Track vibration reduction effect monitoring method and system

Abstract

The present invention provides a method and system for monitoring the vibration reduction effect of a track. The method uses a load detection pad device under the rail in the track to detect the load under the rail when a train passes by and obtain a corresponding force signal. At the same time, the method uses a similar load detection pad device installed under the track bed plate to detect the force response signal under the track bed plate when a train passes by. Based on the collected force signal and force response signal, a corresponding admittance spectrum is calculated. The vibration reduction effect of the track is determined based on the comparison result of the admittance spectrum and a preset reference admittance spectrum. Since the load detection pad device integrated under the track directly detects the load of the train during actual operation, the method of the present invention can effectively detect the vibration reduction effect of the actual track. Since the load detection pad device is integrated under the track and does not affect the passage of the train, the method of the present invention can be used for long-term monitoring of the vibration reduction effect of the track without stopping the line for detection.

Description

Technical Field

[0001] The present invention belongs to the technical field of track vibration reduction and noise reduction, and in particular relates to a method and system for monitoring track vibration reduction effects. Background Art

[0002] With technological advancements, vibration-reducing track is increasingly being used. Research has shown that the actual vibration reduction effect of track is not only related to the performance of the track itself, but also to numerous factors, including line conditions, site environment, train axle load, and travel speed. Therefore, it is necessary to monitor the actual vibration reduction effect of vibration-reducing track in real-world application scenarios to ensure its effectiveness and provide a reference for future design and implementation of vibration-reducing track.

[0003] Currently, there's no unified method for monitoring track vibration reduction. A traditional approach involves installing an acceleration sensor at a designated location outside the track. The sensor detects the acceleration response signal at that location as a train passes by, and based on this signal, calculates the insertion loss between the vibration-reducing track and the undamped track. Insertion loss refers to the loss of load power caused by the insertion of a component or device at a certain point in the transmission system. Therefore, it can be used to assess the vibration reduction effectiveness of the vibration-reducing track relative to the undamped track. However, using this method, the measurement results contain both excitation and structural characteristics, which cannot be effectively distinguished. This leads to significant uncertainty in the measurement results, making it difficult to effectively determine the actual vibration reduction effectiveness of the track in real-world applications. Summary of the Invention

[0004] The present invention is made to solve the above-mentioned problems, and aims to provide a method and system for more accurately monitoring the vibration reduction effect of the track on-site. The present invention adopts the following technical solutions:

[0005] The present invention provides a method for monitoring track vibration reduction effects, characterized in that it comprises the following steps: step S1, when a train passes by, detecting the load under the rails of the track by means of a load detection pad device installed under the rails of two tracks, and acquiring corresponding force signals, wherein the load detection pad device includes at least one pressure sensor; step S2, when the train passes by, detecting the force response under the track bed plate of the track by means of the load detection pad device installed under the track bed plate, and acquiring corresponding force response signals; step S3, using a predetermined screening algorithm to screen out from the force signals a wheel-rail interaction time period in which a pair of wheels of the train interact with the track, and a target force signal within the wheel-rail interaction time period; step S4, screening out from the force response signals a target force response signal within the wheel-rail interaction time period; step S5, calculating an admittance spectrum based on the target force signal and the target force response signal, comparing the admittance spectrum with a predetermined reference admittance spectrum, and judging, based on the comparison result, whether the vibration reduction effect of the track is within a predetermined normal vibration reduction effect range.

[0006] The track vibration reduction effect monitoring method provided by the present invention may also have the following technical features, wherein step S3 includes the following sub-steps: step S3-1, converting the force signal into a Shannon envelope; step S3-2, scanning the Shannon envelope point by point, recording the peak value and time point of each peak point; step S3-3, screening out two target peak points that meet predetermined screening requirements from the multiple peak points, and the time period between the two target peak points is the wheel-rail action time period, wherein the predetermined screening requirements are: the peak value of the two target peak points is greater than a predetermined peak threshold, and the time difference between the time points of the two target peak points is greater than a predetermined difference threshold.

[0007] The rail vibration reduction effect monitoring method provided by the present invention may also have such technical features, wherein step S3-1 includes the following sub-steps: step S3-1-1, removing the DC component in the force signal; step S3-1-2, normalizing the force signal after removing the DC component; step S3-1-3, calculating the Shannon energy of the normalized force signal to obtain a Shannon energy sequence; step S3-1-4, smoothing the Shannon energy sequence; step S3-1-5, calculating the mean and variance of the corresponding Shannon energy based on the smoothed Shannon energy sequence; step S3-1-6, calculating the Shannon envelope based on the mean and the variance.

[0008] The rail vibration reduction effect monitoring method provided by the present invention may also have the following technical feature: in step S3-1-1, the DC component in the force signal is removed according to the following formula:

[0009]

[0010] N=Tf s

[0011] Where x(t) is the force signal, T is the duration of the force signal, and f s is the sampling frequency. In step S3-1-2, normalization is performed according to the following formula:

[0012]

[0013] In step S3-1-3, the Shannon energy is calculated according to the following formula:

[0014]

[0015] In step S3-1-4, set the average interval N o and overlap length L, and the Shannon energy sequence is smoothed according to the following formula:

[0016]

[0017] t n =t n-1 +L

[0018] In step S3-1-6, the Shannon envelope is calculated according to the following formula:

[0019]

[0020] Where, M(E s (n)) is the average Shannon energy, S(E s (n)) is the Shannon energy variance.

[0021] The track vibration reduction effect monitoring method provided by the present invention may also have the following technical features, wherein step S5 includes the following sub-steps:

[0022] Step S5-1: Calculate the 1 / 3 octave spectrum of the target force signal and the target force response signal respectively to obtain the force signal frequency spectrum F(f) and the force response signal frequency spectrum F(f). r (f); Step S5-2, based on the force signal frequency spectrum and the force response signal frequency spectrum, calculate the admittance spectrum Ω(f) according to the following formula:

[0023] Ω(f)=F r (f) / F(f)

[0024] Step S5-3, calculating the mean square error between the admittance spectrum Ω(f) and the reference admittance spectrum Ω0(f) according to the following formula:

[0025]

[0026] Step S5-4: determining whether the mean square error is between a predetermined lower threshold and a predetermined upper threshold. If the mean square error is negative, the vibration reduction effect is abnormal.

[0027] The track vibration reduction effect monitoring method provided by the present invention may also have such a technical feature, wherein step S5 includes the following sub-steps: step S5-1, calculating the 1 / 3 octave spectrum of the target force signal and the target force response signal respectively, and obtaining the force signal frequency spectrum F(f) and the force response signal frequency spectrum F r (f); Step S5-2, based on the force signal frequency spectrum and the force response signal frequency spectrum, calculate the admittance spectrum Ω(f) according to the following formula:

[0028] Ω(f)=F r (f) / F(f)

[0029] Step S5-3: Calculate the insertion loss of the track according to the following formula:

[0030] IL=20*logΩ(f) / Ω1(f)

[0031] Wherein Ω1(f) is a reference admittance spectrum obtained from a track without vibration reduction measures. Step S5-4 determines whether the insertion loss is between a predetermined lower threshold and an upper threshold. If the insertion loss is not within a predetermined lower threshold, it indicates that the vibration reduction effect is abnormal.

[0032] The rail vibration reduction effect monitoring method provided by the present invention may also have such technical features, wherein the load detection pad device includes: an upper cover plate, used to protect and accommodate the sensor; a sensor fixing plate, arranged between the base plate and the upper cover plate, having a plurality of sensor mounting grooves opening upward; and a plurality of pressure sensors, arranged in the sensor mounting grooves, whose detection ends abut against the bottom of the upper cover plate.

[0033] The present invention provides a track vibration reduction effect monitoring system, which is characterized by comprising: a plurality of load detection pad devices, respectively installed under the rails and under the roadbed of the track, respectively used to detect the load under the rails of the track and the force response under the roadbed, and obtain corresponding force signals and force response signals; a signal acquisition device, respectively electrically connected to the load detection pad device under the rails and the load detection pad device under the roadbed, and used to receive and collect the force signals and the force response signals when a train passes by; a calculation and analysis device, communicatively connected to the signal acquisition device, and used to calculate and analyze the force signals and the force response signals based on the collected force signals and the force response signals. The calculation and analysis are performed, and the method includes: a target force signal screening unit, which is used to screen out the wheel-rail action time period in which a pair of wheels of the train interact with the track and the target force signal within the wheel-rail action time period from the force signal based on a predetermined screening algorithm; a target force response signal screening unit, which is used to screen out the target force response signal within the wheel-rail action time period from the force response signal; an admittance spectrum generating unit, which is used to calculate and obtain an admittance spectrum based on the target force signal and the target force response signal; and an admittance spectrum comparison and judgment unit, which is used to compare the admittance spectrum with a predetermined reference admittance spectrum and judge whether the vibration reduction effect of the track is within a predetermined normal vibration reduction effect range based on the comparison result.

[0034] Functions and effects of the invention

[0035] According to the track vibration reduction effect monitoring method and system of the present invention, the load force signal under the track rail when a train passes by is detected by a load detection pad device under the track rail. At the same time, the force response signal under the track bed plate when a train passes by is detected by the same load detection pad device installed under the track bed plate. The corresponding admittance spectrum is calculated based on the force signal and the force response signal, and the vibration reduction effect of the track is judged based on the comparison results of the admittance spectrum. In traditional methods, the measurement results contain the characteristic costs of the excitation and structure, which cannot be effectively distinguished, resulting in a large uncertainty in the measurement results. However, the method of the present invention can effectively measure the accurate and actual vibration reduction effect of the track because it directly detects the load of the train during actual operation through the load detection pad device integrated under the track. Moreover, because the load detection pad device is integrated under the track and does not affect the passage of the train, the method of the present invention can be used for long-term monitoring of the vibration reduction effect of the track without stopping the line for detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a flow chart of the method for monitoring the track vibration reduction effect in the first embodiment of the present invention;

[0037] Figure 2 This is a structural block diagram of the track vibration reduction effect monitoring system in Example 1 of the present invention;

[0038] Figure 3 is a cross-sectional view of the track in Example 1 of the present invention;

[0039] Figure 4 This is an exploded view of the load detection pad device in Example 1 of the present invention;

[0040] Figure 5 is a cross-sectional view of the load detection pad device in the first embodiment of the present invention;

[0041] Figure 6 is a three-dimensional diagram of the pressure sensor in the first embodiment of the present invention;

[0042] Figure 7 is a perspective view of a load transfer column in Example 1 of the present invention;

[0043] Figure 8 is a three-dimensional diagram of the sensor fixing plate in the first embodiment of the present invention;

[0044] Figure 9 is a top view of the sensor fixing plate in the first embodiment of the present invention;

[0045] Figure 10 1 is a perspective view of the sensor fixing plate at different angles in the first embodiment of the present invention;

[0046] Figure 11 is a three-dimensional diagram of the upper cover plate in the first embodiment of the present invention;

[0047] Figure 12 yes Figure 5 An enlarged view of the portion within the middle frame A;

[0048] Figure 13 is a structural block diagram of the computing and analyzing device in the first embodiment of the present invention;

[0049] Figure 14 This is a flow chart of step S3 of the method for monitoring the track vibration reduction effect in the first embodiment of the present invention;

[0050] Figure 15 This is a flow chart of step S5 of the method for monitoring the track vibration reduction effect in the first embodiment of the present invention;

[0051] Figure 16 This is a flow chart of step S5 of the method for monitoring the track vibration reduction effect in the second embodiment of the present invention.

[0052] Reference numerals:

[0053] Track vibration reduction effect monitoring system 100; load detection pad device 10; upper cover plate 11; upper cover plate body 111; sensor limit groove 112; upper wiring groove 113; fastening screw mounting hole 114; sensor fixing plate 12; fixing plate body 121; sensor mounting groove 122; circular through hole 1221; support step 1222; lower wiring groove 123; line collection portion 1231; connector accommodating portion 1231a; branch portion 1232; countersunk hole 124; pressure sensor 13; detection end 131; cable 14; load transfer column 15; first column portion 151; second column portion 152; screw mounting hole Mounting hole 153; base plate 16; screw receiving hole 161; fixing plate fastening screw 17; base fixing screw 18; lower foundation 20; track bed plate 30; rail 40; signal acquisition device 50; calculation and analysis device 60; digital signal receiving unit 601; load data storage unit 602; load response data storage unit 603; comparison data storage unit 604; target force signal screening unit 605; target force response signal screening unit 606; admittance spectrum generating unit 607; admittance spectrum comparison and judgment unit 608; analysis side communication unit 609; analysis side control unit 610; communication device 70; monitoring terminal 71. DETAILED DESCRIPTION

[0054] In order to make the technical means, creative features, objectives and effects achieved by the present invention easier to understand, the rail vibration reduction effect monitoring method and system of the present invention are described in detail below with reference to embodiments and drawings.

[0055] <Example 1>

[0056] Figure 1 4 is a flow chart of the method for monitoring the track vibration reduction effect in this embodiment.

[0057] like Figure 1 As shown, this embodiment provides a method for monitoring the vibration reduction effect of a track, wherein a load detection pad device integrated under the track rail detects the load under the track rail to obtain a force signal, and a load detection pad device set under the track bed plate detects a corresponding force response signal, and the vibration reduction effect of the track is calculated and analyzed based on these two signals.

[0058] The following will first describe the corresponding sensor settings, and then combine these to describe the specific process steps of the monitoring method of this embodiment.

[0059] Figure 2 It is a structural block diagram of the track vibration reduction effect monitoring system in this embodiment.

[0060] like Figure 2 As shown, the track vibration reduction effect monitoring system 100 includes a load detection pad device 10 , a signal acquisition device 50 , a calculation and analysis device 60 , a communication device 70 and a plurality of monitoring terminals 71 .

[0061] The load detection pad device 10 is integrated into the track and is used to detect the track load when a train passes over it and obtain a corresponding force signal. The signal acquisition device 50 is used to collect the force signal and force response signal and transmit them to the calculation and analysis device 60. The calculation and analysis device 60 performs calculations and analysis based on the received force signal and force response signal to obtain the vibration reduction effect analysis results of the track. Through the communication device 70, multiple monitoring terminals 71 can obtain the measured force signal, force response signal, and vibration reduction effect analysis results of the track and display them.

[0062] Figure 3 2 is a cross-sectional view of the track in this embodiment.

[0063] like Figure 3 As shown, the load detection pad device 10 is directly installed in the track structure, one is installed under the rail 40, and the other is installed under the track bed plate 30. The rail 40 is a common I-shaped rail. The structure of the rail 40 is prior art and will not be repeated here.

[0064] In this embodiment, load detection pad devices 10 are installed under multiple pairs of rail pads under the rails 40 in the track. Simultaneously, identical load detection pad devices 10 are installed under the roadbed slab 30 under the rails 40. To correspond to the unfolding process of a wheel (i.e., the distance a wheel rolls when it contacts the rail once at every point on its circumference), load detection pad devices 10 are installed under at least seven pairs of rail pads under the rails 40 in the track.

[0065] Figure 4 It is a structural exploded view of the load detection pad device in this embodiment.

[0066] Figure 5 It is a side view with a partial cross-section of the load detection pad device in this embodiment.

[0067] like Figure 4 、 Figure 5As shown, the load detection pad device 10 includes an upper cover plate 11, a sensor fixing plate 12, multiple pressure sensors 13 and their cables 14, multiple load transfer columns 15, a base plate 16, multiple fixing plate fastening screws 17, and multiple base fixing screws 18. The multiple pressure sensors 13 are used to collect force signals from under the rails 40 and force response signals from under the track bed 30. The upper cover plate 11, sensor fixing plate 12, and base plate 16 are used to accommodate and fix the multiple pressure sensors 13 and their cables 14. The load transfer columns 15 are installed below each pressure sensor 13 to transfer load and improve the stability of the pressure sensors 13. Since the upper cover plate 11, sensor fixing plate 12, and base plate 16 are designed based on the structure of the pressure sensors 13 and their cables 14, the structure of the pressure sensors 13 and their cables 14 will be described below.

[0068] Figure 6 3D is a perspective view of the pressure sensor and its cable in this embodiment.

[0069] like Figure 6 As shown, the pressure sensor 13 is cylindrical in shape as a whole, with its detection end 131 located in the upper middle part, and its side wall is connected to a corresponding cable 14 for power supply and outputting a detection signal (ie, an analog pressure signal). Figure 6 Only a short section of cable 14 connected to the pressure sensor 13 is shown. In fact, the cable 14 extends out of the load dynamic monitoring pad device 10 and is connected to the above-mentioned signal acquisition device 50. In addition, the multiple cables 14 in the load dynamic monitoring pad device 10 need to be combined into a single line through an adapter, and then further connected to the signal acquisition device 50, such as Figure 2 shown.

[0070] Figure 7 3D is a perspective view of the load transfer column in this embodiment.

[0071] like Figure 7 As shown, the load transfer column 15 comprises an integrally formed first column portion 151 and a second column portion 152, both of which are cylindrical. The diameter of the first column portion 151 is larger than that of the second column portion 152, forming a stepped structure at the connection between the two. A through screw mounting hole 153 is defined in the center of the load transfer column 15. The diameter of the screw mounting hole 153 gradually increases toward the end of the second column portion 152. The base fixing screw 18 is a countersunk screw, and the shape of the screw mounting hole 153 matches the base fixing screw 18.

[0072] Figure 8 、 Figure 9 They are respectively a three-dimensional view and a top view of the sensor fixing plate in this embodiment, Figure 10 3D images of the sensor fixing plate at different angles in this embodiment.

[0073] like Figures 8-10 As shown, the sensor fixing plate 12 is a steel plate, including a fixing plate body 121 , a plurality of sensor mounting grooves 122 , a lower wiring groove 123 , and a plurality of countersunk holes 124 .

[0074] The fixing plate body 121 is in a rectangular parallelepiped shape with four chamfered corners. The thickness of the fixing plate body 121 is 10 mm to 15 mm.

[0075] The sensor mounting groove 122 is a cylindrical hole, which is distributed at the corner or edge of the fixed plate body 121. Its diameter and depth match the pressure sensor 13. After installation, the sensor mounting groove 122 opens upward. In this embodiment, the number of sensor mounting grooves 122 is 6. Along the central axis of the fixed plate body 121 in the length direction, the 6 sensor mounting grooves 122 are symmetrically distributed on both sides, and the 3 sensor mounting grooves 122 on the same side are distributed at equal intervals. That is, when installed under the rail 40 and the roadbed plate 30, the 6 pressure sensors 13 are symmetrically distributed on both sides below the rail 40 and under the roadbed plate 30. Figure 10 As shown, the bottom of the sensor mounting groove 122 has a circular through hole 1221, the diameter of the circular through hole 1221 is slightly smaller than the inner diameter of the sensor mounting groove 122, and a circle of supporting steps 1222 is formed at the bottom of the sensor mounting groove 122 for supporting and limiting the load transfer column 15.

[0076] The lower cable trough 123 is used to accommodate and secure the cables 14 to prevent them from shifting during train travel, which could cause poor contact or fall off, affecting signal acquisition. The lower cable trough 123 is located on one surface of the fixed plate 121 and includes a cable collection portion 1231 and multiple branching portions 1232.

[0077] The cable hub 1231 is located in the middle of the fixed plate body 121 and extends along the length of the fixed plate body 121. Its cross-section is rectangular and is used to accommodate multiple cables 14. One end of the cable hub 1231 is connected to one side of the fixed plate body 121 in the longitudinal direction and has a connector accommodating portion 1231a at this end. The connector accommodating portion 1231a has a semicircular cross-section.

[0078] One end of each branch portion 1232 connects to a sensor mounting slot 122, and the other end connects to the cable hub 1231. Each branch portion 1232 extends along the width of the fixed plate 121, perpendicular to the cable hub 1231. The connection between the branch portion 1232 and the cable hub 1231 is chamfered to prevent damage to the cable 14 from the sharp corner. The branch portion 1232 also has a rectangular cross-section, smaller than the cross-section of the cable hub 1231.

[0079] Four countersunk holes 124 are arranged in groups of two at each end of the mounting plate 121 along its length. These are used to install fastening screws that secure the sensor mounting plate 12 to the upper cover 11. The nuts of the fastening screws fit into the countersunk holes 124, ensuring that the bottom surface of the sensor mounting plate 12 remains flat after installation.

[0080] Figure 11 It is a three-dimensional diagram of the upper cover plate in this embodiment.

[0081] like Figure 11 As shown, the upper cover plate 11 is made of steel and includes an upper cover plate body 111, a sensor limit slot 112, an upper wiring slot 113, and a fastening screw mounting hole 114. The upper cover plate body 111 is roughly rectangular with chamfered corners, and its length and width are consistent with the fixed plate body 121.

[0082] The sensor limiting groove 112 is used to install and limit the pressure sensor 13. It is a cylindrical groove that matches the pressure sensor 13, and its inner diameter is consistent with the sensor installation groove 122. After installation, the sensor limiting groove 112 opens downward.

[0083] The upper wiring trough 113 is also used to accommodate and fix the cables 14 , and its shape is consistent with that of the lower wiring trough 123 .

[0084] The fastening screw mounting holes 114 are used to install fastening screws. The distribution of the four fastening screw mounting holes 114 corresponds to the distribution of the four countersunk holes 124, so that the upper cover plate 11 and the sensor fixing plate 12 can be fixedly connected by the fastening screws.

[0085] like Figure 5 As shown, the base plate 16 is a rectangular parallelepiped steel plate with chamfered corners, and its length and width are consistent with the fixing plate body 121.

[0086] A plurality of screw receiving holes 161 are provided on both sides of the base plate 16 in the width direction for connecting and fixing the load transfer columns 15 fixedly installed in each sensor mounting slot 122. In this embodiment, there are six screw receiving holes 161, which are distributed corresponding to the six sensor mounting slots 122. After installation, the screw receiving holes 161 are located on the central axis of the corresponding sensor mounting slot 122. The diameter of the upper end of the screw receiving hole 161 (i.e., the end close to the sensor fixing plate 12) is smaller than the diameter of the lower end (i.e., the end close to the track bed plate 30 and the lower foundation 20). Figure 6 As shown, viewed from the side, the cross-section of the screw receiving hole 161 is trapezoidal, and can be connected with the screw mounting hole 153 at the bottom of the load transfer column 15 to form a countersunk hole-like structure. The base fixing screw 18 is installed in the countersunk hole-like structure, so after installing the base fixing screw 18, the bottom surface of the base plate 16 is still flat.

[0087] As mentioned above, the bottom of the sensor mounting groove 122 has a circular through hole 1221, and the second column portion 152 of the load transfer column 15 is embedded in the circular through hole 1221. In order to avoid damage to the pressure sensor 13 due to large load and small contact area, a base plate 16 made of steel and with a certain thickness is arranged below the sensor fixing plate 12 and below the load transfer column 15.

[0088] like Figure 5-6 As shown, the shapes and distribution of the multiple sensor retaining grooves 112 and upper wiring grooves 113 on one surface of the upper cover plate 11 correspond to the multiple sensor mounting grooves 122 and lower wiring grooves 123 on one surface of the sensor fixing plate 12. When installed together, the upper wiring grooves 113 and lower wiring grooves 123 can be spliced to form a connected wiring section, and the corresponding sensor retaining grooves 112 and sensor mounting grooves 122 can be spliced to form six sensor accommodating sections.

[0089] Figure 12 yes Figure 5 Enlarged view of the portion inside frame A.

[0090] like Figure 5 、 Figure 12 As shown, after installation, the six pressure sensors 13 and the six load transfer columns 15 are respectively embedded in the six sensor accommodating parts, and their cables 14 are accommodated in the wiring part. Among them, the bottom of the load transfer column 15 (that is, the bottom of its second column 152) is in contact with the base plate 16, and is fixed and laterally limited by the base fastening screws 18. The first column 151 of the load transfer column 15 is in contact with the support step 1222 at the bottom of the sensor mounting groove 122, and the second column 152 is embedded in the circular through hole 1221. The bottom of the pressure sensor 13 is in contact with the upper end of the load transfer column 15, and the detection end 131 at the upper end is in contact with the bottom of the sensor limiting groove 112, so that the pressure sensor 13 remains stable during the monitoring process.

[0091] The cable 14 of each pressure sensor 13 is accommodated in the wiring portion. Specifically, the cable 14 extends from the corresponding branch portion 1232 and converges to the collection portion 1231, and extends along the collection portion 1231, and finally extends from one side of the length direction of the fixed plate body 121. The adapter connected to the cable 14 is embedded and fixed in the adapter accommodation portion.

[0092] The signal acquisition device 50 includes a signal acquisition instrument and an analog-to-digital converter. The signal acquisition instrument is connected to the pressure sensor 13 via a cable and is used to acquire the analog signal measured by the pressure sensor 13. The analog-to-digital converter is connected to the signal acquisition instrument and is used to convert the acquired analog signal into a digital signal representing the pressure value.

[0093] Figure 13It is a structural block diagram of the computing and analyzing device of this embodiment.

[0094] like Figure 13 As shown, the computing and analyzing device 60 includes a digital signal receiving unit 601, a load data storage unit 602, a load response data storage unit 603, a comparison data storage unit 604, a target force signal screening unit 605, a target force response signal screening unit 606, an admittance spectrum generating unit 607, an admittance spectrum comparison and judgment unit 608, an analysis side communication unit 609, and an analysis side control unit 610 for controlling the above-mentioned units.

[0095] The digital signal receiving unit 601 is used to obtain the converted digital signal from the signal acquisition device 50, and record the corresponding acquisition time point, device number, channel number (indicating which pressure sensor 13 collected the data), etc. These signals are stored as load data and load response data in the load data storage unit 602 and the load response data storage unit 603 respectively.

[0096] The load data storage unit 602 is used to store load data, including pressure value, corresponding device number, channel number, acquisition time point and other information.

[0097] The load response data storage unit 603 is used to store load response signals, including force response values, corresponding device numbers, channel numbers, acquisition time points and other information.

[0098] The comparison data storage unit 604 is used to store reference data for comparison. In this embodiment, the reference data includes a reference admittance spectrum and multiple thresholds for comparison.

[0099] The target force signal screening unit 605 is used to screen out the time period when a pair of wheels of the train interact with the track and the target force signal within the time period from the load data (force signal) stored in the load data storage unit 602 based on a predetermined screening algorithm.

[0100] The target force response signal screening unit 606 is used to screen out the target force response signal within the time period screened by the target force signal screening unit 605 from the load response data (force response signal) stored in the load response data storage unit 603 .

[0101] The admittance spectrum generating unit 607 is used to generate a corresponding admittance spectrum based on the screened target force signal and target force response signal using a predetermined admittance spectrum generating algorithm.

[0102] The admittance spectrum comparison and judgment unit 608 is used to compare the generated admittance spectrum with the stored reference admittance spectrum, and judge whether the vibration reduction effect of the track is within a predetermined range based on the comparison result.

[0103] The analysis-side communication unit 609 is used to communicate with other devices.

[0104] The communication device 70 is connected to the computing and analyzing device 60. Multiple monitoring terminals 71 are wirelessly connected to the communication device 70. Therefore, personnel can obtain load data, load response data, and their computational analysis results through the monitoring terminals 71. The monitoring terminals 71 can be devices such as smartphones, tablet computers, and computers.

[0105] Before starting monitoring, the monitoring parameters must first be set, and the pressure sensor 13 must be calibrated and zeroed.

[0106] First, calibrate and calibrate a single pressure sensor 13. The output of pressure sensor 13 is a voltage value, which requires calibration and calibration to convert the measured voltage value into a force value. Before calibration, perform a baseline measurement under no-load conditions. Then, apply the rated force to pressure sensor 13. During the calibration process, the applied force must remain stable.

[0107] Then, set the monitoring parameters through the operation terminal. The monitoring parameters include data storage path, sampling rate, measurement time, etc. Parameters that are not set will use the preset default values.

[0108] Afterwards, before starting the measurement, all pressure sensors 13 are reset to zero to eliminate the influence of preload or background noise. Then, monitoring can begin.

[0109] like Figure 1 As shown, based on the above-mentioned track vibration reduction effect monitoring system 100, the track vibration reduction effect monitoring method of this embodiment specifically includes the following steps:

[0110] Step S1 : When a train passes by, the load under the rail 40 of the track is detected by the load detection pad device 10 installed under the rail 40 of the track, and the corresponding force signal is collected.

[0111] In this embodiment, the load detection pad device 10 includes six pressure sensors 13, so six channels of sub-rail force signals are collected and averaged, and the averaged force signal is used as the force signal for subsequent calculation and analysis.

[0112] Step S2: When the train passes by, the load detection pad device 10 installed under the track bed plate 30 is used to detect the force response under the track bed plate 30, and a corresponding force response signal is collected.

[0113] Step S3: Using a predetermined screening algorithm, a wheel-rail interaction time period in which a pair of wheels of the train interact with the track and a target force signal within the wheel-rail interaction time period are screened out from the collected force signals.

[0114] Figure 14This is a flow chart of step S3 of the method for monitoring the track vibration reduction effect in this embodiment.

[0115] like Figure 14 As shown, step S3 specifically includes the following sub-steps:

[0116] Step S3-1, converting the force signal into a Shannon envelope.

[0117] Step S3-1 specifically includes the following sub-steps:

[0118] Step S3-1-1, removing the DC component in the force signal:

[0119]

[0120] N=Tf s

[0121] Where x(t) is the force signal, T is the duration of the force signal, and f s is the sampling frequency.

[0122] Step S3-1-2, normalize the force signal after removing the DC component:

[0123]

[0124] Step S3-1-3, calculate the Shannon energy of the normalized force signal to obtain the Shannon energy sequence:

[0125]

[0126] Step S3-1-4, set the average interval N o And overlap length L, the Shannon energy sequence is smoothed:

[0127]

[0128] t n =t n-1 +L

[0129] Step S3-1-5, based on the smoothed Shannon energy sequence, calculate the corresponding Shannon energy mean M(E s (n)) and variance S(E s (n)).

[0130] Step S3-1-6, based on the mean and variance calculated in step S3-1-5, calculate the Shannon envelope:

[0131]

[0132] Step S3-2: Scan the Shannon envelope point by point, and record the peak value and time point of each peak point.

[0133] Step S3-3: two target peak points meeting preset screening requirements are selected from the multiple peak points. The time period between the two target peak points is the wheel-rail interaction time period.

[0134] Among them, when any two peaks exceed the predetermined peak threshold and the time difference between the two peaks (i.e., the position distance on the graph) is greater than the predetermined peak distance threshold, the time range of the two peaks is the time period when the wheel-rail interaction occurs when a pair of wheels passes through the load detection pad device 10, and this time period is filtered out.

[0135] Step S4: Filter out the target force response signal within the wheel-rail interaction time period from the collected force response signals.

[0136] Step S5: Calculate the admittance spectrum based on the target force signal obtained in step S3 and the target force response signal obtained in step S4.

[0137] Figure 15 This is a flow chart of step S5 of the method for monitoring the track vibration reduction effect in this embodiment.

[0138] like Figure 15 As shown, step S5 specifically includes the following sub-steps:

[0139] Step S5-1: Calculate the 1 / 3 octave spectrum of the target force signal and the target force response signal respectively to obtain the force signal frequency spectrum F(f) and the force response signal frequency spectrum F(f). r (f).

[0140] Step S5-2: Based on the force signal frequency spectrum and the force response signal frequency spectrum, the admittance spectrum Ω(f) is calculated according to the following formula:

[0141] Ω(f)=F r (f) / F(f)

[0142] The above formula is also called transfer function, which represents the characteristic admittance of the track. The characteristic admittance mainly reflects the characteristics of the track structure.

[0143] Step S5-3, calculating the mean square error between the admittance spectrum Ω(f) and the reference admittance spectrum Ω0(f) according to the following formula:

[0144]

[0145] The reference admittance spectrum is measured from a vibration-damping track with similar structure and parameters and ideal vibration-damping performance. RMS deviation is often used in probability statistics to measure the degree of statistical distribution. By calculating the RMS deviation between the admittance spectrum of the current track and the ideal vibration-damping track, the deviation between the two can be effectively measured, thereby determining the vibration-damping effectiveness of the current track.

[0146] Step S5-4, judging whether the mean square error calculated in step S5-3 is between the predetermined lower threshold and upper threshold. If the judgment is yes, the vibration reduction effect of the track is ideal; if the judgment is no, the vibration reduction effect of the track is abnormal and needs to be repaired.

[0147] In this embodiment, parts not described in detail are well-known technologies in the art.

[0148] Example 1 Function and Effect

[0149] According to the track vibration reduction effect monitoring method and system provided in this embodiment, the load under the track rail 40 when a train passes is detected by multiple pressure sensors 13 of the load detection pad device 10 installed under the track track slab 30, and a force signal is obtained. At the same time, the load detection pad device 10 installed under the track track slab 30 detects the force response signal under the track track slab 30 when a train passes. The corresponding admittance spectrum is calculated based on the force signal and the force response signal, and the track vibration reduction effect is determined based on the comparison of the admittance spectrum results. In traditional methods, the measurement results contain both the excitation and structural characteristic costs, which cannot be effectively distinguished, resulting in large uncertainty in the measurement results. However, the method of this embodiment directly detects the actual train load during operation through the load detection pad device 10 integrated under the track. Therefore, the method of this embodiment can effectively measure the accurate and actual track vibration reduction effect. Moreover, since the load detection pad device 10 is integrated under the track and does not affect the passage of trains, the method of the present invention can be used for long-term monitoring of track vibration reduction effect without stopping the line for testing.

[0150] In this embodiment, the wheel-rail interaction time period, the target force signal, and the target force response signal within that time period are filtered out from the collected sub-rail force signal and track force response signal. The admittance spectrum is then calculated based on the target force signal and the target force response signal. Because the admittance spectrum characterizes the track structure, it can be compared with a reference admittance spectrum obtained from a track with ideal vibration reduction to effectively determine the vibration reduction effect of the current track.

[0151] In this embodiment, after removing the DC component and normalizing the force signal, the Shannon energy method is used to extract the signal envelope. This method can reduce low-energy noise in the signal while enhancing the energy of medium- and high-intensity signals, facilitating subsequent computational analysis. Furthermore, the Shannon energy method eliminates the need for pre-estimation of noise and signal duration, making it more convenient.

[0152] In the embodiment, the sensor fixing plate 12 and the upper cover plate 11 of the load detection pad device 10 respectively have six sensor mounting grooves 122 and sensor limiting grooves 112, which can be combined to form a plurality of cylindrical mounting holes for mounting and limiting the pressure sensor 13, and a cylindrical load transfer column 15 is also installed under the pressure sensor 13. Therefore, when the train passes, the pressure sensor 13 can remain stable and detect an accurate rail force signal, which is beneficial to subsequent calculation and analysis.

[0153] <Example 2>

[0154] Figure 16 This is a flow chart of step S5 of the method for monitoring the track vibration reduction effect in this embodiment.

[0155] like Figure 16 As shown, compared with the first embodiment, the difference of the track vibration reduction effect monitoring method of this embodiment is that in step S5-3, the transfer function is logarithmized and converted into a decibel value to obtain the insertion loss representing the track vibration reduction effect:

[0156] IL=20*logΩ(f) / Ω1(f)

[0157] Where Ω(f) is the admittance spectrum calculated in step S4, and Ω1(f) is the reference admittance spectrum obtained from the track without vibration reduction measures.

[0158] In step S5-4, the calculated insertion loss is compared with a predetermined lower threshold and an upper threshold of the insertion loss to determine whether there is any abnormality in the vibration reduction effect of the track.

[0159] As mentioned above, insertion loss refers to the loss of load power caused by the insertion of components or devices at a certain point in the transmission system. Therefore, it can also be used to determine the vibration reduction effect of the vibration reduction track after adopting vibration reduction measures.

[0160] In this embodiment, other structures and process steps are the same as those in the first embodiment and will not be described again.

[0161] The above embodiments are only used to illustrate specific implementations of the present invention, and the present invention is not limited to the description scope of the above embodiments.

Claims

1. A method for monitoring the vibration reduction effect of a track, which is used to monitor the vibration reduction effect of the track, characterized in that: The following steps are involved: Step S1, when a train passes by, detecting the load under the rail by means of a load detection pad device installed under the rail of the track, and collecting a corresponding force signal, wherein the load detection pad device includes at least one pressure sensor; Step S2, when the train passes by, detecting the force response under the track bed plate by the load detection pad device installed under the track bed plate, and collecting a corresponding force response signal; Step S3, using a predetermined screening algorithm to screen out from the force signal a wheel-rail interaction time period in which a pair of wheels of the train interact with the track and a target force signal within the wheel-rail interaction time period; Step S4, filtering out a target force response signal within the wheel-rail interaction time period from the force response signal; Step S5: Calculate an admittance spectrum based on the target force signal and the target force response signal, compare the admittance spectrum with a predetermined reference admittance spectrum, and determine whether the vibration reduction effect of the track is within a predetermined normal vibration reduction effect range based on the comparison result. Step S3 includes the following sub-steps: Step S3-1, converting the force signal into a Shannon envelope; Step S3-2, scanning the Shannon envelope point by point, recording the peak value and time point of each peak point; Step S3-3, two target peak points that meet the predetermined screening requirements are screened out from the plurality of peak points, and the time period between the two target peak points is the wheel-rail interaction time period. The predetermined screening requirement is that the peak values of the two target peak points are greater than a predetermined peak threshold, and the time difference between the time points of the two target peak points is greater than a predetermined peak distance threshold. Step S3-1 includes the following sub-steps: Step S3-1-1, removing the DC component in the force signal; Step S3-1-2, normalizing the force signal after removing the DC component; Step S3-1-3, calculating the Shannon energy of the normalized force signal to obtain a Shannon energy sequence; Step S3-1-4, smoothing the Shannon energy sequence; Step S3-1-5, calculating the mean and variance of the corresponding Shannon energy based on the smoothed Shannon energy sequence; Step S3-1-6: Calculate the Shannon envelope based on the mean and the variance.

2. The method for monitoring track vibration reduction effect according to claim 1, characterized in that: in, In step S3-1-1, the DC component in the force signal is removed according to the following formula: N=Tf s Where x(t) is the force signal, T is the duration of the force signal, and f s is the sampling frequency, In step S3-1-2, normalization is performed according to the following formula: In step S3-1-3, the Shannon energy sequence is calculated according to the following formula: In step S3-1-4, set the average interval N o and overlap length L, and the Shannon energy sequence is smoothed according to the following formula: t n =t n-1 +L In step S3-1-6, the Shannon envelope is calculated according to the following formula: Where, M(E s (n)) is the average Shannon energy, S(E s (n)) is the Shannon energy variance.

3. The method for monitoring track vibration reduction effect according to claim 1, characterized in that: in, Step S5 includes the following sub-steps: Step S5-1: Calculate the 1 / 3 octave spectrum of the target force signal and the target force response signal respectively to obtain the force signal frequency spectrum F(f) and the force response signal frequency spectrum F(f). r (f); Step S5-2: Calculate the admittance spectrum Ω(f) based on the force signal frequency spectrum and the force response signal frequency spectrum according to the following formula: Ω(f)=F r (f) / F(f) Step S5-3, calculating the mean square error between the admittance spectrum Ω(f) and the reference admittance spectrum Ω0(f) according to the following formula: Step S5-4: determine whether the mean square error is between a predetermined lower threshold and a predetermined upper threshold. If the determination is negative, the vibration reduction effect of the track is abnormal.

4. The method for monitoring the track vibration reduction effect according to claim 1, Its characteristics are: in, Step S5 includes the following sub-steps: Step S5-1: Calculate the 1 / 3 octave spectrum of the target force signal and the target force response signal respectively to obtain the force signal frequency spectrum F(f) and the force response signal frequency spectrum F(f). r (f); Step S5-2: Calculate the admittance spectrum Ω(f) based on the force signal frequency spectrum and the force response signal frequency spectrum according to the following formula: Ω(f)=F r (f) / F(f) Step S5-3: Calculate the insertion loss of the track according to the following formula: IL=20*logΩ(f) / Ω1(f) Where Ω1(f) is the reference admittance spectrum obtained from the track without vibration reduction measures; Step S5-4: determining whether the insertion loss is between a predetermined lower threshold and a predetermined upper threshold. If the determination is negative, the vibration reduction effect is abnormal.

5. The method for monitoring the track vibration reduction effect according to claim 1, Its characteristics are: Wherein, the load detection pad device includes: An upper cover plate, used for protecting and accommodating the sensor; a sensor fixing plate, disposed between the base plate and the upper cover plate, and having a plurality of sensor mounting slots opening upward; and A plurality of pressure sensors are arranged in the sensor installation groove, and the detection ends of the pressure sensors are in contact with the bottom of the upper cover plate.

6. A track vibration reduction effect monitoring system for monitoring the vibration reduction effect of a track, characterized in that: include: a plurality of load detection pad devices, respectively installed under the rails and under the track bed, for detecting the load under the rails and the force response under the track bed to obtain corresponding force signals and force response signals, wherein the load detection pad devices include at least one pressure sensor; a signal acquisition device, electrically connected to the load detection pad device under the rail and the load detection pad device under the track bed plate, respectively, for receiving and collecting the force signal and the force response signal when a train passes by; A calculation and analysis device, communicatively connected to the signal acquisition device, for performing calculation and analysis based on the collected force signal and the force response signal, comprising: a target force signal screening unit, which screens out a wheel-rail interaction time period in which a pair of wheels of the train interact with the track and a target force signal within the wheel-rail interaction time period from the force signal based on a predetermined screening algorithm; a target force response signal screening unit, configured to screen out the target force response signal within the wheel-rail interaction time period from the force response signal; an admittance spectrum generating unit, configured to calculate an admittance spectrum based on the target force signal and the target force response signal; and The admittance spectrum comparison and judgment unit is used to compare the admittance spectrum with a predetermined reference admittance spectrum, and judge whether the vibration reduction effect of the track is within a predetermined normal vibration reduction effect range according to the comparison result. The target force signal screening unit performs screening in the following manner: converting the force signal into a Shannon envelope; Scanning the Shannon envelope point by point, recording the peak value and time point of each peak point; Two target peak points meeting predetermined screening requirements are selected from the plurality of peak points, and the time period between the two target peak points is the wheel-rail interaction time period. The predetermined screening requirement is that the peak values of the two target peak points are greater than a predetermined peak threshold, and the time difference between the time points of the two target peak points is greater than a predetermined peak distance threshold. The force signal is converted into the Shannon envelope as follows: removing a DC component from the force signal; Normalizing the force signal after removing the DC component; Calculating the Shannon energy of the normalized force signal to obtain a Shannon energy sequence; performing smoothing processing on the Shannon energy sequence; Based on the smoothed Shannon energy sequence, calculating the mean and variance of the corresponding Shannon energy; The Shannon envelope is calculated based on the mean and the variance.

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