Rock burst master control horizon determination method

Abstract

The invention provides a rock burst master control layer determination method, which comprises the following steps of: establishing a mining area stratum model, and determining a plurality of rock burst control layers in a fissure zone through a key layer theory; main control layer analysis is carried out on all the rock burst control layers in the fissure zone, a step-by-step determination and governance analysis principle is formulated for all the rock burst control layers, and a multi-stage rock burst main control layer is determined; logging correction analysis is conducted, and the position of the target rock stratum of the multi-stage rock burst main control layer is dynamically corrected. According to the method, the multi-stage rock burst main control layer is determined stage by stage, on the basis of comprehensively covering the rock burst control layer with the washout inducing risk, other rock burst control layers without the rock burst risk after the current rock burst control layer is treated are removed, blind treatment is avoided, and the control efficiency is improved. And the target rock stratum of the rock burst main rock stratum is dynamically and actively corrected through logging analysis, and the selected layer position of the target rock stratum of the rock burst main rock stratum is further corrected from the angle of construction treatment.

Description

Technical Field

[0001] This invention relates to the field of coal mining technology, and in particular to a method for determining the main stratigraphic location of rockburst. Background Technology

[0002] Coal is a crucial basic energy source in my country. Although the proportion of coal consumption in my country's total primary energy consumption has been declining in recent years, the absolute amount of coal consumption has continued to grow due to the continuous increase in total energy consumption. In areas where the main coal seams are buried at depths of approximately 600-750 meters, the high static load caused by the low-lying thick and hard roof, combined with the strong dynamic load resulting from its fracture, easily induces rockbursts. Meanwhile, the fracture of the high-lying thick and hard roof releases a large amount of elastic energy, easily leading to frequent surface seismic events. According to actual monitoring, a large number of seismic events are distributed above 200 meters in the roof, exceeding the scope of existing underground technologies for mitigation. Rockbursts and seismic events have become major challenges restricting safe coal mining in this region.

[0003] Furthermore, the prevention and control of rockbursts suffers from inaccurate target strata. Often, control measures are implemented only after the rockburst problem has occurred. Because the target strata are unclear, the main controlling strata of rockbursts cannot be reasonably determined, resulting in insignificant control effects. The only option is to expand the control area as much as possible to cover the target strata, leading to a lack of responsiveness in the control efforts. Summary of the Invention

[0004] The present invention aims to at least partially solve one of the technical problems in the related art.

[0005] To achieve the above objectives, this invention proposes a method for determining the main stratigraphic level of rockburst, comprising the following steps:

[0006] S1. Based on three-dimensional seismic exploration, borehole core, and microseismic location analysis, establish a geological model of the mining area, select the working face, and determine, through the key layer theory, all rockburst control layers within the fracture zone in the geological model of the mining area that have the risk of rockburst.

[0007] S2. Conduct a primary control layer analysis on all rockburst control layers within the fracture zone, formulate a principle of hierarchical determination and treatment analysis for all rockburst control layers, eliminate other rockburst control layers that do not pose a rockburst risk after the current rockburst control layer is treated, and determine multi-level primary rockburst control layers from all rockburst control layers.

[0008] S3. Conduct well logging correction analysis to dynamically correct the stratigraphic position of the target rock layer in the multi-level rockburst control layer.

[0009] This invention defines the key layers within the fracture zone as rockburst control layers for remediation analysis. By determining multi-level rockburst control layers at each level, it comprehensively covers rockburst control layers with the risk of induced rockbursts and eliminates other rockburst control layers that no longer pose a rockburst risk after the current rockburst control layer is remediated. This reduces the number of rockburst control layers that need to be remediated, avoiding blind remediation. Furthermore, through well logging analysis, the target rock layers of the main rockburst control layer are dynamically and actively corrected, further refining the selection of the target rock layers from the perspective of feasible remediation.

[0010] Optionally, the confirmation of rockburst control layers includes the following steps:

[0011] S11. Calculate the energy released when the critical layer fails;

[0012] S12. Analyze the measured energy of each sensor in historical rockburst cases in the current area to determine the vibration energy attenuation law;

[0013] S13. Based on the energy released by the failure of the key layer and the attenuation law of vibration energy, the remaining energy transmitted to the working face is calculated.

[0014] S14. Based on the analysis of energy accumulation, transfer, release and dissipation after mining, establish a residual energy induced impact risk assessment system, determine the induced impact conditions, and identify the rock strata whose residual energy meets the induced impact conditions as the main rock strata controlling rock pressure.

[0015] Furthermore, in S1, the calculation of the energy released by the failure of the critical layer includes calculating the elastic energy released by the initial failure of the critical layer and the elastic energy released by the periodic failure, so as to obtain the energy of the critical layer at different heights from the working surface.

[0016] Furthermore, the elastic energy released upon initial failure of the critical layer is calculated, and the elastic energy released upon initial failure of the fixed-support beam is calculated as follows:

[0017]

[0018] In the formula, U dc The elastic energy is released during the initial fracture of the basic top; q dc E is the unit length equivalent load of the self-weight of the basic top and the additional load of the overlying rock strata; d R is the elastic modulus of the beam at the basic top. t h is the tensile strength of the basic top rock layer; d b is the thickness of the basic top; dc This refers to the suspended span at the moment of the initial failure of the basic top.

[0019] Furthermore, the elastic energy released during the periodic failure of the key layer is calculated. The elastic energy released when the thick main top layer experiences periodic failure, calculated as a cantilever beam, is as follows:

[0020]

[0021] In the formula, U dz The elastic energy is released to break the fundamental top cycle; q dz b is the unit length equivalent load of the self-weight of the basic top cantilever beam model and the additional load of the overlying rock strata; dz E represents the suspended span at the point of failure of the basic top cycle. d R is the elastic modulus of the beam at the basic top. t h is the tensile strength of the basic top rock layer; d The thickness of the basic top.

[0022] Furthermore, in S12, when analyzing the measured energy of each sensor in historical rockburst cases in the current region, the following is included:

[0023] The seismic waves of the rockburst occurring at the working face are measured at multiple measuring points to form velocity-time history curves, which reflect the maximum vibration velocity of each sensor.

[0024] The displacement time history curve is obtained by integrating the velocity time history curve, which is used to reflect the positional changes of medium particles during the propagation of the vibration wave.

[0025] Furthermore, in S12, when calculating the energy transmitted to the working surface, based on the principle that the energy of the vibration wave at a certain point is proportional to the square of the maximum particle velocity at that point, the energy of the vibration wave at a certain measuring point is calculated, and an equation relating energy to the maximum particle velocity at that point is established:

[0026]

[0027] Where A0 is the maximum particle velocity at a certain point; C is the fitting coefficient; and E is the vibration wave radiation energy.

[0028] By organizing the energy calculation results of the seismic wave measuring points, the maximum vibration velocity-distance curve is obtained. The distance refers to the distance between each sensor and the seismic source. The vibration energy attenuation law is obtained from the maximum vibration velocity-distance curve.

[0029] Furthermore, in S14, when establishing the residual energy induced impulse risk determination system, the system equations are as follows:

[0030] E e +ΔE=E P +E r ;

[0031] In the formula, E eThis refers to the elastic deformation energy of the coal and rock mass before excavation.

[0032] ΔE represents the increase in deformation energy caused by mining disturbance;

[0033] E P The energy dissipated during the plastic deformation and destruction of the excavated coal and rock mass;

[0034] E r This represents the remaining energy.

[0035] Furthermore, when determining the induced impulse condition in S14, when E in the system... P <E e When +ΔE, then E r >0, at this time E r This is the energy source of the rockburst, when the remaining energy E r All of this energy is converted into the kinetic energy of the ejected coal and rock, resulting in a rockburst.

[0036] Furthermore, in S2, the principles for determining and analyzing the control of multiple rockburst control layers at different levels include:

[0037] The remaining energy of multiple rockburst control layers is compared, and the rockburst control layer with the largest remaining energy transmitted to the working face is taken as the primary rockburst control layer. The primary rockburst control layer is then analyzed for mitigation.

[0038] Repeat step S1 to assess the risk of rockbursts in other control layers adjacent to the main control layer to be treated. Eliminate rockburst control layers that no longer pose a risk of rockbursts and designate rockburst control layers that are adjacent to the main control layer to be treated and still pose a risk of induced rockbursts as the next level of main control layers to be treated.

[0039] Repeat this process until no other critical layers pose a risk of rockburst disaster, thus forming a multi-level rockburst control layer.

[0040] Furthermore, in S3, well logging analysis is performed. The target rock layer corresponding to the identified rock layer controlling the main rock pressure is observed and measured through well logging. Lithology, rock layer strength, sandstone content, and mud content are obtained to determine the fracturing capability of the target rock layer. The target rock layer position of the rock layer controlling the main rock pressure is dynamically corrected in the treatment analysis stage.

[0041] Furthermore, in performing well logging analysis in S5, the logging analysis methods include resistivity logging, sonic logging, and natural gamma logging, among which:

[0042] Resistivity logging determines lithology and fluid properties by measuring the resistivity of formations.

[0043] Sonic logging measures the propagation speed and amplitude attenuation of sound waves in the formation to estimate porosity and lithology.

[0044] Natural gamma logging detects the natural radioactivity of formations and is used to analyze lithological composition, stratigraphic boundaries, and mineral content.

[0045] Furthermore, when the target rock layer in the corresponding main control layer contains mudstone or the mud content of the rock layer is greater than the mud content requirement of fine sandstone, the target rock layer is subjected to a fracturing test. When the fracturing of the target rock layer deteriorates, the target layer is not conducive to fracturing treatment.

[0046] Based on the rock formation information obtained from well logging, the target rock formations of the main control layer are selected in order from closest to furthest from the current target layer, and then the nearest rock formation with sandstone content that meets or exceeds the standard for fine sandstone content is corrected.

[0047] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0048] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein:

[0049] Figure 1 This is a schematic diagram of the overall method steps for determining the main stratigraphic position of rockburst according to the present invention;

[0050] Figure 2 This is a detailed method step for determining the rockburst control layer in step S1 of a method for determining the main control layer of rockburst according to the present invention;

[0051] Figure 3 This is a schematic diagram of the initial fracture and induced impact of a low-lying thick hard roof slab in accordance with a method for determining the main control layer of rockburst according to the present invention.

[0052] Figure 4 This is a schematic diagram of the low-level thick hard roof rupture induced impact according to a method for determining the main control layer of rockburst according to the present invention;

[0053] Figure 5 This is a schematic diagram of the treatment analysis after determining the main rockburst control layer of a certain level according to the method for determining the main rockburst control layer of the present invention.

[0054] Figure 6 This is a schematic diagram illustrating the determination and treatment analysis of the next level of rockburst control layer after a certain level of rockburst control layer has been treated, according to a method for determining the main rockburst control layer of the present invention.

[0055] Figure 7 This is a schematic diagram of the maximum vibration velocity-distance curve corresponding to the rockburst, based on a method for determining the main control layer of rockburst according to the present invention. Detailed Implementation

[0056] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein 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 with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0057] This invention proposes a method for determining the main stratigraphic position of rockbursts, as described below. Figures 1 to 7 Please provide a detailed explanation.

[0058] A method for determining the main stratigraphic level of rockburst includes the following steps:

[0059] S1. Based on three-dimensional seismic exploration, borehole core, and microseismic location analysis, establish a geological model of the mining area, select the working face, and determine, through the key layer theory, all rockburst control layers within the fracture zone in the geological model of the mining area that have the risk of rockburst, that is, all key layers within the fracture zone in the geological model of the mining area are determined as rockburst control layers.

[0060] S2. Conduct a primary control layer analysis on all rockburst control layers within the fracture zone, formulate a principle of hierarchical determination and treatment analysis for all rockburst control layers, eliminate other rockburst control layers that do not pose a rockburst risk after the current rockburst control layer is treated, and determine multi-level primary rockburst control layers from all rockburst control layers.

[0061] S3. Conduct well logging correction analysis to dynamically correct the stratigraphic position of the target rock layer in the multi-level rockburst control layer.

[0062] This invention defines the key layers within the fracture zone as rockburst control layers for remediation analysis. By determining multi-level rockburst control layers at each level, it comprehensively covers rockburst control layers with the risk of induced rockbursts and eliminates other rockburst control layers that no longer pose a rockburst risk after the current rockburst control layer is remediated. This reduces the number of rockburst control layers that need to be remediated, avoiding blind remediation. Furthermore, through well logging analysis, the target rock layers of the main rockburst control layer are dynamically and actively corrected, further refining the selection of the target rock layers from the perspective of feasible remediation.

[0063] In some embodiments, S1 includes the following steps when confirming the rockburst control layer:

[0064] S11. Calculate the energy released when the critical layer fails;

[0065] S12. Analyze the measured energy of each sensor in historical rockburst cases in the current area to determine the vibration energy attenuation law;

[0066] S13. Based on the energy released by the failure of the key layer and the attenuation law of vibration energy, the remaining energy transmitted to the working face is calculated.

[0067] S14. Based on the analysis of energy accumulation, transfer, release and dissipation after mining, establish a residual energy induced impact risk assessment system, determine the induced impact conditions, and identify the rock strata whose residual energy meets the induced impact conditions as the main rock strata controlling rock pressure.

[0068] By analyzing the measured energy of various sensors in historical rockburst cases in the current region, the attenuation law of rockburst vibration energy is determined. Combined with the energy release during key layer failure, the main rock strata controlling the rockburst are identified. This approach integrates theoretical calculations with field monitoring, reducing the possibility of discrepancies between purely theoretical calculations and actual conditions.

[0069] In some embodiments, when a mine-induced disaster control layer exists in a key layer within the fracture zone, the mine-induced disaster control layer is regarded as a rockburst control layer. The rockburst control layer is confirmed in the same way as in step S1, and participates in the treatment analysis and step-by-step determination of the main rockburst control layer in step S2.

[0070] In some embodiments, in S1, calculating the energy released by the failure of the critical layer includes calculating the elastic energy released by the initial failure of the critical layer and the elastic energy released by periodic failure, thereby obtaining the energy of the critical layer at different heights from the working surface. (Refer to...) Figures 2 to 3 Taking a low-lying, thick, hard top plate as an example, an impact load analysis diagram of the initial fracture induced impact and periodic fracture induced impact of the key layer is presented.

[0071] In some embodiments, the elastic energy released upon initial failure of the critical layer is calculated as follows: The elastic energy released upon initial failure of a fixed-support beam is calculated as follows:

[0072]

[0073] In the formula, U dc The initial fracture of the basic top releases elastic energy;

[0074] q dc The unit length equivalent load is the self-weight of the basic top and the additional load of the overlying rock strata.

[0075] E d The elastic modulus of the beam at the basic top;

[0076] R t The tensile strength of the basic top rock layer;

[0077] h d The thickness of the basic top;

[0078] b dc This refers to the suspended span at the moment of the initial failure of the basic top.

[0079] In some embodiments, the elastic energy released by the periodic failure of the key layer is calculated, and the elastic energy released when the thick main top layer experiences periodic failure is calculated as follows, based on the cantilever beam method:

[0080]

[0081] In the formula, U dz The basic top cycle is broken to release elastic energy;

[0082] q dz The unit length equivalent load is the self-weight of the basic top cantilever beam model and the additional load of the overlying rock strata.

[0083] b dz The suspended span when the basic top cycle breaks;

[0084] E d The elastic modulus of the beam at the basic top;

[0085] R t The tensile strength of the basic top rock layer;

[0086] h d The thickness of the basic top.

[0087] In some embodiments, S12, when analyzing the measured energy of each sensor in historical rockburst cases in the current region, includes:

[0088] The seismic waves of the rockburst occurring at the working face were measured at multiple measuring points to obtain the measured waveforms. Velocity-time history curves were then generated based on these measured waveforms, reflecting the maximum vibration velocity at each sensor.

[0089] Integrating the velocity time history curve yields the displacement time history curve, as shown below. Figure 6 As shown, the displacement-time history curve is used to reflect the positional changes of medium particles during the propagation of the vibration wave;

[0090] When calculating the energy of a seismic wave at a certain measuring point, based on the principle that the energy of a seismic wave at a certain point is proportional to the square of the maximum velocity of the particle at that point, an equation relating the energy to the maximum velocity of the particle at that point is established:

[0091]

[0092] In the formula, A0 is the maximum velocity of a particle at a certain point;

[0093] C is the fitting coefficient;

[0094] E represents the energy radiated by the vibration wave;

[0095] By analyzing the energy calculation results from the seismic wave measurement points, a maximum vibration velocity-distance curve was obtained. Here, distance refers to the distance between each sensor and the seismic source. Figure 7 As shown, the vibration energy attenuation law is obtained from the maximum vibration velocity-distance curve.

[0096] In some embodiments, when establishing the residual energy induced impulse risk determination system in S14, the system equations are established as follows:

[0097] E e +ΔE=E P +E r ;

[0098] In the formula, E e This refers to the elastic deformation energy of the coal and rock mass before excavation.

[0099] ΔE represents the increase in deformation energy caused by mining disturbance;

[0100] E P The energy dissipated during the plastic deformation and destruction of the excavated coal and rock mass;

[0101] E r This represents the remaining energy.

[0102] In some embodiments, when determining the impulse-induced condition in S14, when E in the system P <E e When +ΔE, then E r >0, at this time E r This is the energy source of the rockburst, when the remaining energy E r All of this energy is converted into the kinetic energy of the ejected coal and rock, resulting in a rockburst.

[0103] In some embodiments, the principle for determining and analyzing the control of multiple rockburst control layers in S2 includes:

[0104] The remaining energy of multiple rockburst control layers is compared, and the rockburst control layer with the largest remaining energy transmitted to the working face is taken as the primary rockburst control layer. The primary rockburst control layer is then analyzed for mitigation.

[0105] Repeat step S1 to assess the risk of rockbursts in other control layers adjacent to the main control layer to be treated. Eliminate rockburst control layers that no longer pose a risk of rockbursts and designate rockburst control layers that are adjacent to the main control layer to be treated and still pose a risk of induced rockbursts as the next level of main control layers to be treated.

[0106] Repeat this process until no other critical layers pose a risk of rockburst disaster, thus forming a multi-level rockburst control layer.

[0107] More specifically, when determining the controlling layers of multi-level rockbursts:

[0108] In the geological model of the mining area, the rockburst control layer with the largest remaining energy transmitted to the working face is selected as the primary rockburst control layer, and a mitigation simulation analysis is conducted on the primary rockburst control layer.

[0109] After the primary rockburst control layer is treated, the remaining rockburst control layers on both sides above and below the primary rockburst control layer are assessed for rockburst risk. The rockburst control layers that still pose a risk of inducing rockburst are identified as the secondary rockburst control layers.

[0110] Repeat this process until the main control layer of the N-level rockburst is identified, and after the main control layer of the N-level rockburst is treated, the key layers within the two zones no longer pose a risk of inducing rockburst.

[0111] In some embodiments, in step S3, well logging analysis is performed to observe and measure the target rock layer corresponding to the determined rock layer controlling the main rock pressure in the mining and seismic activity, obtain lithology, rock layer strength, sandstone content, and mud content, determine the fracturing capability of the target rock layer, and dynamically correct the target rock layer strata position of the rock layer controlling the main rock pressure in the treatment analysis stage.

[0112] In some embodiments, when performing well logging analysis in S3, the well logging analysis methods include resistivity logging, sonic logging, and natural gamma logging, wherein...

[0113] Resistivity logging works by measuring the resistivity of the formation to determine the lithology and fluid properties.

[0114] Specific technologies include:

[0115] Lateral logging technology emits focused current into the formation, reducing the impact on the wellbore and surrounding rock, and is suitable for high resistivity formations;

[0116] Induction logging technology uses the principle of electromagnetic induction to measure formation conductivity and is suitable for wellbores with low resistivity or filled with conductive mud.

[0117] Sonic logging works on the principle of measuring the propagation speed (time difference) and amplitude attenuation of sound waves in the formation to estimate porosity and lithology. Sound waves propagate quickly in dense rocks (such as limestone and hard sandstone) and slowly in loose or porous rocks. The ratio of P-wave to S-wave velocity can also be used to assess the mechanical properties of the formation (such as fracture pressure).

[0118] Natural gamma logging works on the principle of detecting the natural radioactivity of formations (mainly from potassium, uranium, and thorium isotopes). Mudstone has high radioactivity, while sandstone and limestone have low radioactivity, which is used to analyze lithological composition, stratigraphic boundaries, and mineral content.

[0119] In some embodiments, when the target rock layer of the corresponding main control layer contains mudstone or the mud content of the rock layer is greater than the mud content requirement of fine sandstone, the target rock layer is subjected to a fracturing test. When the fracturing of the target rock layer deteriorates, the target layer is not conducive to fracturing treatment.

[0120] Based on the rock formation information obtained from well logging, the target rock formations of the main control layer are selected in order from closest to furthest from the current target layer, and then the nearest rock formation with sandstone content that meets or exceeds the standard for fine sandstone content is corrected.

[0121] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0122] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0123] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0124] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0125] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0126] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A method for determining the main stratigraphic level of rockburst, characterized in that, Includes the following steps: S1. Based on three-dimensional seismic exploration, borehole core, and microseismic location analysis, establish a geological model of the mining area, select the working face, and determine, through the key layer theory, all rockburst control layers within the fracture zone in the geological model of the mining area that have the risk of rockburst. S2. Conduct a primary control layer analysis on all rockburst control layers within the fracture zone, formulate a principle of hierarchical determination and treatment analysis for all rockburst control layers, eliminate other rockburst control layers that do not pose a rockburst risk after the current rockburst control layer is treated, and determine multi-level primary rockburst control layers from all rockburst control layers. S3. Conduct well logging correction analysis to dynamically correct the stratigraphic position of the target rock layer in the multi-level rockburst control layer.

2. The method for determining the main stratigraphic location of rockburst as described in claim 1, characterized in that, The steps involved in confirming the rockburst control layer are as follows: S11. Calculate the energy released when the critical layer fails; S12. Analyze the measured energy of each sensor in historical rockburst cases in the current area to determine the vibration energy attenuation law; S13. Based on the energy released by the failure of the key layer and the attenuation law of vibration energy, the remaining energy transmitted to the working face is calculated. S14. Based on the analysis of energy accumulation, transfer, release and dissipation after mining, establish a residual energy induced impact risk assessment system, determine the induced impact conditions, and identify the rock strata whose residual energy meets the induced impact conditions as the main rock strata controlling rock pressure.

3. The method for determining the main stratigraphic location of rockburst as described in claim 1, characterized in that, In S1, the calculation of the energy released by the failure of the critical layer includes calculating the elastic energy released by the initial failure of the critical layer and the elastic energy released by the periodic failure, so as to obtain the energy of the critical layer at different heights from the working surface.

4. The method for determining the main stratigraphic location of rockburst as described in claim 3, characterized in that, The elastic energy released at the initial failure of the critical layer is calculated as follows: (Calculate the elastic energy released at the initial failure of the beam as a fixed-support beam.) In the formula, U dc The elastic energy is released during the initial fracture of the basic top; q dc E is the unit length equivalent load of the self-weight of the basic top and the additional load of the overlying rock strata; d R is the elastic modulus of the beam at the basic top. t h is the tensile strength of the basic top rock layer; d b is the thickness of the basic top; dc This refers to the suspended span at the moment of the initial failure of the basic top.

5. The method for determining the main stratigraphic position of rockburst as described in claim 4, characterized in that, The elastic energy released during the periodic failure of the key layer is calculated as follows, based on the cantilever beam model: In the formula, U dz The elastic energy is released to break the fundamental top cycle; q dz b is the unit length equivalent load of the self-weight of the basic top cantilever beam model and the additional load of the overlying rock strata; dz E represents the suspended span at the point of failure of the basic top cycle. d R is the elastic modulus of the beam at the basic top. t h is the tensile strength of the basic top rock layer; d The thickness of the basic top.

6. The method for determining the main stratigraphic location of rockburst as described in claim 2, characterized in that, In step S12, when analyzing the measured energy of each sensor in historical rockburst cases in the current region, the following is included: The seismic waves of the rockburst occurring at the working face are measured at multiple measuring points to form velocity-time history curves, which reflect the maximum vibration velocity of each sensor. The displacement time history curve is obtained by integrating the velocity time history curve, which is used to reflect the positional changes of medium particles during the propagation of the vibration wave.

7. The method for determining the main stratigraphic position of rockburst as described in claim 6, characterized in that, In step S12, when calculating the energy transmitted to the working surface, based on the principle that the energy of the vibration wave at a certain point is proportional to the square of the maximum particle velocity at that point, the energy of the vibration wave at a certain measuring point is calculated, and an equation relating energy to the maximum particle velocity at that point is established: Where A0 is the maximum particle velocity at a certain point; C is the fitting coefficient; and E is the vibration wave radiation energy. By organizing the energy calculation results of the seismic wave measuring points, the maximum vibration velocity-distance curve is obtained. The distance refers to the distance between each sensor and the seismic source. The vibration energy attenuation law is obtained from the maximum vibration velocity-distance curve.

8. The method for determining the main stratigraphic position of rockburst as described in claim 2, characterized in that, In step S14, when establishing the residual energy induced impulse risk assessment system, the system equations are as follows: E e +ΔE=E P +E r ; In the formula, E e This refers to the elastic deformation energy of the coal and rock mass before excavation. ΔE represents the increase in deformation energy caused by mining disturbance; E P The energy dissipated during the plastic deformation and destruction of the excavated coal and rock mass; E r This represents the remaining energy.

9. The method for determining the main stratigraphic position of rockburst as described in claim 8, characterized in that, When determining the induced impulse condition in S14, when E in the system P <E e When +ΔE, then E r >0, at this time E r This is the energy source of the rockburst, when the remaining energy E r All of this energy is converted into the kinetic energy of the ejected coal and rock, resulting in a rockburst.

10. The method for determining the main stratigraphic location of rockburst as described in claim 1, characterized in that, In S2, the principles for determining and analyzing the control of multiple rockburst control layers at different levels include: The remaining energy of multiple rockburst control layers is compared, and the rockburst control layer with the largest remaining energy transmitted to the working face is taken as the primary rockburst control layer. The primary rockburst control layer is then analyzed for mitigation. Repeat step S1 to assess the risk of rockbursts in other control layers adjacent to the main control layer to be treated. Eliminate rockburst control layers that no longer pose a risk of rockbursts and designate rockburst control layers that are adjacent to the main control layer to be treated and still pose a risk of induced rockbursts as the next level of main control layers to be treated. Repeat this process until no other critical layers pose a risk of rockburst disaster, thus forming a multi-level rockburst control layer.

11. The method for determining the main stratigraphic location of rockburst as described in claim 1, characterized in that, In S3, well logging analysis is performed. The target rock layer corresponding to the identified rock layer controlling the main rock pressure is observed and measured through well logging. Lithology, rock layer strength, sandstone content, and mud content are obtained to determine the fracturing capability of the target rock layer. The target rock layer position of the rock layer controlling the main rock pressure is dynamically corrected in the treatment analysis stage.

12. The method for determining the main stratigraphic position of rockburst as described in claim 11, characterized in that, When performing well logging analysis in S3, the logging analysis methods include resistivity logging, sonic logging, and natural gamma logging, among which: Resistivity logging determines lithology and fluid properties by measuring the resistivity of formations. Sonic logging measures the propagation speed and amplitude attenuation of sound waves in the formation to estimate porosity and lithology. Natural gamma logging detects the natural radioactivity of formations and is used to analyze lithological composition, stratigraphic boundaries, and mineral content.

13. The method for determining the main stratigraphic position of rockburst as described in claim 12, characterized in that, When the target rock layer in the corresponding main control layer contains mudstone or the mud content of the rock layer is greater than the mud content requirement of fine sandstone, the target rock layer is subjected to a fracturing test. When the fracturing of the target rock layer deteriorates, the target layer is not suitable for fracturing treatment. Based on the rock formation information obtained from well logging, the target rock formations of the main control layer are selected in order from closest to furthest from the current target layer, and then the nearest rock formation with sandstone content that meets or exceeds the standard for fine sandstone content is corrected.

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