Test model and method for simulating seismic soil evolution of long-span bridge

Abstract

The application relates to the field of earthquake simulation and detection, and discloses a test model for simulating seismic soil evolution of a large-span bridge and a testing method, the test model comprising a vibration table, a large-span bridge model, a damping control device, a vibration mechanism and a cooperative control system, the large-span bridge model comprising a plurality of pier bases, the damping control device being fixedly connected between the pier bases and the vibration table; the vibration mechanism cooperatively drives the vibration table to vibrate in space; the cooperative control system comprises a processor, an acceleration sensor and a displacement sensor; the testing method comprises the steps of simulating an earthquake process by the vibration table, simulating soil evolution or different site geology by the damping control device, collecting acceleration and displacement data information of the damping control device in real time by the cooperative control system, and analyzing the structural response of the large-span bridge. The test model can simulate the seismic site effect and the bridge seismic response under non-uniform excitation, has high authenticity and accuracy, is widely applicable, and has low test cost.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of earthquake simulation and detection, in particular to a test model and a testing method for simulating seismic soil evolution of a large-span bridge. BACKGROUND

[0002] The disaster caused by the earthquake is mainly due to the fact that the earthquake spreads to the ground in the form of waves, and the energy is dissipated and spread outward. The destructive effect of the earthquake must be transmitted through the site. The structure is also dependent on the site. Different site conditions have different abilities to propagate seismic waves and different degrees of seismic response. Therefore, the premise of seismic analysis is to analyze the seismic response of the site, that is, to solve the dynamic parameters of the soil under the action of the earthquake. The large-span bridge structure has a large weight, a high gravity center and weak lateral stiffness. The influence of the soil effect under the action of the earthquake is more significant. Therefore, it is of great significance to carry out simulation tests on the influence of the soil evolution under the action of the earthquake on the large-span bridge.

[0003] Chinese patent CN110108427B discloses a "bridge loading simulation test device". The test device includes a test table, a support, a simulation beam, a vibration system and a control system. The support is installed on the test table, the simulation beam is installed on the top of the support, and the vibration system is installed on the support or the test table and also contacts the bottom of the simulation beam. The vibration system is connected with the control system, and generates vibrations of different frequencies and / or amplitudes under the control of the control system, and transmits the vibrations to the simulation beam. The test device specifically simulates the deformation and vibration of the bridge in the earthquake. However, for a large-span bridge, the influence of the soil evolution in the earthquake on the bridge structure needs to be considered. The technical solution of the patent cannot meet the simulation requirements. SUMMARY

[0004] The purpose of the present application is to provide a test model and a testing method for simulating seismic soil evolution of a large-span bridge. The damping control device and the cooperative control system are combined under a vibration table, the soil evolution process is considered, the seismic response simulation of the bridge under the seismic site effect and the non-uniform excitation is realized, and the seismic test model of the large-span bridge under various application conditions is satisfied.

[0005] Technical solution: the test model for simulating seismic soil evolution of a large-span bridge, the test model comprises:

[0006] a vibration table;

[0007] a large-span bridge model, the large-span bridge model comprises a bridge body and a plurality of pier bases supporting the bridge body;

[0008] a damping control device, the damping control device comprises a plurality of groups fixedly connected at the bottom end of the pier base, and the damping control device is fixedly connected to the vibration table.

[0009] a vibration mechanism comprising a plurality of groups arranged around the vibration table, the vibration mechanism driving the vibration table to vibrate along the spatial coordinates X / Y / Z;

[0010] a cooperative control system comprising a processor arranged in the damping control device respectively, and an acceleration sensor and a displacement sensor electrically connected with the processor, the acceleration sensor and the displacement sensor collecting acceleration and displacement data information of the damping control device respectively and feeding back the data information to the processor for processing.

[0011] Preferably, the damping control device comprises a mounting base plate and a damping cylinder fixedly arranged on the mounting base plate.

[0012] The damping cylinder comprises a cylinder body, a vertical displacement assembly arranged in the cylinder body, the displacement assembly being movable along its axial and radial directions, and a mounting top plate arranged at the top end of the displacement assembly.

[0013] Preferably, the inner cavity of the cylinder body is divided into an upper cavity and a lower cavity by a partition plate, the upper cavity contains a magneto-rheological fluid, and an axial hole and a sealing plate sealing the axial hole are respectively arranged at the top and bottom center of the upper cavity.

[0014] The displacement assembly comprises a moving shaft, the moving shaft extending through the upper cavity to the lower cavity, and a mounting column arranged at the middle part of the moving shaft, the mounting column comprising a mounting cavity arranged therein, and the mounting column being arranged in the upper cavity.

[0015] The top end of the moving shaft is fixedly connected with the mounting top plate, and the bottom end of the moving shaft is provided with a support disc arranged in the lower cavity.

[0016] First electromagnetic units are respectively arranged in the circumferential side wall of the upper cavity and the circumferential side wall of the mounting column, the first electromagnetic units generating electromagnetic fields after being energized.

[0017] Second electromagnetic units are respectively arranged in the circumferential direction of the support disc and the circumferential direction of the bottom plate of the lower cavity, the second electromagnetic units generating electromagnetic fields after being energized.

[0018] Preferably, the processor and the acceleration sensor are arranged in the mounting column, and the displacement sensor is arranged on the support disc.

[0019] Preferably, the processor comprises a control module, and an adjustable band-pass filter module, a signal amplification module and a current driving module connected with the control module.

[0020] Preferably, the vibration mechanism comprises a driving cylinder and a transmission mechanism.

[0021] The transmission mechanism comprises a support slot block fixedly connected to the side wall of the vibration table, a support block is connected in the support slot block through a vertically arranged first hinge shaft and a horizontally arranged second hinge shaft, and the support block is fixedly connected to the front end of the piston rod of the driving cylinder.

[0022] Preferably, the inner wall of the cylinder of the lower cavity is provided with an anti-collision foam layer.

[0023] Preferably, a magnetic isolation layer is attached to the side wall of the cylinder of the upper cavity.

[0024] Preferably, a plurality of positioning holes are uniformly distributed on the plate surface of the vibration table.

[0025] The application further discloses a test method for simulating the dynamic response of a test model, which comprises the following steps:

[0026] Step 1: connecting the vibration table to the support frame through the circumferentially arranged groups of vibration mechanisms, and keeping the vibration table in a suspended state;

[0027] Step 2: fixing and installing the damping control devices consistent in number with the pier bases on the corresponding positions of the vibration table according to the size of the long-span bridge model and the corresponding positions of the pier bases, hoisting the long-span bridge model above the damping control devices by a crane, and fixedly connecting the pier bases to the damping control devices through fixing bolts;

[0028] Step 3: simulating the soil layer characteristics of the long-span bridge by the vibration table according to the structural size of the long-span bridge, setting the initial parameters of the soil layer according to the test requirements, and controlling the vibration table to vibrate at the required frequency driven by the vibration mechanisms;

[0029] Step 4: vibrating the vibration table along the spatial coordinates X / Y / Z and transmitting the vibration to each damping control device, causing the displacement components of the damping control device to displace laterally and / or longitudinally along the inner cavity of the damping cylinder; the displacement components transmit the vibration to the long-span bridge model;

[0030] Step 5: the acceleration sensor and the displacement sensor in the cooperative control system respectively collect the displacement and acceleration data information of the displacement components, and transmit the data information to the processor for processing; the data information is subjected to adjustable band-pass filtering, the band-pass range is determined according to the soil body properties, and after signal amplification, the size of the damping is re-adjusted and set, and the damping force is further adjusted in real time through current driving, the soil body property evolution process is simulated, the cooperative control systems are cooperatively controlled, the seismic site effect and the bridge seismic response simulation under multi-point non-uniform excitation are realized, and finally the dynamic response data of the long-span bridge in the earthquake process are collected, so as to analyze the structural response of the long-span bridge.

[0031] Compared with the prior art, the application has the following beneficial effects:

[0032] 1. The test model of this invention can set initial soil parameters according to test requirements and input current drive. When the vibration table vibrates at a set frequency, the vibration table transmits the vibration to the damping control device, causing the tremor component to displace within the damping cylinder. Acceleration sensors and displacement sensors respectively collect acceleration and displacement data from the damping control device and feed the data back to the processor for processing. After receiving the data, the processor performs adjustable bandpass filtering, the bandpass range of which is determined according to the soil properties. After signal amplification, it can combine historical data and current displacement and acceleration data to adjust the corresponding damping according to the set soil characteristics. The damping adjustment control is achieved by converting current drive into magnetic field change. By utilizing the change in the magnetic field of the environment where the magnetorheological fluid is located, the magnitude of the damping force is changed, thereby simulating the evolution process of soil properties. The various collaborative control systems coordinate to achieve simulation of bridge seismic response under seismic site effects and multi-point non-uniform excitation. Finally, the dynamic response data of long-span bridges during the seismic soil evolution process are collected to analyze the structural response of long-span bridges.

[0033] 2. During an earthquake, soil may liquefy, causing changes in soil properties that can affect the structure. This invention can collect and record time-history data during vibration, and combine this with instantaneous data to calculate and adjust damping forces to study the impact of changes in soil properties on the structure under earthquake loading.

[0034] 3. Coordinated control among various control systems can assist the shaking table in simulating the seismic site effect and the seismic response of bridges under non-uniform excitation, realistically simulating the dynamic response of the foundation structure of each pier of a long-span bridge, and improving the realism and accuracy of the experimental model.

[0035] 4. The damping control device and collaborative control system facilitate disassembly or installation on the shaking table and adjustment of the seismic excitation position; it is applicable to large-span bridge models of different scales, with a wide range of applications, reducing test costs and site and equipment requirements. Attached Figure Description

[0036] Figure 1 This is a three-dimensional structural diagram of the experimental model of the present invention;

[0037] Figure 2 for Figure 1 Schematic diagram of the installation structure of the bridge pier base and damping control device;

[0038] Figure 3 for Figure 2 Schematic diagram of the internal structure of the medium damping control device;

[0039] Figure 4 for Figure 2 Cross-sectional view of the intermediate damping control device along its axial direction;

[0040] Figure 5 A schematic diagram of a test model workflow of the present application.

[0041] Reference signs:

[0042] 1, vibration table; 11, positioning hole;

[0043] 2, large-span bridge model; 21, pier base; 211, connecting base plate;

[0044] 3, damping control device; 31, mounting base plate; 32, damping cylinder; 321, cylinder body; 322, partition plate; 323, upper cavity; 324, lower cavity; 325, anti-collision foam layer; 326, shaft hole; 33, mounting top plate; 34, displacement assembly; 341, moving shaft; 342, mounting column; 343, support disc; 35, connecting hole; 36, sealing plate; 37, first electromagnetic unit; 38, second electromagnetic unit; 39, magnetic isolation layer; 310, magnetorheological fluid;

[0045] 4, vibration mechanism; 41, driving cylinder; 42, transmission mechanism; 421, support slot block; 422, support block; 423, first hinged shaft; 424, second hinged shaft;

[0046] 5, fixing bolt;

[0047] 6, cooperative control system; 61, processor; 62, acceleration sensor; 63, displacement sensor. DETAILED DESCRIPTION

[0048] In order to make the purpose, technical scheme and advantages of the embodiments of the present application more clear, the following will combine the drawings of the embodiments of the present application to clearly and completely describe the technical scheme of the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the described embodiments of the present application, all other embodiments obtained by those skilled in the art belong to the scope of protection of the present application. Figures 1-5

[0049] Embodiment 1:

[0050] In combination with Figures 1-2 ​As shown, the test model for simulating seismic soil evolution of a large-span bridge of the present application comprises a vibration table 1, a large-span bridge model 2, a damping control device 3, a vibration mechanism 4 and a cooperative control system 6. A plurality of positioning holes 11 are uniformly distributed on the surface of the vibration table 1, which can meet the fixing and installation of the large-span bridge model 2 of various sizes on the vibration table 1. A plurality of vibration mechanisms 4 are arranged around the vibration table 1. The vibration mechanism 4 comprises a driving cylinder 41 and a transmission mechanism 42. The transmission mechanism 42 comprises a support groove block 421 fixedly connected to the side wall of the vibration table 1. A support block 422 is connected in the support groove block 421 through a first hinge shaft 423 arranged vertically and a second hinge shaft 424 arranged horizontally. The support block 422 is fixedly connected to the front end of the piston rod of the driving cylinder 41. The support block 422 can rotate along the support groove block 421 through the first hinge shaft and the second hinge shaft, respectively. The driving cylinder 41 can be a driving air cylinder, a driving electric steel or a driving oil cylinder. Each driving cylinder 41 is controlled by a separate frequency converter. The plurality of vibration mechanisms 4 cooperatively drive the vibration table 1 to vibrate along the spatial coordinates X / Y / Z, so as to simulate the non-uniform excitation of the soil during the earthquake process through the vibration table 1, to truly simulate the dynamic response of the structure of each pier base 21 of the large-span bridge, and to improve the authenticity and accuracy of the test model.

[0051] The large-span bridge model 2 comprises a bridge body and a plurality of pier bases 21 arranged along the length direction of the bridge body. A connecting base plate 211 is arranged at the bottom of the pier base 21. The damping control device 3 is fixedly connected to the bottom end of each pier base 21 and fixedly connected to the corresponding position of the vibration table 1. The simulated vibration of the vibration table 1 can be transmitted to the large-span bridge model 2 through the damping control device 3.

[0052] As shown, Figures 3-4 The damping control device 3 comprises a mounting base plate 31 and a damping cylinder 32 fixedly arranged on the mounting base plate. The damping cylinder 32 comprises a cylinder body 321. A shifting assembly 34 is arranged vertically in the cylinder body 321. The shifting assembly 34 can shift along its axial direction and radial direction. A mounting top plate 33 is arranged at the top end of the shifting assembly 34. Connection holes 35 are formed in the mounting base plate 31 and the mounting top plate 33, respectively. The connecting base plate 211 is fixedly connected to the mounting base plate 31 through fixing bolts 5. The mounting base plate 31 is fixedly connected to the vibration table 1 through the fixing bolts 5.

[0053] The inner cavity of the cylinder 321 is divided into an upper cavity 323 and a lower cavity 324 by a partition plate 322. The upper cavity 323 contains a magneto-rheological fluid 310, and an axle hole 326 is formed in the center of the top and bottom of the upper cavity 323, and a sealing plate 36 is arranged to block the axle hole. The moving assembly 34 includes a moving shaft 341, which extends through the upper cavity 323 to the lower cavity 324. The moving shaft 341 penetrates the center of the two sealing plates 36 and can move up and down with a small displacement. A mounting column 342 is arranged in the middle of the moving shaft 341, and a mounting cavity is arranged in the mounting column 342. The mounting column 342 is located in the upper cavity 323. A first electromagnetic unit 37 is arranged in the circumferential side wall of the upper cavity 323 and the circumferential side wall of the mounting column 342. The first electromagnetic unit 37 generates an electromagnetic field after being electrified. The moving shaft 341 is fixedly connected to the mounting top plate 33 at the top end, and a support disc 343 is arranged at the bottom end of the moving shaft 341 and located in the lower cavity 324. A second electromagnetic unit 38 is arranged in the circumferential direction of the support disc 343 and the bottom plate of the lower cavity 324. The second electromagnetic unit 38 generates an electromagnetic field after being electrified, so that a repulsive force is formed between the support disc 343 and the bottom surface of the cylinder 321, and the moving assembly 34 is in a suspended state, reducing the frictional force during movement.

[0054] A collision-proof foam layer 325 is arranged on the inner wall of the cylinder in the lower cavity 324, which can prevent the displacement of the moving assembly 34 from exceeding the limit when moving in the inner cavity of the cylinder 321.

[0055] A magnetic isolation layer 39 is attached to the side wall of the upper cavity 323, which can prevent magnetic leakage in the cylinder 321 and improve the damping performance of the damping control device 3.

[0056] The test model also comprises a cooperative control system 6, which comprises a processor 61 and an acceleration sensor 62 and a displacement sensor 63 electrically connected to the processor 61, the processor 61 and the acceleration sensor 62 are arranged in the mounting column 342, and the displacement sensor 63 is arranged on the support disc 343; the processor 61 comprises a control module and an adjustable band-pass filtering module, a signal amplification module and a current driving module connected to the control module, and the control module can adopt a single-chip microcomputer. According to the test requirements, the initial parameters of the soil layer are set, and the current is inputted, when the vibration table 1 vibrates at a set frequency, the vibration table 1 transmits the vibration to the damping control device 3, and causes the displacement assembly 34 to displace in the damping cylinder 32, the acceleration sensor 62 and the displacement sensor 63 collect the acceleration and displacement data information of the damping control device 3 respectively, and feed back the data information to the processor 61 for processing, after the processor 61 receives the data, the data is filtered through the adjustable band-pass filtering, the band-pass range is selected and determined according to the soil body properties, after the signal is amplified, the historical data and the current displacement and acceleration data can be combined, the corresponding damping is adjusted according to the set soil body characteristics, the damping adjustment control is converted into a magnetic field change through current driving, the magnetic field change of the environment where the magnetorheological fluid is located is utilized, and then the damping force size is changed, the soil body property evolution process is simulated, the cooperative control is realized between the cooperative control systems 6, the seismic site effect and the bridge seismic response simulation under multi-point non-uniform excitation are realized, and finally the dynamic response data of the long-span bridge in the seismic process is collected, and the long-span bridge structure response condition is analyzed.

[0057] Embodiment 2

[0058] As shown in Figure 5 The application further discloses a test method for simulating the dynamic response of the test model, and the test method comprises the following steps:

[0059] (1) connecting the vibration table 1 to a support frame (not shown in the figure) through a plurality of groups of vibration mechanisms 4 arranged in the circumferential direction of the vibration table 1; specifically, the outer ends of the drive cylinders 41 of the vibration mechanisms 4 are fixedly connected to the support frame, the vibration table 1 is kept in a suspended state, the vibration table 1 is driven along the space coordinates X / Y / Z by the plurality of groups of vibration mechanisms 4, the non-uniform excitation of the soil body in the seismic process can be simulated by the vibration table 1, and the dynamic response of each pier base 21 structure of the long-span bridge can be truly simulated.

[0060] (2) according to the size of the long-span bridge model 2 and the positions of the corresponding pier bases 21, fixing and installing damping control devices 3 consistent in number with the pier bases on the corresponding positions of the vibration table 1, hoisting the long-span bridge model 2 above the damping control devices 3 by a crane, and fixedly connecting the pier bases 21 and the damping control devices 3 by the fixing bolts 5, so as to keep the consistency of the movement of the damping control devices 3 and the long-span bridge model 2.

[0061] (3) According to the structural size of the long-span bridge, the vibration table 1 simulates the soil layer characteristics of the long-span bridge, sets the initial parameters of the soil layer according to the test requirements, and controls the vibration mechanism 4 to drive the vibration table 1 to vibrate at the required frequency, thereby improving the authenticity of the simulation of the soil characteristics during the earthquake.

[0062] (4) When the vibration table 1 starts to simulate the changes of the soil during the earthquake, the vibration table 1 vibrates along the spatial coordinates X / Y / Z to transmit the vibration to the damping control device 3, causing the displacement assembly 34 of the damping control device 3 to displace laterally or / and longitudinally in the inner cavity of the damping cylinder 32, and the displacement assembly 34 transmits the vibration to the long-span bridge model 2, thereby causing the long-span bridge model to deform during the vibration process, so as to analyze the influence of the changes of the soil caused by the earthquake on the long-span bridge structure.

[0063] (5) System control between each cooperative control system 6, in which the acceleration sensor 62 and the displacement sensor 63 can collect displacement and acceleration data information of the displacement assembly 34 in real time, and transmit the data information to the processor 61 for processing, to collect the dynamic response data of the long-span bridge during the evolution of the earthquake soil, so as to analyze the response of the long-span bridge structure.

[0064] The above is the preferred embodiment of the present application, it should be noted that for those skilled in the art, without departing from the principles of the present application, a number of improvements and refinements can be made, which improvements and refinements should also be considered as the protection scope of the present application.

Claims

1. An experimental model for simulating the seismic soil evolution of long-span bridges, characterized in that, The experimental model includes: Vibration table (1); A long-span bridge model (2) includes a bridge body and multiple pier bases (21) supporting the bridge body. The damping control device (3) includes multiple sets of components fixedly connected to the bottom end of the pier base (21), and is fixedly connected to the vibration table (1). The damping control device (3) includes a mounting base (31) and a damping cylinder (32) fixedly mounted on the mounting base. The damping cylinder (32) includes a cylinder body (321), and a vertically arranged axial movement component (34) is arranged inside the cylinder body (321). The moving component (34) can move axially and radially, and the top of the moving component (34) is provided with a mounting plate (33); the inner cavity of the cylinder (321) is divided into an upper cavity (323) and a lower cavity (324) by a partition plate (322); the upper cavity (323) is filled with magnetorheological fluid (310), and the top and bottom centers of the upper cavity (323) are respectively provided with shaft holes (326) and sealing plates (36) to seal the shaft holes; the moving component (324) can move axially and radially, and the top of the moving component (34) is provided with a mounting plate (33) to seal the shaft holes; the moving component (324) can move axially and radially, and the top of the moving component (34) is provided with a mounting plate (33) to seal the shaft holes; the moving component (324) can move axially and radially, and the top of the moving component (34) is provided with a mounting plate (33) to seal the shaft holes; the moving component (324) can move axially and radially, and the top of the moving component (34) is provided with a mounting plate (33); ... The moving assembly (34) includes a moving shaft (341) that extends through the upper cavity (323) to the lower cavity (324). A mounting post (342) is provided in the middle of the moving shaft (341), and a mounting cavity is provided inside the mounting post (342), which is located inside the upper cavity (323). The top end of the moving shaft (341) is fixedly connected to the mounting top plate (33), and the bottom end of the moving shaft (341) is provided with a mounting plate (33). The lower cavity (324) contains a support plate (343); the upper cavity (323) has a first electromagnetic unit (37) installed in the circumferential side wall of the cylinder and the circumferential side wall of the mounting column (342), which generates an electromagnetic field when energized; the support plate (343) and the lower cavity (324) have a second electromagnetic unit (38) installed in the circumferential direction, which generates an electromagnetic field when energized. Vibration mechanism (4), the vibration mechanism (4) includes multiple sets arranged around the vibration table (1), the vibration mechanism (4) drives the vibration table (1) to vibrate along the spatial coordinates X / Y / Z; The collaborative control system (6) includes a processor (61) respectively installed in the damping control device (3) and an acceleration sensor (62) and a displacement sensor (63) electrically connected to the processor. The acceleration sensor (62) and the displacement sensor (63) respectively collect the acceleration and displacement data information of the damping control device (3) and feed the data information back to the processor for processing.

2. The experimental model for simulating the seismic soil evolution of long-span bridges according to claim 1, characterized in that, The processor (61) and the acceleration sensor (62) are disposed inside the mounting post (342); the displacement sensor (63) is disposed on the support plate (343).

3. The experimental model for simulating the seismic soil evolution of long-span bridges according to claim 2, characterized in that, The processor (61) includes a control module and an adjustable bandpass filter module, a signal amplification module, and a current drive module connected to the control module.

4. The experimental model for simulating the seismic soil evolution of long-span bridges according to claim 1, characterized in that, The vibration mechanism (4) includes a drive cylinder (41) and a transmission mechanism (42). The transmission mechanism (42) includes a support groove block (421) fixedly connected to the side wall of the vibration table (1). A support block (422) is connected to the support groove block (421) through a vertically arranged first hinge shaft (423) and a horizontally arranged second hinge shaft (424). The support block (422) is fixedly connected to the front end of the piston rod of the drive cylinder (41).

5. The experimental model for simulating the seismic soil evolution of long-span bridges according to claim 1, characterized in that, The inner wall of the lower cavity (324) is provided with an anti-collision foam layer (325).

6. The experimental model for simulating the seismic soil evolution of long-span bridges according to claim 1, characterized in that, A magnetic shielding layer (39) is attached to the cylinder side wall of the upper cavity (323).

7. The experimental model for simulating the seismic soil evolution of long-span bridges according to claim 1, characterized in that, The vibration table (1) has multiple positioning holes (11) evenly distributed on its plate surface.

8. A test method for simulating the dynamic response of an experimental model as described in any one of claims 1-7, characterized in that, The testing method includes the following steps: Step 1: Connect the vibration table (1) to the support frame through multiple sets of vibration mechanisms (4) arranged around its circumference, and keep the vibration table (1) in a suspended state; Step 2: Based on the dimensions of the long-span bridge model (2) and the corresponding pier base (21) position, fix the damping control device (3) with the same number of pier bases at the corresponding position on the vibration table (1), hoist the long-span bridge model (2) above the damping control device (3) with a crane, and fix the pier base (21) and damping control device (3) with fixing bolts (5); Step 3: Based on the structural dimensions of the long-span bridge, a shaking table (1) is used to simulate the soil characteristics of the long-span bridge. The initial parameters of the soil are set according to the test requirements, and the vibration mechanism (4) is controlled to drive the shaking table (1) to vibrate at the required frequency. Step 4: The vibration table (1) vibrates along the spatial coordinates X / Y / Z and transmits the vibration to each damping control device (3), causing the lateral displacement (34) of the damping control device (3) to move laterally or / and longitudinally along the inner cavity of the damping cylinder (32); the lateral displacement (34) transmits the vibration to the long-span bridge model (2). Step 5: The acceleration sensor (62) and displacement sensor (63) in the collaborative control system (6) respectively collect the displacement and acceleration data of the tremor component (34) and transmit the data to the processor (61) for processing. The data is filtered by an adjustable bandpass filter. The bandpass range is determined according to the soil properties. After signal amplification, the damping value is readjusted and further adjusted in real time by current drive to simulate the evolution of soil properties. The collaborative control systems (6) coordinate to achieve the simulation of bridge seismic response under seismic site effects and multi-point non-uniform excitation. Finally, the dynamic response data of long-span bridges during the earthquake are collected to facilitate the analysis of the structural response of long-span bridges.

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