High crack resistance composite beam and bridge and construction method

Abstract

The application discloses a high-anti-cracking combined beam, a bridge and a construction method, and relates to the technical field of combined beam bridge structures. The combined beam comprises a negative bending moment combined beam section, which comprises a negative bending moment zone lower steel beam arranged on a middle support support, a negative bending moment zone upper steel beam arranged on the negative bending moment zone lower steel beam, and a negative bending moment zone bridge deck arranged on the negative bending moment zone upper steel beam. Before the negative bending moment zone lower steel beam and the negative bending moment zone upper steel beam are connected, the negative bending moment zone bridge deck is connected with the negative bending moment zone upper steel beam and prestress is tensioned. The prestress is only applied to the negative bending moment zone upper steel beam and the negative bending moment zone bridge deck, and the negative bending moment zone lower steel beam does not need to bear the pressure transmitted by the prestress. The application solves the problems of the prior art, such as the consumption of part of the prestress by the lower steel structure, the low efficiency of the prestress and the waste of steel materials when the prestress is arranged in the concrete bridge deck to prevent cracking.

Description

Technical Field

[0001] This invention relates to the field of composite beam bridge structure technology, specifically to a composite beam and bridge with high crack resistance and a construction method. Background Technology

[0002] Composite beam bridges refer to bridges with beam spans as their basic structural element, combining multiple structural elements. When two or more systems are overlapped, the overall structural reaction characteristics remain similar to those of a beam subjected to bending loads. Commonly used composite beams have a steel structure at the bottom and a concrete deck at the top. In this structure, during the positive bending moment zone at mid-span, the lower steel structure is under tension while the upper concrete deck is under compression, resulting in a reasonable stress distribution. However, in the negative bending moment zone at the mid-support, the lower steel structure is under compression while the upper concrete deck is under tension, making the deck prone to cracking. Therefore, the crack-resistant design of the concrete deck in the negative bending moment zone of a composite beam is a key challenge.

[0003] In existing technologies, when prestressing is applied to the concrete bridge deck to prevent cracking, some of the prestress is consumed by the underlying steel structure, resulting in low prestressing efficiency and waste of steel. Summary of the Invention

[0004] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a composite beam and bridge with high crack resistance and a construction method, which can solve the problem that when the existing technology uses prestressing in the concrete bridge deck to prevent cracking, some of the prestress is consumed by the lower steel structure, resulting in low prestressing efficiency and waste of steel.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] Firstly, this solution provides a composite beam with high crack resistance, including a negative bending moment composite beam segment, wherein the negative bending moment composite beam segment includes:

[0007] The steel beam in the negative bending moment zone is used to be erected on the support at the intermediate support point;

[0008] The upper steel beam in the negative bending moment zone is installed on the lower steel beam in the negative bending moment zone.

[0009] The bridge deck in the negative bending moment zone is installed on the upper steel beam in the negative bending moment zone. Before the lower steel beam in the negative bending moment zone is connected to the upper steel beam in the negative bending moment zone, the bridge deck in the negative bending moment zone is connected to the upper steel beam in the negative bending moment zone and prestressed.

[0010] In some alternative solutions, the negative bending moment zone bridge deck includes multiple precast negative bending moment zone bridge decks spaced apart along the longitudinal direction of the bridge, and the wet joints between the precast negative bending moment zone bridge decks are connected by cast-in-place negative bending moment zone bridge decks.

[0011] In some alternative solutions, the upper steel beam in the negative bending moment zone includes the same number of upper steel beam segments as the precast bridge deck in the negative bending moment zone. The upper steel beam segments are connected sequentially along the longitudinal direction of the bridge and connected to the corresponding precast bridge deck in the negative bending moment zone.

[0012] In some alternative designs, the upper steel beam segment is an I-beam, and the upper steel beam segment is bolted to the adjacent upper steel beam segment via a connecting plate bolted at the web connection.

[0013] In some alternative designs, the lower steel beam in the negative bending moment zone is an I-beam, and the lower flange of the upper steel beam segment is bolted to the upper flange of the lower steel beam in the negative bending moment zone.

[0014] In some alternatives, the bridge deck in the negative moment zone is prestressed by tensioning prestressed steel bars arranged in the bridge deck in the negative moment zone along the longitudinal direction of the bridge.

[0015] Secondly, this solution also provides a bridge with high crack resistance, comprising a negative bending moment composite beam segment and positive bending moment composite beam segments located at both ends thereof, wherein the negative bending moment composite beam segment includes:

[0016] The steel beam in the negative bending moment zone is used to be erected on the support at the intermediate support point;

[0017] The upper steel beam in the negative bending moment zone is installed on the lower steel beam in the negative bending moment zone.

[0018] The bridge deck in the negative bending moment zone is installed on the upper steel beam in the negative bending moment zone. Before the lower steel beam in the negative bending moment zone is connected to the upper steel beam in the negative bending moment zone, the bridge deck in the negative bending moment zone is connected to the upper steel beam in the negative bending moment zone and prestressed.

[0019] In some alternative schemes, the positive bending moment composite beam segment includes a positive bending moment zone bridge deck that is flush with the negative bending moment zone bridge deck, and a positive bending moment zone steel beam is provided below the positive bending moment zone bridge deck, the positive bending moment zone steel beam being flush with the upper steel beam of the negative bending moment zone.

[0020] Thirdly, this solution also provides a construction method for high crack-resistant composite beams, which is used to erect the high crack-resistant composite beams described in any of the above-mentioned embodiments, including:

[0021] Hoist the lower steel beam in the negative bending moment zone to the middle support;

[0022] The bridge deck and upper steel beam in the negative bending moment zone are set on the lower steel beam in the negative bending moment zone, and the bridge deck in the negative bending moment zone is tensioned with prestress.

[0023] Connect the upper steel beam in the negative bending moment zone to the lower steel beam in the negative bending moment zone.

[0024] In some alternative solutions, the arrangement of the bridge deck and the upper steel beam in the negative bending moment zone on the lower steel beam in the negative bending moment zone includes:

[0025] Multiple precast bridge decks in negative bending moment zones are connected to the corresponding upper steel beam segments by shear studs to form small composite beams;

[0026] Each small composite beam is hoisted to the top of the lower steel beam in the negative bending moment zone. The wet joints between the precast bridge decks in the negative bending moment zone are poured to form the bridge deck in the negative bending moment zone. After that, the bridge deck in the negative bending moment zone is tensioned with prestress.

[0027] Compared with existing technologies, the advantages of this invention are as follows: This solution divides the steel beam in the negative bending moment composite beam segment into two parts: an upper steel beam in the negative bending moment zone and a lower steel beam in the negative bending moment zone. Before connecting the upper and lower steel beams in the negative bending moment zone, the bridge deck in the negative bending moment zone is connected to the upper steel beam and prestressed. The prestress is applied only to the upper steel beam and the bridge deck in the negative bending moment zone, and the lower steel beam does not need to bear the pressure transmitted by the prestress. This solves the problem in existing technologies where prestressing is applied within the concrete bridge deck to prevent cracking, resulting in some prestress being consumed by the lower steel structure, low prestressing efficiency, and waste of steel. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of the high crack resistance composite beam in an embodiment of the present invention;

[0030] Figure 2 This is a schematic diagram of the cross-sectional structure of a negative bending moment composite beam segment in an embodiment of the present invention;

[0031] Figure 3 This is a schematic diagram of the cross-sectional structure of a positive bending moment composite beam segment in an embodiment of the present invention;

[0032] Figure 4 This is a schematic diagram of the cross-sectional structure of the small composite beam in an embodiment of the present invention;

[0033] Figure 5 This is a schematic diagram of the elevation structure of the small composite beam in an embodiment of the present invention;

[0034] Figure 6 This is a schematic flowchart of the construction method for high crack-resistant composite beams in an embodiment of the present invention;

[0035] In the diagram: 1. Bridge deck in the negative bending moment zone; 2. Upper steel beam in the negative bending moment zone; 3. Lower steel beam in the negative bending moment zone; 4. Precast bridge deck in the negative bending moment zone; 5. Cast-in-place bridge deck in the negative bending moment zone; 6. Upper steel beam segment; 7. Connecting plate; 8. Bridge deck in the positive bending moment zone; 9. Mid-point support; 10. Steel beam in the positive bending moment zone; 11. Prestressed steel reinforcement. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0037] The embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0038] like Figure 1 , Figure 2 and Figure 3 As shown, in a first aspect, the present invention provides a composite beam with high crack resistance, comprising a negative bending moment composite beam segment, the negative bending moment composite beam segment comprising:

[0039] The steel beam 3 in the negative bending moment zone is used to be erected on the support 9 at the middle support point;

[0040] The upper steel beam 2 in the negative bending moment zone is set on the lower steel beam 3 in the negative bending moment zone.

[0041] The bridge deck 1 in the negative bending moment zone is set on the upper steel beam 2 in the negative bending moment zone. Before the lower steel beam 3 in the negative bending moment zone is connected to the upper steel beam 2 in the negative bending moment zone, the bridge deck 1 in the negative bending moment zone is connected to the upper steel beam 2 in the negative bending moment zone and prestressed.

[0042] In this embodiment, the steel beam in the negative bending moment composite beam segment is divided into upper steel beam 2 and lower steel beam 3 in the negative bending moment zone. Before the upper steel beam 2 and lower steel beam 3 are connected, the bridge deck 1 in the negative bending moment zone is connected to the upper steel beam 2 and prestressed. The prestress is applied only to the upper steel beam 2 and the bridge deck 1 in the negative bending moment zone; the lower steel beam 3 does not need to bear the pressure transmitted by the prestress. This solves the problem in the prior art where prestressing is applied within the concrete bridge deck to prevent cracking, resulting in some prestress being consumed by the lower steel structure, low prestressing efficiency, and waste of steel.

[0043] In some optional embodiments, the negative bending moment zone bridge deck 1 includes a plurality of precast negative bending moment zone bridge decks 4 spaced apart along the longitudinal direction of the bridge, and the wet joints between the precast negative bending moment zone bridge decks 4 are connected by cast-in-place negative bending moment zone bridge decks 5.

[0044] like Figure 4 and Figure 5 As shown, in some optional embodiments, the upper steel beam 2 in the negative bending moment zone includes the same number of upper steel beam segments 6 as the precast bridge deck 4 in the negative bending moment zone. The upper steel beam segments 6 are connected sequentially along the longitudinal direction of the bridge and connected to the corresponding precast bridge deck 4 in the negative bending moment zone.

[0045] In this embodiment, the upper steel beam segment 6 is connected to the precast bridge deck 4 in the negative bending moment zone by shear studs to form a small composite beam. After the upper steel beam segments 6 are connected sequentially along the longitudinal direction of the bridge, they form the upper steel beam 2 in the negative bending moment zone, the length of which is equal to that of the lower steel beam 3 in the negative bending moment zone.

[0046] In some optional embodiments, the upper steel beam segment 6 is an I-shaped steel beam, and the upper steel beam segment 6 is bolted to the adjacent upper steel beam segment 6 by a connecting plate 7 provided at the web connection.

[0047] In this embodiment, the upper steel beam segment 6 is connected to the upper flange plate of the adjacent upper steel beam segment 6 by welding.

[0048] In some optional embodiments, the lower steel beam 3 in the negative bending moment zone is an I-beam, and the lower flange of the upper steel beam segment 6 is bolted to the upper flange of the lower steel beam 3 in the negative bending moment zone.

[0049] In some alternative embodiments, the bridge deck 1 in the negative bending moment zone is prestressed by prestressed steel bars 11 arranged in the bridge deck 1 in the negative bending moment zone along the longitudinal direction of the bridge.

[0050] In this embodiment, multiple prestressed steel bars 11 are spaced apart along the transverse direction within the bridge deck 1 in the negative bending moment zone.

[0051] Secondly, the present invention also provides a bridge with high crack resistance, comprising a negative bending moment composite beam segment and positive bending moment composite beam segments located at both ends thereof, wherein the negative bending moment composite beam segment includes:

[0052] The steel beam 3 in the negative bending moment zone is used to be erected on the support 9 at the middle support point;

[0053] The upper steel beam 2 in the negative bending moment zone is set on the lower steel beam 3 in the negative bending moment zone.

[0054] The bridge deck 1 in the negative bending moment zone is set on the upper steel beam 2 in the negative bending moment zone. Before the lower steel beam 3 in the negative bending moment zone is connected to the upper steel beam 2 in the negative bending moment zone, the bridge deck 1 in the negative bending moment zone is connected to the upper steel beam 2 in the negative bending moment zone and prestressed.

[0055] In some optional embodiments, the positive bending moment composite beam segment includes a positive bending moment zone bridge deck 8 that is flush with the negative bending moment zone bridge deck 1, and a positive bending moment zone steel beam 10 is provided below the positive bending moment zone bridge deck 8, which is flush with the upper steel beam 2 of the negative bending moment zone.

[0056] In this embodiment, the steel beam 10 in the positive bending moment zone is connected to the bridge deck 8 in the positive bending moment zone by shear studs. The height of the upper steel beam 2 and the lower steel beam 3 in the negative bending moment zone after connection is equal to the height of the steel beam 10 in the positive bending moment zone. The height of the upper steel beam 2 in the negative bending moment zone is minimized as much as possible while meeting construction requirements, so that more prestress is applied to the bridge deck 1 in the negative bending moment zone, thereby improving the efficiency of prestress application.

[0057] like Figure 6 As shown, in a third aspect, the present invention also provides a construction method for a high crack-resistant composite beam, which is used to erect the high crack-resistant composite beam described in any of the above claims, comprising:

[0058] S1: Lift the lower steel beam 3 in the negative bending moment zone to the middle support 9.

[0059] S2: The bridge deck 1 in the negative bending moment zone and the upper steel beam 2 in the negative bending moment zone are placed on the lower steel beam 3 in the negative bending moment zone, and the bridge deck 1 in the negative bending moment zone is tensioned with prestress.

[0060] S3: Connect the upper steel beam 2 in the negative bending moment zone to the lower steel beam 3 in the negative bending moment zone.

[0061] In some alternative embodiments, before hoisting the lower steel beam 3 in the negative bending moment zone to the central support 9, the steel beam 10 in the positive bending moment zone and the lower steel beam 3 in the negative bending moment zone are erected and connected.

[0062] In some optional embodiments, the bridge deck 1 in the negative bending moment zone and the upper steel beam 2 in the negative bending moment zone are mounted on the lower steel beam 3 in the negative bending moment zone, including:

[0063] Multiple precast bridge deck panels 4 in negative bending moment zones are connected to the corresponding upper steel beam segments 6 by shear studs to form small composite beams;

[0064] Each small composite beam is hoisted to the top of the lower steel beam 3 in the negative bending moment zone. The wet joint between the precast bridge deck 4 in the negative bending moment zone is poured to form the bridge deck 1 in the negative bending moment zone. Then, the bridge deck 1 in the negative bending moment zone is tensioned with prestress.

[0065] In some alternative embodiments, the steel beam 10 in the positive bending moment region and the steel beam 2 in the negative bending moment region are connected before the upper steel beam 2 in the negative bending moment region is connected to the lower steel beam 3 in the negative bending moment region.

[0066] In some alternative embodiments, after connecting the upper steel beam 2 in the negative bending moment zone to the lower steel beam 3 in the negative bending moment zone, a wet joint is poured between the bridge deck 8 in the positive bending moment zone and the bridge deck 1 in the negative bending moment zone. The composite beams form an integral structure.

[0067] In summary, this invention divides the steel beams in the negative bending moment composite beam segment into two parts: an upper steel beam 2 in the negative bending moment zone and a lower steel beam 3 in the negative bending moment zone. Before the upper steel beam 2 and the lower steel beam 3 in the negative bending moment zone are connected, the bridge deck 1 in the negative bending moment zone is connected to the upper steel beam 2 and prestressed. The prestress is only applied to the upper steel beam 2 and the bridge deck 1 in the negative bending moment zone; the lower steel beam 3 in the negative bending moment zone does not need to bear the pressure transmitted by the prestress. This solves the problem in the prior art where prestressing is applied within the concrete bridge deck to prevent cracking, resulting in some prestress being consumed by the lower steel structure, low prestressing efficiency, and waste of steel.

[0068] When prestressing is applied within the bridge deck 1 in the negative bending moment zone, the prestress is only applied to the upper steel beam 2 and the bridge deck 1 in the negative bending moment zone. Since the upper steel beam 2 has a small area, the majority of the prestress is applied within the concrete bridge deck 1 in the negative bending moment zone, resulting in high efficiency. Even with relatively low prestress, the bridge deck 1 in the negative bending moment zone can store a high level of compressive stress. Because the prestress is efficiently applied only to the upper steel beam 2 and the bridge deck 1 in the negative bending moment zone, the lower steel beam 3 in the negative bending moment zone does not need to bear the pressure transmitted by the prestress, thus reducing the amount of lower steel beam 3 required.

[0069] In the description of this application, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0070] It should be noted that in this application, relational terms such as "first" and "second" are used merely 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 a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0071] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A bridge with high crack resistance, characterized in that, It includes a composite beam segment with negative bending moment and composite beam segments with positive bending moment located at both ends thereof, wherein the composite beam segment with negative bending moment includes: The lower steel beam (3) in the negative bending moment zone is used to be erected on the middle support (9); The upper steel beam (2) in the negative bending moment zone is set on the lower steel beam (3) in the negative bending moment zone. The bridge deck (1) in the negative bending moment zone is set on the upper steel beam (2) in the negative bending moment zone. Before the lower steel beam (3) in the negative bending moment zone is connected to the upper steel beam (2) in the negative bending moment zone, the bridge deck (1) in the negative bending moment zone is connected to the upper steel beam (2) in the negative bending moment zone and prestressed. The negative moment zone bridge deck (1) includes multiple negative moment zone precast bridge decks (4) spaced apart along the longitudinal direction of the bridge, and the wet joints between each negative moment zone precast bridge deck (4) are connected by negative moment zone cast-in-place bridge decks (5). The upper steel beam (2) in the negative bending moment zone includes the same number of upper steel beam segments (6) as the precast bridge deck (4) in the negative bending moment zone. The upper steel beam segments (6) are connected sequentially along the longitudinal direction of the bridge and connected to the corresponding precast bridge deck (4) in the negative bending moment zone. The lower steel beam (3) in the negative bending moment zone is an I-beam, and the lower flange of the upper steel beam segment (6) is connected to the upper flange of the lower steel beam (3) in the negative bending moment zone by bolts. The upper steel beam segment (6) is connected to the lower part of the precast bridge deck (4) in the negative bending moment zone by shear studs to form a small composite beam. The small composite beam is hoisted to the upper part of the lower steel beam (3) in the negative bending moment zone. The wet joint between the precast bridge deck (4) in the negative bending moment zone is poured to form the bridge deck (1) in the negative bending moment zone. Then, the bridge deck (1) in the negative bending moment zone is tensioned with prestress. The positive bending moment composite beam segment includes a positive bending moment zone bridge deck (8) that is flush with the negative bending moment zone bridge deck (1). A positive bending moment zone steel beam (10) is provided below the positive bending moment zone bridge deck (8). The positive bending moment zone steel beam (10) is flush with the upper steel beam (2) of the negative bending moment zone.

2. The high crack resistance bridge as described in claim 1, characterized in that, The upper steel beam segment (6) is an I-shaped steel beam, and the upper steel beam segment (6) is bolted to the adjacent upper steel beam segment (6) by a connecting plate (7) set at the web connection.

3. The high crack resistance bridge as described in claim 1, characterized in that, The negative bending moment zone bridge deck (1) is prestressed by prestressed steel bars (11) set in the negative bending moment zone bridge deck (1) along the longitudinal direction of the bridge.

4. A construction method for a composite beam with high crack resistance, characterized in that, It is used for erecting high crack-resistant bridges as described in any one of claims 1-3, comprising: Hoist the lower steel beam (3) in the negative bending moment zone to the middle support (9); The bridge deck (1) in the negative bending moment zone and the upper steel beam (2) in the negative bending moment zone are set on the lower steel beam (3) in the negative bending moment zone, and the bridge deck (1) in the negative bending moment zone is tensioned with prestress. Connect the upper steel beam (2) in the negative bending moment zone to the lower steel beam (3) in the negative bending moment zone.

5. The construction method for high crack resistance composite beams as described in claim 4, characterized in that, The method of setting the bridge deck (1) in the negative bending moment zone and the upper steel beam (2) in the negative bending moment zone on the lower steel beam (3) in the negative bending moment zone includes: Multiple precast bridge deck panels (4) in negative bending moment zones are connected to the corresponding upper steel beam segments (6) by shear studs to form small composite beams; Hoist each small composite beam to the top of the lower steel beam (3) in the negative bending moment zone, pour the wet joint between the precast bridge deck (4) in the negative bending moment zone, and after forming the bridge deck (1) in the negative bending moment zone, tension the prestress on the bridge deck (1) in the negative bending moment zone.

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