Experimental model for simulating seismic soil evolution for long-span bridge, and test method

Abstract

An experimental model for simulating seismic soil evolution for a long-span bridge, comprising a vibration table (1), a long-span bridge model (2), damping control devices (3), vibration mechanisms (4), and cooperative control systems (6), wherein the long-span bridge model (2) comprises a plurality of bridge pier bases (21); the damping control devices (3) are fixedly connected between the bridge pier bases (21) and the vibration table (1); the vibration mechanisms (4) cooperatively drive the vibration table (1) to vibrate in the space; each cooperative control system (6) comprises a processor (61), an acceleration sensor (62) and a displacement sensor (63). A test method for dynamic response simulation of the experimental model comprises the following steps: the vibration table simulates an earthquake process, the damping control devices simulate soil evolution or geology of different sites, and the cooperative control systems acquire and collect acceleration and displacement data information of the damping control devices in real time and analyze structural responses of a long-span bridge. The experimental model can simulate seismic responses of a bridge under seismic site effects and non-uniform excitations, and has high authenticity and accuracy, a wide application range and low experimental cost.

Description

An experimental model and test method for simulating earthquake soil evolution in long-span bridges Technical Field

[0001] The present invention relates to the technical field of earthquake simulation and detection, and in particular to a test model and a test method for simulating earthquake soil evolution of a long-span bridge. Background Art

[0002] The damage caused by earthquakes is primarily due to the propagation of earthquake waves toward the surface, with energy dissipated and transmitted outward. The destructive effects of earthquakes must be transmitted through the site, and structures rely on the site. Different site conditions have different capacities for the propagation of seismic waves and varying degrees of earthquake response. Therefore, a prerequisite for seismic analysis is to conduct a site seismic response analysis, that is, to determine the dynamic parameters of the soil under earthquake action. Long-span bridge structures, with their heavy weight, high center of gravity, and weak lateral stiffness, are more significantly affected by soil effects under earthquakes. Therefore, conducting simulation tests to examine the impact of site soil evolution on long-span bridges under earthquake action is of great significance.

[0003] Chinese patent CN110108427B discloses a "bridge loading simulation test device," which includes a test bench, a bracket, a simulated beam, a vibration system, and a control system. The bracket is mounted on the test bench, the simulated beam is mounted on top of the bracket, and the vibration system is mounted on the bracket or test bench and contacts the bottom of the simulated beam. The vibration system is connected to the control system and, under the control of the control system, generates vibrations of varying frequencies and / or amplitudes, transmitting the vibrations to the simulated beam. This test device specifically simulates the deformation and vibration of a bridge during an earthquake. However, for long-span bridges, the impact of soil evolution during an earthquake on the bridge structure must be considered, and this patented technical solution struggles to meet these simulation requirements.

[0004] Summary of the Invention

[0005] Purpose of the invention: The purpose of the present invention is to provide a test model and test method for simulating the evolution of seismic soil mass in large-span bridges. By combining a damping control device and a coordinated control system under a vibration table, the soil evolution process is taken into account to realize the simulation of the seismic response of bridges under seismic site effects and non-uniform excitation, and to meet the requirements of seismic test models for large-span bridges under various application conditions.

[0006] Technical solution: The present invention provides a test model for simulating the evolution of long-span bridge soil during earthquakes, the test model comprising:

[0007] Vibration table;

[0008] A long-span bridge model, comprising a bridge body and a plurality of pier bases supporting the bridge body;

[0009] a damping control device, the damping control device comprising a plurality of groups fixedly connected to the bottom end of the pier base, the damping control device being fixedly connected to the vibration platform;

[0010] 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;

[0011] A collaborative control system includes a processor respectively arranged in a damping control device and an acceleration sensor and a displacement sensor electrically connected to the processor. The acceleration sensor and the displacement sensor respectively collect acceleration and displacement data information of the damping control device and feed the data information back to the processor for processing.

[0012] Preferably, the damping control device includes a mounting base and a vibration damping cylinder fixedly arranged on the mounting base;

[0013] The vibration damping cylinder includes a cylinder body, in which a moving assembly is vertically arranged. The moving assembly can move along its axial direction and radial direction, and a mounting top plate is arranged on the top of the moving assembly.

[0014] Preferably, the inner cavity of the cylinder is divided into an upper cavity and a lower cavity by a partition plate; the upper cavity contains magnetorheological fluid, and an axial hole and a sealing plate for blocking the axial hole are respectively opened at the top and bottom centers of the upper cavity;

[0015] The movement assembly includes a moving shaft, the moving shaft extends through the upper cavity to the lower cavity, and a mounting column is provided in the middle of the moving shaft, a mounting cavity is provided in the mounting column, and the mounting column is located in the upper cavity;

[0016] The top end of the movable shaft is fixedly connected to the mounting top plate, and the bottom end of the movable shaft is provided with a support plate located in the lower cavity;

[0017] A first electromagnetic unit is provided in the circumferential cylinder side wall of the upper cavity and the circumferential side wall of the mounting column, and generates an electromagnetic field when the first electromagnetic unit is energized;

[0018] The support plate and the bottom plate of the lower cavity are respectively provided with second electromagnetic units, which generate electromagnetic fields when energized.

[0019] Preferably, the processor and the acceleration sensor are arranged in the mounting column; and the displacement sensor is arranged on the supporting plate.

[0020] Preferably, the processor includes a control module and an adjustable bandpass filtering module, a signal amplifying module, and a current driving module connected to the control module.

[0021] Preferably, the vibration mechanism includes a drive cylinder and a transmission mechanism;

[0022] The transmission mechanism includes a support slot block fixedly connected to the side wall of the vibration table, and the support block is connected to the support slot block through a vertically arranged first hinge shaft and a horizontally arranged second hinge shaft. The support block is fixedly connected to the front end of the piston rod of the drive cylinder.

[0023] Preferably, an anti-collision foam layer is provided on the inner wall of the cylinder of the lower cavity.

[0024] Preferably, a magnetic isolation layer is attached to the side wall of the cylinder of the upper cavity.

[0025] Preferably, a plurality of positioning holes are evenly distributed on the surface of the vibration table.

[0026] The present invention also discloses a test method for simulating the dynamic response of a test model, which comprises the following steps:

[0027] Step 1: Connect the vibration table to the support frame through multiple sets of vibration mechanisms arranged around the vibration table, and keep the vibration table in a suspended state;

[0028] Step 2: Based on the size of the long-span bridge model and the location of its corresponding pier bases, install the same number of damping control devices as the pier bases on the corresponding positions of the shaking table. Use a crane to lift the long-span bridge model above the damping control devices, and securely connect the pier bases to the damping control devices with fixing bolts.

[0029] Step 3: Based on the structural dimensions of the long-span bridge, a shaking table is used to simulate the soil characteristics of the long-span bridge. The initial soil parameters are set according to the test requirements, and the vibration mechanism is controlled to drive the shaking table to vibrate at the required frequency.

[0030] Step 4: The shaking table vibrates along the spatial coordinates X / Y / Z and transmits the vibration to each damping control device, causing the moving components of the damping control device to shift laterally and / or longitudinally along the inner cavity of the damping cylinder; the moving components transmit the vibration to the long-span bridge model;

[0031] Step 5: The acceleration sensors and displacement sensors in the collaborative control system respectively collect the displacement and acceleration data information of the moving components and pass the data information to the processor for processing. The data information is filtered through an adjustable bandpass filter, and the bandpass range is determined according to the physical properties of the soil. After signal amplification, the damping size is readjusted and the damping force is further adjusted in real time through current drive to simulate the evolution process of the soil physical properties. The collaborative control systems coordinate control to realize the simulation of the seismic response of the bridge under earthquake site effects and multi-point non-uniform excitation. Finally, the dynamic response data of the long-span bridge during the earthquake is collected to facilitate the analysis of the structural response of the long-span bridge.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] 1. The test model of the present invention can set the initial parameters of the soil layer according to the test requirements and input current drive. When the vibration table vibrates at the set frequency, the vibration table transmits the vibration to the damping control device and causes the moving component to displace in the vibration reduction cylinder. The acceleration sensor and the displacement sensor respectively collect the acceleration and displacement data information of the damping control device and feed the data information back to the processor for processing. After receiving the data, the processor passes it through an adjustable bandpass filter. The bandpass range is determined according to the physical properties of the soil. After signal amplification, the processor 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 converted into magnetic field change by current drive, and the magnetic field change of the environment in which the magnetorheological fluid is located is used to change the damping force, thereby simulating the evolution process of soil physical properties. The coordinated control systems coordinate control to realize the simulation of bridge seismic response under earthquake site effects and multi-point non-uniform excitation. Finally, the dynamic response data of the long-span bridge during the evolution of the earthquake soil is collected to analyze the structural response of the long-span bridge.

[0034] 2. During an earthquake, soil may liquefy, causing changes in soil properties, which in turn can affect structures. This invention can collect and record time-course data during vibration, combine it with instantaneous data, and calculate and adjust the damping force to study the impact of changes in soil properties on structures under earthquake action.

[0035] 3. The coordinated control among the coordinated control systems can assist the shaking table in simulating the earthquake site effects and the seismic response of bridges under non-uniform excitation, and realistically simulate the dynamic response of each pier foundation structure of a long-span bridge, thus improving the authenticity and accuracy of the experimental model.

[0036] 4. The damping control device and coordinated control system are easy to disassemble or install on the vibration table and adjust the seismic excitation position. They are suitable for large-span bridge models of different scales and have a wide range of applications, reducing test costs and site equipment requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] FIG1 is a schematic diagram of the three-dimensional structure of a test model of the present invention;

[0038] FIG2 is a schematic diagram of the installation structure of the pier base and the damping control device in FIG1;

[0039] FIG3 is a schematic diagram of the internal structure of the damping control device in FIG2 ;

[0040] FIG4 is a cross-sectional view of the damping control device in FIG2 along its axial structure;

[0041] FIG5 is a schematic diagram of the working process of the test model of the present invention.

[0042] Figure 1: 1. vibration table; 11. positioning hole; 2. long-span bridge model; 21. pier base; 211. connecting base plate; 3. damping control device; 31. mounting base plate; 32. vibration damping cylinder; 321. cylinder body; 322. partition plate; 323. upper cavity; 324. lower cavity; 325. anti-collision foam layer; 326. axis hole; 33. mounting top plate; 34. movement assembly; 341. moving axis; 342. mounting column; 343. support plate; 35. connecting hole; 36. sealing plate; 37. first electromagnetic unit; 38. second electromagnetic unit; 39. magnetic isolation layer; 310. magnetorheological fluid; 4. vibration mechanism; 41. driving cylinder; 42. transmission mechanism; 421. supporting slot block; 422. supporting block; 423. first hinge axis; 424. second hinge axis; 5. fixing bolt; 6. Collaborative control system; 61. Processor; 62. Acceleration sensor; 63. Displacement sensor. DETAILED DESCRIPTION

[0043] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with Figures 1-5 of the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, not all of them. Based on the described embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field are within the scope of protection of the present invention.

[0044] Example 1:

[0045] As shown in Figures 1-2 , the present invention provides a test model for simulating soil evolution during earthquakes on long-span bridges. The test model includes a shaking table 1, a long-span bridge model 2, a damping control device 3, a vibration mechanism 4, and a coordinated control system 6. Multiple positioning holes 11 are evenly distributed on the surface of the shaking table 1 to accommodate the fixed installation of long-span bridge models 2 of various sizes on the shaking table 1. A plurality of vibration mechanisms 4 are arranged around the vibration table 1. The vibration mechanism 4 includes a driving cylinder 41 and a transmission mechanism 42. The transmission mechanism 42 includes a support slot block 421 fixedly connected to the side wall of the vibration table 1. A support block 422 is connected to the support slot block 421 via 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 driving cylinder 41. The support block 422 can rotate along the support slot block 421 via the first hinge shaft and the second hinge shaft respectively; the driving cylinder 41 can adopt a driving cylinder, a driving electric steel or a driving oil cylinder, and each driving cylinder 41 adopts a separate frequency conversion control. The plurality of vibration mechanisms 4 cooperate to drive the vibration table 1 to vibrate along the spatial coordinates X / Y / Z, thereby simulating the non-uniform excitation of the soil during the earthquake through the vibration table 1, and realistically simulating the dynamic response of the structure of each pier base 21 of the long-span bridge, thereby improving the authenticity and accuracy of the experimental model.

[0046] The long-span bridge model 2 includes a bridge structure and multiple pier bases 21 arranged along its length. A connecting base plate 211 is provided at the bottom of each pier base 21. A damping control device 3 is fixedly connected to the bottom end of each pier base 21. The damping control device 3 is fixedly connected to a corresponding position on the vibration table 1. The damping control device 3 transmits the simulated vibration of the vibration table 1 to the long-span bridge model 2 through the damping control device 3.

[0047] As shown in Figure 3-4, 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 moving assembly 34 is vertically arranged in the cylinder body 321. The moving assembly 34 can move along its axial and radial directions, and a mounting top plate 33 is provided at the top of the moving assembly 34. Connecting holes 35 are respectively provided on the mounting base 31 and the mounting top plate 33. The connecting base 211 is fixedly connected to the mounting base 31 by fixing bolts 5, and the mounting base 31 is fixedly connected to the vibration table 1 by fixing bolts 5.

[0048] The interior of the cylinder 321 is divided into an upper chamber 323 and a lower chamber 324 by a partition plate 322. The upper chamber 323 contains magnetorheological fluid 310, and an axial hole 326 and a sealing plate 36 are respectively provided at the top and bottom centers of the upper chamber 323 to seal the axial hole. The movement assembly 34 includes a movable shaft 341, which extends through the upper chamber 323 and into the lower chamber 324. The movable shaft 341 passes through the centers of the two sets of sealing plates 36 and can move slightly up and down along the sealing plates 36. A mounting post 342 is provided in the middle of the movable shaft 341, within which a mounting cavity is provided. The mounting post 342 is located within the upper chamber 323. A first electromagnetic unit 37 is provided in the circumferential cylinder sidewalls of the upper chamber 323 and the circumferential sidewalls of the mounting post 342. When energized, the first electromagnetic unit 37 generates an electromagnetic field. The top end of the movable shaft 341 is fixedly connected to the mounting top plate 33, and the bottom end of the movable shaft 341 is provided with a support plate 343 located in the lower cavity 324. The second electromagnetic unit 38 is respectively provided in the circumference of the support plate 343 and the circumference of the bottom plate of the lower cavity 324. When the second electromagnetic unit 38 is energized, an electromagnetic field is generated, thereby forming a repulsive force between the support plate 343 and the bottom surface of the cylinder body 321, so that the moving component 34 is in a suspended state, reducing the friction during the movement process.

[0049] An anti-collision foam layer 325 is provided on the inner wall of the cylinder body 321 of the lower cavity 324 to prevent the displacement of the moving component 34 in the inner cavity of the cylinder body 321 from exceeding the limit.

[0050] A magnetic isolation layer 39 is attached to the side wall of the cylinder of the upper cavity 323 to prevent magnetic leakage in the cylinder 321 and improve the damping performance of the damping control device 3.

[0051] The test model also includes a collaborative control system 6, which includes a processor 61 and an acceleration sensor 62 and a displacement sensor 63 electrically connected to the processor. 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 plate 343; 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. The control module can adopt a single-chip microcomputer. Initial soil layer parameters are set according to the test requirements, and current drive is input. When the vibration table 1 vibrates at the set frequency, the vibration table 1 transmits the vibration to the damping control device 3, causing the oscillating component 34 to shift within the damping cylinder 32. The acceleration sensor 62 and the displacement sensor 63 respectively collect acceleration and displacement data information from the damping control device 3 and feed the data information back to the processor 61 for processing. After receiving the data, the processor 61 passes it through an adjustable bandpass filter. The bandpass range is selected and determined according to the physical properties of the soil. After signal amplification, the processor can combine historical data with current displacement and acceleration data to adjust the corresponding damping according to the set soil properties. The damping adjustment control converts the current drive into a magnetic field change. The change in the magnetic field of the environment in which the magnetorheological fluid is located is used to change the damping force and simulate the evolution of soil physical properties. The various coordinated control systems 6 coordinate control to realize the simulation of the seismic response of the bridge under earthquake site effects and multi-point non-uniform excitation. Finally, the dynamic response data of the long-span bridge during the earthquake is collected and the structural response of the long-span bridge is analyzed.

[0052] Example 2:

[0053] As shown in FIG5 , the present invention further discloses a test method for simulating the dynamic response of a test model, the test method comprising the following steps:

[0054] (1) The vibration table 1 is connected to a support frame (not shown in the figure) through multiple sets of vibration mechanisms 4 arranged circumferentially thereof; specifically, the outer ends of the driving cylinders 41 of the vibration mechanisms 4 are fixedly connected to the support frame respectively, so as to keep the vibration table 1 in a suspended state. By controlling the action frequencies of the multiple driving cylinders 41 respectively, the multiple sets of vibration mechanisms 4 cooperatively drive the vibration table 1 to vibrate along the spatial coordinates X / Y / Z. The vibration table 1 can simulate the non-uniform excitation of the soil during an earthquake, and realistically simulate the dynamic response of the structure of each pier base 21 of a large-span bridge.

[0055] (2) According to the size of the long-span bridge model 2 and the position of its corresponding pier base 21, the damping control device 3 with the same number as the pier base is fixedly installed on the corresponding position of the vibration table 1, and the long-span bridge model 2 is hoisted to the top of the damping control device 3 by a crane, and the pier base 21 is fixedly connected to the damping control device 3 by fixing bolts 5 to maintain the movement consistency of the damping control device 3 and the long-span bridge model 2.

[0056] (3) Based on the structural dimensions of the long-span bridge, the vibration table 1 is used to simulate the soil characteristics of the long-span bridge. The initial parameters of the soil layer are set according to the test requirements, and the vibration mechanism 4 is controlled to drive the vibration table 1 to vibrate at the required frequency, thereby improving the authenticity of the simulation of soil characteristics during the earthquake.

[0057] (4) When the vibration table 1 starts to simulate the changes of soil during an earthquake, the vibration table 1 vibrates along the spatial coordinates X / Y / Z and transmits the vibration to the damping control device 3, causing the moving component 34 of the damping control device 3 to shift laterally or / and longitudinally along the inner cavity of the shock-absorbing cylinder 32. The moving component 34 transmits the vibration to the long-span bridge model 2, thereby causing the long-span bridge model to undergo structural deformation during the vibration process, so as to facilitate the analysis of the impact of the changes in soil caused by the earthquake on the long-span bridge structure.

[0058] (5) System control between each collaborative control system 6, wherein the acceleration sensor 62 and the displacement sensor 63 can collect the displacement and acceleration data information of the moving component 34 in real time, and transmit the data information to the processor 61 for processing, and 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.

[0059] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A test model for simulating the evolution of long-span bridge seismic soil, characterized in that: The test model includes: Vibration table (1); A long-span bridge model (2), the long-span bridge model (2) comprising a bridge body and a plurality of pier bases (21) supporting the bridge body; A damping control device (3), the damping control device (3) comprising a plurality of groups fixedly connected to the bottom end of the pier base (21), the damping control device (3) being fixedly connected to the vibration table (1); A vibration mechanism (4), the vibration mechanism (4) comprising a plurality of groups arranged around the vibration table (1), the vibration mechanism (4) driving the vibration table (1) to vibrate along the spatial coordinates X / Y / Z directions; A collaborative control system (6), the collaborative control system (6) comprising a processor (61) respectively arranged in a 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 collecting acceleration and displacement data information of the damping control device (3), and feeding the data information back to the processor for processing.

2. The test model for simulating the evolution of long-span bridge soil under earthquake according to claim 1 is characterized in that: The damping control device (3) comprises a mounting base (31) and a vibration reduction cylinder (32) fixedly arranged on the mounting base; The vibration-damping cylinder (32) comprises a cylinder body (321), a moving assembly (34) is vertically arranged in the cylinder body (321), the moving assembly (34) can move along its axial direction and radial direction, and a mounting top plate (33) is arranged at the top end of the moving assembly (34).

3. The test model for simulating the evolution of long-span bridge soil under earthquake according to claim 2 is characterized in that: The inner cavity of the cylinder body (321) is divided into an upper cavity (323) and a lower cavity (324) by a partition plate (322); the upper cavity (323) contains magnetorheological fluid (310), and the top and bottom centers of the upper cavity (323) are respectively provided with an axial hole (326) and a sealing plate (36) for blocking the axial hole; The moving assembly (34) comprises a moving shaft (341), the moving shaft (341) passes through the upper cavity (323) and extends to the lower cavity (324), and a mounting column (342) is arranged in the middle of the moving shaft (341), a mounting cavity is arranged in the mounting column (342), and the mounting column (342) is located in the upper cavity (323); The top end of the movable shaft (341) is fixedly connected to the mounting top plate (33), and the bottom end of the movable shaft (341) is provided with a support plate (343) located in the lower cavity (324); A first electromagnetic unit (37) is provided in the circumferential cylinder side wall of the upper cavity (323) and the circumferential side wall of the mounting column (342), respectively. The first electromagnetic unit (37) generates an electromagnetic field when energized; Second electromagnetic units (38) are respectively arranged in a circumferential direction of the support plate (343) and a circumferential direction of the bottom plate of the lower cavity (324), and the second electromagnetic units (38) generate an electromagnetic field when energized.

4. The test model for simulating the evolution of long-span bridge soil under earthquake according to claim 3 is characterized in that: The processor (61) and the acceleration sensor (62) are arranged in the mounting column (342); and the displacement sensor (63) is arranged on the supporting plate (343).

5. The test model for simulating the evolution of long-span bridge seismic soil according to claim 4 is characterized in that: The processor (61) comprises a control module and an adjustable bandpass filter module, a signal amplification module and a current drive module connected to the control module.

6. The test model for simulating the evolution of long-span bridge seismic soil according to claim 1, characterized in that: The vibration mechanism (4) comprises a driving cylinder (41) and a transmission mechanism (42); The transmission mechanism (42) comprises a support slot block (421) fixedly connected to the side wall of the vibration table (1); a support block (422) is connected to the support slot block (421) via a vertically arranged first hinge shaft (423) and a horizontally arranged second hinge shaft (424); and the support block (422) is fixedly connected to the front end of the piston rod of the driving cylinder (41).

7. The test model for simulating the evolution of long-span bridge soil under earthquake according to claim 3 is characterized in that: The inner wall of the cylinder of the lower cavity (324) is provided with an anti-collision foam layer (325).

8. The test model for simulating the evolution of long-span bridge soil under earthquake according to claim 3 is characterized in that: A magnetic isolation layer (39) is attached to the cylinder side wall of the upper cavity (323).

9. The test model for simulating the evolution of long-span bridge soil during earthquake according to claim 1, characterized in that: A plurality of positioning holes (11) are evenly distributed on the plate surface of the vibration table (1).

10. A test method for simulating the dynamic response of a test model as claimed in any one of claims 1 to 9, characterized in that: The test method includes the following steps: Step 1: Connect the vibration table (1) to the support frame through multiple sets of vibration mechanisms (4) arranged in the circumferential direction thereof, and keep the vibration table (1) in a suspended state; Step 2: According to the size of the long-span bridge model (2) and the position of its corresponding pier base (21), the damping control devices (3) having the same number as the pier bases are fixedly installed at the corresponding positions of the vibration table (1), the long-span bridge model (2) is hoisted above the damping control devices (3) by a crane, and the pier base (21) is fixedly connected to the damping control devices (3) by fixing bolts (5); Step 3: Based on the structural dimensions of the long-span bridge, a vibration table (1) is used to simulate the soil characteristics of the long-span bridge, initial parameters of the soil layer are set according to test requirements, and a vibration mechanism (4) is controlled to drive the vibration table (1) to vibrate at a desired 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 moving component (34) of the damping control device (3) to be displaced laterally or / and longitudinally along the inner cavity of the damping cylinder (32); the moving component (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 information of the moving component (34), and transmit the data information to the processor (61) for processing. The data information is subjected to an adjustable bandpass filter, and the bandpass range is determined according to the physical properties of the soil. After signal amplification, the damping size is readjusted, and the damping force is further adjusted in real time through current drive to simulate the evolution process of the physical properties of the soil. The collaborative control systems (6) are coordinated to realize the simulation of the seismic response of the bridge under the earthquake site effect and multi-point non-uniform excitation. Finally, the dynamic response data of the long-span bridge during the earthquake is collected to facilitate the analysis of the structural response of the long-span bridge.

Images