Method and device for testing vibration attenuation rate of steel rail

Abstract

The invention discloses a steel rail vibration attenuation rate testing method, which comprises the following steps of: performing load application calibration on a steel rail to be tested to obtain a standard exciting force; setting an initial position on the steel rail to be tested, and arranging a second displacement sensor at the initial position; setting measuring points on the to-be-tested steel rail according to the sleeper spacing of the to-be-tested steel rail from the starting position; sequentially applying standard exciting force with fixed amplitude to the steel rail at all the measuring points by using a testing device running at a constant speed, recording a first vibration displacement signal at each measuring point, and recording a second vibration displacement signal correspondingly acquired at a starting position when the standard exciting force with fixed amplitude is applied to each measuring point; the first vibration displacement signals at all the measuring points and the second vibration displacement signals corresponding to the initial positions are processed to obtain a plurality of corresponding acceleration signals, and the rail vibration attenuation rate is calculated according to the acceleration signals and the sleeper distance of the to-be-tested rail, so that the rail vibration attenuation rate testing efficiency and accuracy can be improved.

Description

Technical Field

[0001] The invention relates to a method and a device for testing rail vibration attenuation rate, and belongs to the technical field of rail vibration testing. Background Art

[0002] Rail vibration decay rate DR (Decay Rate) is an important indicator for quantifying the dynamic damping characteristics and longitudinal vibration transmission capacity of the track system. This indicator describes the vibration attenuation capacity of the track system along the longitudinal direction of the rail in a 1 / 3 octave frequency band. If the rail vibration decay rate is too low in a certain frequency band, it indicates that the dynamic damping of the track system in this frequency band is low, the vibration transmission capacity along the longitudinal direction of the rail is strong, and the rail has a tendency to vibrate violently without being restrained by fasteners, which is easy to have many adverse effects on rail vehicles. Therefore, it is necessary to detect the rail status in a timely manner.

[0003] At present, the rail vibration attenuation rate test is carried out according to the specification BS EN15461: 2008+A1: 2010. However, according to the existing test specifications, the operation is difficult, the efficiency is low, and the accuracy needs to be improved: each tapping point needs to be tapped at least 5 times, and a test needs to constantly change the position and tap dozens of points, which is very labor-intensive and time-consuming; at the same time, the force of each person's tapping is different each time, and it is easy for the tapping force to be too large and the vibration response to exceed the range of the acceleration sensor, resulting in invalid test data; at the same time, before each tapping, it is necessary to measure and mark the position of the tapping point on the rail in advance, which is very time-consuming. Summary of the invention

[0004] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a method and device for testing rail vibration attenuation rate to improve testing efficiency and accuracy.

[0005] In order to achieve the above purpose / solve the above technical problems, the present invention is implemented by adopting the following technical solutions: In a first aspect, the present invention provides a method for testing rail vibration attenuation rate, the method comprising: Calibrate the load on the rail to be tested to obtain the standard exciting force; Setting a starting position on the rail to be tested, and arranging a second displacement sensor at the starting position; From the starting position, set measuring points on the rail to be tested according to the sleeper spacing of the rail to be tested; A test device running at a constant speed is used to sequentially apply a standard exciting force of a fixed amplitude to the rails at all measuring points, and a first vibration displacement signal at each measuring point is recorded, and a second vibration displacement signal corresponding to the starting position when the standard exciting force of a fixed amplitude is applied at the measuring point is recorded; The first vibration displacement signals at all measuring points and the second vibration displacement signals corresponding to the starting position are processed to obtain a plurality of corresponding acceleration signals, and the rail vibration attenuation rate is calculated according to the plurality of corresponding acceleration signals and the sleeper spacing of the rail to be tested.

[0006] Optionally, the step of applying a load to the rail to be tested to obtain a standard exciting force includes: Use a force hammer to perform a static hammer strike at any location of the rail to be tested, and collect the excitation load F1 of the force hammer and the vibration displacement signal X1 at this location; Use a vibration exciter to excite the same location of the rail to be tested, and collect the vibration displacement signal X2 at this location; Based on the vibration displacement signal X1 and the vibration displacement signal X2, a calibration coefficient k is calculated, and a standard exciting force F2=k*F1 is calculated according to the calibration coefficient k.

[0007] Optionally, the calibration coefficient k is calculated based on the vibration displacement signal X1 and the vibration displacement signal X2, including: Performing Fourier transform on the vibration displacement signal X1 and the vibration displacement signal X2 respectively to obtain a 1 / 3 octave value of the vibration displacement signal X1 and a 1 / 3 octave value of the vibration displacement signal X2; The 1 / 3 octave value of the vibration displacement signal X2 is compared with the 1 / 3 octave value of the vibration displacement signal X1 to obtain the calibration coefficient k at the 1 / 3 octave.

[0008] Optionally, the first vibration displacement signals at all measuring points and the second vibration displacement signals corresponding to the starting position are processed to obtain a plurality of corresponding acceleration signals, including: Obtain the distance between two adjacent measuring points in turn according to the sleeper distance and the setting measuring point position ; in, is the distance between the nth measuring point and the n-1th measuring point; Get the time interval between the test device passing through two adjacent test points in sequence , which is expressed as follows: ; in, is the speed of the test device moving at a constant speed, is the time interval between the nth measuring point and the n-1th measuring point; According to the corresponding time interval The first vibration displacement signals at all measuring points and the second vibration displacement signals corresponding to the starting position are derivatized twice to obtain a plurality of corresponding acceleration signals, namely, the acceleration signals at all measuring points and the acceleration signal corresponding to the starting position when a standard exciting force with a fixed amplitude is applied.

[0009] Optionally, calculating the rail vibration attenuation rate according to the plurality of corresponding acceleration signals and the sleeper spacing of the rail to be tested includes: The rail vibration attenuation rate DR is calculated according to the following formula: ; Among them, n is the nth measurement point, is the acceleration signal at the nth measuring point, The acceleration signal corresponding to the starting position when a standard excitation force with a fixed amplitude is applied to the nth measuring point. is the distance from the nth measuring point to the starting position.

[0010] Optionally, the method further includes: When there is a track form in the rail section to be tested, load application calibration is performed multiple times on the track form to obtain multiple standard exciting forces; Calculating an average value of the plurality of standard exciting forces; The average value is taken as the final standard exciting force of the track form.

[0011] Optionally, the method further includes: When multiple test devices are used for testing, the rail vibration attenuation rate when each test device passes through the same measuring point is calculated separately; Calculating an average value of the rail vibration attenuation rates corresponding to the multiple test devices; The average value is taken as the final rail vibration attenuation rate corresponding to the measuring point.

[0012] Optionally, the method further includes: When the steel rail to be tested has multiple track forms, one or more measuring points are set on the steel rail of each track form; The rail vibration attenuation rate of each track type is calculated through the set measuring points.

[0013] In a second aspect, the present invention provides a rail vibration attenuation rate testing device, including a load applying exciter, a first displacement sensor and a signal acquisition device; The load applying exciter is used to apply load excitation; The first displacement sensor is used to collect the vibration displacement signal of the applied load excitation; The signal acquisition device is used to collect the applied load excitation magnitude and vibration displacement signal, and transmit them to the data processing terminal and the data storage device.

[0014] Compared with the prior art, the present invention has the following beneficial effects: Before conducting the rail vibration attenuation rate test, the load on the test rail is calibrated to obtain the standard exciting force. This method is suitable for rails with different characteristics. The standard exciting force obtained during calibration is used in subsequent tests to improve the accuracy and reliability of the test results. By applying the standard exciting force at the measuring point, the vibration displacement signal at the measuring point and the vibration displacement signal at the corresponding starting position are collected, and the rail vibration attenuation rate is calculated. Compared with the method of manually performing a force hammer test and the method of using a running train for testing, this method is simpler, has higher test efficiency, does not require the deployment of acceleration sensors on the track, and has lower test costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic flow chart of a rail vibration attenuation rate testing method provided by an embodiment of the present invention; Figure 2 It is a schematic diagram of a module of a rail vibration attenuation rate testing device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0016] The technical solution of the present invention is described in detail below through the accompanying drawings and specific embodiments. It should be understood that the embodiments of the present application and the specific features in the embodiments are detailed descriptions of the technical solution of the present application, rather than limitations on the technical solution of the present application. In the absence of conflict, the embodiments of the present application and the technical features in the embodiments can be combined with each other.

[0017] In the description of the present invention, if “first” or “second” is described, it is only used for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0018] In the description of the present invention, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0019] Example 1

[0020] like Figure 1 As shown, the present invention provides a method for testing rail vibration attenuation rate, and the specific steps are as follows: S01: Calibrate the load on the test rail to obtain the standard exciting force; S02: setting a starting position on the rail to be tested, and placing a second displacement sensor at the starting position; S03: Starting from the starting position, setting measuring points on the rail to be tested according to the sleeper spacing of the rail to be tested; S04: using a testing device traveling at a constant speed to sequentially apply a standard exciting force of a fixed amplitude to the rails at all measuring points, and simultaneously recording a first vibration displacement signal at each measuring point, and simultaneously recording a second vibration displacement signal collected corresponding to the starting position when the standard exciting force of a fixed amplitude is applied at the measuring point each time; S05: Processing the first vibration displacement signals at all measuring points and the second vibration displacement signals corresponding to the starting position to obtain a plurality of corresponding acceleration signals, and calculating the rail vibration attenuation rate according to the plurality of corresponding acceleration signals and the sleeper spacing of the rail to be tested.

[0021] The present invention provides a rail vibration attenuation rate testing method. Before the rail vibration attenuation rate test is performed, a load is applied and calibrated on the rail to be tested to obtain a standard exciting force, thereby improving the accuracy and reliability of the test result. By applying the standard exciting force at a measuring point, a vibration displacement signal at the measuring point and a vibration displacement signal at a corresponding starting position are correspondingly collected, and the rail vibration attenuation rate is calculated. Compared with a method of manually performing a force hammer test and a method of performing a test using a running train, the method is simpler, has a higher test efficiency, does not require the deployment of an acceleration sensor on a track, and has a lower test cost.

[0022] In this embodiment, in step S01, load application calibration is performed on the test rail to obtain a standard exciting force, and the specific steps are as follows: Use a force hammer to perform a static hammer strike at any location of the rail to be tested, and collect the excitation load F1 of the force hammer and the vibration displacement signal X1 at this location; Use a vibration exciter to excite the same location of the rail to be tested, and collect the vibration displacement signal X2 at this location; Based on the vibration displacement signal X1 and the vibration displacement signal X2, a calibration coefficient k is calculated, and a standard exciting force F2=k*F1 is calculated according to the calibration coefficient k.

[0023] Specifically, due to the different inherent stiffness and damping of different rail lines, even if the same excitation force is applied, the relationship between the excitation force and the response will still be different. Therefore, load application calibration is performed before each measurement, and the rail vibration displacement signal is collected and converted into a force signal in proportion to improve the test accuracy.

[0024] Specifically, the step of calculating the calibration coefficient k based on the vibration displacement signal X1 and the vibration displacement signal X2 includes: Performing Fourier transform on the vibration displacement signal X1 and the vibration displacement signal X2 respectively to obtain a 1 / 3 octave value of the vibration displacement signal X1 and a 1 / 3 octave value of the vibration displacement signal X2; The 1 / 3 octave value d2 of the vibration displacement signal X2 is compared with the 1 / 3 octave value d1 of the vibration displacement signal X1 to obtain the calibration coefficient k=d2 / d1 at the 1 / 3 octave.

[0025] Specifically, the rail vibration attenuation rate test is performed using the calibration coefficient k in the 1 / 3 octave band.

[0026] In this embodiment, in step S02, a starting position is set on the rail to be tested, and a second displacement sensor is arranged at the starting position; wherein the second displacement sensor collects data and transmits it to a collection terminal or a data processing terminal for subsequent data processing. Specifically, the second displacement sensor is an eddy current displacement sensor.

[0027] In this embodiment, in step S03, starting from the starting position, measuring points are set on the rail to be tested according to the sleeper spacing of the rail to be tested; Specifically, the sleeper spacing of different rail lines is different, and the sleeper spacing of the rail to be tested can be obtained by manual measurement; the measuring points are arranged according to the specification BS EN15461: 2008+A1: 2010, specifically 68 locations, including the sleeper location, the center of the sleeper spacing, 1 / 4 and 3 / 4 of the sleeper spacing, and no further details will be given here. The measuring points can be arranged according to the sleeper spacing of the rail to be tested.

[0028] In this embodiment, in step S04, a test device traveling at a constant speed is used to sequentially apply a standard exciting force of a fixed amplitude to the rails at all measuring points, and simultaneously record a first vibration displacement signal at each measuring point, and simultaneously record a second vibration displacement signal corresponding to the starting position when the standard exciting force of a fixed amplitude is applied at each measuring point; Specifically, the test device can be a test cart commonly used in the art, or it can be the test device disclosed in Example 2 of the present application. It only needs to be provided with a force applying device and a signal acquiring device, and no excessive restrictions are made here.

[0029] Specifically, the first vibration displacement signal and the second vibration displacement signal are both transmitted to a collection terminal or a data processing terminal for subsequent data processing.

[0030] In this embodiment, in step S05, the first vibration displacement signals at all measuring points and the second vibration displacement signals corresponding to the starting position are processed to obtain a plurality of corresponding acceleration signals, and the rail vibration attenuation rate is calculated according to the plurality of corresponding acceleration signals and the sleeper spacing of the rail to be tested, specifically including: (I) Obtaining multiple corresponding acceleration signals: Obtain the distance between two adjacent measuring points in turn according to the sleeper distance and the setting measuring point position ; in, is the distance between the nth measuring point and the n-1th measuring point; Get the time interval between the test device passing through two adjacent test points in sequence : ; in, is the speed of the test device moving at a constant speed, is the time interval between the nth measuring point and the n-1th measuring point; According to the corresponding time interval The first vibration displacement signals at all measuring points and the second vibration displacement signals corresponding to the starting position are derivatized twice to obtain a plurality of corresponding acceleration signals, namely, the acceleration signals at all measuring points and the acceleration signal corresponding to the starting position when a standard exciting force with a fixed amplitude is applied.

[0031] Calculate the rail vibration attenuation rate: The rail vibration attenuation rate DR is calculated according to the following formula: ; Among them, n is the nth measurement point, is the acceleration signal at the nth measuring point, The acceleration signal corresponding to the starting position when a standard excitation force with a fixed amplitude is applied to the nth measuring point. is the distance from the nth measuring point to the starting position.

[0032] According to an embodiment of the present invention, when there is a track form in the rail section to be tested, load application calibration is performed on the track form multiple times to obtain multiple standard exciting forces; the average value of the multiple standard exciting forces is calculated; and the average value is used as the final standard exciting force of the track form. The specific test and calculation method of the rail vibration attenuation rate is as described above and will not be repeated here.

[0033] According to an embodiment of the present invention, when multiple test devices are used for testing, at the same measuring point, the rail vibration attenuation rate when each test device passes through is calculated respectively; the average value of the rail vibration attenuation rates corresponding to the multiple test devices is calculated; and the average value is used as the final rail vibration attenuation rate corresponding to the measuring point. The specific test and calculation method of the rail vibration attenuation rate is as described above and will not be repeated here.

[0034] According to an embodiment of the present invention, when there are multiple track forms in the rail to be tested, one or more measuring points are set on the rail of each track form; the rail vibration attenuation rate of each track form is calculated respectively through the set measuring points. The specific test and calculation method of the rail vibration attenuation rate is as described above and will not be repeated here.

[0035] Example 2

[0036] like Figure 2 As shown, the present invention provides a rail vibration attenuation rate testing device, including a load applying exciter, a first displacement sensor and a signal acquisition device; The load applying exciter is used to apply load excitation; The first displacement sensor is used to collect the vibration displacement signal of the applied load excitation; The signal acquisition device is used to collect the applied load excitation magnitude and vibration displacement signal, and transmit them to the data processing terminal and the data storage device.

[0037] In some embodiments, the testing device also includes a driving device, which includes a driving motor and a controller for driving the testing device to move forward. The controller is electrically connected to the load application exciter and the driving motor, respectively, and is used to control the size of the load applied and to simply control the travel speed and distance of the testing device.

[0038] The rail vibration attenuation rate testing device provided in the embodiment of the present invention can execute the rail vibration attenuation rate testing method provided in any embodiment of the present invention, and has the corresponding functional modules and beneficial effects of the execution method.

[0039] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A rail vibration attenuation rate testing method, characterized in that: The method comprises: Calibrate the load on the rail to be tested to obtain the standard exciting force; Setting a starting position on the rail to be tested, and arranging a second displacement sensor at the starting position; From the starting position, set measuring points on the rail to be tested according to the sleeper spacing of the rail to be tested; A test device running at a constant speed is used to sequentially apply a standard exciting force of a fixed amplitude to the rails at all measuring points, and a first vibration displacement signal at each measuring point is recorded, and a second vibration displacement signal corresponding to the starting position when the standard exciting force of a fixed amplitude is applied at the measuring point is recorded; The first vibration displacement signals at all measuring points and the second vibration displacement signals corresponding to the starting position are processed to obtain a plurality of corresponding acceleration signals, and the rail vibration attenuation rate is calculated according to the plurality of corresponding acceleration signals and the sleeper spacing of the rail to be tested.

2. The rail vibration attenuation rate testing method according to claim 1, characterized in that: The load application and calibration of the rail to be tested to obtain a standard exciting force comprises: Use a force hammer to perform a static hammer strike at any location of the rail to be tested, and collect the excitation load F1 of the force hammer and the vibration displacement signal X1 at this location; Use a vibration exciter to excite the same location of the rail to be tested, and collect the vibration displacement signal X2 at this location; Based on the vibration displacement signal X1 and the vibration displacement signal X2, a calibration coefficient k is calculated, and a standard exciting force F2=k*F1 is calculated according to the calibration coefficient k.

3. The rail vibration attenuation rate testing method according to claim 2, characterized in that: The calibration coefficient k is calculated based on the vibration displacement signal X1 and the vibration displacement signal X2, including: Performing Fourier transform on the vibration displacement signal X1 and the vibration displacement signal X2 respectively to obtain a 1 / 3 octave value of the vibration displacement signal X1 and a 1 / 3 octave value of the vibration displacement signal X2; The 1 / 3 octave value of the vibration displacement signal X2 is compared with the 1 / 3 octave value of the vibration displacement signal X1 to obtain the calibration coefficient k at the 1 / 3 octave.

4. The rail vibration attenuation rate testing method according to claim 1, characterized in that: The first vibration displacement signals at all measuring points and the second vibration displacement signals corresponding to the starting position are processed to obtain a plurality of corresponding acceleration signals, including: Obtain the distance between two adjacent measuring points in turn according to the sleeper distance and the setting measuring point position ; in, is the distance between the nth measuring point and the n-1th measuring point; Get the time interval between the test device passing through two adjacent test points in sequence , which is expressed as follows: ； in, is the speed of the test device moving at a constant speed, is the time interval between the nth measuring point and the n-1th measuring point; According to the corresponding time interval The first vibration displacement signals at all measuring points and the second vibration displacement signals corresponding to the starting position are derivatized twice to obtain a plurality of corresponding acceleration signals, namely, the acceleration signals at all measuring points and the acceleration signal corresponding to the starting position when a standard exciting force with a fixed amplitude is applied.

5. The rail vibration attenuation rate testing method according to claim 4, characterized in that: The method further comprises: calculating the rail vibration attenuation rate according to the plurality of corresponding acceleration signals and the sleeper spacing of the rail to be tested, comprising: The rail vibration attenuation rate DR is calculated according to the following formula: ； Among them, n is the nth measurement point, is the acceleration signal at the nth measuring point, The acceleration signal corresponding to the starting position when a standard excitation force with a fixed amplitude is applied to the nth measuring point. is the distance from the nth measuring point to the starting position.

6. The rail vibration attenuation rate testing method according to claim 1, characterized in that: The method further comprises: When there is a track form in the rail section to be tested, load application calibration is performed multiple times on the track form to obtain multiple standard exciting forces; Calculating an average value of the plurality of standard exciting forces; The average value is taken as the final standard exciting force of the track form.

7. The rail vibration attenuation rate testing method according to claim 1, characterized in that: The method further comprises: When multiple test devices are used for testing, the rail vibration attenuation rate when each test device passes through the same measuring point is calculated separately; Calculating an average value of the rail vibration attenuation rates corresponding to the multiple test devices; The average value is taken as the final rail vibration attenuation rate corresponding to the measuring point.

8. The rail vibration attenuation rate testing method according to claim 1, characterized in that: The method further comprises: When the steel rail to be tested has multiple track forms, one or more measuring points are set on the steel rail of each track form; The rail vibration attenuation rate of each track type is calculated through the set measuring points.

9. A rail vibration attenuation rate testing device, characterized in that: It includes a load applying vibrator, a first displacement sensor and a signal acquisition device; The load applying exciter is used to apply load excitation; The first displacement sensor is used to collect the vibration displacement signal of the applied load excitation; The signal acquisition device is used to collect the applied load excitation magnitude and vibration displacement signal, and transmit them to the data processing terminal and the data storage device.

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