A method and system for mitigating wind-induced vibrations of a bridge

Abstract

The present application relates to the technical field of inhibiting bridge wind-induced vibration, and particularly to a method and system for reducing bridge wind vibration. The method for reducing bridge wind vibration comprises the following steps: symmetrically hinged on both sides of the main girder of the bridge with respect to the central axis of the main girder, a plurality of damping plates are arranged, the damping plates can swing about the normal line of the main girder, the damping plates comprise A-type plates and B-type plates, the A-type plates and the B-type plates are arranged at intervals on the same side of the bridge, and the types of the damping plates on both sides of the main girder correspond to each other; the wind vibration frequency f of the bridge is obtained; the damping plates start to swing, the A-type plates swing at the frequency f, the B-type plates swing at the frequency (i+0.5)f, and the initial swing directions of the damping plates on different sides are opposite; after t minutes, it is judged whether the bridge is in the state of wind-induced vibration, if the bridge is still in the state of wind-induced vibration, the swinging of the damping plates is continued until the wind-induced vibration of the bridge stops; and if the wind-induced vibration of the bridge has stopped, the swinging of the damping plates stops.

Description

Technical Field

[0001] This invention relates to the technical field of suppressing wind-induced vibrations of bridges, and in particular to a method and system for mitigating wind-induced vibrations of bridges. Background Technology

[0002] Aerodynamic and mechanical measures are the main means of suppressing wind-induced vibration in bridges. Mechanical measures to suppress vortex-induced vibration of the main girder are extremely expensive to implement and maintain. Aerodynamic measures, on the other hand, are less costly and less burdensome, making them a more economical and reasonable alternative to damping measures, and are currently the most widely used method for controlling wind-induced vibration.

[0003] Pneumatic measures include both passive and active control.

[0004] Passive control improves the wind resistance of long-span bridges by altering the aerodynamic shape of the main girder cross-section or adding auxiliary components. Due to its simplicity and economy, this method is widely used in practical engineering, such as with deflectors, central stabilizing plates, and vents. However, passive control measures, based on two-dimensional cross-sectional flow field analysis, cannot flexibly control aerodynamic measures according to wind speed, wind direction, and bridge vibration status. While they effectively disrupt the incoming wind field, they cannot fully adapt to complex and variable natural wind environments, limiting their application. Furthermore, the need to install control devices along the entire span of the main girder significantly increases costs.

[0005] Active control, through cleverly designed mechanical structures, enables movement in what was originally a stationary passive control mechanism, achieving vibration control and thus having a wider range of applications. Therefore, active control is now widely used to suppress wind-induced vibration in bridges. However, existing active control devices require pre-setting and cannot adapt to wind-induced vibrations of different frequencies. Summary of the Invention

[0006] The purpose of this invention is to address the problem that existing technologies using pneumatic active control methods to suppress wind-induced vibrations of bridges require pre-setting of relevant active control devices, thus failing to adapt to wind-induced vibrations of different frequencies. This invention provides a method and system for mitigating wind-induced vibrations of bridges.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0008] A method for mitigating wind-induced vibration in bridges includes the following steps:

[0009] S1. Several damping plates are symmetrically hinged on both sides of the main beam about the central axis of the main beam. The damping plates can swing about the normal of the main beam. The damping plates include Class A plates and Class B plates. Class A plates and Class B plates are staggered on the same side of the bridge. The types of damping plates on both sides of the main beam are corresponding.

[0010] S2. Obtain the wind vibration frequency f of the bridge;

[0011] S3. Control the damping plate to start swinging; Class A plate... The Class B plate oscillates at a frequency of (i+0.5)f, and the initial oscillation directions of the damping plates on different sides are opposite, where i=0,1,2…n;

[0012] S4. After the damping plate starts to swing for t minutes, determine whether the bridge is in a state of wind-induced vibration. If the bridge is still in a state of wind-induced vibration, continue to control the swing of the damping plate until the wind-induced vibration of the bridge stops; if the wind-induced vibration of the bridge has stopped, the damping plate stops swinging.

[0013] If the damping plate can oscillate about the normal to the main beam, then the damping plate can oscillate vertically. The types of damping plates on both sides of the main beam correspond; that is, if one side of the main beam is a type A plate, then the other side symmetrical about the central axis of the main beam is also a type A plate. Step S3 can also be replaced by the type A plate oscillating at a frequency of (i+0.5)f, and the type B plate oscillating at a frequency of... The vibration damping plates oscillate at a frequency that is opposite to that of the damping plates on different sides. That is, if the initial oscillation direction of one side is clockwise, then the initial oscillation direction of the other side is counterclockwise.

[0014] The damping plates on both sides of the main beam are symmetrically arranged about the central axis of the main beam, and the types of damping plates on both sides are also symmetrical about the central axis. Therefore, when the damping plates swing, the vibration frequency applied to the main beam by the damping plates on both sides is consistent. This can minimize structural fatigue or even deformation of the main beam caused by inconsistent vibration frequencies on both sides, or situations that may affect the safety of vehicles traveling on the bridge. If the swing frequencies of the two sets of damping plates are different, two sets of vortices with different frequencies can be generated. When the swing frequency of the damping plates has a harmonic or half-frequency relationship with the wind vibration frequency f of the bridge, it is easy to cause the bridge vibration to intensify; when the swing frequency of the damping plates has a multiple of (i+0.5) (i=0,1,2,3……) with the wind vibration frequency f, it is more likely to cause the bridge vibration to intensify. When the relationship is (i = 0, 1, 2, 3...), the damping plate will not resonate with the bridge at the same frequency. The periodic force generated by the vortices that periodically detach from the damping plate will have a better suppressive effect on the bridge vibration. The initial swing direction of the damping plates on different sides is opposite because the damping plate generates vortices when it swings, which allows the damping plate to generate two types of vortices in different directions. This causes the bridge to be subjected to both vertically upward and vertically downward lift forces at the same time, thereby maximizing the balance of forces on the bridge in the vertical direction.

[0015] As a preferred embodiment of the present invention, a step of determining whether the bridge is in a state of wind vibration is included between step S2 and step S1.

[0016] Determine whether the bridge is in a state of wind vibration. If the bridge is not in a state of wind vibration, then the subsequent steps of obtaining the wind vibration frequency and controlling the swing of the damping plate are not performed, which helps to save costs.

[0017] As a preferred embodiment of the present invention, the steps for determining whether a bridge is in a state of wind-induced vibration are as follows:

[0018] I. Obtain the wind-induced vibration displacement of the bridge and the corresponding time.

[0019] II. Perform Fourier transform on the vibration displacement of the bridge and the time corresponding to the displacement to obtain the frequency domain signal of the bridge vibration.

[0020] III. If the frequency domain signal of bridge vibration has a dominant frequency, it indicates that the bridge has wind-induced vibration, and the dominant frequency is taken as the wind vibration frequency f; if the frequency domain signal of bridge vibration does not have a dominant frequency, it indicates that the bridge does not have wind-induced vibration.

[0021] The dominant frequency is the frequency that occurs most frequently during random vibration. If there is no dominant frequency in the frequency domain signal, it indicates that the bridge is not experiencing periodic vibration and therefore is not experiencing wind-induced vibration. If there is a dominant frequency in the frequency domain signal, it indicates that the structure is experiencing periodic vibration and that the bridge is experiencing wind-induced vibration.

[0022] As a preferred embodiment of the present invention, in step S1, the damping plate can also be hingedly installed on the outer edge of the two sides of the bridge tower perpendicular to the transverse direction of the bridge.

[0023] A system for mitigating wind-induced vibration in bridges, comprising:

[0024] The frequency acquisition module is used to acquire the wind vibration frequency f of the bridge;

[0025] The vibration damping module contains multiple vibration damping plates, including Class A plates and Class B plates. The vibration damping plates are symmetrically arranged on both sides of the main beam or on the outer edges of the two sides of the bridge tower perpendicular to the transverse direction of the bridge, with the central axis of the main beam as the axis. The vibration damping plates can swing about the normal of the main beam. Class A plates and Class B plates on the same side are staggered. The vibration damping plates on both sides of the main beam or the bridge tower at the same transverse position are of the same type.

[0026] The control module receives the frequency f from the frequency acquisition module and controls the Class A board according to the wind vibration frequency f. The B-type plate oscillates at a frequency of (i+0.5)f, while the initial oscillation direction of the damping plates on the same side is controlled to be the same, where i=0,1,2…n;

[0027] The frequency acquisition module signal is connected to the control module, and the control module signal is connected to the vibration reduction module.

[0028] The control module can also control Class A boards. The Class B plate oscillates at a frequency of (i+0.5)f, while the Class B plate oscillates at a frequency of (i+0.5)f. The frequency acquisition module obtains f and transmits it to the control module. The control module obtains the relevant frequency that can interfere with the wind-induced vibration of the bridge based on f and transmits this frequency signal to the vibration damping module. This causes the damping plate of the vibration damping module to oscillate according to the frequency transmitted by the control module, thereby interfering with the wind-induced vibration of the bridge. Compared with the existing technology of pre-set active control devices, this system can control the oscillation frequency of the vibration damping module according to the wind vibration frequency of the bridge, and can be applied to complex wind environments.

[0029] As a preferred embodiment of the present invention, the frequency acquisition module includes:

[0030] The vibration time history acquisition module is used to acquire the vibration displacement of the bridge and the corresponding time.

[0031] The signal conversion module is used to receive the signal transmitted by the vibration time history acquisition module, and perform Fourier transform on the vibration displacement of the bridge and the time corresponding to the displacement to obtain the frequency domain signal of the bridge vibration.

[0032] The judgment module receives the frequency domain signal transmitted by the signal conversion module and determines whether the bridge is in a wind-induced vibration state. If so, it extracts the dominant frequency of the frequency domain signal as the wind vibration frequency f and sends it to the control module; otherwise, it does not send a signal.

[0033] The vibration time history acquisition module's signal is connected to the signal conversion module, the signal conversion module's signal is connected to the judgment module, and the judgment module's signal is connected to the control module.

[0034] Because the bridge's vibration frequency changes after the vibration damping module oscillates, it's necessary to first determine if the bridge is experiencing wind-induced vibration to decide whether to proceed with subsequent steps. If the bridge is not experiencing wind-induced vibration, the determination module does not send a signal to the control module, meaning neither the control module nor the vibration damping module operates, thus saving on control costs.

[0035] As a preferred embodiment of the present invention, the height h of the damping plate is 0.15-0.3 times the height H of the main beam or the longitudinal dimension of the bridge tower, and the length l of the damping plate is 1-3 times h. The A-type plate and the B-type plate have the same size and structure.

[0036] The height of the damping plate is its vertical dimension, and its length is its horizontal dimension. The height h of the damping plate is 0.15-0.3 times the height H of the main beam. This minimizes the risk of ineffective damping due to insufficient height, while also preventing damage to the bridge structure from excessive height. Having the same dimensions and structure for Class A and Class B plates ensures vertical stress balance in the main beam, further minimizing damage to the bridge structure.

[0037] As a preferred embodiment of the present invention, the center distance between two adjacent Class A plates and Class B plates is 1.5-4 times their own length l. The damping plate is initially set along the cross-section of the main beam or the cross-section of the bridge tower. The maximum swing angle of the damping plate relative to the cross-section of the main beam or the cross-section of the bridge tower is ±30° and the minimum swing angle is ±10°.

[0038] The center distance between Class A and Class B boards should be 1.5-4 times their respective lengths (l). Too small a distance would cause collisions, while too large a distance would result in poor control. The swing angle is positive clockwise and negative counter-clockwise.

[0039] As a preferred embodiment of the present invention, a piezoelectric sheet is provided on the surface of the vibration damping plate.

[0040] When a piezoelectric element is installed on the surface of a vibration damping plate, the plate is easily subjected to slight deformation and vibration by wind when it is in its original position. The piezoelectric element fixed to the plate will generate periodic strain with the deformation and vibration of the plate. When the plate swings, the piezoelectric element will also be subjected to periodic pressure with the periodic swing of the plate, thereby outputting a periodic voltage. By utilizing the positive piezoelectric effect of the piezoelectric material, mechanical energy can be converted into electrical energy, achieving the effect of power generation.

[0041] In a preferred embodiment of the present invention, the frequency acquisition module includes a displacement sensor, which is installed at a critical location on the main beam or a critical location on the bridge tower.

[0042] The signal conversion module includes intelligent control motors, which are divided into Group A intelligent control motors and Group B intelligent control motors. Group A intelligent control motors are used to control Class A panels, and Group B intelligent control motors are used to control Class B panels. The intelligent control motors are located at the ends of the main beam or at the ends of the two sides of the bridge tower perpendicular to the transverse direction of the bridge.

[0043] The key locations of the main beam include the longitudinal 1 / 2, 1 / 4, and 3 / 4 positions of the main beam, and the key locations of the bridge tower include the top position of the bridge tower.

[0044] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0045] 1. A method for mitigating wind-induced vibration of bridges, comprising first obtaining the wind vibration frequency of the bridge, and then adjusting the sway frequency of the bridge's damping plates according to the wind vibration frequency, making the damping method applicable to bridges with different wind vibration frequencies. The damping plates are divided into two groups, and the two groups of damping plates are respectively adjusted according to… The vibration damping plate oscillates at a frequency of (i+0.5)f, preventing it from resonating with the bridge at the same frequency. The periodic force generated by the vortexes that periodically detach from the damping plate will better suppress the bridge vibration. This solves the problem that existing technologies that use aerodynamic measures to suppress wind-induced vibration of bridges require pre-setting of relevant active control devices, and therefore cannot adapt to wind-induced vibrations of different frequencies.

[0046] 2. A system for mitigating wind-induced vibration of bridges, comprising a frequency acquisition module, a control module, and a vibration reduction module. The control module controls the oscillation frequency of the vibration reduction module based on the signal transmitted by the frequency acquisition module. This solves the problem that existing technologies using pneumatic active control methods to suppress wind-induced vibration of bridges require pre-setting of relevant active control devices, thus failing to adapt to wind-induced vibrations of different frequencies. Attached Figure Description

[0047] Figure 1 This is a flowchart of a method for mitigating wind-induced vibration in bridges, as described in Example 1.

[0048] Figure 2 This is a schematic diagram of the module logic connection of a system for mitigating wind vibration of bridges in Embodiment 2;

[0049] Figure 3 This is a diagram showing the arrangement of the damping plates in Example 2 (the diagram is a top view).

[0050] Figure 4 This is the working state of the vibration damping plate in Example 2. Figure 1 ;

[0051] Figure 5 This is the working state of the damping plate in Example 2. Figure 2 ;

[0052] Figure 6 This is an arrangement of a system for mitigating wind-induced vibration in bridges, as shown in Example 2. Figure 1 ;

[0053] Figure 7 This is an arrangement of a system for mitigating wind-induced vibration in bridges, as shown in Example 2. Figure 2 ;

[0054] Figure 8 This is a flow field diagram of a system for mitigating wind-induced vibration of bridges in Example 2.

[0055] Figure 9 This is a diagram illustrating the operational effect of a system for mitigating wind-induced vibration in bridges, as shown in Example 2.

[0056] Figure 10 This is a front view of the vibration damping plate in Example 2. Figure 1 ;

[0057] Figure 11 This is a top view of the damping plate in Example 2. Figure 1 ;

[0058] Figure 12 This is the formal version of the vibration damping plate in Example 3. Figure 2 ;

[0059] Figure 13 This is a front view of the damping plate in Example 3. Figure 2 ;

[0060] Figure 14 The flow field in Example 3 Figure 1 ;

[0061] Figure 15 The flow field in Example 3 Figure 2 ;

[0062] Figure 16 The flow field in Example 3 Figure 3 .

[0063] Icons: 1-Vibration damping plate, 2-Intelligent control motor, 101-Class A plate, 102-Class B plate, 103-Group A intelligent control motor, 104-Group B intelligent control motor, 105-Connecting component, 106-Rotating bearing, 107-Circuit, 108-Displacement sensor, 109-Piezoelectric element, 110-Cylinder. Detailed Implementation

[0064] The present invention will now be described in detail with reference to the accompanying drawings.

[0065] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0066] Example 1

[0067] like Figure 1 As shown, a method for mitigating wind-induced vibration in bridges includes the following steps:

[0068] S1. Several damping plates 1 are symmetrically hinged on both sides of the main beam about the central axis of the main beam. The damping plates 1 can swing about the normal of the main beam. The damping plates 1 include type A plates 101 and type B plates 102. Type A plates 101 and type B plates 102 are set at intervals on the same side of the bridge. The types of damping plates 1 on both sides of the main beam are corresponding.

[0069] S2. Obtain the wind vibration frequency f of the bridge;

[0070] S3. Control the vibration damping plate 1 to start swinging, and Class A plate 101... The B-type plate 102 oscillates at a frequency of (i+0.5)f, and the initial oscillation directions of the damping plates 1 on different sides are opposite. In this embodiment, the oscillation frequency of the A-type plate 101 is .

[0071] S4. After the damping plate 1 starts to swing for t minutes, it is determined whether the bridge is in a state of wind-induced vibration. If the bridge is still in a state of wind-induced vibration, the damping plate 1 continues to swing until the wind-induced vibration of the bridge stops. If the wind-induced vibration of the bridge has stopped, the damping plate 1 stops swinging.

[0072] Between step S2 and step S1, there is also a step to determine whether the bridge is in a state of wind-induced vibration. The steps for determining whether the bridge is in a state of wind-induced vibration are as follows:

[0073] I. Obtain the wind-induced vibration displacement of the bridge and the corresponding time.

[0074] II. Perform Fourier transform on the vibration displacement of the bridge and the time corresponding to the displacement to obtain the frequency domain signal of the bridge vibration.

[0075] III. If the frequency domain signal of bridge vibration has a dominant frequency, it indicates that the bridge has wind-induced vibration, and the dominant frequency is taken as the wind vibration frequency f; if the frequency domain signal of bridge vibration does not have a dominant frequency, it indicates that the bridge does not have wind-induced vibration.

[0076] In step S1, the damping plate 1 is installed on both sides of the bottom surface of the main beam, and can also be installed on the outer edge of the two sides of the bridge tower perpendicular to the transverse direction of the bridge.

[0077] Example 2

[0078] like Figure 2 As shown, a system for mitigating wind-induced vibration in bridges includes:

[0079] The frequency acquisition module is used to acquire the wind vibration frequency f of the bridge;

[0080] The vibration damping module includes multiple vibration damping plates 1, which include type A plates 101 and type B plates 102. The vibration damping plates 1 are symmetrically arranged on both sides of the main beam or on the outer edges of the two sides of the bridge tower perpendicular to the transverse direction of the bridge, with the central axis of the main beam as the axis. The vibration damping plates 1 can swing about the normal line of the main beam. Type A plates 101 and type B plates 102 on the same side are staggered. The vibration damping plates 1 on both sides of the main beam or the bridge tower at the same transverse position are of the same type.

[0081] The control module receives the frequency f from the frequency acquisition module and controls the Class A board 101 according to the wind vibration frequency f. The B-type plate 102 oscillates at a frequency of (i+0.5)f, while the initial oscillation direction of the damping plate 1 on the same side is controlled to be the same, where i=0,1,2…n;

[0082] The frequency acquisition module signal is connected to the control module, and the control module signal is connected to the vibration reduction module.

[0083] The frequency acquisition module includes:

[0084] The vibration time history acquisition module is used to acquire the vibration displacement of the bridge and the corresponding time.

[0085] The signal conversion module is used to receive the signal transmitted by the vibration time history acquisition module, and perform Fourier transform on the vibration displacement of the bridge and the time corresponding to the displacement to obtain the frequency domain signal of the bridge vibration.

[0086] The judgment module receives the frequency domain signal transmitted by the signal conversion module and determines whether the bridge is in a wind-induced vibration state. If so, it extracts the dominant frequency of the frequency domain signal as the wind vibration frequency f and sends it to the control module; otherwise, it does not send a signal.

[0087] The vibration time history acquisition module's signal is connected to the signal conversion module, the signal conversion module's signal is connected to the judgment module, and the judgment module's signal is connected to the control module.

[0088] The vibration time history acquisition module includes displacement sensors installed at key locations on the main beam or bridge towers. The key locations on the main beam are the longitudinal 1 / 2, 1 / 4, and 3 / 4 positions; the key locations on the bridge towers include the top position. The signal conversion module includes intelligent control motors 2, which are divided into group A intelligent control motors 103 and group B intelligent control motors 104. Group A intelligent control motors 103 control the swaying of type A plate 101, and group B intelligent control motors 104 control the swaying of type B plate 102. Group A intelligent control motors 103 and group B intelligent control motors 104 are respectively installed at both ends of the main beam. Figure 6-7 As shown, intelligent control motors 2 are installed on both sides of the main beam. The arrangement of the vibration damping plates 1 is as follows. Figure 3 As shown, the working state of the damping plate 1 is as follows: Figure 4-5 As shown. Figure 8 This is a flow field diagram during the operation of this device, where the arrows indicate the wind direction. Figure 9 The diagram shows a comparison between using this device and not using it. In the diagram, the amplitude drops rapidly after wind speed 15 without control measures because the structure experiences vortex-induced vibration.

[0089] like Figure 6-7As shown, the damping plate 1 is connected to the rotating bearing 106 via the connecting member 105. The rotating bearing 106 is located inside the box girder or bridge tower, above each damping plate 1. The rotation of the rotating bearing 106 is transmitted to the damping plate 1 via the connecting member 105, causing the damping plate 1 to swing. The maximum swing angle of the damping plate 1 relative to the cross-section of the main girder or the cross-section of the bridge tower is ±30°, and the minimum swing angle is ±10°. Figure 10-11 As shown, in this embodiment, the connecting member 105 is disposed in the middle of the damping plate 1, and piezoelectric sheets 109 are disposed on both sides of the connecting member 105.

[0090] Group A intelligent control motor 103 and Group B intelligent control motor 104 are connected to the rotating bearing 106 via line 107 to transmit control signals, and are also connected to the displacement sensor 108 via line 107 to transmit bridge vibration displacement data.

[0091] The height h of the damping plate 1 is 0.15-0.3 times the height H of the main beam, and the length l of the damping plate 1 is 2-3 times h. Class A plates 101 and Class B plates 102 have the same dimensions and structure. The shape of the damping plate 1 can be a chamfered rectangle, an inverted trapezoid, or a narrow-flange I-beam, etc. In this embodiment, the damping plate 1 is made of a rigid material. Figure 3 As shown, the initial position of the damping plate 1 is parallel to the transverse direction of the bridge, does not block the wind, reduces the increased windward area caused by the addition of aerodynamic measures, reduces the overall wind load on the bridge, reduces lateral stability issues, lightens the bridge's self-weight, and further reduces costs. The center distance between two adjacent Class A plates 101 and Class B plates 102 is 1.5-4 times their own length l. Piezoelectric sheets 109 are provided on the surface of the damping plate 1. The damping plate 1 can also be made of a material with slightly lower stiffness, such as a flexible polymer composite material. When the fishtail damping plate 1 is in its original position, the damping plate 1 will oscillate periodically. The piezoelectric sheets 109 on the damping plate 1 have higher power generation efficiency.

[0092] The surface of the damping plate 1 is provided with non-continuous longitudinal stiffening ribs. The length of the longitudinal stiffening ribs is 2-3 times the height of the damping plate 1. The vertical stiffening ribs are not shown in the figure.

[0093] Example 3

[0094] like Figure 12-13 As shown, a system for mitigating wind-induced vibration in bridges is largely similar to Embodiment 2, except that the length of the damping plate 1 is reduced to 1-2 times its height, a connecting member is located at one end of the damping plate 1, and a larger cylinder 110 is provided outside the connecting member. The diameter of the cylinder 110 is 0.25-0.5 times the length of the damping plate 1. The flow field diagram of this device is shown below. Figure 14-16 As shown.

[0095] 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 method for mitigating wind-induced vibration in bridges, characterized in that, It includes the following steps: S1. Several damping plates (1) are symmetrically hinged on both sides of the main beam about the central axis of the main beam. The damping plates (1) can swing about the normal of the main beam. The damping plates (1) include Class A plates (101) and Class B plates (102). Class A plates (101) and Class B plates (102) are staggered on the same side of the bridge. The types of damping plates (1) on both sides of the main beam are corresponding. S2. Obtain the wind vibration frequency of the bridge. ; S3, control the damping plate (1) to start swinging, and the Class A plate (101) to... The B-type plate (102) oscillates at a frequency of [frequency missing]. The vibration damping plates (1) on different sides oscillate at the same frequency, with the initial oscillation directions being opposite. ; S4, the damping plate (1) begins to swing. After minutes, determine whether the bridge is in a state of wind-induced vibration. If the bridge is still in a state of wind-induced vibration, continue to control the swing of the damping plate (1) until the wind-induced vibration of the bridge stops; if the wind-induced vibration of the bridge has stopped, the damping plate (1) stops swinging. Between step S2 and step S1, there is also a step to determine whether the bridge is in a state of wind-induced vibration. The steps to determine whether the bridge is in a state of wind-induced vibration are as follows: I. Obtain the wind-induced vibration displacement of the bridge and the corresponding time. II. Perform Fourier transform on the vibration displacement of the bridge and the time corresponding to the displacement to obtain the frequency domain signal of the bridge vibration. III. If the frequency domain signal of bridge vibration has a dominant frequency, it indicates that the bridge is experiencing wind-induced vibration. This dominant frequency should be taken as the wind-induced vibration frequency. If the frequency domain signal of bridge vibration does not have a dominant frequency, it indicates that the bridge does not experience wind-induced vibration.

2. The method for mitigating wind-induced vibration in bridges according to claim 1, characterized in that, In step S1, the damping plate (1) can also be hinged and installed on the outer edge of the two sides of the bridge tower perpendicular to the transverse direction.

3. A system for mitigating wind-induced vibration in bridges, characterized in that, The method for mitigating wind-induced vibration of bridges as described in claim 2 comprises: The frequency acquisition module is used to acquire the wind vibration frequency of the bridge. ; The vibration reduction module includes multiple vibration reduction plates (1). The vibration reduction plates (1) include Class A plates (101) and Class B plates (102). The vibration reduction plates (1) are symmetrically arranged on both sides of the main beam or on the outer edges of the two sides of the bridge tower perpendicular to the transverse direction of the bridge, with the central axis of the main beam as the axis. The vibration reduction plates (1) can swing about the normal line of the main beam. Class A plates (101) and Class B plates (102) on the same side are staggered. The vibration reduction plates (1) on both sides of the main beam or the bridge tower at the same transverse position are of the same type. The control module is used to receive signals transmitted by the frequency acquisition module. And according to the wind vibration frequency Control Class A board (101) to The B-type plate (102) oscillates at a frequency of [frequency missing]. The frequency of the swing is controlled to be the same, and the initial swing direction of the damping plate (1) on the same side is controlled to be the same. ; The frequency acquisition module signal is connected to the control module, and the control module signal is connected to the vibration reduction module.

4. A system for mitigating wind-induced vibration in bridges according to claim 3, characterized in that, The frequency acquisition module includes: The vibration time history acquisition module is used to acquire the vibration displacement of the bridge and the corresponding time. The signal conversion module is used to receive the signal transmitted by the vibration time history acquisition module, and perform Fourier transform on the vibration displacement of the bridge and the time corresponding to the displacement to obtain the frequency domain signal of the bridge vibration. The judgment module receives the frequency domain signal transmitted by the signal conversion module and determines whether the bridge is in a state of wind-induced vibration. If so, it extracts the dominant frequency of the frequency domain signal as the wind vibration frequency. Send to the control module; otherwise, do not send a signal. The vibration time history acquisition module's signal is connected to the signal conversion module, the signal conversion module's signal is connected to the judgment module, and the judgment module's signal is connected to the control module.

5. A system for mitigating wind-induced vibration in bridges according to claim 3, characterized in that, The height of the damping plate (1) Main beam height Or 0.15-0.3 times the longitudinal dimension of the bridge tower, the length of the damping plate (1) itself. for The size and structure of Class A panels (101) and Class B panels (102) are 1-3 times that of Class B panels (102).

6. A system for mitigating wind-induced vibration in bridges according to claim 3, characterized in that, The center-to-center distance between two adjacent Class A panels (101) and Class B panels (102) is equal to their own length. The damping plate (1) is initially set along the cross-section of the main beam or the cross-section of the bridge tower, and the maximum swing angle of the damping plate (1) relative to the cross-section of the main beam or the cross-section of the bridge tower is 1.5-4 times that of the main beam. The minimum swing angle is .

7. A system for mitigating wind-induced vibration in bridges according to any one of claims 3-6, characterized in that, The surface of the damping plate (1) is provided with a piezoelectric sheet (109).

8. A system for mitigating wind-induced vibration in bridges according to any one of claims 3-6, characterized in that, The frequency acquisition module includes a displacement sensor (108), which is set at a key position of the main beam or a key position of the bridge tower. The signal conversion module includes an intelligent control motor (2), which includes a group A intelligent control motor (103) and a group B intelligent control motor (104). The group A intelligent control motor (103) is used to control the A-type plate (101), and the group B intelligent control motor (104) is used to control the B-type plate (102). The intelligent control motor (2) is located at the end of the main beam or at the ends of the two sides of the bridge tower perpendicular to the transverse direction of the bridge.

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