Experimental platform for testing the effect of the resonant frequency of the corridor bridge on the hydraulic wave compensation platform

Abstract

This invention provides an experimental platform for testing the influence of a bridge resonant frequency on a hydraulic wave compensation platform. The platform comprises, from top to bottom, a bridge simulation device, a single-degree-of-freedom compensation platform, and a single-degree-of-freedom excitation platform, all mounted within an integrated mounting bracket. The single-degree-of-freedom compensation platform includes, from top to bottom, an upper platform, a short spring, and a compensation electric cylinder. The bridge simulation device includes a long spring and a mass block. The single-degree-of-freedom excitation platform includes a lower platform, an excitation electric cylinder, and a servo motor driver. This invention, by employing a structure combining a long spring and a mass block as a load, vertically mounts the single-degree-of-freedom compensation system to simulate the situation of a bridge being installed on a wave compensation platform. This helps solve the problem of difficulty in experimentally measuring the influence of a bridge on the wave compensation platform control system, simplifies the experimental test system structure, reduces system size, and lowers costs.

Description

Technical Field

[0001] This invention relates to the field of shipbuilding and marine engineering, and more specifically, to an experimental platform for testing the influence of the resonant frequency of a corridor bridge on a hydraulic wave compensation platform. Background Technology

[0002] Transshipment operations refer to the direct transfer of cargo between vessels, which can be carried out at anchorages, buoys, or wharves. Organizing transshipment operations at ports with water-to-water transshipment can reduce operational steps, lower transportation costs, and speed up delivery. Transshipment operations at anchorages and buoys can also effectively alleviate port congestion and improve port throughput capacity. Due to the differences in the form, scale, operating conditions, and sea areas of offshore wind power platforms, different requirements are placed on the load, specifications, movement methods, and compensation accuracy of offshore corridor bridges, necessitating various types of wave-compensated offshore corridor bridges.

[0003] A Chinese patent with publication number CN114560057A discloses a wave-compensated multimodal experimental system for offshore walkways and its operating method. The experimental system includes a lifting module, a rotation module, a balancing module, a pitch and telescopic module, a simulation platform, and a wave compensation control system. This invention, based on a scaled-down offshore walkway and a simulation platform, employs a modular structural design to obtain an experimental system for offshore walkways with four different modes. However, this experimental system suffers from difficulties in construction, high cost, and the scaled-down scheme cannot accurately simulate the resonant frequency of actual transshipment walkways.

[0004] A Chinese patent with publication number CN103245475B discloses a vertical earthquake simulation test bench based on fuzzy control, comprising a test bench frame, an earthquake simulation device, and a seismic isolation hydraulic device. Its features include: the test bench frame consisting of a support base and a support; the earthquake simulation device consisting of an earthquake simulation hydraulic cylinder and a servo proportional valve, with the earthquake simulation hydraulic cylinder mounted on the support base of the test bench frame; and the seismic isolation hydraulic device comprising an upper seismic isolation hydraulic cylinder and a lower seismic isolation hydraulic cylinder, with their piston rods facing each other and rigidly connected by a load hanger. The cylinder body of the lower seismic isolation hydraulic cylinder is connected to the piston rod of the earthquake simulation hydraulic cylinder, and the cylinder body of the upper seismic isolation hydraulic cylinder is rigidly connected to a connecting plate located on the upper part of the support. A first position sensor is connected to the piston rod of the earthquake simulation hydraulic cylinder, and a second position sensor is connected to the load hanger. However, this test bench still suffers from problems such as a complex hydraulic system, high cost, large size, and a long production cycle for the hydraulic cylinders.

[0005] A Chinese patent with publication number CN113884323A discloses a testing device and method for a marine wave compensation crane, belonging to the technical field of testing equipment. In the marine wave compensation crane testing device, a first drive assembly connects to a movable support in a second testing component on a base, controlling the movable support to slide along a first direction. A second drive assembly located on the movable support in the second testing component causes the crane mounting platform in a third testing component on the movable support to move along a second direction. However, this device is not suitable for testing the influence of the resonant frequency of a transshipment bridge on the control system of a hydraulic wave compensation platform.

[0006] The inventors believe that the existing experimental systems are complex and expensive. Therefore, they have developed an easy-to-install, low-cost, and small-sized experimental platform for investigating the influence of the low natural frequency of the transect bridge on the control system of the hydraulic wave compensation platform. Summary of the Invention

[0007] To address the shortcomings of existing technologies, the purpose of this invention is to provide an experimental platform for testing the influence of the resonant frequency of a covered bridge on a hydraulic wave compensation platform.

[0008] An experimental platform for testing the influence of a corridor bridge resonant frequency on a hydraulic wave compensation platform, according to the present invention, includes a corridor bridge simulation device, a single-degree-of-freedom compensation platform, and a single-degree-of-freedom excitation platform, which are installed sequentially from top to bottom within an integral mounting bracket. The integral mounting bracket serves as the mounting base and includes a vertically arranged platform sliding guide rail. Both the single-degree-of-freedom compensation platform and the single-degree-of-freedom excitation platform slide in a vertical direction with the platform sliding guide rail. The single-degree-of-freedom compensation platform includes an upper platform, a short spring, and a compensation electric cylinder, which are connected sequentially from top to bottom. A sliding rod is vertically installed on the top of the upper platform, and the corridor bridge simulation device is sleeved on the sliding rod. The corridor bridge simulation device includes a long spring and a mass block. The upper end of the long spring is fastened to the mass block, and the lower end of the long spring is fastened to the upper platform. The single-degree-of-freedom excitation platform includes a lower platform, an excitation electric cylinder, and a servo motor driver. The bottom of the lower platform is fastened to the output end of the excitation electric cylinder. Both the compensation electric cylinder and the excitation electric cylinder are connected to the servo motor driver.

[0009] Preferably, the mass block includes a basic mass block and a detachable mass block, and one or more of the detachable mass blocks are fastened to the basic mass block; a first linear bearing is installed at the center of the basic mass block, and the first linear bearing is sleeved on the slide rod and the two slide in a vertical direction.

[0010] Preferably, the top of the upper platform is provided with a boss, the lower end of the long spring is fastened to the boss of the upper platform, and the long spring is interference-fitted with the boss.

[0011] Preferably, the top of the short spring is interference-fitted with the bottom center of the upper platform, an electric cylinder spring connector is provided between the short spring and the compensating electric cylinder, and the bottom of the short spring is interference-fitted with the electric cylinder spring connector.

[0012] Preferably, each of the four corners of the upper platform is provided with a first platform mounting component, and the upper platform slides in a vertical direction with the platform sliding guide rail through the first platform mounting component.

[0013] Preferably, a second platform mounting component is provided at each of the four corners of the lower platform, and the lower platform slides in a vertical direction with the platform sliding guide rail through the second platform mounting component.

[0014] Preferably, the overall mounting bracket includes an aluminum profile frame, a bottom mounting platform, and a top mounting platform; the bottom mounting platform is securely mounted on the bottom of the aluminum profile frame, and the excitation electric cylinder is securely mounted on the bottom mounting platform; four platform sliding guide rails are securely mounted on the aluminum profile frame; and the top mounting platform is securely mounted on the top of the aluminum profile frame.

[0015] Preferably, the top mounting platform has a through hole at its center, a second linear bearing is mounted in the through hole, and the slide rod extends through the second linear bearing to the top of the top mounting platform.

[0016] Preferably, the single-degree-of-freedom compensation platform further includes a first position sensor, which is used to measure the position of the upper platform; the upper part of the first position sensor is connected to the upper platform through a first position sensor clamp, and the lower part of the first position sensor is connected to the aluminum profile frame through a first position sensor mounting component.

[0017] Preferably, the single-degree-of-freedom excitation platform further includes a second position sensor, which is used to measure the position of the lower platform; the upper part of the second position sensor is connected to the lower platform through a second position sensor clamp, and the lower part of the second position sensor is connected to the aluminum profile frame through a second position sensor mounting component.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. This invention uses a structure combining a long spring and a mass block to control its natural frequency within the range of 1-1.5Hz of the natural frequency of the bridge. This mass block is then used as a load and vertically installed on a single-degree-of-freedom compensation system to simulate the situation where the bridge is installed on a wave compensation platform. This helps to solve the problem of the difficulty in experimentally measuring the impact of the bridge on the wave compensation platform control system, simplifies the experimental test system structure, reduces system size, and lowers costs.

[0020] 2. This invention combines a short spring with a compensating electric cylinder, reducing the natural frequency of the compensating electric cylinder to be similar to that of a hydraulic cylinder. This achieves the goal of replacing hydraulic cylinders with electric cylinders in control system experiments, helping to solve the problems of overly complex supporting systems, high prices, and long delivery cycles when using hydraulic cylinders to build control system experimental platforms. It also helps to shorten the system construction cycle and reduce costs.

[0021] 3. This invention replaces the six-degree-of-freedom wave compensation platform with a single-degree-of-freedom compensation platform, and combines a bridge simulation device with the simulation of the control characteristics of the hydraulic cylinder by the electric cylinder, which helps to solve the problem of the difficulty in testing the impact of the transshipment bridge on the wave compensation system. Attached Figure Description

[0022] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0023] Figure 1 This is a schematic diagram of the overall structure of the experimental platform used in this invention to test the influence of the resonant frequency of the corridor bridge on the hydraulic wave compensation platform.

[0024] Figure 2 This is a front view of the experimental platform used in this invention to test the influence of the resonant frequency of the covered bridge on the hydraulic wave compensation platform.

[0025] Figure 3 This is a schematic diagram illustrating the structure of the bridge simulation device, which is the main feature of this invention.

[0026] Figure 4 This is a schematic diagram illustrating the structure of the single-degree-of-freedom compensation platform, which is the main feature of this invention.

[0027] Figure 5 This is a schematic diagram illustrating the structure of the single-degree-of-freedom excitation platform, which is the main feature of this invention.

[0028] Figure 6 This is a schematic diagram illustrating the overall mounting bracket structure of the present invention.

[0029] As shown in the figure:

[0030] Corridor bridge simulation device 1, long spring 11

[0031] First linear bearing 12 Basic mass block 13

[0032] Detachable mass block 14 Single-degree-of-freedom compensation platform 2

[0033] Upper platform 21, short spring 22

[0034] 23 Hexagonal nut; 24 Electric cylinder spring connector

[0035] Compensating electric cylinder 25 First position sensor fixture 26

[0036] First platform mounting component 27 First position sensor 28

[0037] First position sensor mounting part 29 Slide bar 210

[0038] Single-degree-of-freedom incentive platform 3, platform 31

[0039] Electric cylinder platform connector 32; Excitation electric cylinder 33

[0040] Servo motor driver 34 Second position sensor fixture 35

[0041] Second platform mounting component 36; Second position sensor 37

[0042] Second position sensor mounting component 38 Overall mounting bracket 4

[0043] Aluminum profile frame 41, bottom mounting platform 42

[0044] Platform sliding guide rail 43 Top mounting platform 44

[0045] Second linear bearing 45 Detailed Implementation

[0046] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0047] like Figure 1-6As shown, an experimental platform for testing the influence of the resonant frequency of a covered bridge on a hydraulic wave compensation platform according to the present invention includes a covered bridge simulation device 1, a single-degree-of-freedom compensation platform 2, and a single-degree-of-freedom excitation platform 3, which are installed sequentially from top to bottom within an integral mounting bracket 4. The integral mounting bracket 4 serves as the mounting base and includes a vertically arranged platform sliding guide rail 43. Both the single-degree-of-freedom compensation platform 2 and the single-degree-of-freedom excitation platform 3 slide in cooperation with the platform sliding guide rail 43 along the vertical direction. The single-degree-of-freedom compensation platform 2 includes an upper platform 21, a short spring 22, and a compensation spring 23 connected sequentially from top to bottom. The compensation electric cylinder 25 and the upper platform 21 are vertically mounted on the top of the slide rod 210. The corridor simulation device 1 is mounted on the slide rod 210. The corridor simulation device 1 includes a long spring 11 and a mass block. The upper end of the long spring 11 is fixedly connected to the mass block, and the lower end of the long spring 11 is fixedly connected to the upper platform 21. The single-degree-of-freedom excitation platform 3 includes a lower platform 31, an excitation electric cylinder 33, and a servo motor driver 34. The bottom of the lower platform 31 is fixedly connected to the output end of the excitation electric cylinder 33. Both the compensation electric cylinder 25 and the excitation electric cylinder 33 are connected to the servo motor driver 34.

[0048] This application provides a novel, easy-to-install, low-cost, and small-sized experimental platform to investigate the impact of the low natural frequency of a transshipment bridge on the control system of a hydraulic wave compensation platform. A long spring 11 and a mass block are combined to simulate a transshipment bridge with a resonant frequency of 1-1.5Hz at sea, and are installed as a load on a single-degree-of-freedom compensation platform 2. The natural frequency of the compensation electric cylinder 25 is lowered by combining it with a short spring 22, making the control characteristics of the compensation electric cylinder 25 similar to those of a hydraulic cylinder, thus achieving the replacement of the hydraulic cylinder in the control system with an electric cylinder.

[0049] The overall mounting bracket 4 includes an aluminum profile frame 41, a bottom mounting platform 42, and a top mounting platform 44. The bottom mounting platform 42 is securely mounted to the bottom of the aluminum profile frame 41, and the excitation electric cylinder 33 is securely mounted on the bottom mounting platform 42. Four platform sliding guide rails 43 are securely mounted on the aluminum profile frame 41. The top mounting platform 44 is securely mounted on the top of the aluminum profile frame 41. A through hole is provided in the center of the top mounting platform 44, and a second linear bearing 45 is installed in the through hole. The slide rod 210 extends through the second linear bearing 45 to the top of the top mounting platform 44.

[0050] The aluminum profile frame 41 is responsible for fixing and balancing the entire experimental platform, facilitating the installation of other parts. The bottom mounting platform 42 is fixed to the bottom of the aluminum profile frame 41 with bolts and serves as the mounting platform for the excitation electric cylinder 33. Four platform sliding guide rails 43 are fixed around the aluminum profile frame 41 with bolts, ensuring that the upper platform 21 and lower platform 31 can only move vertically up and down, preventing deflection. The top mounting platform 44 is fixed to the top of the aluminum profile frame 41 with bolts, and has a through hole in the center. A second linear bearing 45 is installed at the through hole to cooperate with the slide rod 210, restricting its vertical movement. The overall mounting bracket 4 is responsible for the structural installation, balance, and fixation of the entire experimental platform, as well as restricting platform movement.

[0051] The walkway simulation device 1 includes a long spring 11 and a mass block. The mass block includes a basic mass block 13 and detachable mass blocks 14, with one or more detachable mass blocks 14 securely mounted on the basic mass block 13. The detachable mass blocks 14 are connected to the basic mass block 13 by hexagonal bolts, allowing the mass to be increased or decreased according to experimental needs, thereby controlling the resonant frequency of the walkway simulation device to vary within the range of 1-1.5Hz, consistent with the resonant frequency range of actual offshore transshipment walkways. A first linear bearing 12 is installed at the center of the basic mass block 13, and the first linear bearing 12 is sleeved on a sliding rod 210, with the two slidingly engaged in the vertical direction, allowing for free vertical vibration.

[0052] The top of the upper platform 21 is provided with a boss, and the lower end of the long spring 11 is fastened to the boss of the upper platform 21 with an interference fit. Through the interference fit and the effect of structural gravity, the long spring 11 is fixed to the boss of the upper platform 21 at the bottom and fixed to the basic mass block 13 at the top. The long spring 11 does not directly contact the slide rod 210 and has no frictional force.

[0053] The slide bar 210 passes through the top mounting platform 44 via a second linear bearing 45, and is threaded to the upper platform 21 at the bottom, allowing it to move freely up and down with the upper platform 21. The bridge simulation device 1, passing through the slide bar 210, is vertically mounted on the upper platform 21 as a load. The slide bar 210 ensures that the bridge simulation device 1 moves only in the vertical direction, guaranteeing that the actual natural frequency of the bridge simulation device 1 is the same as the experimentally designed natural frequency. The bridge simulation device 1, through a proper combination of a long spring 11 and a mass block, is vertically mounted and fixed to the single-degree-of-freedom compensation platform 2 as a load, allowing it to oscillate freely in the vertical direction. This simulates the situation of a transshipment bridge mounted on a wave-compensated six-degree-of-freedom platform in a single degree of freedom.

[0054] Each of the four corners of the upper platform 21 is provided with a first platform mounting piece 27. The upper platform 21 slides vertically with the platform sliding guide rail 43 through the first platform mounting pieces 27 at each corner. The upper platform 21, through the engagement of the first platform mounting pieces 27 at each corner with the corresponding platform sliding guide rail 43, allows it to perform only a single degree of freedom of movement (up and down), while minimizing friction. This is a platform that requires good control to remain stationary during compensated motion. The first platform mounting pieces 27 can slide freely up and down on the platform sliding guide rail 43 and are fixed to the upper platform 21 by bolts.

[0055] The top of the short spring 22 is interference-fitted with the bottom center of the upper platform 21, serving to support the upper platform 21. An electric cylinder spring connector 24 is provided between the short spring 22 and the compensating electric cylinder 25. The bottom of the short spring 22 is interference-fitted with the electric cylinder spring connector 24, and the electric cylinder connector 24 is connected to the compensating electric cylinder 25 via a hexagonal nut 23, thus achieving a fixed connection between the short spring 22 and the compensating electric cylinder 25. The compensating electric cylinder 25 is securely mounted on the lower platform 31. The short spring 22 and the compensating electric cylinder 25 form a simulated hydraulic cylinder, with the short spring 22 installed between the compensating electric cylinder 25 and the upper platform 21.

[0056] The compensating electric cylinder 25 is driven by a servo motor driver 34. Generally, the natural frequency of an electric cylinder can reach 100Hz or even higher, exhibiting good control characteristics. However, the control characteristics of a hydraulic cylinder are poor, with a maximum natural frequency of only about 16Hz. By integrating the short spring 22 and the compensating electric cylinder 25 as a whole, and selecting an appropriate stiffness coefficient for the short spring 22 based on the load weight, the natural frequency of the compensating electric cylinder 25 can be limited to a range similar to that of a hydraulic cylinder. This simulates the control characteristics of a hydraulic cylinder, enabling the electric cylinder to replace the hydraulic cylinder in the control system experimental platform. This replacement significantly reduces the complexity of the experimental platform, as well as the construction period and cost.

[0057] The single-degree-of-freedom compensation platform 2 also includes a first position sensor 28, which is used to measure the position of the upper platform 21. The upper part of the first position sensor 28 is connected to the upper platform 21 through the first position sensor clamp 26, and the lower part of the first position sensor 28 is connected to the aluminum profile frame 41 through the first position sensor mounting part 29.

[0058] The movement of the upper platform 21 is measured by the first position sensor 28, enabling high-precision position measurement of the upper platform. The first position sensor 28 is preferably an LVDT position sensor. Its upper part is connected to the upper platform 21 via a first position sensor clamp 26, moving up and down with the upper platform 21. Its lower part is fixed to the aluminum profile frame 41 via a first position sensor mounting bracket 29, remaining stationary. The first position sensor clamp 26 is bolted to the upper platform 21 and simultaneously holds the upper part of the first position sensor 28. The first position sensor mounting bracket 29 is fixed to the aluminum profile frame 41 with hexagonal bolts and hinged to the lower part of the first position sensor 28. Depending on the position of the upper and lower parts, the LVDT position sensor generates a corresponding induced electromotive force, thereby determining the position of the upper platform 21. This allows for the measurement of the residual movement of the upper platform after compensation, and enables monitoring and recording of the compensation effect.

[0059] The connection between the lower platform 31 and the platform sliding guide rail 43 is similar to that of the upper platform 21. Each of the four corners of the lower platform 31 is equipped with a second platform mounting piece 36, which allows the lower platform 31 to slide vertically into the platform sliding guide rail 43. The four second platform connecting pieces 36 connect the lower platform 31, allowing it to move only vertically up and down. The electric cylinder platform connecting piece 32 is bolted to the lower platform 31 around its perimeter and fixed to the output end of the excitation electric cylinder 33 at its center with a nut, thus connecting the excitation electric cylinder 33 to the lower platform 31. The lower platform 31 serves as the excitation platform, supported by the excitation electric cylinder 33. The movement of the excitation electric cylinder 33 is directly transmitted to the lower platform 31, simulating a hydraulic cylinder mounted on the lower platform 31. The excitation electric cylinder 33 is bolted to the bottom mounting platform 42 and driven by a servo motor driver 34.

[0060] The single-degree-of-freedom excitation platform 3 also includes a second position sensor 37, which measures the position of the lower platform 31. The upper part of the second position sensor 37 is connected to the lower platform 31 via a second position sensor clamp 35, and the lower part of the second position sensor 37 is connected to the aluminum profile frame 41 via a second position sensor mounting bracket 38. The second position sensor 37 measures the excitation motion of the lower platform 31 as the input to the single-degree-of-freedom compensation platform 2 to control the simulated hydraulic cylinder. It can record the actual excitation motion curve and compare it with the ideal excitation motion curve. The installation and fixing of the second position sensor 37 is similar to that of the first position sensor 28. The lower half is fixed to the aluminum profile frame 41 via the second sensor mounting bracket 38, and the upper half is connected to the lower platform 31 via the second position sensor clamp 35.

[0061] This application employs a structure combining a long spring 11 and mass blocks. By rationally selecting the long spring 11 and a certain number of mass blocks, its natural frequency is controlled within the range of 1-1.5Hz, the natural frequency of the bridge, and used as a load. It is vertically installed on a single-degree-of-freedom compensation system to simulate the situation where a transshipment bridge is installed on a wave compensation platform. This solves the problem of difficulty in experimentally measuring the impact of the transshipment bridge on the wave compensation platform control system, achieving the advantages of easy installation, low cost, and small size for the experimental testing system.

[0062] This application combines a short spring 22 with a compensating electric cylinder 25. By rationally selecting the stiffness of the short spring 22 according to the load weight, the natural frequency of the compensating electric cylinder 25 after combining with the short spring 22 is reduced to be close to that of the hydraulic cylinder. This achieves the goal of replacing the hydraulic cylinder with an electric cylinder in the control system experiment. It solves the problems of the supporting system being too complicated, the hydraulic cylinder being expensive, and the delivery cycle being too long when using hydraulic cylinders to build a control system experimental platform. It achieves the effect of quickly building a hydraulic cylinder control system experimental platform in a shorter time period in a simple and low-cost manner.

[0063] This application replaces the six-degree-of-freedom wave compensation platform with a single-degree-of-freedom compensation platform. Combined with a bridge simulation device and the simulation of the control characteristics of the electric cylinder on the hydraulic cylinder, it solves the problem of the difficulty in testing the impact of the transshipment bridge on the wave compensation system. This application has the characteristics of simple structure, low cost, small size and short construction period.

[0064] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0065] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. An experimental platform for testing the influence of the resonant frequency of a covered bridge on a hydraulic wave compensation platform, characterized in that, It includes a bridge simulation device (1), a single-degree-of-freedom compensation platform (2), and a single-degree-of-freedom excitation platform (3) installed sequentially from top to bottom within the overall mounting bracket (4). The overall mounting bracket (4) serves as the mounting base and includes a vertically arranged platform sliding guide rail (43). The single-degree-of-freedom compensation platform (2) and the single-degree-of-freedom excitation platform (3) are both slidably engaged with the platform sliding guide rail (43) in the vertical direction. The single-degree-of-freedom compensation platform (2) includes an upper platform (21), a short spring (22) and a compensation electric cylinder (25) connected from top to bottom. A slide rod (210) is vertically installed on the top of the upper platform (21), and the corridor simulation device (1) is sleeved on the slide rod (210). The bridge simulation device (1) includes a long spring (11) and a mass block. The upper end of the long spring (11) is fastened to the mass block, and the lower end of the long spring (11) is fastened to the upper platform (21). The single-degree-of-freedom excitation platform (3) includes a lower platform (31), an excitation electric cylinder (33), and a servo motor driver (34). The bottom of the lower platform (31) is fastened to the output end of the excitation electric cylinder (33). Both the compensation electric cylinder (25) and the excitation electric cylinder (33) are connected to the servo motor driver (34); The mass block includes a basic mass block (13) and a detachable mass block (14), one or more of the detachable mass blocks (14) being fastened to the basic mass block (13); The center of the basic mass block (13) is equipped with a first linear bearing (12), which is sleeved on the slide rod (210) and the two slide together in the vertical direction.

2. The experimental platform for testing the influence of the resonant frequency of a covered bridge on a hydraulic wave compensation platform as described in claim 1, characterized in that, The upper platform (21) has a boss on its top, and the lower end of the long spring (11) is fastened to the boss of the upper platform (21), and the long spring (11) is interference-fitted with the boss.

3. The experimental platform for testing the influence of the resonant frequency of a covered bridge on a hydraulic wave compensation platform as described in claim 1, characterized in that, The top of the short spring (22) is interference-fitted with the bottom center of the upper platform (21), and an electric cylinder spring connector (24) is provided between the short spring (22) and the compensating electric cylinder (25). The bottom of the short spring (22) is interference-fitted with the electric cylinder spring connector (24).

4. The experimental platform for testing the influence of the resonant frequency of a covered bridge on a hydraulic wave compensation platform as described in claim 1, characterized in that, The upper platform (21) is provided with a first platform mounting component (27) at each of its four corners. The upper platform (21) slides in a vertical direction with the platform sliding guide rail (43) through the first platform mounting component (27).

5. The experimental platform for testing the influence of the resonant frequency of a covered bridge on a hydraulic wave compensation platform as described in claim 1, characterized in that, The lower platform (31) is provided with a second platform mounting component (36) at each of its four corners. The lower platform (31) slides in a vertical direction with the platform sliding guide rail (43) through the second platform mounting component (36).

6. The experimental platform for testing the influence of the resonant frequency of a covered bridge on a hydraulic wave compensation platform as described in claim 1, characterized in that, The overall mounting bracket (4) includes an aluminum profile frame (41), a bottom mounting platform (42), and a top mounting platform (44). The bottom mounting platform (42) is fastened to the bottom of the aluminum profile frame (41), and the excitation electric cylinder (33) is fastened to the bottom mounting platform (42); The four platform sliding rails (43) are fastened to the aluminum profile frame (41); The top mounting platform (44) is securely mounted on top of the aluminum profile frame (41).

7. The experimental platform for testing the influence of the resonant frequency of a covered bridge on a hydraulic wave compensation platform as described in claim 6, characterized in that, The top mounting platform (44) has a through hole at its center, and a second linear bearing (45) is installed in the through hole. The slide rod (210) extends through the second linear bearing (45) to the top mounting platform (44).

8. The experimental platform for testing the influence of the resonant frequency of a covered bridge on a hydraulic wave compensation platform as described in claim 6, characterized in that, The single-degree-of-freedom compensation platform (2) further includes a first position sensor (28), which is used to measure the position of the upper platform (21); The upper part of the first position sensor (28) is connected to the upper platform (21) through the first position sensor clamp (26), and the lower part of the first position sensor (28) is connected to the aluminum profile frame (41) through the first position sensor mounting part (29).

9. The experimental platform for testing the influence of the resonant frequency of a covered bridge on a hydraulic wave compensation platform as described in claim 6, characterized in that, The single-degree-of-freedom excitation platform (3) also includes a second position sensor (37), which is used to measure the position of the lower platform (31); The upper part of the second position sensor (37) is connected to the lower platform (31) through the second position sensor clamp (35), and the lower part of the second position sensor (37) is connected to the aluminum profile frame (41) through the second position sensor mounting part (38).

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