Fabricated overline overbridge and construction method thereof

Abstract

The invention relates to the field of bridge construction, in particular to a fabricated overline overbridge and a construction method thereof.The fabricated overline overbridge comprises a side span, and the side span is connected with a roadbed through a bridge abutment; the two ends of the main span are connected with side spans respectively, the side spans are of concrete structures, the main span is of a steel-concrete combined structure, each side span comprises a main beam, one end of each main beam is connected with the bridge abutment, the other end of each main beam is connected with the corresponding main span, inclined-leg supporting beams are arranged below the main beams, the inclined-leg supporting beams are obliquely arranged below the main beams, one end of each inclined-leg supporting beam is connected with the bottom of the corresponding main beam, and the other end of each inclined-leg supporting beam is connected with an embedded base; due to the fact that the main span is of the steel-concrete combined structure, a support does not need to be erected below the main span to support the main span in the follow-up erecting process, the space below the main span in the construction period is released, passing of vehicles or pedestrians under the bridge is guaranteed, the self weight of the main span of the steel-concrete combined structure is small, and the supporting effect is good. And the bearing capacity is high, so that the beam height of the main span is reduced, and the main span under-bridge clearance is further expanded.

Description

Technical Field

[0001] The invention relates to the technical field of bridge construction, in particular to an assembled overpass and a construction method thereof. Background Art

[0002] In the field of bridge engineering, overpasses are usually used to cross facilities such as roads or railways. They are often set up at places where pedestrians, bicycles and other vehicles need to cross highways or first-class highways, especially in places where traffic conflicts are serious, such as stations, large commercial centers or other intersections. Inclined leg rigid frames are commonly used structural forms for overpasses, but currently inclined leg rigid frame overpasses mostly use full concrete structures, that is, they are built by concrete main beams and concrete inclined leg piers. During the construction process, the pouring of concrete main beams and inclined leg piers requires the erection of brackets, but the erection of brackets will occupy too much space under the bridge during the construction process, especially the brackets erected under the main span during the construction process, which directly hinder the normal passage of vehicles and pedestrians under the bridge. And because the entire bridge is a concrete structure, the tensile performance of concrete materials is poor, so the length ratio of the side span to the middle span must be not less than 0.5 to ensure the reasonable overall force performance of the structure. The increase in the side-to-middle span ratio of the concrete inclined leg rigid frame will inevitably lead to the expansion of the inclined leg in the direction of the main span, which reduces the clearance under the main span bridge. In addition, the concrete material itself is heavy. In order to ensure the spanning capacity of the main span, the beam height of the concrete main beam is large, which further compresses the clearance under the main span bridge. There are also steel-concrete composite structure beam bridges in the existing bridges. The side span and main span of this bridge are both steel-concrete composite structures. Compared with traditional concrete bridges, steel-concrete composite structure bridges combine steel structure main beams with concrete bridge decks, which reduces the deadweight of the structure. In addition, no support is required during the construction process, and the construction is fast. However, conventional steel-concrete composite structure beam bridges use vertical or nearly vertical piers. As the clearance demand under the bridge increases, it can only be achieved by increasing the span. The increase in span requires further increasing the cross-section of the main beam to meet the needs of higher bending stiffness and bearing capacity. When the cross-section of the main beam increases exponentially with the increase in span, it not only increases the material consumption of the main beam and piers, but also reduces the clearance under the bridge, limiting the use scenario. Summary of the invention

[0003] The purpose of the present invention is to address the existing traditional concrete inclined leg rigid frame bridge in the prior art. During the construction process, it is necessary to set up a support frame under the main span to occupy the space under the bridge, which hinders the normal passage of vehicles or pedestrians under the bridge. In addition, due to the poor tensile performance of concrete materials, in order to achieve reasonable force, the inclined leg piers at both ends are often extended toward the main span, thereby compressing the clearance under the main span. The main span and side span of the traditional steel-concrete composite structure beam bridge are both steel-concrete composite structures. When the span of the bridge increases, the cross-sectional area of ​​the main span needs to be increased to meet the needs of sufficient bending stiffness and bearing capacity, thereby reducing the problem of clearance under the bridge. Provided is an assembled overpass and a construction method thereof.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is:

[0005] In a first aspect, an assembled overpass includes a side span, the side span being connected to a roadbed through an abutment; and a main span, both ends of the main span being connected to the side span through a concrete transition section, the side span being a concrete structure, and the main span being a steel-concrete composite structure;

[0006] The side span includes a main beam, one end of the main beam is connected to the abutment, and the other end is connected to the main span. An inclined leg support beam is provided below the main beam. The inclined leg support beam is obliquely arranged below the main beam, and one end is connected to the bottom of the main beam, and the other end is connected to an embedded seat. The inclined leg support beam is fixedly connected to the roadbed slope through the embedded seat.

[0007] The present invention is an assembled overpass, which is composed of a concrete side span, a concrete transition section and a main span of a steel-concrete composite structure. Since the main span in the present application is a steel-concrete composite structure, there is no need to set up a bracket under the main span to support it during the subsequent construction process, which releases the space under the main span during construction and ensures the passage of vehicles or pedestrians under the bridge. In addition, the main span of the steel-concrete composite structure has a smaller deadweight than that of the concrete structure. On the basis of ensuring that it has the same spanning capacity as the concrete main span, the beam height of the main span of the steel-concrete composite structure is reduced, further expanding the clearance under the bridge of the main span. Compared with the traditional steel-concrete composite structure beam bridge, the present invention Please use a concrete side span to support the main span. The arrangement of the main beam and the inclined legs in the side span of the bridge can effectively decompose the vertical load and horizontal thrust from the main span. The horizontal thrust is guided to the embedded seats and abutments, and finally transmitted to the roadbed and the roadbed slope, ensuring the stability of the bridge. At the same time, the horizontal thrust generated by the inclined legs of the side span generates pre-stress in the main span, thereby reducing the shear force and bending moment in the main span. The main span adopts a steel-concrete composite structure with a higher bearing capacity, so that the main span can further reduce the beam height without sacrificing the bearing capacity. The reduction in beam height further expands the clearance under the bridge.

[0008] As a preferred solution of the present invention, a reinforcement section is provided at the connection between the inclined leg support beam and the main beam.

[0009] The structural stability of the side span is ensured by setting up reinforcement sections.

[0010] As a preferred solution of the present invention, the main span and the two concrete transition sections constitute a middle span.

[0011] As a preferred embodiment of the present invention, the ratio of the length of the concrete transition section to the length of the middle span is 0.15 to 0.2.

[0012] As a preferred embodiment of the present invention, the angle between the main beam and the oblique leg support beam is 30° to 60°.

[0013] As a preferred solution of the present invention, the ratio of the length of the main beam to the length of the middle span is 0.35 to 0.8.

[0014] Compared with the background technology in which the length ratio of the side span to the middle span of the traditional concrete slanted leg rigid frame bridge is not less than 0.5, the length ratio of the side span to the middle span of the present application can be smaller. When the bridge length is the same, the length of the middle span of the present application is greater than the length of the middle span of the traditional concrete slanted leg rigid frame bridge, so that the length of the side span of the present application is less than the length of the side span of the traditional concrete slanted leg rigid frame bridge, thereby increasing the length of the middle span and increasing the clearance under the bridge; and because the main span connected to the side span of the present application is a steel-concrete composite structure, it is lighter in weight, and the pre-pressure generated by the horizontal thrust generated by the slanted leg support beam in the main span reduces the shear force and bending moment in the main span, thereby further reducing the main span beam height and increasing the clearance under the main span bridge.

[0015] As a preferred solution of the present invention, the main span comprises a steel beam, and a concrete layer is provided above the steel beam.

[0016] By configuring the main span in the form of a steel beam plus a concrete layer, the main span in this application is different from the traditional concrete main span, which reduces its own weight and speeds up construction efficiency.

[0017] As a preferred solution of the present invention, the steel beam is an I-beam.

[0018] The I-beam has a simple structure and can be prefabricated in the factory and then hoisted on site, eliminating the need to erect supports during the construction of traditional concrete inclined-leg rigid frames, thereby speeding up construction, reducing construction interference, and improving construction efficiency.

[0019] As a preferred solution of the present invention, a first type of joint is provided between both ends of the concrete layer and the concrete transition section, and the first type of joint is used to connect the concrete layer and the concrete transition section.

[0020] By setting the first type of joints between the two ends of the concrete layer and the concrete transition section, the concrete layer and the concrete transition section can be effectively connected to form an integral force-bearing unit. The first type of joint provides good interface bonding performance during concrete pouring, which can effectively transfer the load from the concrete layer, reduce interface slip, and improve the integrity and rigidity of the bridge structure; in addition, the setting of wet joints can absorb and adjust minor deformations caused by temperature changes, shrinkage and creep, avoid stress concentration, and extend the service life of the structure.

[0021] As a preferred solution of the present invention, the concrete layer includes a plurality of concrete panels arranged at intervals, and a second type of joint is provided between two adjacent concrete panels, and the second type of joint is used to connect the two adjacent concrete panels.

[0022] By setting the second type of joints between adjacent concrete panels, a stable connection between the panels can be effectively achieved, avoiding structural weakening and cracking caused by relative displacement between the panels. The second type of joints form a well-integrated connection interface during pouring, which can evenly transfer horizontal and vertical loads, improve the integrity and stress performance of the concrete layer; the second type of joints can absorb the slight deformation of the panel caused by temperature changes, shrinkage and creep, prevent stress concentration, and extend the service life of the structure.

[0023] As a preferred solution of the present invention, a shear nail groove is vertically provided on the concrete panel, and the shear nail groove runs through the concrete panel.

[0024] By vertically setting shear nail grooves on the concrete panel and running them through the entire panel, the shear connection performance between the bridge deck and the steel beam can be significantly improved. The shear nail grooves provide a fixing and force-bearing channel for the shear nails, allowing the load to be efficiently transferred from the concrete panel to the steel beam, enhancing the collaborative working ability of the overall structure.

[0025] In a second aspect, a construction method of an overpass is provided for constructing the above-mentioned assembled overpass, the method comprising:

[0026] S1. Set abutments and embedded seats on the roadbed and roadbed slope respectively;

[0027] S2. Set up the inclined leg bracket and the main beam bracket, and cast the inclined leg support beam, the main beam and the concrete transition section through the inclined leg bracket and the main beam bracket;

[0028] S21. After the main beam is cast, it is connected to the abutment. After the inclined leg beam is cast, it is connected to the embedded seat.

[0029] S3. Remove the main beam support and keep the inclined leg support;

[0030] S4. Use the suspension bridge equipment on the concrete transition section to lift the steel beam to the same level as the concrete transition section, and securely connect the concrete transition section to the steel beam;

[0031] S5. Arrange a concrete layer on the steel beam and connect the concrete layer with the concrete transition section;

[0032] S6. Remove the inclined leg supports and the suspension bridge equipment, and the construction is completed.

[0033] As a preferred solution of the present invention, retaining the inclined leg support in S3 specifically includes: retaining the inclined leg support located below the concrete transition section.

[0034] The present invention is a construction method for a flyover. The method first constructs a main beam support and an inclined leg support for constructing a main beam and an inclined leg support beam. In the present application, the main span is a steel-concrete composite structure composed of a steel beam and a concrete layer, which is light in weight. The main beam and the inclined leg support beam are cast-in-place concrete structures, so that the length of the main beam itself is shorter than that of a traditional concrete inclined leg rigid frame during design. Therefore, when constructing the main beam support and the inclined leg support, less space under the bridge is occupied. During construction, more space can be provided for the normal passage of vehicles or pedestrians under the main span bridge compared to the traditional concrete inclined leg rigid frame. In the present application, the main beam support is first removed and the inclined leg support is retained. This operation enables the inclined leg support to serve as a temporary support. When the steel beam is subsequently erected, stable support is provided for the side span main beam and the inclined leg, so that the steel beam is lifted and fixed on the main beam by the suspension bridge equipment, and there is no need to set up other devices on the ground. This ensures the overall structural stability during the construction of the main span and ensures that the space under the main span bridge is not occupied during construction.

[0035] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0036] 1. The present invention is an assembled overpass, which is composed of a concrete side span, a concrete transition section and a main span of a steel-concrete composite structure. Since the main span in the present application is a steel-concrete composite structure, there is no need to set up a bracket under the main span to support it during the subsequent construction process, which releases the space under the main span during construction and ensures the passage of vehicles or pedestrians under the bridge. The main span of the steel-concrete composite structure has a smaller deadweight than that of the concrete structure. On the basis of ensuring that it has the same spanning capacity as the concrete main span, the beam height of the main span main beam of the steel-concrete composite structure can be reduced, further expanding the main span under the bridge clearance. Compared with the steel-concrete composite structure beam bridge, the present invention Please use a concrete side span to support the main span. The arrangement of the side span main beam and the inclined legs can effectively decompose the vertical load and horizontal thrust from the main span. The horizontal thrust is guided to the embedded seats and abutments, and finally transmitted to the roadbed and the roadbed slope, ensuring the stability of the bridge. At the same time, the horizontal thrust generated by the side span inclined leg support beam generates prestress in the main span, which reduces the shear force and bending moment in the main span. The main span adopts a steel-concrete composite structure with a higher bearing capacity, so that the main span can further reduce the beam height without sacrificing the bearing capacity. The reduction in beam height further expands the clearance under the bridge.

[0037] 2. The present invention is a construction method for a flyover. The method first constructs a main beam support and an inclined leg support for constructing a main beam and an inclined leg support beam. In the present application, the main span is a steel-concrete composite structure composed of a steel beam and a concrete layer, which is light in weight. The main beam and the inclined leg support beam are cast-in-place concrete structures, so that the length of the main beam itself is shorter than that of a traditional concrete inclined leg rigid frame during design. Therefore, when constructing the main beam support and the inclined leg support, less space is occupied under the bridge. During construction, more space can be provided for the normal passage of vehicles or pedestrians under the main span bridge compared to traditional concrete inclined leg rigid frames. In the present application, the main beam support is first dismantled and only the inclined leg support is retained to provide stable support for the side span main beam and the inclined leg, so that the steel beam is lifted and fixed on the main beam by the suspension bridge equipment, and there is no need to set up other devices on the ground. This not only ensures the overall structural stability during the construction of the main span, but also ensures that the space under the main span bridge is not occupied during construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a structural schematic diagram of the assembled overpass of the present invention;

[0039] Figure 2 It is a schematic diagram of the structure of the mid-span of the present invention;

[0040] Figure 3 The present invention Figure 1 A magnified image of point A;

[0041] Figure 4 It is a schematic diagram of the main span structure of the present invention;

[0042] Figure 5 It is a structural schematic diagram of a concrete layer of the present invention;

[0043] Figure 6 is a top view schematic diagram of a concrete layer of the present invention connected to a first type of joint;

[0044] Figure 7 It is a schematic diagram of the connection between the side span and the oblique leg support and the main beam support of the present invention;

[0045] Figure 8 is a schematic diagram of the present invention after the main beam support is disassembled;

[0046] Fig. 9 It is a schematic diagram of installing a steel beam according to the present invention;

[0047] Fig.10 is a schematic diagram of installing a concrete panel of the present invention;

[0048] Fig.11 is a schematic diagram of casting the first type of joint and the second type of joint of the present invention;

[0049] Fig.12 It is a flow chart of the construction method of the overpass of the present invention.

[0050] Icons: 1-side span; 11-main beam; 12-inclined leg support beam; 2-abutment; 3-main span; 31-steel beam; 32-concrete layer; 321-concrete panel; 3211-shear nail groove; 322-second-type joint; 4-embedded seat; 5-first-type joint; 6-reinforcement section; 7-inclined leg support; 8-main beam support; 9-concrete transition section; 10-middle span; 20-roadbed; 30-roadbed slope. DETAILED DESCRIPTION

[0051] The present invention is further described in detail below in conjunction with specific embodiments. However, this should not be understood as the scope of the above subject matter of the present invention being limited to the following embodiments, and all technologies realized based on the content of the present invention belong to the scope of the present invention.

[0052] Unless otherwise specified, in the description of the specific embodiments of the present invention, the terms indicating the orientation or position relationship such as "up", "down", "left", "right", "center", "inside", "outside", etc. are based on the orientation or position relationship when the invented product / equipment / device is usually used. These terms of orientation or position relationship are only for the convenience of describing the scheme of the present invention or simplifying the description in the specific embodiments to facilitate the technicians to quickly understand the scheme, rather than indicating or implying that a specific device / component / element must have a specific orientation, or be constructed and operated in a specific position relationship, and therefore cannot be understood as a limitation of the present invention.

[0053] In addition, if the terms "horizontal", "vertical", "overhanging", "parallel" and the like appear, it does not mean that the corresponding devices / components / elements are required to be absolutely horizontal or vertical or overhanging or parallel, but may be slightly tilted or have deviations. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but may be slightly tilted. Alternatively, it can be simplified to mean that the corresponding devices / components / elements are set in directions such as "horizontal", "vertical", "overhanging", "parallel", etc., and can have an error / deviation of ±10% relative to the corresponding direction setting, more preferably an error / deviation within ±8%, more preferably an error / deviation within ±6%, more preferably an error / deviation within ±5%, and more preferably an error / deviation within ±4%. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its role in the scheme of the present invention.

[0054] In addition, the expressions “first”, “second”, “third”, etc., which appear in the terms, are merely used to distinguish the description of the same or similar components and should not be understood as emphasizing or implying the relative importance of specific components.

[0055] In addition, in the description of the embodiments of the present invention, "several", "plurality" and "a number" represent at least 2. It can be any number such as 2, 3, 4, 5, 6, 7, 8, 9, and even more than 9.

[0056] In addition, in the description of the technical solution of the present invention, unless otherwise clearly specified / defined / restricted, the terms "set", "install", "connect", "connected", "provided with", "laid", and "arranged" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection, and can be welding, riveting, bolting, threading, and other commonly used connection means in the field. This connection can be a mechanical connection, an electrical connection, or a communication connection; it can be a direct connection, or an indirect connection through an intermediate medium, and it can be the internal connection of two elements.

[0057] Example 1

[0058] like Figure 1 , Figure 2 and Figure 3 The assembled overpass shown in the figure comprises a side span 1, which is connected to a roadbed 20 through an abutment 2; and a main span 3, both ends of which are connected to the side span 1 through concrete transition sections 9, the side span 1 is a concrete structure, and the main span 3 is a steel-concrete composite structure;

[0059] The side span 1 includes a main beam 11, one end of the main beam 11 is connected to the abutment 2, and the other end is connected to the main span 3. An inclined leg support beam 12 is provided below the main beam 11. The inclined leg support beam 12 is obliquely arranged below the main beam 11, and one end is connected to the bottom of the main beam 11, and the other end is connected to the embedded seat 4. The inclined leg support beam 12 is fixedly connected to the roadbed slope 30 through the embedded seat 4. The side span 1 composed of concrete is connected to the main span 3 composed of a steel-concrete structure. Since the main span 3 of the steel-concrete composite structure is composed of steel and concrete parts, there is no need to build a support for casting. During construction, the main span 3 can be directly hoisted on the concrete transition section 9, which can ensure the normal passage of vehicles or pedestrians under the bridge. Moreover, since the side span 1 is a concrete structure, and the side span 1 is provided with an inclined leg support beam 12 that can be connected to the main beam 11, the inclined setting of the inclined leg support beam 12 can make the main span The bridge load generated by 3 is transmitted to the embedded seat 4 through the inclined leg support beam 12 and finally transmitted to the roadbed slope 30 to offset the horizontal displacement trend. At the same time, the horizontal thrust generated by the inclined leg support beam 12 generates pre-stress in the main span 3. The pre-stress reduces the shear force and bending moment in the main span 3, improves the structural safety and service life, and enhances the overall force efficiency and structural stability. In addition, as the span increases, since the concrete side span 1 can provide pre-stress for the main span 3, the main span 3 in this application does not need to ensure the bearing capacity by increasing its own cross-sectional area like the main span 3 of the traditional steel-concrete structure bridge; the main span 3 in this application is a steel-concrete composite structure. Since its own weight is lighter than that of concrete, and it is connected with the side span 1 composed of a concrete structure, the main span 3 can effectively reduce its own cross-sectional area, further improving the clearance under the bridge.

[0060] The inclined setting of the side span 1 of the present application enables the bridge load generated by the main span 3 to be transmitted to the embedded seat 4 through the inclined leg support beam 12 and finally to the roadbed slope 30 to offset the horizontal displacement trend. At the same time, the horizontal thrust generated by the inclined leg support beam 12 generates pre-stress in the main span 3, which reduces the shear force and bending moment in the main span 3, improves the structural safety and service life, and enhances the overall force efficiency and structural stability.

[0061] In the present application, the concrete transition section 9 and the main beam 11 are cast in one piece.

[0062] In one or more embodiments, a reinforcement section 6 is provided at the connection between the oblique leg support beam 12 and the main beam 11. The reinforcement section 6 ensures the structural stability of the side span 1 and strengthens the concrete transition section 9 connecting the main span and the side span. Figure 1 shown.

[0063] In one or more embodiments, the angle between the main beam 11 and the oblique leg support beam 12 is 30° to 60°;

[0064] Furthermore, the main span 3 and the two concrete transition sections 9 form a middle span 10, and the length ratio of the main beam 11 to the middle span 10 is 0.35-0.8. Compared with the background technology, the length ratio of the side span to the middle span of the concrete inclined leg rigid frame bridge is not less than 0.5. The length ratio of the side span to the middle span of the present application can be smaller. When the bridge length is the same, the length of the main span 3 of the present application is greater than the length of the traditional concrete inclined leg rigid frame main span 3, so that the length of the side span 1 of the present application is less than the length of the traditional concrete inclined leg rigid frame side span 1, which increases the length of the middle span 10 and increases the clearance under the bridge; and because the main span 3 connected to the side span 1 of the present application is a steel-concrete composite structure, it is lighter, and the pre-pressure generated by the inclined leg support beam 12 acting on the main span 3 can further reduce the beam height of the main span 3, such as Figure 1 and Figure 2 shown.

[0065] In one or more embodiments, the main span 3 includes a steel beam 31, and a concrete layer 32 is provided above the steel beam 31. By configuring the main span 3 as a steel beam 31 plus a concrete layer 32, the main span 3 in the present application is different from the traditional concrete inclined leg rigid frame main span 3, and its own deadweight is reduced. The steel beam 31 can be prefabricated in the factory and then hoisted on site. During the construction process, no support is required under the main span 3. This not only gives play to the excellent stress-bearing performance of the steel-concrete composite structure, but also further reduces the deadweight of the structure, speeds up the construction speed, and reduces construction interference. Figure 4 and Figure 5 shown.

[0066] In one or more embodiments, the steel beam 31 is an I-beam.

[0067] The I-beam has a simple structure and can be prefabricated in the factory and then hoisted on site, eliminating the need to erect supports during the construction of traditional concrete inclined-leg rigid frames, thereby speeding up construction, reducing construction interference, and improving construction efficiency.

[0068] In one or more embodiments, a first type of joint 5 is provided between the two ends of the concrete layer 32 and the concrete transition section 9. The first type of joint 5 is used to connect the concrete layer 32 and the concrete transition section 9. By providing the first type of joint 5 between the two ends of the concrete layer 32 and the concrete transition section 9, the concrete layer 32 and the concrete transition section 9 can be effectively connected to form an integral force-bearing unit. The first type of joint 5 provides good interface bonding performance during concrete pouring, can effectively transfer the load from the concrete layer 32, reduce interface slip, and improve the integrity and rigidity of the bridge structure; in addition, the setting of the wet joint can absorb and adjust the slight deformation caused by temperature changes, shrinkage and creep, etc., avoid stress concentration, and extend the service life of the structure, such as Figure 3 and Figure 6 shown.

[0069] In one or more embodiments, the concrete layer 32 includes a plurality of concrete panels 321 arranged at intervals, and a second type of joint 322 is provided between two adjacent concrete panels 321. The second type of joint 322 is used to connect two adjacent concrete panels 321. By providing the second type of joint 322 between adjacent concrete panels 321, a stable connection between the panels can be effectively achieved, and structural weakening and cracking caused by relative displacement between the panels can be avoided. The second type of joint 322 forms a connection interface with good integrity during pouring, which can evenly transfer horizontal and vertical loads, and improve the integrity and force-bearing performance of the concrete layer 32; the second type of joint 322 can absorb the slight deformation of the panel caused by temperature changes, shrinkage and creep, etc., to prevent stress concentration and extend the service life of the structure;

[0070] Furthermore, a shear nail groove 3211 is vertically provided on the concrete panel 321, and the shear nail groove 3211 runs through the concrete panel 321. By vertically providing the shear nail groove 3211 on the concrete panel 321 and running through the entire panel, the shear connection performance between the panel and the main span steel beam 31 can be significantly improved. The shear nail groove 3211 provides a fixing and force-bearing channel for the shear nail, so that the load can be efficiently transferred from the concrete panel 321 to the main span steel beam 31, enhancing the collaborative working ability of the overall structure and giving full play to the excellent force-bearing performance of the steel-concrete composite structure, such as Figure 5 and Figure 6 shown.

[0071] Taking the fixed mid-span length L as an example, the following table shows the comparison of the beam height of this application and the traditional concrete inclined leg rigid frame, as shown in Table 1:

[0072] Table 1

[0073]

[0074] The above table shows that in the case of a fixed middle span L, when the main span is a concrete structure, the beam height of the main span is L / 20~L / 25, and when the side span is a concrete structure, the beam height of the side span is L / 15~L / 20, that is, the main span beam height of the traditional concrete inclined leg rigid frame is L / 20~L / 25, and the side span beam height is L / 15~L / 20; when the main span is a steel-concrete composite structure, the main span beam height is L / 25~L / 30, and when the side span is a concrete structure, the side span beam height is L / 15~L / 20, that is, the main span beam height of the present application is L / 25~L / 30, and the side span beam height is L / 15~L / 20. Compared with the traditional concrete inclined leg rigid frame, the main span beam height of the present application is reduced by nearly 20%, which can increase the height of the clearance under the bridge.

[0075] Example 2

[0076] like Figure 7 , Figure 8 , Fig. 9 , Fig.10 , Fig.11 and Fig.12 The construction method of a flyover shown is used to construct the above-mentioned assembled flyover, and the method includes:

[0077] S1, respectively setting abutments 2 and embedded seats 4 on the roadbed 20 and the roadbed slope 30;

[0078] S2, erecting the oblique leg support 7 and the main beam support 8, and casting the concrete transition section 9 and the side span 1 in situ through the oblique leg support 7 and the main beam support 8;

[0079] S21, after pouring is completed, the side span 1 is connected with the abutment 2 and the embedded seat 4;

[0080] S3, remove the main beam support 8 and keep the oblique leg support 7;

[0081] S4, activating the suspension bridge equipment on the main beam 11 to lift the steel beam 31 to the level of the main beam 11, and fixing the main beam 11 to the steel beam 31;

[0082] S5, a concrete panel 321 is arranged on the steel beam 31, and the steel beam 31 and the concrete panel 321 are integrated into a whole through the shear nail groove 3211, and the concrete panel 321 is connected through the second type of joint to form a concrete layer 32, and finally the concrete layer 32 is connected to the concrete transition section 9 through the first type of joint 5;

[0083] S6. Remove the inclined leg support 7 and the suspension bridge equipment, and the construction is completed.

[0084] This method first builds a main beam support 8 and an inclined leg support 7 for constructing the main beam 11 and the inclined leg support beam 12, and the main span 3 in this application is a steel-concrete composite structure composed of a steel beam 31 and a concrete layer 32, which is light in weight, and the main beam 11 and the inclined leg support beam 12 are cast-in-place concrete structures, so that the length of the main beam 11 itself is shorter than that of the traditional concrete inclined leg rigid frame during design, so when building the main beam support 8 and the inclined leg support 7, less space under the bridge is occupied, and during construction, more space can be provided for the normal passage of vehicles or pedestrians under the main span bridge compared to the traditional concrete inclined leg rigid frame, and in this application, the main beam support 8 is first dismantled and only the inclined leg support 7 is retained. This operation enables the inclined leg support 7 to serve as a temporary support. When the steel beam 31 is subsequently erected, the steel beam 31 is lifted and fixed on the main beam 11 by the suspension bridge equipment, and there is no need to set up other devices on the ground, which not only ensures the stability of the side span 11 during construction, but also ensures that the space under the bridge is not occupied during construction.

[0085] In this application, the suspension bridge equipment is a suspension bridge machine.

[0086] In the present application, the first type of seams 5 and the second type of seams 322 may be wet seams.

[0087] In the present application, a steel plate is pre-embedded in one end of the concrete transition section 9 facing the main span 3 , and is connected to the steel beam 31 of the main span 3 via the pre-embedded steel plate.

[0088] The above are only 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 in the protection scope of the present invention.

Claims

1. An assembled overpass, characterized in that: The invention comprises a side span (1), wherein the side span (1) is connected to a roadbed (20) via an abutment (2); and a main span (3), wherein both ends of the main span (3) are connected to the side span (1) via a concrete transition section (9), wherein the side span (1) is a concrete structure, and the main span (3) is a steel-concrete composite structure; The side span (1) comprises a main beam (11), one end of the main beam (11) is connected to the abutment (2), and the other end is connected to the main span (3), an inclined leg support beam (12) is provided below the main beam (11), the inclined leg support beam (12) is obliquely arranged below the main beam (11), one end of the inclined leg support beam is connected to the bottom of the main beam (11), and the other end is connected to an embedded seat (4), and the inclined leg support beam (12) is fixedly connected to the roadbed slope (30) through the embedded seat (4).

2. The assembled overpass according to claim 1, characterized in that: A reinforcement section (6) is provided at the connection between the oblique leg support beam (12) and the main beam (11).

3. The assembled overpass according to claim 2, characterized in that: The main span (3) and the two concrete transition sections (9) form a middle span (10).

4. The assembled overpass according to claim 3, characterized in that: The ratio of the length of the main beam (11) to the length of the middle span (10) is 0.35 to 0.

8.

5. The assembled overpass according to claim 4, characterized in that: The main span (3) comprises a steel beam (31), and a concrete layer (32) is provided above the steel beam (31).

6. The assembled overpass according to claim 5, characterized in that: The steel beam (31) is an I-beam.

7. The assembled overpass according to claim 6, characterized in that: A first type of joint (5) is provided between the two ends of the concrete layer (32) and the concrete transition section (9), and the first type of joint (5) is used to connect the concrete layer (32) and the concrete transition section (9).

8. The assembled overpass according to claim 7, characterized in that: The concrete layer (32) comprises a plurality of concrete panels (321) arranged at intervals, a second type joint (322) is provided between two adjacent concrete panels (321), and the second type joint (322) is used to connect the two adjacent concrete panels (321).

9. The assembled overpass according to claim 8, characterized in that: A shear nail groove (3211) is vertically provided on the concrete panel (321), and the shear nail groove (3211) passes through the concrete panel (321).

10. A construction method for an overpass, characterized in that: The method for constructing an assembled overpass as claimed in any one of claims 5 to 9 comprises: S1, respectively setting a bridge abutment (2) and an embedded seat (4) on a roadbed (20) and a roadbed slope (30); S2, erecting the inclined leg support (7) and the main beam support (8), and casting the inclined leg support beam (12), the main beam (11) and the concrete transition section (9) in situ through the inclined leg support (7) and the main beam support (8); S21, after the main beam (11) is cast, it is connected to the abutment (2), and after the inclined leg support beam (12) is cast, it is connected to the embedded seat (4); S3, remove the main beam support (8) and retain the oblique leg support (7); S4, activating the suspension bridge equipment on the concrete transition section (9) to lift the steel beam (31) to the same level as the concrete transition section (9), and fixing the concrete transition section (9) and the steel beam (31); S5, arranging a concrete layer (32) on the steel beam (31), and connecting the concrete layer (32) and the concrete transition section (9); S6. Remove the inclined leg support (7) and the suspension bridge equipment, and the construction is completed.

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