A method and device for generating train simulation excitation signals in a water-rich stratum tunnel

Abstract

The present invention provides a method and device for generating a simulated excitation signal for a train in a water-rich stratum tunnel, which relates to the field of engineering test technology, including: obtaining train operating parameters, wheel-rail vibration waves, and track characteristic parameters; dividing the wheel-rail vibration waves into frequency bands and calculating the time delay, performing phase compensation on each frequency band according to the time delay and generating a composite waveform to obtain a first signal; performing frequency domain correction on the first signal according to the train operating parameters, adjusting the amplitude of each frequency band according to the normalized energy of each frequency band after correction to obtain a second signal; dividing the frequency bands of the second signal according to the track characteristic parameters, and determining the center frequency of each frequency band, performing phase compensation according to the impedance corresponding to the center frequency to obtain a third signal; generating a simulated excitation signal based on the third signal and the train operating parameters. The excitation signal generated by the present invention has the composite characteristics of high-frequency transient impact and low-frequency rigid body motion, and can provide high-fidelity excitation input for related tests of train vibration loads.

Description

Technical Field

[0001] The present invention relates to the field of engineering test technology, and in particular to a method and device for generating a train simulation excitation signal in a water-rich stratum tunnel. Background Art

[0002] Railway tunnel construction through extremely complex environments is accompanied by risks such as high ground stress, fault movement, groundwater seepage, acid ion corrosion, and freeze-thaw cycles. Furthermore, train operation generates vibration loads at the wheel-rail interface, which are transmitted through the track, roadbed, and lining to the ground and surrounding buildings. In these extreme environments, vibration loads not only cause mud and mud to bubble up in the tunnel, water seepage, and gushing, leading to corrosion and cracking of the lining structure, but also soil liquefaction. Uneven subsidence of the foundation exacerbates the risk of surrounding rock instability and damage to surrounding buildings. In the test device, vibration loads are simulated by electromagnetic exciters. Currently, the signal input to the electromagnetic exciter is directly from train vibration loads of different waveforms and amplitudes, which makes it difficult to accurately reproduce the vibration characteristics of train wheels under different train operating conditions. Summary of the Invention

[0003] The purpose of the present invention is to provide a method and device for generating a simulated excitation signal for a train in a water-rich stratum tunnel to improve the above-mentioned problem. To achieve the above-mentioned purpose, the technical solution adopted by the present invention is as follows:

[0004] In a first aspect, the present application provides a method for generating a train simulation excitation signal for a tunnel in a water-rich stratum, comprising:

[0005] Obtain train operation parameters, wheel-rail vibration waves and track characteristic parameters;

[0006] The wheel-rail vibration wave is divided into frequency bands and the time delay is calculated. Phase compensation is performed on each frequency band according to the time delay and a composite waveform is generated to obtain a first signal.

[0007] Performing frequency domain correction on the first signal according to the train operation parameters, and adjusting the amplitude of each frequency band according to the normalized energy of each frequency band after correction to obtain a second signal;

[0008] Dividing the frequency bands of the second signal according to the track characteristic parameters, determining the center frequency of each frequency band, and performing phase compensation according to the impedance corresponding to the center frequency to obtain a third signal;

[0009] A simulated excitation signal is generated based on the third signal and train operation parameters.

[0010] In a second aspect, the present application provides a device for generating a simulated excitation signal for a train in a water-rich stratum tunnel, comprising:

[0011] The first module is used to obtain train operation parameters, wheel-rail vibration waves and track characteristic parameters;

[0012] The second module is used to divide the wheel-rail vibration wave into frequency bands and calculate the time delay, perform phase compensation on each frequency band according to the time delay and generate a composite waveform;

[0013] The third module is used to perform frequency domain correction on the first signal according to the train operation parameters, and adjust the amplitude of each frequency band according to the normalized energy of each frequency band after correction to obtain a second signal;

[0014] The fourth module is used to divide the frequency bands of the second signal according to the track characteristic parameters, determine the center frequency of each frequency band, perform phase compensation according to the impedance corresponding to the center frequency, and obtain the third signal;

[0015] The fifth module is used to generate a simulated excitation signal based on the third signal and train operation parameters.

[0016] The beneficial effects of the present invention are:

[0017] The present invention retains the original vibration timing characteristics based on time delay compensation and composite waveform generation of wheel-rail vibration waves; secondly, it achieves operating condition adaptability through frequency domain correction and energy normalization driven by operating parameters; finally, it accurately reproduces the wheel-rail coupling dynamic response through phase optimization based on track impedance. The ultimately generated excitation signal has the composite characteristics of high-frequency transient impact and low-frequency rigid body motion, which significantly improves the physical authenticity of the simulated excitation signal and can provide high-fidelity excitation input for related tests on train vibration loads.

[0018] Other features and advantages of the present invention will be set forth in the following description, and in part will be apparent from the description, or may be learned by practicing embodiments of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 This is a flow chart of a method for generating a train simulation excitation signal in a water-rich stratum tunnel according to an embodiment of the present application;

[0021] Figure 2 This is a schematic diagram of the box structure of the test device according to the embodiment of the present application;

[0022] Figure 3 This is a schematic diagram of the structure of the test device of the embodiment of the present application;

[0023] Figure 4This is a schematic diagram of the bottom plate structure of the test device according to the embodiment of the present application;

[0024] Figure 5 This is a schematic diagram of the arrangement of the electromagnetic exciter of the test device according to the embodiment of the present application;

[0025] Figure 6 This is a schematic diagram of the mounting beam arrangement of the test device according to the embodiment of the present application;

[0026] Figure 7 This is a structural diagram of a device for generating a simulated excitation signal for a train in a water-rich stratum tunnel according to an embodiment of the present application.

[0027] Markings in the figure: 1. Box; 2. Acrylic plate; 3. Steel beam; 4. Pressure plate; 5. Tunnel model; 6. Reaction frame; 7. Hydraulic loading device; 8. Oil pump; 9. Oil pipeline; 10. Oil pressure gauge; 11. High-pressure water tank; 12. Water pump; 13. Air pump; 14. Flow stabilization device; 15. Pressure relief valve; 16. Water inlet pipe; 17. Air inlet pipe; 18. Air pressure gauge; 19. Water pressure gauge; 20. Mounting beam; 21. Water pipeline; 22. Air valve; 23. Water inlet valve; 24. Water delivery valve; 25. Camera; 26. First interface; 27. Second interface; 28. Third interface; 29. ​​Hydraulic telescopic arm; 30. Longitudinal force transmission beam; 31. Electromagnetic exciter; 32. Dynamic force sensor; 33. Force distribution beam; 34. First bolt; 35. Second bolt; 36. Pulley; 37. Ionic solution storage tank; 38. Proportional valve; 39. Bottom plate; 40. Liquid nitrogen coil; 41. Infrared heating plate; 100. First module; 200. Second module; 210. First division unit; 220. First calculation unit; 230. First generation unit; 300. Third module; 310. Second calculation unit; 320. Third calculation unit; 330. First processing unit; 340. Correction unit; 350. Second division unit; 360. Second processing unit; 370. Adjustment unit; 400. Fourth module; 410. Fourth calculation unit; 420. Third division unit; 430. Fifth calculation unit; 440. Third processing unit; 500. Fifth module. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0029] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0030] Example 1:

[0031] See also Figure 1 , this embodiment provides a method for generating a train simulation excitation signal in a water-rich stratum tunnel, comprising steps S100, S200, S300, S400 and S500;

[0032] S100, obtaining train operation parameters, wheel-rail vibration waves and track characteristic parameters;

[0033] The train operation parameters include train speed, wheel-rail contact geometry parameters, and axle load parameters;

[0034] The wheel-rail vibration wave is the measured vibration wave;

[0035] Track characteristic parameters include the wheel-rail impedance curve; the wheel-rail impedance curve is a curve that describes the impedance characteristics of the wheel-rail system at different frequencies. It uses frequency as the horizontal axis and impedance as the vertical axis. Its amplitude-frequency characteristics show how the impedance changes with frequency. The peak value corresponds to the resonance point of the system, and the valley value corresponds to the anti-resonance point.

[0036] S200, dividing the wheel-rail vibration wave into frequency bands and calculating the time delay, performing phase compensation on each frequency band according to the time delay and generating a composite waveform to obtain a first signal; the details are as follows:

[0037] The wheel-rail vibration wave is divided into frequency bands by wavelet transform or bandpass filtering to obtain multiple frequency bands;

[0038] Perform discrete wavelet transform (DWT) on the vibration signal and divide it into different frequency bands through multi-scale decomposition. Alternatively, design a Butterworth bandpass filter based on the wheel-rail vibration characteristics to divide it into low, medium, and high frequency bands.

[0039] The time delay of each frequency band is calculated based on the train operation parameters, and the time shift and phase rotation of each frequency band are performed according to the time delay to achieve phase compensation;

[0040] The uncorrected delay is calculated as:

[0041] ;

[0042] in, is the uncorrected delay, is the propagation distance, is the train speed, is the wave speed.

[0043] There is a dispersion phenomenon when vibration waves of different frequencies propagate in the track, so it is necessary to obtain the wave velocity values ​​corresponding to different frequency bands. The wave velocity values ​​are measured by preliminary vibration tests.

[0044] The phase-compensated signals of each frequency band are superimposed to generate a composite waveform.

[0045] The obtained first signal includes a representation of the signal in the time domain and a representation of the signal in the frequency domain.

[0046] S300, performing frequency domain correction on the first signal according to the train operation parameters, and adjusting the amplitude of each frequency band according to the normalized energy of each frequency band after correction to obtain a second signal;

[0047] S310, based on the wheel-rail contact parameters, calculate the contact spot size according to Hertz contact theory;

[0048] The wheel-rail contact parameters include wheel-rail geometric parameters and material parameters, such as elastic modulus and curvature radius. After obtaining the wheel-rail contact parameters, the contact spot size is calculated according to the Hertz formula. and , Indicates the length along the track direction, Indicates the length perpendicular to the track direction.

[0049] S320, determining a high-frequency cutoff frequency based on the contact spot size;

[0050] The high-frequency cutoff frequency refers to the highest frequency component in the vibration signal that can be effectively transmitted under the limitation of the contact spot size. Frequency components higher than the high-frequency cutoff frequency are usually attenuated or filtered out.

[0051] First, we need to calculate the cutoff wavelength:

[0052] ;

[0053] in, is the proportionality coefficient, usually 2; is the cut-off wavelength;

[0054] Calculate the high-frequency cutoff frequency:

[0055] ;

[0056] in, is the vibration wave propagation velocity, which is calculated from the wheel-rail material parameters; is the high frequency cutoff frequency.

[0057] S330, designing a low-pass filter according to the high-frequency cutoff frequency, and using the low-pass filter to process the first signal;

[0058] The high-frequency cutoff frequency obtained by the above calculation is used as the cutoff frequency to design a low-pass filter, and the time domain signal is used as input to attenuate the components with frequencies higher than the cutoff frequency and filter out the frequency components higher than the cutoff frequency.

[0059] S340: Perform Fourier transform on the processed first signal to obtain a frequency domain representation, apply a filter or a weighting function to correct the frequency domain representation, and obtain a corrected frequency domain signal.

[0060] Low-pass filtering often introduces phase distortion, especially near the cutoff frequency. To ensure continuity in the frequency domain response, the phase of the remaining components after filtering needs to be adjusted again, resulting in a smooth transition near the cutoff frequency. This adjustment can involve designing a compensation filter based on the desired compensation amount, or by applying a weighting function. Weighting functions are typically designed based on frequency characteristics or time domain masks, such as enhancing or suppressing phase adjustment in specific frequency bands or dynamically adjusting based on the local characteristics of the signal. The adjusted phase is then combined with the original amplitude to produce a corrected frequency domain signal.

[0061] S400, dividing the frequency bands of the second signal according to the track characteristic parameters, determining the center frequency of each frequency band, and performing phase compensation according to the impedance corresponding to the center frequency to obtain a third signal;

[0062] S410, performing frequency band division on the corrected frequency domain signal using spectral kurtosis analysis to obtain multiple frequency bands;

[0063] Spectral kurtosis is a measure of the non-Gaussianity (non-stationarity) of a signal in the frequency domain. It can identify transient characteristic frequencies in a signal and thus divide the signal into stationary and impulse frequency bands. The calculation formula for spectral kurtosis is:

[0064] ;

[0065] in, is the frequency domain representation of the signal, represents the expected or average operation, is the spectral kurtosis;

[0066] After calculating the spectral kurtosis, frequency bands of different categories can be automatically divided by setting a threshold or clustering algorithm (such as K-means clustering).

[0067] S430, performing frequency band energy normalization processing on multiple frequency bands to obtain normalized energy of each frequency band;

[0068] Frequency band energy normalization is used to unify the vibration energy of different frequency bands to the same scale. After normalization, the energy distribution of each frequency band can be compared and analyzed on the same scale, thereby more clearly analyzing the energy distribution characteristics of each frequency band and providing standardized input for subsequent vibration control and signal processing, thereby improving the stability and convergence of the algorithm.

[0069] Calculate the energy of each frequency band and the total energy of all frequency bands respectively, and process them through the Min-Max normalization method to obtain the normalized energy of each frequency band;

[0070] S440: Adjust the amplitude of each frequency band according to the normalized energy to obtain a second signal.

[0071] The amplitude of each frequency band is scaled according to the normalized energy of each frequency band (without changing the phase), and the adjusted amplitude is combined with the original phase to obtain the second signal.

[0072] S450, obtaining a time delay correction formula based on the wheel-rail impedance curve;

[0073] The wheel-rail impedance curve plots the frequency response characteristics with frequency as the horizontal axis (logarithmic or linear) and impedance amplitude (or phase) as the vertical axis.

[0074] Specifically, the impact test or vibration test can be performed using accelerometers and force sensors to measure the dynamic response of the track at different frequencies and calculate the frequency The impedance of the following:

[0075] ;

[0076] in is the applied force, is the vibration speed; is the angular frequency, which is different from the normal frequency The relationship is: ;

[0077] Perform frequency response analysis and derive the complex impedance: ;

[0078] is the real part, reflecting the energy consumption characteristics (damping effect) of the system, with the unit of N·s / m;

[0079] is the imaginary part, reflecting the energy storage characteristics (inertia or elasticity) of the system, with the unit of N·s / m;

[0080] Is an imaginary unit.

[0081] Wave speed in orbit Related to the real part of the impedance:

[0082] ;

[0083] in, represents the real part of the complex impedance; Characteristic impedance is the core parameter that describes the energy transfer characteristics when a wave propagates in a medium. Its physical essence is the inherent resistance of the medium to the transmission of vibration waves.

[0084] The uncorrected delay formula is:

[0085] ;

[0086] in, is the uncorrected delay, is the propagation distance, is the train speed, is the wave speed.

[0087] By introducing the impedance correction term, the delay correction formula is:

[0088] ;

[0089] S460: Obtain an impedance mutation point based on the wheel-rail impedance curve, and divide the second signal into low, medium, and high frequency bands based on the impedance mutation point;

[0090] By analyzing the complex impedance The second-order derivative of is used to identify the characteristic frequency segmentation threshold. When the second-order derivative is flat, it is divided into the low-frequency band. When the second-order derivative fluctuates significantly, it is divided into the medium-frequency band. When the second-order derivative approaches 0, it is divided into the high-frequency band.

[0091] S470, determining the center frequencies of the low, medium, and high frequency bands through wavelet transform, and substituting each center frequency into a delay correction formula to obtain a corrected delay for each frequency band;

[0092] After the frequency bands are divided, the center frequency can be determined by extracting the energy extreme points of the wavelet coefficients in each frequency band.

[0093] Calculate the corresponding angular frequency based on the center frequency , and then substitute it into the delay correction formula to get the corrected delay for each frequency band .

[0094] S480: Perform delay processing on each frequency band of the second signal according to the corrected time delay to obtain a third signal.

[0095] S500: Generate a simulated excitation signal based on the third signal and train operation parameters.

[0096] This step involves performing coordinate mapping on the generated third signal based on the train's movement parameters, converting the trajectory of the dynamically changing signal in the time-space domain into an expression in a specific coordinate system. Using the equation of motion, the time t is mapped to the position of the signal, accurately reconstructing the changes in the moving wheel-rail.

[0097] Based on the above method, this embodiment also provides a test device for simulating the dynamic response of the tunnel structure and surrounding rock under high ground stress-seepage. Figure 2 and Figure 3 The test apparatus includes a seepage model box 1 filled with model soil, with transparent acrylic panels 2 on the sides and a movable pressure plate 4 on the top. The outside is reinforced with steel beams 3. A freeze-thaw cycle subsystem, coordinated by a liquid nitrogen coil 40 and an infrared heating plate 41, is installed on the bottom plate 39 of the box 1. The box 1 is connected to the high-ground stress loading subsystem via a reaction frame 6, to the high-pressure seepage subsystem via a water pipe 21, and to the dynamic loading subsystem via a mounting beam 20. A multi-field coordinated monitoring subsystem allows for real-time monitoring of the comprehensive response of the structure and surrounding rock during the test.

[0098] Taking into account the fluid-structure interaction boundary effects, the model box 1 is 200 cm long, 100 cm wide, and 160 cm high. To facilitate seepage observation, the sides of the box 1 are lined with 2 cm thick acrylic panels 2, reinforced with steel beams 3 on the outside, and topped with a steel bearing plate 4. Symmetrical tunnel cross-sectional holes are opened on the front and rear ends of the box 1 to accommodate the tunnel model 5, with a diameter of 25 cm. The model box 1 is filled with compacted test model soil. The acrylic panels 2 on the sides of the box 1 are bonded with waterproof glass glue. The front and rear acrylic panels 2 can be removed and replaced to accommodate tunnel models 5 of different cross-sectional shapes and quantities to simulate different tunnel types.

[0099] The tunnel model 5 is composed of prefabricated segments, with a roadbed arranged in its length direction and tracks installed on the roadbed.

[0100] The high ground stress loading subsystem includes an oil pump 8, an oil pipeline 9, an oil pressure gauge 10, a reaction frame 6, a hydraulic loading device 7, and a pressure plate 4. The hydraulic loading device 7 is connected to the oil pump 8 through the oil pipeline 9, and the oil pressure gauge 10 monitors the oil pressure. The upper end of the hydraulic loading device 7 is connected to the reaction frame 6, and the reaction force and pressure are applied through the reaction frame 6. The lower end is connected to the pressure plate 4 to simulate ground stress at different burial depths.

[0101] The high-pressure seepage subsystem includes a high-pressure water tank 11, a water pump 12, an air pump 13, a flow stabilizing device 14, a pressure relief valve 15, a water inlet pipe 16, an air inlet pipe 17, an air pressure gauge 18, a water pressure gauge 19, a water supply pipe 21, an air valve 22, a water inlet valve 23, a water supply valve 24, an ion solution storage tank 37, and a proportional valve 38. The high-pressure water tank 11 is filled with water containing a fluorescent dye, and a pressure relief valve 15 is installed at the upper end to regulate the water tank pressure. It is connected to the water pump 12 through a water inlet pipe 16 and to the air pump 13 through an air inlet pipe 17. An ion solution storage tank 37 is provided downstream of the high-pressure water tank 11, which is connected through a proportional valve 38 and connected to the model box body 1 through a water supply pipe 21 on the other side. A water pressure gauge 19 is provided on the water supply pipe 21 to monitor the water pressure. By combining different water supply modes of the first interface 26, the second interface 27, and the third interface 28, various seepage modes such as vertical seepage, horizontal seepage, unilateral seepage, and bilateral seepage can be simulated to achieve pulsed injection of corrosive solutions and dynamic tracking of the seepage path.

[0102] The flow stabilizing device 14 is installed between the interior of the model box and the interface of the water pipe 21, and includes a perforated baffle and geotextile. Gravel is filled between the perforated baffle and the side wall of the model box and divided into multiple layers with geotextile, which can simulate uniform and stable seepage boundary conditions.

[0103] The power loading system includes a mounting beam 20, a hydraulic telescopic arm 29, a longitudinal force transmission beam 30, an electromagnetic exciter 31, a dynamic force sensor 32, and a force distribution beam 33. Figure 5 and Figure 6 The mounting beam 20 is secured to the front and rear ends of the model box 1 via first bolts 34. A slot is defined at its lower end. A hydraulic telescopic arm 29 is connected to the mounting beam 20 via a pulley 36 within the slot. The hydraulic telescopic arm 29 can move horizontally along the slot and can also be extended vertically for quick and easy position adjustment. A longitudinal force transmission beam 30 is secured to the lower end of the hydraulic telescopic arm 29. Multiple sets of electromagnetic exciters 31 are mounted to the longitudinal force transmission beam 30 via second bolts 35 along the length of the tunnel model 5. Dynamic force sensors 32 are mounted at the bottom of the electromagnetic exciters 31. Force distribution beams 33 distribute the force evenly below the dynamic force sensors 32. The power loading system also includes a computer, a signal generator, and a power amplifier. The computer is electrically connected to the electromagnetic exciters 31. The signal generator and power amplifier are located outside the model box. The hydraulic telescopic arm 29 is dynamically connected to the mounting beam 20 via a pulley 36. The vertical hydraulic drive and radial angle adjustment mechanism of the hydraulic telescopic arm 29 work together to precisely control the three-dimensional coordinates of the excitation point.

[0104] The power loading system also includes a digital control unit, which includes an industrial control computer, a multi-channel signal generator and a power amplifier module; among them, the industrial control computer and the electromagnetic exciter 31 form a closed-loop control system with a built-in time-space coupling control algorithm, that is, the above-mentioned method of generating analog excitation signals, to accurately reconstruct the moving wheel-rail force time history curve.

[0105] The multi-field coordinated monitoring subsystem includes a seepage monitoring system, an earth pressure monitoring system, a structural corrosion and cracking monitoring system, and a power monitoring system.

[0106] The dynamic monitoring system includes a dynamic force sensor 32, an acceleration sensor, a dynamic strain sensor, and a signal acquisition device. The acceleration sensor and the dynamic strain sensor are electrically connected to the dynamic force sensor 32, and the signal acquisition device is connected to a computer. The acceleration sensor is buried in the soil layer, and the dynamic strain sensor is pasted on the tunnel model 5.

[0107] The seepage monitoring system includes a pore-water pressure gauge, a signal acquisition device, a computer, and a camera 25. The pore-water pressure gauge is buried in the soil layer, while the signal acquisition device and computer are electrically connected and located outside the model box. The camera 25 is mounted at the front end of the tunnel model 5 and can capture traces of fluorescent dye in the test water, enabling visual monitoring of the seepage field.

[0108] The soil pressure monitoring system includes a soil pressure box, a signal acquisition device and a computer. The soil pressure box is buried in the soil layer, and the signal acquisition device and the computer are electrically connected and placed outside the model box.

[0109] This test device can achieve pulsed injection of corrosive solutions and accurate simulation and dynamic tracking of various seepage paths through a high-pressure seepage system with coordinated air-hydraulic pressure control containing a chemical solution tank, combined with fluorescence tracing and visual monitoring technology.

[0110] The test device can embed a liquid nitrogen coil 40 and an infrared heating plate 41 at the bottom of the model box to achieve rapid temperature change and accurately simulate the freeze-thaw cycle.

[0111] Example 2:

[0112] See also Figure 7 This embodiment provides a device for generating a train simulation excitation signal for a tunnel in a water-rich stratum, comprising:

[0113] The first module 100 is used to obtain train operation parameters, wheel-rail vibration waves and track characteristic parameters;

[0114] The second module 200 is used to divide the wheel-rail vibration wave into frequency bands and calculate the time delay, perform phase compensation on each frequency band according to the time delay and generate a composite waveform to obtain a first signal;

[0115] The third module 300 is configured to perform frequency domain correction on the first signal according to the train operation parameters, and adjust the amplitude of each frequency band according to the normalized energy of each frequency band after correction to obtain a second signal;

[0116] The fourth module 400 is configured to divide the frequency bands of the second signal according to the track characteristic parameters, determine the center frequency of each frequency band, and perform phase compensation according to the impedance corresponding to the center frequency to obtain a third signal.

[0117] The fifth module 500 is configured to generate a simulated excitation signal based on the third signal and train operation parameters.

[0118] As an optional implementation manner, the train operation parameter includes speed; the second module 200 includes:

[0119] The first division unit 210 is used to divide the wheel-rail vibration wave into frequency bands by wavelet transform or bandpass filtering to obtain multiple frequency bands;

[0120] A first calculation unit 220 is configured to calculate the time delay of each frequency band based on the train operation parameters, and perform time shift and frequency domain phase rotation on each frequency band according to the time delay;

[0121] The first generating unit 230 is configured to superimpose the phase-compensated signals of each frequency band to generate a composite waveform.

[0122] As an optional implementation manner, the train operation parameter includes a wheel-rail contact parameter; the third module 300 includes:

[0123] A second calculation unit 310 is configured to calculate the contact spot size based on the wheel-rail contact parameters and the Hertz contact theory;

[0124] A third calculation unit 320 is configured to determine a high frequency cutoff frequency based on the contact patch size;

[0125] A first processing unit 330 is configured to design a low-pass filter according to the high-frequency cutoff frequency, and process the first signal using the low-pass filter;

[0126] The correction unit 340 is configured to perform Fourier transform on the processed first signal to obtain a frequency domain representation, and apply a filter or a weighting function to correct the frequency domain representation to obtain a corrected frequency domain signal.

[0127] As an optional implementation, the third module 300 includes:

[0128] The second dividing unit 350 is configured to divide the corrected frequency domain signal into frequency bands by using spectral kurtosis analysis to obtain a plurality of frequency bands;

[0129] The second processing unit 360 is configured to perform frequency band energy normalization processing on the multiple frequency bands to obtain normalized energy of each frequency band;

[0130] The adjustment unit 370 is configured to adjust the amplitude of each frequency band according to the normalized energy to obtain a second signal.

[0131] As an optional embodiment, the track characteristic parameter includes a wheel-rail impedance curve; the fourth module 400 includes:

[0132] A fourth calculation unit 410 is configured to obtain a time delay correction formula based on the wheel-rail impedance curve;

[0133] A third dividing unit 420 is configured to obtain an impedance mutation point based on the wheel-rail impedance curve, and divide the second signal into low, medium and high frequency bands based on the impedance mutation point;

[0134] A fifth calculation unit 430 is configured to determine the center frequencies of the low, medium, and high frequency bands through wavelet transform, and substitute each center frequency into a delay correction formula to obtain a corrected delay for each frequency band;

[0135] The third processing unit 440 is configured to perform delay processing on each frequency band of the second signal according to the corrected time delay to obtain a third signal.

[0136] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device comprising the element.

[0137] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A method for generating a train simulation excitation signal in a water-rich stratum tunnel, characterized in that: include: Obtain train operation parameters, wheel-rail vibration waves and track characteristic parameters; The train operation parameters include speed and wheel-rail contact parameters; the track characteristic parameters include wheel-rail impedance curve; The wheel-rail vibration wave is divided into frequency bands and the time delay is calculated. Phase compensation is performed on each frequency band according to the time delay and a composite waveform is generated to obtain a first signal. include: Calculate the time delay of each frequency band based on the train speed: ； in, is the uncorrected time delay, d is the propagation distance, is the train speed, is the wave speed; Performing frequency domain correction on the first signal according to the train operation parameters, and adjusting the amplitude of each frequency band according to the normalized energy of each frequency band after correction to obtain a second signal, including: Based on the wheel-rail contact parameters, the contact patch size is calculated according to the Hertz contact theory; Determine the high-frequency cutoff frequency based on the contact patch size; Designing a low-pass filter according to the high-frequency cutoff frequency, and processing the first signal using the low-pass filter; Performing Fourier transform on the processed first signal to obtain a frequency domain representation, and applying a filter or a weighting function to modify the frequency domain representation to obtain a modified frequency domain signal; Dividing the frequency bands of the second signal according to the track characteristic parameters, determining the center frequency of each frequency band, and performing phase compensation according to the impedance corresponding to the center frequency to obtain the third signal; comprising: The time delay correction formula is obtained based on the wheel-rail impedance curve; Obtaining an impedance mutation point based on the wheel-rail impedance curve, and dividing the second signal into low, medium, and high frequency bands based on the impedance mutation point; The center frequencies of the low, medium, and high frequency bands are determined by wavelet transform, and each center frequency is substituted into the delay correction formula to obtain the corrected delay of each frequency band; performing delay processing on each frequency band of the second signal according to the corrected time delay to obtain a third signal; A simulated excitation signal is generated based on the third signal and train operation parameters.

2. The method for generating a train simulation excitation signal for a water-rich stratum tunnel according to claim 1, characterized in that: The train operation parameters include speed; dividing the wheel-rail vibration wave into frequency bands and calculating the time delay, performing phase compensation on each frequency band according to the time delay and generating a composite waveform, including: The wheel-rail vibration wave is divided into frequency bands by wavelet transform or bandpass filtering to obtain multiple frequency bands; Calculate the time delay of each frequency band based on the train operation parameters, and perform time shift and frequency domain phase rotation on each frequency band according to the time delay; The phase-compensated signals of each frequency band are superimposed to generate a composite waveform.

3. The method for generating a train simulation excitation signal for a water-rich stratum tunnel according to claim 1, characterized in that: Performing frequency domain correction on the first signal according to the train operation parameters, and adjusting the amplitude of each frequency band according to the normalized energy of each frequency band after correction to obtain a second signal, including: The spectral kurtosis analysis is used to divide the corrected frequency domain signal into frequency bands to obtain multiple frequency bands; Performing frequency band energy normalization processing on multiple frequency bands to obtain normalized energy of each frequency band; The amplitude of each frequency band is adjusted according to the normalized energy to obtain a second signal.

4. A device for generating a train simulation excitation signal in a water-rich stratum tunnel, characterized in that: include: The first module is used to obtain train operation parameters, wheel-rail vibration waves and track characteristic parameters; The train operation parameters include speed and wheel-rail contact parameters; the track characteristic parameters include wheel-rail impedance curve; The second module is used to divide the wheel-rail vibration wave into frequency bands and calculate the time delay, perform phase compensation on each frequency band according to the time delay and generate a composite waveform to obtain the first signal; include: Calculate the time delay of each frequency band based on the train speed: ； in, is the uncorrected time delay, d is the propagation distance, is the train speed, is the wave speed; The third module is used to perform frequency domain correction on the first signal according to the train operation parameters, and adjust the amplitude of each frequency band according to the normalized energy of each frequency band after correction to obtain a second signal; The third module includes: a second calculation unit, configured to calculate the contact spot size based on the wheel-rail contact parameters and in accordance with the Hertz contact theory; a third calculation unit, configured to determine a high frequency cutoff frequency based on a contact patch size; a first processing unit, configured to design a low-pass filter according to a high-frequency cutoff frequency, and process the first signal using the low-pass filter; a correction unit for performing a Fourier transform on the processed first signal to obtain a frequency domain representation, and applying a filter or a weighting function to correct the frequency domain representation to obtain a corrected frequency domain signal; The fourth module is used to divide the frequency bands of the second signal according to the track characteristic parameters, determine the center frequency of each frequency band, perform phase compensation according to the impedance corresponding to the center frequency, and obtain the third signal; The fourth module includes: a fourth calculation unit, configured to obtain a time delay correction formula based on the wheel-rail impedance curve; a third dividing unit, configured to obtain an impedance mutation point based on the wheel-rail impedance curve, and divide the second signal into low, medium and high frequency bands based on the impedance mutation point; a fifth calculation unit, configured to determine the center frequencies of the low, medium, and high frequency bands by wavelet transform, and substitute each center frequency into a delay correction formula to obtain a corrected delay for each frequency band; a third processing unit, configured to perform delay processing on each frequency band of the second signal according to the corrected time delay to obtain a third signal; The fifth module is used to generate a simulated excitation signal based on the third signal and train operation parameters.

5. The device for generating a train simulation excitation signal for a water-rich stratum tunnel according to claim 4, characterized in that: The train operation parameter includes speed; the second module includes: The first division unit is used to divide the wheel-rail vibration wave into frequency bands by wavelet transform or bandpass filtering to obtain multiple frequency bands; A first calculation unit is configured to calculate the time delay of each frequency band based on the train operation parameters, and perform time shift and frequency domain phase rotation on each frequency band according to the time delay; The first generating unit is used to superimpose the phase-compensated signals of each frequency band to generate a composite waveform.

6. The device for generating a train simulation excitation signal for a water-rich stratum tunnel according to claim 4, characterized in that: The third module includes: The second division unit is used to divide the corrected frequency domain signal into frequency bands by using spectral kurtosis analysis to obtain multiple frequency bands; a second processing unit, configured to perform frequency band energy normalization processing on the multiple frequency bands to obtain normalized energy of each frequency band; The adjustment unit is used to adjust the amplitude of each frequency band according to the normalized energy to obtain a second signal.

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