Prefabricated steel-concrete composite beam and construction method thereof

Abstract

This invention relates to the field of bridge construction technology, specifically to a precast steel-concrete composite beam and its construction method. A precast steel-concrete composite beam includes: a support section, mounted on a pier, comprising a first precast steel beam and a first precast concrete panel connected to each other, with a first stiffening plate near its end on the first bottom plate of the first precast steel beam; a side span section, comprising a second precast steel beam and a second precast concrete panel connected to each other, with a second stiffening plate near the end of the second bottom plate of the second precast steel beam near the end of the support section, the second stiffening plate extending to the outside of the second bottom plate to overlap with the first stiffening plate; and fasteners, penetrating the support section, the first stiffening plate, and the second stiffening plate to fix the support section and the side span section. This invention provides a precast steel-concrete composite beam and its construction method with high construction efficiency and minimal impact on traffic or waterways.

Description

Technical Field

[0001] This invention relates to the field of bridge construction technology, specifically to a precast steel-concrete composite beam and its construction method. Background Technology

[0002] Compared to reinforced concrete beams, steel-concrete composite beams can reduce structural self-weight, decrease cross-sectional dimensions, save on formwork and template work, shorten construction time, and increase beam ductility. Compared to steel beams, they can reduce steel consumption, increase stiffness, stability, and overall integrity. Steel-concrete composite beams effectively utilize the compressive strength of concrete and the tensile strength of steel. Due to their relatively long length, steel-concrete composite beams require segmentation during transportation and on-site erection, typically at the quarter-span mark. Temporary piers are needed at these segmentation points for steel beam erection, and these piers are generally only removed after the bridge deck concrete has been poured and reached its strength. These temporary piers bear part of the weight of the steel beams and bridge deck concrete and must possess sufficient stiffness; therefore, strong materials are required for their construction, making the foundation and main structure construction of the temporary piers labor-intensive and time-consuming. Furthermore, since the temporary piers are located at the quarter-span mark, they often encroach on roads or waterways beneath the bridge, significantly impacting traffic and the river environment. Summary of the Invention

[0003] Therefore, the technical problem to be solved by the present invention is to overcome the defects of low construction efficiency and significant impact on traffic or waterways in the existing steel-concrete composite beams, thereby providing a precast steel-concrete composite beam and its construction method with high construction efficiency and minimal impact on traffic or waterways.

[0004] To address the aforementioned technical problems, this invention provides a precast steel-concrete composite beam, comprising:

[0005] The support section, located on the pier, includes a first precast steel beam and a first precast concrete panel connected to each other, and a first stiffening plate is provided on the first bottom plate of the first precast steel beam near the end;

[0006] The side span includes a second precast steel beam and a second precast concrete panel that are connected to each other. The second bottom plate of the second precast steel beam is provided with a second stiffening plate at the end near the end of the support section. The second stiffening plate extends to the outside of the second bottom plate to overlap with the first stiffening plate.

[0007] Fasteners are provided through the support section, the first stiffening plate, and the second stiffening plate to secure the support section and the side span section.

[0008] Optionally, it also includes a mid-span section, which includes a third precast steel beam and a third precast concrete panel connected to each other. The third bottom plate of the third precast steel beam is provided with a third stiffening plate near its end. The third stiffening plate extends to the outside of the third bottom plate to overlap with the first stiffening plate.

[0009] Optionally, the first stiffening plate is a plurality of vertical plates spaced apart, and the second stiffening plate and the third stiffening plate are both U-shaped stiffening ribs, and the width of the U-shaped stiffening rib is less than the distance between two adjacent vertical plates, so that the second stiffening plate or the third stiffening plate overlaps between two adjacent first stiffening plates.

[0010] Optionally, the first web of the support section is provided with a first reinforcing plate, the first reinforcing plate extends horizontally outward, and the first reinforcing plate is provided with a first connecting member; the second web of the side span section is provided with a second reinforcing plate, the second reinforcing plate extends horizontally inward, and the second reinforcing plate is provided with a second connecting member; the third web of the middle span section is provided with a third reinforcing plate, the third reinforcing plate extends horizontally inward, and the third reinforcing plate is provided with a third connecting member.

[0011] A construction method for the aforementioned precast steel-concrete composite beam is also provided, comprising the following steps:

[0012] The first precast steel beam and the first precast concrete panel, the second precast steel beam and the second precast concrete panel are assembled respectively to form the support section and the side span section;

[0013] After the support section is fixed to the pier, the second stiffening plate of the side span is overlapped with the first stiffening plate of the support section.

[0014] Fasteners are then inserted through the support section, the first stiffening plate, and the second stiffening plate to secure the support section and the side span section.

[0015] Optionally, installation space is reserved at the ends of the first precast steel beam with the first stiffening plate and the second precast steel beam with the second stiffening plate. After the support section and the side span section are fixed by fasteners, the reserved top plate is assembled into the installation space.

[0016] Optionally, the installation space is 1 meter along the length of the composite beam.

[0017] Optionally, fastener mounting holes are provided on the support section, the first stiffening plate, and the second stiffening plate.

[0018] Optionally, after assembling the top plate, the third stiffening plate of the mid-span section is connected to the first stiffening plate of the support section and fixed with fasteners.

[0019] Optionally, the method also includes the step of assembling a reserved top plate into the installation space between the third precast steel beam and the first precast steel beam.

[0020] The technical solution of this invention has the following advantages:

[0021] 1. The precast steel-concrete composite beam provided by this invention has a support section and a side span section that are interconnected by a first stiffening plate and a second stiffening plate at the ends, and then fixed by fasteners. This eliminates the need for temporary piers; the support section is simply fixed to the existing piers, and then the side span section is connected to the support section. This reduces the construction of temporary piers, improves construction efficiency, saves raw materials, and reduces the impact on traffic or the river environment.

[0022] 2. The precast steel-concrete composite beam provided by the present invention has a U-shaped stiffening rib with a width smaller than the spacing between two adjacent vertical plates, so that the second or third stiffening plate overlaps between two adjacent first stiffening plates, further improving the connection reliability of the support section, the side span section and the middle span section.

[0023] 3. The precast steel-concrete composite beam provided by the present invention, with its first, second, and third connecting parts, ensures the strength and reliability of the connection between the precast steel beam and the precast concrete slab.

[0024] 4. The construction method of the precast steel-concrete composite beam provided by the present invention allows subsequent construction to proceed after the support plate is fixed to the original bridge pier with a temporary device. After the connection reaches the predetermined strength, the temporary device can be removed, which is convenient and efficient.

[0025] 5. The construction method of the precast steel-concrete composite beam provided by the present invention has reserved installation space at the ends of the first precast steel beam with a first stiffening plate and the second precast steel beam with a second stiffening plate, so as to facilitate the construction of the support section and the side span section. Attached Figure Description

[0026] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0027] Figure 1 A schematic diagram of the precast steel-concrete composite beam provided by the present invention;

[0028] Figure 2 This is a schematic diagram of the support section;

[0029] Figure 3 This is a schematic diagram of the side span segment;

[0030] Figure 4 This is a schematic diagram showing the overlapping of the support section and the side span section;

[0031] Figure 5 This is a schematic diagram showing the bolted connection between the support section and the side span section;

[0032] Figure 6 This is a schematic diagram of the support section from another angle;

[0033] Figure 7 This is a schematic diagram of another angle of the side span segment;

[0034] Figure 8 This is a schematic diagram from another angle after the support section and the side span section are bolted together;

[0035] Figure 9 for Figure 8 A schematic diagram after the pre-installed top plate is assembled.

[0036] Explanation of reference numerals in the attached figures:

[0037] 1. Support section; 2. Side span section; 3. First precast steel beam; 4. First precast concrete panel; 5. First stiffening plate; 6. First web plate; 7. Mounting hole; 8. Installation space; 9. Reserved top plate; 10. First reinforcing plate; 11. First connector; 12. Second precast steel beam; 13. Second precast concrete panel; 14. Second stiffening plate; 15. Second web plate; 16. Second reinforcing plate; 17. Second connector; 18. Fastener. Detailed Implementation

[0038] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. 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.

[0039] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0040] like Figures 1 to 9 The precast steel-concrete composite beam shown is implemented in one specific way, taking a three-span continuous beam as an example, including a central span, two support sections 1 located on both sides of the central span, and side span sections 2 located outside the two support sections 1.

[0041] The support section 1 is temporarily installed on the bridge pier and includes a first precast steel beam 3 and a first precast concrete panel 4 connected to each other. A first stiffening plate 5 is provided near the end of the first bottom plate of the first precast steel beam 3. The first stiffening plate 5 consists of multiple vertical plates spaced apart, with 3-4 plates spaced apart along the width direction of the first precast steel beam 3. The plate is 70cm long and its height is lower than the height of the first web plate 6 of the first precast steel beam 3. An additional steel plate is provided on the inner side of the first web plate 6 to increase the strength of the first web plate 6. Mounting holes 7 are reserved in the area extending 50cm inward from the ends of the first bottom plate and the first web plate 6.

[0042] An installation space 8 is reserved at the end of the first precast steel beam 3 where the first stiffening plate 5 is provided. The installation space 8 is 1 meter long along the length of the composite beam, and a reserved top plate 9 is installed in the installation space 8. The top of the first web plate 6 of the support section 1 is provided with a first reinforcing plate 10, which extends horizontally outward. The first reinforcing plate 10 is provided with a first connector 11, which is a shear stud, and the shear stud is welded to the first reinforcing plate 10.

[0043] The side span 2 includes a second precast steel beam 12 and a second precast concrete panel 13 connected to each other. A second stiffening plate 14 is provided at the end of the second bottom plate of the second precast steel beam 12 near the end of the supporting section 1. The second stiffening plate 14 is a U-shaped stiffening rib, the height of which is less than the height of the second web 15, and the width of which is less than the distance between two adjacent vertical plates, so that the second stiffening plate 14 overlaps between two adjacent first stiffening plates 5. An additional steel plate is provided on the inner side of the second web 15 to increase its strength.

[0044] The second stiffening plate 14 extends along the length direction to the outside of the second bottom plate to overlap with the first stiffening plate 5. The portion of the second stiffening plate 14 located inside the side span section 2 is welded to the second bottom plate and the second web plate 15. In order to further improve the connection strength, mounting holes 7 are reserved at the welding positions of the second stiffening plate 14 and the second bottom plate and the second web plate 15, as well as at the portion of the second stiffening plate 14 extending to the outside.

[0045] An installation space 8 is reserved at the end of the second precast steel beam 12 where the second stiffening plate 14 is provided. The installation space 8 is 1 meter long along the length of the composite beam, and a reserved top plate 9 is installed in the installation space 8. A second reinforcing plate 16 is provided on the second web of the side span section 2. The second reinforcing plate 16 extends horizontally inward, and a second connector 17 is provided on the second reinforcing plate 16. The second connector 17 is a shear stud, which is welded to the second reinforcing plate 16.

[0046] The mid-span section includes a third precast steel beam and a third precast concrete panel connected to each other. The third bottom plate of the third precast steel beam has a third stiffening plate near its end. This third stiffening plate is a U-shaped stiffening rib, the height of which is less than the height of the third web plate, and the width of which is less than the distance between two adjacent vertical plates. This allows the third stiffening plate to overlap between two adjacent first stiffening plates, i.e., its ends overlap two supporting sections respectively. An additional steel plate is provided on the inner side of the third web plate to increase its strength.

[0047] The third stiffening plate extends along the length direction to the outside of the third base plate to overlap with the first stiffening plate. The portion of the third stiffening plate located inside the mid-span section is welded to the third base plate and the third web plate. In order to further improve the connection strength, mounting holes are reserved at the welding positions of the third stiffening plate and the third base plate and the third web plate, as well as at the portion of the third stiffening plate extending to the outside.

[0048] An installation space is reserved at the end of the third precast steel beam where the third stiffening plate is located. The reserved space is 1 meter long along the length of the composite beam, and a reserved top plate is installed in the installation space. A third reinforcing plate is provided on the third web of the mid-span section. The third reinforcing plate extends horizontally inward and is provided with a third connector, which is a shear stud, and the shear stud is welded to the third reinforcing plate.

[0049] Fasteners 18 are provided through mounting holes 7 in the support section 1, the first stiffening plate 5 and the second stiffening plate 14, the side span section 2 and the second stiffening plate 14, and the middle span section and the third stiffening plate, to fix the support section 1 and the side span section 2.

[0050] A construction method for precast steel-concrete composite beams includes the following steps:

[0051] The first precast steel beam 3 and the first precast concrete panel 4, the second precast steel beam 12 and the second precast concrete panel 13, and the third precast steel beam and the third precast concrete panel are assembled by shear studs, and the installation space 8 of the reserved top plate 9 is reserved to form the support section 1, the side span section 2 and the middle span section, and prestress is applied to them respectively.

[0052] After fixing the support section 1 to the pier with a temporary device, the second stiffening plate 14 of the side span section 2 is overlapped with the first stiffening plate 5 of the support section 1; then the fasteners 18 are passed through the support section 1, the first stiffening plate 5 and the second stiffening plate 14 to fix the support section 1 and the side span section 2; the reserved top plate 9 is hoisted into the installation space 8.

[0053] The third stiffening plate of the mid-span section is connected to the first stiffening plate 5 of the support section 1, and the mid-span section and the support section 1 are fixed by fasteners 18 passing through the mid-span section, the first stiffening plate 5 and the third stiffening plate; the reserved top plate 9 is hoisted into the installation space 8.

[0054] Once the composite beam reaches the required strength, the temporary installations will be removed, and construction will be completed.

[0055] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A precast steel-concrete composite beam, characterized in that, include: The support section (1) is located on the pier and includes a first precast steel beam (3) and a first precast concrete panel (4) that are connected to each other. A first stiffening plate (5) is provided on the first bottom plate of the first precast steel beam (3) near the end. The side span (2) includes a second precast steel beam (12) and a second precast concrete panel (13) connected to each other. The second bottom plate of the second precast steel beam (12) is provided with a second stiffening plate (14) at the end near the support section (1). The second stiffening plate (14) extends to the outside of the second bottom plate to overlap with the first stiffening plate (5). Fasteners (18) are provided through the support section (1), the first stiffening plate (5) and the second stiffening plate (14) to fix the support section (1) and the side span section (2); The first stiffening plate (5) consists of multiple vertical plates spaced apart, and the second stiffening plate (14) consists of U-shaped stiffening ribs. The width of the U-shaped stiffening ribs is smaller than the distance between two adjacent vertical plates, so that the second stiffening plate (14) overlaps between two adjacent first stiffening plates (5).

2. The precast steel-concrete composite beam according to claim 1, characterized in that, It also includes a mid-span section, which includes a third precast steel beam and a third precast concrete panel that are connected to each other. The third bottom plate of the third precast steel beam is provided with a third stiffening plate near its end. The third stiffening plate extends to the outside of the third bottom plate to overlap with the first stiffening plate (5).

3. The precast steel-concrete composite beam according to claim 2, characterized in that, The third stiffening plate is a U-shaped stiffening rib, and the width of the U-shaped stiffening rib is less than the distance between two adjacent vertical plates, so that the third stiffening plate overlaps between two adjacent first stiffening plates (5).

4. The precast steel-concrete composite beam according to claim 2 or 3, characterized in that, The first web plate (6) of the support section (1) is provided with a first reinforcing plate (10), which extends horizontally outward and is provided with a first connecting member (11); the second web plate (15) of the side span section (2) is provided with a second reinforcing plate (16), which extends horizontally inward and is provided with a second connecting member (17); the third web plate of the middle span section is provided with a third reinforcing plate, which extends horizontally inward and is provided with a third connecting member.

5. A construction method for a precast steel-concrete composite beam as described in any one of claims 1-4, characterized in that, Includes the following steps: The first precast steel beam (3) and the first precast concrete panel (4), the second precast steel beam (12) and the second precast concrete panel (13) are assembled respectively to form the support section (1) and the side span section (2). After the support section (1) is fixed to the pier, the second stiffening plate (14) of the side span section (2) is overlapped with the first stiffening plate (5) of the support section (1); Then fasteners (18) are passed through the support section (1), the first stiffening plate (5) and the second stiffening plate (14) to fix the support section (1) and the side span section (2).

6. The construction method of the precast steel-concrete composite beam according to claim 5, characterized in that, Installation space (8) is reserved at the ends of the first precast steel beam (3) with the first stiffening plate (5) and the second precast steel beam (12) with the second stiffening plate (14). After the support section (1) and the side span section (2) are fixed by fasteners (18), the reserved top plate (9) is installed in the installation space (8).

7. The construction method of the precast steel-concrete composite beam according to claim 6, characterized in that, The installation space (8) is 1 meter long along the length of the composite beam.

8. The construction method of the precast steel-concrete composite beam according to any one of claims 5-7, characterized in that, Mounting holes (7) for fasteners (18) are reserved on the support section (1), the first stiffening plate (5) and the second stiffening plate (14).

9. The construction method of the precast steel-concrete composite beam according to claim 6, characterized in that, It also includes connecting the third stiffening plate of the middle span section to the first stiffening plate (5) of the support section (1) after assembling the reserved top plate (9), and fixing it with fasteners (18).

10. The construction method of the precast steel-concrete composite beam according to claim 9, characterized in that, It also includes the step of assembling a reserved top plate (9) into the installation space (8) between the third precast steel beam and the first precast steel beam (3).

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