Net-shaped suspender tied-bar pedestrian arch bridge structure

Abstract

The utility model relates to the technical field of bridge engineering, in particular to a net-shaped suspender tie bar pedestrian arch bridge structure. Comprising a tie beam, an end cross beam, a middle cross beam and a longitudinal beam, the middle cross beam intersects with the longitudinal beam, the end of the middle cross beam is connected to the tie beam, the end of the longitudinal beam is connected to the end cross beam, and the end of the middle cross beam is connected to the end cross beam. The bridge deck is provided with a plurality of symmetrical tuned mass dampers. The arch rib and the straining beam are both made of seamless steel pipes, transverse partition plates and longitudinal stiffeners are not arranged, and the seamless steel pipes of the arch rib part adapt to the arch rib line type through the section cold bending technology. Web plates of the middle cross beams are welded with the straining beams; and the end cross beams are welded with the straining beams. And the fork lugs of the suspender are connected with the arch rib and the lifting lugs on the straining beam through pin shafts. The structural system can effectively reduce the volume and reduce the arrangement difficulty of anchoring parts.

Description

Technical Field

[0001] The utility model relates to the technical field of bridge engineering, in particular to a mesh-shaped hanger rod tie rod pedestrian arch bridge structure. Background Art

[0002] In the 1950s, Professor Tveit of Norway proposed the concept of a mesh-type tie-arch bridge. Compared with traditional vertical hangers or Nelson arch bridges, which have multiple intersections on the arch rib plane, the inclined hangers transfer the same load to a wider range of arch ribs. Its advantage is that it can significantly reduce the arch ribs, main beam bending moments, and the risk of the structure being compressed and unstable under asymmetric loads. Therefore, under the same conditions, the mesh-type hanger-type tie-arch bridge can play a greater economic advantage in structure.

[0003] At present, mesh hanger arch bridges have been used in many developed countries such as Japan, the United States, and Germany, but they still face some challenges in large-scale application in China. The main problems include: complex long-span structures. Due to the large scale (span, bridge width) of bridges in my country, the span of mesh hanger arch bridges is usually large, so the structure is more complex, and the design and construction difficulties increase. Heavy deadweight. Due to the structural characteristics, the deadweight of mesh hanger arch bridges is large, which not only increases the construction cost, but also puts higher requirements on the stability and bearing capacity of the bridge. The difficulty of arranging the cable and anchor system increases. In large-span bridges, the inclined hangers bear large dead loads, live loads, and stress amplitude effects, which increases the difficulty of arranging the cable and anchor system and limits the development of this type of bridge in large-scale applications. Utility Model Content

[0004] The purpose of the utility model is to provide a mesh-type hanger-tie-bar pedestrian arch bridge structure. By combining the advantages of the mesh-type hanger-tie-bar arch bridge system and the characteristics of pedestrian loads, the arch ribs, main beams and anchoring structures are optimized to achieve the purpose of simplifying the design and reducing the cost. At the same time, the overall shape of the structure is light and simple, with a small sense of volume, providing a new idea for the design of large-span pedestrian bridges.

[0005] In order to achieve the above purpose, the technical solution of the utility model is as follows:

[0006] A mesh hanger tie-bar pedestrian arch bridge structure comprises arch ribs, a mesh hanger system and a main beam, wherein the arch ribs and the main beam are connected to the mesh hanger system via an anchoring structure, a bridge deck is arranged above the main beam, the main beam is arranged in a transverse and longitudinal manner, and comprises a tie beam, an end cross beam, a middle cross beam and a longitudinal beam, the middle cross beam intersects with the longitudinal beam, the end of the middle cross beam is connected to the tie beam, the end of the longitudinal beam is connected to the end cross beam, and the bridge deck is provided with a plurality of symmetrical tuned mass dampers.

[0007] Furthermore, the arch ribs and tie beams are made of seamless steel pipes, without transverse partitions and longitudinal stiffeners, and the seamless steel pipes of the arch ribs are adapted to the arch rib line shape through segmental cold bending technology, simplifying the structural design while ensuring the appearance characteristics of the bridge.

[0008] Furthermore, the mesh suspension rod system includes a plurality of suspension rods, each of which is a steel strand cable. The upper and lower suspension points of different oblique directions have a 50mm transverse deviation to avoid cable collision.

[0009] Furthermore, the inclination angle of the arch rib is 15°, and the hanger is a 1860MPa steel strand cable.

[0010] Furthermore, the cross beam web of the middle cross beam is welded to the tie beam, and the end cross beam is welded to the full cross section of the tie beam.

[0011] Furthermore, the middle cross beam is an I-shaped fish belly cross beam, which mainly transmits vertical crowd load. The end cross beam box-shaped fish belly cross beam is used to transmit longitudinal forces such as temperature between the tie beam and the bridge deck. A longitudinal beam is set under the anisotropic steel bridge deck to disperse the live load effect of the crowd. The longitudinal and transverse beam system can improve the force transmission efficiency and reduce the deadweight of the structure.

[0012] Furthermore, the fork ears of the suspension rod are connected with the arch rib and the ears on the tie beam by pins to form an anchoring structure, thereby meeting the installation error and deformation requirements of the cable in the longitudinal and transverse directions of the bridge.

[0013] Furthermore, the middle cross beam is arranged at the lifting lug position of the tie beam.

[0014] Furthermore, tuned mass dampers are installed at the 1 / 4 symmetrical span position of the arch bridge, with a total of 4 locations on the entire bridge.

[0015] Furthermore, the pre-camber of the main beam is reasonably set, and the self-adjusting characteristics of the cable force of the system are utilized. After the hanger is tightened, the bottom bracket of the beam can be removed to achieve the drop frame. This avoids secondary cable adjustment and achieves the purpose of simplifying construction and accelerating construction progress.

[0016] Furthermore, a tuned mass damper (TMD) system is installed at the bottom of the main beam crossbeam. The parameters such as mass, stiffness, frequency, damping ratio and damping coefficient of the TMD system are determined according to the actual characteristics of the structure, achieving the vibration reduction effect of the large-span bridge, thereby improving the travel comfort.

[0017] The utility model has the following beneficial effects:

[0018] The difficulty of the anchoring system is mainly affected by the oblique boom, and in this design, the boom uses steel strand cables connected by pins to form an anchoring structure. This design not only simplifies the construction of the anchoring system, but also avoids the possibility of collision with the oblique boom, thereby reducing the difficulty of the anchoring system.

[0019] The use of seamless steel pipes as materials for arch ribs and tie beams, combined with segment cold bending technology, can adapt to the linear shape of the arch ribs and simplify the structural design. In addition, the use of I-shaped fish belly beams and box-shaped fish belly end beams as main beams can effectively transmit longitudinal forces such as pedestrian loads and temperature, while dispersing the live load effect of the crowd, improving the force transmission efficiency, and thus reducing the weight of the overall structure.

[0020] By using a tuned mass damper (TMD) system, structural resonance can be effectively suppressed and vibration acceleration can be reduced. The TMD system has a simple structure, reliable effects, and is easy to implement, thereby improving travel comfort. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a general layout diagram of an embodiment of the utility model;

[0022] Figure 2 This is the main beam plane layout form of an embodiment of the utility model;

[0023] Figure 3 This is a schematic diagram of the structure of the middle cross beam in one embodiment of the utility model;

[0024] Figure 4 This is a schematic diagram of the arch rib anchoring structure of an embodiment of the utility model;

[0025] Figure 5 A schematic diagram of a tie beam anchoring structure according to an embodiment of the utility model;

[0026] Figure 6 This is a structural diagram of a 1860MPa steel strand hanger rod according to an embodiment of the present utility model.

[0027] The numbers in the figure are: 1. arch rib; 2. tie beam; 3. end cross beam; 4. middle cross beam; 5. hanger; 6. longitudinal beam; 7. bridge deck; 8. lifting eye; 9. steel strand; 10. fork ear; 11. pin; 12. cross beam web; 13. tuned mass damper. DETAILED DESCRIPTION

[0028] The present invention is further described in detail below with reference to the accompanying drawings and specific examples. It should be noted that the accompanying drawings are in very simplified form and in non-precise proportions, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention. The above is only a description of the preferred embodiments of the present invention, and is not any limitation to the present invention. Any changes and modifications made by ordinary technicians in the field of the present invention based on the above disclosure are within the scope of protection of the claims.

[0029] See also Figure 1 , a footbridge adopts a mesh-suspended tie-arch structure, which includes arch ribs, suspenders and main beams. Figure 2As shown in the figure, the main beam adopts a longitudinal and transverse beam system, which includes tie beams, transverse beams, bridge decks and longitudinal beams. Figure 3 As shown in the figure, a tuned mass damper (TMD) system is installed at the bottom of the main beam, and the longitudinal beams are evenly arranged under the bridge deck. Figure 4 and 5 As shown, the anchorage on the beam and arch adopts the form of lug plates, such as Figure 6 As shown, the hanger adopts conventional 1860MPa steel strand cable.

[0030] In this embodiment, the main beam is composed of a tie beam 2, an end beam 3, a middle beam 4, a bridge deck 7 and a longitudinal beam 6. The “I”-shaped fish belly middle beam 4 is arranged at the position of the hanger, and a box-shaped fish belly beam 3 is arranged at the end. The web 12 of the middle beam 4 is welded to the tie beam 2, and the longitudinal beam 6 is evenly arranged under the bridge deck system 7 to disperse the live load effect of the crowd.

[0031] In this embodiment, the inclined hanger arch and tie beam anchoring structures are both in the form of ear plates 8, and the ears are welded to the arch rib 1 and tie beam 2 respectively to ensure the firmness of the anchoring. To avoid the inclined hangers 5 crossing, the upper and lower hangers 5 have a 50mm transverse deviation to ensure the construction accuracy.

[0032] In this embodiment, the arch rib 1 is designed with an inward inclination of 15° and is in the form of a seamless steel pipe, which is adapted to the arch rib line shape by segment cold bending technology. The hanger 5 is made of conventional 1860MPa steel strand cable, and its fork ear 10 is connected to the hanger ear 8 on the arch rib 1 and the tie beam 2 by a pin 11 to ensure a stable connection.

[0033] In this embodiment, the tuned mass damper (TMD) system: a tuned mass damper (TMD) 13 is installed at the 1 / 4 symmetrical span position, with a total of 4 locations on the entire bridge. The mass, stiffness, frequency, damping ratio and damping coefficient of the TMD system are determined according to the actual characteristics of the structure. By comparing the acceleration response of the structure before and after the installation of the device, the vibration reduction rate reaches 89.7%, which effectively improves the comfort and safety of the bridge.

[0034] In this embodiment, the construction method of first beam and then arch is adopted, and the main beam and arch rib 1 are both constructed with few brackets. By utilizing the self-adjusting characteristics of the mesh hanger system and reasonably setting the pre-arch of the main beam, the bottom bracket of the beam can be removed after the hanger 5 is tensioned, and the frame can be dropped, which simplifies the construction process.

Claims

1. A mesh-suspender-tied pedestrian arch bridge structure, comprising an arch rib (1), a mesh-suspender system and a main beam, characterized in that: The arch rib (1) and the main beam are connected to the mesh hanger system through an anchoring structure. The bridge deck (7) is arranged above the main beam. The main beam is arranged in a horizontal and vertical direction and includes a tie beam (2), an end cross beam (3), a middle cross beam (4) and a longitudinal beam (6). The middle cross beam (4) intersects with the longitudinal beam (6). The end of the middle cross beam (4) is connected to the tie beam (2), and the end of the longitudinal beam (6) is connected to the end cross beam (3). The bridge deck (7) is provided with a plurality of symmetrical tuned mass dampers (13).

2. The meshed suspension rod tied arch pedestrian bridge structure according to claim 1 is characterized in that: The mesh hanger system comprises a plurality of hangers (5), wherein the hangers (5) are steel strand cables.

3. The meshed suspension rod-tied pedestrian arch bridge structure according to claim 1 is characterized in that: The inclination angle of the arch rib (1) is 15°, and the hanger (5) is a 1860MPa steel strand cable.

4. The meshed suspension rod-tied pedestrian arch bridge structure according to claim 1 is characterized in that: The cross beam web (12) of the middle cross beam (4) is welded to the tie beam (2), and the end cross beam (3) is welded to the tie beam (2) over the entire cross section.

5. The meshed suspension rod tied arch pedestrian bridge structure according to claim 4 is characterized in that: The middle cross beam (4) is an I-shaped fish belly cross beam, and the end cross beam (3) is a box-shaped fish belly cross beam.

6. The meshed suspension rod-tied pedestrian arch bridge structure according to claim 1 is characterized in that: The fork ears (10) of the suspension rod (5) are connected to the arch rib (1) and the suspension ears (8) on the tie beam (2) by means of a pin (11) to form an anchoring structure.

7. The meshed suspension rod-tied pedestrian arch bridge structure according to claim 6 is characterized in that: The middle cross beam (4) is arranged at the position of the lifting lug (8) of the tie beam (2).

8. The meshed suspension rod-tied pedestrian arch bridge structure according to claim 1 is characterized in that: Tuned mass dampers are installed at the 1 / 4 symmetrical span position of the arch bridge, with a total of 4 locations on the entire bridge.

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