Vortex vibration suppression device for suppressing vortex vibration of large-span flexible bridge

Abstract

The invention relates to the technical field of bridge engineering and wind engineering, and discloses a vortex-induced vibration suppression device for suppressing vortex-induced vibration of a large-span flexible bridge, comprising a flexible guide plate which is arranged at a tuyere part on the anchoring side of an asymmetric steel box bridge and is connected with the end part of the tuyere; the flexible guide plates are continuously arranged on the whole bridge in the longitudinal direction of the bridge; the flexible flow guide plate is arranged to replace a traditional rigid flow guide plate, the flexible flow guide plate can absorb vortex energy generated when flow passes through the section of the asymmetric steel box bridge through vibration and deformation of the flexible flow guide plate under the action of airflow, and the response speed to wind speed changes is high; and even if the flexible guide plate is slightly deformed, the flexible guide plate can still adapt to the deformation so as to suppress the vortex vibration, has the advantages of being high in adaptability and good in vortex vibration suppression effect, and can be widely applied to pneumatic optimization design of large-span flexible bridge vortex vibration. And the situations that the pedestrian safety is influenced by wind load and the service life of the bridge structure is shortened can be avoided.

Description

Technical Field

[0001] The invention relates to a vortex vibration suppression device for suppressing vortex vibration of a long-span flexible bridge, and belongs to the technical field of bridge engineering and wind engineering. Background Art

[0002] Bridge vortex vibration is a resonance phenomenon caused by wind on a bridge. This vibration usually occurs in the longitudinal or transverse direction of the bridge and is related to the interaction between the natural frequency of the bridge and the wind speed. At present, large-span flexible bridges are easily affected by wind loads due to their light weight, flexibility and low damping characteristics, resulting in wind-induced vibration phenomena such as vortex-induced vibration. Vortex vibration not only threatens the safety of the bridge structure, but also may reduce its service life and affect the comfort of vehicles and pedestrians on the bridge.

[0003] For this reason, in the prior art, guide plates are often installed on bridges to improve the bridge's vortex-induced vibration resistance. However, the guide plates currently installed on bridges are all rigid guide plates, such as the invention patent application with Chinese patent application number 201810497199.1, which improves the wind resistance of the bridge in different wind environments and reduces the wind-induced vibration amplitude of the bridge structure by installing rigid guide plates on the bridge. Another example is the utility model patent with Chinese patent application number 201320843049.4, which also changes the air flow characteristics of the closed steel box girder bridge by installing rigid guide plates on the bridge, so that its vortex-induced resonance can be significantly controlled.

[0004] However, the rigid guide plate has the following problems in actual use: 1. Under the action of wind, the bridge will deform to a certain extent. Due to its rigid structure, the rigid guide plate is difficult to adjust its position according to the slight deformation of the bridge, and may not be able to follow these deformations well, resulting in its actual effect of suppressing vortex vibration being relatively general.

[0005] 2. Due to its rigid structure, the rigid guide vane responds slowly to changes in wind speed and may not be able to adjust its position in time to cope with rapidly changing wind conditions, resulting in limited effect in suppressing vortex vibration.

[0006] Research has shown that flexible deflectors can more effectively suppress vortex-induced vibration responses and adapt to complex and variable wind environments due to their material deformability and low stiffness. However, there is still little research and application of flexible deflectors, so there is an urgent need for a deflector device that combines flexible materials and innovative designs to improve the anti-vortex-induced vibration capability of asymmetric steel box bridges. Summary of the invention

[0007] In order to solve the above problems existing in the prior art, the present invention provides a vortex-vibration suppression device for suppressing vortex-vibration of a long-span flexible bridge.

[0008] The technical solution of the present invention is as follows: A vortex vibration suppression device for suppressing vortex vibration of a large-span flexible bridge includes a flexible guide plate. The flexible guide plate is arranged at the wind nozzle position on the anchoring side of an asymmetric steel box bridge and is connected to the end of the wind nozzle. The flexible guide plate is also continuously arranged on the entire bridge along the longitudinal direction of the bridge.

[0009] Furthermore, the cross section of the flexible guide plate is arranged in a rectangular structure.

[0010] Furthermore, the flexible guide plate is made of polymer composite material.

[0011] Furthermore, the flexible guide plate is composed of a plurality of segments, and each flexible guide plate segment is connected to an adjacent flexible guide plate segment by filling with adhesive.

[0012] Furthermore, a guide plate fixing bracket is provided at the wind nozzle position on the anchoring side of the asymmetric steel box bridge, and the flexible guide plate is connected to the wind nozzle end by being installed on the guide plate fixing bracket, and a damping energy absorption layer is also provided between the flexible guide plate and the guide plate fixing bracket.

[0013] Furthermore, the flexible guide plate is arranged on the end of the air nozzle in an inclined downward manner.

[0014] Furthermore, the damping energy absorbing layer is made of elastic material, and the dynamic energy dissipation coefficient of the damping energy absorbing layer is greater than 0.8.

[0015] The present invention has the following beneficial effects: The present invention replaces the traditional rigid guide plate with a flexible guide plate. Compared with the rigid guide plate, the flexible guide plate can absorb the eddy current energy generated by the flow passing through the asymmetric steel box bridge section through its own vibration and deformation under the action of airflow. It has a fast response speed to changes in wind speed, and even with slight deformation, the flexible guide plate can still adapt to such deformation to suppress vortex vibration. It has strong adaptability and good effect of suppressing vortex vibration. At the same time, when suppressing vortex vibration, the flexible guide plate can also dissipate the eddy current energy faster through its own vibration and deformation, thereby significantly reducing the vortex vibration response. Moreover, compared with the rigid guide plate, the flexible guide plate is more convenient to install and maintain, which can reduce the difficulty of construction and can be directly used for the renovation of existing bridges. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A top view of the present invention; Figure 2 It is a structural detail diagram of the present invention; Figure 3 is an axonometric view of the present invention; Figure 4 It is a front view of the present invention; Figure 5 It is a rear view of the present invention; Figure 6 This is a comparison chart of the vertical displacement and the reduction of vertical displacement of the flexible guide plate and the rigid guide plate under the +3° working condition; Figure 7 The figure is a comparison of the torsional displacement and the reduction of torsional displacement of the flexible guide plate and the rigid guide plate under the condition of +3° angle of attack; Figure 8 This is a comparison chart of the torsional displacement and the reduction of torsional displacement at an angle of attack of -3° between the flexible guide plate and the rigid guide plate.

[0017] The reference numerals in the figure are as follows: 1. Flexible guide plate; 2. Asymmetric steel box bridge; 3. Wind nozzle; 4. Damping energy absorption layer; 5. Guide plate fixing bracket. DETAILED DESCRIPTION

[0018] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0019] Example: Please refer to Figures 1 to 5 The present embodiment provides a vortex vibration suppression device for suppressing vortex vibration of a large-span flexible bridge, including a flexible guide plate 1. The flexible guide plate 1 is arranged at the wind nozzle 3 on the anchoring side of the asymmetric steel box bridge 2 and is connected to the end of the wind nozzle 3 so as to be able to absorb the eddy current energy generated by the convection passing through the cross-section of the asymmetric steel box bridge 2, that is, the wind nozzle 3. The flexible guide plate 1 is also continuously arranged on the entire bridge along the longitudinal direction of the bridge so as to be able to suppress the vortex vibration of the entire bridge.

[0020] In this embodiment, the cross-section of the flexible guide plate 1 is set to a rectangular structure. The flexible guide plate 1 with a rectangular cross-section can effectively interfere with the airflow, reduce the shedding of vortices, and thus reduce the occurrence of vortex vibration.

[0021] In this embodiment, the flexible guide plate 1 is made of a polymer composite material, which can be a common silicone rubber or polyurethane material. The flexible guide plate 1 made of a polymer composite material has deformable characteristics and good fatigue resistance. Compared with the traditional rigid guide plate, the flexible guide plate 1 has different effects and action mechanisms. The flexible guide plate 1 reduces its own stiffness through the polymer composite material so that it has vibrations and deformations that are not synchronized with the asymmetric steel box bridge 2 structure. Under the action of airflow, it can absorb the eddy current energy generated by the flow through the cross-section of the asymmetric steel box bridge 2 through its own vibration and deformation. It responds quickly to changes in wind speed, and even with slight deformation, the flexible guide plate 1 can still adapt to such deformations to suppress vortex vibrations. It has strong adaptability and good vortex vibration suppression effect. At the same time, when the flexible guide plate 1 suppresses vortex vibrations, it can also dissipate the vortex energy faster through its own vibration and deformation, thereby significantly reducing the vortex vibration response.

[0022] In this embodiment, the flexible guide plate 1 is composed of several segments, and the specific segments can be determined according to the actual situation. Each segment of the flexible guide plate 1 is connected with the adjacent segment of the flexible guide plate 1 by filling with adhesive. The above-mentioned setting can not only facilitate the construction, but also facilitate the subsequent replacement of the flexible guide plate 1.

[0023] In this embodiment, a guide plate fixing bracket 5 is also provided at the wind nozzle 3 on the anchoring side of the asymmetric steel box bridge 2. The flexible guide plate 1 is fixedly connected to the end of the guide plate 3 by being installed on the guide plate fixing bracket 5. A damping energy absorbing layer 4 is also provided between the flexible guide plate 1 and the guide plate fixing bracket 5. The damping energy absorbing layer 4 is used to absorb the energy of the vibration of the flexible guide plate 1 itself, so as to weaken the influence of the vibration of the flexible guide plate 1 on the asymmetric steel box bridge 2. The damping energy absorbing layer 4 is an elastic material, which can be common butyl rubber, polyisobutylene, etc. The dynamic energy dissipation coefficient of the damping energy absorbing layer 4 is greater than 0.8, so as to be able to well absorb the energy of the vibration of the flexible guide plate 1 itself and reduce the transmission of this energy to the asymmetric steel box bridge 2.

[0024] In this embodiment, the flexible guide plate 1 is arranged at an angle downward on the end of the wind nozzle 3. The vortex vibration suppression device works at about 10°. Therefore, the inclination angle of the flexible guide plate 1 is 10°. In actual use, the specific inclination angle can be adjusted according to the bridge design requirements. The flexible guide plate 1 arranged at an angle downward can not only guide the airflow to flow more effectively along the surface of the asymmetric steel box bridge 2, reduce the vortex and turbulence generated by the airflow on the asymmetric steel box bridge 2, thereby reducing the occurrence of vortex vibration, but also increase the contact area between the airflow and the flexible guide plate 1, enhance the damping effect of the airflow, and enable the damping energy absorption layer 4 to more effectively absorb and dissipate the energy generated by the vibration of the flexible guide plate 1. The width and thickness of the flexible guide plate 1 can also be adjusted according to the bridge design requirements. In this embodiment, the width of the flexible guide plate 1 is 700-800 mm and the thickness is 10 mm.

[0025] Please refer to Figures 6 to 8 , Figure 6 It is a comparison diagram of the vertical displacement and the reduction of the vertical displacement of the flexible guide plate 1 and the rigid guide plate under the +3° working condition; Figure 7 It is a comparison diagram of the torsional displacement and the reduction of torsional displacement at the angle of attack of the flexible guide plate 1 and the rigid guide plate under the condition of +3°; Figure 8 It is a comparison chart of the torsional displacement and the reduction amplitude of torsional displacement at the angle of attack of the flexible guide plate 1 and the rigid guide plate under the working condition of -3°. Under the working condition of +3°, the vertical displacement and the reduction amplitude of the vertical displacement of the asymmetric steel box bridge 2 are significantly reduced when the flexible guide plate 1 is compared with the rigid guide plate. In the experimental data under the working condition of -3°, the torsional displacement and the reduction amplitude of torsional displacement at the angle of attack of the asymmetric steel box bridge 2 are significantly reduced when the flexible guide plate 1 is compared with the rigid guide plate. In the experimental data under the working condition of +3°, the torsional displacement and the reduction amplitude of torsional displacement at the angle of attack of the asymmetric steel box bridge 2 are not significantly reduced when the flexible guide plate 1 is compared with the rigid guide plate, indicating that there is almost no negative impact. Therefore, it can be explained that the present invention has an inhibitory effect on the vortex-induced vibration of the large-span asymmetric steel box bridge 2. At the same time, it can also be obtained that the preferred width of the flexible guide plate 1 is 700mm.

[0026] It should be noted that, in this application, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0027] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features applied for herein.

Claims

1. A vortex vibration suppression device for suppressing vortex vibration of a long-span flexible bridge, characterized in that: The invention comprises a flexible guide plate (1), wherein the flexible guide plate (1) is arranged at a wind nozzle (3) on the anchoring side of an asymmetric steel box bridge (2) and is connected to the end of the wind nozzle (3), and the flexible guide plate (1) is continuously arranged on the entire bridge along the longitudinal direction of the bridge.

2. The vortex vibration suppression device for suppressing vortex vibration of a long-span flexible bridge according to claim 1 is characterized in that: The cross section of the flexible guide plate (1) is arranged in a rectangular structure.

3. The vortex vibration suppression device for suppressing vortex vibration of a long-span flexible bridge according to claim 1 is characterized in that: The flexible guide plate (1) is made of a polymer composite material.

4. The vortex vibration suppression device for suppressing vortex vibration of a long-span flexible bridge according to claim 1 is characterized in that: The flexible guide plate (1) is composed of a plurality of segments, and each flexible guide plate (1) segment is connected to an adjacent flexible guide plate (1) segment by filling with adhesive.

5. The vortex vibration suppression device for suppressing vortex vibration of a long-span flexible bridge according to claim 1 is characterized in that: A guide plate fixing bracket (5) is also provided at the wind nozzle (3) on the anchoring side of the asymmetric steel box bridge (2); the flexible guide plate (1) is connected to the end of the wind nozzle (3) by being installed on the guide plate fixing bracket (5); and a damping energy absorbing layer (4) is also provided between the flexible guide plate (1) and the guide plate fixing bracket (5).

6. The vortex vibration suppression device for suppressing vortex vibration of a long-span flexible bridge according to claim 5, characterized in that: The flexible guide plate (1) is arranged on the end of the air nozzle (3) in an inclined manner downward.

7. The vortex vibration suppression device for suppressing vortex vibration of a long-span flexible bridge according to claim 5, characterized in that: The damping energy absorbing layer (4) is made of elastic material, and the dynamic energy dissipation coefficient of the damping energy absorbing layer (4) is greater than 0.8.

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