UHPC shell and CSW steel inner core full-prefabricated box type cover beam

Abstract

The utility model discloses a UHPC (Ultra High Performance Concrete) shell-CSW steel inner core full-prefabricated box type cover beam which is of a hollow box type structure and comprises a UHPC shell and a rectangular steel inner core, and the steel inner core comprises a corrugated steel web, a straight steel top plate, a straight steel bottom plate and a plurality of stiffening steel pipes which are vertically arranged. One end of the stiffening steel pipe penetrates through the straight steel top plate and is connected with the straight steel top plate into a whole, the other end of the stiffening steel pipe penetrates through the straight steel bottom plate and is connected with the straight steel bottom plate into a whole, and a stiffening steel pipe concrete column connected with the UHPC shell into a whole is poured in the stiffening steel pipe. The corrugated steel webs and the stiffening steel pipes are arranged, so that the buoyancy generated by the UHPC to the steel inner core during pouring is reduced, the overall stability is improved, the top plate and the bottom plate are better stressed cooperatively, deformation of the steel inner core caused by shrinkage of the UHPC is reduced, and the integrity and stability of the capping beam structure are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of bridge engineering, in particular to a fully prefabricated box-type cap beam with a UHPC shell and a CSW steel inner core. Background Art

[0002] The cap beam is an important component of the bridge structure, connecting the upper and lower structures of the bridge. With the development of viaducts and the increase in traffic volume, the large cantilever cap beam structure is becoming more and more widely used. And assembly construction is in response to the development trend of national policies, but the existing cap beam structure is heavy, the construction is complex, the impact on traffic is large, and it is difficult to achieve assembly construction. The weight of an ordinary large cantilever prestressed concrete cap beam can reach 600 tons, and prefabrication and hoisting are difficult and inconvenient to transport. Therefore, ordinary concrete cap beams are mostly cast on site or prefabricated in sections. For on-site casting construction, a series of processes such as installing full-floor brackets, erecting formwork, pouring, tensioning prestress, maintenance, and demolding are required. The construction steps are cumbersome and the construction time is long, which has a great impact on the surrounding environment and traffic; for prefabricated construction in sections, although the construction period is short and the impact on surrounding traffic is small, brackets are still required to maintain the segmented beam sections, and the construction level requirements are also high. In order to reduce the self-weight of the cap beam, the existing schemes mostly hollow out its interior, but the hollowing out of the interior has high process requirements, and there are problems such as difficulty in removing the internal formwork and low shear resistance.

[0003] In order to solve the above problems, patent document CN219653489U discloses a fully prefabricated steel-UHPC cap beam structure and its beam-column combination, and proposes an internally hollow box-type cap beam structure, including an outer UHPC structure and an inner steel structure inner membrane, which can greatly reduce the deadweight and reduce the demand for transportation and construction equipment. However, when the inner steel structure inner membrane is used as the inner membrane plate to cast the outer UHPC, the UHPC will generate a large secondary internal force when it shrinks, which can easily cause the steel plate of the inner steel structure inner membrane to deform, affecting the structural stability of the cap beam. Utility Model Content

[0004] The technical problem to be solved by the utility model is to overcome the deficiencies of the prior art and provide a UHPC shell-CSW steel inner core fully prefabricated box-type cap beam with better structural stability.

[0005] In order to solve the above technical problems, the utility model adopts the following technical solutions:

[0006] A UHPC shell-CSW steel core fully prefabricated box-type cap beam, the cap beam is an internally hollow box-type structure, including a UHPC shell and a rectangular steel core, the steel core includes a corrugated steel web, a straight steel top plate, a straight steel bottom plate and a plurality of vertically arranged stiffening steel pipes, one end of the stiffening steel pipe passes through the straight steel top plate and is connected to the straight steel top plate as a whole, and the other end passes through the straight steel bottom plate and is connected to the straight steel bottom plate as a whole, and a stiffening steel tube concrete column connected to the UHPC shell is cast in the stiffening steel pipe.

[0007] As a further improvement of the above solution:

[0008] A plurality of support pads are evenly distributed on the upper surface of the cap beam, and the stiffening steel pipe is arranged below each support pad.

[0009] The reinforcing steel pipe is a square pipe, and the cross section of the reinforcing steel pipe is substantially the same as the cross section of the support pad stone.

[0010] The support pads are symmetrically distributed in two rows along the width direction of the cap beam, and the side walls of the stiffening steel pipes are tightly attached to the corrugated steel web.

[0011] The stiffening steel pipe extends out of the straight steel top plate or the straight steel bottom plate by at least 100 mm and is located in the UHPC shell.

[0012] The outer surface of the steel inner core is provided with shear nails which are anchored to the UHPC shell.

[0013] The cap beam is a cantilever cap beam, and the fixed support ends of the straight steel top plate and the straight steel bottom plate are thickened relative to the free end of the cantilever.

[0014] Prestressed steel bars are arranged in the top plate of the UHPC shell.

[0015] Compared with the prior art, the advantages of the utility model are:

[0016] The utility model proposes a UHPC shell-CSW steel core fully prefabricated box-type cap beam, the steel core web adopts a corrugated steel web, the corrugated steel web has strong anti-buckling ability, good stability, and high rigidity, so that the structural force is clear, the overall rigidity is enhanced, the secondary internal force generated by the shrinkage of UHPC is reduced, and the anti-buckling ability of the steel core web is improved. The stiffening steel pipe runs through the straight steel top plate and the straight steel bottom plate, and is welded together with them. UHPC will be poured into the stiffening steel pipe to form a stiffened steel tube concrete column, which can reduce the buoyancy generated by UHPC on the steel core during pouring, improve the overall stability, and make the straight steel top plate and the straight steel bottom plate better coordinated in force, further reduce the deformation of the steel core caused by the shrinkage of UHPC, and improve the integrity and stability of the cap beam structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic structural cross-sectional diagram of a fully prefabricated box-type cap beam of a UHPC shell and a CSW steel inner core in an embodiment.

[0018] Figure 2 yes Figure 1 Cross-sectional view at AA in the middle.

[0019] Figure 3 yes Figure 1 Cross-sectional view at BB in the middle.

[0020] The symbols in the figure represent:

[0021] 1. UHPC shell; 2. Corrugated steel web; 3. Prestressed steel bars; 4. Support pad stone; 5. Bridge pier; 6. Reinforced steel pipe; 61. Reinforced steel tube concrete column; 7. Straight steel top plate; 8. Shear nails; 9. Straight steel bottom plate. DETAILED DESCRIPTION

[0022] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0023] Figures 1 to 3 An embodiment of a UHPC shell-CSW steel core fully prefabricated box-type cap beam of the utility model is shown. The cap beam is a box-type structure with a hollow interior, including a UHPC shell 1 and a rectangular steel core. The steel core includes a corrugated steel web 2, a straight steel top plate 7, a straight steel bottom plate 9, and a plurality of vertically arranged stiffening steel pipes 6. One end of the stiffening steel pipe 6 passes through the straight steel top plate 7 and is connected to the straight steel top plate 7 as a whole, and the other end passes through the straight steel bottom plate 9 and is connected to the straight steel bottom plate 9 as a whole. A stiffening steel tube concrete column 61 connected to the UHPC shell 1 is cast in the stiffening steel pipe 6. In this structure, the steel core web adopts a corrugated steel web 2, so that the structure is clearly stressed, the overall rigidity is enhanced, the secondary internal force generated by the shrinkage of UHPC is reduced, and the buckling resistance of the steel core web is improved. The stiffening steel pipe 6 passes through the straight steel top plate 7 and the straight steel bottom plate 9 and is welded therewith as a whole. UHPC will be poured into the stiffening steel pipe 6 to form a stiffened steel tube concrete column 61, which can reduce the buoyancy of the UHPC on the steel inner core during pouring, improve the overall stability, enable the top and bottom plates to better coordinate the force, reduce the deformation of the steel inner core caused by the shrinkage of UHPC, and improve the integrity and stability of the cap beam structure.

[0024] In this embodiment, a plurality of support pads 4 are evenly distributed on the upper surface of the cap beam, and the stiffening steel pipe 6 is arranged below each support pad 4. Through this structure, the force above the support can be better transmitted to the bottom plate.

[0025] In this embodiment, the support pedestal 4 is symmetrically distributed in two rows along the width direction of the cap beam, and the side wall of the stiffening steel pipe 6 is closely attached to the corrugated steel web 2. Through this structure, after the UHPC shell 1 is cast, the stiffening steel pipe 6 can provide lateral support to the corrugated steel web 2 of the steel core, further reducing the deformation of the steel plate caused by the shrinkage of the UHPC.

[0026] In this embodiment, the stiffening steel pipe 6 is a square pipe, and the cross section of the stiffening steel pipe 6 is roughly the same as the cross section of the support pedestal 4. Through this structure, the stiffening steel pipe 6 can provide a larger lateral support area for the corrugated steel web 2, thereby improving the support effect. The cross section of the stiffening steel pipe 6 can be similar to that of the support pedestal 4, thereby further reducing the overall deadweight of the cap beam while ensuring the support effect.

[0027] In this embodiment, the stiffening steel pipe 6 extends out of the straight steel top plate 7 or the straight steel bottom plate 9 by at least 100 mm and is located in the UHPC shell 1. Through this structure, the stiffening steel pipe 6 can be connected to the top and bottom plates of the cap beam UHPC to bear the force synergistically, better transmit the force from the top of the support, and enhance the integrity of the cap beam structure.

[0028] In this embodiment, shear studs 8 anchored to the UHPC shell 1 are arranged on the outer surface of the steel inner core.

[0029] In this embodiment, the cap beam is a large cantilever cap beam, the steel inner core is made of high-strength steel, and the cantilever ends of the straight steel top plate 7 and the straight steel bottom plate 9 are thickened relative to the cantilever free ends. In this structure, the corrugated steel web 2 has strong anti-buckling ability, good stability, and high rigidity, so that the cap beam of this application has a greater bearing capacity, good anti-buckling ability of the web, and a larger theoretical span, so that the cap beam structure of this embodiment can be applied to a large cantilever cap beam structure; the stability of the cap beam structure is further improved by thickening the fixed support ends of the straight steel top plate 7 and the straight steel bottom plate 9.

[0030] In this embodiment, prestressed steel bars 3 are arranged in the top plate of the UHPC shell 1. In this structure, because the top plate is subjected to the largest tensile stress in the large cantilever cap beam structure, prestressed steel bars 3 are arranged in the top plate of the UHPC shell 1 to further improve the stability of the cap beam structure.

[0031] The construction process of the UHPC shell-CSW steel core fully prefabricated box-type cap beam of the utility model may include the following steps:

[0032] Step 1: Use high-strength steel to make a steel core with a corrugated steel web 2, weld shear nails 8 on its outer surface, and make holes in its straight steel top plate 7 and straight steel top plate 7 at the bridge support position.

[0033] Step 2: Insert the stiffening steel pipe 6 at the opening of the steel inner core and weld it to penetrate the top and bottom plates of the steel inner core.

[0034] Step 3: Set up the outer formwork, pour UHPC between the outer formwork and the steel inner core, and pour UHPC into the steel tube to form a steel tube concrete reinforced structure.

[0035] Step 4: Tensioning the prestressed steel bars 3 in the UHPC.

[0036] Step 5: Transport the prefabricated large cantilever composite cap beam from the factory to the site and hoist it to the top of pier 5.

[0037] Step 6: Hoist the main beam on the cap beam.

[0038] The UHPC shell-CSW steel core fully prefabricated box-type cap beam of the utility model has light weight, high stability, good durability, convenient manufacturing and construction, high bearing capacity, and little impact on the surrounding environment and traffic. It conforms to the characteristics of assembly construction and can be mass-produced and promoted for application.

[0039] Although the present invention has been disclosed as a preferred embodiment as above, it is not intended to limit the present invention. Any technician familiar with the art can use the above disclosed technical content to make many possible changes and modifications to the technical solution of the present invention without departing from the scope of the technical solution of the present invention, or modify it into an equivalent embodiment of equivalent changes. Therefore, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention should fall within the scope of protection of the technical solution of the present invention.

Claims

1. A UHPC shell-CSW steel inner core fully prefabricated box-type cap beam, the cap beam is a box-type structure with a hollow interior, comprising a UHPC shell (1) and a rectangular steel inner core, Features: The steel inner core comprises a corrugated steel web (2), a straight steel top plate (7), a straight steel bottom plate (9) and a plurality of vertically arranged stiffening steel pipes (6); one end of the stiffening steel pipe (6) passes through the straight steel top plate (7) and is connected to the straight steel top plate (7) as a whole, and the other end passes through the straight steel bottom plate (9) and is connected to the straight steel bottom plate (9) as a whole; a stiffening steel tube concrete column (61) connected to the UHPC shell (1) is cast in the stiffening steel pipe (6).

2. The UHPC shell-CSW steel core fully prefabricated box cap beam according to claim 1, Features: A plurality of support pad stones (4) are evenly distributed on the upper surface of the cap beam, and the stiffening steel pipe (6) is arranged below each support pad stone (4).

3. The UHPC shell-CSW steel core fully prefabricated box cap beam according to claim 2, Features: The stiffening steel pipe (6) is a square pipe, and the cross section of the stiffening steel pipe (6) is substantially the same as the cross section of the support pad stone (4).

4. The UHPC shell-CSW steel core fully prefabricated box cap beam according to claim 3, Features: The support pad stones (4) are symmetrically distributed in two rows along the width direction of the cap beam, and the side walls of the stiffening steel pipes (6) are tightly attached to the corrugated steel webs (2).

5. The UHPC shell-CSW steel core fully prefabricated box cap beam according to claim 3, Features: The stiffening steel pipe (6) extends out of the straight steel top plate (7) or the straight steel bottom plate (9) by at least 100 mm and is located inside the UHPC shell (1).

6. The UHPC shell-CSW steel core fully prefabricated box cap beam according to claim 1, Features: The outer surface of the steel inner core is provided with shear studs (8) which are anchored to the UHPC shell (1).

7. The UHPC shell-CSW steel core fully prefabricated box cap beam according to claim 1, Features: The cap beam is a cantilever cap beam, and the fixed support ends of the straight steel top plate (7) and the straight steel bottom plate (9) are thickened relative to the free end of the cantilever.

8. The UHPC shell-CSW steel core fully prefabricated box cap beam according to claim 1, Features: Prestressed steel bars (3) are arranged in the top plate of the UHPC shell (1).

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