Concrete laminated slab-concrete box type composite beam bridge structure and construction method thereof

Abstract

The invention relates to the technical field of composite beam bridge structures, in particular to a concrete laminated slab-concrete box type composite beam bridge structure and a construction method thereof. According to the technical scheme, the structure comprises a precast concrete box beam and a concrete precast slab located at the upper end of the precast concrete box beam, and additional steel bars are arranged at the upper ends of the two sides of the precast concrete box beam; the structure further comprises a post-cast reinforced concrete layer and a cantilever construction supporting assembly. And the post-cast reinforced concrete layer is arranged above the precast concrete box beam and the concrete precast slab. According to the prefabricated concrete box beam, only a part of supports are reserved on the upper flange of the prefabricated concrete box beam and used for erecting the prefabricated concrete planks and placing additional steel bars, and compared with a traditional prefabricated box beam, the self weight of a prefabricated beam body is reduced; a slotted concrete precast slab technology is adopted, overhanging steel bars at the plate end of a traditional precast slab are omitted, position conflicts between the overhanging steel bars and between the overhanging steel bars and U-shaped joint bars are avoided, the steel bar consumption is low, the installation efficiency is high, and the overall durable effect is improved.

Description

Technical Field

[0001] The present application relates to the technical field of composite beam bridge structures, and in particular to a concrete composite slab-concrete box-type composite beam bridge structure and a construction method thereof. Background Art

[0002] Concrete box composite beam bridge is a bridge type with concrete box beam as the main load-bearing structure. This type of bridge is usually composed of concrete top and bottom plates, webs and diaphragms, forming a closed or semi-closed box structure. The composite box beam is a new type of bridge structure, an improvement on the traditional concrete bridge. Concrete box composite beam bridge structure has been widely used in highway and urban bridges, especially in the construction of large-span bridges, and has significant advantages.

[0003] The concrete composite slab-concrete box-type composite beam bridge structure applies the concrete composite slab to the superstructure (bridge deck structure) of the concrete box-type composite beam, which can further bring out the advantages of both.

[0004] The existing concrete box beam has a relatively complex supporting structure, a large weight, and complex construction and installation steps. In addition, there are external stirrups on the top of the beam. The pull-out and shear resistance of the entire beam body is not ideal, and it occupies a large space, which is not conducive to transportation and installation. Therefore, the present application proposes a concrete composite slab-concrete box composite beam bridge structure and a construction method thereof. Summary of the invention

[0005] The purpose of this application is to address the technical problems pointed out in the background technology and to propose a concrete composite slab-concrete box-type composite beam bridge structure and a construction method thereof.

[0006] On the one hand, the technical solution of the present application: a concrete composite slab-concrete box composite beam bridge structure, comprising a precast concrete box beam and a precast concrete slab located at the upper end thereof, wherein the upper ends of both sides of the precast concrete box beam are provided with additional steel bars;

[0007] It also includes post-cast reinforced concrete layers and cantilever construction support components;

[0008] The post-cast reinforced concrete layer is arranged above the precast concrete box beam and the precast concrete slab;

[0009] The cantilever construction support assembly is arranged on the outer sides of the precast concrete box beams on both sides.

[0010] Preferably, the cross-section of the precast concrete box beam is open, and vertical notches are provided on the upper parts of the upper flanges on both sides of the precast concrete box beam.

[0011] Preferably, the ends of the precast concrete panels are provided with panel end notches, and the top surfaces of the precast concrete panels are roughened and provided with shear reinforcements;

[0012] The end of the precast concrete panel is overlapped on the upper flange of the precast concrete box beam.

[0013] Preferably, the additional steel bars include U-shaped dowel bars and plate end notch steel bars, the U-shaped dowel bars are inserted into the vertical notches on the upper part of the upper flange of the precast concrete box beam and extend into the post-cast concrete layer, and the plate end notch steel bars are arranged between the plate end notches of adjacent concrete precast panels.

[0014] Preferably, the post-cast reinforced concrete layer includes post-cast layer steel bars and post-cast layer concrete. After the post-cast layer concrete solidifies, the post-cast reinforced concrete layer is combined with the precast concrete box beam, the precast concrete slab, and the additional steel bars to form a whole and jointly bear the force.

[0015] Preferably, the cantilever construction support assembly includes a support plate arranged on the side wall of the precast concrete box beam, the support plate is pre-anchored on the outer side web of the precast concrete box beam side beam by bolts, and the side wall of the support plate is connected to the support plate by a plurality of diagonal braces.

[0016] Preferably, the top of the support plate is kept horizontal, and the support plate and the top of the upper flange of the precast concrete box beam are at the same elevation.

[0017] Preferably, a transverse connecting member is connected between two adjacent precast concrete box beams, and the transverse connecting member includes a pre-anchored end plate connected to the side walls of the two adjacent precast concrete box beams, and the close sides of the two pre-anchored end plates are connected to the transverse connecting beam through a splicing plate.

[0018] On the other hand, the present application discloses a construction method of a concrete composite slab-concrete box-type composite beam bridge structure, comprising the following steps:

[0019] S1. Set up temporary supports, hang precast concrete box beams, and construct transverse connecting beams;

[0020] S2. Insert U-shaped dowel bars into the vertical notches;

[0021] S3. Erect cantilever construction support components, hang precast concrete slabs and erect them between the upper flange ends of precast concrete box beams, or erect them between the upper flange ends of precast concrete box beams and cantilever construction support components, and closely fit several precast concrete slabs along the bridge direction without leaving any gaps;

[0022] S4, placing plate end notch steel bars inside the plate end notches of the precast concrete plate;

[0023] S5, processing the post-casting layer steel bars at the predetermined positions on the tops of the precast concrete box beams and precast concrete slabs, and then pouring the post-casting layer concrete to form a post-casting reinforced concrete layer;

[0024] S6. After the concrete reaches the required strength, remove the temporary support.

[0025] Compared with the prior art, this application has the following beneficial technical effects:

[0026] In the present application, only a part of the support is retained on the upper flange of the precast concrete box beam for erecting the precast concrete slab and placing additional steel bars. Compared with the traditional precast box beam, the self-weight of the precast beam is reduced; and the slotted concrete precast slab technology is adopted to eliminate the protruding steel bars (beard bars) at the ends of the traditional precast slabs, thereby avoiding conflicts between the protruding steel bars and between the protruding steel bars and the U-shaped dowel bars. The structure is simple, the steel bar consumption is low, and the installation efficiency is high.

[0027] In this application, the precast concrete slab is used as the bottom formwork for the construction of the cast-in-place concrete layer, which reduces the amount of formwork and support engineering; the cast-in-place layer can also serve as a leveling layer, and there is no need to pave a concrete leveling layer on the top surface of the bridge, which reduces the amount of materials used and reduces the deadweight of the structure; the precast concrete slab is placed on the precast beam body (precast concrete box beam body), and after the construction of the post-cast layer is completed, the joints between the new and old concrete avoid the key sections of the slab that are subjected to bending and shearing, avoiding the problem of cracking of wet joints under long-term wheel loads.

[0028] The bridge deck structure in the present application adopts the form of concrete composite slabs. Compared with precast box girders that are only cast after hanging formwork at wet joints, the post-cast concrete of the composite slabs can connect the precast concrete box girders, precast concrete slabs and additional steel bars into a whole, and the integrity of the entire bridge is better; the extended stirrups on the top of the beam are eliminated and replaced with U-shaped inserted bars installed later, which avoids the stirrups of the beam body serving as both the vertical shear resistance of the beam body and the pull-out and shear resistance of the precast-post-cast horizontal interface, so that the pull-out and shear resistance of the horizontal interface can be designed specifically according to the force characteristics; at the same time, the elimination of the extended stirrups reduces the space occupied by the precast beam body, which is convenient for improving storage and transportation efficiency and is more convenient to install. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a three-dimensional diagram of a concrete composite slab-concrete box-type composite beam bridge structure;

[0030] Figure 2 It is the front view of the concrete composite slab-concrete box-type composite beam bridge structure;

[0031] Figure 3 It is a schematic diagram of the structure of the horizontal connection member in this application;

[0032] Figure 4 It is a structural schematic diagram of the precast concrete box beam in this application;

[0033] Figure 5 It is a schematic diagram of the connection structure between the precast concrete box beam and the transverse connecting member in this application;

[0034] Figure 6 It is a schematic diagram of the connection structure between the cantilever construction support assembly and the precast concrete box beam in this application;

[0035] Reference numerals: 1, precast concrete box beam; 21, precast concrete slab; 22, slab end notch; 23, shear reinforcement;

[0036] 4. Post-cast reinforced concrete layer; 5. Additional reinforcement; 31. Slab end notch reinforcement; 32. U-shaped dowel bars; 33. Vertical notch;

[0037] 6. Cantilever construction support assembly; 61. Support plate; 62. Diagonal brace; 63. Bolt;

[0038] 7. Transverse connecting piece; 71. Transverse connecting beam; 72. Spliced ​​plate; 73. Pre-anchored end plate. DETAILED DESCRIPTION

[0039] The technical solution of the present application is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0040] The components of the embodiments of the present application generally described and shown in the drawings herein may be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed, but merely represents the selected embodiments of the present application.

[0041] Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making any creative work shall fall within the scope of protection of this application.

[0042] In the description of the present application, it should be noted that the terms "upper", "lower", "inner", "outer", "front end", "rear end", "two ends", "one end", "the other end" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0043] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0044] Embodiment 1

[0045] like Figure 1-6 As shown, the concrete composite slab-concrete box composite beam bridge structure proposed in the present application comprises a precast concrete box beam 1 and a concrete precast slab 21 located at the upper end thereof, the end of the concrete precast slab 21 is provided with a plate end notch 22, the top surface of the concrete precast slab 21 is roughened and provided with shear reinforcement 23, wherein the end of the concrete precast slab 21 is overlapped on the upper flange of the precast concrete box beam 1. Additional reinforcement 5 is provided at the upper ends of both sides of the precast concrete box beam 1; the cross section of the precast concrete box beam 1 is an open type, and vertical notches 33 are provided at the upper parts of the upper flanges on both sides of the precast concrete box beam 1. Among them, only a part of the support is retained on the upper flange of the precast concrete box beam 1, which is used to set up the precast concrete slab 21 and place the additional reinforcement 5, which reduces the dead weight of the precast beam body compared with the traditional precast box beam. The slotted concrete precast panel technology is adopted to eliminate the protruding steel bars at the end of the traditional precast panel, avoiding the position conflicts between the protruding steel bars and the protruding steel bars and the U-shaped inserted bars. The structure is simple, the steel bar usage is low, and the installation efficiency is high. Among them, the precast concrete panel 21 can be used as the bottom formwork for the construction of the cast-in-place concrete layer, reducing the template and support engineering workload; the cast-in-place layer can also serve as the leveling layer, and there is no need to pave the concrete leveling layer on the top surface of the bridge, which reduces the material usage and reduces the deadweight of the structure.

[0046] It also includes a post-cast reinforced concrete layer 4 and a cantilever construction support assembly 6.

[0047] Specifically, the post-cast reinforced concrete layer 4 is arranged above the precast concrete box beam 1 and the precast concrete slab 21; the precast concrete slab 21 is placed on the beam body of the precast concrete box beam 1. After the post-cast layer is constructed, the joint between the new and old concrete avoids the key section of the slab that is subjected to bending and shearing, avoiding the cracking problem of the wet joint under the action of long-term wheel load. The cantilever construction support assembly 6 is arranged on the outside of the precast concrete box beam 1 on both sides.

[0048] In this embodiment, the additional steel bars 5 include U-shaped dowel bars 32 and plate end notch steel bars 31. The U-shaped dowel bars 32 are inserted into the vertical notches 33 on the upper part of the upper flange of the precast concrete box beam 1 and extend into the post-cast concrete layer 4. The plate end notch steel bars 31 are arranged between the plate end notches 22 of adjacent concrete precast panels 21 to ensure the stability of the support.

[0049] Furthermore, the post-cast reinforced concrete layer 4 includes post-cast layer steel bars and post-cast layer concrete. After the post-cast layer concrete solidifies, the post-cast reinforced concrete layer 4 is combined with the precast concrete box beam 1, the precast concrete slab 21, and the additional steel bars 5 to form a whole and jointly participate in the force bearing.

[0050] Specifically, the cantilever construction support assembly 6 includes a support plate arranged on the side wall of the precast concrete box beam 1, the support plate is pre-anchored on the outer side web of the side beam of the precast concrete box beam 1 through bolts 63, and the side wall of the support plate is connected to a support plate 61 through a plurality of diagonal braces 62. The top of the support plate 62 is kept horizontal, and the support plate 62 and the top of the upper flange of the precast concrete box beam 1 are at the same elevation.

[0051] In this embodiment, a transverse connecting member 7 is connected between two adjacent precast concrete box beams 1. Specifically, the transverse connecting member 7 includes a pre-anchored end plate 73 connected to the side walls of the two adjacent precast concrete box beams 1, and the two pre-anchored end plates 73 are connected to a transverse connecting beam 71 on one side thereof through a splicing plate 72. The transverse connecting beam 71 is used as a connecting member between the precast concrete box beams 1 at the transverse connecting position, wherein the pre-anchored end plate 73 is embedded in the precast concrete box beam 1 by bolts during the prefabrication stage in the factory, and is bolted to the transverse connecting beam 71 through the splicing plate 72, which can improve the lateral stiffness and integrity of the concrete box beam 1 during the construction and use stages.

[0052] In summary, in this application, the precast concrete slab 21 is placed on the precast beam body (precast concrete box beam body). After the construction of the post-casting layer is completed, the joints between the new and old concrete avoid the key sections of the slab that are subjected to bending and shearing, avoiding the cracking problem of the wet joints under the action of long-term wheel loads. The bridge deck structure adopts the form of a concrete composite slab. Compared with the precast box beam that is only cast after hanging the mold at the wet joint, the post-cast concrete of the composite slab can connect the precast concrete box beam 1, the precast concrete slab 21 and the additional steel bars 5 into a whole, and the integrity of the whole bridge is better. In this application, a precast concrete box beam 1 is adopted, and the extended stirrups at the top of the beam are cancelled and replaced by the U-shaped inserted bars 32 installed later, so as to avoid the stirrups of the beam body serving as the vertical shear resistance of the beam body and the pull-out and shear resistance of the precast-post-casting horizontal interface, so that the pull-out and shear resistance of the horizontal interface can be designed according to the force characteristics; at the same time, the cancellation of the extended stirrups reduces the space occupied by the precast beam body, which is convenient for improving the storage and transportation efficiency.

[0053] Embodiment 2

[0054] Based on the first embodiment, a construction method of a concrete composite slab-concrete box-type composite beam bridge structure is proposed, comprising the following steps:

[0055] S1, erect temporary supports, hang precast concrete box beam 1, and construct transverse connecting beam 71;

[0056] S2, inserting the U-shaped dowel bar 32 into the vertical notch 33;

[0057] S3, erecting a cantilever construction support assembly 6, hanging a precast concrete slab 21 and erecting it between the upper flange ends of the precast concrete box beam 1, or erecting it between the upper flange ends of the precast concrete box beam 1 and the cantilever construction support assembly 6, and a plurality of precast concrete slabs 21 are closely joined along the bridge direction without leaving any gaps;

[0058] S4, placing the plate end notch steel bars 31 inside the plate end notch 22 of the precast concrete plate 21;

[0059] S5, processing the post-cast layer steel bars at the predetermined positions on the tops of the precast concrete box beam 1 and the precast concrete slab 21, and then pouring the post-cast layer concrete to form a post-cast reinforced concrete layer 4;

[0060] S6. After the concrete has been formed and reached sufficient strength, the temporary support shall be removed.

[0061] The above-mentioned specific embodiments are merely preferred embodiments of the present application. Based on the technical solutions of the present application and the relevant inspirations of the above-mentioned embodiments, those skilled in the art may make various alternative improvements and combinations to the above-mentioned specific embodiments. The above-mentioned specific embodiments are merely explanations of the present application, and they are not limitations of the present application.

Claims

1. Concrete composite slab-concrete box composite beam bridge structure, characterized in that: It comprises a precast concrete box beam (1) and a precast concrete slab (21) located at the upper end thereof, wherein the upper ends of both sides of the precast concrete box beam (1) are provided with additional steel bars (5); It also includes a post-cast reinforced concrete layer (4) and a cantilever construction support assembly (6); The post-cast reinforced concrete layer (4) is arranged above the precast concrete box beam (1) and the precast concrete slab (21); The cantilever construction support assembly (6) is arranged on the outside of the precast concrete box beam (1) on both sides.

2. The concrete composite slab-concrete box-type composite beam bridge structure according to claim 1 is characterized in that: The cross section of the precast concrete box beam (1) is an open type, and vertical notches (33) are provided on the upper parts of the upper flanges on both sides of the precast concrete box beam (1).

3. The concrete composite slab-concrete box-type composite beam bridge structure according to claim 2 is characterized in that: The end of the precast concrete panel (21) is provided with a panel end notch (22), and the top surface of the precast concrete panel (21) is roughened and provided with shear-resistant steel bars (23); The end of the precast concrete panel (21) is overlapped on the upper flange of the precast concrete box beam (1).

4. The concrete composite slab-concrete box-type composite beam bridge structure according to claim 3 is characterized in that: The additional reinforcement (5) comprises a U-shaped inserted reinforcement (32) and a plate end notch reinforcement (31), wherein the U-shaped inserted reinforcement (32) is inserted into a vertical notch (33) at the upper part of the upper flange of the precast concrete box beam (1) and extends into the post-cast concrete layer (4), and the plate end notch reinforcement (31) is arranged between the plate end notches (22) of adjacent concrete precast panels (21).

5. The concrete composite slab-concrete box-type composite beam bridge structure according to claim 1, characterized in that: The post-cast reinforced concrete layer (4) comprises post-cast layer steel bars and post-cast layer concrete. After the post-cast layer concrete solidifies, the post-cast reinforced concrete layer (4) is combined with the precast concrete box beam (1), the precast concrete slab (21), and the additional steel bars (5) to form a whole and participate in the force bearing together.

6. The concrete composite slab-concrete box-type composite beam bridge structure according to claim 5, characterized in that: The cantilever construction support assembly (6) comprises a support plate arranged on the side wall of the precast concrete box beam (1), the support plate being pre-anchored on the outer side web of the precast concrete box beam (1) through bolts (63), and the side wall of the support plate being connected to a support plate (61) through a plurality of diagonal braces (62).

7. The concrete composite slab-concrete box-type composite beam bridge structure according to claim 6, characterized in that: The top of the support plate (62) is kept horizontal, and the support plate (62) and the top of the upper flange of the precast concrete box beam (1) are located at the same elevation.

8. The concrete composite slab-concrete box-type composite beam bridge structure according to claim 4, characterized in that: A transverse connecting member (7) is connected between two adjacent precast concrete box beams (1), and the transverse connecting member (7) comprises a pre-anchored end plate (73) connected to the side walls of the two adjacent precast concrete box beams (1), and the adjacent sides of the two pre-anchored end plates (73) are connected to a transverse connecting beam (71) via a splicing plate (72).

9. The construction method of the concrete composite slab-concrete box-type composite beam bridge structure according to claim 8, characterized in that: The following steps are involved: S1, erecting temporary supports, hanging and placing precast concrete box beams (1), and constructing transverse connecting beams (71); S2, inserting the U-shaped dowel bar (32) into the vertical notch (33); S3, erecting a cantilever construction support assembly (6), hanging and placing a precast concrete (21) slab between the upper flange ends of the precast concrete box beam (1), or between the upper flange ends of the precast concrete box beam (1) and the cantilever construction support assembly (6), and a plurality of precast concrete slabs (21) are closely joined along the bridge direction without leaving any gaps; S4, placing a plate end notch steel bar (31) inside the plate end notch (22) of the precast concrete plate (21); S5, processing the post-casting layer steel bars at predetermined positions on the tops of the precast concrete box beam (1) and the precast concrete slab (21), and then pouring the post-casting layer concrete to form a post-casting reinforced concrete layer (4); S6. After the concrete reaches the required strength, remove the temporary support.

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