Damping test platform

Abstract

The present application belongs to the technical field of track damping test device, and particularly relates to a damping test platform. The damping test platform comprises: a single degree of freedom simulation test mechanism for simulating a first order vertical rigid body vibration mode shape corresponding to a first order natural frequency of a floating slab track; a four-point support plate simulation test mechanism for simulating high order rigid body vibration mode shapes, bending and torsion mode shapes in a higher frequency range of the floating slab track; a vibration sensing device arranged on the single degree of freedom simulation test mechanism and the four-point support plate simulation test mechanism for measuring and collecting force responses and acceleration responses; a bottom plate; the bottom plate is symmetrically provided with sliding grooves, the single degree of freedom simulation test mechanism and the four-point support plate simulation test mechanism are arranged side by side on the bottom plate and located between the symmetric sliding grooves; and a jacking and hoisting mechanism located on the bottom plate and in sliding fit connection with the sliding grooves for hoisting and transporting the test mechanism, installing a loading mechanism and adjusting test operation.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of track damping test device, and particularly relates to a damping test platform. BACKGROUND

[0002] Floating slab track damping technology is a common and excellent damping technology in the field of urban rail transit damping. In the field of rail transit damping, corresponding damping test devices and equipment are needed for floating slab track tests. Many tests are based on full-size floating slab tracks, which require large handling equipment to move the track slab and large loading equipment to excite the track slab to vibrate. There are problems such as difficulty in moving, high test cost, and large space occupation. In the specification documents such as “Standard for Construction Quality Acceptance of Steel Spring Floating Slab Track for Urban Rail Transit” (DG / TJ 08-2416-2023 J16935-2023) and some experienced rail vibration detection units in the industry, the track slab is simplified as a single-degree-of-freedom vibration system, and a single isolator is placed at the center of the concrete mass to form a single-degree-of-freedom mass-spring-damper system damping test device. The weight of the concrete mass is designed according to the weight of the track slab shared by the single isolator in the actual floating slab track. This single-degree-of-freedom system damping test device can not only simulate the vertical vibration characteristics of the track structure, but also reduce the volume and mass of the test device to facilitate equipment handling and debugging. However, in actual use, the concrete mass of the existing single-degree-of-freedom system damping test device is prone to shaking, causing test data errors due to the lack of lateral restraint. Patent document CN103149048A discloses a track vibration isolation multifunctional test platform based on magneto-rheological technology. In this test platform, an eccentric block type exciter connected with the track in a semi-rigid manner is used to simulate the external excitation force of the train wheel and rail, which does not match the actual situation of nonlinear contact between the train wheel and rail during operation. More importantly, this loading device and the loaded structure form a new vibration system, and the system natural frequency is no longer the natural frequency of the track system, making it difficult to accurately test the damping effect near the natural frequency of the track system, and the relevant test results are difficult to guide actual engineering design. Patent document CN108240894A discloses a track damping test device and track damping test equipment. This patent solves the problem of measuring errors caused by the coupling of the loading device and the loaded structure, which changes the natural frequency of the test device when simulating actual track vibration. However, this test device still has some limitations, such as the track damping test device vertically setting a spring part and a magneto-rheological damper between the simulated floating slab and the simulated lower slab. The spring part only moves up and down, realizing a single-degree-of-freedom vibration system. However, when testing the magneto-rheological damper or other damping elements with this device, the spring part used to support the simulated floating slab will provide excess support stiffness, causing test deviations and changing the natural frequency of the test device.In addition, the existing single degree of freedom test device simulates the first order vertical rigid body vibration mode corresponding to the first order natural frequency of the floating slab track, is mainly used for testing the vibration reduction performance of a single vibration isolator on the first order mode of the floating slab track, and cannot reflect other higher order rigid body vibration mode and bending and torsional mode of the floating slab track, and the test result cannot prove the vibration reduction performance on other higher order mode of the floating slab track. In addition, the thickness or cross-sectional form of the floating slab in different track lines will be different, that is, the weight of the slab shared by each vibration isolator will change or the natural frequency of the vibration system will change, however, the mass of the vibrator of the test device cannot be adjusted to reflect the change of the weight of the slab shared by each vibration isolator. Moreover, there are problems of single loading form, single detection product and difficult transportation. SUMMARY

[0003] The purpose of the present application is to solve the above problems, and provide a vibration reduction test platform.

[0004] In a first aspect, a vibration reduction test platform adopts the following technical scheme:

[0005] A vibration reduction test platform comprises:

[0006] A single degree of freedom simulation test mechanism is used for simulating the first order vertical rigid body vibration mode corresponding to the first order natural frequency of the floating slab track, and the total mass of the single degree of freedom vibrator is adjusted to adjust the natural frequency to correspond to the first order natural frequency of the actual track.

[0007] A four-point support plate simulation test mechanism is used for simulating the high order rigid body vibration mode, bending and torsional mode and other mode in the high frequency range of the floating slab track, and the total mass of the vibration plate is adjusted to adjust the vibration frequency to correspond to the high frequency vibration of the actual track.

[0008] A vibration sensing device is arranged on the single degree of freedom simulation test mechanism and the four-point support plate simulation test mechanism, and is used for measuring and collecting force response and acceleration response, and calculating the transfer function between the input and output of the vibration system, and analyzing the vibration characteristics and vibration reduction effect in each frequency band.

[0009] A bottom plate is provided with symmetrical grooves, and the single degree of freedom simulation test mechanism and the four-point support plate simulation test mechanism are arranged side by side on the bottom plate and located between the symmetrical grooves.

[0010] A jacking and hoisting mechanism is located on the bottom plate and is in sliding fit connection with the grooves, and is used for hoisting and transporting the test mechanism, installing the loading mechanism and adjusting the test operation.

[0011] Further, the single degree of freedom simulation test mechanism comprises a first base, a single degree of freedom oscillator, a first damping element, a first jack and a rigid limiting column;

[0012] The first base is fixedly connected with the bottom plate, a plurality of rigid limiting columns are vertically inserted and fixed on the first base, and the first damping element is arranged at the center position; the single degree of freedom oscillator is arranged above the first damping element, the single degree of freedom oscillator is provided with a through hole, and the single degree of freedom oscillator is vertically and slidingly sleeved with the rigid limiting column through the through hole; the jacks are symmetrically arranged on the two sides of the first damping element, the bottom of the jack is fixedly connected with the bottom plate, and the top of the jack abuts against the single degree of freedom oscillator, so as to stretch and upwardly lift the single degree of freedom oscillator.

[0013] Further, the single degree of freedom oscillator comprises a heavy oscillator and a plurality of light oscillators, the heavy oscillator is aligned and fixedly connected with the plurality of light oscillators in a stacked manner, and the total mass of the single degree of freedom oscillator is adjusted by adjusting the number of the light oscillators.

[0014] Further, the rigid limiting column comprises a ball spline screw structure, the ball spline screw structure comprises a spline shaft and a spline female, the bottom of the spline shaft is fixedly connected with the bottom plate, and the spline female is fixedly connected at the bottom of the heavy oscillator and slidingly sleeved with the spline shaft.

[0015] Further, the four-point support plate simulation test mechanism comprises a second base, a second damping element, a second jack and a vibration plate;

[0016] The second base is fixedly connected with the bottom plate, a plurality of second damping elements are arranged at the corners, and the vibration plate is arranged at the top of the plurality of second damping elements; the second jacks are symmetrically arranged on the second base, the bottom of the second jack is fixedly connected with the bottom plate, and the top of the second jack abuts against the vibration plate, so as to stretch and upwardly lift the vibration plate.

[0017] Further, the vibration plate comprises a heavy plate and a plurality of light plates, the heavy plate is aligned and fixedly connected with the plurality of light plates in a stacked manner, and the total mass of the vibration plate is adjusted by adjusting the number of the light plates.

[0018] Further, the vibration sensing device comprises a force sensor and an acceleration sensor; the force sensor is arranged at the bottom of the first damping element and the second damping element; the acceleration sensor is arranged at the top of the light oscillator and the light plate, and the first base and the second base; the force sensor is used for collecting force response in the test vibration system; and the acceleration sensor is used for collecting acceleration response in the test vibration system.

[0019] Further, the jacking and hoisting mechanism comprises a portal frame, a hoisting hook and a loading device; the cross beam of the portal frame is symmetrically provided with the hoisting hook, which is used for hoisting the test mechanism at a long distance; the cross beam of the portal frame is provided with the loading device, which is used for applying a load to the test mechanism; the bottom of the portal frame is in sliding fit with the sliding groove, and is fixedly connected with the bottom plate after sliding to a specified position.

[0020] Further, the loading device comprises one or more of a handheld force hammer, a drop hammer, a vibration exciter and an actuator.

[0021] Further, the loading device is the handheld force hammer, which vertically hammers the center of the top surface of the single-degree-of-freedom vibrator or the vibration plate, and an internal force sensor of the handheld force hammer measures the pulse excitation force input to the vibration system.

[0022] Alternatively, the loading device is the drop hammer, which freely impacts the center of the top surface of the single-degree-of-freedom vibrator or the vibration plate, and the size of each excitation force is controlled to be maintained at a required force value by controlling the height of the drop hammer.

[0023] Alternatively, the loading device is the vibration exciter, which applies a load downward, the excitation point is at the center of the top surface of the single-degree-of-freedom vibrator or the vibration plate, and a specific frequency or swept sine load or pulse excitation or white noise excitation is applied, and a force sensor is arranged at the head of the loading rod of the vibration exciter to measure the excitation force input to the vibration system.

[0024] Alternatively, the loading device is the actuator, which applies a load downward, the excitation point is at the center of the top surface of the single-degree-of-freedom vibrator or the vibration plate, and a specific frequency or swept sine load or pulse excitation or white noise excitation or wheel-rail force load spectrum is applied to excite the wheel-rail force, and a force sensor is arranged at the head of the actuator to measure the excitation force input to the vibration system.

[0025] The beneficial effects of the present application are as follows:

[0026] The vibration reduction test platform provided by the application realizes comprehensive simulation of the vibration characteristics of the floating slab track by integrating the single-degree-of-freedom simulation test mechanism and the four-point support plate simulation test mechanism, and can accurately test the vertical rigid body vibration mode corresponding to the first-order natural frequency and the rigid body vibration mode, the bending mode and the torsional mode of higher orders. The adjustable vibration mass of the platform enables the natural frequency to be flexibly matched with the vibration characteristics of the actual line track, thereby enhancing the adaptability and accuracy of the test. In addition, the vibration sensing device arranged on the platform can measure and record the force response and acceleration response of the vibration system in real time, and analyze the vibration characteristics and vibration reduction effect in different frequency bands by means of the transfer function, thereby providing a scientific basis for performance evaluation of the vibration reduction element. Meanwhile, the sliding groove structure on the bottom plate enables the layout of each test mechanism to be flexible, and the use of the jacking and hoisting mechanism significantly improves the installation efficiency and operation convenience of the test device. The overall platform is not only reasonable in structure but also comprehensive in function, and provides efficient and reliable test support for the vibration characteristic research and performance optimization of the vibration reduction element of the floating slab track. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 FIG. 1 is a structural schematic diagram of a vibration reduction test platform;

[0028] Figure 2 FIG. 2 is a structural schematic diagram of a single-degree-of-freedom simulation test mechanism;

[0029] Figure 3 FIG. 3 is a structural schematic diagram of a four-point support plate simulation test mechanism;

[0030] Figure 4 FIG. 4 is a structural schematic diagram of a rigid limiting rod.

[0031] FIG. 1 is a structural schematic diagram of a vibration reduction test platform; FIG. 2 is a structural schematic diagram of a single-degree-of-freedom simulation test mechanism; FIG. 3 is a structural schematic diagram of a four-point support plate simulation test mechanism; FIG. 4 is a structural schematic diagram of a rigid limiting rod; FIG. 5 is a structural schematic diagram of a vibration sensing device; and FIG. 6 is a structural schematic diagram of a jacking and hoisting mechanism. DETAILED DESCRIPTION

[0032] In order to make the purposes, technical solutions and advantages of the present application clearer, the following further describes the present application in conjunction with the accompanying drawings, and the described embodiments should not be regarded as limiting the present application. All other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0033] In the following description, reference is made to "some embodiments", which describe a subset of all possible embodiments, but it can be understood that "some embodiments" can be the same subset or different subsets of all possible embodiments, and can be combined with each other without conflict. Unless otherwise defined, all technical and scientific terms used in the embodiments of the present application have the same meaning as understood by those skilled in the art to which the embodiments of the present application belong. The terms used in the embodiments of the present application are only for the purpose of describing the embodiments of the present application and are not intended to limit the present application.

[0034] Those skilled in the art should understand that in the following description of the embodiments of the present application, the order of the serial numbers does not mean the order of execution, and some or all steps can be executed in parallel or in sequence, and the execution order of each process should be determined according to its function and inherent logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0035] The terms used in the embodiments of the present application are only for the purpose of describing the specific embodiments and are not intended to limit the present application. The singular forms "a" and "the" used in the embodiments of the present application and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise.

[0036] The present embodiment provides a vibration reduction test platform 1, as shown in Figure 1 The vibration reduction test platform 1 comprises:

[0037] A single-degree-of-freedom simulation test mechanism 10 is used to simulate the first-order rigid body vibration mode shape corresponding to the first-order natural frequency of the floating slab track, and the total mass of the single-degree-of-freedom vibrator 12 is adjusted to adjust the natural frequency to correspond to the first-order natural frequency of the actual line track;

[0038] A four-point support plate simulation test mechanism 20 is used to simulate high-order rigid body vibration mode shapes, bending and torsion mode shapes and the like in the high frequency range of the floating slab track, and the total mass of the vibration plate 24 is adjusted to adjust the vibration frequency to correspond to the high frequency vibration of the actual line track;

[0039] A vibration sensing device 30 is arranged on the single-degree-of-freedom simulation test mechanism 10 and the four-point support plate simulation test mechanism 20, and is used to measure and collect force response and acceleration response, and calculate the transfer function between the input and output of the vibration system, and analyze the vibration characteristics and vibration reduction effect in each frequency band;

[0040] The bottom plate 40 is provided with symmetrical grooves 41, and the single-degree-of-freedom simulation test mechanism 10 and the four-point support plate simulation test mechanism 20 are arranged side by side on the bottom plate 40 and located between the symmetrical grooves 41;

[0041] The jacking and lifting mechanism 50 is located on the bottom plate 40 and is in sliding fit connection with the grooves 41, and is used for lifting and transporting the test mechanism, installing the loading mechanism and adjusting the test operation.

[0042] The vibration reduction test platform 1 provided in the embodiment realizes accurate simulation of the floating slab track vibration characteristics and comprehensive testing of the vibration reduction performance through the organic combination of each component. The platform includes the single-degree-of-freedom simulation test mechanism 10 for simulating the first-order vertical rigid body vibration mode shape corresponding to the first-order natural frequency of the floating slab track. By adjusting the total mass of the single-degree-of-freedom oscillator 12, the natural frequency of the system can be changed to match the first-order natural frequency of the actual track, ensuring the accuracy of the test results. The mechanism provides necessary vertical elastic support and lateral stability through the damping elements and the rigid limiting column 15, ensuring the reliability of the vibration trajectory and dynamic response of the oscillator.

[0043] The four-point support plate simulation test mechanism 20 is used to simulate high-order rigid body vibration mode shapes in a higher frequency range, as well as the bending mode and torsional mode of the floating slab track. The vibration plate 24 as the core component changes the natural frequency of the high-order mode shape by adjusting the total mass of the vibration plate 24, so as to accurately restore the dynamics of the actual track.

[0044] The vibration sensing device 30 is installed on the single-degree-of-freedom simulation test mechanism 10 and the four-point support plate simulation test mechanism 20, and can measure and record the force response and acceleration response in the test system. By real-time acquisition and processing of these data, the sensing mechanism can calculate the transfer function between the input and output of the vibration system, further analyze the vibration characteristics and vibration reduction effect in different frequency bands, and provide a scientific basis for the optimization of the performance of the damping elements.

[0045] The bottom plate 40 as the support foundation of the platform is provided with symmetrical grooves 41, and the single-degree-of-freedom simulation test mechanism 10 and the four-point support plate simulation test mechanism 20 are arranged side by side on the bottom plate 40 and located between the grooves 41. The structure of the grooves 41 not only facilitates the position adjustment of the test mechanism, but also enhances the flexibility of the platform layout, meeting the needs of various test scenarios.

[0046] The lifting and hoisting mechanism 50 is located on the base plate 40 and is slidably connected to the slide groove 41. This mechanism can be used for hoisting and transporting the test device, as well as installing and adjusting the loading equipment. During the test, the lifting and hoisting mechanism 50 can precisely adjust the position and height of the test device to ensure the accuracy of the loading operation, while also facilitating the replacement of vibration damping components and the flexible adjustment of test conditions.

[0047] The vibration reduction test platform 1 in this embodiment, through the combination of a single-degree-of-freedom simulation test mechanism 10 and a four-point support plate simulation test mechanism 20, as well as the cooperation of a vibration sensing device 30, a base plate 40 and a lifting and hoisting mechanism 50, realizes the comprehensive simulation and testing of floating plate tracks from the first-order rigid body mode to higher-order modes. It has high precision, high efficiency and flexibility, and provides an important experimental tool for track vibration reduction technology research.

[0048] In some embodiments, such as Figure 2 As shown. The single-degree-of-freedom simulation test mechanism 10 includes a first base 11, a single-degree-of-freedom oscillator 12, a first damping element 13, a first jack 14, and rigid limiting columns 15. The first base 11 is fixedly connected to the base plate 40. Multiple rigid limiting columns 15 are vertically inserted and fixed on the first base 11, and the first damping element 13 is set at the center. The single-degree-of-freedom oscillator 12 is set above the first damping element 13. The single-degree-of-freedom oscillator 12 has a through hole and is vertically slidably fitted with the rigid limiting column 15 through the through hole. The jack is symmetrically arranged on both sides of the first damping element 13. The bottom of the jack is fixedly connected to the base plate 40, and the top of the jack abuts against the single-degree-of-freedom oscillator 12, which is used to extend and lift the single-degree-of-freedom oscillator 12 upward. More specifically, the first base 11 is a reinforced concrete base, square in shape, with dimensions of 1.5m long × 1.5m wide × 0.3m high, and is fixed to the base plate 40 by casting or bolting. Four smooth, rigid limiting posts 15 are vertically inserted into the four corners of the first base 11, their bottoms cast and fixed in the first base 11 and installed vertically. A first vibration damping element 13 is placed at the center of the first base 11, and two identical first jacks 14 are symmetrically arranged on both sides, with the bottom of each first jack 14 fixed to the first... On the base 11, the top can extend and lift heavy objects upwards; above the first damping element 13, a single-degree-of-freedom oscillator 12 is placed, which is 1.5m long and 1.5m wide, with through holes at the four corners to allow four rigid limiting posts 15 to pass through. The diameter of the through holes is slightly larger than that of the rigid limiting posts 15. During the normal vertical vibration of the single-degree-of-freedom oscillator 12, the friction with the rigid limiting posts 15 is kept as small as possible. When the applied load is eccentric or other situations cause the single-degree-of-freedom oscillator 12 to overturn, the rigid limiting posts 15 play a lateral protection role.

[0049] The first base 11, as the load-bearing foundation of the entire mechanism, is made of reinforced concrete, which has high strength and stability. The square shape and the size of 1.5 m x 1.5 m x 0.3 m of the base ensure its sufficient load-carrying capacity, and it is poured or bolted on the base plate 40 to provide a solid support platform. The four corners of the base are vertically inserted and fixed with four smooth rigid limiting columns 15, which are closely integrated with the base in structure to ensure their verticality, so as to provide reliable lateral restraint for the vertical movement of the single-degree-of-freedom oscillator 12.

[0050] The single-degree-of-freedom oscillator 12 is arranged above the first damping element 13, and its length and width are the same as those of the base. The through holes provided at the four corners are slightly larger than the diameter of the rigid limiting column 15, allowing the single-degree-of-freedom oscillator 12 to slide vertically along the rigid limiting column 15 while minimizing friction during movement. The rigid limiting column 15 not only limits the movement direction of the single-degree-of-freedom oscillator 12, but also prevents the oscillator from overturning under the application of eccentric load or other special conditions, thereby playing a role in lateral protection and improving the safety of the test and the reliability of the data.

[0051] The first damping element 13 is placed at the center of the first base 11 and is used to provide elastic support for the single-degree-of-freedom oscillator 12, so that the entire system has the dynamic characteristics of simulating the vertical rigid modal of the actual floating slab track during vibration. Through the elastic deformation of the damping element, the single-degree-of-freedom oscillator 12 can produce vibration response according to the set natural frequency.

[0052] The first jacks 14 arranged symmetrically on both sides are used to assist in adjusting the height of the single-degree-of-freedom oscillator 12. The bottom of the jack is fixed on the first base 11, and the top is freely extendable and directly contacts the single-degree-of-freedom oscillator 12. Through the lifting function of the jack, the test personnel can conveniently replace the first damping element 13 or adjust the initial position of the oscillator, while providing the necessary mechanical support for specific test conditions.

[0053] The single-degree-of-freedom simulation test mechanism 10 realizes the precise restoration of the first-order modal shape of the track through the close cooperation of the first base 11, the rigid limiting column 15, the first damping element 13, the first jack 14 and the single-degree-of-freedom oscillator 12, ensuring the authenticity of the system vibration response and the effectiveness of the test data.

[0054] In some embodiments, as Figure 2The single-degree-of-freedom oscillator 12 is made of reinforced concrete and includes a heavy oscillator 121 and a plurality of light oscillators 122. The heavy oscillator 121 is aligned and fixed with the plurality of light oscillators 122, and the total mass of the single-degree-of-freedom oscillator 12 is adjusted by adjusting the number of light oscillators 122. More specifically, the single-degree-of-freedom oscillator 12 includes two parts, a heavy oscillator 121 made of reinforced concrete with a size of 1.5 m long, 1.5 m wide, and 0.3 m thick, and the number of 1, and a plurality of light oscillators 122 made of reinforced concrete with a size of 1.5 m long, 1.5 m wide, and 0.05 m thick, and the number of several. The heavy oscillator 121 and the plurality of light oscillators 122 are aligned and fixed together by a pre-tightening bolt rod vertically penetrating all the oscillators, and the total mass of the single-degree-of-freedom oscillator 12 is adjusted by adjusting the number of light oscillators 122. The total mass of the single-degree-of-freedom oscillator 12 is about 2 t and can be adjusted.

[0055] The single-degree-of-freedom oscillator 12 is made of reinforced concrete and includes a heavy oscillator 121 and a plurality of light oscillators 122. The heavy oscillator 121 is aligned and fixed with the plurality of light oscillators 122, and the total mass of the single-degree-of-freedom oscillator 12 is adjusted by adjusting the number of light oscillators 122. More specifically, the single-degree-of-freedom oscillator 12 includes two parts, a heavy oscillator 121 made of reinforced concrete with a size of 1.5 m long, 1.5 m wide, and 0.3 m thick, and the number of 1, and a plurality of light oscillators 122 made of reinforced concrete with a size of 1.5 m long, 1.5 m wide, and 0.05 m thick, and the number of several. The heavy oscillator 121 and the plurality of light oscillators 122 are aligned and fixed together by a pre-tightening bolt rod vertically penetrating all the oscillators, and the total mass of the single-degree-of-freedom oscillator 12 is adjusted by adjusting the number of light oscillators 122. The total mass of the single-degree-of-freedom oscillator 12 is about 2 t and can be adjusted.

[0056] By adjusting the number of light oscillators 122, the total mass of the single-degree-of-freedom oscillator 12 can be flexibly changed, thereby adjusting the natural frequency of the vibration system to match the natural frequency of the first-order mode of the actual floating slab track. For example, by increasing or decreasing the number of light oscillators 122, the total mass of the oscillator can be accurately changed without changing other parameters of the system, making the system more adaptable and accurate in testing. Not only does it meet the vibration characteristic simulation needs of various track conditions, but it also reduces the risk of inaccurate test results caused by frequency errors.

[0057] During the vibration test, the single-degree-of-freedom oscillator 12 serves as the main vibration element, and its total mass directly affects the dynamics of the system. When the oscillator is excited by external force, its vibration characteristics are determined by the total mass of the oscillator, the elastic stiffness of the damping element, and the damping characteristics. By adjusting the number of light oscillators 122, the tester can conveniently control the mass distribution of the oscillator to match the vibration frequency characteristics of the target track, thereby effectively reproducing the vibration mode of the track under actual operating conditions.

[0058] In some embodiments, as Figure 4 The rigid limiting column 15 comprises a ball screw structure, which includes a spline shaft 151 and a spline nut 152. The spline shaft 151 is fixedly connected to the bottom plate 40, and the spline nut 152 is fixedly connected to the bottom of the single-degree-of-freedom vibrator 12. More specifically, the bottom of the spline shaft 151 is cast fixedly in the first base 11 and ensures the perpendicularity, and the spline nut 152 is cast fixedly or bolted fixedly in the heavy vibrator 121 of the single-degree-of-freedom vibrator 12. The spline nut 152 can slide along the spline shaft 151 in a straight line, with small friction and small gap, so as to ensure the smooth vertical vibration of the single-degree-of-freedom vibrator 12, and the vertical friction and lateral sway problems can be ignored.

[0059] The ball screw structure is composed of two parts, the spline shaft 151 and the spline nut 152. The bottom of the spline shaft 151 is cast fixedly in the first base 11 and is strictly controlled in perpendicularity to ensure its stability and accurate positioning in the system. The spline nut 152 is cast fixedly or bolted fixedly in the heavy vibrator 121 of the single-degree-of-freedom vibrator 12, forming an integrated connection with the overall structure of the vibrator. This structural design ensures that the vibrator can slide accurately in a straight line along the spline shaft 151 during vertical movement.

[0060] The spline shaft 151 and the spline nut 152 are in sliding fit through ball transmission. The ball transmission design features small friction and stable movement, effectively reducing the energy loss of the vibrator during vertical movement and reducing the test error caused by friction. In addition, the gap between the spline shaft 151 and the spline nut 152 is precisely controlled to ensure that it is small enough to reduce lateral sway, thereby improving the stability and data accuracy of the test system. The straight-line sliding motion of the spline nut 152 makes the vertical vibration of the vibrator more stable, avoiding the possible jamming or uneven damping in traditional limiting devices.

[0061] An important role of this structure is to provide necessary constraints to prevent the vibrator from producing lateral displacement or overturning when the single-degree-of-freedom vibrator 12 is subjected to vertical excitation. When the vibrator has eccentric moment due to the applied load, the mechanical fit between the spline shaft 151 and the spline nut 152 can provide lateral support in time to ensure that the vibrator can still maintain stable vibration in the vertical direction, thereby improving the anti-interference ability of the system and the safety of the test.

[0062] The application of the ball screw structure significantly optimizes the motion characteristics of the single-degree-of-freedom vibrator 12, ensuring the vertical vibration accuracy of the vibrator and effectively suppressing the lateral sway problem, thereby providing a stable and reliable operating environment for the dynamic response analysis of the system.

[0063] In some embodiments, as Figure 3The four-point support plate simulation test mechanism 20 includes a second base 21, a second damping element 22, a second jack 23, and a vibration plate 24. The second base 21 is fixedly connected with the bottom plate 40, and a plurality of second damping elements 22 are arranged at the corners of the second base 21. The top of the plurality of second damping elements 22 is provided with the vibration plate 24. The second base 21 is symmetrically provided with the second jacks 23. The bottom of the second jack 23 is fixedly connected with the bottom plate 40, and the top of the second jack 23 is in abutment with the vibration plate 24, so as to be telescopic and upwardly lift the vibration plate 24. More specifically, the second base 21 is made of concrete and has a plate shape with a size of 3m*3m*0.3m. The second base 21 is fixedly poured or bolted on the bottom plate 40. Four second damping elements 22 are symmetrically arranged at the four corners of the second base 21. Four second jacks 23 with the same performance are symmetrically arranged at the four edges of the second base 21. The bottom of the second jack 23 is fixed on the second base 21, and the top of the second jack 23 can be telescopic and upwardly lift the heavy object. The vibration plate 24 is arranged above the second damping element 22.

[0064] The second base 21 is used as the support base of the whole test mechanism and is made of concrete with a size of 3m*3m*0.3m, so as to ensure sufficient rigidity and stability. The second base 21 is fixedly poured or bolted on the bottom plate 40, so as to provide a solid support platform for the whole mechanism and provide a basis for the arrangement of the damping element and the jack. Four second damping elements 22 are symmetrically arranged at the four corners of the second base 21. The damping elements are located between the vibration plate 24 and the base, so as to provide elastic support for the vibration plate 24 and simulate the characteristics of the vibration isolator in the floating slab track.

[0065] The second damping element 22 is used as a key component and provides damping and stiffness support for the vibration of the vibration plate 24 through elastic deformation. The position and performance parameters of the second damping element 22 are carefully designed, so as to effectively restore the dynamic characteristics of the floating slab track under high-order rigid modal, bending modal and torsional modal, so as to realize the real reproduction of the vibration behavior.

[0066] Four second jacks 23 with the same performance are symmetrically arranged at the four edges of the second base 21. The bottom of the second jack 23 is fixed on the second base 21, and the top of the second jack 23 can be telescopic and in contact with the vibration plate 24. In the actual test, the jack is mainly used for lifting operation of the vibration plate 24. By adjusting the telescopic amount of the jack, the test personnel can flexibly replace the second damping element 22 or adjust the initial position of the vibration plate 24 to adapt to different test conditions or boundary parameters. The design of the jack further improves the convenience and operation efficiency of the test.

[0067] The vibrating plate 24, as the core component simulating the floating slab track structure, is placed on top of the second damping element 22. Its vibration behavior is influenced by both the loading force and boundary conditions. The vibration response corresponding to the target vibration mode is adjusted by modifying the total mass of the vibrating plate 24. The elastic support provided by the second damping element 22 enables the vibrating plate 24 to reflect the complex modal characteristics of the track system under dynamic conditions, including higher-order rigid body modes, bending modes, and torsional modes.

[0068] The four-point support plate simulation test mechanism 20, through its reasonable structural layout and functional coordination of various components, can realistically reproduce the high-order modal vibration characteristics of the floating plate track, providing a reliable test platform for track vibration research under different working conditions. Its rigid base and elastic support system ensure the stability of the test, the lifting function significantly improves the ease of operation, and the high adaptability of the vibration plate 24 allows the mechanism to be flexibly adjusted to meet different test requirements.

[0069] In some embodiments, such as Figure 3 As shown. The vibrating plate 24 includes a heavy plate 241 and multiple light plates 242. The heavy plate 241 and the multiple light plates 242 are stacked, aligned, and fastened together. The total mass of the vibrating plate 24 is adjusted by changing the number of light plates 242. More specifically, the vibrating plate 24 comprises two parts: a single heavy plate 241 made of reinforced concrete with dimensions of 3m long × 3m wide × 0.3m thick, and several light plates 242 made of reinforced concrete with dimensions of 3m long × 3m wide × 0.05m thick. The heavy plate 241 and the several light plates 242 are stacked and aligned together, and pre-tightened bolts are used to vertically penetrate all the plates to form a whole. The total mass of the vibrating plate 24 is adjusted by changing the number of light plates 242.

[0070] The vibrating plate 24 consists of two parts: a heavy plate 241 made of reinforced concrete and several light plates 242. The heavy plate 241, as the main body of the vibrating plate 24, has dimensions of 3m long × 3m wide × 0.3m thick, providing the foundation's mass inertia and rigid support. The light plates 242 have the same length and width dimensions, but are only 0.05m thick. Their design purpose is to allow for flexible adjustment of the total mass of the vibrating plate 24 through modular assembly. All the light plates 242 are stacked together with the heavy plate 241 and connected by pre-tightened bolts in the vertical direction to form a whole.

[0071] In actual tests, the total mass of the vibrating plate 24 can be flexibly changed by adjusting the number of lightweight plates 242. This adjustment method can precisely match the design requirements of different floating plate track systems. For example, the mass of the vibrating plate 24 can be adapted to achieve realistic dynamic characteristic reproduction based on the specific working conditions of the track system or the natural frequency of the target mode. This mass adjustment mechanism provides high flexibility for simulating higher-order rigid body modes, bending modes, and torsional modes, while ensuring that the dynamic response of the vibrating plate 24 under loaded forces is consistent with the actual track conditions.

[0072] The pre-tightened bolts, through their vertical penetration and fastening of the heavy plate 241 and the light plate 242, ensure the stability and consistency of the overall structure of the vibrating plate 24. The bolt pre-tightening force is sufficient to eliminate relative displacement or loosening between the plates, allowing the vibrating plate 24 to participate in vibration as a complete rigid body under dynamic excitation. Furthermore, due to the precise alignment and tight connection between the light plate 242 and the heavy plate 241, the center of gravity and mass distribution of the vibrating plate 24 remain uniform, further improving the reliability of the test data.

[0073] In some embodiments, such as Figure 1 , 2 As shown in Figure 3, the vibration sensing device 30 includes a force sensor 31 and an acceleration sensor 32; the force sensor 31 is disposed at the bottom of the first damping element 13 and the second damping element 22; the acceleration sensor 32 is disposed at the top of the light vibrator 122 and the light plate 242, as well as at the first base 11 and the second base 21; the force sensor 31 is used to collect the force response in the test vibration system; the acceleration sensor 32 is used to collect the acceleration response in the test vibration system. More specifically, the single-degree-of-freedom oscillator 12 or the top center of the vibrating plate 24 is excited using various excitation methods. An accelerometer 32 is used to measure the vibration acceleration response of the single-degree-of-freedom oscillator 12, the vibrating plate 24, the first base 11, and the second base 21. A force sensor 31 is used to measure the force response transmitted to the first base 11 or the second base 21 via the first damping element 13 or the second damping element 22. The transfer function between the input and output of the vibration system is calculated, the vibration characteristics and damping effect in each frequency band are analyzed, the vibration acceleration transmission loss of the upper and lower structures of the first damping element 13 and the second damping element 22 is calculated to evaluate the damping performance, the vibration acceleration response or force response of the first base 11 or the second base 21 without damping elements or with different damping elements is calculated, and the damping performance between different damping elements is compared.

[0074] Force sensor 31 is arranged at the bottom of the first damping element 13 and the second damping element 22 to measure the force response of the vibration load transmitted through the damping element to the first base 11 or the second base 21 in real time. By collecting these force response data, the mechanical performance of the damping element under different working conditions can be intuitively understood, such as the magnitude of the transmitted force and its variation law.

[0075] The acceleration sensors 32 are distributed on the top of the light mass 122 of the single degree of freedom mass 12, the top of the light plate 242 of the vibration plate 24, and the first base 11 and the second base 21, for measuring the vibration acceleration response of these key structural components. In the test, by applying various forms of excitation (such as hammering, actuator loading, etc.) to the top center of the single degree of freedom mass 12 or the vibration plate 24, the acceleration sensors 32 can record the dynamic acceleration characteristics of the test system under excitation, thereby capturing the response characteristics of the vibration system in different frequency bands.

[0076] Combined with the data of the force sensors 31 and the acceleration sensors 32, the transfer function between the input (loading force) and the output (vibration response) of the vibration system can be further calculated. This transfer function reflects the vibration characteristics of the system at different frequencies, providing quantitative basis for the test personnel to analyze the modal characteristics, stiffness distribution and damping performance of the system.

[0077] The vibration sensing device 30 also supports the evaluation of the performance of the damping elements. By calculating the transmission loss of the upper and lower structure vibration accelerations of the first damping element 13 and the second damping element 22, the damping effect of the damping elements can be quantified. For example, by comparing the acceleration differences of the upper and lower structures in different frequency bands, the vibration isolation ability of the damping elements can be intuitively evaluated. In addition, by comparing the base vibration acceleration responses or force responses of different damping elements under the same working conditions, the test personnel can make a comprehensive comparison of the performance of different damping elements.

[0078] The vibration sensing device 30 realizes the comprehensive analysis of the dynamic characteristics of the system through the multi-point arrangement and accurate measurement of the force sensors 31 and the acceleration sensors 32, and provides key data support for the performance evaluation and optimization of the damping elements.

[0079] In some embodiments, as shown in Figure 1 The jacking and lifting mechanism 50 includes a portal frame 51, a lifting hook 52, and a loading device 53. The lifting hooks 52 are symmetrically arranged on the cross beams of the portal frame 51 and are used for long-distance lifting of the test mechanism. The loading device 53 is arranged on the cross beams of the portal frame 51 and is used for applying load to the test mechanism. The bottom of the portal frame 51 is in sliding fit with the sliding chute 41 and is fixedly connected with the bottom plate 40 after sliding to the specified position.

[0080] The portal frame 51 is the core structure of the lifting and hoisting mechanism 50. It consists of crossbeams and supporting columns, and its width and height are designed to cover the range of the single-degree-of-freedom simulation test mechanism 10 and the four-point support plate simulation test mechanism 20, while ensuring sufficient rigidity and stability. The bottom of the portal frame 51 engages with a sliding groove 41 on the base plate 40 via pulleys, allowing the frame to slide smoothly along the groove 41. During test preparation or adjustment, the portal frame 51 can slide to the target test position and is securely connected to the base plate 40 via a fixing device, thereby ensuring the accuracy and safety of the hoisting and loading operations.

[0081] The portal frame 51 has symmetrically arranged lifting hooks 52 on its crossbeams for long-distance lifting of the test mechanism. When the test device needs to be moved or repositioned, the lifting hooks 52, in conjunction with steel ropes and pulleys, can lift the test mechanism from the ground and move it smoothly to the designated location. This structure effectively reduces the complexity and safety risks of manual handling, while improving the efficiency of test preparation.

[0082] The loading device 53 is mounted on the crossbeam of the portal frame 51 and is used to apply various forms of loading forces to the test mechanism. The loading device 53 can include different types such as a hammer, drop hammer, vibrator, or actuator, with the appropriate loading form selected according to the test requirements. The loading point is typically located at the center of the single-degree-of-freedom oscillator 12 or the vibration plate 24. A load of a specific frequency, amplitude, or waveform, such as pulse excitation or sinusoidal loading, is applied through the loading device 53 to excite the target vibration mode of the test mechanism. The installation position of the loading device 53 can be adjusted by sliding the portal frame 51 to achieve compatibility with different test mechanisms.

[0083] Through the coordinated action of the portal frame 51, lifting hook 52, and loading device 53, the jacking and hoisting mechanism 50 not only completes the hoisting and transportation of the test mechanism but also provides a stable loading platform, effectively reducing potential interference with test data during loading. Its flexible sliding design improves site adaptability, supports operational needs under various test mechanisms and conditions, and provides high-precision operational support for the dynamic loading of the test system, making it an important auxiliary device for the entire test platform.

[0084] In some embodiments, such as Figure 1 As shown. The loading device 53 includes one or more of a handheld hammer, a drop hammer, a vibrator, and an actuator. More specifically, these loading devices 53 or excitation methods avoid coupling with the test mechanism, do not change the set vibration frequency of the test mechanism, and these loading devices 53 are mounted on the portal frame 51 and can move with it to load both single-degree-of-freedom test mechanisms and four-point support plate test mechanisms.

[0085] In some embodiments, the loading device 53 is a handheld force hammer, which vertically hammers the center of the top surface of the single-degree-of-freedom vibrator 12 or the vibration plate 24, and the internal force sensor 31 in the handheld force hammer measures the pulse excitation force input to the vibration system;

[0086] Alternatively, the loading device 53 is a drop hammer, which freely impacts the center of the top surface of the single-degree-of-freedom vibrator 12 or the vibration plate 24, and the size of the excitation force is controlled by controlling the height of the drop hammer to maintain the required force value;

[0087] Alternatively, the loading device 53 is an exciter, which applies a load downward, and the excitation point is at the center of the top surface of the single-degree-of-freedom vibrator 12 or the vibration plate 24. The exciter applies a specific frequency or sweep sine load, or pulse excitation or white noise excitation. The head of the exciter loading rod is provided with a force sensor 31 to measure the excitation force input to the vibration system.

[0088] Alternatively, the loading device 53 is an actuator, which applies a load downward, and the excitation point is at the center of the top surface of the single-degree-of-freedom vibrator 12 or the vibration plate 24. The actuator applies a specific frequency or sweep sine load, or pulse excitation or white noise excitation, or a wheel-rail force load spectrum to apply a wheel-rail force excitation. The head of the actuator is provided with a force sensor 31 to measure the excitation force input to the vibration system.

[0089] The loading device 53 provides flexible and accurate loading functions for the test mechanism through various excitation modes to meet different needs of track vibration characteristic research, while avoiding coupling effects in the loading process, thereby ensuring that the dynamic characteristics of the test system remain unchanged.

[0090] When the loading device 53 is a handheld force hammer, the operator uses the force hammer to vertically hammer the center of the top surface of the single-degree-of-freedom vibrator 12 or the vibration plate 24, applying a short-time pulse excitation. The force hammer is internally provided with a force sensor 31, which can measure the pulse excitation force input to the vibration system in real time, ensuring that the amplitude and direction of the loading force meet the test requirements. This excitation mode is simple and efficient, and is particularly suitable for studying the transient vibration response of the system in the low frequency band.

[0091] When the loading device 53 is a drop hammer, the drop hammer freely falls through a release mechanism to impact the center of the top surface of the single-degree-of-freedom vibrator 12 or the vibration plate 24, and the excitation force applied is determined by the height and weight of the drop hammer. The non-contact characteristics of the drop hammer loading mode effectively avoid mechanical coupling with the test mechanism, ensuring that the natural frequency of the test system is not affected.

[0092] When the loading device 53 is an exciter, the exciter applies a load downward through a loading rod, and the excitation point is arranged at the center of the top surface of the single-degree-of-freedom vibrator 12 or the vibration plate 24. The exciter can apply a specific frequency, a swept-sine load or a pulse excitation or a white noise excitation, so as to excite the vibration response of the test mechanism at different frequency bands. The force sensor 31 arranged at the head of the loading rod of the exciter can record the dynamic force signal input to the vibration system in real time, and ensure the accuracy of the loading process and the reliability of the data.

[0093] When the loading device 53 is an actuator, the actuator can simulate more complex dynamic loading conditions, such as applying a wheel-rail force load spectrum to reproduce the track vibration characteristics under real working conditions. The actuator can apply a specific frequency, a swept-sine load or a pulse excitation or a white noise excitation or directly apply a wheel-rail force load spectrum, and the loading point is also located at the center of the top surface of the single-degree-of-freedom vibrator 12 or the vibration plate 24. The loading amplitude of the actuator is larger, and is suitable for high-strength dynamic test requirements, and the force sensor 31 arranged at the head of the actuator ensures the accurate measurement of the loading signal.

[0094] No matter which loading device 53 is used, these excitation modes are installed on the portal frame 51, and the sliding design of the frame realizes the compatible loading of the single-degree-of-freedom test mechanism and the four-point supporting plate test mechanism. The non-contact design of the loading device 53 and the test mechanism avoids the coupling effect, ensures that the natural frequency of the test mechanism is not disturbed during the loading process, and thus guarantees the accuracy and reliability of the test results.

[0095] The above merely describes the specific embodiments of the present application, but the protection scope of the present application is not limited to this. Any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, and all of them should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A vibration reduction test platform, characterized by, The damping test platform comprises: A single degree of freedom simulation test mechanism, which comprises a first base, a single degree of freedom oscillator, a first damping element, a first jack and a rigid limiting column; the first base is fixedly connected with the bottom plate, a plurality of rigid limiting columns are vertically inserted and fixed on the first base, and the first damping element is arranged at the center position; the single degree of freedom oscillator is arranged above the first damping element, the single degree of freedom oscillator is provided with a through hole, and the single degree of freedom oscillator is vertically and slidingly sleeved with the rigid limiting column through the through hole; the jacks are symmetrically arranged on the two sides of the first damping element, the bottom of the jack is fixedly connected with the bottom plate, and the top of the jack is abutted with the single degree of freedom oscillator, so as to stretch and upwardly lift the single degree of freedom oscillator; the single degree of freedom oscillator comprises a heavy oscillator and a plurality of light oscillators, the heavy oscillator is aligned and fixedly connected with the plurality of light oscillators, and the total mass of the single degree of freedom oscillator is adjusted by adjusting the number of light oscillators; A four-point support plate simulation test mechanism, which comprises a second base, a second damping element, a second jack and a vibration plate; the second base is fixedly connected with the bottom plate, a plurality of second damping elements are arranged at the corners, and the vibration plate is arranged at the top of the plurality of second damping elements; the second jacks are symmetrically arranged on the second base, the bottom of the second jack is fixedly connected with the bottom plate, and the top of the second jack is abutted with the vibration plate, so as to stretch and upwardly lift the vibration plate; A vibration sensing device arranged on the single degree of freedom simulation test mechanism and the four-point support plate simulation test mechanism, which is used for measuring and collecting force response and acceleration response, and calculating the transfer function between the input and output of the vibration system, and analyzing the vibration characteristics and damping effect in each frequency band; A bottom plate; the bottom plate is symmetrically provided with a sliding groove, the single degree of freedom simulation test mechanism and the four-point support plate simulation test mechanism are arranged side by side on the bottom plate and located between the symmetric sliding grooves; A lifting and hoisting mechanism located on the bottom plate and slidingly connected with the sliding groove, which is used for lifting, transporting the test mechanism, installing the loading mechanism and adjusting the test operation.

2. The vibration test platform according to claim 1, wherein The rigid limiting column comprises a ball screw structure, the ball screw structure comprises a spline shaft and a spline female, the bottom of the spline shaft is fixedly connected with the bottom plate, and the spline female is fixedly connected with the bottom of the heavy oscillator and slidingly sleeved with the spline shaft.

3. The vibration test platform of claim 1, wherein The vibration plate comprises a heavy plate and a plurality of light plates, the heavy plate is aligned and fixedly connected with the plurality of light plates, and the total mass of the vibration plate is adjusted by adjusting the number of light plates.

4. The vibration test platform of claim 1, wherein The vibration sensing device comprises a force sensor and an acceleration sensor; the bottom of the first damping element and the second damping element is provided with a force sensor; the top of the light oscillator and the light plate, and the first base and the second base are provided with an acceleration sensor; the force sensor is used for collecting the force response in the test vibration system; and the acceleration sensor is used for collecting the acceleration response in the test vibration system.

5. The vibration test platform of claim 1, wherein The lifting mechanism comprises a portal frame, a lifting hook and a loading device; the lifting hook is symmetrically arranged on the beam of the portal frame and is used for lifting the test mechanism at a long distance; the loading device is arranged on the beam of the portal frame and is used for applying a load to the test mechanism; the bottom of the portal frame is in sliding fit with the sliding groove and is fixedly connected with the bottom plate after sliding to a specified position.

6. The vibration test platform according to claim 5, wherein The loading device comprises one or more of a handheld force hammer, a drop hammer, a vibration exciter and an actuator.

7. The vibration test platform of claim 6, wherein The loading device is the handheld force hammer, the handheld force hammer vertically hammers the center of the top surface of the single-degree-of-freedom vibrator or the vibration plate, and an internal force sensor of the handheld force hammer measures the pulse excitation force input to the vibration system. Alternatively, the loading device is the drop hammer, the drop hammer freely impacts the center of the top surface of the single-degree-of-freedom vibrator or the vibration plate, the height of the drop hammer is controlled to control the size of the excitation force of each time to be maintained at a required force value. Alternatively, the loading device is the vibration exciter, the vibration exciter applies a load downward, the excitation point is at the center of the top surface of the single-degree-of-freedom vibrator or the vibration plate, a specific frequency or swept sine load or pulse excitation or white noise excitation is applied, and a force sensor is arranged at the head of the loading rod of the vibration exciter to measure the excitation force input to the vibration system. Alternatively, the loading device is the actuator, the actuator applies a load downward, the excitation point is at the center of the top surface of the single-degree-of-freedom vibrator or the vibration plate, a specific frequency or swept sine load or pulse excitation or white noise excitation or wheel-rail force load spectrum is applied to excite the wheel-rail force, and a force sensor is arranged at the head of the actuator to measure the excitation force input to the vibration system.

Images