam 1 is installed in the design position, the through steel pipe 17 is passed through the template support reserved hole 12, and the through steel pipe 17 is used as a horizontal crossbeam to support the bottom formwork of the bridge deck 3 concrete.

[0017] Further, see Figure 4 The bottom and sides of the bridge deck 3 are provided with square timber 13 and plywood 14. The bottom of the square timber 13 is provided with adjusting pad 16. The adjusting pad 16 is set on the horizontal crossbeam formed by the through steel pipe 17 and is used to support the bottom template of the bridge deck 3.

[0018] This invention also discloses a construction method for a semi-precast and semi-cast-in-place concrete bridge structure, comprising the following steps: Step 1: Concrete is poured for pier 4. After the concrete of pier 4 reaches a certain strength, a truck crane is used to lift the precast beam 1. Step 2: After all the precast beams 1 are hoisted, the steel pipes 17 are passed through the pre-reserved holes 12 of the template support on the precast beams 1 to form a horizontal crossbeam. The bottom template of the bridge deck 3 is then installed on the horizontal crossbeam. Step 3: After the bottom formwork of bridge deck 3 is installed, install the reinforcing bars of bridge deck 3 on the bottom formwork, and then install the side formwork of bridge deck 3; Step 4: Pour concrete into bridge deck 3 to form deck concrete 15; Step 5: After the concrete of bridge deck 3 has reached a certain strength, remove the formwork of bridge deck 3.

[0019] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0020] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A semi-precast and semi-cast-in-place concrete bridge structure, characterized in that: The bridge includes a pier (4), on which multiple precast beams (1) are set. The multiple precast beams (1) are placed in parallel and spaced apart. A bridge deck (3) is set on the top of the precast beams (1). A construction joint (5) is set at the contact position between the bottom surface of the bridge deck (3) and the top of the precast beams (1). A template support reserved hole (12) is set on the precast beams (1). Through the template support reserved hole (12) is a through steel pipe (17). Multiple through steel pipes (17) form a horizontal crossbeam.

2. The semi-precast and semi-cast-in-place concrete bridge structure according to claim 1, characterized in that: The precast beam (1) is provided with beam stirrups (10), and the top part of the beam stirrups (10) extends into the bridge deck (3).

3. A semi-precast and semi-cast-in-place concrete bridge structure according to claim 1, characterized in that: The precast beam (1) is also provided with longitudinal reinforcement (9) on the waist and longitudinal reinforcement (11) on the bottom. The bridge deck (3) is provided with longitudinal reinforcement (6), distribution reinforcement (7) and stirrups (8).

4. A semi-precast and semi-cast-in-place concrete bridge structure according to claim 1, characterized in that: The pre-reserved holes (12) of the template support are set at the waist of the precast beam (1), and multiple pre-reserved holes (12) of the template support are set at the same elevation.

5. A semi-precast and semi-cast-in-place concrete bridge structure according to claim 1, characterized in that: The bottom and sides of the bridge deck (3) are provided with square timber (13) and plywood (14). The bottom of the square timber (13) is provided with adjusting pads (16), which are placed on the horizontal crossbeam formed by the through steel pipes (17).

6. A construction method for a semi-precast and semi-cast-in-place concrete bridge structure according to claim 1, comprising the following steps: Step 1: Concrete is poured for the pier (4). After the concrete of the pier (4) reaches a certain strength, a truck crane is used to lift the precast beam (1). Step 2: After all the precast beams (1) are hoisted, the steel pipes (17) are passed through the pre-reserved holes (12) of the template support on the precast beams (1) to form a horizontal crossbeam. The bottom template of the bridge deck (3) is installed on the horizontal crossbeam. Step 3: After the bottom formwork of the bridge deck (3) is installed, install the reinforcing steel bars of the bridge deck (3) on the bottom formwork, and then install the side formwork of the bridge deck (3); Step 4: Pour concrete into the bridge deck (3) to form the deck concrete (15). Step 5: After the concrete of the bridge deck (3) reaches a certain strength, remove the formwork of the bridge deck (3).

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