Movable bridge wind barrier and vortex vibration control mechanism analysis method

Abstract

The invention provides a movable bridge wind barrier and a vortex vibration control mechanism analysis method, and relates to the technical field of bridge equipment. The method comprises the steps that the wind barrier and at least one elastic piece are fixed; the at least one elastic piece is arranged between the fixed wind barrier and the bridge girder; the fixed wind barrier is composed of multiple layers of vertical handrails and multiple transverse rods, and the number of the vertical handrails and the number of the transverse rods are related to the ventilation rate of the bridge wind barrier; the rigidity of the elastic piece is determined based on a TMD classical optimal parameter formula. Various bridge wind barriers with different vortex-induced vibration suppression effects can be obtained by changing the rigidity and the position of the elastic piece and the number combination and the curvature of the vertical handrails and the transverse rods, the bridge wind barrier is suitable for various application scenes, mechanical and electronic multi-system coordination is not designed for the bridge wind barrier, and the implementation mode is simple.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of bridge equipment, and in particular to a movable bridge wind barrier and vortex vibration control mechanism analysis method. BACKGROUND

[0002] In recent years, vortex-induced vibration phenomena have been reported in many large-span bridges at home and abroad. Vortex vibration generally occurs at low wind speeds, although it does not destroy the structure instantaneously like flutter, but its vibration can last for a long time and repeatedly occur, leading to a decrease in driving comfort and passenger discomfort. Long-term repeated vibration can also exacerbate structural fatigue damage. Vortex-induced vibration has high sensitivity to the aerodynamic shape of the main girder, which determines the separation and reattachment of the main girder section airflow, the formation of the wake and vortex, and small changes in it can have a great impact on the vortex vibration characteristics, especially the wind barrier and other auxiliary facilities. Therefore, the existence of vortex-induced vibration phenomena has brought many hidden dangers to the normal operation of the bridge. In order to ensure the safe operation of the bridge, effective control measures must be taken to suppress vortex-induced vibration, which is of great significance to the safe operation and durability of the bridge.

[0003] In terms of vortex vibration control, the main strategies for suppressing vortex-induced vibration of bridges currently include: improving aerodynamic performance by optimizing the aerodynamic shape of the bridge section, increasing structural damping using mechanical means, and enhancing overall wind resistance by strengthening structural stiffness. Among them, fixed aerodynamic measures, due to their simple structure and the need for regular maintenance, have become the preferred solution for vortex vibration control of large-span box girder bridges, typical measures including wind barriers and guide vanes. Many scholars at home and abroad have studied the influence of wind barriers on bridge wind vibration control through numerical simulation or wind tunnel test methods, and found that vortex-induced vibration is sensitive to the details of the fixed wind barrier of the main girder section. The vortex vibration suppression ability of fixed wind barrier measures may have reached its limit, and there is limited space for further optimization, making it difficult to meet the wind resistance requirements in more complex wind environments. At the same time, active control relies on external energy sources, but active wind barrier measures involve multiple systems such as mechanics and electronics, and the technical implementation is complex, and is still in the experimental research stage, making it difficult to meet the practical application requirements in the short term. Therefore, it is necessary to develop a movable wind barrier measure between fixed wind barriers and active wind barriers, which has the advantages of both and is simple and practical, with good control effect. SUMMARY

[0004] The embodiments of the present application provide a movable bridge wind barrier and vortex vibration control mechanism analysis method to solve the problem that the current vortex vibration control method is difficult to meet the actual demand.

[0005] In a first aspect, the embodiments of the present application provide a movable bridge wind barrier, comprising: a fixed wind barrier and at least one elastic member; The at least one elastic member is arranged between the fixed wind barrier and the main girder of the bridge; And / or, at least one elastic member is arranged between two adjacent vertical bars in the fixed wind barrier; The fixed wind barrier is composed of multiple vertical bars and multiple horizontal bars, wherein the number of the vertical bars and the horizontal bars is related to the wind permeability of the bridge wind barrier; the stiffness of the elastic member is determined based on a classical optimal parameter formula of the TMD.

[0006] In a possible implementation, the at least one elastic member is arranged between the horizontal bars in the fixed wind barrier and the main girder of the bridge.

[0007] In a second aspect, an embodiment of the present application provides a vortex vibration control mechanism analysis method, which is used to determine the structural parameters of the movable bridge wind barrier provided in the first aspect, and the method comprises the following steps: calculating the main girder vortex vibration suppression response of the target bridge under the action of the wind load in different movable bridge wind barrier working conditions; analyzing the vortex vibration control mechanism in various movable bridge wind barrier working conditions according to the main girder vortex vibration suppression response; determining the structural parameters of the movable bridge wind barrier under the optimal vortex vibration control based on the vortex vibration control mechanism in various movable bridge wind barrier working conditions.

[0008] In a possible implementation, the main girder vortex vibration suppression response comprises the vertical vortex vibration displacement of the main girder and the wind barrier, the main girder surface pressure distribution data, the instantaneous vortex variation data, and the instantaneous streamline variation data; analyzing the vortex vibration control mechanism in various movable bridge wind barrier working conditions according to the main girder vortex vibration suppression response comprises the following steps: analyzing the mapping relationship between the motion characteristics of the main girder and the motion characteristics of the upstream and downstream wind barriers under the action of the wind load according to the vertical vortex vibration displacement data of the main girder and the wind barrier; analyzing the aerodynamic force characteristics of various movable bridge wind barrier working conditions under the action of the wind load according to the main girder surface pressure distribution data; analyzing the fluid motion characteristics of each movable bridge wind barrier working condition under the action of the wind load according to the instantaneous vortex variation data and the instantaneous streamline variation data, respectively; The vortex vibration control mechanism comprises the mapping relationship, the aerodynamic force characteristics, and the fluid motion characteristics.

[0009] In a possible implementation, analyzing the mapping relationship between the motion characteristics of the main girder and the motion characteristics of the upstream and downstream wind barriers under the action of the wind load according to the vertical vortex vibration displacement data of the main girder and the wind barrier comprises the following steps: For the vertical vortex vibration displacement data of the main girder and the wind barrier in any one movable bridge wind barrier working condition under the action of different preset wind speeds, the following steps are performed: fitting the vertical vortex vibration displacement of the main girder and the vertical vortex vibration displacement of the upstream and downstream wind barriers in the preset lock-in wind speed range by using a nonlinear function to obtain the coefficients of the vertical vortex vibration displacement of the upstream and downstream wind barriers; Based on the analysis of the vertical motion law of the windbreaks on both sides of the upstream and downstream and the contribution of the windbreaks to the vertical displacement of the main girder vortex vibration, a mapping relationship between the motion characteristics of the main girder and the motion characteristics of the upstream and downstream windbreaks under the action of wind load is obtained.

[0010] In a possible implementation, according to the main girder surface pressure distribution data, the aerodynamic force characteristics of each movable bridge windbreak working condition under the action of wind load are analyzed, including: For the main girder surface pressure distribution data of any one movable bridge windbreak working condition under the action of different preset wind speeds, the following steps are performed: The main girder surface pressure distribution data is analyzed to obtain the average pressure coefficient distribution and the fluctuating pressure coefficient distribution corresponding to the main girder surface pressure, and the influence law of various movable windbreaks on the aerodynamic force characteristics of the main girder; The average pressure coefficient distribution is used to represent the separation and reattachment of airflow on the box girder surface. The fluctuating pressure coefficient distribution is used to represent the instantaneous airflow disturbance intensity.

[0011] In a possible implementation, according to the instantaneous vorticity change data, the fluid motion characteristics of each movable bridge windbreak working condition under the action of wind load are analyzed, including: For the instantaneous vorticity change data of any one movable bridge windbreak working condition under the action of different preset wind speeds within a vibration period, the following steps are performed: According to the instantaneous vorticity change data, the change law of the vortex shedding mode corresponding to each time within the vibration period is obtained to identify the propagation path of the vortex flow; The propagation path of the vortex flow is used to analyze the inhibition mechanism and influencing factors of the movable windbreak on the vortex vibration.

[0012] In a possible implementation, according to the instantaneous flow line change data, the fluid motion characteristics of each movable bridge windbreak working condition under the action of wind load are analyzed, including: For the instantaneous flow line change data of any one movable bridge windbreak working condition under the action of different preset wind speeds within a vibration period, the following steps are performed: According to the instantaneous flow line change data, the distribution of the flow line around the main girder under different flow conditions within the vibration period is obtained; The distribution of the flow line under different flow conditions is used to reveal the airflow flow characteristics, wake evolution process, and adjust the airflow organization mode of the movable windbreak.

[0013] In a possible implementation, based on the vortex vibration control mechanism of various movable bridge windbreak working conditions, the structure parameters of the movable bridge windbreak under optimal vortex vibration control are determined, including: According to the vortex vibration control mechanism of each movable bridge wind barrier in each preset locking wind speed interval, the optimal vortex vibration suppression effect corresponding to each preset locking wind speed interval is determined. Based on the optimal vortex vibration suppression effect in each preset locking wind speed interval, the structure parameters of the movable bridge wind barrier corresponding to the optimal vortex vibration control under the current main beam form are determined.

[0014] In a possible implementation, based on the optimal vortex vibration suppression effect in each preset locking wind speed interval, the structure parameters of the movable bridge wind barrier corresponding to the optimal vortex vibration control under the current main beam form are determined, including: determining the vortex vibration control mechanism corresponding to the optimal vortex vibration suppression effect in each preset locking wind speed interval; comparing the vortex vibration control mechanism corresponding to the optimal vortex vibration suppression effect in each preset locking wind speed interval, to determine the vortex vibration control mechanism corresponding to the optimal vortex vibration suppression effect under the current main beam form; Based on the vortex vibration control mechanism corresponding to the optimal vortex vibration suppression effect under the current main beam form, the structure parameters of the movable bridge wind barrier corresponding to the optimal vortex vibration suppression effect under the current main beam form are determined.

[0015] In a possible implementation, based on the vortex vibration control mechanism corresponding to the optimal vortex vibration suppression effect under the current main beam form, the structure parameters of the movable bridge wind barrier corresponding to the optimal vortex vibration suppression effect under the current main beam form are determined, including: According to the vortex vibration control mechanism corresponding to the optimal vortex vibration suppression effect under the current main beam form, a plurality of groups of simulation structure parameters are generated; Calculate the simulation vortex vibration response data of the movable bridge wind barrier under the action of wind load corresponding to each group of simulation structure parameters; Collect the actual vortex vibration response data of the movable bridge wind barrier under the action of wind load under the current main beam form; Calculate the difference between the simulation vortex vibration response data and the actual vortex vibration response data corresponding to each group of simulation structure parameters; The simulation structure parameters corresponding to the simulation vortex vibration response data with the smallest difference are taken as the structure parameters of the movable bridge wind barrier corresponding to the optimal vortex vibration suppression effect under the current main beam form.

[0016] The embodiment of the present application provides a movable bridge wind barrier, which is composed of a fixed wind barrier and at least one elastic element, the elastic element can release energy when the wind barrier vibrates, generate a restoring force opposite to the vibration direction, and offset the effect of the vortex-induced force on the wind barrier. The fixed wind barrier is composed of multiple layers of vertical railings and multiple horizontal bars, by changing the number combination of the vertical railings and the horizontal bars, the wind permeability of the bridge wind barrier can be changed, and the curvature of the movable bridge wind barrier can be changed by the position of the multiple layers of vertical railings when the multiple layers of vertical railings are installed, the aerodynamic shape of the changed curvature can weaken the vortex-induced force, change the vibration response of the movable bridge wind barrier, and also change the rigidity of the movable bridge wind barrier. The elastic element cooperates with the fixed wind barrier, the fixed wind barrier weakens the source of the vortex-induced force, the elastic element transfers vibration energy through resonance energy absorption, double inhibits the vortex vibration of the main beam, and simultaneously reduces the movement amplitude of the main beam through the synchronous movement of the fixed wind barrier, so that the fatigue damage of the main beam structure is reduced. By changing the number of elastic elements, the number combination of vertical railings and horizontal bars, and the position of multiple layers of vertical railings when the multiple layers of vertical railings are installed, a plurality of movable bridge wind barriers with different high-order and low-order vortex vibration inhibition effects can be obtained, which are suitable for various application scenarios, and the movable bridge wind barrier does not design multiple systems such as mechanics and electronics to coordinate, and the implementation is simple. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is a split steel box girder structure system provided by the embodiment of the present application; Figure 2 is a comparison diagram of movable bridge wind barriers with different curvatures provided by the embodiment of the present application; Figure 3 is a structure schematic diagram of movable bridge wind barriers with different spring positions provided by the embodiment of the present application; Figures 4a-4d is a structure schematic diagram of movable bridge wind barriers with different curvatures provided by the embodiment of the present application; Figure 5 is an implementation flowchart of a vortex vibration control mechanism analysis method provided by the embodiment of the present application; Figure 6 is a simulation flowchart provided by the embodiment of the present application; Figure 7 is a mesh division diagram provided by the embodiment of the present application; Figure 8 is a comparison diagram of main beam vortex vibration vertical displacements under different measures provided by the embodiment of the present application; Figure 9 is a comparison diagram of main beam vortex vibration inhibition effects of movable bridge wind barriers under different working conditions provided by the embodiment of the present application; Figure 10 is a comparison diagram of main beam and wind barrier vertical movements provided by the embodiment of the present application; Figure 11 is a comparison diagram of main beam surface average pressure coefficients under different configurations of movable bridge wind barriers provided by the embodiment of the present application; Figures 12a-12b This is a streamline diagram of the main beam of a movable bridge under wind barriers of different stiffness provided in an embodiment of the present invention; Figures 13a-13b This is a vortex diagram of the main beam of a vertical and curved movable bridge windbreak provided in an embodiment of the present invention; Detailed Implementation The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0018] Figure 1 This is a structural system diagram of the split steel box girder provided in an embodiment of the present invention, as shown below. Figure 1 As shown, the bridge adopts a double-tower, single-span split steel box girder structure, which is a typical modern long-span bridge structure. For example, the main cable span arrangement of the bridge is 580m (side span) + 1756m (main span) + 630m (side span); the dimensions of the split box girder are 3.5 meters high, 0.6 meters at the center, and 40.1 meters wide. The vibration frequency of the bridge was studied through modal analysis. The first vertical bending frequency of the bridge is 2.238Hz, and the torsional frequency is 5.529Hz.

[0019] Figure 2 These are comparison diagrams of wind barriers on movable bridges with different curvatures provided in embodiments of the present invention; as shown. Figure 2 As shown, taking a split box girder bridge as an example, wind barriers are only installed on the windward and leeward sides, that is, the left and right figures in the diagram. ① is the wind barrier for a vertical bridge, ② is the wind barrier for a curved bridge, and ③ is the wind barrier for a strongly curved bridge.

[0020] Figure 3 This is a structural schematic diagram of a movable bridge windbreak with different spring positions provided in an embodiment of the present invention. For example... Figure 3 As shown, the movable bridge windbreak includes: Fixed windbreak 10 and at least one elastic element 20.

[0021] At least one elastic element 20 is provided between the fixed wind barrier 10 and the main bridge beam 30.

[0022] The fixed windbreak 10 consists of multiple layers of vertical railings 11 and multiple horizontal bars 12. The number of vertical railings 11 and horizontal bars 12 is related to the wind permeability of the bridge windbreak. The curvature of the bridge windbreak is determined based on the position of the multiple layers of vertical railings 11. The stiffness of the elastic element 20 is determined based on the TMD classical optimal parameter formula.

[0023] The movable bridge windbreak provided by the embodiment is composed of a fixed windbreak 10 and at least one elastic member 20, and is arranged on the upstream and downstream of a bridge girder 30, and is a movable windbreak, which is movable in that 1. under the action of the elastic member 20, the movable bridge windbreak can move together with the movement of the girder; 2. the number of the elastic member 20, the relative position between the elastic member 20 and the fixed windbreak 10, the rigidity of the elastic member 20, the number of vertical bars 11 and horizontal bars 12 in the fixed windbreak 10, and the position of the multiple layers of vertical bars 11 can be adjusted. By adjusting the above-mentioned related structures, movable bridge windbreaks with different windbreak rates, curvatures and rigidities can be obtained, and these different movable bridge windbreaks can produce different vortex vibration suppression effects under the action of the same wind load, so as to cope with various wind load scenes.

[0024] In the embodiment, the elastic member 20 can include a spring, a damper, an inerter and the like.

[0025] Optionally, the vortex vibration suppression effects of the movable bridge windbreaks arranged at different positions are different, and the at least one elastic member 20 is arranged between the horizontal bar 12 in the fixed windbreak and the bridge girder 30. And / or, the at least one elastic member 20 is arranged between two adjacent layers of vertical bars 11 in the fixed windbreak.

[0026] In the embodiment, the movable bridge windbreaks with different curvatures can adjust the airflow separation point, for example, a small curvature delays airflow separation, makes the vortex shedding irregular, and reduces the periodic excitation of vortex-induced forces; a large curvature causes airflow separation on the inside of the concave surface, generates new vortex flow, and offsets part of the damping effect. At the same time, the curvature also affects the structural rigidity, and the increase of the curvature increases the moment of inertia of the windbreak cross section, and the natural frequency is improved, away from the vortex-induced frequency, to avoid resonance.

[0027] Figures 4a-4d is a structural schematic view of the bridge windbreak with different curvatures provided by the embodiment, and the following describes the bridge windbreak with different curvatures based on the structural schematic view. Figures 4a-4d The arrangement of the fixed windbreak 10 in the bridge windbreak with different curvatures is described.

[0028] The curvature of the bridge windbreak is determined based on the position of the multiple layers of vertical bars 11, Figure 4a The vertical bridge windbreak is characterized in that the elastic member 20 is arranged between the fixed windbreak and the bridge girder, and the test view and the front view of the fixed windbreak are included in the vertical bridge windbreak, in the vertical bridge windbreak, for any one layer of vertical bars 11, if the layer of vertical bars 11 is connected in parallel with the corresponding upper layer of vertical bars 11, and the horizontal bars 12 of each layer are connected to each other, then the curvature of the bridge windbreak is 0.

[0029] Figure 4b The vertical bridge windbreak is characterized in that the elastic member 20 is arranged between the fixed windbreak 10 and the bridge girder 30.

[0030] Figure 4c The vertical column 11 of the movable bridge windbreak provided by the present application is not parallel to the corresponding upper vertical column 11, and the two are inclined at an angle in the vertical direction, forming a corresponding curvature, and each horizontal rod 12 of each layer is connected to each other.

[0031] 4d The movable bridge windbreak provided by the present application is not parallel to the corresponding upper vertical column 11, and the two are inclined at an angle in the vertical direction, forming a corresponding curvature, and each horizontal rod 12 of each layer is connected to each other.

[0032] For Figure 4c and Figure 4d The movable bridge windbreak provided by the present application is not parallel to the corresponding upper vertical column 11, and the two are inclined at an angle in the vertical direction, forming a corresponding curvature, and each horizontal rod 12 of each layer is connected to each other. Figure 4b Again, no further description is needed.

[0033] In summary, the movable bridge windbreak provided by the embodiment of the present application can be divided into vertical bridge windbreak, curved bridge windbreak and strong curved bridge windbreak based on its configuration. The movable bridge windbreak is composed of a fixed windbreak and at least one elastic element. The elastic element can release energy when the windbreak vibrates, generate a restoring force opposite to the vibration direction, and offset the effect of the vortex-induced force on the windbreak. The fixed windbreak is composed of multiple vertical columns and multiple horizontal rods. By changing the number of vertical columns and horizontal rods, the windbreak rate of the bridge windbreak can be changed. The curvature of the bridge windbreak can be changed by the position of the multiple vertical columns during installation. The aerodynamic shape of the changed curvature can weaken the vortex-induced force, change the vibration response of the bridge windbreak, and change the stiffness of the bridge windbreak. The elastic element cooperates with the fixed windbreak. The fixed windbreak weakens the source of the vortex-induced force, and the elastic element transfers vibration energy through resonance energy absorption. The double suppression of the vortex vibration of the main beam reduces the motion amplitude of the main beam through the synchronous motion of the fixed windbreak, thereby reducing the fatigue damage of the main beam structure. By changing the number of elastic elements, the number of vertical columns and horizontal rods, and the position of the multiple vertical columns during installation, a variety of movable bridge windbreaks with different high and low order vortex vibration suppression effects can be obtained, which are suitable for various application scenarios. The movable bridge windbreak does not design multiple systems such as mechanics and electronics to coordinate, and the implementation is simple.

[0034] Based on the movable bridge wind barrier provided in the embodiment, the scheme can realize the change of the fixed wind barrier, and the scheme is an active adaptive aerodynamic control method based on fluid-structure coupling, and the core feature is that vibration self-adaptive adjustment can be achieved according to wind, so that the optimal vibration suppression effect can be maintained under different wind environments. The advantages of the movable wind barrier scheme mainly include that the movable wind barrier scheme can move relative to the main beam vibration, and through the aerodynamic-structure coupling effect, the movable wind barrier scheme can always maintain the optimal vortex vibration suppression capacity under different working conditions. The movable wind barrier scheme combines the double advantages of mechanical vibration reduction and aerodynamic vibration suppression. In the movement process, the movable wind barrier scheme can dissipate part of the wind-induced vibration energy, thereby reducing the vibration response of the bridge and improving the safety and durability of the structure.

[0035] However, the control mechanism of the movable wind barrier scheme at the present stage is not clear enough, and only a small amount of exploratory work, such as the design of adjusting the posture of the wind barrier through the adjustment of the posture of the wind barrier to change the vortex vibration response, is adopted. Overall, such movable measures are still in the experimental verification stage, and lack of mature mechanism theory and application support. Therefore, the vortex vibration control mechanism analysis method is provided in the embodiment, which provides mature mechanism theory and application support for the movable wind barrier scheme, and on the other hand, determines the optimal structural parameters of the movable bridge wind barrier under different wind loads, so that the vortex vibration suppression effect is optimal.

[0036] Figure 5 The vortex vibration control mechanism analysis method provided in the embodiment is an implementation flowchart, as shown in Figure 5 The method can include the following steps. Step 110: Calculate the main beam vortex vibration suppression response of the target bridge under different movable bridge wind barrier working conditions under the action of wind load.

[0037] In the embodiment, the vortex vibration suppression data of the target bridge under different movable bridge wind barrier working conditions in the preset locking wind speed range, that is, the main beam vortex vibration suppression response, is first collected.

[0038] In the embodiment, the corresponding bridge model is constructed, the vortex-induced vibration of the main beam section in the flow field is numerically simulated, different types of movable bridge wind barriers are arranged on the left and right sides of the two box girders, the lower end of the movable bridge wind barrier is connected to the elastic part hook and connected to the main beam, so as to obtain the vortex vibration suppression response of the target bridge under different movable bridge wind barrier working conditions in different preset locking wind speed ranges, and obtain the optimal vortex vibration suppression scheme of the target bridge main beam form.

[0039] Step 120: According to the main beam vortex vibration suppression response, analyze the vortex vibration control mechanism under various movable bridge wind barrier working conditions.

[0040] In the embodiment, for each preset lock wind speed interval, the corresponding vortex vibration suppression data is analyzed to obtain the vortex vibration control mechanism of each movable bridge windbreak working condition under each preset wind speed interval.

[0041] Step 130: Based on the vortex vibration control mechanism of various movable bridge windbreak working conditions, the structural parameters of the movable bridge windbreak under the optimal vortex vibration control are determined.

[0042] In the embodiment, based on the vortex vibration control mechanism of each movable bridge windbreak working condition in each preset wind speed interval, the vortex vibration control mechanism under the current main beam form is determined, and the structural parameters of the movable bridge windbreak under the current main beam form are obtained by reverse deduction according to the vortex vibration control mechanism under the current main beam form.

[0043] In an optional embodiment, the main beam vortex vibration suppression response includes vertical vortex vibration displacement data of the main beam and the windbreak, main beam surface pressure distribution data, and instantaneous vortex variation data; and step 120 of analyzing the vortex vibration control mechanism of various movable bridge windbreak working conditions according to the main beam vortex vibration suppression response can include: Step 121: According to the vertical vortex vibration displacement data of the main beam and the windbreak, the mapping relationship between the motion characteristics of the main beam and the motion characteristics of the upstream and downstream windbreaks under the action of wind load is analyzed.

[0044] Step 122: According to the main beam surface pressure distribution data, the aerodynamic force characteristics of various movable bridge windbreak working conditions under each wind load are analyzed.

[0045] Step 123: According to the instantaneous vortex variation data and the instantaneous streamline variation data respectively, the fluid motion characteristics of each movable bridge windbreak working condition under the action of wind load are analyzed.

[0046] Among them, the vortex vibration control mechanism includes the mapping relationship, the aerodynamic force characteristics and the fluid motion characteristics.

[0047] Figure 6 is the simulation flowchart provided by the embodiment of the present application, based on Figure 6 , the embodiment utilizes the secondary development interface built in the fluid dynamics simulation software to embed the user-defined function therein. The basic parameters of the structural dynamic characteristics are determined, and the parameters such as mass, stiffness and damping coefficient are set. Then the corresponding function is used to calculate the aerodynamic force and moment borne by the object under the current flow field environment, so as to provide the basis for subsequent determination of the vortex vibration control mechanism. Figure 7 is the grid division diagram provided by the embodiment of the present application, which represents the simulation results of the double main beam bridge based on the grid division in the fluid dynamics simulation.

[0048] In the embodiment, fluid simulation software can be used to analyze the motion displacement of the main girder and the windbreak, the surface pressure distribution data of the main girder, the instantaneous vortex variation data, and the instantaneous streamline variation data of the main girder under the action of different movable bridge windbreaks of the same main girder form by using the dynamic mesh technology, analyze the correlation between the mapping relationship, the aerodynamic force characteristics and the fluid motion characteristics. In the embodiment, the mapping relationship between the vertical displacement of the main girder and the vertical displacement of the upstream and downstream windbreaks is obtained by using a nonlinear fitting function, the aerodynamic force characteristics are obtained based on the surface pressure distribution data of the flow field where the main girder is located, and the fluid motion characteristics are calculated by using the instantaneous vortex variation data and the instantaneous streamline variation data in the vibration period, so as to obtain two kinds of data for representing the aerodynamic force characteristics. The mapping relationship, the aerodynamic force characteristics and the fluid motion characteristics are analyzed as the vortex vibration control mechanism to provide mature mechanism theory and application support for the movable windbreak measures.

[0049] Figure 8 FIG. 1 is a comparison diagram of the vertical displacement of the main girder under different measures provided by the embodiment, which respectively shows the vertical displacement of the main girder under the conditions of no windbreak, that is, no measure, the condition of using a fixed windbreak to suppress vortex vibration, that is, a fixed measure, and the condition of using the movable bridge windbreak provided by the embodiment to suppress vortex vibration, that is, using the optimal movable windbreak measure. Based on the comparison diagram of the vertical displacement of the main girder under the three conditions, it can be known that the amplitude of the main girder under the condition of no measure is the largest, the amplitude of the main girder under the condition of the fixed measure is the second, and the amplitude of the main girder under the condition of the optimal movable windbreak measure is the smallest. Figure 8 It can be known from the diagram that the movable bridge windbreak provided by the embodiment has a good effect of suppressing vibration compared with other schemes.

[0050] In an optional embodiment, the step of analyzing the mapping relationship between the motion characteristics of the main girder and the motion characteristics of the upstream and downstream windbreaks under the action of wind load according to the vertical vortex vibration displacement data of the main girder and the windbreak in step 121 can include the following steps: For the vertical vortex vibration displacement data of the main girder and the windbreak under the action of any one movable bridge windbreak working condition of different preset wind speeds, the following steps are performed: The vertical vortex vibration displacement of the main girder and the vertical vortex vibration displacement of the upstream and downstream windbreaks in the preset locking wind speed interval are fitted by using a nonlinear function to obtain the coefficients of the vertical vortex vibration displacement of the upstream and downstream windbreaks.

[0051] The vertical motion law of the upstream and downstream windbreaks and the contribution of the vertical motion law to the suppression of the vertical displacement of the main girder are analyzed based on the coefficients to obtain the mapping relationship between the motion characteristics of the main girder and the motion characteristics of the upstream and downstream windbreaks under the action of wind load.

[0052] In the embodiment, the following formula can be selected as the three-dimensional nonlinear fitting function:

[0053] In the formula, x is the vertical displacement of the upstream wind barrier, y is the vertical displacement of the downstream wind barrier, z is the vertical displacement of the main beam, and the others are fitting coefficients.

[0054] The fitting result is as follows: It can be found from the coefficients of x and y that the wind barriers on both sides have a great influence on the vertical displacement of the vortex vibration of the main beam, and the upstream wind barrier has a greater contribution than the downstream wind barrier.

[0055] In an optional embodiment, in step 122, the aerodynamic force characteristics of each movable bridge wind barrier working condition under the action of wind load are analyzed according to the main beam surface pressure distribution data, including: For the main beam surface pressure distribution data of any one movable bridge wind barrier working condition under the action of different preset wind speeds, the following steps are performed: The main beam surface pressure distribution data is analyzed to obtain the average pressure coefficient distribution and the fluctuating pressure coefficient distribution corresponding to the surface pressure of the box girder in the main beam, and the influence law of various movable wind barriers on the aerodynamic force characteristics of the main beam surface.

[0056] The average pressure coefficient distribution is used to represent the separation and reattachment of airflow on the surface of the box girder. The fluctuating pressure coefficient distribution is used to represent the instantaneous airflow disturbance intensity.

[0057] Figure 9 is a comparison chart of the vortex vibration suppression effect of the bridge wind barrier of the main beam under different working conditions provided by the embodiment of the application, which shows the vortex vibration suppression rate of the main beam under different working condition combinations. The meanings of different working condition numbers are shown in Table 1.

[0058] Table 1 Comparison table of meanings of different working condition numbers

[0059] Figure 9 In the formula, working conditions 1, 2, 3, 4 and 5 in different wind permeability rates represent the wind permeability rates of 17.5, 34.17, 50.83, 67.5 and 83.33 respectively in the form of wind permeability, that is, the suppression rates corresponding to the cases where the form of composition is A, the spring stiffness is 60 and the position is M. Among them, the maximum amplitudes corresponding to each working condition are 0.0051, 0.0054, 0.0066, 0.01 and 0.017 respectively, and the suppression rates corresponding to each working condition are 94.57%, 94.26%, 92.98%, 89.36% and 81.91% respectively.

[0060] The working conditions 3, 6, 7 and 8 in different forms represent that the wind permeability is 50.83, the stiffness is 60, and the position is M, and the wind permeability forms are A, B, C and D respectively. The maximum amplitudes corresponding to the working conditions are 0.0066, 0.0091, 0.0065 and 0.0198 respectively, and the suppression rates corresponding to the working conditions are 92.98%, 90.32%, 93.09% and 78.94% respectively.

[0061] The working conditions 3, 9 and 10 in different stiffnesses represent that the wind permeability is 50.83, the wind permeability form is A, and the position is M, and the spring stiffnesses are 60, 48 and 70 respectively. The maximum amplitudes corresponding to the working conditions are 0.0066, 0.0159 and 0.0009 respectively, and the suppression rates corresponding to the working conditions are 92.98%, 83.09% and 99.04% respectively.

[0062] The working conditions 3, 11 and 12 in different positions represent that the wind permeability is 50.83, the wind permeability form is A, and the spring stiffness is 60, and the positions are M, U and L respectively. The maximum amplitudes corresponding to the working conditions are 0.0066, 0.0146 and 0.074 respectively, and the suppression rates corresponding to the working conditions are 92.98%, 84.47% and 21.28% respectively.

[0063] Figure 10 is a comparison diagram of the vertical displacement of the main beam and the wind barrier provided by the embodiment of the present application, which shows that the motion amplitudes of the main beam and the left and right wind barriers are not the same, the peak value of the motion of the main beam is the smallest, and the peak value of the right wind barrier is the largest. This is because the wind barrier and the main beam form a coupled system through the support, the main beam vibrates under the excitation of the flow field, and the spring drives the upstream and downstream wind barriers or is inversely affected by the vibration of the wind barriers. It can be clearly seen that the vertical displacement of the wind barrier significantly reduces the vertical displacement of the main beam.

[0064] Figure 11 is a comparison diagram of the average pressure coefficient of the main beam surface under different configurations of the movable bridge wind barrier provided by the embodiment of the present application. ①-④ in the figure are observation points on the upper surface of the double main beam bridge, which are points prone to sudden changes in the average pressure coefficient. Case 1 is a vertical wind barrier, case 4 is a curved wind barrier, and case 7 is a strong curved wind barrier. When vortex-induced vibration occurs, the flow field structure around the bridge will change significantly, and the average pressure coefficient can reflect the specific influence of this flow field change on the pressure distribution on the surface of the bridge. The average pressure coefficient reflects the attachment and shedding trend of the airflow on the surface of the bridge. Different colored lines represent different working conditions, which represent vertical wind barriers, curved wind barriers and strong curved wind barriers under the same stiffness. The midpoint of the split box girder bridge is taken as the origin, the left bridge is the negative half axis, and the right bridge is the positive half axis.

[0065] Based on Figures 9-11 the analysis of the comparative results, the embodiment analyzes the aerodynamic force characteristics of each movable bridge wind barrier working condition under the split box girder form according to the main girder surface pressure distribution data.

[0066] In the embodiment, the aerodynamic force characteristics of each movable bridge wind barrier working condition can be characterized by the average pressure coefficient distribution and the fluctuating pressure coefficient distribution.

[0067] Through the fluid mechanics software, the main girder surface pressure distribution data is analyzed to obtain the average pressure coefficient distribution and the fluctuating pressure coefficient distribution of the upper surface and the lower surface of the box girder in the main girder.

[0068] The average pressure coefficient is the spatial distribution of the average pressure coefficient of the main girder surface at different vertical distances, and the average pressure coefficient distribution represents the long-term average trend of the airflow, which can determine the vortex shedding position and strength, and the average value change trend of the average pressure coefficient can predict the separation and reattachment of the airflow on the model surface.

[0069] The fluctuating pressure coefficient is the spatial distribution of the fluctuating pressure coefficient of the main girder surface at different vertical distances, and the pressure coefficient root variance is used to represent the pressure fluctuation value of the model. The pressure fluctuation part provides the dynamic load of the model vibration, and the pressure coefficient root variance of the model surface can represent the strength of the pressure fluctuation. The fluctuating pressure coefficient distribution represents the instantaneous airflow disturbance intensity and is a direct reflection of the vortex-induced force source.

[0070] In an optional embodiment, the step 123 of analyzing the fluid motion characteristics of each movable bridge wind barrier working condition under the action of wind load according to the instantaneous vortex variation data can include: For the instantaneous vortex variation data of any one movable bridge wind barrier working condition under the action of different preset wind speeds within a vibration period, the following steps are performed: According to the transient vortex variation data, the change law of the vortex shedding mode corresponding to each time within the vibration period is obtained to identify the propagation path of the vortex flow; The propagation path of the vortex flow is used to analyze the suppression mechanism and influencing factors of the movable wind barrier on vortex vibration.

[0071] In an optional embodiment, the step 123 of analyzing the fluid motion characteristics of each movable bridge wind barrier working condition under the action of wind load according to the instantaneous flow line variation data can include: For the instantaneous flow line variation data of any one movable bridge wind barrier working condition under the action of different preset wind speeds within a cycle, the following steps are performed: According to the instantaneous flow line variation data, the distribution of the flow line around the main girder under different flow conditions within the vibration period is obtained; Wherein, the distribution of flow lines under different flow conditions is used to reveal the airflow flow characteristics, the wake evolution process and to adjust the airflow organization mode in the movable wind barrier.

[0072] In this embodiment, the fluid motion characteristics can be characterized by the instantaneous vorticity diagram and the instantaneous flow line diagram.

[0073] The fluid simulation software is used to analyze the instantaneous vorticity change data, and the maximum vortex vibration amplitude of the target bridge girder in the preset wind speed interval is obtained. The maximum vortex vibration amplitude is also the maximum value in the vortex vibration displacement response of the girder.

[0074] Similarly, assuming that there are 8 different times in a vibration period, the fluid simulation software is used to analyze the flow field evolution of the flow line change data, and 8 flow line diagrams around the girder and the wind barrier at different times in a vibration period are obtained. The vortex structure is identified by the flow lines, and the flow separation and reattachment zones are displayed. When the overall flow field becomes uneven, the vortex flow is faster, the size is larger, the strength is higher, and the risk of vortex-induced vibration is more likely to increase. Accordingly, the instantaneous vorticity diagram around the girder and the wind barrier at 8 different times in a vibration period is obtained by analyzing the flow line change data. The instantaneous vorticity diagram is analyzed to determine the alternating shedding, movement and reattachment rules of the vortex shedding pattern around the girder. It is also determined whether there is a large-scale vortex structure in the vortex distribution. When the vortex structure size becomes smaller and the strength decreases, it indicates that the current movable bridge wind barrier has played a significant role in reducing the amplitude.

[0075] In an optional embodiment, the step 130 of determining the structure parameters of the movable bridge wind barrier under the optimal vortex vibration control based on the vortex vibration control mechanism of each working condition of the movable bridge wind barrier can include: Step 131: According to the vortex vibration control mechanism of each working condition of the movable bridge wind barrier in the preset locking wind speed interval, the optimal vortex vibration suppression effect corresponding to each preset locking wind speed interval is determined.

[0076] Step 132: Based on the optimal vortex vibration suppression effect in each preset locking wind speed interval, the structure parameters of the movable bridge wind barrier corresponding to the optimal vortex vibration control under the current girder form are determined.

[0077] In this embodiment, for any type of bridge girder form, the vortex vibration control mechanism of all working conditions of the movable bridge wind barrier under the girder form is determined. For any working condition of the movable bridge wind barrier, the maximum vortex vibration amplitude with or without the measure is calculated by using the pre-determined weight and the corresponding vortex vibration suppression index value. The optimal vortex vibration suppression index value under the girder form is selected, and the vortex vibration control mechanism corresponding to the optimal vortex vibration suppression index value is taken as the optimal vortex vibration suppression effect under the current girder form.

[0078] According to the optimal vortex suppression effect of each main beam form, the structure parameters of the bridge windbreak under the current main beam form are determined by reverse deduction.

[0079] In an optional embodiment, the determination of the structure parameters of the movable bridge windbreak corresponding to the optimal vortex suppression effect under the current main beam form based on the optimal vortex suppression effect in each preset locked wind speed interval in step 132 can include: Determining the vortex suppression mechanism corresponding to the optimal vortex suppression effect in each preset locked wind speed interval.

[0080] Comparing the vortex suppression mechanisms corresponding to the optimal vortex suppression effect in each preset locked wind speed interval, the vortex suppression mechanism corresponding to the optimal vortex suppression effect under the current main beam form is determined.

[0081] Based on the vortex suppression mechanism corresponding to the optimal vortex suppression effect under the current main beam form, the structure parameters of the movable bridge windbreak corresponding to the optimal vortex suppression effect under the current main beam form are determined.

[0082] In an optional embodiment, the determination of the structure parameters of the movable bridge windbreak corresponding to the optimal vortex suppression effect under the current main beam form based on the vortex suppression mechanism corresponding to the optimal vortex suppression effect under the current main beam form can include: According to the vortex suppression mechanism corresponding to the optimal vortex suppression effect under the current main beam form, a plurality of groups of simulation structure parameters are generated.

[0083] The simulation response data of the movable bridge windbreak under the action of wind load corresponding to each group of simulation structure parameters are calculated.

[0084] The actual response data of the movable bridge windbreak under the action of wind load under the current main beam form are collected.

[0085] The difference between the simulation response data corresponding to each group of simulation structure parameters and the actual response data is calculated.

[0086] The simulation structure parameters corresponding to the simulation response data with the smallest difference are taken as the structure parameters of the movable bridge windbreak corresponding to the optimal vortex suppression effect under the current main beam form.

[0087] Figures 12a-12b is the main beam streamline diagram of the movable bridge windbreak with different stiffness provided by the embodiment of the present application; Figures 13a-13b is the main beam vortex diagram of the vertical and curved bridge windbreak, which is an effect diagram obtained by simulation analysis based on the movable bridge windbreak provided by the embodiment of the present application.

[0088] Specifically, Figures 12a-12bFig. 4 is a vortex diagram of the vertical windbreak and the strong curved windbreak at the same moment (4 / 8T) in a cycle, the main vortexes are arranged in multiple columns in the downstream direction, and the whole shows a steady advancing trend. Although there is slight mutual interference between the vortexes, there is no severe merging or destructive reconstruction. The wake structure is compact, the streamline swing is significantly reduced, the vortexes in the slot area tend to be stable, and show the characteristics of independent distribution and regularity. Figures 13a-13b Fig. 4 is a vortex diagram of the vertical windbreak and the strong curved windbreak at the same moment (4 / 8T) in a cycle, the main vortexes are arranged in multiple columns in the downstream direction, and the whole shows a steady advancing trend. Although there is slight mutual interference between the vortexes, there is no severe merging or destructive reconstruction. The wake structure is compact, the streamline swing is significantly reduced, the vortexes in the slot area tend to be stable, and show the characteristics of independent distribution and regularity.

[0089] Based on the above analysis, in the present embodiment, the optimal vortex vibration control mechanism corresponding to the current main beam form is taken as a constraint condition to generate multiple groups of simulated structure parameters. The constraint conditions include: The motion expansion equation of the windbreak structure is:

[0090]

[0091] In the formula, is the mass of the windbreak structure; is the mass of the tuned mass damper; , , are the acceleration, velocity and displacement of the windbreak structure, respectively; , are the damping and structural stiffness of the windbreak structure, respectively; , are the damping coefficient and stiffness coefficient of the tuned mass damper (TMD), respectively; is the wind load vector, which is the force of the wind acting on the windbreak; is the TMD control force vector, which is generated by the TMD and used to suppress the vibration of the windbreak; , are the displacement and velocity vectors of the TMD relative to the windbreak.

[0092] Based on the classical optimal parameter formula of the TMD, the optimal tuning frequency and the best damping ratio are:

[0093]

[0094]

[0095]

[0096] wherein, is the optimal frequency ratio; is the intermediate variable; is the optimal damping ratio; is the natural frequency of the structure, i.e. the fundamental frequency of the bridge.

[0097] Under the above constraints, the probability distribution of these random variables can be determined by using the maximum entropy principle, assuming that they are subject to Gamma distribution, and a large number of samples conforming to the probability distribution of the wind barrier stiffness and damping are generated by using the Monte Carlo simulation method, i.e. a plurality of groups of simulated structure parameters are generated.

[0098] For each group of simulated structure parameters, i.e. each sample, the simulated response data of the wind barrier corresponding thereto under the action of wind load, such as displacement, acceleration and the like, are calculated by substituting the simulated structure parameters into the dynamic model.

[0099] The actual response data of the bridge wind barrier under the action of wind load in the current main beam form are obtained by direct measurement.

[0100] For any one group of simulated structure parameters, the difference between the simulated response data and the actual response data corresponding thereto is calculated by the following formula:

[0101] wherein, represents the difference between the simulated response data and the actual response data under the condition that the wind barrier porosity is and the damping is represents the number of samples; represents the maximum simulated response data obtained by simulation under the given wind barrier porosity and damping in the th sample; represents the actual response data corresponding to the maximum simulated response data.

[0102] The simulated structure parameters corresponding to the simulated response data with the smallest difference are taken as the structure parameters of the bridge wind barrier in the current main beam form by the above formula, wherein the structure parameters can include the number, position, stiffness of the elastic members, the curvature of the fixed wind barrier, the number and arrangement position of the vertical rail and crossbar and the like.

[0103] In summary, the method provided by the embodiment not only provides a reference mechanism for the movable aerodynamic measure, but also can determine the design parameters of the bridge wind barrier.

[0104] ​It should be understood that the size of the serial number of each step in the above embodiments does not mean the order of execution, and the execution order of each process should be determined according to its function and inherent logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0105] In the above embodiments, the description of each embodiment has its own focus, and the parts not described or recorded in a certain embodiment can refer to the relevant description of other embodiments. If there is no special description and logical conflict, the terms and / or descriptions between different embodiments are consistent and can be mutually referred to, and the technical features in different embodiments can be combined to form new embodiments according to their inherent logical relationship.

[0106] The above-described embodiments are only used to illustrate the technical solutions of the present application, rather than limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that the technical solutions recorded in the foregoing embodiments can still be modified, or some technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application.

Claims

1. A movable bridge windbreak, characterized in that, include: A fixed windbreak and at least one elastic element; At least one elastic element is disposed between the fixed windbreak and the main beam of the bridge; And / or, the at least one elastic element is disposed between two adjacent vertical railings in the fixed windbreak; The fixed windbreak consists of multiple layers of vertical railings and multiple horizontal bars, wherein the number of vertical railings and horizontal bars is related to the wind permeability of the bridge windbreak; the stiffness of the elastic element is determined based on the TMD classical optimal parameter formula.

2. A method for analyzing the control mechanism of vortex vibration, characterized in that, The method is used to determine the structural parameters of the movable bridge windbreak as described in claim 1, and the method includes: Calculate the vortex-induced vibration suppression response of the main girder of the target bridge under different wind barrier conditions for movable bridges under wind load; Based on the main beam vortex-induced vibration suppression response, the vortex-induced vibration control mechanism under various wind barrier conditions of movable bridges is analyzed. Based on the vortex-induced vibration control mechanism under various working conditions of movable bridge wind barriers, the structural parameters of movable bridge wind barriers under optimal vortex-induced vibration control are determined.

3. The vortex vibration control mechanism analysis method according to claim 2, characterized in that, The main girder vortex-induced vibration suppression response includes vertical vortex-induced vibration displacement data of the main girder and wind barrier, pressure distribution data on the main girder surface, instantaneous vortex change data, and instantaneous streamline change data; the analysis of the vortex-induced vibration control mechanism under various movable bridge wind barrier conditions based on the main girder vortex-induced vibration suppression response includes: Based on the vertical vortex-induced vibration displacement data of the main beam and the windbreak, the mapping relationship between the motion characteristics of the main beam and the motion characteristics of the upstream and downstream windbreaks under wind load is analyzed. Based on the pressure distribution data on the main beam surface, the aerodynamic characteristics of various movable bridge wind barrier conditions under wind load are analyzed. Based on the instantaneous vorticity change data and the instantaneous streamline change data, the fluid motion characteristics of each movable bridge wind barrier under wind load are analyzed. The vortex vibration control mechanism includes mapping relationships, aerodynamic characteristics, and fluid motion features.

4. The vortex vibration control mechanism analysis method according to claim 3, characterized in that, The step of analyzing the mapping relationship between the motion characteristics of the main beam and the motion characteristics of the upstream and downstream wind barriers under wind load, based on the vertical vortex-induced displacement data of the main beam and the wind barriers, includes: For any movable bridge wind barrier working condition under different preset wind speeds, the following steps are performed: The vertical vortex-induced vibration displacement of the main beam and the vertical vortex-induced vibration displacement of the upstream and downstream wind barriers within the preset locked wind speed range are fitted using a nonlinear function to obtain the coefficients of the vertical vortex-induced vibration displacement of the upstream and downstream wind barriers. Based on the coefficient analysis, the vertical motion law of the upstream and downstream wind barriers and their contribution to the suppression of the vertical displacement of the main beam under vortex-induced vibration are obtained, so as to obtain the mapping relationship between the motion characteristics of the main beam and the motion characteristics of the upstream and downstream wind barriers under wind load.

5. The vortex vibration control mechanism analysis method according to claim 3, characterized in that, The analysis of the aerodynamic characteristics of various movable bridge windbreak conditions under wind load, based on the pressure distribution data on the main beam surface, includes: For the pressure distribution data on the main beam surface of any movable bridge under wind barrier conditions with different preset wind speeds, perform the following steps: The pressure distribution data on the surface of the main beam was analyzed to obtain the average pressure coefficient distribution and pulsating pressure coefficient distribution corresponding to the surface pressure of the box girder in the main beam, as well as the influence law of various movable wind barriers on the aerodynamic characteristics of the main beam surface. The average pressure coefficient distribution is used to characterize the separation and reattachment of airflow on the surface of the box girder; The pulsating pressure coefficient distribution is used to characterize the intensity of instantaneous airflow disturbance.

6. The vortex vibration control mechanism analysis method according to claim 3, characterized in that, The analysis of fluid motion characteristics of various movable bridge windbreak conditions under wind load based on the instantaneous vorticity change data includes: For the instantaneous vorticity change data of any movable bridge wind barrier under different preset wind speeds within one vibration cycle, perform the following steps: Based on the transient vorticity change data, the variation law of the vortex shedding mode at each moment within the vibration cycle is obtained, so as to identify the propagation path of the vortex. The propagation path of the eddy current is used to analyze the suppression mechanism and influencing factors of eddy vibration by the movable wind barrier.

7. The vortex vibration control mechanism analysis method according to claim 3, characterized in that, The analysis of fluid motion characteristics of various movable bridge wind barriers under wind load based on the instantaneous streamline change data includes: For the instantaneous streamline change data of any movable bridge wind barrier under different preset wind speeds within one vibration cycle, perform the following steps: The flow field evolution is performed based on the instantaneous streamline change data to obtain the distribution of streamlines around the main beam under different flow conditions within the vibration cycle; The distribution of streamlines under different flow conditions is used to reveal the characteristics of airflow, the evolution of the wake, and to adjust the airflow organization by the movable wind barrier.

8. The vortex vibration control mechanism analysis method according to claim 2, characterized in that, The vortex-induced vibration control mechanism based on various movable bridge wind barrier conditions determines the structural parameters of the movable bridge wind barrier under optimal vortex-induced vibration control, including: Based on the vortex-induced vibration control mechanism of each movable bridge wind barrier working condition within the preset locked wind speed range, the optimal vortex-induced vibration suppression effect corresponding to each preset locked wind speed range is determined. Based on the optimal vortex-induced vibration suppression effect within each preset locked wind speed range, the structural parameters of the movable bridge wind barrier corresponding to the optimal vortex-induced vibration control under the current main beam configuration are determined.

9. The vortex vibration control mechanism analysis method according to claim 8, characterized in that, The structural parameters of the movable bridge wind barrier corresponding to the optimal vortex-induced vibration suppression effect under the current main girder configuration are determined based on the optimal vortex-induced vibration suppression effect within each preset locked wind speed range, including: Determine the vortex-vibration control mechanism corresponding to the optimal vortex-vibration suppression effect within each preset locked wind speed range; By comparing the vortex-vibration control mechanisms corresponding to the optimal vortex-vibration suppression effect within each preset locked wind speed range, the vortex-vibration control mechanism corresponding to the optimal vortex-vibration suppression effect under the current main beam configuration is determined. Based on the vortex-induced vibration suppression effect under the current main girder configuration and the corresponding vortex-induced vibration control mechanism, the structural parameters of the movable bridge windbreak corresponding to the optimal vortex-induced vibration control under the current main girder configuration are determined.

10. The vortex vibration control mechanism analysis method according to claim 9, characterized in that, The vortex-induced vibration control mechanism, based on the optimal vortex-induced vibration suppression effect under the current main girder configuration, determines the structural parameters of the movable bridge windbreak corresponding to the optimal vortex-induced vibration control under the current main girder configuration, including: Based on the vortex-induced vibration control mechanism corresponding to the optimal vortex-induced vibration suppression effect under the current main beam configuration, multiple sets of simulated structural parameters are generated. Calculate the simulated response data of the movable bridge wind barrier under wind load for each set of simulated structural parameters; Collect actual response data of the wind barrier of the movable bridge with the current main girder configuration under wind load; Calculate the difference between the simulated response data and the actual response data corresponding to each set of simulated structural parameters; The simulated structural parameters corresponding to the simulated response data with the smallest difference are taken as the structural parameters of the movable bridge windbreak corresponding to the optimal vortex-induced vibration control under the current main beam form.

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