Flying swallow type arch bridge arched girder combination area structure and design method thereof

Abstract

The invention relates to the field of bridge construction, in particular to a flying swallow type arch bridge arched beam combination area structure and a design method thereof.The flying swallow type arch bridge arched beam combination area structure comprises a main beam connecting section, a side arch rib is connected to the lower portion of the main beam connecting section, a groove is formed in the face, facing the main beam connecting section, of the side arch rib, and the side arch rib is connected with the main beam connecting section through the groove; the surfaces, facing the grooves, of the main beam connecting sections are all provided with shearing force connecting pieces, the main beam connecting sections are steel structural pieces, the side arch ribs are of concrete structures, the side arch ribs are arranged to be of the concrete structures, the concrete side arch ribs do not need to be designed into the steel structures and do not need to be ballasted within the range of the arched beam combination area, and the construction efficiency is improved; and the side arch ribs and the main beam connecting sections are connected through the shearing force connecting pieces, so that the force transmission path of the whole arched beam combining area is clearer, the force transmission reliability is improved, and the situation that the arch bridge structure is unstable in stress is reduced.

Description

Technical Field

[0001] This invention relates to the field of bridge engineering, and in particular to a structure and design method for the arch-beam joint zone of a swallow-shaped arch bridge. Background Technology

[0002] In areas with low foundation bearing capacity, the construction of long-span arch bridges mainly adopts the swallow arch bridge system, which includes two forms: thrustless arch bridges and partially thrust arch bridges.

[0003] Currently, in the flying swallow arch bridge system, the arch-beam joint area composed of steel main beam and concrete side arch generally adopts a pressure-bearing scheme. In this scheme, the arch ribs at a certain range at the end of the side arch are designed as steel structures, forming an integral structure with the steel main beam. The force transmission between the main beam and the side arch is mainly achieved through the pressure bearing of the steel-concrete joint surface of the side arch.

[0004] The disadvantages of using a pressure-bearing scheme in the arch-beam joint area are: (1) A certain number of anchor bolts are arranged on the steel-concrete joint surface in the pressure-bearing scheme to bear the axial force, bending moment and shear force transmitted between the main beam and the side arch. Under the high-frequency vibration of the bridge deck live load, especially the high-speed train load, if the anchor bolts on the joint surface loosen later, the load transmission efficiency will be reduced, thereby threatening the structural safety. According to extensive research, the probability of anchor bolts loosening under high-frequency train vibration is generally 5% to 10%; (2) The side and middle spans of the flying swallow arch bridge are generally small. The pressure-bearing scheme requires the arch ribs at the end of the side arch to be designed as steel structures. In order to ensure that the support has a certain pressure reserve, a large amount of ballast needs to be carried out in the arch-beam joint area. The stiffening ribs of the joint area partition are densely distributed, and the ballast construction is more complicated. During the ballast concrete construction, the steel structure in the joint area is at risk of local instability; (3) The arch ribs at the end of the side arch in the pressure-bearing scheme need to be steel structures, and a large amount of ballast needs to be carried out later, which will greatly increase the cost of the project. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of existing technologies, such as the use of steel or steel-concrete structures for the side arches in traditional swallow-shaped arch bridges, which requires a certain number of anchor bolts to bear the axial force, bending moment and shear force transmitted between the main beam and the side arch. However, the anchor bolts are prone to loosening during use, which reduces the load transfer efficiency and reduces the stress stability of the arch bridge structure. This invention provides a structure and design method for the arch-beam joint zone of a swallow-shaped arch bridge.

[0006] In a first aspect, the present invention provides a structure for the arch-beam joint area of ​​a swallow-shaped arch bridge, including a main beam connecting section, wherein a side arch rib is connected below the main beam connecting section. The side arch rib has a groove on the side facing the main beam connecting section, and the side arch rib is connected to the main beam connecting section through the groove; The main beam connecting section is provided with shear connectors on the surface facing the groove; The main beam connecting section is a steel structure, and the side arch rib is a concrete structure.

[0007] This invention provides a structural design for the arch-beam junction of a swallow-shaped arch bridge. By connecting the main beam connection section and the side arch ribs into a single unit using shear connectors, the arch-beam junction forms a stable, integrated stress system. This effectively disperses and transfers the shear force between the main beam and the side arch ribs, improving the overall stiffness and torsional resistance of the structure. Simultaneously, the side arch ribs are reliably connected to the main arch via arch seats, allowing the pressure from the main arch to be smoothly transferred to the side arch ribs and the main beam connection section, reducing stress concentration and improving the fatigue life and durability of the arch-beam junction. Furthermore, this structure reduces the problems of localized deformation and stress reduction caused by traditional welding or anchor bolt connections. In this application, shear connectors are used to connect the main beam connection section of the steel structure to the side arch ribs of the concrete structure, enabling the side arch... After being subjected to force, the ribs transmit the force to the main beam connection section through shear connectors. Shear connectors connect the side arch ribs to the main beam connection section, creating a large-area, multi-point force transmission zone between the side arch ribs and the main beam connection section. However, the arch-beam joint area is often subjected to high-frequency live load vibration during use. When the structure is under high-frequency live load vibration, anchor bolt connections are prone to localized stress concentration around the bolt hole walls, leading to micro-crack propagation and fatigue accumulation. This results in bolt loosening, hole wall erosion, or slippage, ultimately causing a decrease in the stiffness of the arch-beam joint area or even connection failure. This application addresses this issue by arranging shear connectors between the main beam connection section and the side arch ribs, creating a multi-point, large-area connection. When high-frequency live load vibration acts on the structure, the shear connectors can disperse and transmit vibration energy to a wider range of concrete and steel components, avoiding excessive stress at a single point, thereby improving load transmission efficiency and enhancing the stress stability of the arch bridge structure.

[0008] Preferably, the main beam connecting section is a hollow structure, and stiffening ribs are provided on each surface inside the main beam connecting section.

[0009] The main beam connection section is a hollow structure with stiffening ribs on each of its internal surfaces. This not only effectively reduces the self-weight of the main beam connection section, thereby reducing material usage and construction costs, but also improves the overall stiffness and stability of the main beam connection section, enhancing its bending, shear, and torsional resistance, thus ensuring the safety and reliability of the arch-beam joint area under stress.

[0010] Preferably, the shear connector includes a transverse shear member located on the sidewall of the groove; The shear connector further includes a longitudinal shear member located on the bottom surface of the groove.

[0011] By setting transverse shear members on the sidewalls of the groove and longitudinal shear members on the bottom surface of the groove, a reliable mechanical connection is formed between the main beam connection section and the side arch rib in both the transverse and longitudinal directions. This effectively disperses and transmits shear forces in different directions, improves the overall stress stability and shear resistance of the arch-beam joint area, and reduces the problem of local stress concentration caused by a single-direction connection.

[0012] Preferably, the stiffening ribs include transverse stiffening ribs, which are symmetrically arranged and located on the inner sidewall of the main beam connection section; The stiffening ribs also include longitudinal stiffening ribs, which are symmetrically arranged and located on the top and bottom surfaces inside the main beam connection section.

[0013] The stiffening ribs include symmetrically arranged transverse stiffening ribs and longitudinal stiffening ribs, which are respectively set on the inner sidewalls, top surface and bottom surface of the main beam connection section. They can not only uniformly enhance the stiffness and stability of the main beam connection section in different directions, but also effectively improve its bending, shear and torsional resistance, avoid local structural deformation, and thus ensure the safety and durability of the arch-beam joint area under complex loads.

[0014] Preferably, the shear connector is connected to the main beam connection section by welding.

[0015] In a second aspect, the present invention provides a swallow-shaped arch bridge structure, including the above-mentioned swallow-shaped arch bridge arch-beam joint area structure, and also including a main arch. The arch-beam joint area structure includes two structures, and each of the arch-beam joint area structures is connected to the main arch through an arch seat. The main arch is connected to a main beam below it.

[0016] This invention provides a swallow-shaped arch bridge structure that connects the main arch to the arch-beam joint area. By optimizing the force transmission in the arch-beam joint area, the structural stability of the entire swallow-shaped arch bridge is improved. Specifically, under the action of its own weight and the load on the bridge deck, the main arch is compressed and tends to push outward, transmitting the force to the side arch ribs. After being compressed, the side arch ribs transmit the force to the main beam connection section through shear connectors. The main beam connection section is under tension, thereby constraining the outward pushing tendency of the main arch and thus offsetting part of the thrust of the main arch.

[0017] Preferably, the main beam includes the main beam connecting section and the main beam splicing section connected to the main beam connecting section, and the top of the main beam splicing section is connected to the main arch by a sling.

[0018] Preferably, the bottom of the main beam is connected to the side arch rib and the arch seat by a column.

[0019] Preferably, the arch base is fixedly connected to the main arch and the side arch ribs.

[0020] In a third aspect, the present invention provides a design method for the arch-beam joint area structure of a swallow-shaped arch bridge, used to design the aforementioned arch-beam joint area structure of a swallow-shaped arch bridge, comprising the following steps: A finite element model of the arch bridge is established, and the axial force of the main beam connection segment is obtained based on the finite element model of the arch bridge. The cross-sectional heights of several of the aforementioned side arch ribs are preset; Based on the finite element model of the arch bridge, the cross-sectional height of each side arch rib is simulated to obtain the relationship between the length of the shear connection arrangement range and the cross-sectional height of the side arch rib. The finite element model of the arch bridge is divided into segments to obtain the number of shear connectors in each segment; Simulation analysis was performed on the finite element model of the arch bridge to obtain the shear force distribution information of the shear connection member per unit length; Based on the number of shear connectors in each segment, the spacing between the shear connectors in each segment is obtained.

[0021] This invention provides a design method for the arch-beam joint zone of a swallow-shaped arch bridge. This method allows for the precise acquisition of axial and shear force distributions in the main beam connection section during the design phase, combined with finite element analysis. Based on simulation results of different cross-sectional heights of the side arch ribs, a correspondence between the arrangement range of shear connectors and their cross-sectional heights is established, enabling scientific optimization of the length, quantity, and spacing of the shear connectors. This method avoids the structural redundancy or insufficient strength problems caused by traditional parameter selection based on experience. It effectively reduces material usage and structural weight while meeting strength and stability requirements in the arch-beam joint zone, and improves construction operability and economy.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention provides a structure for the arch-beam joint zone of a swallow-shaped arch bridge. By connecting the main beam connecting section and the side arch ribs into a single unit using shear connectors, the arch-beam joint zone forms a stable overall stress system. This effectively disperses and transmits the shear force between the main beam and the side arch ribs, improving the overall stiffness and torsional resistance of the structure. Simultaneously, the side arch ribs are reliably connected to the main arch via arch seats, allowing the pressure of the main arch to be smoothly transmitted to the side arch ribs and the main beam connecting section, reducing stress concentration and improving the fatigue life and durability of the arch-beam joint zone. Furthermore, this structure reduces the problems of localized deformation and stress reduction caused by traditional welding or anchor bolt connections. In this application, shear connectors are used to connect the main beam connecting section of the steel structure to the side arch ribs of the concrete structure, enabling the side arch ribs to form a stable overall stress system. This effectively disperses and transmits the shear force between the main beam and the side arch ribs, improving the overall stiffness and torsional resistance of the structure. After being subjected to force, the arch ribs transfer the force to the main beam connection section through shear connectors. Shear connectors connect the side arch ribs to the main beam connection section, creating a large-area, multi-point force transmission zone between the side arch ribs and the main beam connection section. However, the arch-beam joint area is often subjected to high-frequency live load vibration during use. When the structure is under high-frequency live load vibration, anchor bolt connections are prone to localized stress concentration around the bolt hole walls, leading to micro-crack propagation and fatigue accumulation. This results in bolt loosening, hole wall erosion, or slippage, ultimately causing a decrease in the stiffness of the arch-beam joint area or even connection failure. This application addresses this issue by arranging shear connectors between the main beam connection section and the side arch ribs, creating a multi-point, large-area connection. When high-frequency live load vibration acts on the structure, the shear connectors can disperse and transfer the vibration energy to a wider range of concrete and steel components, avoiding excessive stress at a single point, thereby improving load transfer efficiency and enhancing the stress stability of the arch bridge structure.

[0023] 2. This invention provides a swallow-shaped arch bridge structure, which connects the main arch of the swallow-shaped arch bridge structure with the arch-beam joint area. By optimizing the force transmission in the arch-beam joint area, the structural stability of the entire swallow-shaped arch bridge is improved. Specifically, under the action of its own weight and the load on the arch bridge deck, the main arch is compressed and tends to push outward, transmitting the force to the side arch ribs. After being compressed, the side arch ribs transmit the force to the main beam connection section through shear connectors. The main beam connection section is under tension, thereby constraining the outward pushing trend of the main arch and thus offsetting part of the thrust of the main arch.

[0024] 3. This invention provides a design method for the arch-beam joint zone of a swallow-shaped arch bridge. This method allows for the precise acquisition of axial and shear force distributions in the main beam connection section during the design phase, combined with finite element analysis. Based on simulation results of different cross-sectional heights of the side arch ribs, a correspondence between the shear connector arrangement range and cross-sectional height is established, enabling scientific optimization of the shear connector arrangement length, quantity, and spacing. This method avoids the structural redundancy or insufficient strength problems caused by traditional parameter selection based on experience. It effectively reduces material usage and structural weight while meeting strength and stability requirements in the arch-beam joint zone, and improves construction operability and economy. Attached Figure Description

[0025] Figure 1 This is a plan view of the swallow-shaped arch bridge in this invention; Figure 2 This is a structural diagram of the swallow-shaped arch bridge in this invention; Figure 3 This is a structural diagram of the arch-beam joint area of ​​the swallow-shaped arch bridge in this invention; Figure 4 This is a schematic diagram of the connection between the main beam connecting section and the side arch rib in this invention; Figure 5 This is a cross-sectional view of the side rib arch in this invention; Figure 6 This is a cross-sectional view of the main beam connection section in this invention; Figure 7 This is a finite element model diagram of the arch-beam joint zone structure of the swallow-shaped arch bridge in this invention; Figure 8 This is a schematic diagram showing the variation of the force transmission path length in the arch-beam joint area with the height of the side arch section in this invention; Figure 9 This is a schematic diagram of the shear force distribution of the shear connection component in the arch-beam joint zone of the present invention; Figure 10 This is a flowchart of the design method for the arch-beam joint zone structure of the swallow-shaped arch bridge in this invention.

[0026] Markings in the diagram: 1-Main beam connection section; 1a-Main beam splice section; 2-Side arch rib; 21-Groove; 3-Shear connector; 31-Transverse shear member; 32-Longitudinal shear member; 4-Stiffening rib; 41-Transverse stiffening rib; 42-Longitudinal stiffening rib; 5-Main arch; 6-Arch seat; 7-Suspension cable; 8-Column. Detailed Implementation

[0027] The present invention will now be described in further detail with reference to specific embodiments. However, this should not be construed as limiting the scope of the present invention to the following embodiments; all technologies implemented based on the content of the present invention fall within the scope of the present invention.

[0028] Unless otherwise specified, the use of terms such as "upper," "lower," "left," "right," "center," "inner," and "outer" to indicate orientation or positional relationships in the description of specific embodiments of the present invention is based on the orientation or positional relationships shown in the accompanying drawings, or the orientation or positional relationship in which the product / equipment / device is typically placed during use. These terms are merely for the purpose of facilitating the description of the present invention or simplifying the description in specific embodiments, enabling those skilled in the art to quickly understand the solution, and do not indicate or imply that a particular device / component / element must have a specific orientation, or be constructed and operated in a specific positional relationship. Therefore, they should not be construed as limitations on the present invention.

[0029] Furthermore, the use of terms such as "horizontal," "vertical," "suspended," and "parallel" does not imply that the corresponding device / component / element must be absolutely horizontal, vertical, suspended, or parallel, but rather that it can be slightly tilted or have a deviation. For example, "horizontal" merely means that its direction is more horizontal relative to "vertical," not that the structure must be completely horizontal, but that it can be slightly tilted. Alternatively, it can be simplified to mean that the corresponding device / component / element, when set in a "horizontal," "vertical," "suspended," or "parallel" direction, can have an error / deviation of ±10% relative to the corresponding direction, more preferably within ±8%, more preferably within ±6%, more preferably within ±5%, and more preferably within ±4%. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its function in the present invention.

[0030] Furthermore, the use of terms such as "first," "second," and "third" in terminology is merely for distinguishing descriptions of identical or similar components and should not be interpreted as emphasizing or implying the relative importance of a particular component.

[0031] Furthermore, in the description of the embodiments of the present invention, "several", "more than", and "a number of" represent at least two. The number can be any number, such as 2, 3, 4, 5, 6, 7, 8, or 9, and can even exceed nine.

[0032] Furthermore, in the description of the technical solution of this invention, unless otherwise explicitly specified / limited / restricted, the terms "set up," "install," "connect," "link," "provided with," "laid out," and "arranged" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to common connection methods in the art, such as welding, riveting, bolting, and threaded connections. Such connections can be mechanical, electrical, or communication connections; they can be direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components.

[0033] Example 1 like Figure 3 , Figure 4 , Figure 5 and Figure 6 The diagram shows the structure of the arch-beam joint area of ​​a swallow-shaped arch bridge, including a main beam connecting section 1 in the main beam of the swallow-shaped arch bridge. A side arch rib 2 is connected below the main beam connecting section 1. The side arch rib 2 has a groove 21 facing the main beam connecting section 1. The groove 21 is used to accommodate the main beam connecting section 1. The main beam connecting section 1 and the side arch rib 2 are connected by a shear connector 3. The shear connector 3 is set in the groove 21. Furthermore, the main beam connecting section 1 is a steel structure, while the side arch rib 2 is a concrete structure; Traditional swallow-shaped arch bridges are mostly load-bearing type. Specifically, a certain range at the end of the side arch rib 2 needs to be designed as a steel structure to form an integral structure with the main beam. In this way, the force transmission between the main beam and the side arch rib 2 is mainly achieved through the bearing pressure of the steel-concrete structure surface of the side arch rib 2. However, the force transmission of the swallow-shaped arch bridge is as follows: under the action of structural gravity and bridge deck load, the main arch 5 of the swallow-shaped arch bridge is compressed and tends to push outward, and transmits the force to the side arch rib 2, causing the side arch rib 2 to be compressed. Then, the force is transmitted to the main beam connected to the side arch rib 2, causing the main beam to be tensile, thus restraining the outward pushing tendency of the main arch rib 5 and reducing the thrust generated by the main arch 5. In this application, the side arch rib 2 is replaced with a concrete structure and connected to the main beam connection section 1 of the main beam through a shear connector 3. Due to the function of the shear connector 3, when the side arch rib 2 transmits force to the main beam, it is achieved through the shear connector 3, making the force transmission path clear.

[0034] In one or more embodiments, the main beam connecting section 1 is a hollow structure, and stiffening ribs 4 are provided on each surface inside the main beam connecting section 1. This can effectively reduce the self-weight of the main beam connecting section 1, reduce material usage and construction costs, and also improve the overall stiffness and stability of the main beam connecting section 1, enhance its bending, shear and torsional resistance, thereby ensuring the safety and reliability of the arch beam joint area during the stress process.

[0035] In one or more embodiments, the shear connector 3 includes a transverse shear member 31 located on the side wall of the groove 21. The shear connector 3 also includes a longitudinal shear member 32 located on the bottom surface of the groove 21. By setting the transverse shear member 31 on the side wall of the groove 21 and the longitudinal shear member 32 on the bottom surface of the groove 21, a reliable mechanical connection is formed between the main beam connecting section 1 and the side arch rib 2 in both the transverse and longitudinal directions. This can effectively disperse and transmit shear forces in different directions, improve the overall stress stability and shear resistance of the arch-beam joint area, and reduce the problem of local stress concentration caused by a single-direction connection. Furthermore, the shear connector 3 is connected to the main beam connection section 1 by welding, such as... Figure 4 and Figure 6 As shown.

[0036] In one or more embodiments, the stiffening rib 4 includes transverse stiffening ribs 41, which are symmetrically arranged and located on the inner sidewall of the main beam connection section 1. The stiffening rib 4 also includes longitudinal stiffening ribs 42, which are symmetrically arranged and located on the top and bottom surfaces inside the main beam connection section 1. The stiffening rib 4, comprising symmetrically arranged transverse stiffening ribs 41 and longitudinal stiffening ribs 42, respectively located on the inner sidewall, top surface, and bottom surface of the main beam connection section 1, not only uniformly enhances the stiffness and stability of the main beam connection section 1 in different directions, but also effectively improves its bending, shear, and torsional resistance, avoiding local structural deformation, thereby ensuring the safety and durability of the arch-beam joint area under complex loads. Figure 4 and Figure 6 As shown.

[0037] In this application, the main beam connecting section 1 is composed of a pair of web plates, a bottom plate and a top plate. The internal sidewall of the main beam connecting section 1 described in this application is the web plate, the bottom plate is the bottom surface inside the main beam connecting section 1, and the top plate is the top surface inside the main beam connecting section 1.

[0038] Example 2 like Figure 1 and Figure 2 The diagram illustrates a swallow-shaped arch bridge structure, including the arch-beam joint structure of Example 1. It includes a main arch 5 and two arch-beam joint structures, each connected to the main arch 5 via an arch seat 6. A main beam is connected below the main arch 5, connecting the main arch 5 to the arch-beam joint area. Optimized force transmission through the arch-beam joint area improves the overall structural stability of the swallow-shaped arch bridge. Specifically, under its own weight and the bridge deck load, the main arch 5 experiences compression and tends to push outwards, transmitting the force to the side arch ribs 2. The side arch ribs 2, after being compressed, transmit the force to the main beam connecting section 1 via shear connectors 3. The main beam connecting section 1 is under tension, thus constraining the outward pushing tendency of the main arch 5 and offsetting part of the thrust of the main arch 5.

[0039] In one or more embodiments, the main beam includes a main beam connecting section 1 and a main beam splice section 1a connected to the main beam connecting section 1. The top of the main beam splice section 1a is connected to the main arch 5 by a sling 7.

[0040] In one or more embodiments, the bottom of the main beam is connected to the side arch rib 2 and the arch seat 6 by a column 8.

[0041] In one or more embodiments, the arch seat 6 is fixedly connected to the main arch 5 and the side arch ribs 2.

[0042] Example 3 like Figure 7 , Figure 8 , Figure 9 and Figure 10 The method shown is a design method for the arch-beam joint zone structure of a swallow-shaped arch bridge, used to design the arch-beam joint zone structure of a swallow-shaped arch bridge in Embodiment 1, including: First, a finite element model of the flying swallow arch bridge is established, and the axial force of the main beam connection section 1 (i.e. the total shear force transmitted by the shear connection member 33 in the arch-beam joint area) is obtained through the finite element model. Several side arch ribs 2 are preset with their cross-sectional heights. The cross-sectional heights of each side arch rib 2 are substituted into the finite element model for calculation to obtain the force transmission path length between the main beam connection section 1 and the side arch rib 2 under each side arch rib 2 cross-sectional height (i.e., the arrangement range of the shear connection 3 in the arch-beam joint area). Based on the force transmission path length between the main beam connection section 1 and the side arch rib 2 at the height of each side arch rib 2 section, the ratio of the force transmission path length between the side arch rib 2 and the main beam connection section 1 and the side arch rib 2 is obtained. The finite element model of the arch bridge is divided into segments to obtain the number of shear connectors 3 in each segment; Simulation analysis was performed on the finite element model of the arch bridge to obtain the shear force distribution information of the shear force connector 3 per unit length; Based on the number of shear connectors 3 in each segment, the spacing between the shear connectors 3 in each segment is obtained.

[0043] Example 4 This embodiment is an application of the design method in Embodiment 3.

[0044] A finite element model of the swallow-shaped arch bridge was established to obtain the axial force of the main beam connection section 1, which is also the total shear force F transmitted by the shear connection member 3 in the arch-beam joint area. Through finite element analysis, the maximum axial tensile force of the main beam connection section 1 in this embodiment, that is, the total shear force F transmitted by the shear connection member 3 in the arch-beam joint area, is 116000kN. The force transmission path length between the main beam connection section 1 and the side arch rib 2 is set, which is also the arrangement range L of the shear connection 3 in the arch-beam joint area. Through finite element simulation calculation and numerical fitting, the force transmission path length L in the arch-beam joint area is obtained as 3.5H+2.0 (m), where H is the cross-sectional height of the side arch rib 2. In this embodiment, the height of the side arch rib 2 section is H=6.5m, and the length of the force transmission path between the main beam connection section 1 and the side arch rib 2, that is, the arrangement range L of the shear connection member 3 in the arch-beam joint area, is 3.5H+2.0=3.5×6.5+2.0=24.75 (m). The number N of shear connectors 3 in each section of the arch-beam joint zone was determined. Through extensive calculations and finite element fitting, the shear force V distribution per unit length of shear connectors 3 in the arch-beam joint zone was found to be approximately triangular. The shear force Vmax of the connectors near the main arch 5 was the largest, which was 2F / L. The number N of shear connectors 3 in the corresponding section was V / [Q], where [Q] is the allowable shear bearing capacity (kN) of a single shear connector 3. The shear force V distribution of the shear connectors 3 in the arch-beam joint zone was approximately triangular. The shear force Vmax of the connectors near the main arch 5 was the largest, which was 2F / L. In this embodiment, Vmax = 2 × 116000 / 24.75 = 9373 kN. The number of connectors required per unit length near the main arch 5 was N = V / [Q] = 9373 / 68.7 = 136 (pieces). In this embodiment, 25mm diameter stud connectors were used, and the allowable shear bearing capacity [Q] of a single connector was 68.7 kN. The number of shear connectors 3 in the remaining sections is determined according to the shear force borne by the connectors in the corresponding sections of the shear force distribution diagram; The spacing d of the shear connectors 3 in each section of the arch-beam joint zone is calculated. The spacing of the shear connectors 3 in each section is (n1+n2) / N, where n1 and n2 are the number of connectors arranged in the main beam connecting section 1, the web, and the flange, respectively. In this embodiment, the number of connectors arranged in the main beam connecting section 1, the web, and the flange, n1 and n2, are 20 and 10, respectively. The spacing d of the shear connectors 3 in the section of the arch-beam joint zone closest to the main arch 5 is N / (n1+n2) = (10+20) / 136 = 0.22m. The spacing of the shear connectors 3 in the remaining sections is determined according to the shear force borne by the connectors in the corresponding sections of the shear force distribution diagram. To simplify the connector arrangement scheme and facilitate construction, the arrangement of the shear connectors 3 in the arch-beam joint zone is divided into three sections from the main arch 5 side to the side arch side, with the spacing of the shear connectors 3 distributed as 0.2m, 0.25m, and 0.3m.

[0045] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A structural feature of the arch-beam junction area of ​​a swallow-shaped arch bridge, characterized in that: Includes a main beam connecting section (1), and a side arch rib (2) is connected below the main beam connecting section (1); The side arch rib (2) has a groove (21) on the side facing the main beam connecting section (1), and the side arch rib (2) is connected to the main beam connecting section (1) through the groove (21). The main beam connecting section (1) is provided with shear connectors (3) on the surface facing the groove (21). The main beam connecting section (1) is a steel structure, and the side arch rib (2) is a concrete structure.

2. The structure of the arch-beam joint zone of a swallow-shaped arch bridge according to claim 1, characterized in that, The main beam connecting section (1) is a hollow structure, and stiffening ribs (4) are provided on each surface inside the main beam connecting section (1).

3. The structure of the arch-beam joint zone of a swallow-shaped arch bridge according to claim 1, characterized in that, The shear connector (3) includes a transverse shear member (31), which is located on the side wall of the groove (21); The shear connector (3) further includes a longitudinal shear member (32), which is located on the bottom surface of the groove (21).

4. The structure of the arch-beam joint zone of a swallow-shaped arch bridge according to claim 2, characterized in that, The stiffening rib (4) includes a transverse stiffening rib (41), which is symmetrically arranged and located on the inner side wall of the main beam connection section (1). The stiffening rib (4) also includes a longitudinal stiffening rib (42), which is symmetrically arranged and located on the top and bottom surfaces inside the main beam connecting section (1).

5. The structure of the arch-beam joint zone of a swallow-shaped arch bridge according to claim 1, characterized in that, The shear connector (3) is connected to the main beam connection section (1) by welding.

6. A swallow-shaped arch bridge structure, characterized in that, The structure includes a flying swallow arch bridge arch beam joint area structure as described in any one of claims 1-5, and also includes a main arch (5). The arch beam joint area structure includes two structures, and each arch beam joint area structure is connected to the main arch (5) through an arch seat (6). The main arch (5) is connected to the main beam below.

7. The swallow-shaped arch bridge structure according to claim 6, characterized in that, The main beam includes the main beam connecting section (1) and the main beam splicing section (1a) connected to the main beam connecting section (1). The top of the main beam splicing section (1a) is connected to the main arch (5) by a sling (7).

8. The swallow-shaped arch bridge structure according to claim 6, characterized in that, The bottom of the main beam is connected to the side arch rib (2) and the arch seat (6) by a column (8).

9. The swallow-shaped arch bridge structure according to claim 6, characterized in that, The arch seat (6) is fixedly connected to the main arch (5) and the side arch rib (2).

10. A design method for the arch-beam joint zone structure of a swallow-shaped arch bridge, characterized in that, The design of the arch-beam joint zone structure of a swallow-shaped arch bridge as described in any one of claims 1-5 includes the following steps: Establish a finite element model of the arch bridge, and obtain the axial force of the main beam connection segment (1) based on the finite element model of the arch bridge; The cross-sectional heights of several of the aforementioned side arch ribs (2) are preset; Based on the finite element model of the arch bridge, the cross-sectional height of each side arch rib (2) is simulated to obtain the relationship between the length of the arrangement range of the shear connector (3) and the cross-sectional height of the side arch rib (2); The finite element model of the arch bridge is divided into segments to obtain the number of shear connectors (3) arranged in each segment; Simulation analysis was performed on the finite element model of the arch bridge to obtain the shear force distribution information of the shear connection member (3) per unit length; Based on the number of shear connectors (3) arranged in each segment, the arrangement spacing of the shear connectors (3) in each segment is obtained.

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