RU2535329C1 - Method for determining rock mass bump hazard by electromagnetic emission, and device for its implementation - Google Patents

Abstract

FIELD: measurement equipment.

SUBSTANCE: invention refers to mining and is meant for evaluation of stress strain behaviour of rock mass section by recording pulse emission of electromagnetic oscillations. Method involves measurement of maximum amplitudes in roadway and maximum activity of electromagnetic emission on record threshold above the level of electromagnetic emission background. In the range of amplitudes from zero reading to maximum reading, calculated is A parameter as logarithmic mean value of distribution of pulses peak amplitudes. All the values of amplitudes of the specified range are divided into 10 unequal threshold in logarithmic progression in increment divisible by log₂. Bar chart of signals distribution is built in double logarithmical coordinates. Based on this bar chart calculated is B parameter as estimation of rise rate of pulses peak amplitudes above the threshold level. Dependence diagrams of parameter values A(x_i) and B(x_i) from station x_i location on roadway profile are built as well as diagrams of gradients of these parameters functions. Critical values of Acr and Bcr are determined as well as their total critical rate of change. Rock-bump hazardous considered are those sections where at least four of three inequations are realised simultaneously. Device contains series-connected electromagnetic sensor, preamplifier and amplifier, analogue-to-digital converter and digital processing unit with indicating unit connected to it. According to the method the device is additionally provided with low-frequency filter connected to series circuit between preamplifier and amplifier, series connected between amplifier and analogue-to-digital converter, the second low-frequency filter and high-frequency filter, as well as reference voltage source, and to digital processing unit connected is quick operating digital signal processor double connected to analogue-to-digital converter, double connected also to programs non-volatile memory, data flash-memory and USB-port.

EFFECT: improving accuracy and reliability of rocks dynamic fracture forecast, as well as reducing labour intensity and improving measurements processibility.

8 cl, 5 dwg

Description

The invention relates to mining and is intended to assess the stress-strain state of a section of a rock mass in mines and mines developing formations that are dangerous for rock impacts and emissions by recording pulsed radiation of electromagnetic or elastic vibrations from fracture cracks generated under the action of ultimate stresses.

Intensive growth in mineral production leads to an increase in the depth of their development and complication of the geomechanical conditions of mining. The consequence of this is the occurrence of such dangerous situations in which the existing methods for monitoring the dynamics of changes in strength characteristics in the rock mass do not fully reflect the true picture of the processes occurring in it.

The basis for the prevention of these natural and technological phenomena are: a regional forecast, which is an assessment of the geodynamic hazard of formations within deposits and mine allotments of mines; local forecast, i.e. prediction and assessment of the stress-strain state of sections of the rock mass within the excavation fields and specific workings, usually carried out using drilling equipment for the release of drilling fines or core drilling.

At the same time, to ensure the efficiency of mining operations, the development and development of modern methods for continuous monitoring and evaluation of the stress-strain state of an array using portable instruments is of particular relevance.

Modern geophysical systems are characterized by the widespread use of computerized devices and the latest powerful computers for digital recording and processing of large amounts of information, using modern materials and products that allow measurements at great depths, as well as in extreme climatic conditions. All this allows a new approach to the process of obtaining and processing geophysical information.

As you know, the basic methods of local forecasting (impact hazard forecast for the output of a bayonet, core disking) are based on regulatory documents. The main disadvantage of the basic methods for predicting shock hazard is the obligatory drilling of wells (holes) and, as a result, their high complexity and duration of execution.

Recently, methods based on registration of natural electromagnetic emission (EEMI) are finding more and more application for solving problems of local forecasting.

The physical basis for using electromagnetic methods is the established dependence of energy, amplitude, duration, frequency, propagation velocity and other parameters of electromagnetic waves on the stress state and physical and mechanical properties of rocks.

The forecast of the impact hazard of sections of the rock massif consists in changing one or more parameters of electromagnetic waves according to methods that take into account the characteristics of each particular mine.

The Known Method of controlling the discontinuity of the rock mass according to the author's certificate of the USSR No. 1101552, IPC E21C 39/00, publ. 07/07/1984, including the registration of electromagnetic emission signals and measuring their duration, determining the average duration of pulses arising from the redistribution of rock pressure, which is taken as the reference, comparing subsequent signals with the reference, the selection of pulses with a duration of more than an order of magnitude longer than the reference, and by their appearance they judge the occurrence of stratification.

However, this method does not allow to register the amplitude of the electromagnetic emission signals, which reduces the accuracy and reliability of the information received. In addition, using this method, the number of received signals is not recorded, the presence of which also gives additional information about the process of changing the stress-strain state in the array and the approximation of the fracture process.

There is also known a Method for predicting the destruction of rocks according to the patent of the Russian Federation No. 2137920, IPC E21C 39/00, G01N 29/04, publ. 09/20/1999, including registration on a time interval of measurement of electromagnetic radiation signals and measurement of their amplitudes, which determine the beginning of the destruction of the investigated section of the array, and the measurement time interval is divided into two unequal parts, each of them measures the magnitudes of the signal amplitudes through equal the time intervals before loading the investigated section of the array determine the radiation intensity of the interference signal by measuring the amplitudes of the signals over most of the measurement time interval, and the beginning of The destruction moment is determined as the studied section of the array is loaded according to the mathematical relation.

The disadvantage of this method is that in the place of study of the site of the rock mass it is necessary to make several measurements, which greatly affects the duration and complexity of the work. In addition, to ensure the accuracy of prediction of the beginning of the rock destruction process, it is necessary to carry out measurements as the studied section of the mass is loaded, but the question of how to evaluate the loading process has not been resolved.

Closest to the proposed method in terms of technical nature and the achieved result is a method for assessing the impact and outburst hazard of the edge of the massif and the effectiveness of measures to combat them according to USSR patent No. 1717846, IPC E21F 5/00, publ. 03/07/1992, including the measurement at the bottom of the output of the maximum amplitude and activity of electromagnetic radiation (EMP) at two detection thresholds above the background level of EMP, the determination of the critical value of the activity of EMP and the assessment of the impact hazard of the edge of the formation. According to the method, the EMR detection thresholds are selected depending on the maximum and background amplitude of the pulses (AI) of the EMR. At the selected AI thresholds, stable average values of the pulses of EMR activity and critical values of the pulses of EMR activity are measured, and if the pulse exceeds the critical values of the EMR activity, the section is considered shock hazardous. Then they take measures to eliminate the shock hazard and evaluate their effectiveness. With pulses of activity of electromagnetic radiation, less than their critical values, the zone is considered non-shocking. When assessing the outburst hazard, the initial gas release rate and its critical value are additionally determined, and the zone is considered to be outburst hazardous if at the same time the EMR pulses are more critical and the initial gas evolution velocity is more than critical.

This method of assessing the impact hazard improves the safety of work by differentiating the stress state of the boundary zones of the formation and, thereby, deliberate control of its dynamic and gas-dynamic manifestations. However, in this case, only the parameters of the maximum EMP amplitudes are estimated depending on the background value of the amplitude of the EMP activity, but they do not take into account the rate of increase of peak pulse amplitudes above the threshold level, which leads to a decrease in the accuracy of prediction of rock destruction and possible outburst potential, as well as to increased labor intensity work on the implementation of shockproof measures.

In addition, the device implementing the known method is not intended for use in workings hazardous in gas and dust, because does not have the necessary spark and explosion protection.

A device for registering electromagnetic radiation arising from crack formation of rocks, according to the patent of the Russian Federation No. 1774303, IPC G01V 3/00, publ. 11/07/1992, containing a ferrite toroidal core with a winding evenly placed on it and a metal screen surrounding it. The ferrite core is made in the form of a torus, completely filled with a winding, and the screen is located in such a way that partially covers it, at an angle of 285-295 °. At the same time, on the remaining open part of the winding, a visor is additionally installed in the form of a horn with a bell outward, and the side walls of the horn form an angle of no more than 65-75 °.

The disadvantage of this device is its low sensitivity due to the inefficient use of the magnetic flux of the ferrite core, which does not allow the reception of small amplitude signals due to the weak concentration of the field in the measurement space and its high concentration in the ferrite toroidal core.

It is also known a device for recording electromagnetic radiation arising from crack formation of rocks, according to the patent of the Russian Federation No. 2155973, IPC G01M 7/02, publ. September 10, 2000, containing a ferrite toroidal core with a winding and a metal shield surrounding it. The ferrite toroidal core is made open with a solid dielectric placed in the space of its cutout with an additional winding placed on it and wound counter-winding of the ferrite toroidal core, connected in series with the winding of the ferrite toroidal core. The step of the additional winding is variable, smaller to the edges, and the ratio of the part of the additional winding with a large step to its parts with a smaller step is within certain limits, depending on the ratio of the angle counted from the horizontal axis of the cut to the start of the additional winding with a smaller step and the angle counted from the beginning of the additional winding with a smaller pitch to the ends of the core.

This device allows you to increase the sensitivity of the device due to the concentration of the field in the measurement space and can be used both to control the destruction of sections of the rock mass when changing their stress-strain state, and in laboratory conditions for recording electromagnetic radiation (EMP) arising from the destruction of samples rocks. However, the results obtained to a large extent depend on the level of electromagnetic interference, since in this device there is no system for their selection. The algorithm for rejecting false registrations is also absent. This leads to the issuance of false alarms or to the omission of a dangerous situation, which reduces the reliability and accuracy of the forecast of shock hazard of rocks.

The closest in technical essence and the achieved result to the declared one is a device for determining the degree of shock and outburst hazard of rocks according to the patent of the Russian Federation No. 2071563, IPC E21C 39/00, publ. 01/10/1997, containing a series-connected acoustic or electromagnetic emission sensor, a preamplifier, attenuator, amplifier and peak amplitude meter, as well as a pulse shaper and an indication unit. In addition, the device is equipped with an energy meter, a switch, an analog-to-digital converter and a microprocessor unit, respectively connected.

The use of this device allows to increase the efficiency of forecasting and dividing sites into hazardous, non-hazardous and especially dangerous by introducing a double gradation of the criterion of the limiting activity of electromagnetic emission, which reduces the amount and cost of measures to bring the site into a non-hazardous state.

At the same time, the disadvantages of this device are the low accuracy and reliability of the measurement results due to the presence of an error in hazard assessments due to the absence of detuning from the background radiation level and rejection of stationary signals recorded from operating mechanisms.

In addition, the disadvantage of this device is the low degree of protection of the housing from dust, moisture and gas, typical for use in mine conditions.

The invention solves the problem of increasing the reliability of determining the stress-strain state of a rock mass in a mine environment by receiving the device and subsequent analysis of signals from sources of electromagnetic waves caused by the destruction of rocks in the mass.

The technical result consists in increasing the accuracy and reliability of the forecast of dynamic destruction of rocks, as well as reducing the complexity and technological effectiveness of measurements, due, in particular, to the possibility of receiving electromagnetic emission signals only using an antenna, without contact with the array.

To achieve a technical result using the method of determining the shock hazard of a rock mass, based on the calculation of the activity of electromagnetic radiation signals and measuring the peak values of these signals for a fixed time interval at several amplitude levels, according to the invention, the bullet reference amplitude is taken into account background radiation, then from zero to the maximum, all values of the amplitudes are divided into 10 unequal thresholds in a logarithmic progression with a step that is a multiple of log ₂ , and according to the sample the peak amplitudes of the pulses are estimated by the parameters “A” and “B”, while the parameter “A” is taken as the logarithmic average of the distribution of the peak amplitudes of the pulses, and the parameter “B” is the estimated rate of rise of the peak amplitudes of the pulses above the threshold level by 10 thresholds. Then, we plot the dependences of the values of the parameters A (x _i ) and B (x _i ) on the position of the observation point x _i on the production profile, as well as the graphs of the gradients of the functions of these parameters, establish the critical values of the parameters Ac and Bcr and their total critical rate of change, and shock areas are those sections in which at least three of the four mathematical relationships obtained empirically are simultaneously satisfied.

In addition, conditionally shock hazardous, requiring additional research, are considered areas where four inequalities are simultaneously satisfied, also obtained empirically.

In this case, measurements are made on a plurality of observation points along the profile of the controlled mine, and parameter B is calculated using linear regression of the histogram values at the observation points along the profile of the controlled mine.

To implement the method, a device containing a serially connected electromagnetic radiation sensor (EMP), a preamplifier and an amplifier, as well as an analog-to-digital converter (ADC) and a digital processing unit with an indication unit connected to it, according to the invention is additionally equipped with a low-pass filter included in series the circuit between the preamplifier and the amplifier, connected in series between the amplifier and the ADC, a second low-pass filter and a high-pass filter, as well as a reference voltage source In the digital processing unit, a high-speed digital signal processor is included, connected by two-way communication to the ADC, also connected by two-way communication with non-volatile program memory, data flash memory and USB port.

In addition, in the device, the electromagnetic radiation sensor (EMP) is made in the form of an LC circuit, the ADC is multi-bit and high speed, and the series-connected LC circuit, preamplifier and low-pass filter form a receiving electromagnetic antenna, which is structurally made in the form of a cylinder made of radio-transparent material, one end of which is flooded with a compound, and the antenna cable is fixed in the other with a hermetic lead, and it is located in the slit screen.

The invention is illustrated by drawings, where figure 1 presents a histogram of the distribution of signals with an amplitude exceeding the threshold A ₀ background radiation; figure 2 - arrangement of observation points along the profile of the controlled output; figure 3 - graphs of the change of parameter A (peak amplitudes of the pulses of the EMP) and its gradient along the location of the observation points; figure 4 - graphs of the variation of parameter B (slew rate of peak amplitudes of pulses above the threshold level) and its gradient along the profile of the controlled output; figure 5 shows a structural diagram of a device that implements the method.

The claimed method is as follows.

In the rock mass in the studied area of the massif at the measurement time interval (for example, for 10 seconds), at a number of observation points along the profile of the controlled generation, electromagnetic signals are recorded and their amplitudes are measured, after which the number of amplitudes exceeding zero is calculated a threshold, and a zero reading of the amplitude A _{0 is} taken taking into account the background radiation, thereby excluding the component of “small” signals from the calculation. It was experimentally established that the range of amplitudes that are subjected to further processing should be started from a zero threshold with amplitude A ₀ , in which the number of pulses exceeds approximately 65,000, and ends with a maximum amplitude A _max recorded in a 10-second sample.

All signals with an amplitude of A ₀ and below are discarded, as they are not informative.

Among the remaining signals, the parameter A is calculated - the logarithmic average of the distribution of peak pulse amplitudes according to the formula:

where A _i are the amplitudes of individual signals. A _i > A ₀ .

Further, the entire array of signals with an amplitude of more than A _{0 is} divided into 10 unequal thresholds in a logarithmic progression in increments of a multiple of log ₂ in the range from A ₀ to A _max , where A _max is the amplitude of the maximum signal. Thus, the thresholds are "floating." This allows even with a high level of stationary interference to emit pulsed signals coming from a rock mass.

Based on the results of this division, a histogram of the distribution of signals in double logarithmic coordinates is constructed, where the logarithms of the amplitudes are plotted along the abscissa axis, and the logarithms of the quantities of signals shown in figure 1 along the ordinate axis. Based on this histogram, the parameter B is calculated using linear regression — the angle of the histogram, which essentially characterizes the estimate of the rate of rise of the peak pulse amplitudes above the threshold level.

After taking measurements at all observation points along the profile of the controlled mine, graphs of the dependences of the values of A (x _i ) and B (x _i ) on the position of the point x _i on the mine profile, as well as graphs of the gradients of the functions (A (x _i ) -A (x _i-1 )) / (x _i -x _i-1 ) and (B (x _i ) -B (x _i-1 )) / (x _i -x _i-1 ) from x _i, respectively. Examples of graphing the variation of parameter A and its gradient are shown in FIG. 2. Moreover, as can be seen in the graph, the gradient shows an increase in the rate of change in the amplitude of the signals near the studied place of the controlled output.

Similarly, graphs are constructed for parameter B and its gradient (Fig. 3), and in this case, the gradient also shows the rate of change of the distribution of signal amplitudes near the studied location of the controlled output.

The choice and calculation of not only the values of the parameters A and B themselves, but also their gradients is due to the need to monitor not only the areas of active electromagnetic emission, but also the areas of sharp increase in emission even in relatively quiet places according to dynamic phenomena. A sharp increase in the emission amplitude (increase in parameter A) or a change in the distribution of signal amplitudes can indicate a crack growth. A change in the distribution (a decrease in parameter B) may indicate a developing transition to the next stage of fracture — the massive emergence of microcracks of the next hierarchical level.

In the presence of critical values of Acr and Bcr (known from previous studies in this mine or mine) and the total critical rate of change of parameters, defined as {[dA / dx] * [dB / dx]} cr obtained by comparing measurements with one of the basic methods (for example, according to the output of a bayonet, disking of cores), those sections (x _i-1 , x _{i + 1} ), in which at least three of the four inequalities are simultaneously fulfilled, are considered to be shock hazardous:

where A (x _i ) and B (x _i ) are the values of the parameters A and B at the observation point x _i ;

Acr and Bcr are critical values of parameters A and B;

A (x _i-1 ) and B (x _i-1 ) are the values of the parameters A and B at the previous observation point with respect to the point x _i ;

A (x _{i + 1} ) and B (x _{i + 1} ) are the values of the parameters A and B at the subsequent observation point with respect to the point x _i ;

{[dA / dx] * [dB / dx]} cr - values of the total critical rate of change of parameters A and B at neighboring observation points.

At the same time, it is taken into account that the critical value of the rate of change of the parameters {[dA / dx] * [dB / dx]} cr is a negative value.

The choice of three inequalities out of four is based on the experience of measurements and means that the following situations are included in the number of shock hazardous ones:

- the critical values of Acre and Bcr are exceeded, and at the same time, this point on the mine profile is more dangerous than at least one of the two neighboring ones (thereby eliminating the “quietest” points in the shock-hazardous zone, which are not centers of intense deformation or fracture processes) ;

- at least one of the critical values (Acr or Bcr) is exceeded, but at the same time, this point on the profile is more dangerous than two neighboring ones and can become a source of intense irreversible deformation or fracture.

In the absence of accumulated critical values (for example, during the first study of a given development), conditionally shock hazardous, in which shock hazard testing by repeated measurements or measurements by other methods is necessary, are considered areas ((x _i-1 , x _{i + 1} ), on which the inequalities are simultaneously satisfied :

where A (x _i ) and B (x _i ) are the values of the parameters A and B at the observation point x _i ;

A (x _i-1 ) and B (x _i-1 ) are the values of the parameters A and B at the previous observation point with respect to the point x _i ;

A (x _{i + 1} ) and B (x _{i + 1} ) are the values of the parameters A and B at the subsequent observation point with respect to the point x _i .

The choice of all four inequalities in this case is due to the fact that the comparison is made not with critical values, but with the values of the parameters at neighboring points, and those parts that are both in absolute values of parameters A and B, and in gradients A and B show greater emission activity than neighboring ones. Even if the absolute levels of parameters A and B and their gradients are relatively small, this combination indicates a high probability of the development of irreversible processes of deformation and fracture in the array.

Thus, the developed method, unlike the existing ones, makes it possible to identify hazardous areas both by the absolute value of the amplitudes of the pulses or by the slope of the repeatability graph, and by the nature of the changes in the amplitudes themselves and their distribution. This method is applicable both in the case when the critical values of parameters A and B are known for a given rock mass, and when measuring under new conditions.

A device for recording electromagnetic radiation (Fig. 5) consists of a registration unit 1, a receiving electromagnetic antenna 2, a charger 3 and a set of cables (antenna cable 4, interface cable 5).

The registration unit 1 is placed in a standard rectangular metal case, made in a particularly explosion-proof design with a type of explosion protection, including intrinsically safe electrical circuits, for example, according to GOST R 51330-10. This type of explosion protection is achieved by limiting the parameters of electrical circuits to intrinsically safe values, for example, in the design of the power supply available in the registration unit 1, a rechargeable battery with parameters U ₀ = 9 V, I ₀ = 1.3 A, R _ogr = 66 Ohms ( flooded with compound), SQR = 10 W, 2 × 3.3 Ohms.

The registration unit 1 contains a power supply 6, an analog unit 7 and a digital processing unit 8. The analog processing unit 7 includes a series-connected amplifier 9, a low-pass filter 10, a high-pass filter 11, an analog-to-digital converter (ADC) 12 and a reference voltage source 13, which generates a temperature-stable, low noise bias voltage for operation analog units of the device in a system with unipolar power supply, the outputs of which are connected to the inputs of the receiving electromagnetic antenna 2, low-pass filter 10, high-pass filter 11 and ADC 12. In this case, ADC 12 must be multi-discharge and high speed, which will allow continuous recording of the signal in a wide dynamic range and a wide frequency spectrum.

Block 9 digital processing is a microprocessor block, built on the basis of a standard set of functional units, and includes a high-speed digital signal processor 14 connected by two-way communication to the ADC 12, also connected by two-way communication with non-volatile program memory 15, data flash memory 16 and USB port 17. The processor 14 is also connected to an indicator 18 having, for example, a liquid crystal display that provides information output in two lines of 16 characters and is located on the front panel triplets. Management of the operating modes of the device is carried out using the functional keyboard 19.

Functionally, the digital processing unit 9 is intended for receiving and transmitting information to the device blocks via standard ports of the signal processor 14, controlling the operation of the indicator 18, the keyboard 19 and other device nodes, providing an interactive dialogue with the operator at the stage of entering the initial parameters and outputting the results to a PC and t .d.

The receiving electromagnetic antenna 2 contains a series-connected LC circuit 20, a preamplifier 21 and a low-pass filter 22. Structurally, the receiving pin electromagnetic antenna 2 is made in the form of a cylinder made of radio-transparent material, one end of which is filled with a compound, and the antenna cable 4 is fixed in the other with a hermetic lead, and placed in the slotted screen 23, designed to create a directed reception of electromagnetic radiation.

The device operates as follows. The magnetic component of the EMR induces EMF in the circuit of the antenna 2, and the electrical component is cut off by the slit screen 23. The inductance of the circuit, the input capacitance, and the resistance of the preamplifier 21 determine the nature of the amplitude-frequency characteristics (AFC) of the antenna. The signal from the circuit 20 is amplified by the preamplifier 21 in terms of voltage and current, and through the low-pass filter 22 is supplied to the analog processing unit 7. In this case, the pulsed component of unsteady signals due to the natural radiation of rocks is released.

The amplified and filtered signal through a shielded antenna cable 4 enters the registration unit 1. There it is further amplified by voltage using an amplifier 9 and filtered at low and high frequencies using a low-pass filter 10 and a high-pass filter 11, respectively. The signal thus prepared is fed to a 16-bit ADC 12 and digitized at a frequency of 500 kHz. Digital samples of the signal via the serial interface (via the interface cable 5) are sent to the signal processor 14, where, depending on the selected operating mode, they are processed using special software in real time to determine the parameters “A” and “B” or written to flash memory 16 device data for subsequent cameral processing. Information about the index (picket) and the measurement result is displayed on the indicator 18. The measurement results are transferred to the personal computer (PC) from the registration unit 1 using the PC OS file manager, while the device must be turned on and connected via the USB port 17 s using interface cable 5 with a USB port on a PC (this output is not shown in the drawing).

Data is copied from the device’s memory to a computer and formatted as tabular files for subsequent textual or graphical documentation.

The measurement results are also displayed on the indicator indicator 18 of the device, where the measurement number and indicators of the radiation structure “A” and “B” are indicated, where “A” is the logarithmic average of the distribution of peak amplitudes of the pulses recorded in a given period of time (in particular, for 10; 20; 40; 80 sec); “B” is the indicator of the distribution of the amplitudes of pulses at 10 levels (tg of the slope of the direct distribution). The parameter "A" is calculated in the selected recording interval as the arithmetic average of the absolute (rectified) values of the samples or their squares, and then, taking into account the gain, are converted to microvolts.

The device as a whole can operate at an ambient temperature of -40 ° C to + 50 ° C and a relative humidity of 98 ± 2% at a temperature of 35 ± 2 ° C.

Thus, the design of the device allows it to be small-sized and consuming a small amount of electricity, provides it with a maximum degree of spark protection and makes it possible to work in conditions of strong industrial interference. Carrying and servicing the device is provided by one operator. In addition, the device provides a complete recording of the electromagnetic signal, which allows you to get the additional opportunity to allocate stationary interference.

At the same time, the application of the developed methodology for processing the received EMR signals allows to improve the quality of the forecast in the mine workings, which are characterized by an increased level of industrial interference, by increasing the accuracy and reliability of the data obtained, as well as reduce the complexity and technological effectiveness of monitoring the condition of rocks, due to the possibility of receiving signals using an antenna without contact with the array, unlike other known methods.

Claims (8)

1. A method for determining the shock hazard of a rock mass by electromagnetic emission, including measuring the maximum amplitude and activity of electromagnetic radiation (EMP) at the detection thresholds above the background level of EMP, determining the critical magnitude of the activity of EMP and assessing the impact hazard of the controlled generation, the EMR detection thresholds being selected in depending on the maximum and background amplitudes of the EMP pulses, characterized in that the threshold level of background radiation is taken as a zero reading of the EMP amplitudes, amplitude range from zero reading to the maximum calculated parameter A as the logarithmic average of the distribution of peak amplitudes of the pulses, then all the values of the amplitudes of said range divided into 10 unequal thresholds in logarithmic progression with a pitch multiple of log _2, a histogram distribution of the signals in double logarithmic scale, based on of this histogram, parameter B is calculated as an estimate of the rate of rise of the peak amplitudes of the pulses above the threshold level, graphs of the dependences of the vapor values are constructed meters A (x _i ) and B (x _i ) from the position of the observation point x _i on the production profile, as well as graphs of the gradients of the functions of these parameters, establish the critical values of the parameters Acr and Bcr and their total critical rate of change, and consider those areas that are shock hazardous, in which at least three of the four inequalities are simultaneously satisfied:
A (x _i )> Acr,
B (x _i ) <Bcr,
[(A (x _i ) -A (x _i-1 )) / (x _i -x _i-1 )] * [(B (x _i ) -B (x _i-1 )) / (x _i -x _i-1 )] <{[dA / dx] * [dB / dx]} cr,
[(A (x _{i + 1} ) -A (x _i )) / (x _{i + 1} -x _i )] * [(B (x _{i + 1} ) -B (x _i )) / (x _{i + 1} -x _i )] <{[dA / dx] * [dB / dx]} cr,
where A (x _i ) and B (x _i ) are the values of the parameters A and B at the observation point x _i ;
Acr and Bcr are critical values of parameters A and B;
A (x _i-1 ) and B (x _i-1 ) are the values of the parameters A and B at the previous observation point with respect to the point x _i ;
A (x _{i + 1} ) and B (x _{i + 1} ) are the values of the parameters A and B at the subsequent observation point with respect to the point x _i ;
{[dA / dx] * [dB / dx]} cr - values of the total critical rate of change of parameters A and B at neighboring observation points. 2. The method according to claim 1, characterized in that conditionally shock hazardous, requiring additional research, are considered areas where inequalities are simultaneously satisfied:
(A (x _i ) -A (x _i-1 ) * (B (x _i ) -B (x _i-1 )) / (x _i -x _i-1 ) <0
(A (x _{i + 1} ) -A (x _i )) * (B (x _{i + 1} ) -B (x _i )) <0
A (x _i )> min (A (x _i-1 ), A (x _{i + 1} ))
B (x _i ) <max (B (x _i-1 ), B (x _{i + 1} ))
where A (x _i ) and B (x _i ) are the values of the parameters A and B at the observation point x _i ;
A (x _i-1 ) and B (x _i-1 ) are the values of the parameters A and B at the previous observation point with respect to the point x _i ;
A (x _{i + 1} ) and B (x _{i + 1} ) are the values of the parameters A and B at the subsequent observation point with respect to the point x _i . 3. The method according to claim 1, characterized in that the measurements are made at the set of observation points along the profile of the controlled output. 4. The method according to claim 1, characterized in that the parameter B is calculated using linear regression of the histogram values at the observation points along the profile of the controlled output. 5. A device for determining the shock hazard of a rock mass by electromagnetic emission, comprising a series-connected electromagnetic radiation sensor (EMP), a preamplifier and an amplifier, as well as an analog-to-digital converter (ADC) and a digital processing unit with an indication unit connected to it, characterized in that it is additionally equipped with a low-pass filter included in the serial circuit between the preamplifier and amplifier, connected in series between the amplifier and the ADC with a second low-pass filter t and a high-pass filter, as well as a reference voltage source, the outputs of which are connected to the inputs of an EMR sensor, a second low-pass filter, a high-pass filter and an ADC, and the digital processing unit is made in the form of a microprocessor unit including a high-speed digital signal processor connected by two-way communication to the ADC, also connected by two-way communication with non-volatile program memory, data flash memory and USB port. 6. The device according to claim 5, characterized in that the electromagnetic radiation sensor (EMP) is made in the form of an LC circuit. 7. The device according to claim 5, characterized in that the ADC is multi-bit and high speed. 8. The device according to claim 5, characterized in that the LC-circuit, preamplifier and low-pass filter connected in series form a receiving electromagnetic antenna, which is structurally made in the form of a cylinder of radiolucent material, one end of which is filled with a compound, and an antenna cable is fixed in the other with a pressure seal , and placed in the slotted screen.

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