Rock testing device and method based on laser calibration excitation compensation

Abstract

The invention provides a rock testing device and method based on laser calibration excitation compensation, and relates to the technical field of rock physical testing, and the rock testing device comprises a rock sample clamping part which is used for clamping a rock sample; the strain testing part is used for being arranged on the surface of the rock sample; the output end of the vibration exciter is in contact with the rock sample clamping component; the driving module is connected with the vibration exciter and is used for inputting an electric signal to the vibration exciter so as to drive the vibration exciter to operate; the laser vibration meter is used for testing the acceleration of the output end of the vibration exciter during no-load operation under different operation frequencies; the problem that in the prior art, in a large frequency range, the testing precision of rock physical testing under different frequencies is poor is solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of rock physical testing, and more specifically, relates to a rock testing device and method based on laser calibration and vibration excitation compensation. Background Art

[0002] Seismic rock physics builds a bridge connecting seismic information with the most basic parameters of rocks. It is the physical basis for pre-stack reservoir prediction and the link connecting seismology and reservoir engineering. The research results of rock physical properties are mainly as follows: on the one hand, it lays a physical foundation for extracting the properties of underground rocks and their saturated fluids from seismic wave data, that is, the seismic inversion process; on the other hand, understanding the relationship between seismic wave characteristics and rock and fluid properties can help us simulate the propagation of seismic waves under complex surfaces, that is, the seismic forward modeling process. The research objectives of traditional rock physics are microscopic, mainly analyzing the rock mineral composition, skeleton, and fluid properties at the pore scale, as well as the influence of temperature and pressure conditions on rock physical properties; while well logging analysis data is of high resolution. Although its resolution is lower compared to microscopic feature analysis, its attention is mainly focused on parameters such as porosity, permeability, and saturation, and rarely pays attention to the influence of different physical properties and fluid states on elastic parameters; seismic and seismic exploration research mainly starts from the scale of oil fields and geological structures, with very low resolution and less attention to the influence of lithology and fluids on seismic imaging. Therefore, multi-scale and multi-disciplinary data fusion is one of the future research directions. The most important thing in rock physics model research is to study the role and contribution of the physical properties of each component forming the skeleton and fluid to the overall physical properties of the rock, and to make the established rock physics model be able to accurately characterize the actual rock reservoir as much as possible.

[0003] Measuring the acoustic properties of rocks, such as longitudinal and transverse wave velocities and acoustic attenuation coefficients, is a basic research work in geophysical applied research. Due to the differences in the sedimentary environment of rocks and the properties of the parent rocks forming the rocks, there are significant differences in the lithology of rocks, showing non-uniformity and anisotropy. These characteristics of rocks have caused many problems in the measurement of rock physical parameters, especially in the measurement of acoustic characteristics, which have not been solved yet; such as the measurement of sound velocity and acoustic attenuation of small rock samples in the low-frequency band (1 Hz - 20 KHz), the measurement of acoustic parameters of loose porous rocks and strongly anisotropic rocks, etc.

[0004] Therefore, accurately measuring these parameters within the field application frequency band in the laboratory is of great significance for understanding the properties of underground rocks using seismic exploration and acoustic logging data, and studying the variation characteristics of seismic facies and well logging facies with frequency. Directly conducting conventional tests on low-frequency (field seismic exploration and logging frequency band) rock acoustic parameters is a long-term goal pursued by rock physicists.

[0005] The stress-strain method is also an important type of low-frequency testing technology. The stress-strain measurement technology obtains the acoustic properties of rock samples by directly recording the forced deformation applied to the rock samples. In 1981, Spencer first used the stress-strain test principle to conduct experiments on the wave velocity and attenuation of rocks under low-frequency conditions. This method can measure the modulus changes caused by fluctuations when different harmonics with frequencies ranging from 4 to 400 Hz pass through the rock sample under the condition that the strain is close to 10 -7, and then calculate the longitudinal and transverse wave velocities of the rock sample.

[0006] Due to different sedimentary environments and diagenetic processes, the research objects of rock physics will form different rock types and there are also many different pore structures. These factors lead to great differences in the elastic properties of rocks. These characteristics of rocks bring many unsolved problems to the measurement of rock acoustic parameters, such as the measurement of attenuation, sound velocity sum in low frequency and small rock samples. Generally, the acoustic parameters of rocks containing fluids change with frequency. When using seismic exploration to detect fluids in rock pores, it is often necessary to combine geophysical data in different frequency bands, but these data are essentially different in frequency. It is very necessary to study the quantitative relationship of geophysical data at different frequencies. Therefore, accurately measuring these parameters has important theoretical and practical significance for understanding the properties of underground rocks, fluid identification, and seismic matching of various geophysical data.

[0007] The current rock testing devices are difficult to accurately conduct rock physics tests at different frequencies within a large frequency range, and the test accuracy is difficult to meet the research requirements. Summary of the Invention

[0008] The purpose of the present invention is to provide a rock testing device and method based on laser calibration and vibration excitation compensation to solve the problem of poor test accuracy for rock physics tests at different frequencies within a large frequency range in the prior art.

[0009] To achieve the above purpose, the present invention provides a rock testing device based on laser calibration and vibration excitation compensation, including:

[0010] A rock sample clamping component for clamping a rock sample;

[0011] A strain testing component for being arranged on the surface of the rock sample;

[0012] A vibration exciter whose output end is in contact with the rock sample clamping component;

[0013] A driving module connected to the vibration exciter for inputting an electrical signal to the vibration exciter to drive the vibration exciter to operate;

[0014] A laser vibrometer, which is used to test the acceleration of the output end of the exciter when it operates without load at different operating frequencies.

[0015] Optionally, it further includes a compensation module, which includes a data receiving unit, a data processing unit, and a data output unit;

[0016] The data receiving unit is used to receive the test results of the exciter when it operates without load at different operating frequencies, and generate relationship data between acceleration and operating frequency;

[0017] The data processing unit is used to generate relationship data between the output amplitude of the drive module and the operating frequency that makes the acceleration of the output end of the exciter consistent at different operating frequencies based on the relationship data between acceleration and operating frequency;

[0018] The data output unit is used to transmit the relationship data between the output amplitude of the drive module and the operating frequency to the drive module to compensate the electrical signal output by the drive module.

[0019] Optionally, it further includes a base and a top plate. The base is connected to the top plate through a connecting rod. The exciter is connected to the base, and the rock sample clamping component is arranged between the exciter and the top plate.

[0020] Optionally, an installation chamber is arranged inside the base. The exciter is installed in the installation chamber. An opening is arranged at the top of the installation chamber. A vibration transmission block is arranged in the opening. The lower end of the vibration transmission block is connected to the output end of the exciter, and the upper end of the vibration transmission block is connected to the rock sample clamping component.

[0021] Optionally, a cover plate is arranged on the upper side of the base. A bearing seat is arranged in the middle of the cover plate. A linear bearing is arranged in the bearing seat, and the vibration transmission block slides through the linear bearing.

[0022] Optionally, the rock sample clamping component includes two reference aluminum sample blocks. The rock sample is used to be arranged between the two reference aluminum sample blocks. The reference aluminum sample blocks are provided with pore fluid channels. The strain test component includes multiple pairs of strain gauges. A part of the strain gauges are arranged on the surface of the rock sample, and another part of the strain gauges are arranged on the surface of the reference aluminum sample blocks.

[0023] Optionally, it further includes a longitudinal wave ultrasonic transducer and a transverse wave ultrasonic transducer, and the longitudinal wave ultrasonic transducer and the transverse wave ultrasonic transducer are symmetrically arranged on both sides of the vertical center line of the rock sample.

[0024] The present invention also provides a rock testing method based on laser calibration and excitation compensation. Using the above-mentioned rock testing device based on laser calibration and excitation compensation, it includes:

[0025] Use a laser vibrometer to measure the acceleration at the output end of the exciter during no-load operation at different operating frequencies.

[0026] Based on the test results of the exciter during no-load operation at different operating frequencies, perform excitation compensation on the exciter through the drive module.

[0027] Use a rock sample clamping component to clamp the rock sample, and set a strain test component on the surface of the rock sample.

[0028] Use the drive module to drive the exciter to operate and test the rock sample.

[0029] Optionally, performing excitation compensation on the exciter through the drive module based on the test results of the exciter during no-load operation at different operating frequencies includes:

[0030] Use the test results of the exciter during no-load operation at different operating frequencies to form relationship data between acceleration and operating frequency.

[0031] Based on the relationship data between acceleration and operating frequency, obtain relationship data between the output amplitude of the drive module and the operating frequency that makes the acceleration at the output end of the exciter consistent at different operating frequencies.

[0032] Transmit the relationship data between the output amplitude of the drive module and the operating frequency to the drive module to compensate the electrical signal output by the drive module, so that the acceleration at the output end of the exciter is consistent at different operating frequencies.

[0033] Optionally, the operating frequency range of the exciter is 2 Hz - 1 MHz.

[0034] The present invention provides a rock testing device and method based on laser calibration and vibration excitation compensation. The beneficial effects are as follows: The rock testing device based on laser calibration and vibration excitation compensation inputs an electrical signal to the vibration exciter through a driving module to drive the vibration exciter to operate. The forced deformation of the rock sample is measured by strain testing components pasted on the axial and radial directions of the sample. Before the test, the acceleration at the output end of the vibration exciter during no-load operation at different operating frequencies is measured by a laser vibrometer. Based on the test results, relationship data between acceleration and operating frequency can be formed. Based on the relationship data between acceleration and operating frequency, vibration excitation compensation can be performed on the vibration exciter. The specific compensation process is to generate relationship data between the output amplitude of the driving module and the operating frequency that enables the acceleration at the output end of the vibration exciter to be consistent at different operating frequencies based on the relationship data between acceleration and operating frequency, and transmit the relationship data between the output amplitude of the driving module and the operating frequency to the driving module to compensate the electrical signal output by the driving module, so that the acceleration at the output end of the vibration exciter is consistent at different operating frequencies; in this way, the mechanical performance of the compensated vibration exciter becomes stable, and the output stress no longer changes with the change of frequency. The compensated strain output changes in a stable form close to a straight line, which is more in line with the actual situation. The rock testing device based on laser calibration and vibration excitation compensation improves the reliability and accuracy of data measurement, and thus can carry out low-frequency rock physics tests more effectively and accurately.

[0035] Other features and advantages of the present invention will be described in detail in the following specific implementation part. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] By describing the exemplary embodiments of the present invention in more detail in conjunction with the drawings, the above and other objects, features, and advantages of the present invention will become more obvious. Among them, in the exemplary embodiments of the present invention, the same reference numerals generally represent the same components.

[0037] Figure 1 FIG. 1 shows a schematic structural diagram of a rock testing device based on laser calibration and vibration excitation compensation according to Embodiment 1 of the present invention.

[0038] Figure 2 FIG. 2 shows a graph of the relationship data between the acceleration at the output end of the vibration exciter during no-load operation and the operating frequency according to Embodiment 1 of the present invention.

[0039] Figure 3 FIG. 3 shows a graph of the relationship data between the output amplitude of the driving module and the operating frequency generated based on the relationship data between acceleration and operating frequency, which can enable the acceleration at the output end of the vibration exciter to be consistent at different operating frequencies according to Embodiment 1 of the present invention.

[0040] Figure 4Shows the relationship data graph of the acceleration and the operating frequency of the exciter running based on laser calibration and vibration excitation compensation according to Embodiment 1 of the present invention.

[0041] Figure 5 Shows the flow chart of a rock testing method based on laser calibration and vibration excitation compensation according to Embodiment 2 of the present invention.

[0042] Explanation of reference numerals:

[0043] 1. Strain testing component; 2. Exciter; 3. Driving module; 4. Laser vibrometer; 5. Base; 6. Top plate; 7. Connecting rod; 8. Vibration transmission block; 9. Cover plate; 10. Linear bearing; 11. Reference aluminum sample block; 12. Pore fluid channel; 13. Longitudinal wave ultrasonic transducer; 14. Transverse wave ultrasonic transducer. Detailed implementation manners

[0044] The preferred embodiments of the present invention will be described in more detail below. Although the preferred embodiments of the present invention are described below, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to make the present invention more thorough and complete, and to fully convey the scope of the present invention to those skilled in the art.

[0045] The present invention provides a rock testing device based on laser calibration and vibration excitation compensation, including:

[0046] A rock sample clamping component for clamping a rock sample;

[0047] A strain testing component for being arranged on the surface of the rock sample;

[0048] An exciter, the output end of which is in contact with the rock sample clamping component;

[0049] A driving module connected to the exciter for inputting an electrical signal to the exciter to drive the exciter to operate;

[0050] A laser vibrometer for testing the acceleration of the output end of the exciter during no-load operation at different operating frequencies.

[0051] Specifically, to solve the problem of poor test accuracy of rock physical tests at different frequencies in a relatively large frequency range in the prior art; such as Figure 1As shown in the figure, the rock testing device based on laser calibration and vibration excitation compensation provided by the present invention inputs an electrical signal to the vibration exciter through a driving module to drive the vibration exciter to operate. The forced deformation of the rock sample is measured by strain testing components pasted on the axial and radial directions of the sample. Before the test, the acceleration at the output end of the vibration exciter during no-load operation at different operating frequencies is measured by a laser vibrometer. Based on the test results, the relationship data between acceleration and operating frequency can be formed. Based on the relationship data between acceleration and operating frequency, vibration excitation compensation can be performed on the vibration exciter. The specific compensation process is to generate the relationship data between the output amplitude of the driving module and the operating frequency that makes the acceleration at the output end of the vibration exciter consistent at different operating frequencies based on the relationship data between acceleration and operating frequency, and transmit the relationship data between the output amplitude of the driving module and the operating frequency to the driving module to compensate the electrical signal output by the driving module, so that the acceleration at the output end of the vibration exciter is consistent at different operating frequencies; in this way, the mechanical performance of the compensated vibration exciter becomes stable, and the output stress no longer changes with the change of frequency. The compensated strain output changes in a stable form close to a straight line, which is more in line with the actual situation. The rock testing device based on laser calibration and vibration excitation compensation improves the reliability and accuracy of data measurement, and thus can carry out low-frequency rock physics tests more effectively and accurately.

[0052] Optionally, the strain testing component is a resistance strain gauge pasted on the axial and radial directions of the rock sample, which can record the forced deformation of the rock sample.

[0053] Optionally, the vibration exciter is a piezoelectric ceramic vibration exciter, which can work under high load compared with the electromagnetic vibrator used in the traditional testing device.

[0054] Optionally, the driving module is a function generator. In other embodiments, a D / A digital-to-analog converter can also be used.

[0055] Optionally, the laser vibrometer is a Doppler laser vibrometer.

[0056] Furthermore, in low-frequency rock physics tests, the vibration exciter converts an electrical signal of a specific frequency into a sinusoidal motion to generate stress. The control of the vibration exciter comes from a sinusoidal stress signal with an accurately corrected amplitude, avoiding the stress amplitude generated by the vibration exciter being too small or too large and affecting the measurement of strain. The present invention adopts appropriate control of the stress gain compensation of the vibration exciter to make the mechanical performance of the vibration exciter stable, and the output stress no longer changes with frequency; the compensated strain output changes in a stable form close to a straight line, which is more in line with the actual situation and improves the accuracy of the test.

[0057] Optionally, a laser vibrometer is used to test the vibration exciter one by one at each frequency point without loading the rock sample to obtain the acceleration at the output end of the vibration exciter in its original state, and obtain a relationship data graph between acceleration and frequency at different frequencies, as Figure 2as shown; then, through the excitation energy correction at each frequency point, the corresponding output amplitude of the drive module is obtained, and this corresponding output amplitude is plotted, as Figure 3 shown, and the energy amplitude is output according to each frequency point, so that the acceleration of the exciter itself forms a horizontal straight line, as Figure 4 shown; in this way, a balanced energy output can be obtained, avoiding the large and small unbalanced jitter of the excitation signal root exciter's response frequency, which affects the test accuracy; in this way, controlling the stress gain compensation of the exciter makes the mechanical performance of the exciter stable, and the output stress no longer changes with the frequency. The compensated strain output changes in a stable form close to a straight line, which is more in line with the actual situation. The calibrated and compensated rock test device improves the reliability and accuracy of data measurement, so that low-frequency rock physics experiments can be carried out more effectively; the above compensation process can be carried out in the way of compensating each frequency point, through manual calculation, to obtain the relationship data graph of the drive module output amplitude and the operating frequency that can make the acceleration at the output end of the exciter consistent at different operating frequencies, and then adjust the drive module according to this data graph, so that the acceleration at the output end of the exciter is consistent at different operating frequencies under the driving action of the drive module.

[0058] Optionally, it further includes a compensation module, and the compensation module includes a data receiving unit, a data processing unit and a data output unit;

[0059] The data receiving unit is used to receive the test results of the exciter when it runs without load at different operating frequencies, and generate the relationship data between acceleration and operating frequency;

[0060] The data processing unit is used to generate the relationship data between the drive module output amplitude and the operating frequency that can make the acceleration at the output end of the exciter consistent at different operating frequencies based on the relationship data between acceleration and operating frequency;

[0061] The data output unit is used to transmit the relationship data between the drive module output amplitude and the operating frequency to the drive module to compensate the electrical signal output by the drive module.

[0062] Specifically, to improve the automatic operation of the rock testing device based on laser calibration and vibration excitation compensation, a compensation module can be set up. The data receiving unit is used to receive the test results of the vibrator during no-load operation at different operating frequencies, and generate the relationship data between acceleration and operating frequency. The relationship data between acceleration and operating frequency is processed for compensation in the data processing unit. The data processing unit generates the relationship data between the output amplitude of the drive module and the operating frequency that makes the acceleration at the output end of the vibrator consistent at different operating frequencies based on the relationship data between acceleration and operating frequency, and transmits the relationship data between the output amplitude of the drive module and the operating frequency to the drive module through the data output unit to achieve compensation for the electrical signal output by the drive module. In this way, the vibration excitation compensation based on laser calibration can be automatically completed, and the degree of automatic operation of the rock testing device based on laser calibration and vibration excitation compensation can be improved.

[0063] Optionally, it further includes a base and a top plate. The base is connected to the top plate through a connecting rod, the vibrator is connected to the base, and the rock sample clamping component is arranged between the vibrator and the top plate.

[0064] Specifically, the base and the top plate are connected through a connecting rod. Threaded parts are provided at both ends of the connecting rod, which penetrate into the base and the top plate and are connected to the base and the top plate. The vibrator is fixedly connected to the base, and the rock sample clamping component is between the top plate and the vibrator, receiving the vibration of the vibrator.

[0065] Optionally, an installation chamber is provided inside the base, the vibrator is installed in the installation chamber, an opening is provided at the top of the installation chamber, a vibration transmission block is arranged in the opening, the lower end of the vibration transmission block is connected to the output end of the vibrator, and the upper end of the vibration transmission block is connected to the rock sample clamping component.

[0066] Specifically, the housing end of the vibrator is fixedly connected inside the installation chamber of the base. The output end of the vibrator is connected to the vibration transmission block that penetrates the opening at the top of the installation chamber. The vibration is transmitted to the rock sample clamping component through the vibration transmission block. The vibrator is arranged in the installation chamber and closely cooperates with the chamber wall of the installation chamber, which can improve its stability during operation.

[0067] Optionally, a cover plate is provided on the upper side of the base. A bearing seat is provided in the middle of the cover plate, and a linear bearing is arranged in the bearing seat. The vibration transmission block slides through the linear bearing.

[0068] Specifically, the cover plate covers the opening at the top of the installation chamber, and the linear bearing is installed through the bearing seat in the middle of it. The vibration transmission block is in sliding fit with the linear bearing, improving the accuracy of vibration transmission.

[0069] Optionally, the rock sample clamping component includes two reference aluminum sample blocks, the rock sample is configured to be disposed between the two reference aluminum sample blocks, the reference aluminum sample blocks are provided with pore fluid channels, the strain testing component includes multiple pairs of strain gauges, a part of the strain gauges are disposed on the surface of the rock sample, and another part of the strain gauges are disposed on the surface of the reference aluminum sample blocks.

[0070] Specifically, two reference aluminum sample blocks, one on top and one at the bottom, serve as the rock sample clamping component to clamp the rock sample. Pore fluid channels are provided inside the two reference aluminum sample blocks for injecting fluid to enable relevant rock sample testing projects. Six pairs of strain gauges can be provided. Among them, four pairs of semiconductor type strain gauges with insulating substrates are attached to the surface of the rock sample. Two pairs out of the four pairs are arranged vertically, and the other two pairs out of the four pairs are arranged horizontally. The remaining two pairs of semiconductor type strain gauges are attached to the surface of the reference aluminum sample blocks and are arranged vertically.

[0071] Furthermore, the outer side of the rock sample is wrapped with an epoxy resin layer instead of the traditional Kapton glue, which can obtain reliable and reproducible experimental data while improving the adhesion of the strain gauges. In one embodiment, the measurement frequency range of the rock testing device based on laser calibration and vibration excitation compensation is 2 Hz - 1 MHz. It can measure the longitudinal wave and transverse wave velocities and the elastic parameters of the rock sample, and can adapt to high temperature and high pressure conditions, that is, it can simulate the high temperature and high pressure reservoir conditions in deep layers. The pore fluid channel allows independent control of pore fluid and fluid exchange independent of the confining pressure.

[0072] Optionally, it further includes a longitudinal wave ultrasonic transducer and a transverse wave ultrasonic transducer, and the longitudinal wave ultrasonic transducer and the transverse wave ultrasonic transducer are symmetrically arranged on both sides of the vertical center line of the rock sample.

[0073] Specifically, the longitudinal wave ultrasonic transducer and the transverse wave ultrasonic transducer are placed on the left and right sides of the vertical central axis of the rock sample to obtain ultrasonic data at the same position.

[0074] In summary, the test principle of the rock testing device based on laser calibration and vibration excitation compensation provided by the present invention is as follows: Based on the application of the electrical measurement method in rock physical experiments, the electrical measurement method can be used to test the strain of a specified area on the surface of an object. The measurement method is to convert the measured strain change into a resistance change through certain strain sensing components, that is, the strain gauges in the present invention, and then convert it into a voltage (or current) change through relevant instruments and amplify it with an amplifier, and finally give the display and processing results. The sensing component is the sensitive resistance strain gauge. The resistance strain gauge is a resistive sensor and is the key component of the electrical measurement method. It reflects the strain of the measured sample by the change of its own resistance value. The strain generated by mechanical vibration sensed by the pasted strain gauge maintains a proportional relationship with the resistance value change rate, and the proportional coefficient is the strain gauge sensitivity coefficient, which is determined by the resistance strain gauge itself. The relevant instrument is the resistance strain gauge based on the Wheatstone bridge. The characteristic of the Wheatstone bridge is that the resistance change rate and the output voltage value maintain a high linear relationship; in one embodiment, 4 pairs of semiconductor type strain gauges with insulating substrates are pasted on the surface of the rock sample, 2 pairs are arranged vertically and 2 pairs are arranged horizontally, and 2 pairs of semiconductor type strain gauges arranged vertically are pasted on the surface of the reference aluminum sample. When the exciter emits a sine signal to vibrate, the rock sample and the reference aluminum sample block will both deform to varying degrees. The resistance of the semiconductor type strain gauges in the vertical and horizontal directions pasted on the surface of the rock sample and the semiconductor type strain gauges in the vertical direction pasted on the surface of the reference aluminum sample will change with the sine signal, and the relative change value of the resistance value will be converted into a voltage signal through the Wheatstone bridge circuit, and finally the strain information can be obtained through amplification and acquisition processing.

[0075] The exciter, that is, the vibrator, is one of the core hardware components in the rock testing device based on laser calibration and vibration excitation compensation. The vibration source in the rock testing device based on laser calibration and vibration excitation compensation uses an electrodynamic exciter. Its working principle is that a current-carrying conductor moves under the action of a magnetic force in a magnetic field. It is very suitable as a power generator in mechanical impedance measurement because it only requires a small force. It can also be used to calibrate vibration sensors. It has high sensitivity and a wide range of frequency responses, up to 18 kHz; its suspension system consists of radial bending springs that limit the movement of components and can generate nearly perfect linear motion. The laminated bending springs provide a high degree of damping to reduce distortion caused by bending resonance; the maximum displacement allowed by the exciter is 6 mm, and the maximum force is 10 N. Figure 2 The figure shows the relationship data graph of acceleration and frequency at different frequencies with the same amplitude output.

[0076] The present invention also provides a rock testing method based on laser calibration and vibration excitation compensation, which uses the above-mentioned rock testing device based on laser calibration and vibration excitation compensation, including:

[0077] Use a laser vibrometer to measure the acceleration at the output end of the exciter during no-load operation at different operating frequencies;

[0078] Based on the test results of the exciter during no-load operation at different operating frequencies, perform excitation compensation on the exciter through the drive module;

[0079] Use a rock sample clamping component to clamp the rock sample, and set a strain test component on the surface of the rock sample;

[0080] Use the drive module to drive the exciter to operate and test the rock sample.

[0081] Specifically, for the rock testing method based on laser calibration compensation provided by the present invention, using the above-mentioned rock testing device based on laser calibration compensation, before testing, compensation is performed in the way of laser calibration excitation compensation. Use a laser vibrometer to measure the acceleration at the output end of the exciter during no-load operation at different operating frequencies. Adopt the method of testing each frequency point, and record the test results to generate a relationship data graph of acceleration and operating frequency as shown in Figure 2 Then, adopt the method of compensating each frequency point, generate the relationship data of the output amplitude of the drive module and the operating frequency that makes the acceleration at the output end of the exciter consistent at different operating frequencies based on the relationship data of acceleration and operating frequency, and record the compensation results to generate a relationship data graph of the output amplitude of the drive module and the operating frequency as shown in Figure 3 Use the relationship data of the output amplitude of the drive module and the operating frequency to compensate the drive module, perform excitation compensation on the exciter through the drive module, so that the acceleration at the output end of the exciter is consistent at different operating frequencies; then clamp the rock sample well with the rock sample clamping component, attach the strain test component on the surface of the rock sample, start the drive module to drive the exciter to operate, and then perform the physical low-frequency test of the rock sample; such prior excitation compensation can avoid large and small unbalanced jitters between the excitation signal and the response frequency of the exciter, thereby improving the test accuracy.

[0082] Optionally, performing excitation compensation on the exciter through the drive module based on the test results of the exciter during no-load operation at different operating frequencies includes:

[0083] Use the test results of the exciter during no-load operation at different operating frequencies to form the relationship data of acceleration and operating frequency;

[0084] Based on the relationship data of acceleration and operating frequency, obtain the relationship data of the output amplitude of the drive module and the operating frequency that makes the acceleration at the output end of the exciter consistent at different operating frequencies;

[0085] Transmit the relationship data between the output amplitude and the operating frequency of the drive module to the drive module to compensate the electrical signal output by the drive module, so that the acceleration at the output end of the exciter is consistent at different operating frequencies.

[0086] Specifically, the present invention uses a Doppler laser vibrometer to test the exciter at each frequency point without loading the rock sample, obtains the acceleration at the output end of the exciter in its original state, obtains the relationship graph between the acceleration and the frequency at different frequencies, and then through the excitation energy correction at each frequency point, obtains the corresponding output amplitude of the function generator, plots this corresponding output amplitude, and outputs according to the energy amplitude at each frequency point, so that the acceleration output of the exciter itself forms a horizontal straight line, so that a balanced energy output can be obtained, avoiding the large and small unbalanced jitter between the excitation signal and the response frequency of the exciter, thus affecting the test accuracy. Such control of the stress gain compensation of the exciter makes the mechanical performance of the exciter stable, and the output stress no longer changes with the frequency; the compensated strain output changes in a stable form close to a straight line, which is more in line with the actual situation; after calibration and compensation, the reliability and accuracy of data measurement are improved, so that low-frequency rock physics tests can be carried out more effectively.

[0087] Optionally, the operating frequency range of the exciter is 2 Hz - 1 MHz.

[0088] Specifically, through the above-mentioned rock testing method based on laser calibration and excitation compensation, excitation compensation is performed on the above-mentioned rock testing device based on laser calibration and excitation compensation. The compensated rock testing device based on laser calibration and excitation compensation can quantitatively study the elastic parameter dispersion characteristics of fluid-containing rocks in a wide frequency band range, laying an important foundation for establishing the quantitative relationship between reservoir elastic parameters and seismic responses and developing new technologies for reservoir prediction and fluid identification.

[0089] Embodiment 1

[0090] As Figure 1 shown, the present invention provides a rock testing device based on laser calibration and excitation compensation, including:

[0091] A rock sample clamping component for clamping a rock sample;

[0092] A strain testing component 1 for being arranged on the surface of the rock sample;

[0093] An exciter 2, the output end of the exciter 2 is in contact with the rock sample clamping component;

[0094] A drive module 3, the drive module 3 is connected to the exciter 2 and is used to input an electrical signal to the exciter 2 to drive the exciter 2 to operate;

[0095] The laser vibrometer 4 is used to measure the acceleration of the output end of the shaker 2 when it operates without load at different operating frequencies.

[0096] Specifically, to solve the problem of poor test accuracy for rock physical tests at different frequencies within a large frequency range in the prior art; the rock test device based on laser calibration and vibration excitation compensation provided by the present invention drives the shaker 2 to operate by inputting an electrical signal to the shaker 2 through the drive module 3, measures the forced deformation of the rock sample through the strain test components 1 pasted on the axial and radial directions of the sample. Before the test, the laser vibrometer 4 measures the acceleration of the output end of the shaker 2 when it operates without load at different operating frequencies. Based on this test result, relationship data between acceleration and operating frequency can be formed. Based on this relationship data between acceleration and operating frequency, vibration excitation compensation can be performed on the shaker 2. The specific compensation process is to generate relationship data between the output amplitude of the drive module 3 and the operating frequency that makes the acceleration of the output end of the shaker 2 consistent at different operating frequencies based on the relationship data between acceleration and operating frequency, and transmit the relationship data between the output amplitude of the drive module 3 and the operating frequency to the drive module 3 to compensate the electrical signal output by the drive module 3, so that the acceleration of the output end of the shaker 2 is consistent at different operating frequencies; in this way, the mechanical performance of the compensated shaker 2 becomes stable, the output stress no longer changes with the change of frequency, the compensated strain output changes in a stable form close to a straight line, which is more in line with the actual situation. The rock test device based on laser calibration and vibration excitation compensation improves the reliability and accuracy of data measurement, and thus can carry out low-frequency rock physical tests more effectively and accurately.

[0097] In this embodiment, the strain test components 1 are resistance strain gauges pasted on the axial and radial directions of the rock sample, which can record the forced deformation of the rock sample.

[0098] In this embodiment, the shaker 2 is a piezoelectric ceramic shaker 2, which can work under high load compared with the electromagnetic vibrator used in the traditional test device.

[0099] In this embodiment, the drive module 3 is a function generator. In other embodiments, a D / A digital-to-analog converter can also be used.

[0100] In this embodiment, the laser vibrometer 4 is a Doppler laser vibrometer 4.

[0101] Further, in the low-frequency rock physics test, the exciter 2 converts an electrical signal of a specific frequency into a sinusoidal motion to generate stress. The control of the exciter 2 comes from a sinusoidal stress signal with precisely calibrated amplitude, avoiding the stress amplitude generated by the exciter 2 being too small or too large and affecting the strain measurement. The present invention adopts appropriate control of the stress gain compensation of the exciter 2 to make the mechanical performance of the exciter 2 stable, and the output stress no longer changes with frequency; the compensated strain output changes in a stable form close to a straight line, which is more in line with the actual situation and improves the accuracy of the test.

[0102] Optionally, a laser vibrometer 4 is used to test each frequency point of the exciter 2 itself without loading a rock sample, obtain the acceleration at the output end of the exciter 2 in its original state, and obtain a relationship data graph of acceleration and frequency at different frequencies, as Figure 2 shown; then through the excitation energy correction of each frequency point, the corresponding output amplitude of the drive module 3 is obtained, and this corresponding output amplitude is plotted, as Figure 3 shown, and output according to the energy amplitude of each frequency point, so that the acceleration of the exciter 2 itself forms a horizontal straight line, as Figure 4 shown; in this way, a balanced energy output can be obtained, avoiding the large and small unbalanced jitter of the excitation signal root excitation frequency of the exciter 2 and affecting the test accuracy; in this way, controlling the stress gain compensation of the exciter 2 makes the mechanical performance of the exciter 2 stable, the output stress no longer changes with frequency, and the compensated strain output changes in a stable form close to a straight line, which is more in line with the actual situation. The calibrated and compensated rock test device improves the reliability and accuracy of data measurement, so that low-frequency rock physics experiments can be carried out more effectively; the above compensation process can be carried out in the way of compensating each frequency point, through manual calculation, to obtain a relationship data graph of the output amplitude of the drive module 3 and the operating frequency that can make the acceleration at the output end of the exciter 2 consistent at different operating frequencies, and then adjust the drive module 3 according to this data graph, so that the acceleration at the output end of the exciter 2 is consistent at different operating frequencies under the driving action of the drive module 3.

[0103] In this embodiment, a compensation module is further included. The compensation module includes a data receiving unit, a data processing unit, and a data output unit;

[0104] The data receiving unit is used to receive the test results of the exciter 2 during no-load operation at different operating frequencies and generate relationship data of acceleration and operating frequency;

[0105] The data processing unit is used to generate relationship data of the output amplitude of the drive module 3 and the operating frequency that can make the acceleration at the output end of the exciter 2 consistent at different operating frequencies based on the relationship data of acceleration and operating frequency;

[0106] The data output unit is used to transmit the relationship data between the output amplitude and the operating frequency of the drive module 3 to the drive module 3 to compensate for the electrical signal output by the drive module 3.

[0107] Specifically, to improve the automatic operation of the rock testing device based on laser calibration and vibration excitation compensation, a compensation module is set in this embodiment. The data receiving unit is used to receive the test results of the exciter 2 during no-load operation at different operating frequencies and generate the relationship data between acceleration and operating frequency. The relationship data between acceleration and operating frequency is processed for compensation in the data processing unit. The data processing unit generates the relationship data between the output amplitude and the operating frequency of the drive module 3 that makes the acceleration at the output end of the exciter 2 consistent at different operating frequencies based on the relationship data between acceleration and operating frequency, and the data output unit conveys the relationship data between the output amplitude and the operating frequency of the drive module 3 to the drive module 3 to achieve compensation for the electrical signal output by the drive module 3; in this way, the vibration excitation compensation based on laser calibration can be automatically completed, and the degree of automatic operation of the rock testing device based on laser calibration and vibration excitation compensation can be improved.

[0108] In this embodiment, it further includes a base 5 and a top plate 6. The base 5 is connected to the top plate 6 through a connecting rod 7. The exciter 2 is connected to the base 5, and the rock sample clamping component is arranged between the exciter 2 and the top plate 6.

[0109] Specifically, the base 5 and the top plate 6 are connected through the connecting rod 7. Threaded parts are arranged at both ends of the connecting rod 7, which penetrate into the base 5 and the top plate 6 and are connected to the base 5 and the top plate 6. The exciter 2 is fixedly connected to the base 5, and the rock sample clamping component is between the top plate 6 and the exciter 2 and receives the vibration of the exciter 2.

[0110] In this embodiment, an installation chamber is arranged inside the base 5. The exciter 2 is installed in the installation chamber. An opening is arranged at the top of the installation chamber, and a vibration transmission block 8 is arranged in the opening. The lower end of the vibration transmission block 8 is connected to the output end of the exciter 2, and the upper end of the vibration transmission block 8 is connected to the rock sample clamping component.

[0111] In this embodiment, the housing end of the exciter 2 is fixedly connected inside the installation chamber of the base 5. The output end of the exciter 2 is connected to the vibration transmission block 8 that penetrates the opening at the top of the installation chamber. The vibration is transmitted to the rock sample clamping component through the vibration transmission block 8. The exciter 2 is arranged in the installation chamber and is in close fit with the chamber wall of the installation chamber, which can improve its stability during operation.

[0112] In this embodiment, a cover plate 9 is arranged on the upper side of the base 5. A bearing seat is arranged in the middle of the cover plate 9, and a linear bearing 10 is arranged inside the bearing seat. The vibration transmission block 8 slides through the linear bearing 10.

[0113] Specifically, the cover plate 9 covers the opening at the top of the installation chamber, and a linear bearing 10 is installed through the bearing seat in the middle of the device. The vibration transmission block 8 is slidably matched with the linear bearing 10 to improve the accuracy of vibration transmission.

[0114] In this embodiment, the rock sample clamping component includes two reference aluminum sample blocks 11. The rock sample is arranged between the two reference aluminum sample blocks 11. The reference aluminum sample blocks 11 are provided with pore fluid channels 12. The strain test component 1 includes multiple pairs of strain gauges. Part of the strain gauges are arranged on the surface of the rock sample, and the other part of the strain gauges are arranged on the surface of the reference aluminum sample blocks 11.

[0115] Specifically, the upper and lower two reference aluminum sample blocks 11 are used as the rock sample clamping component to clamp the rock sample. The two reference aluminum sample blocks 11 are internally provided with pore fluid channels 12 for injecting fluid to realize relevant rock sample test items. Six pairs of strain gauges can be set. Among them, four pairs of semiconductor type strain gauges with insulating substrates are attached to the surface of the rock sample. Two pairs of the four pairs are arranged vertically, and the other two pairs of the four pairs are arranged horizontally. The remaining two pairs of semiconductor type strain gauges are attached to the surface of the reference aluminum sample blocks 11 and arranged vertically.

[0116] Furthermore, the outer side of the rock sample is wrapped with an epoxy resin layer instead of the traditional Kapton glue, which can obtain reliable and repeatable experimental data while improving the adhesion of the strain gauges. In this embodiment, the measurement frequency range of the rock testing device based on laser calibration and vibration excitation compensation is 2 Hz - 1 MHz. It can measure the longitudinal wave and transverse wave velocities and the elastic parameters of the rock sample, and can adapt to high temperature and high pressure conditions, that is, it can simulate the conditions of deep high temperature and high pressure reservoirs. The pore fluid channel 12 allows pore fluid control and fluid exchange independent of the confining pressure.

[0117] In this embodiment, it further includes a longitudinal wave ultrasonic transducer 13 and a transverse wave ultrasonic transducer 14. The longitudinal wave ultrasonic transducer 13 and the transverse wave ultrasonic transducer 14 are symmetrically arranged on both sides of the vertical center line of the rock sample.

[0118] Specifically, the longitudinal wave ultrasonic transducer 13 and the transverse wave ultrasonic transducer 14 are placed on the left and right sides of the vertical central axis of the rock sample to obtain ultrasonic data at the same position.

[0119] In summary, the test principle of the rock testing device based on laser calibration and vibration excitation compensation provided by the present invention is as follows: Based on the application of the electrical measurement method in rock physical experiments, the electrical measurement method can be used to test the strain in a specified area on the surface of an object. The measurement method is to convert the measured strain change into a resistance change through certain strain sensing components, that is, the strain gauges in the present invention, and then convert it into a voltage (or current) change through relevant instruments and amplify it with an amplifier, and finally give the display and processing results. The sensing component is the sensitive resistance strain gauge. The resistance strain gauge is a resistive sensor and is the key component of the electrical measurement method. It reflects the strain of the measured sample by the change in its own resistance value. The strain generated by mechanical vibration sensed by the pasted strain gauge maintains a proportional relationship with the resistance value change rate, and the proportional coefficient is the strain gauge sensitivity coefficient, which is determined by the resistance strain gauge itself. The relevant instrument is the resistance strain gauge based on the Wheatstone bridge. The characteristic of the Wheatstone bridge is that the resistance change rate and the output voltage value maintain a high linear relationship; in this embodiment, 4 pairs of semiconductor type strain gauges with insulating substrates are pasted on the surface of the rock sample, with 2 pairs arranged vertically and 2 pairs arranged horizontally, and 2 pairs of semiconductor type strain gauges arranged vertically are pasted on the surface of the reference aluminum sample. When the exciter 2 emits a sine signal to vibrate, both the rock sample and the reference aluminum sample block 11 will undergo varying degrees of deformation. The resistance of the semiconductor type strain gauges in the vertical and horizontal directions on the surface of the rock sample and the semiconductor type strain gauges in the vertical direction on the surface of the reference aluminum sample will change with the sine signal, and the relative change value of the resistance value will be converted into a voltage signal through the Wheatstone bridge circuit, and finally, the strain information can be obtained through amplification and acquisition processing.

[0120] The exciter 2, that is, the vibrator, is one of the core hardware components in the rock testing device based on laser calibration and vibration excitation compensation. The vibration source in the rock testing device based on laser calibration and vibration excitation compensation uses an electrodynamic exciter 2. Its working principle is that a current-carrying conductor moves under the action of a magnetic field force in a magnetic field. It is very suitable as a power generator in mechanical impedance measurement because it only requires a small force. It can also be used to calibrate vibration sensors. It has high sensitivity and a wide range of frequency responses, up to 18 kHz; its suspension system consists of radial bending springs that limit the movement of the components and can generate nearly perfect linear motion. The laminated bending springs provide a high degree of damping to reduce distortion caused by bending resonance; the maximum displacement allowed by the exciter 2 is 6 mm, and the maximum force is 10 N. Figure 2 The figure shows the relationship data graph of acceleration and frequency at different frequencies with the same amplitude output.

[0121] Embodiment 2

[0122] As Figure 5As shown in the figure, the present invention also provides a rock testing method based on laser calibration and vibration excitation compensation, which uses the above-mentioned rock testing device based on laser calibration and vibration excitation compensation, and includes:

[0123] Using a laser vibrometer 4 to measure the acceleration at the output end of the exciter 2 when it runs without load at different operating frequencies;

[0124] Based on the test results of the exciter 2 when it runs without load at different operating frequencies, the exciter 2 is compensated for vibration excitation through the drive module 3;

[0125] Using a rock sample clamping component to clamp the rock sample, and arranging a strain testing component 1 on the surface of the rock sample;

[0126] Using the drive module 3 to drive the exciter 2 to run and test the rock sample.

[0127] Specifically, for the rock testing method based on laser calibration and compensation provided by the present invention, using the above-mentioned rock testing device based on laser calibration and compensation, before the test, compensation is carried out in the way of laser calibration and vibration excitation compensation. Using a laser vibrometer 4 to measure the acceleration at the output end of the exciter 2 when it runs without load at different operating frequencies, and adopting the method of testing each frequency point, and recording the test results, generating a relationship data graph of acceleration and operating frequency as shown in Figure 2 the figure, and then adopting the method of compensating each frequency point, generating the relationship data of the output amplitude of the drive module 3 and the operating frequency that makes the acceleration at the output end of the exciter 2 consistent at different operating frequencies based on the relationship data of acceleration and operating frequency, and recording the compensation results, generating a relationship data graph of the output amplitude of the drive module 3 and the operating frequency as shown in Figure 3 the figure, using the relationship data of the output amplitude of the drive module 3 and the operating frequency to compensate the drive module 3, and compensating the exciter 2 for vibration excitation through the drive module 3, so that the acceleration at the output end of the exciter 2 is consistent at different operating frequencies; then clamping the rock sample well with the rock sample clamping component, pasting the strain testing component 1 on the surface of the rock sample, starting the drive module 3 to drive the exciter 2 to run, and then carrying out the physical low-frequency test of the rock sample; such prior vibration excitation compensation can avoid the large and small unbalanced jitter between the excitation signal and the response frequency of the exciter 2, thereby improving the test accuracy.

[0128] In this embodiment, compensating the exciter 2 for vibration excitation through the drive module 3 based on the test results of the exciter 2 when it runs without load at different operating frequencies includes:

[0129] Using the test results of the exciter 2 when it runs without load at different operating frequencies to form the relationship data of acceleration and operating frequency;

[0130] Based on the relationship data between acceleration and operating frequency, obtain the relationship data between the output amplitude of the drive module 3 and the operating frequency that enables the acceleration at the output end of the exciter 2 to be consistent at different operating frequencies;

[0131] Transmit the relationship data between the output amplitude of the drive module 3 and the operating frequency to the drive module 3 to compensate for the electrical signal output by the drive module 3, so that the acceleration at the output end of the exciter 2 is consistent at different operating frequencies.

[0132] Specifically, the present invention uses a Doppler laser vibrometer 4 to test the exciter 2 at each frequency point without loading a rock sample, obtain the acceleration at the output end of the original state of the exciter 2, and obtain the relationship graph between acceleration and frequency at different frequencies. Then, through the excitation energy correction at each frequency point, obtain the corresponding output amplitude of the function generator, plot this corresponding output amplitude, and output according to the energy amplitude at each frequency point, so that the acceleration output of the exciter 2 itself forms a horizontal straight line. In this way, a balanced energy output can be obtained, avoiding the large and small unbalanced jitter between the excitation signal and the response frequency of the exciter 2, thereby affecting the test accuracy. Such control of the stress gain compensation of the exciter 2 makes the mechanical properties of the exciter 2 stable, and the output stress no longer changes with frequency; the compensated strain output changes in a stable form close to a straight line, which is more in line with the actual situation; after calibration and compensation, the reliability and accuracy of data measurement are improved, so that low-frequency rock physics tests can be carried out more effectively.

[0133] In this embodiment, the operating frequency range of the exciter 2 is 2 Hz - 1 MHz.

[0134] Specifically, through the above-mentioned rock testing method based on laser calibration and excitation compensation, excitation compensation is performed on the above-mentioned rock testing device based on laser calibration and excitation compensation. The compensated rock testing device based on laser calibration and excitation compensation can quantitatively study the elastic parameter dispersion characteristics of fluid-containing rocks in a wide frequency band range, laying an important foundation for establishing the quantitative relationship between reservoir elastic parameters and seismic responses and developing new technologies for reservoir prediction and fluid identification.

[0135] The various embodiments of the present invention have been described above. The above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations are obvious to those of ordinary skill in the art in the technical field without departing from the scope and spirit of the described embodiments.

Claims

1. A rock testing device based on laser calibration and vibration excitation compensation, characterized in that, it includes: A rock sample clamping component for clamping a rock sample; A strain testing component for being arranged on the surface of the rock sample; A vibrator, the output end of which is in contact with the rock sample clamping component; A driving module connected to the vibrator for inputting an electrical signal to the vibrator to drive the vibrator to operate; A laser vibrometer for testing the acceleration of the output end of the vibrator during no-load operation at different operating frequencies.

2. The rock testing device based on laser calibration and vibration excitation compensation according to claim 1, characterized in that, it further includes a compensation module, and the compensation module includes a data receiving unit, a data processing unit and a data output unit; The data receiving unit is used for receiving the test results of the vibrator during no-load operation at different operating frequencies and generating relationship data between acceleration and operating frequency; The data processing unit is used for generating relationship data between the output amplitude of the driving module and the operating frequency that enables the acceleration of the output end of the vibrator to be consistent at different operating frequencies based on the relationship data between acceleration and operating frequency; The data output unit is used for transmitting the relationship data between the output amplitude of the driving module and the operating frequency to the driving module to compensate the electrical signal output by the driving module.

3. The rock testing device based on laser calibration and vibration excitation compensation according to claim 1, characterized in that, it further includes a base and a top plate, the base is connected to the top plate through a connecting rod, the vibrator is connected to the base, and the rock sample clamping component is arranged between the vibrator and the top plate.

4. The rock testing device based on laser calibration and vibration excitation compensation according to claim 3, characterized in that, an installation chamber is arranged inside the base, the vibrator is installed in the installation chamber, an opening is arranged at the top of the installation chamber, a vibration transmission block is arranged in the opening, the lower end of the vibration transmission block is connected to the output end of the vibrator, and the upper end of the vibration transmission block is connected to the rock sample clamping component.

5. The rock testing device based on laser calibration and vibration excitation compensation according to claim 4, characterized in that, a cover plate is arranged on the upper side of the base, a bearing seat is arranged in the middle of the cover plate, a linear bearing is arranged in the bearing seat, and the vibration transmission block slides through the linear bearing.

6. The rock testing device based on laser calibration and vibration excitation compensation according to claim 1, characterized in that, the rock sample clamping component includes two reference aluminum sample blocks, the rock sample is arranged between the two reference aluminum sample blocks, the reference aluminum sample blocks are provided with pore fluid channels, the strain testing component includes multiple pairs of strain gauges, a part of the strain gauges are arranged on the surface of the rock sample, and another part of the strain gauges are arranged on the surface of the reference aluminum sample blocks.

7. The rock testing device based on laser calibration and vibration excitation compensation according to claim 6, characterized in that, It further includes a longitudinal wave ultrasonic transducer and a transverse wave ultrasonic transducer, and the longitudinal wave ultrasonic transducer and the transverse wave ultrasonic transducer are symmetrically arranged on both sides of the vertical center line of the rock sample.

8. A rock testing method based on laser calibration and vibration excitation compensation, using the rock testing device based on laser calibration and vibration excitation compensation according to any one of claims 1-7, Characterized in that, It includes: Using a laser vibrometer to measure the acceleration of the output end of the vibration exciter when it runs without load at different operating frequencies; Based on the test results of the vibration exciter when it runs without load at different operating frequencies, performing vibration excitation compensation on the vibration exciter through the drive module; Using the rock sample clamping component to clamp the rock sample, and arranging a strain testing component on the surface of the rock sample; Using the drive module to drive the vibration exciter to run and test the rock sample.

9. The rock testing method based on laser calibration and vibration excitation compensation according to claim 8, Characterized in that, Performing vibration excitation compensation on the vibration exciter through the drive module based on the test results of the vibration exciter when it runs without load at different operating frequencies includes: Using the test results of the vibration exciter when it runs without load at different operating frequencies to form relationship data between acceleration and operating frequency; Based on the relationship data between acceleration and operating frequency, obtaining relationship data between the output amplitude of the drive module and the operating frequency that makes the acceleration of the output end of the vibration exciter consistent at different operating frequencies; Transmitting the relationship data between the output amplitude of the drive module and the operating frequency to the drive module to compensate the electrical signal output by the drive module, so that the acceleration of the output end of the vibration exciter is consistent at different operating frequencies.

10. The rock testing method based on laser calibration and vibration excitation compensation according to claim 8, Characterized in that, The operating frequency range of the vibration exciter is 2 Hz - 1 MHz.

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