Active detection type dangerous rock collapse monitoring method and device

Abstract

The invention provides an active detection type dangerous rock collapse monitoring method and device, belongs to the field of dangerous rock monitoring, and is used for solving the problem of poor reliability of a dangerous rock collapse monitoring technology in related technologies. In the method and device, a monitoring excitation signal is determined according to at least one local oscillation frequency of a pre-acquired target dangerous rock body; the monitoring excitation signal comprises a plurality of excitation frequency ranges in one-to-one correspondence with local oscillation frequencies; determining an excellent frequency relative to each excitation frequency range according to a monitoring echo signal of a target dangerous rock body under the monitoring excitation signal; judging whether the predominant frequency exceeds a pre-acquired confidence frequency range or not; and if yes, generating a collapse early warning signal. By adopting the technical scheme, whether the state of the target dangerous rock body is changed or not can be intelligently and reasonably determined, namely whether the target dangerous rock body has the collapse risk or not, so that the collapse of the target dangerous rock body can be reliably monitored.

Description

Technical Field

[0001] The present application relates to the field of dangerous rock monitoring, and in particular to an active detection type dangerous rock collapse monitoring method and device. Background Art

[0002] Dangerous rock mass refers to a potential collapse body, which is usually located in a mountain spur with a large height difference, isolated and steep, or a concave steep slope. It has developed internal cracks, incomplete rock structure, and a large number of cracks or weak zones that extend in line with or parallel to the slope. In order to deal with the possible hazards caused by the collapse of dangerous rocks, it is generally necessary to use monitoring devices to monitor dangerous rocks so that relevant personnel can be notified in time to take measures when there are signs of collapse of dangerous rocks. If the reliability of the monitoring device is insufficient, the monitoring of dangerous rock collapse may be untimely and inaccurate, resulting in the inability to deal with the possible hazards caused by the collapse of dangerous rocks in a timely and effective manner. Summary of the invention

[0003] The present application provides an active detection type dangerous rock collapse monitoring method and device, which is conducive to reliable monitoring of dangerous rock collapse.

[0004] In a first aspect, the present application provides an active detection type dangerous rock collapse monitoring method. The method comprises: Determine a monitoring excitation signal according to at least one local oscillation frequency of the target dangerous rock mass acquired in advance, wherein the monitoring excitation signal includes a plurality of excitation frequency ranges corresponding to the local oscillation frequencies one by one; According to the monitoring echo signal of the target dangerous rock mass under the monitoring excitation signal, a dominant frequency is determined relative to each excitation frequency range; Determining whether the superior frequency exceeds a pre-acquired confidence frequency range; If so, a collapse warning signal is generated.

[0005] By adopting the above technical solution, it is possible to intelligently and reasonably determine whether the state of the target dangerous rock mass has changed, that is, whether the target dangerous rock mass has a risk of collapse, thereby enabling reliable monitoring of the collapse of the target dangerous rock mass.

[0006] Furthermore, the excitation frequency range takes the corresponding local oscillation frequency as a midpoint.

[0007] Furthermore, the method for acquiring at least one local oscillation frequency of the target dangerous rock mass includes: Acquire a detection echo signal of the target dangerous rock mass under a detection excitation signal, wherein the frequency range of the detection excitation signal is wider than the frequency range of the monitoring excitation signal; Perform spectrum analysis on the detection echo signal to obtain multiple frequency point data and amplitude data corresponding to each frequency point data. Assume that there are n frequency point data and the i-th frequency point data is , the corresponding amplitude data is ; Determine the frequency point data whose amplitude data is higher than the preset amplitude and whose amplitude data is the maximum value as the local oscillation frequency, and set the preset amplitude as , the local oscillator frequency is , then the relative local oscillator frequency of satisfy ,and ,and .

[0008] Furthermore, the method for obtaining the confidence frequency range includes: Acquire historical monitoring records of the target dangerous rock mass, wherein the historical monitoring records include historical outstanding frequencies with timestamps; Determine the distribution frequency range based on the historical superior frequency distribution within a preset time period; The confidence frequency range is determined according to the distribution frequency range, the center of the confidence frequency range is the same as the center of the distribution frequency range, and the width of the confidence frequency range is a preset multiple of the distribution frequency range.

[0009] Furthermore, determining the distribution frequency range according to the historical excellent frequency distribution within a preset time period includes: Calculate the frequency average of the historical excellent frequencies within the preset time length. Suppose there are i historical excellent frequencies within the preset time length, and the i-th historical excellent frequency is The average frequency is , ; Based on the pre-built range determination model, the distribution frequency range is determined according to the frequency average value and the historical excellent frequency within the preset time length. The frequency average value is the center of the distribution frequency range. The distribution frequency range covers a specified number of historical excellent frequencies within the preset time length. The lower limit of the distribution frequency range is set to , the upper limit of the range is , The historical superior frequencies are within the distribution frequency range, and the specified quantity ratio is ,but .

[0010] Further, it also includes: determining the hazard data of the target dangerous rock mass according to the historical superior frequency; The hazard data of the target dangerous rock mass determined according to the historical superior frequency include: Let the historical moment before the preset time length of the current moment be the first historical moment, the historical moment before twice the preset time length of the current moment be the second historical moment, and the frequency average of the historical excellence frequencies between the first historical moment and the second historical moment be the preceding average frequency; Based on the range determination model, determining a front frequency range according to the front average frequency and the historical superior frequency from the first historical moment to the second historical moment; The risk data is determined according to the absolute value of the difference between the frequency average value and the preceding average frequency and the absolute value of the difference between the width of the distribution frequency range and the width of the preceding frequency range. The risk data is positively correlated with the absolute value of the difference between the frequency average value and the preceding average frequency and the absolute value of the difference between the width of the distribution frequency range and the width of the preceding frequency range. The lower limit of the preceding frequency range is set to , the upper limit of the range is , the pre-evaluation frequency is , the hazard data is z, then , where , Both are greater than zero.

[0011] In the second aspect, the present application provides an active detection type dangerous rock collapse monitoring device. The device includes a signal transmitting module, a signal receiving module and a device control module, the signal transmitting module is used to transmit an excitation signal to the target dangerous rock body, the signal receiving module is used to receive the echo signal emitted by the target dangerous rock body, and the device control module is connected to the signal transmitting module and the signal receiving module, and is used to execute any one of the methods described in the first aspect above.

[0012] Furthermore, the device control module is further configured to: Generate a wake-up signal based on the internal clock timing, wherein the wake-up signal is used to wake up the device; Based on the wake-up signal, the signal receiving module is triggered to obtain a Bunsen echo signal, where the Bunsen echo signal is an echo signal generated by the target dangerous rock body under natural conditions. If the Bunsen echo signal is obtained, the state of the target dangerous rock body is analyzed according to the Bunsen echo signal; otherwise, any one of the methods described in the first aspect above is triggered to execute.

[0013] In summary, this application at least has the following beneficial effects: Provided are an active detection type dangerous rock collapse monitoring method and device, which can intelligently and reasonably determine whether the state of a target dangerous rock body has changed, so as to reliably monitor the collapse of the target dangerous rock body.

[0014] It should be understood that the contents described in the Summary of the Invention are not intended to limit the key or important features of the embodiments of the present application, nor are they intended to limit the scope of the present application. Other features of the present application will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The above and other features, advantages and aspects of the embodiments of the present application will become more apparent with reference to the following detailed description in conjunction with the accompanying drawings. In the accompanying drawings, the same or similar reference numerals represent the same or similar elements, wherein: Figure 1 A block diagram of an active detection type dangerous rock collapse monitoring device in an embodiment of the present application is shown; Figure 2 A flow chart of an active detection type dangerous rock collapse monitoring method in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0017] In addition, the term "and / or" in this article is only a description of the association relationship between the associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0018] The present application provides an active detection type dangerous rock collapse monitoring method and device, which can intelligently and reasonably determine whether the state of a target dangerous rock body has changed, so as to reliably monitor the collapse of the target dangerous rock body.

[0019] In a first aspect, the present application provides an active detection type dangerous rock collapse monitoring device.

[0020] Figure 1 A block diagram of an active detection type dangerous rock collapse monitoring device in an embodiment of the present application is shown.

[0021] Reference Figure 1 The device includes a signal transmitting module 110, a signal receiving module 120 and a device control module 130.

[0022] Among them, the signal transmitting module 110 is used to transmit an excitation signal to the target dangerous rock body. The signal transmitting module 110 may specifically include a transmitting driving current and a transmitting transducer. The transmitting transducer is used to attach to the target dangerous rock body to transmit the excitation signal to the target dangerous rock body; the signal receiving module 120 is used to receive the echo signal emitted by the target dangerous rock body. The signal receiving module 120 includes a receiving transducer and a receiving amplification circuit. The receiving transducer is used to attach to the target dangerous rock body to receive the echo signal emitted by the target dangerous rock body.

[0023] The device control module 130 is connected to the signal transmitting module 110 and the signal receiving module 120, and is used to control the signal transmitting module 110 to transmit an excitation signal to the target dangerous rock mass and receive the echo signal collected by the signal receiving module 120, so as to analyze the state of the target dangerous rock mass and realize reliable monitoring of dangerous rock collapse.

[0024] The device control module 130 has a built-in clock. The device control module 130 generates a wake-up signal based on the built-in clock. After generating the wake-up signal, the device control module 130 first controls the signal receiving module 120 to obtain the Bunsen echo signal. The Bunsen echo signal is an echo signal generated by the target dangerous rock body under natural conditions, such as an echo signal caused by vibration under the influence of natural wind or internal structure changes. If the Bunsen echo signal is obtained, the state of the target dangerous rock body is analyzed according to the Bunsen echo signal.

[0025] The device control module 130 can determine the state change of the target dangerous rock mass based on the maximum amplitude and frequency distribution of the Bunsen echo signal, and generate a dangerous rock collapse warning signal when the maximum amplitude exceeds the amplitude threshold and / or the frequency distribution exceeds the preset distribution rule.

[0026] When the device control module 130 fails to obtain the Bunsen echo signal, the trigger signal transmitting module 110 and the signal receiving module 120 work together and use an intelligent algorithm to determine the pile of the target dangerous rock mass. The intelligent algorithm is introduced based on the disclosure of the second aspect of the present application.

[0027] In a second aspect, the present application provides an active detection type dangerous rock collapse monitoring method. The method can be Figure 1 The device control module 130 in is executed.

[0028] Figure 2 A flow chart of an active detection type dangerous rock collapse monitoring method in an embodiment of the present application is shown.

[0029] Reference Figure 2 , the method specifically comprises the following steps: S210: Determine a monitoring excitation signal according to at least one local oscillation frequency of the pre-acquired target dangerous rock mass.

[0030] The monitoring excitation signal includes an excitation frequency range corresponding to the local oscillator frequency one by one; the excitation frequency range takes the corresponding local oscillator frequency as the midpoint. In the embodiment of the present application, the excitation frequency range is equal to 0.9 times the local oscillator frequency to 1.1 times the local oscillator frequency.

[0031] In the method of this step, the method for obtaining at least one local oscillation frequency of the target dangerous rock body includes: obtaining a detection echo signal of the target dangerous rock body under a detection excitation signal, wherein the frequency range of the detection excitation signal is wider than the frequency range of the monitoring excitation signal; performing spectrum analysis on the detection echo signal to obtain multiple frequency point data and amplitude data corresponding to each frequency point data, assuming that there are n frequency point data, and the i-th frequency point data is , the corresponding amplitude data is ; Determine the frequency point data whose amplitude data is higher than the preset amplitude and whose amplitude data is the maximum value as the local oscillation frequency, and set the preset amplitude to , the local oscillator frequency is , then the relative local oscillator frequency of satisfy ,and ,and .

[0032] The detection excitation signal is a wide-band excitation signal, and the corresponding detection echo signal is also a wide-band excitation signal. After performing fast Fourier transform on the detection echo signal, the amplitude data and phase data of each frequency point can be determined.

[0033] After determining the amplitude data and phase data of each frequency point, a two-dimensional coordinate system is constructed with the frequency point information as the horizontal axis and the amplitude data as the vertical axis, and all the frequency point data and the corresponding amplitude data are substituted to obtain a number of coordinate points; all the coordinate points are connected in order with a smooth curve to obtain a frequency amplitude distribution curve; the maximum value of the frequency amplitude distribution curve is analyzed and determined, and whether the vertical coordinate of each maximum value is higher than the preset amplitude, if so, the corresponding frequency point data is taken as the local oscillation frequency. In this way, one or more local oscillation frequencies can be obtained.

[0034] The excitation frequency ranges corresponding to different local oscillator frequencies do not overlap.

[0035] S220: Determine a dominant frequency relative to each excitation frequency range according to the monitoring echo signal of the target dangerous rock mass under the monitoring excitation signal.

[0036] Since the monitoring excitation signal has an excitation frequency range that corresponds one-to-one to the local oscillation frequency, and the monitoring echo signal is the echo signal under the monitoring excitation signal, the monitoring echo signal can also be divided according to the excitation frequency range.

[0037] A superior signal can be determined in the frequency range of each excitation frequency range corresponding to the monitoring echo signal. The specific determination method is to perform fast Fourier transform on the part of the monitoring echo signal corresponding to the excitation frequency range to obtain frequency point data and corresponding amplitude data and phase data, and determine the frequency point data with the highest amplitude data as the superior frequency in the corresponding excitation frequency range.

[0038] S230: Determine whether the dominant frequency exceeds a pre-acquired confidence frequency range.

[0039] In the method of this step, it is first necessary to obtain a confidence frequency range, and the method for obtaining the confidence frequency range includes: obtaining historical monitoring records of the target dangerous rock body, the historical monitoring records including historical outstanding frequencies with timestamps; determining a distribution frequency range based on the distribution of historical outstanding frequencies within a preset time length; determining the confidence frequency range based on the distribution frequency range, the center of the confidence frequency range is the same as the center of the distribution frequency range, and the width of the confidence frequency range is a preset multiple of the distribution frequency range.

[0040] The historical monitoring records are monitoring records stored in the device or uploaded to the host computer. The historical monitoring records include historical superior frequencies with timestamps. A historical superior frequency has multiple superior frequencies that correspond to the excitation frequency range of the local oscillator frequency. Each superior frequency can be analyzed independently.

[0041] In the above content, determining the distribution frequency range according to the historical excellent frequency distribution within the preset time length includes: calculating the frequency average of the historical excellent frequencies within the preset time length, assuming that there are i historical excellent frequencies within the preset time length, and the i-th historical excellent frequency is The average frequency is , Based on the pre-built range determination model, the distribution frequency range is determined according to the frequency average value and the historical excellent frequency within the preset time length, the frequency average value is the center of the distribution frequency range, and the distribution frequency range covers a specified number of historical excellent frequencies within the preset time length. The lower limit of the distribution frequency range is set to , the upper limit of the range is , The historical superior frequencies are within the distribution frequency range, and the specified quantity ratio is ,but .

[0042] Specifically, the distribution frequency range is constructed with the frequency average as the center, so that a specified number of historical excellent frequencies within a preset time length are within the distribution frequency range, and the distribution frequency range carries confidence data, and the confidence data is equal to the specified number ratio.

[0043] In one example, the preset duration is 30 days, there is one historical monitoring record every day, and the specified quantity ratio is 95%, which means taking 0.95 times the total quantity, which is 28.5, rounded down to 28. Each historical monitoring record has multiple outstanding frequencies, and each outstanding frequency corresponds to a local oscillation frequency and an excitation frequency range, that is, the outstanding frequencies corresponding to a local oscillation frequency and an excitation frequency range can be analyzed independently.

[0044] Taking the outstanding frequency corresponding to the local oscillation frequency and the excitation frequency range as an example, the frequency average value of the past 30 days is first calculated, and then the distribution frequency range is constructed with the frequency average value as the center, so that the 28 historical outstanding frequencies in the past 30 days are within the distribution frequency range, and the distribution frequency range carries confidence data, and the confidence data is equal to 95%. The distribution frequency range is specifically the minimum frequency range covering the 28 historical outstanding frequencies that are closer to the frequency average value in the past 30 days.

[0045] In this example, the preset multiple is specifically set to 2, that is, the confidence frequency range is twice the width of the distribution frequency range, and the midpoint of the confidence frequency range is the frequency average.

[0046] S240: If the judgment in step S230 is yes, a collapse warning signal is generated.

[0047] For each outstanding frequency, an independent judgment can be made. That is, if the current outstanding frequency exceeds the corresponding determined confidence frequency range, it means that the state of the target dangerous rock mass has changed significantly, indicating that the target dangerous rock mass is very likely to collapse, and a collapse warning signal is generated at this time.

[0048] In addition, in order to analyze the collapse trend of the target dangerous rock mass, the method also includes: determining the hazard data of the target dangerous rock mass according to the historical superior frequency.

[0049] Specifically, the hazard data of the target dangerous rock mass determined based on the historical superior frequency include: Suppose the historical moment before the preset time length of the current moment is the first historical moment, the historical moment before twice the preset time length of the current moment is the second historical moment, the frequency average of the historical excellent frequencies between the first historical moment and the second historical moment is the preceding average frequency, based on the range determination model, determine the preceding frequency range according to the preceding average frequency and the historical excellent frequencies from the first historical moment to the second historical moment; determine the hazard data according to the absolute value of the difference between the frequency average and the preceding average frequency and the absolute value of the difference between the width of the distribution frequency range and the width of the preceding frequency range, the hazard data is positively correlated with the absolute value of the difference between the frequency average and the preceding average frequency and the absolute value of the difference between the width of the distribution frequency range and the width of the preceding frequency range, and suppose the lower limit of the preceding frequency range is , the upper limit of the range is , the pre-evaluation frequency is , the hazard data is z, then , where , Both are greater than zero.

[0050] In one example, the frequency average and distribution frequency range of the historical excellent frequency in the past 30 days are calculated first, and then the frequency average and distribution frequency range of the historical excellent frequency between the past 60 days and the past 30 days are calculated. The absolute value of the difference between the two frequency averages and the absolute value of the difference between the widths of the two distribution frequency ranges are calculated. The hazard data corresponding to the historical excellent frequency is equal to the sum of the two absolute values ​​of the difference. The larger the absolute values ​​of the two differences, the greater the cumulative change in the state of the target dangerous rock mass in the long period, which means that the target dangerous rock mass is more dangerous. Since the historical excellent frequencies correspond one-to-one to the local oscillator frequency, there may be multiple. If there are multiple historical excellent frequencies, the overall hazard data of the target dangerous rock mass is equal to the cumulative product of the hazard data of all historical excellent frequencies.

[0051] In summary, this method can realize the collapse monitoring of target dangerous rock mass, the monitoring is relatively reliable and can analyze the instantaneous state and long-term collapse trend of the target dangerous rock mass, so as to make timely and effective response to the hazards caused by the collapse of dangerous rock.

[0052] It should be noted that, for the aforementioned method embodiments, for the sake of simplicity of description, they are all expressed as a series of action combinations, but those skilled in the art should be aware that the present application is not limited by the described order of actions, because according to the embodiments of the present application, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all optional embodiments, and the actions and modules involved are not necessarily required by the present application.

[0053] In summary, this application at least has the following beneficial effects: Provided are an active detection type dangerous rock collapse monitoring method and device, which can intelligently and reasonably determine whether the state of a target dangerous rock body has changed, so as to reliably monitor the collapse of the target dangerous rock body.

[0054] The above description is only a preferred embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of disclosure involved in the present application is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the aforementioned disclosed concept. For example, the above features are replaced with the technical features with similar functions disclosed in this application (but not limited to) by each other to form a technical solution.

Claims

1. An active detection type dangerous rock collapse monitoring method, characterized in that: include: Determine a monitoring excitation signal according to at least one local oscillation frequency of the target dangerous rock mass acquired in advance, wherein the monitoring excitation signal includes a plurality of excitation frequency ranges corresponding to the local oscillation frequencies one by one; According to the monitoring echo signal of the target dangerous rock mass under the monitoring excitation signal, a dominant frequency is determined relative to each excitation frequency range; Determining whether the superior frequency exceeds a pre-acquired confidence frequency range; If so, a collapse warning signal is generated.

2. The method according to claim 1, characterized in that The excitation frequency range has the corresponding local oscillation frequency as the midpoint.

3. The method according to claim 2, characterized in that The method for acquiring at least one local oscillation frequency of the target dangerous rock mass includes: Acquire a detection echo signal of the target dangerous rock mass under a detection excitation signal, wherein the frequency range of the detection excitation signal is wider than the frequency range of the monitoring excitation signal; Perform spectrum analysis on the detection echo signal to obtain multiple frequency point data and amplitude data corresponding to each frequency point data. Assume that there are n frequency point data and the i-th frequency point data is , the corresponding amplitude data is ; Determine the frequency point data whose amplitude data is higher than the preset amplitude and whose amplitude data is the maximum value as the local oscillation frequency, and set the preset amplitude as , the local oscillator frequency is , then the relative local oscillator frequency of satisfy ,and ,and .

4. The method according to claim 3, characterized in that The method for obtaining the confidence frequency range includes: Acquire historical monitoring records of the target dangerous rock mass, wherein the historical monitoring records include historical outstanding frequencies with timestamps; Determine the distribution frequency range based on the historical superior frequency distribution within a preset time period; The confidence frequency range is determined according to the distribution frequency range, the center of the confidence frequency range is the same as the center of the distribution frequency range, and the width of the confidence frequency range is a preset multiple of the distribution frequency range.

5. The method according to claim 4, characterized in that Determining the distribution frequency range according to the historical excellent frequency distribution within a preset time period includes: Calculate the frequency average of the historical excellent frequency within the preset time length. Suppose there are i historical excellent frequencies within the preset time length, and the i-th historical excellent frequency is The average frequency is , ; Based on the pre-built range determination model, the distribution frequency range is determined according to the frequency average value and the historical excellent frequency within the preset time length. The frequency average value is the center of the distribution frequency range. The distribution frequency range covers a specified number of historical excellent frequencies within the preset time length. The lower limit of the distribution frequency range is set to , the upper limit of the range is , The historical superior frequencies are within the distribution frequency range, and the specified quantity ratio is ,but .

6. The method according to claim 5, characterized in that Also includes: Determine the hazard data of the target dangerous rock mass based on the historical superiority frequency; The hazard data of the target dangerous rock mass determined according to the historical superior frequency include: Let the historical moment before the preset time length of the current moment be the first historical moment, the historical moment before twice the preset time length of the current moment be the second historical moment, and the frequency average of the historical excellence frequencies between the first historical moment and the second historical moment be the preceding average frequency; Based on the range determination model, determining a front frequency range according to the front average frequency and the historical superior frequency from the first historical moment to the second historical moment; The risk data is determined according to the absolute value of the difference between the frequency average value and the preceding average frequency and the absolute value of the difference between the width of the distribution frequency range and the width of the preceding frequency range. The risk data is positively correlated with the absolute value of the difference between the frequency average value and the preceding average frequency and the absolute value of the difference between the width of the distribution frequency range and the width of the preceding frequency range. The lower limit of the preceding frequency range is set to , the upper limit of the range is , the pre-evaluation frequency is , the hazard data is z, then , where , Both are greater than zero.

7. An active detection type dangerous rock collapse monitoring device, characterized in that: The invention comprises a signal transmitting module (110), a signal receiving module (120) and a device control module (130), wherein the signal transmitting module (110) is used to transmit an excitation signal to a target dangerous rock body, the signal receiving module (120) is used to receive an echo signal emitted by the target dangerous rock body, and the device control module (130) is connected to the signal transmitting module and the signal receiving module to execute the method according to any one of claims 1 to 6.

8. The device according to claim 7, characterized in that The device control module (130) is further configured to: Generate a wake-up signal based on the internal clock timing, wherein the wake-up signal is used to wake up the device; Based on the wake-up signal, the signal receiving module is triggered to obtain a Bunsen echo signal, where the Bunsen echo signal is an echo signal generated by the target dangerous rock body under natural conditions. If the Bunsen echo signal is obtained, the state of the target dangerous rock body is analyzed according to the Bunsen echo signal, otherwise the method described in any one of claims 1 to 6 is triggered to execute.

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