Railway sound barrier fatigue testing machine

Abstract

The utility model discloses a railway sound barrier fatigue testing machine. The fatigue testing machine comprises an actuator; each bearing device comprises a load sensor for collecting fatigue load, a steel stand column connected with the sensor, and a bearing frame connected with the sensor and the steel stand column; the load transmission device comprises a steel tank and an air bag which can be mutually contacted or fixedly connected, and horizontal bubbles are arranged on the upper surface of the side wall of the steel tank; and the actuator is connected with the steel tank. The railway sound barrier fatigue testing machine can accurately measure the fatigue load or the corresponding wind pressure borne by a sound barrier sample, and the fatigue load or the corresponding wind pressure can be used as a feedback signal to guide the testing machine to load the load, so that the problem of inaccurate measurement of the load borne by the tested sample caused by tool inertia is avoided. The testing machine can also uniformly distribute loads on the stress surface of the sound barrier, and can be suitable for the concave-convex design condition of the sound barrier panel, so that the application range of the testing machine is expanded.

Description

Technical Field

[0001] This utility model relates to a device for evaluating the mechanical properties of sound barrier components; more specifically, it relates to a fatigue testing machine for railway sound barriers. Background Technology

[0002] Currently, fatigue testing of railway sound barriers involves placing the sound barrier between two fixed steel sections and applying compressive fatigue loads to the panels on both sides of the sound barrier, causing the sound barrier panels to undergo indentation deformation.

[0003] Common fatigue testing machines typically have a load sensor at the end of the actuator to measure the load output by the actuator. This load serves as feedback to adjust the machine's applied load. When the actuator is in direct contact with the test sample, the load output by the actuator is essentially the same as the load on the test sample. When the fatigue load is unidirectional (e.g., compressive fatigue or tensile fatigue), the load output by the actuator is also essentially the same as the load on the test sample. However, when a heavy fixture is used to connect the actuator and the test sample, the fatigue load is unidirectional (tensile-compressive fatigue), or the loading frequency is high, the load measured by the load sensor at the actuator end reflects the actual load on the test sample and the inertial force of the fixture, rather than the actual load on the test sample, due to the inertia of the heavy fixture.

[0004] Existing sound barrier fatigue testing machines, such as Figure 9 and Figure 10 As shown, it uses a traditional electro-hydraulic servo fatigue testing machine with an added loading frame for fatigue testing. The load sensor 8 connected to actuator 1 is used as a feedback signal to adjust the fatigue loading load. The sound barrier slot 15 simulates two H-beams for fixing the sound barrier. The loading frame consists of a pressure plate 12, a force plate 13, and fixing screws. The force plate 13 (generally made of steel) directly contacts the sound barrier, and there is a gap between the force plates 13. The loading method involves actuator 2 pushing the pressure plate 12, causing the force plate 13 to directly contact the sound barrier and bear the load. The load sensor 8 connected to actuator 2 is used as a feedback signal to adjust the fatigue loading load.

[0005] During the loading process, the existing testing machine causes the sound barrier panel to indent under load, with only the two edges of the load plate in contact with the sound barrier. This results in the main contact load being concentrated at the two edges, making it impossible to simulate the uniform loading process of wind pressure. In addition, the load received by the load sensor is the sum of the inertial force of the loading frame and the load acting on the sound barrier, which cannot accurately measure the actual fatigue load on the sound barrier. Utility Model Content

[0006] To overcome the problems of poor accuracy and systematic errors in existing sound barrier fatigue testing machines, this invention provides a railway sound barrier fatigue testing machine. This fatigue testing machine can simulate the uniform loading process of wind pressure, thereby accurately measuring the actual fatigue load on the sound barrier.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] A fatigue testing machine for railway sound barriers includes the following structure:

[0009] Actuator;

[0010] Multiple load-bearing devices are included, each of which includes a load sensor for collecting fatigue loads, a steel column connected to the sensor, and a load-bearing frame connected to both the sensor and the steel column; during the experiment, the sound barrier sample is placed on the load-bearing frame.

[0011] The load transfer device includes a steel trough and an air bladder that can contact or be fixed together, and the upper surface of the side wall of the steel trough is provided with horizontal air bubbles.

[0012] The actuator is connected to the steel trough.

[0013] Furthermore, a barometer is installed inside the airbag.

[0014] Furthermore, the steel column is H-shaped.

[0015] Furthermore, the actuator is connected to an actuator reaction frame that balances fatigue loads.

[0016] Furthermore, the railway sound barrier fatigue testing machine is also equipped with an assembly screw that connects the steel groove and the airbag as a whole.

[0017] Furthermore, the assembly screw is equipped with an assembly nut with adjustable steel groove spacing.

[0018] Furthermore, the number of "multiple" refers to four. For balance considerations, the number of supporting devices is generally three or more, preferably four.

[0019] Furthermore, the support frame is provided with a support frame sidewall that serves as a barrier.

[0020] The load sensor is mounted on the rear of the bearing frame of this testing machine. Since the bearing frame is in direct contact with the sound barrier sample, the bearing frame, load sensor and steel column are tightly connected. The load sensor can accurately measure the actual fatigue load on the sound barrier during the fatigue process, without being affected by the inertial force of the tooling.

[0021] This testing machine uses an airbag containing a barometer to accurately measure changes in air pressure within the airbag. Since the air inside the airbag flows freely, the internal pressure can be considered constant. As the airbag is compressed and its volume decreases, the internal air pressure gradually increases. This internal pressure is equal to the pressure at the contact surface with the airbag. The load sensor can accurately measure the actual pressure (i.e., fatigue load) experienced by the sound barrier during fatigue, unaffected by the inertial forces of the tooling.

[0022] The average load detected by the two sensors on the stressed side can be used as a feedback signal for the fatigue testing machine's loading, avoiding the problem of inaccurate load measurement on the tested sample caused by tooling inertia. Similarly, the barometer inside the airbag can also be used as a feedback signal for the fatigue testing machine's loading, avoiding the problem of inaccurate load measurement on the tested sample caused by tooling inertia.

[0023] The basic functions of each component of this utility model are as follows:

[0024] (1) Actuator reaction frame: connected to the actuator, used to balance the fatigue load applied by the actuator to the sound barrier.

[0025] (2) Actuator: used to apply fatigue test load to simulate train pulsating wind pressure.

[0026] (3) Steel channel: Transmits load and connects the actuator and the airbag. The steel channel has side walls around its perimeter, and the airbag is installed inside the side walls. The upper surface of the side walls has a level bubble for adjusting the levelness of the steel channel. The back of the steel channel has assembly holes for assembly with bolts and nuts. The back also has a pre-drilled hole for the barometer wires to pass through.

[0027] (4) Airbag: Transmits load, connected to the steel channel on one side and in contact with the sound barrier on the other side to transmit fatigue load. The contact surface between the airbag and the steel channel is fitted with Velcro for easy fixation. An internal pressure gauge is installed in the airbag to test the internal pressure.

[0028] Analysis of the airbag loading process:

[0029] ① When the actuator is pushed out, the airbag in the relaxed state in one side of the steel groove comes into contact with the sound barrier. The contact area between the two parts gradually increases until the exposed part of the force-bearing surface of the sound barrier is in complete contact with the airbag. Since the airbag is in a relaxed state, the air pressure inside the airbag is still the same as the outside air pressure. At this time, the sound barrier can be regarded as not being subjected to compressive load, only the contact load between the airbag and the sound barrier (which can be ignored).

[0030] ② As the actuator continues to extend, the airbag volume decreases and the internal pressure of the airbag gradually increases. Since the airbag is in complete contact with the force-bearing surface of the sound barrier, the force-bearing surface of the sound barrier in contact with the airbag begins to be subjected to a uniform compressive load.

[0031] ③ As the actuator continues to extend, the airbag volume decreases further, increasing the internal pressure. The sound barrier panel in contact with the airbag begins to show a larger indentation in the center and a smaller indentation around the edges. Due to airflow, the air pressure is uniform throughout the airbag, causing the airbag to deform in the same way as the sound barrier. This results in a larger bulge in the center of the airbag at the contact surface with the sound barrier, and a smaller bulge around the edges. At this point, the stress surface of the sound barrier in contact with the airbag is still under a uniformly distributed load. This continues until the sound barrier reaches the fatigue program load requirement. The pressure displayed by the barometer inside the airbag is the corresponding wind pressure on the sound barrier. Based on feedback from the load sensor or barometer, the actuator stops extending at this point.

[0032] ④ As the actuator contracts, the airbag volume increases, the internal pressure of the airbag decreases, and the sound barrier panel in contact with the airbag gradually returns to a flat state. During this process, because the airbag and the sound barrier deform in the same way, the stress-bearing surface of the sound barrier in contact with the airbag is still subjected to a uniformly distributed load.

[0033] ⑤ As the actuator continues to contract, the airbag disengages from the sound barrier panel. At this time, the airbag on the other side repeats steps ①-④ with the other side panel of the sound barrier, completing one fatigue loading cycle.

[0034] (5) Assemble the screw: Assemble the two steel channels and the two airbags into a whole.

[0035] (6) Assemble the nuts: Adjust the distance between the two steel grooves so that the airbags on both sides are in contact with the surface of the sound barrier before the fatigue test, and no pressure is generated.

[0036] (7) H-beam steel column: connected to the load sensor to balance the fatigue load on the sound barrier sample. The bottom of the H-beam steel column has positioning holes for adjusting the spacing of the bearing frame to the specified distance for the test.

[0037] (8) Load sensor: collects fatigue loads acting on the sound barrier.

[0038] (9) Support frame: Connected to the H-beam steel column and load sensor. The sound barrier sample is placed on this support frame. The side walls of the support frame are used to prevent excessive lateral sliding of the sound barrier sample during fatigue, thus acting as a barrier. Bolts are used to tightly connect the support frame, load sensor, and H-beam steel column through the connecting step holes.

[0039] (10) Sound barrier sample: a plate acoustic component module with sound absorption and insulation properties, which is subjected to fatigue load in fatigue test.

[0040] Compared with the prior art, the beneficial effects of this utility model are:

[0041] 1. It can accurately measure the fatigue load or corresponding wind pressure on the sound barrier sample, and use this as a feedback signal to guide the testing machine to apply load, avoiding the problem of inaccurate load measurement of the tested sample caused by tooling inertia.

[0042] 2. It can evenly distribute the load on the stress surface of the sound barrier. It is suitable for sound barrier panels with uneven designs, thus expanding the application range of this testing machine. Attached Figure Description

[0043] Figure 1 This is a structural schematic diagram of the fatigue testing machine for railway sound barriers according to this utility model.

[0044] Figure 2 This is a side view schematic diagram of the fatigue testing machine for railway sound barriers according to this utility model.

[0045] Figure 3 This is a schematic diagram of the main view of the steel channel.

[0046] Figure 4 This is a side view schematic diagram of the steel trough with attached airbag.

[0047] Figure 5 This is a partial schematic diagram of the assembly of two steel channels with attached airbags.

[0048] Figure 6 This is a top view of the assembly of the H-shaped steel column, load sensor, and load-bearing frame.

[0049] Figure 7 This is a front view schematic diagram of the combined H-shaped steel column, load sensor, and load-bearing frame.

[0050] Figure 8 This is a top-down view of the assembled H-beam steel column, load sensor, support frame, and sound barrier sample.

[0051] Figure 9 This is a schematic diagram of an existing sound barrier fatigue testing machine.

[0052] Figure 10 yes Figure 9 Sectional view along line A-A.

[0053] Explanation of reference numerals in the attached figures:

[0054] 1—Actuator reaction frame; 2—Actuator; 3—Steel channel; 32—Horizontal bubble; 4—Airbag; 41—Barometer; 5—Assembly screw; 6—Assembly nut; 7—H-shaped steel column; 8—Load sensor; 9—Bearing frame; 10—Sound barrier sample; 31—Steel channel sidewall; 32—Horizontal bubble; 33—Assembly hole; 34—Barometer wire pre-drilled hole; 91—Bearing frame sidewall; 92—Bearing platform; 93—Connecting step hole; 12—Pressure plate; 13—Force plate; 14—Fixing bolt; 15—Sound barrier slot. Detailed Implementation

[0055] Example 1

[0056] like Figures 1 to 8 As shown, the fatigue testing machine for railway sound barriers of this utility model includes the following structure:

[0057] Actuator 2;

[0058] Four load-bearing devices are included, each comprising a load sensor 8 for collecting fatigue loads, an H-shaped steel column 7 connected to the sensor 8, and a support frame 9 connected to both the sensor 8 and the H-shaped steel column 7; the aforementioned actuator 2 is connected to a steel channel 3. During the experiment, the sound barrier sample 10 is placed on the support frame 9.

[0059] The load transfer device includes a steel trough 3 and an airbag 4 that can contact or be fixed together. A horizontal air bubble 32 is provided on the upper surface of the side wall 31 of the steel trough. The steel trough 3 also has an assembly hole 33 and a reserved hole 34 for the barometer wire. Figure 1 and Figure 3 As shown. A pressure gauge 41 is installed inside the airbag 4, as... Figure 4 As shown.

[0060] like Figure 1 As shown, the aforementioned actuator 2 is connected to an actuator reaction frame 1 that balances fatigue loads.

[0061] like Figure 8 As shown, there are a total of 4 load-bearing devices, including the support frame 9, load sensor 8, and H-shaped steel column 7. The spacing between the 4 assemblies is adjusted so that the horizontal and vertical spacing of the 4 support frames 9 is consistent with the spacing required for the sound barrier sample. The H-shaped steel column is fixed and the sound barrier sample 10 is placed on the support frame 9.

[0062] like Figure 1 As shown, the railway sound barrier fatigue testing machine is also equipped with an assembly screw 5 that connects the aforementioned steel groove 3 and airbag 4 into one unit. The assembly screw 5 is equipped with an assembly nut 6 that can adjust the distance between the two steel grooves 3.

[0063] like Figure 6 and Figure 7 As shown, the aforementioned support frame is provided with a support frame sidewall 91 that serves as a barrier. Each support device is provided with a support platform 92 for placing the sound barrier sample 10 and a connecting step hole 93 for installation.

[0064] The specific steps for using the railway sound barrier fatigue testing machine described in Example 1 are as follows:

[0065] 1. Use bolts to tightly connect the sound barrier support frame 9, load sensor 8, and H-beam steel column 7 through the connecting step hole 93. Adjust the spacing of the four H-beam steel columns so that the horizontal and vertical spacing of the four sound barrier support frames is consistent with the required spacing of the sound barrier sample. Place the sound barrier sample 10 on the support frame 9.

[0066] 2. Inflate air into airbag 4 and observe the barometer 41 and the state of airbag 4, ensuring that airbag 4 is not fully inflated and is not pressurized internally (with the same air pressure as the outside air), and that the contact surface with the sound barrier sample 10 is relaxed. Insert airbag 4 into the two steel grooves 3 respectively, and secure the airbag 4 to the steel grooves 3 using Velcro. Place the two steel grooves 3 with the airbag 4 fixed on them on both sides of the sound barrier sample 10, tighten the bolts through the assembly holes, and use the assembly nuts 6 to adjust the distance between the two airbags 4 so that before the fatigue test, the airbags 4 on both sides are in contact with the surface of the sound barrier sample 10 without generating pressure. Adjust the orientation of the two steel grooves 3 so that the horizontal bubble 32 on the steel groove 3 is centered, and tighten the fixing assembly nuts 6 to assemble the two steel grooves 3 with the airbag 4 fixed into a single unit.

[0067] 3. The steel channel 3 on one side is connected to the actuator 2, and the actuator 2 is connected to the actuator reaction frame 1. At this time, the fatigue program of the testing machine is started, the test parameters are set according to the standard, and the test is started.

[0068] The fatigue testing machine for railway sound barriers involved in this utility model has been described in detail above. Specific examples have been used to illustrate the principle and implementation of this utility model. The descriptions of the above embodiments are only for the purpose of helping to understand the solution and core idea of ​​this utility model. It should be noted that this utility model is not limited to the exemplary embodiments described above. Those skilled in the art can make various changes and modifications without departing from the scope or spirit of this utility model. Furthermore, for those skilled in the art, based on the idea of ​​this utility model, there will be changes in the specific implementation methods and application scope; therefore, the content of this specification should not be construed as a limitation of this utility model.

Claims

1. A fatigue testing machine for railway sound barriers, characterized in that, Includes the following structure: Actuator; Multiple load-bearing devices, each load-bearing device including a load sensor for collecting fatigue loads, a steel column connected to the sensor, and a load-bearing frame connected to both the sensor and the steel column; The load transfer device includes a steel trough and an air bladder that can contact or be fixed together, and the upper surface of the side wall of the steel trough is provided with horizontal air bubbles.

2. The fatigue testing machine for railway sound barriers according to claim 1, characterized in that, The airbag is equipped with a barometer.

3. The fatigue testing machine for railway sound barriers according to claim 1, characterized in that, The steel column is H-shaped.

4. The fatigue testing machine for railway sound barriers according to claim 1, characterized in that, The actuator is connected to an actuator reaction frame that balances fatigue loads.

5. The fatigue testing machine for railway sound barriers according to claim 1, characterized in that, It also includes an assembly screw that connects the steel channel and the airbag as a whole.

6. The railway sound barrier fatigue testing machine according to claim 5, characterized in that, The assembly screw is equipped with an assembly nut with adjustable steel groove spacing.

7. The fatigue testing machine for railway sound barriers according to claim 1, characterized in that, The number mentioned is four.

8. The fatigue testing machine for railway sound barriers according to claim 1, characterized in that, The support frame is provided with a support frame side wall that serves as a barrier.

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