Rock property detection and waveform prediction method and system based on ultrasonic transmission method

Abstract

The present disclosure provides a method and system for detecting rock characteristics and predicting waveforms based on the ultrasonic transmission method. Among them, the method includes: a control signal excitation unit exciting an ultrasonic transmitting device to transmit a first ultrasonic signal based on set transmission parameters for testing a first propagation distance; receiving, by an ultrasonic receiving device, the first ultrasonic signal that has passed through the rock sample to be tested, with the ultrasonic transmitting device and the ultrasonic receiving device located on both sides of the rock sample to be tested; collecting the first ultrasonic signal received by the ultrasonic receiving device and preprocessing the collected first ultrasonic signal; determining, based on the preprocessed first ultrasonic signal, the characteristic information of the rock sample to be tested at the first propagation distance; and predicting, based on the characteristic information and a preset waveform prediction model, the ultrasonic waveform of the rock sample to be tested at a second propagation distance. The present disclosure can accurately detect rock characteristics and predict ultrasonic waveforms.

Description

Technical Field

[0001] The present disclosure relates to the technical field of rock property detection, and particularly to a method and system for rock property detection and waveform prediction based on the ultrasonic transmission method. Background Art

[0002] In exploration seismology, accurately measuring the elastic parameters of underground media (such as rock properties) is crucial for resource exploration (such as the exploration of aquifers, solid and petroleum deposits). However, there is currently a lack of effective means for accurately detecting rock properties and predicting ultrasonic waveforms. Summary of the Invention

[0003] Embodiments of the present disclosure provide a method and system for rock property detection and waveform prediction based on the ultrasonic transmission method.

[0004] According to a first aspect of the embodiments of the present disclosure, there is provided a method for rock property detection and waveform prediction based on the ultrasonic transmission method, including:

[0005] A control signal excitation unit excites an ultrasonic transmitting device to transmit a first ultrasonic signal based on set transmission parameters for testing a first propagation distance;

[0006] The ultrasonic receiving device receives the first ultrasonic signal transmitted through the rock sample to be tested, and the ultrasonic transmitting device and the ultrasonic receiving device are located on both sides of the rock sample to be tested;

[0007] Collect the first ultrasonic signal received by the ultrasonic receiving device, and preprocess the collected first ultrasonic signal;

[0008] According to the preprocessed first ultrasonic signal, determine the characteristic information of the rock sample to be tested at the first propagation distance, where the characteristic information includes at least one of the propagation speed, attenuation coefficient, and velocity dispersion of ultrasonic waves in the rock sample to be tested;

[0009] Based on the characteristic information and a preset waveform prediction model, predict the ultrasonic waveform of the rock sample to be tested at a second propagation distance.

[0010] According to a second aspect of the embodiments of the present disclosure, there is provided a system for rock property detection and waveform prediction based on the ultrasonic transmission method, including:

[0011] An ultrasonic transmitting device for transmitting a first ultrasonic signal based on set transmission parameters for testing a first propagation distance;

[0012] An ultrasonic receiving device for receiving the first ultrasonic signal transmitted through the rock sample to be tested, and the ultrasonic transmitting device and the ultrasonic receiving device are located on both sides of the rock sample to be tested;

[0013] A data acquisition and processing unit, configured to acquire a first ultrasonic signal received by the ultrasonic receiving device, preprocess the acquired first ultrasonic signal, and determine characteristic information of the rock sample to be measured at the first propagation distance according to the preprocessed first ultrasonic signal, where the characteristic information includes at least one of the propagation speed, attenuation coefficient, and velocity dispersion of ultrasonic waves in the rock sample to be measured;

[0014] A waveform prediction unit, configured to predict the ultrasonic waveform of the rock sample to be measured at the second propagation distance based on the characteristic information and a preset waveform prediction model.

[0015] According to the technical solution of the present disclosure, the characteristic information of the rock can be measured more accurately, the measurement error can be reduced, and thus the detection accuracy can be improved. The present disclosure can also more accurately predict the ultrasonic waveforms of different types of rocks (especially sandstone, etc.) at different propagation distances, providing a strong basis for in-depth understanding of the internal structure and characteristics of the rocks. Optionally, the solution involved in the present disclosure can be applied to multiple fields such as geological exploration, mine exploitation, and petroleum engineering, which helps to improve the efficiency of resource exploration, evaluate the rock stability, etc., and has important economic and engineering values.

[0016] Some of the additional aspects and advantages of the present disclosure will be given in the following description, some will become obvious from the following description, or will be understood through the practice of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and / or additional aspects and advantages of the present disclosure will become obvious and easy to understand from the following description of the embodiments in conjunction with the drawings, where:

[0018] Figure 1 is a block diagram of a rock characteristic detection and waveform prediction system based on the ultrasonic transmission method provided by an embodiment of the present disclosure;

[0019] Figure 2 is a schematic flowchart of a rock characteristic detection and waveform prediction method based on the ultrasonic transmission method provided by an embodiment of the present disclosure;

[0020] Figure 3 is a schematic diagram of an experimental system provided by an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0021] The embodiments of the present disclosure will be described in detail below. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary and are intended to explain the present disclosure, and should not be construed as a limitation to the present disclosure.

[0022] The exemplary embodiments of the present disclosure will be described below in conjunction with the accompanying drawings. Various details of the embodiments of the present disclosure are included to facilitate understanding, and they should be considered merely exemplary. Therefore, those of ordinary skill in the art should recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present disclosure. Similarly, descriptions of well-known functions and structures are omitted in the following description for clarity and conciseness.

[0023] The terms used in one or more embodiments of the present disclosure are for the purpose of describing specific embodiments only and are not intended to limit one or more embodiments of the present disclosure. It should also be understood that the term "and / or" used in one or more embodiments of the present disclosure refers to and includes any or all possible combinations of one or more associated listed items.

[0024] In the embodiments of the present disclosure, "a plurality" means two or more. In some embodiments, notations such as "at least one of A and B", "A and / or B", "in one case A, in another case B", "in response to one case A, in response to another case B", etc. may include the following technical solutions according to the situation: in some embodiments A (executing A independently of B); in some embodiments B (executing B independently of A); in some embodiments selecting to execute from A and B (A and B are selectively executed); in some embodiments A and B (both A and B are executed). The same is true when there are more branches such as A, B, C, etc.

[0025] The method and system for detecting rock properties and predicting waveforms based on the ultrasonic transmission method according to the embodiments of the present disclosure will be described below with reference to the accompanying drawings.

[0026] It should be noted that the execution subject of the method for detecting rock properties and predicting waveforms based on the ultrasonic transmission method according to the embodiments of the present disclosure can be a system for detecting rock properties and predicting waveforms based on the ultrasonic transmission method. This system can be implemented in a software and / or hardware manner and can be configured in an electronic device. Exemplarily, the electronic device may include, but is not limited to, a terminal, a server, etc.

[0027] Figure 1 It is a block diagram of the system for detecting rock properties and predicting waveforms based on the ultrasonic transmission method provided for the embodiments of the present disclosure. As Figure 1 shown, the system for detecting rock properties and predicting waveforms based on the ultrasonic transmission method may include: an ultrasonic transmitting device 101, an ultrasonic receiving device 102, a data acquisition and processing unit 103, and a waveform prediction unit 104.

[0028] Among them, the ultrasonic transmitting device 101 is used to transmit a first ultrasonic signal based on set transmission parameters for testing the first propagation distance. Exemplarily, the ultrasonic transmitting device 101 can adopt a piston-shaped transducer, and the signal excitation unit is used to excite the ultrasonic transmitting device 101 to transmit the first ultrasonic signal, which can generate a stable and frequency-controllable ultrasonic signal. Its central frequency and radius can be selected according to experimental requirements. For example, the central frequency can be 1 MHz and the radius can be 12.5 mm.

[0029] The ultrasonic receiving device 102 is used to receive the first ultrasonic signal that has passed through the rock sample to be tested. The ultrasonic transmitting device and the ultrasonic receiving device are located on both sides of the rock sample to be tested. Exemplarily, the ultrasonic receiving device 102 can adopt a piston-shaped transducer, which is matched with the ultrasonic transmitting device 101 and is used to receive the ultrasonic signal that has passed through the rock sample to be tested. Exemplarily, the rock sample to be tested can be sandstone, but is not limited thereto. For example, it can also be other types of rocks. The rock sample to be tested can be subjected to pretreatment such as cutting, cleaning, and drying to ensure the consistency of experimental conditions. The ultrasonic transmitting device 101 and the ultrasonic receiving device 102 are respectively placed on both sides of the rock sample to be tested, and the positions and parameters of the devices are adjusted to ensure effective signal transmission. The ultrasonic transmitting device 101 is started to transmit ultrasonic signals of different frequencies, and the first ultrasonic signal that has passed through the rock sample to be tested is received by the ultrasonic receiving device 102.

[0030] The data acquisition and processing unit 103 is used to acquire the first ultrasonic signal received by the ultrasonic receiving device, preprocess the acquired first ultrasonic signal, and determine the characteristic information of the rock sample to be tested at the first propagation distance according to the preprocessed first ultrasonic signal. Among them, the characteristic information can include but is not limited to at least one of the propagation speed, attenuation coefficient, and velocity dispersion of ultrasonic waves in the rock sample to be tested. The optional implementation manner of determining the characteristic information of the rock sample to be tested at the first propagation distance can refer to the description of the embodiments of the rock characteristic detection and waveform prediction method based on the ultrasonic transmission method below, and will not be elaborated here.

[0031] Exemplarily, the data acquisition and processing unit 103 can preprocess the acquired first ultrasonic signal, such as removing background noise, performing necessary signal conversion, signal enhancement, etc., and determine the characteristic information of the rock sample to be tested at the first propagation distance according to the preprocessed first ultrasonic signal, such as the propagation speed, attenuation coefficient, velocity dispersion, etc. of ultrasonic waves in the rock sample to be tested.

[0032] A waveform prediction unit 104 is configured to predict the ultrasonic waveform of a rock sample to be measured at a second propagation distance based on characteristic information and a preset waveform prediction model. Exemplarily, the waveform prediction unit 104 may predict the ultrasonic waveform of the rock sample to be measured at the second propagation distance based on the propagation speed, attenuation coefficient, and velocity dispersion of ultrasonic waves in the rock sample to be measured, in combination with a specific waveform prediction model, considering frictional and scattering attenuation and the Kramers-Kronig relation. For the optional implementation manners of the waveform prediction unit 104 to predict the ultrasonic waveform of the rock sample to be measured at the second propagation distance, reference may be made to the description of the embodiments of the rock characteristic detection and waveform prediction method based on the ultrasonic transmission method below, which will not be elaborated herein.

[0033] Figure 2 The figure is a schematic flowchart of the rock characteristic detection and waveform prediction method based on the ultrasonic transmission method provided by the embodiments of the present disclosure. It should be noted that in some embodiments, the rock characteristic detection and waveform prediction method based on the ultrasonic transmission method may be implemented based on the rock characteristic detection and waveform prediction system as shown in Figure 1 as above. As shown in Figure 2 as above, the rock characteristic detection and waveform prediction method may include but is not limited to the following steps.

[0034] In step 201, a control signal excitation unit excites an ultrasonic wave transmitting device to transmit a first ultrasonic wave signal based on set transmission parameters for testing at a first propagation distance.

[0035] In step 202, the ultrasonic wave receiving device receives the first ultrasonic wave signal that has passed through the rock sample to be measured. The ultrasonic wave transmitting device and the ultrasonic wave receiving device are respectively located on both sides of the rock sample to be measured.

[0036] In step 203, the first ultrasonic wave signal received by the ultrasonic wave receiving device is collected, and the collected first ultrasonic wave signal is preprocessed. The preprocessing may include, for example, removing background noise, performing necessary signal conversion, signal enhancement, and other operations.

[0037] In step 204, based on the preprocessed first ultrasonic wave signal, the characteristic information of the rock sample to be measured at the first propagation distance is determined.

[0038] In some embodiments, the above characteristic information may include at least one of the propagation speed, attenuation coefficient, and velocity dispersion of ultrasonic waves in the rock sample to be measured.

[0039] Exemplarily, the characteristic information includes, for example, the propagation speed of ultrasonic waves in the rock sample to be measured. Optional implementation manners for determining the propagation speed are as follows: Based on the preprocessed first ultrasonic signal and the arrival time of the picked first ultrasonic signal, the first ultrasonic signal passes through the rock sample to be measured, the ultrasonic wave transmitting device, and the ultrasonic wave receiving device; determine the arrival time of the second ultrasonic signal, where the second ultrasonic signal is emitted by the ultrasonic wave transmitting device when no rock sample to be measured is placed between the ultrasonic wave transmitting device and the ultrasonic wave receiving device, and the emission parameters associated with the second ultrasonic signal are the same as those associated with the first ultrasonic signal; determine the arrival time of the first synchronization signal and the arrival time of the second synchronization signal; based on the arrival time of the first ultrasonic signal, the arrival time of the second ultrasonic signal, the arrival time of the first synchronization signal, the arrival time of the second synchronization signal, and the thickness of the rock sample to be measured, determine the propagation speed of ultrasonic waves in the rock sample to be measured. Among them, the above first synchronization signal may be the synchronization signal of the first ultrasonic signal, and this first synchronization signal may be a synchronization signal directly sent by the ultrasonic wave transmitting device to the data acquisition and processing unit when a rock sample to be measured is placed between the ultrasonic wave transmitting device and the ultrasonic wave receiving device. This second synchronization signal may be the synchronization signal of the second ultrasonic signal, and this second synchronization signal may be a synchronization signal directly sent by the ultrasonic wave transmitting device to the data acquisition and processing unit when no rock sample to be measured is placed between the ultrasonic wave transmitting device and the ultrasonic wave receiving device.

[0040] For example, in the sample preparation stage, a rock sample to be measured (such as sandstone) and a reference sample (such as aluminum or a material with approximately no attenuation) can be selected. The rock sample to be measured is preprocessed, such as being cut, cleaned, and dried, to ensure the consistency of experimental conditions. For example, a sandstone sample can be collected from a specific location, cut into blocks of appropriate size, and then dried in an oven at 80 °C to remove factors such as moisture that may affect the experimental results. In the experimental operation stage, the preprocessed rock sample to be measured can be placed on the experimental bench, with an ultrasonic wave transmitting device fixed on one side of the rock sample to be measured and an ultrasonic wave receiving device fixed on the other side, ensuring that their axes are aligned. Set the parameters of the ultrasonic wave transmitting device, such as the center frequency (or emission frequency) being 1 MHz and the radius being 12.5 mm, and then perform tests at different propagation distances in sequence. Each time a test is performed, record the waveform signal received by the ultrasonic wave receiving device. Transmit the collected waveform signal to the data acquisition and processing unit, and the data acquisition and processing unit performs preprocessing operations on the waveform signal, such as noise removal and signal enhancement, and calculates relevant parameters of the waveform signal, such as the propagation speed of ultrasonic waves in the rock sample to be measured, the attenuation coefficient, and velocity dispersion.

[0041] In an embodiment of the present disclosure, the arrival time of the waveform signal can be picked, and the propagation speed of ultrasonic waves in the rock sample to be measured can be calculated using the following formula:

[0042] (1)

[0043] Wherein, is the propagation speed of ultrasonic waves in the rock sample to be measured; is the arrival time of the first ultrasonic signal of; is the arrival time of the second ultrasonic signal; is the arrival time of the first synchronization signal; is the arrival time of the second synchronization signal; L is the thickness of the rock sample to be measured.

[0044] In an embodiment of the present disclosure, the characteristic information includes, for example, an attenuation coefficient. An optional implementation for determining the attenuation coefficient is as follows: The spectrum of ultrasonic waves after passing through the rock sample to be measured can be obtained based on the preprocessed first ultrasonic signal; the spectrum of ultrasonic waves after passing through the reference sample is determined; based on the spectrum of ultrasonic waves after passing through the rock sample to be measured and the spectrum of ultrasonic waves after passing through the reference sample, the amplitude spectrum ratio is determined, and diffraction correction is performed on the amplitude spectrum ratio; based on the relationship between the diffraction-corrected amplitude spectrum ratio and frequency, the attenuation coefficient of the rock sample to be measured is obtained. In a possible implementation, the relationship between the diffraction-corrected amplitude spectrum ratio and frequency is expressed as follows:

[0045] (2)

[0046] Wherein, is the diffraction-corrected amplitude spectrum ratio, is the attenuation coefficient, including the frictional attenuation coefficient and the scattering attenuation coefficient , ω is the angular frequency, is the center frequency, is the reference frictional attenuation coefficient, is the reference scattering attenuation coefficient; is the diffraction factor associated with the rock sample to be measured, which can be obtained by solving the elastic wave equation of the ultrasonic transducer source of the corresponding shape. This factor is mainly related to the transducer size, ultrasonic wave velocity, and propagation distance. z is the propagation distance; is the transmission coefficient of the rock sample to be measured, is the transmission coefficient of the reference sample, is a constant; is the spectrum of ultrasonic waves after passing through the rock sample to be measured, is the spectrum of ultrasonic waves after passing through the reference sample; is the diffraction factor associated with the reference sample.

[0047] Exemplarily, the relationship between the amplitude spectrum ratio after diffraction correction and frequency (i.e., formula (2)) can be obtained through the following derivation:

[0048] Using the spectral ratio method, the signal spectrum of the rock sample to be measured is compared with the spectrum of the reference sample to calculate the attenuation coefficient. However, it is necessary to first perform diffraction correction using formula (2) to eliminate the influence of diffraction effects on attenuation measurement. Usually, the spectrum of the waveform after ultrasonic waves pass through the rock can be expressed as:

[0049] (3)

[0050] Where, is the wave number and can be expressed as , a is the diameter of the ultrasonic emission device or ultrasonic receiving device, for example, it can be the diameter of the transducer; z is the propagation distance; is the transducer transfer function, ω is the angular frequency. Where, η ( ω ) is the attenuation coefficient. The attenuation of dry rock mainly comes from frictional dissipation and scattering attenuation. Therefore, η ( ω ) can be expressed as the sum of the two: , the frictional attenuation coefficient can be approximately expressed as: , the scattering attenuation coefficient can be approximately expressed as: .

[0051] is the measured attenuation of the rock. In the laboratory, a non-attenuating material (such as aluminum) with the same length as the rock sample to be measured can be used as the reference sample, and then the ratio of the two spectra is used for calculation. Let the spectrum of the rock sample to be measured be , and the spectrum of the reference sample be , then the logarithm of the ratio of the amplitude spectra of the two can be expressed as:

[0052] (4)

[0053] Where, represents the diffraction factor and can be expressed by formula (5), represents the transmission coefficient, and the third term in formula (4) is a constant.

[0054] (5)

[0055] According to formula (5), It is greatly affected by velocity but less affected by attenuation. Substituting it into Equation (4) and rearranging the terms, the corrected amplitude spectrum can be obtained as shown in the above Equation (2), which is the relationship between the diffracted-corrected amplitude spectrum ratio and frequency. According to the above Equation (2), the attenuation coefficient of the rock sample to be measured can be approximately obtained from the relationship between the diffracted-corrected amplitude spectrum ratio and frequency.

[0056] In an embodiment of the present disclosure, the characteristic information includes, for example, the velocity dispersion of ultrasonic waves in the rock sample to be measured. An optional implementation for determining the velocity dispersion is as follows: based on the propagation velocity and attenuation coefficient of ultrasonic waves in the rock sample to be measured, the Kramers-Kronig relationship is used to determine the velocity dispersion of ultrasonic waves in the rock sample to be measured. Exemplarily, the calculation formula for the velocity dispersion of ultrasonic waves in the rock sample to be measured is expressed as follows:

[0057] (6)

[0058] where is the velocity dispersion of ultrasonic waves in the rock sample to be measured; is the first arrival wave velocity, which can be obtained based on the propagation velocity; is the attenuation coefficient; ω is the angular frequency, is the center frequency.

[0059] In step 205, based on the characteristic information and a preset waveform prediction model, the ultrasonic waveform of the rock sample to be measured at the second propagation distance is predicted.

[0060] Exemplarily, the calculated relevant parameters such as the propagation velocity, dispersion, and attenuation coefficient can be substituted into the preset waveform prediction model to predict the ultrasonic waveforms at different propagation distances (such as the second propagation distance) using the waveform after the first propagation distance. In some embodiments, the formula of the waveform prediction model can be expressed as follows:

[0061] (7)

[0062] where is the predicted ultrasonic waveform at the second propagation distance ; is the inverse Fourier transform; is the first propagation distance ; is the geometric propagation factor, which reflects the propagation of ultrasonic waves in the medium; is the diffraction correction factor, which is used to correct the change in diffracted energy caused by the shape of the transducer source; is the attenuation coefficient; is the velocity dispersion of ultrasonic waves in the rock sample to be measured.

[0063] The following will be combined with Figure 3 Taking sandstone as an example, the experimental process will be described in detail.

[0064] (1) Sample selection and treatment

[0065] Collect sandstone samples from a specific location, cut them into blocks of appropriate size, and then dry them in an oven at 80 °C to remove moisture and other factors that may affect the experimental results.

[0066] (2) Experimental operations

[0067] Place the treated sandstone sample on the experimental bench, fix the ultrasonic transmitting device on one side of the sample and the receiving device on the other side, ensuring that their axes are aligned. Set the parameters of the ultrasonic transmitting device, such as the transmitting frequency of 1 MHz, and then conduct tests at different propagation distances in sequence. Record the waveform signals received by the ultrasonic receiving device during each test.

[0068] (3) Data processing and analysis

[0069] Transmit the collected waveform signals to the data acquisition and processing unit for preprocessing operations such as noise removal and signal enhancement. Calculate the propagation velocity, measure the attenuation, and calculate the dispersion according to the above-mentioned method for detecting rock properties and predicting waveforms based on the ultrasonic transmission method. Use the calculated propagation velocity, dispersion, and attenuation coefficient to predict the waveform, and finally obtain the predicted ultrasonic waveform. Compare the prediction results (i.e., the predicted ultrasonic waveform) with the actually measured waveform, analyze the differences, and evaluate the accuracy of the system and method.

[0070] It should be noted that during the experimental process, maintain the stability of the experimental environment (temperature, humidity, etc.), ensure good contact between the transducer and the sample surface, etc., to ensure the reliability of the experimental results.

[0071] In summary, by optimizing the experimental method and data processing process, it is possible to more accurately measure the velocity, dispersion, and attenuation characteristics of rocks, reduce measurement errors, and thus improve the detection accuracy. Based on the improved theoretical model (i.e., the waveform prediction model), the present disclosure can more accurately predict the ultrasonic waveforms of different types of rocks (especially sandstone, etc.) at different propagation distances, providing a strong basis for in-depth understanding of the internal structure and characteristics of rocks. Optionally, the solutions involved in the present disclosure can be applied to multiple fields such as geological exploration, mine exploitation, and petroleum engineering, helping to improve the efficiency of resource exploration, evaluate the rock stability, etc., and having important economic and engineering values.

[0072] In the description of this specification, the descriptions with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc., mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present disclosure. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0073] In the description of the present disclosure, the meaning of "at least one" is one or more, and the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise specifically defined.

[0074] Any process or method description shown in a flowchart or described in other ways herein may be understood to represent a module, segment, or portion of code including one or more executable instructions for implementing a customized logic function or process, and the scope of the preferred embodiments of the present disclosure includes additional implementations, where the functions may be executed in a substantially simultaneous manner or in a reverse order according to the involved functions, rather than in the order shown or discussed, which should be understood by those skilled in the art to which the embodiments of the present disclosure pertain.

[0075] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a definable sequence list of executable instructions for implementing logical functions, and can be specifically implemented in any computer-readable medium for use by an instruction execution system, apparatus, or device (such as a computer-based system, a system including a processor, or other systems that can fetch and execute instructions from the instruction execution system, apparatus, or device), or in conjunction with these instruction execution systems, apparatus, or devices. For the purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by or in conjunction with an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include the following: an electrical connection portion having one or more wirings (electronic device), a portable computer diskette (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable medium can even be paper or other suitable media on which the program can be printed, because the program can be obtained electronically, for example, by optically scanning the paper or other media, followed by editing, interpretation, or otherwise processing as appropriate, and then storing it in a computer memory.

[0076] It should be understood that various parts of the present disclosure can be implemented by hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, any one or a combination of the following techniques well known in the art can be used: discrete logic circuits having logic gate circuits for implementing logical functions on data signals, application specific integrated circuits having appropriate combinational logic gate circuits, programmable gate arrays (PGA), field programmable gate arrays (FPGA), etc.

[0077] Those of ordinary skill in the art of this technology can understand that all or part of the steps carried by the method of implementing the above embodiments can be completed by instructing relevant hardware through a program, and the program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiments.

[0078] In addition, in various embodiments of the present disclosure, each functional unit may be integrated in a processing module, may exist separately physically for each unit, or two or more units may be integrated in one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. When the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0079] The above-mentioned storage medium may be a read-only memory, a magnetic disk or an optical disc, etc. Although the embodiments of the present disclosure have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present disclosure. Those of ordinary skill in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present disclosure.

Claims

1. A method for detecting rock properties and predicting waveforms based on the ultrasonic transmission method, characterized in that, Including: The control signal excitation unit excites the ultrasonic transmitting device to transmit a first ultrasonic signal based on set transmission parameters for testing the first propagation distance; The first ultrasonic signal passing through the rock sample to be measured is received by the ultrasonic receiving device, and the ultrasonic transmitting device and the ultrasonic receiving device are located on both sides of the rock sample to be measured; Collect the first ultrasonic signal received by the ultrasonic receiving device, and preprocess the collected first ultrasonic signal; According to the preprocessed first ultrasonic signal, determine the characteristic information of the rock sample to be measured at the first propagation distance, where the characteristic information includes at least one of the propagation speed, attenuation coefficient, and velocity dispersion of ultrasonic waves in the rock sample to be measured; Based on the characteristic information and a preset waveform prediction model, predict the ultrasonic waveform of the rock sample to be measured at the second propagation distance; where the formula of the waveform prediction model is as follows: wherein, is the predicted second propagation distance of the ultrasonic waveform; is the inverse Fourier transform; is the ultrasonic waveform at the first propagation distance; is the geometric propagation factor, reflecting the propagation of ultrasonic waves in the medium; is the diffraction correction factor, used to correct the change in diffracted energy caused by the shape of the transducer source; is the attenuation coefficient; is the velocity dispersion of the ultrasonic wave in the rock sample to be measured.

2. The method according to claim 1, wherein The determining the characteristic information of the rock sample to be measured at the first propagation distance according to the preprocessed first ultrasonic signal includes: According to the preprocessed first ultrasonic signal, pick up the arrival time of the first ultrasonic signal, and the first ultrasonic signal passes through the rock sample to be measured, the ultrasonic transmitting device and the ultrasonic receiving device; Determine the arrival time of the second ultrasonic signal, where the second ultrasonic signal is transmitted by the ultrasonic transmitting device when the rock sample to be measured is not placed between the ultrasonic transmitting device and the ultrasonic receiving device, and the transmission parameters associated with the second ultrasonic signal are the same as those associated with the first ultrasonic signal; Determine the arrival time of the first synchronization signal and the arrival time of the second synchronization signal; where the first synchronization signal is the synchronization signal of the first ultrasonic signal, and the second synchronization signal is the synchronization signal of the second ultrasonic signal; According to the arrival time of the first ultrasonic signal, the arrival time of the second ultrasonic signal, the arrival time of the first synchronization signal, the arrival time of the second synchronization signal, and the thickness of the rock sample to be measured, determine the propagation speed of ultrasonic waves in the rock sample to be measured.

3. The method according to claim 2, characterized in that, The calculation formula of the propagation speed of ultrasonic waves in the rock sample to be measured is as follows: Wherein, is the propagation speed of ultrasonic waves in the rock sample to be measured; is the arrival time of the first ultrasonic signal; is the arrival time of the second ultrasonic signal; is the arrival time of the first synchronization signal; is the arrival time of the second synchronization signal; L is the thickness of the rock sample to be measured.

4. The method according to claim 1, characterized in that The determining the characteristic information of the rock sample to be measured at the first propagation distance according to the preprocessed first ultrasonic signal includes: According to the preprocessed first ultrasonic signal, obtain the spectrum of ultrasonic waves after passing through the rock sample to be measured; Determine the spectrum of ultrasonic waves after passing through the reference sample; According to the spectrum of ultrasonic waves after passing through the rock sample to be measured and the spectrum of ultrasonic waves after passing through the reference sample, determine the amplitude spectrum ratio, and perform diffraction correction on the amplitude spectrum ratio; Based on the relationship between the diffraction-corrected amplitude spectrum ratio and frequency, obtain the attenuation coefficient of the rock sample to be measured.

5. The method according to claim 4, characterized in that, The relationship between the diffraction-corrected amplitude spectrum ratio and frequency is expressed as follows: Wherein, is the amplitude spectrum ratio after diffraction correction, is the attenuation coefficient, including the frictional attenuation coefficient and the scattering attenuation coefficient , ω is the angular frequency, is the central frequency, is the reference frictional attenuation coefficient, is the reference scattering attenuation coefficient; is the diffraction factor associated with the rock sample to be measured; z is the propagation distance; is the transmission coefficient of the rock sample to be measured, is the transmission coefficient of the reference sample, is a constant; is the frequency spectrum after the ultrasonic wave passes through the rock sample to be measured, is the frequency spectrum after the ultrasonic wave passes through the reference sample; is the diffraction factor associated with the reference sample.

6. The method according to claim 1, wherein Determining the characteristic information of the rock sample to be measured at the first propagation distance according to the preprocessed first ultrasonic signal includes: Determining the velocity dispersion of ultrasonic waves in the rock sample to be measured by using the Kramers-Kronig relationship based on the propagation velocity and the attenuation coefficient of the ultrasonic waves in the rock sample to be measured.

7. The method according to claim 6, characterized in that The calculation formula for the velocity dispersion of ultrasonic waves in the rock sample to be measured is expressed as follows: wherein, is the velocity dispersion of the ultrasonic wave in the rock sample to be measured; is the first arrival wave velocity; is the attenuation coefficient; ω is the angular frequency, is the center frequency.

8. A rock property detection and waveform prediction system based on the ultrasonic transmission method, characterized in that, Including: An ultrasonic wave transmitting device, configured to transmit a first ultrasonic signal based on set transmission parameters to perform a test of the first propagation distance; An ultrasonic wave receiving device, configured to receive the first ultrasonic signal passing through the rock sample to be measured, wherein the ultrasonic wave transmitting device and the ultrasonic wave receiving device are located on both sides of the rock sample to be measured; A data acquisition and processing unit, configured to acquire the first ultrasonic signal received by the ultrasonic wave receiving device, preprocess the acquired first ultrasonic signal, and determine the characteristic information of the rock sample to be measured at the first propagation distance according to the preprocessed first ultrasonic signal, where the characteristic information includes at least one of the propagation velocity, attenuation coefficient, and velocity dispersion of ultrasonic waves in the rock sample to be measured; A waveform prediction unit, configured to predict the ultrasonic waveform of the rock sample to be measured at a second propagation distance based on the characteristic information and a preset waveform prediction model; wherein, the formula of the waveform prediction model is expressed as follows: Among them, is the predicted second propagation distance of the ultrasonic waveform; is the inverse Fourier transform; is the ultrasonic waveform at the first propagation distance; is the geometric propagation factor, reflecting the propagation of ultrasonic waves in the medium; is the diffraction correction factor, used to correct the change in diffracted energy caused by the shape of the transducer source; is the attenuation coefficient; is the velocity dispersion of the ultrasonic wave in the rock sample to be measured.

9. The system according to claim 8, wherein The data acquisition and processing unit is configured to: Obtain the spectrum of the ultrasonic waves after passing through the rock sample to be measured according to the preprocessed first ultrasonic signal; Determine the spectrum of the ultrasonic waves after passing through the reference sample; Determine the amplitude spectrum ratio according to the spectrum of the ultrasonic waves after passing through the rock sample to be measured and the spectrum of the ultrasonic waves after passing through the reference sample, and perform diffraction correction on the amplitude spectrum ratio; Obtain the attenuation coefficient of the rock sample to be measured based on the relationship between the diffractively corrected amplitude spectrum ratio and the frequency.

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