A bridge wind tunnel test device and test method

Abstract

The present invention relates to the technical field of wind tunnel testing, and discloses a bridge wind tunnel testing device and testing method, wherein the device comprises a base, a lifting mechanism, a support frame, a swing mechanism and a bridge segment model; the base comprises a pedestal and a mounting slot; the lifting mechanism is arranged in the mounting slot, and its output end is connected to the first end of the support frame, and is used to drive the support frame to perform reciprocating linear motion in the vertical direction; the second end of the support frame is provided with a swing mechanism, and the bridge segment model is rotatably arranged on the support frame through the swing mechanism. The present invention provides vertical displacement and vibration through the lifting mechanism, and at the same time, the swing mechanism provides periodic rotation and swing around the axial direction of the bridge segment model, thereby realizing three-degree-of-freedom motion simulation of the bridge model, and being able to reproduce the bridge vibration scene more realistically and accurately, especially being able to reproduce the real bridge vortex-induced vibration and flutter scenes, thereby improving the simulation and accuracy of the bridge wind-induced vibration scene simulation.

Description

Technical Field

[0001] The invention relates to the technical field of wind tunnel testing, and in particular to a bridge wind tunnel testing device and a testing method. Background Art

[0002] The vehicle-bridge system wind tunnel test is developed by adding a train aerodynamic test device on the basis of the bridge wind tunnel test. The experimental model needs to accurately reproduce the wind-induced vibration response of the bridge and the train at the same time. Due to many interference factors, the existing vehicle-bridge system wind tunnel test models at this stage face severe challenges in terms of bridge multi-modal fluid-solid coupling and vehicle-bridge wind-induced vibration simulation.

[0003] The force measurement method of the traditional wind tunnel test is difficult to accurately measure the overall aerodynamic load of the model under test. The six-dimensional force sensor can measure the overall aerodynamic load of the object under test more accurately, and is often used to measure the aerodynamic load of structures with complex aerodynamic shapes. However, affected by factors such as the rotation of the wind tunnel motor, the interaction between the wind and the tunnel body and diversion facilities, and the fluid-solid coupling between the wind and the object under test, the instantaneous measurement results of the dynamic balance mainly include interference caused by aerodynamic loads, inertial loads, and random vibrations of the environment. The inertial load value is often several times the aerodynamic load, and the inertial load and the aerodynamic load are often coupled together at the dominant frequency. Therefore, it is extremely difficult to accurately extract the instantaneous aerodynamic load of the object under test from the dynamic balance measurement results. On the other hand, for complex fluid-solid coupling vibrations with multiple degrees of freedom, there may be aerodynamic coupling between the degrees of freedom, and it is necessary to synchronously measure the acceleration and displacement on multiple degrees of freedom, especially torsional vibrations.

[0004] In summary, at present, the wind tunnel test technology of the vehicle-bridge system is still in the exploratory stage. There is an urgent need for a bridge wind tunnel test device that can realize multi-degree-of-freedom vibration of the bridge segment model and more accurately simulate the vibration of the actual bridge in the actual wind field, so as to accurately obtain the aerodynamic characteristics of the large-span railway bridge-train system. Summary of the invention

[0005] The object of the present invention is to provide a bridge wind tunnel test device, and its specific technical scheme is as follows:

[0006] A bridge wind tunnel test device comprises a base, a lifting mechanism, a support frame, a swing mechanism and a bridge segment model;

[0007] The base comprises a pedestal and a mounting groove, wherein the mounting groove is arranged on the pedestal;

[0008] The lifting mechanism is arranged in the installation groove, and its output end is connected to the first end of the support frame, and is used to drive the support frame to perform reciprocating linear motion in the vertical direction;

[0009] The second end of the support frame is provided with a swing mechanism, and the bridge segment model is rotatably arranged on the second end of the support frame through the swing mechanism.

[0010] Preferably, the lifting mechanism comprises a linear motor and a sliding plate;

[0011] The linear motor is fixedly arranged in the mounting groove, and the sliding plate is fixedly connected to the output end of the linear motor;

[0012] The mounting groove is arranged along the vertical direction, and is used for the sliding plate to perform reciprocating linear motion in the mounting groove along the vertical direction;

[0013] The sliding plate is also connected to the fixing plate at the first end of the supporting frame.

[0014] Preferably, the side surface of the support frame is a triangular structure, and the swing mechanism is provided at both corners of the second end of the support frame; and the two groups of the swing mechanism are located on the same vertical line.

[0015] Preferably, the swing mechanism comprises a swing motor, a cylindrical sleeve and a bearing;

[0016] The bearing and the swing motor are arranged relatively on the support frame, and the columnar sleeve is arranged in the bearing; one end of the bridge segment model is connected to the columnar sleeve, and the other end is transmission-connected to the swing motor.

[0017] Preferably, a first type of through rod is arranged on the bridge segment model along its length direction, one end of the first type of through rod is connected to the columnar sleeve through a left connecting plate, and the other end is connected to the output flange of the swing motor through a right connecting plate.

[0018] Preferably, the columnar sleeve comprises a sleeve body and a sleeve connecting plate, the sleeve body is fixedly connected to the sleeve connecting plate; the left connecting plate is connected to the sleeve connecting plate, and the sleeve body is arranged in a bearing.

[0019] Preferably, a plurality of groups of second-type through rods are also arranged throughout the length direction of the skeleton of the bridge segment model;

[0020] An upper force plate is also provided on the first type through rod, and multiple groups of the second type through rods are connected via a lower force plate; the upper force plate and the lower force plate are also connected via a force sensor.

[0021] Preferably, partitions are arranged at intervals in the skeleton; the skeleton of the bridge segment model is made of carbon fiber material, and the cross section of the skeleton is a triangular structure.

[0022] Preferably, a plurality of groups of reinforcing diagonal braces are further provided on the side of the installation groove, one end of the reinforcing diagonal brace is fixedly connected to the base, and the other end of the reinforcing diagonal brace is fixedly connected to the side of the installation groove.

[0023] The application of the technical solution of the present invention has the following beneficial effects:

[0024] A bridge wind tunnel test device includes a base, a lifting mechanism, a support frame, a swing mechanism and a bridge segment model; the base includes a pedestal and a mounting slot, and the mounting slot is arranged on the base; the lifting mechanism is arranged in the mounting slot, and its output end is connected to the first end of the support frame, and is used to drive the support frame to perform reciprocating linear motion in the vertical direction; the second end of the support frame is provided with a swing mechanism, and the bridge segment model is rotatably arranged on the second end of the support frame through the swing mechanism. The present invention provides displacement and vibration of the model in the vertical direction through the lifting mechanism, and the swing mechanism can provide periodic rotation and swing around the axial direction of the bridge segment model while the bridge model obtains up and down displacement and vibration, thereby realizing the three-degree-of-freedom motion simulation of the bridge model, and can reproduce the bridge vibration scene more realistically and accurately, especially can reproduce the real bridge vortex-induced vibration and flutter scenes, and improve the simulation and accuracy of the bridge wind-induced vibration scene simulation.

[0025] The present invention also provides a bridge wind tunnel test method, which uses the above-mentioned bridge wind tunnel test device to perform a test, comprising the following steps:

[0026] Step 1: Debug the bridge wind tunnel test device to keep the mass, aerodynamic shape and test environment of the two groups of bridge segment models consistent, and establish the test model and compensation model of the bridge segment model;

[0027] Step 2: According to the actuation requirements, the external control device inputs a driving signal to the linear motor and the swing motor to realize the multi-modal coupling vibration of three degrees of freedom of the test model and the compensation model;

[0028] Step 3: Collect the load data collected by the six-dimensional force sensors of the test model and the compensation model during the multi-modal coupling vibration process, and at the same time record and save the actuation data of the linear motor and the swing motor in real time through the control system;

[0029] Step 4: Process the data collected by the compensation model and the test model to obtain the model aerodynamic force without environmental and inertial interference. Specifically:

[0030] The displacement generated by the vibration of the compensation model is , which includes Axis direction and The degree of freedom of motion in the direction of The axis direction is the vertical direction of the linear motor. The direction of freedom is the direction of rotation of the swing motor;

[0031] according to Obtain the additional self-excited force generated by the compensation model that is not caused by wind , while compensating for the fact that the model is also subject to gravity and environmental vibration , It is expressed as follows:

[0032] ;

[0033] in, is the non-wind-induced additional mass coefficient, is the non-wind-induced additional damping coefficient, To compensate for model quality;

[0034] During the test, the compensation model will be placed in place and the balance will be cleared to remove the gravity of the compensation model. The dynamic balance test result of the compensation model is It is expressed as:

[0035] 1);

[0036] Test the displacement of the model caused by vibration Displacement generated by the compensation model Exactly the same, compared to the compensation model, the test model is still in the wind tunnel test section and is subjected to wind loads ;

[0037] Dynamic balance test results of the test model It is expressed as:

[0038] 2);

[0039] in, To test the quality of the model, To test the model's environmental vibration, The non-wind-induced additional self-excited forces generated for the test model;

[0040] Since the test environment, model mass and aerodynamic shape of the compensation model and the test model are the same, ;

[0041] From equation 2) and equation 1), the model aerodynamic force is obtained by eliminating the environmental and inertial interference in real time.

[0042] In addition to the above-described purposes, features and advantages, the present invention has other purposes, features and advantages. The present invention will be further described in detail with reference to the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0044] Figure 1 It is a structural schematic diagram of a bridge wind tunnel test device provided by the present invention;

[0045] Figure 2 for Figure 1 Structural diagram of the lifting mechanism;

[0046] Figure 3 This is a schematic diagram of the structure after the support frame, bearings and swing motor mounting plate are assembled;

[0047] Figure 4 for Figure 1 Schematic diagram of the structure after the middle swing mechanism and bridge segment model are assembled;

[0048] Figure 5 for Figure 4 Schematic diagram of the structure of the middle and lower force plates.

[0049] In the figure: 1. base, 1.1. pedestal, 1.2. mounting groove; 2. lifting mechanism, 2.1. linear motor, 2.2. sliding plate; 3. support frame, 3.1. fixed plate; 4. swing mechanism, 4.1. swing motor, 4.2. cylindrical sleeve, 4.21. sleeve body, 4.22. sleeve connecting plate, 4.3. bearing, 4.4. swing motor mounting plate; 5. bridge segment model, 5.1. skeleton, 5.2. first type through rod, 5.3. left connecting plate, 5.4. right connecting plate, 5.5. second type through rod, 5.6. upper force plate, 5.7. lower force plate, 5.8. partition; 6. strengthening diagonal brace. DETAILED DESCRIPTION

[0050] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0051] refer to Figure 1A bridge wind tunnel test device includes a base 1, a lifting mechanism 2, a support frame 3, a swing mechanism 4 and a bridge segment model 5; the base 1 includes a base 1.1 and a mounting groove 1.2, and the mounting groove 1.2 is arranged on the base 1.1; wherein the base is placed on the mounting plane, mainly to provide stability for the test device during operation and prevent tipping; the mounting groove extends vertically above the base to provide an installation position for the linear motor. The lifting mechanism 2 is arranged in the mounting groove 1.2, and its output end is connected to the first end of the support frame 3, and is used to drive the support frame 3 to perform reciprocating linear motion in the vertical direction; the support frame is a rigid support frame. The second end of the support frame 3 is provided with a swing mechanism 4, and the bridge segment model 5 is rotatably arranged on the second end of the support frame 3 through the swing mechanism 4. The present invention provides displacement and vibration of the model in the vertical direction through a lifting mechanism, and the swing mechanism can provide periodic rotation and swing around the axial direction of the bridge segment model while the bridge model obtains up and down displacement and vibration, thereby realizing three-degree-of-freedom motion simulation of the bridge model and being able to reproduce the bridge vibration scene more realistically and accurately, especially being able to reproduce the real bridge vortex-induced vibration and flutter scenes, thereby improving the simulation and accuracy of the bridge wind-induced vibration scene simulation.

[0052] refer to Figure 2 The lifting mechanism 2 includes a linear motor 2.1 and a sliding plate 2.2; the linear motor 2.1 is fixedly arranged in the mounting groove 1.2, and the sliding plate 2.2 is fixedly connected to the output end of the linear motor 2.1; the mounting groove 1.2 is arranged along the vertical direction, and the sliding plate 2.2 is used for reciprocating linear motion in the mounting groove 1.2 along the vertical direction; the sliding plate 2.2 is also connected to the fixed plate 3.1 at the first end of the support frame 3. The linear motor is installed in the mounting groove by bolts, and its power output end is connected to the support frame to drive the support frame to drive the swing mechanism to move in the three-dimensional space coordinate system.

[0053] The sliding plate 2.2 and the fixing plate 3.1 are connected by bolts.

[0054] refer to Figure 3 The side of the support frame 3 is a triangular structure, preferably a horizontal triangular prism frame structure, a fixed plate is set on one of the edges of the triangular prism as the first end of the support frame, and a set of swing mechanisms and bridge segment models are set on the other two edges as the second end of the support frame; and the two sets of swing mechanisms 4 are located on the same vertical line.

[0055] Through the above settings, two groups, upper and lower, are set as controls; the upper model is the test model; the lower model is the compensation model. During the wind tunnel test, the test model is placed in the test section of the wind tunnel test room, and the incoming flow direction is perpendicular to the axis direction of the test model; the compensation model is set outside the wind tunnel test section and below the test model. When the test device is actuated, the linear motor pushes the rigid support frame, thereby driving the vertical vibration of the test model and the compensation model to ensure that the test model and the compensation model have exactly the same vertical displacement; for the swing motor, the test model and the compensation model can achieve synchronous torsional vibration under the input control of an external signal.

[0056] refer to Figure 4 The swing mechanism 4 includes a swing motor 4.1 (or a torsion motor), a cylindrical sleeve 4.2, a bearing 4.3 and a swing motor mounting plate 4.4; the bearing 4.3 and the swing motor 4.1 are relatively arranged on the support frame 3, and the swing motor 4.1 and the support frame 3 are connected through the swing motor mounting plate 4.4; the cylindrical sleeve 4.2 is arranged in the bearing 4.3 and connected to the inner ring of the bearing, so that the cylindrical sleeve rotates relative to the bearing; one end of the bridge segment model 5 is connected to the cylindrical sleeve 4.2, and the other end is connected to the swing motor 4.1 in transmission.

[0057] When a bridge wind tunnel test device is actuated, according to the actuation requirements, an external control device inputs driving signals such as the balance position, vibration amplitude, and vibration frequency to the swing motor, thereby driving the output flange to drive the bridge segment model, and realizing the multi-modal coupling vibration of the three degrees of freedom (up, down, and rotation), so as to better simulate the bridge vibration scene in the actual wind field. The linear motor and the swing motor are respectively connected to the adapter driver, and are uniformly connected to the electric control cabinet for power supply and drive, and the signal is finally connected to the computer through the switch; the vertical vibration and torsional vibration of the above-mentioned test model and compensation model can be realized through the control software, and the above-mentioned two vibration forms can be realized separately through the synchronous control software, and the linear motor and the swing motor can also be synchronously controlled to realize the coupling of the two vibration forms.

[0058] The bearings and columnar sleeves are used to ensure free rotation of the bridge segment model when the swing motor is actuated, and can be replaced by another set of swing motors and swing motor mounting plates, and ensure synchronization of the two sets of swing motors when actuated.

[0059] The bridge segment model 5 is provided with a first-type through rod 5.2 penetrating along its length direction, with both ends of the first-type through rod protruding from the skeleton end plate by an appropriate length, and connecting plates are provided at both ends of the first-type through rod, and no fixing treatment is performed between the first-type through rod and the carbon fiber skeleton; one end of the first-type through rod 5.2 is connected to the columnar sleeve 4.2 through the left connecting plate 5.3, and the other end is connected to the output flange of the swing motor 4.1 through the right connecting plate 5.4.

[0060] The columnar sleeve 4.2 comprises a sleeve body 4.21 and a sleeve connecting disk 4.22, the sleeve body 4.21 is fixedly connected to the sleeve connecting disk 4.22; the left connecting disk 5.3 is connected to the sleeve connecting disk 4.22, and the sleeve body 4.21 is arranged in the bearing 4.3.

[0061] A plurality of groups of second-type through rods 5.5 are also arranged throughout the length direction of the skeleton 5.1 of the bridge segment model 5; in the present embodiment, two groups of second-type through rods are arranged and symmetrically distributed below the first-type through rods, and both ends of the second-type through rods are extended to the inner surface of the end plate of the skeleton, and the second-type through rods are fixed to the carbon fiber skeleton.

[0062] An upper force plate 5.6 is further provided on the first type through rod 5.2, and multiple groups of the second type through rods 5.5 are connected via a lower force plate; the upper force plate 5.6 and the lower force plate 5.7 are further connected via a force sensor.

[0063] See also Figure 5 The middle part of the lower force plate is concave, and the two ends are respectively overlapped on the two groups of the second-type through rods and bolted and fastened; in order to accurately measure the real-time force measurement data of the bridge segment model when the test device is actuated, a six-dimensional force sensor is arranged between the upper force plate and the lower force plate, and is clamped and fixed with bolts.

[0064] Partition plates 5.8 are also arranged at intervals in the skeleton 5.1; the skeleton 5.1 of the bridge segment model 5 is made of carbon fiber material, and the cross section of the skeleton 5.1 is a triangular structure.

[0065] The first type through rod 5.2 and the second type through rod 5.5 are made of aluminum alloy.

[0066] In order to ensure the supporting capacity, the side of the installation slot 1.2 is also provided with a plurality of groups of strengthening diagonal braces 6, one end of the strengthening diagonal brace 6 is fixedly connected to the base 1.1, and the other end is fixedly connected to the side of the installation slot 1.2. The strengthening diagonal brace is arranged around the installation slot and is used to connect the base and the installation slot. The strengthening diagonal brace is also used to provide lateral rigidity for the test device, prevent the energy dissipation problem caused by the structural stability of the test device itself, and ensure the reliability and accuracy of the test results.

[0067] In order to improve the vertical stiffness of the test device during operation, the support frame is a carbon fiber frame. The sides of the support frame can be replaced by a whole carbon fiber plate, and the cross braces of the support frame can also be replaced by carbon fiber materials, while meeting the lightweight and high-strength requirements of the rigid support.

[0068] When the bridge wind tunnel test device of this embodiment is used for testing, during installation and debugging, it is necessary to first determine a maximum rectangular cross-sectional size in combination with the wind tunnel size and the cross-sectional size of the scaled segment model of the actual bridge; the frequency and amplitude of the torsional vibration of the model are confirmed based on the moment of inertia of the maximum rectangular cross-sectional size in combination with the bridge flutter specification, and the continuous and peak torque of the swing motor are inferred; based on the confirmed parameters of the swing motor and the segment model, combined with the frequency and amplitude of the vertical vibration of the bridge segment model, the peak and continuous thrust levels of the linear motor are finally confirmed; through the electronic pressure scanning valve and the six-dimensional force sensor, the data are aggregated to the computer through their respective data collectors, and the linear motor and the swing motor, in addition to driving the model to move, also record the model displacement time history information when the device is actuated, and act as a displacement sensor; finally, combined with the above-mentioned wind pressure, aerodynamic load, amplitude and other data information, the intrinsic correlation and mutual interaction of the above parameters are studied to reveal the mechanism of wind-induced vibration of the bridge.

[0069] Through the bridge wind tunnel test device of this embodiment, a three-degree-of-freedom high-speed electric test platform and a precise synchronous control system are provided. When studying the influence of environment and inertia, aerodynamic load testing technology and equipment are eliminated, and the focus is on real-time and accurate tracking of the wind-induced vibration response of the model in real-time aerodynamic hybrid simulation. Vortex vibration and flutter wind tunnel tests of bridge segment models are carried out, and the model surface wind pressure and the overall aerodynamic load of the tested model are obtained in a timely and accurate manner during the wind tunnel test. According to the wind pressure distribution on the surface of the tested model and the aerodynamic load level, the relationship between the two is deeply studied, thereby revealing the mechanism of bridge vortex vibration and flutter.

[0070] This embodiment also provides a bridge wind tunnel test method, using the bridge wind tunnel test device as described above, including the following steps:

[0071] Step 1: Debug the bridge wind tunnel test device to keep the mass, aerodynamic shape and test environment of the two groups of bridge segment models consistent, and establish the test model and compensation model of the bridge segment model;

[0072] Step 2: According to the actuation requirements, the external control device inputs a driving signal to the linear motor and the swing motor to realize the multi-modal coupling vibration of three degrees of freedom of the test model and the compensation model;

[0073] The swing motor input includes driving signals such as equilibrium position, vibration amplitude and vibration frequency, thereby driving the output flange to drive the bridge segment model to achieve the three-degree-of-freedom multi-modal coupled vibration, thereby better simulating the bridge vibration scene in the actual wind field. The experiment realizes the simulation and reproduction of the wind-induced response of the bridge through the movement of the linear motor and the swing motor.

[0074] Step 3: During the test, the six-dimensional force sensor located in the above-mentioned test model will synchronously feed back the data collected in real time from each load to the data acquisition end, collect the load data collected by the six-dimensional force sensors of the test model and the compensation model during the multi-modal coupling vibration, and at the same time, record and save the actuation data of the linear motor and the swing motor in real time through the control system;

[0075] Step 4: Process the data collected by the compensation model and the test model to obtain the model aerodynamic force without environmental and inertial interference. Specifically:

[0076] The displacement generated by the vibration of the compensation model is , which includes Axis direction and The degree of freedom of motion in the direction of The axis direction is the vertical direction of the linear motor. The direction of freedom is the direction of rotation of the swing motor;

[0077] The test object will squeeze the air around it and produce friction with it, generating additional non-wind-induced self-excited forces on the surface of the bridge segment model. Obtain the additional self-excited force generated by the compensation model that is not caused by wind , while compensating for the fact that the model is also subject to gravity and environmental vibration , It is expressed as follows:

[0078] ;

[0079] in, is the non-wind-induced additional mass coefficient, is the non-wind-induced additional damping coefficient, To compensate for the model mass; both are related to the aerodynamic shape, air density, air pressure, temperature and other parameters of the bridge segment model.

[0080] During the test, the compensation model will be placed in place and the balance will be cleared to remove the gravity of the compensation model. The dynamic balance test result of the compensation model is It is expressed as:

[0081] 1);

[0082] For the test model, its displacement is also controlled by the test device, so the displacement caused by the vibration of the test model Displacement generated by the compensation model Exactly the same, compared to the compensation model, the test model is still in the wind tunnel test section and is subjected to wind loads ;

[0083] Dynamic balance test results of the test model It is expressed as:

[0084] 2);

[0085] in, To test the quality of the model, To test the model's environmental vibration, The non-wind-induced additional self-excited forces generated for the test model;

[0086] Since the test environment (i.e. air density, air pressure and temperature, etc.), model mass and aerodynamic shape of the compensation model and the test model are the same, ;

[0087] From equation 2) and equation 1), we can obtain the model aerodynamic force that eliminates the environment and inertial interference in real time. After obtaining the model aerodynamic force that eliminates the environment and inertial interference in real time, according to the motion mck equation, , In order to eliminate the model aerodynamic force of environmental and inertial interference in real time, the displacement is back-calculated The value is then input to the motor in real time for amplitude The vibration of the bridge is derived from the new aerodynamic model that eliminates the environmental and inertial interference in real time. The whole process of wind-induced vibration response of the bridge is simulated by iterating repeatedly.

[0088] There are certain limitations in the measurement of aerodynamic forces in existing bridge wind tunnel tests. It is difficult to accurately measure the instantaneous aerodynamic load of the object under test by traditional force measurement methods. The dynamic balance can more accurately measure the overall aerodynamic load of the object under test and is often used to measure the aerodynamic load of structures with complex aerodynamic shapes. However, affected by factors such as the rotation of the wind tunnel motor, the interaction between the wind and the tunnel body and diversion facilities, and the fluid-solid coupling between the wind and the object under test, the instantaneous measurement results of the dynamic balance mainly include aerodynamic loads, inertial loads, and interference caused by random vibrations in the environment. Studies have shown that the inertial load value is often several times that of the aerodynamic load, and the inertial load and the aerodynamic load are often coupled together at the same frequency. Therefore, it is extremely difficult to accurately extract the instantaneous aerodynamic load of the object under test from the measurement results of the dynamic balance in the traditional force measurement method. When the dynamic balance is used for force measurement, the measurement accuracy of the aerodynamic load of the object under test when it is stationary is at a high level. Through the above test method, all loads are synchronously sampled at the microsecond level, and a series of algorithms are used to obtain the model aerodynamic force that eliminates environmental and inertial interference.

[0089] The above descriptions are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may be modified and varied in various ways within the spirit and principles of the present invention.

Claims

1. A bridge wind tunnel test device, characterized in that: It comprises a base (1), a lifting mechanism (2), a support frame (3), a swing mechanism (4) and a bridge segment model (5); The base (1) comprises a pedestal (1.1) and a mounting groove (1.2), wherein the mounting groove (1.2) is arranged on the pedestal (1.1); The lifting mechanism (2) is arranged in the installation groove (1.2), and its output end is connected to the first end of the support frame (3) to drive the support frame (3) to perform reciprocating linear motion in the vertical direction; The second end of the support frame (3) is provided with a swing mechanism (4), and the bridge segment model (5) is rotatably arranged on the second end of the support frame (3) via the swing mechanism (4); The bridge segment model (5) is provided in two groups, an upper group and an lower group, wherein the upper group is a test model and the lower group is a compensation model; during the wind tunnel test, the test model is placed in the wind tunnel test section, and the incoming flow direction is perpendicular to the axial direction of the test model; the compensation model is arranged outside the wind tunnel test section and below the test model.

2. A bridge wind tunnel test device according to claim 1, characterized in that: The lifting mechanism (2) comprises a linear motor (2.1) and a sliding plate (2.2); The linear motor (2.1) is fixedly arranged in the mounting groove (1.2), and the sliding plate (2.2) is fixedly connected to the output end of the linear motor (2.1); The installation groove (1.2) is arranged along the vertical direction, and is used for the sliding plate (2.2) to perform reciprocating linear motion in the installation groove (1.2) along the vertical direction; The sliding plate (2.2) is also connected to the fixed plate (3.1) at the first end of the support frame (3).

3. A bridge wind tunnel test device according to claim 1, characterized in that: The side surface of the support frame (3) is a triangular structure, and the swing mechanisms (4) are arranged at the two corners of the second end of the support frame (3); and the two groups of the swing mechanisms (4) are located on the same vertical line.

4. A bridge wind tunnel test device according to claim 1, characterized in that: The swing mechanism (4) comprises a swing motor (4.1), a columnar sleeve (4.2) and a bearing (4.3); The bearing (4.3) and the swing motor (4.1) are arranged relatively on the support frame (3), and the columnar sleeve (4.2) is arranged in the bearing (4.3); one end of the bridge segment model (5) is connected to the columnar sleeve (4.2), and the other end is drivingly connected to the swing motor (4.1).

5. A bridge wind tunnel test device according to claim 4, characterized in that: A first-type through rod (5.2) is provided on the bridge segment model (5) along its length direction, one end of the first-type through rod (5.2) is connected to the columnar sleeve (4.2) via a left connecting plate (5.3), and the other end is connected to the output flange of the swing motor (4.1) via a right connecting plate (5.4).

6. A bridge wind tunnel test device according to claim 5, characterized in that: The columnar sleeve (4.2) comprises a sleeve body (4.21) and a sleeve connecting disk (4.22), the sleeve body (4.21) being fixedly connected to the sleeve connecting disk (4.22); the left connecting disk (5.3) being connected to the sleeve connecting disk (4.22), and the sleeve body (4.21) being arranged in a bearing (4.3).

7. A bridge wind tunnel test device according to any one of claims 5 or 6, characterized in that: The skeleton (5.1) of the bridge segment model (5) is also provided with a plurality of groups of second-type through rods (5.5) running through the length direction thereof; An upper force plate (5.6) is also provided on the first type through rod (5.2), and multiple groups of the second type through rods (5.5) are connected via a lower force plate (5.7); the upper force plate (5.6) and the lower force plate (5.7) are also connected via a force sensor.

8. A bridge wind tunnel test device according to claim 7, characterized in that: Partition plates (5.8) are also arranged at intervals inside the frame (5.1); the frame (5.1) of the bridge segment model (5) is made of carbon fiber material, and the cross section of the frame (5.1) is in a triangular structure.

9. The bridge wind tunnel test device according to claim 1, characterized in that: The side surface of the installation groove (1.2) is also provided with a plurality of groups of reinforcing diagonal braces (6), one end of the reinforcing diagonal brace (6) is fixedly connected to the base (1.1), and the other end is fixedly connected to the side surface of the installation groove (1.2).

10. A bridge wind tunnel test method, characterized in that: Using a bridge wind tunnel test device as described in any one of claims 7 to 9 comprises the following steps: Step 1: Debug the bridge wind tunnel test device to keep the mass, aerodynamic shape and test environment of the two groups of bridge segment models consistent, and establish the test model and compensation model of the bridge segment model; Step 2: According to the actuation requirements, the external control device inputs a driving signal to the linear motor and the swing motor to realize the multi-modal coupling vibration of the three degrees of freedom of the test model and the compensation model; Step 3: Collect the load data collected by the six-dimensional force sensors of the test model and the compensation model during the multi-modal coupling vibration process, and at the same time record and save the actuation data of the linear motor and the swing motor in real time through the control system; Step 4: Process the data collected by the compensation model and the test model to obtain the model aerodynamic force without environmental and inertial interference. Specifically: The displacement generated by the vibration of the compensation model is X 补 , which includes movement in the z-axis direction and the α-degree of freedom direction, the z-axis direction is the vertical direction of the linear motor, and the α-degree of freedom direction is the rotation direction of the swing motor; According to X 补 Obtain the additional non-wind-induced self-excited force F generated by the compensation model 补-nonwind , while the compensation model is also subject to gravity m 补 g and ambient vibration F 补-wn , F 补-wn It is expressed as follows: Where m0 is the non-wind-induced additional mass coefficient, c0 is the non-wind-induced additional damping coefficient, and m 补 To compensate for model quality; During the test, the compensation model will be placed in place and the balance will be cleared to zero, directly eliminating the gravity of the compensation model. The dynamic balance test result F of the compensation model is 补-total It is expressed as: The displacement X generated by the vibration of the test model 测 The displacement X generated by the compensation model 补 Exactly the same, compared with the compensation model, the test model is still in the wind tunnel test section and is subjected to the wind load F wind ; Dynamic balance test results of the test model F 测-total It is expressed as: Among them, m 测 To test the model quality, F 测-wn is the environmental vibration of the test model, F 测-nonwind The non-wind-induced additional self-excited forces generated for the test model; Since the test environment, model mass and aerodynamic shape of the compensation model and the test model are the same, From equation 2) and equation 1), the model aerodynamic force is obtained by eliminating the environmental and inertial interference in real time.

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