Mine earthquake and rock burst hybrid power disaster discrimination method and system

Abstract

The invention relates to a mine earthquake and rock burst hybrid dynamic disaster discrimination method and system, and the method comprises the steps: carrying out the numerical simulation of overlying strata motion evolution and stress field evolution according to geological data, and obtaining an analogue simulation result; according to the analogue simulation result, establishing a mechanical model in which the island coal pillar and the target rock stratum are simultaneously subjected to uniformly distributed load and horizontally concentrated stress; deducing an expression of dynamic and static load stress caused by fracture instability of the target rock stratum according to the mechanical model; and constructing a discriminant of the mine earthquake and rock burst composite dynamic disaster according to the dynamic and static load stress expression by combining a dynamic and static load superposition theory so as to reveal the occurrence mechanism of the mine earthquake and rock burst composite dynamic disaster of the extremely thick hard rock downhill coal pillar, and predicting the occurrence of the mine earthquake and rock burst composite dynamic disaster according to the discriminant.

Description

Technical Field

[0001] The present application relates to the field of coal mining technology, and in particular to a method and system for distinguishing a combined dynamic disaster of mine earthquake and rock burst. Background Art

[0002] Currently, coal mining primarily occurs deep within the strata. As coal seam thickness increases, geostress increases, leading to complex and variable mining geological conditions and increasingly complex mechanisms for dynamic disasters. Compound dynamic disasters, triggered by dynamic factors such as seismic activity, impact effects, and coal seam support failure, are a frequent occurrence. These disasters are primarily characterized by the interaction of seismic activity and impact effects, leading to coal pillar instability, support structure damage, and roadway deformation.

[0003] Existing technologies have relatively little research on combined dynamic disasters of rock burst and mining earthquakes and are still in their infancy, making it impossible to predict and avoid the occurrence of large-scale dynamic disasters. Summary of the Invention

[0004] In order to provide theoretical guidance and prediction methods for the prevention and control of combined dynamic disasters of mine earthquakes and impacts in coal mining, and to avoid the occurrence of large-scale dynamic disasters, the present application provides a method for distinguishing combined dynamic disasters of mine earthquakes and impact ground pressure, including: numerically simulating the overburden movement evolution and stress field evolution based on geological data to obtain simulation results; based on the simulation results, establishing a mechanical model in which the isolated coal pillar and the target rock layer are simultaneously subjected to uniformly distributed loads and horizontal concentrated stresses; based on the mechanical model, deriving the dynamic and static load stress expressions caused by the fracture and instability of the target rock layer; based on the dynamic and static load stress expressions, combined with the dynamic and static load superposition theory, constructing a discriminant for the combined dynamic disasters of mine earthquakes and impact ground pressure; and predicting the occurrence of combined dynamic disasters of mine earthquakes and impact ground pressure based on the discriminant.

[0005] Preferably, the numerical simulation of the overburden movement evolution and stress field evolution based on geological data includes: simulating the movement of the overburden during advancement along the working face through UDEC to obtain the overburden limit fracture step; simulating the mining process of the working face along the coal pillar through FLAC3D, and when the working face is pushed to the limit fracture step, the overburden deflection exceeds the critical value.

[0006] Preferably, establishing a mechanical model in which the isolated coal pillar and the target rock formation are simultaneously subjected to uniformly distributed loads and horizontal concentrated stresses includes:

[0007] The isolated coal pillar is simplified into a beam fixed with supports at both ends. The maximum tensile stress and mechanical fracture condition of the target rock formation when the rock beam is broken are obtained through the mechanical mechanism of rock beam fracture, combined with elastic mechanics and material mechanics. According to the source of horizontal stress during the mining process, the expression of horizontal concentrated stress on the target rock formation is obtained. The influence of uniformly distributed load and horizontal concentrated stress on the fracture of the isolated coal pillar is analyzed, and the fracture span of the target rock formation under the action of horizontal concentrated stress is obtained through mechanical model combined with material mechanics calculation.

[0008] Preferably, the derivation of dynamic and static load stress expressions caused by the fracture and instability of the target rock formation includes: deriving the ultimate span expression of the target rock formation through the reciprocity theorem of work, as well as the dynamic load expression and static load expression generated by the mine earthquake on the working face during fracture.

[0009] Preferably, the isolated coal pillar is split as an indeterminate beam into a superposition of a first statically determinate beam and a second statically determinate beam, and a first model of the target rock formation when it is initially fractured and a second model of the target rock formation when it is periodically fractured are constructed;

[0010] Among them, for the first model, the stress distribution of the target rock formation is solved: the stress components of the first statically determinate beam are obtained through elastic mechanics calculation; the stress components of the second statically determinate beam are obtained through the bending moment of the rectangular beam and elastic mechanics calculation; based on the stress components of the first statically determinate beam and the stress components of the second statically determinate beam, the stress components of the clamped beams at both ends of the isolated coal pillar under uniformly distributed load are calculated;

[0011] For the second model, the stress distribution of the target rock formation is solved: the stress components of the first statically determinate beam are obtained by elastic mechanics calculation; the stress components of the second statically determinate beam are obtained by semi-inverse solution and elastic mechanics calculation; based on the stress components of the first statically determinate beam and the stress components of the second statically determinate beam, the stress components of the fixed-support beams at both ends of the isolated coal pillar under uniformly distributed load are calculated.

[0012] Preferably, the fracture condition of the isolated coal pillar is judged according to the stress components before the initial fracture and the periodic fracture of the isolated coal pillar and the strength theory under complex stress state. For the target rock formation, the fracture mechanical conditions of the target rock formation of the isolated coal pillar in the absence of horizontal stress are obtained according to the maximum tensile stress criterion.

[0013] Preferably, the expression of horizontal concentrated stress on the target rock formation is obtained based on the source of horizontal stress during the mining process, including: after the solid coal on both sides of the isolated coal pillar is mined, the horizontal stress of the adjacent working faces is transferred to the horizontal stress on the isolated working face according to a triangular distribution, and the average stress increment on the isolated working face is obtained; based on the average stress increment, the change in horizontal stress on the working face of the isolated coal pillar is obtained, and the horizontal stress of the isolated coal pillar is obtained; when the working face is mined, a height direction horizontal stress transfer model is established; based on the horizontal stress transfer model, the horizontal stress transfer law along the height direction is obtained; based on the horizontal stress transfer law, the horizontal concentrated stress of the target rock formation on the isolated coal pillar is obtained.

[0014] Preferably, the expressions of dynamic and static load stress include: dynamic load stress is the strain energy stored in the rock mass when the target rock layer bends and deforms under the action of its own weight and overlying load, and the strain energy is calculated according to the reciprocity theorem of work; the dynamic load generated by the working surface after receiving the attenuated energy is obtained according to the attenuation function of energy in the process of propagating to the working face; the dynamic load stress generated by the mine earthquake on the working face when the target rock layer is fractured is obtained; the static load stress generated on the working face is obtained by superposition of the supporting rock layer below the target rock layer and the cantilever rock layer on one side.

[0015] Preferably, when the dynamic load stress generated by the mine earthquake and the static load stress in the coal body are superimposed and are greater than the critical support strength when impact mine pressure occurs, a compound dynamic disaster is triggered. Based on the calculated dynamic load stress and static load stress, a discriminant formula for the dynamic disaster caused by the combination of mine earthquake and impact ground pressure under the action of horizontal concentrated stress is obtained.

[0016] On the other hand, the present application provides a system for distinguishing the combined dynamic disasters of mine earthquake and rock burst, using any of the above methods, including: a simulation module, configured to perform numerical simulation of the overburden movement evolution and stress field evolution based on geological data to obtain simulation results; a mechanical modeling module, configured to establish a mechanical model of the isolated coal pillar and the target rock layer subjected to uniformly distributed load and horizontal concentrated stress at the same time based on the simulation results; a stress expression derivation module, configured to derive the dynamic load stress and static load stress expressions generated during the fracture and instability of the target rock layer based on the mechanical model; a disaster distinguishing module, configured to combine the dynamic and static load stress expressions based on the dynamic and static load superposition theory to form a discriminant for the combined dynamic disaster of mine earthquake and rock burst, and use it for disaster distinguishing.

[0017] It should be understood that the foregoing general description and the following detailed description are merely illustrative and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without any creative work.

[0019] Figure 1 This is a plan layout diagram of the downhill coal pillars in the 21st mining area provided in an embodiment of the present application;

[0020] Figure 2 This is a schematic diagram of the distribution of thick and hard rock formations in the downhill coal pillar area of ​​Mining Area 21 provided in one embodiment of the present application;

[0021] Figure 3 This is a schematic diagram of stress evolution during the fracture of extremely thick hard rock along the working face provided by one embodiment of the present application;

[0022] Figure 4 This is a schematic diagram of the UDEC numerical model provided in one embodiment of the present application;

[0023] Figure 5 This is a cloud diagram of vertical displacement of overburden during advancement along the strike of the working face provided by one embodiment of the present application;

[0024] Figure 6 This is a schematic diagram of a FLAC3D model provided in one embodiment of the present application;

[0025] Figure 7 is an initial geostress distribution diagram provided by an embodiment of the present application;

[0026] Figure 8 This is a schematic diagram of a plane model of thick hard rock along the downhill coal pillar provided by an embodiment of the present application;

[0027] Figure 9 This is a decomposition diagram of the initial fracture mechanics model of a thick hard rock layer provided by an embodiment of the present application;

[0028] Figure 10 This is a decomposition diagram of a periodic fracture mechanics model for thick hard rock layers provided in one embodiment of the present application;

[0029] Figure 11 This is a schematic diagram of horizontal stress transfer provided by an embodiment of the present application;

[0030] Figure 12 This is a schematic diagram of horizontal stress transfer in the height direction provided by an embodiment of the present application;

[0031] Figure 13 This is a schematic diagram of a clamped beam model under horizontal force provided by an embodiment of the present application;

[0032] Figure 14 This is a schematic diagram of dynamic and static loads during the fracture of extremely thick hard rock provided by an embodiment of the present application;

[0033] Figure 15 This is a schematic diagram of a mine earthquake occurring in a thick hard rock fracture according to an embodiment of the present application;

[0034] Figure 16 This is a schematic diagram of the mechanism of rock burst induced by the superposition of dynamic and static loads provided in one embodiment of the present application;

[0035] Figure 17 It is a schematic diagram of the structure of a system for distinguishing a combined dynamic disaster of mine earthquake and rock burst provided in one embodiment of the present application. DETAILED DESCRIPTION

[0036] The following describes in detail embodiments of the present application, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0037] According to one embodiment of the present application, a method for distinguishing a combined dynamic disaster of mine earthquake and rock burst is provided, comprising the following steps:

[0038] S01: Conduct geomechanical numerical simulation analysis; obtain three-dimensional geological data of the area to be tested, including data on coal seam occurrence, geometric dimensions of isolated coal pillars, roof and floor thickness, physical properties, and fault structure distribution. Use numerical simulation software to simulate the overburden movement evolution process during the mining process, and at the same time simulate its stress field evolution trend. Output the stress distribution and rock displacement results at different mining stages and different spatial positions to obtain simulation results.

[0039] S02: Establish a mechanical model for the isolated coal pillar region. Based on the simulation results obtained in step S01, a two-dimensional or three-dimensional mechanical model of the isolated coal pillar and the critical strata above it is constructed, subject to both uniformly distributed vertical loads and horizontal concentrated stresses. This model is used to reveal the stability characteristics of the target rock formation.

[0040] S03: Derive stress expressions under the coupled effects of static and dynamic loads. Based on the established mechanical model, combined with elastic mechanics and rock fracture theory, derive stress expressions for the dynamic and static loads to which the target rock formation is subjected under fracture and instability conditions. The static load is mainly composed of the gravity of the overlying rock formation and concentrated stress, while the dynamic load simulates the disturbance load induced by nearby mine earthquakes, sudden coal seam failure, etc.

[0041] S04: Construct a discriminant for compound dynamic disasters. Based on the dynamic and static load stress expressions derived in S03, we further introduce the theory of dynamic and static load superposition to define a critical stress discriminant to determine the potential for compound dynamic disasters. This discriminant is used to assess whether the combined effects of mine tremors and rock burst will occur under specific working conditions.

[0042] S05: Perform disaster risk prediction. Apply the discriminant constructed in S04 to different stope locations in the simulation scenario, input the current stress state and dynamic load data (which can be obtained from the microseismic monitoring system), and determine whether the corresponding area meets the disaster triggering conditions. This will then complete the spatial distribution prediction of the combined dynamic disaster of mine earthquakes and rock bursts. Simultaneously, the GIS spatial visualization system can be used to provide early warning and annotation of dangerous areas.

[0043] Through the above steps, this method can realize the disaster identification and prediction of isolated coal pillar areas under complex stress conditions, and effectively assist mine safety production.

[0044] According to one embodiment of the present application, another method for distinguishing a combined dynamic disaster of mine earthquake and rock burst is provided, comprising the following steps:

[0045] S1: Numerical simulations of the overburden movement and stress field evolution were performed based on geological data to obtain simulation results. UDEC was used to simulate the movement of the overburden as the working face advanced along its strike, and the ultimate fracture step of the overburden was obtained. FLAC3D was used to simulate the mining process along the strike of the coal pillar. When the working face reached the ultimate fracture step, the overburden deflection exceeded the critical value.

[0046] According to the above geological data, the mine project of this application involves the calculation and arrangement of three working faces of the downhill coal pillar in the 21 mining area of ​​Changcun Coal Mine. The first mining working face is the 21010 working face. The plane layout is as follows: Figure 1 As shown in the figure; Among them, the distribution diagram of the thick and hard rock layer in the downhill coal pillar area of ​​21 mining area of ​​Changcun Coal Mine is shown in the figure. Figure 2 shown.

[0047] As can be understood, since overburden movement is a change between discrete blocks, the discrete element method (DEM) simulation software UDEC was used for simulation. The stress field evolution was analyzed using the continuum mechanics analysis software FLAC3D. The model design was based on data provided by the project site. The downhill coal pillar in Mining Area 21 was modeled, using UDEC to simulate overburden movement and FLAC3D to simulate stress field evolution.

[0048] The detailed stress evolution diagram is shown in Figure 3As shown, during the mining process, stress concentration occurs in the working face, creating a stress-increasing zone. As the working face moves away from the working face, stress decreases to the in-situ stress. During the delamination phase, the collapse of the overlying weak strata creates a stress-reducing zone. As mining continues and the delamination expands, the thick hard rock strata gradually bend and sink under their own weight and the load of the overlying strata they control. This results in a large overhang, placing the thick hard rock strata in a stress-increasing zone. When the working face advances and reaches the critical breaking step of the thick hard rock strata, initial fracture occurs in the stress-reducing zone, releasing accumulated elastic energy and inducing mine tremors. Because the initial fractured blocks of the thick hard rock are large, they interlock and rotate, forming a three-hinged arch equilibrium. This structural morphology presents a "V" shape, with the tip of the "V" in contact with the floor. Subsequently, as the working face advances, the thick hard rock begins to fracture periodically. Locally, the blocks above the working face, supported by their own strength and the underlying coal body, articulate with the rock blocks behind the goaf, forming an "inverted V" shape. This leads to a sharp increase in stress ahead of the working face. Overall, the fractured rock blocks in the middle of the goaf are compacted and the separation space disappears, creating a "U"-shaped overall structure. This causes the stress in the central goaf, where the gangue is in contact, to slowly recover (below the original rock stress), resulting in a subsidence basin at the surface.

[0049] In one example, numerical simulation analysis using UDEC6.0 was conducted to analyze the collapse of overlying mudstone and the fracturing of thick hard rock strata following deep coal mining along the strike of the downhill coal pillar. A model measuring 1200 m x 795 m was constructed along the strike of the downhill coal pillar. The physical and mechanical parameters of the rock formations were determined by consulting columnar lithologic maps and geological exploration data for the mining area. The detailed parameters are shown in Table 1.

[0050]

[0051] Table 1 Physical and mechanical parameters of coal rock

[0052] The rock stratum joint division adopts staggered overlap, the joint block size of the thick hard rock layer is expanded, and the joint block size of the mudstone layer close to the coal seam is dense. The horizontal displacement of the model is restricted, the vertical displacement of the bottom edge is restricted, and the top is a free surface. The constitutive model adopts Mohr-Coulomb and the joint method adopts surface contact. The numerical model is established as follows Figure 4 shown.

[0053] The average mining height of the simulated working face is 12m. During excavation, 100m wide boundary coal pillars are reserved at both ends of the coal seam to eliminate boundary effects. The working face is then advanced 100m to the right from 100m on the left side of the model, and advanced to 200m, 300m, 400m, 500m, 600m, 700m, 800m, 900m, 1000m, and 1100m respectively. A total of 10 advancement plans are made. The vertical displacement cloud map of the overburden at each advancement is obtained, as shown in the figure below. Figure 5On this basis, the movement changes of the overlying strata during the advancement of the working face of the lower coal pillar are analyzed.

[0054] Depend on Figure 5 The maximum fracture step distance for this extremely thick conglomerate layer is 600 meters. When the working face advances within 300 meters, the rock movement trend is relatively small. When the advance range is between 400 and 600 meters, the rock movement trend increases significantly, leading to initial fractures and the release of a large amount of accumulated elastic energy, inducing mine tremors and rapid surface subsidence. When the advance range exceeds 600 meters, the rock layer exhibits periodic fractures and continuously releases accumulated energy, further inducing mine tremors and causing "basin-shaped" surface subsidence, which adversely affects surface buildings. At the same time, vertical stress ahead of the working face will accumulate and increase, which is very likely to trigger a combined dynamic disaster of mine tremors and rock bursts, posing a threat to mine safety.

[0055] In one example, FLAC3D software based on continuous mechanical analysis was selected to perform numerical simulation analysis of the stress evolution during the mining of the downhill coal pillar.

[0056] The model is determined according to the actual mining situation. The coal pillars in the 21 mining area are perpendicular to the goaf on both sides. The longest mining distance between the goafs on both sides is 1,500 meters and the shortest is 500 meters. Considering the large scale of the model and the long post-processing time, the large goafs on both sides are simplified into two rectangles, each 600 meters wide and the length depends on the length of the coal pillars. At the same time, a 90-meter-wide coal pillar is set near the boundary outside the large goaf, and a 50-meter-thick coal seam is left in front and behind the coal pillars to eliminate the boundary effect. The final model size XYZ: 1700m×1000m×260m, such as Figure 6 shown.

[0057] The displacements in the X, Y, and Z directions of the bottom of the model are fully constrained, and the displacements in the left and right X directions and the front and back Y directions of the model are restricted. To highlight the effect of horizontal stress, the lateral pressure coefficient is set to 1.5. The top of the model is set as a free surface. The vertical stress from the ground to the top of the model is calculated based on the average density and burial depth of the upper rock layer. Formula 3-1 can be used to calculate 14.3 MPa, which is applied to the top free surface.

[0058] q = γH(1-1);

[0059] Where γ is the bulk density of the overlying rock layer, and H is the burial depth of the rock layer.

[0060] The detailed physical and mechanical parameters of the rock formation are shown in Table 1. The material properties are assigned according to the actual parameters, and the initial ground stress analysis is performed using the Mohr-Coulomb model to obtain the initial ground stress distribution diagram of the downhill coal pillar, as shown in Figure 7 shown.

[0061] Numerical simulations analyzing the evolution of mining-induced damage in the thick hard rock during the mining of the downhill coal pillar reveal that, before the initial mining face, large goaf areas on both sides had already caused plastic failure in the thick hard rock strata overlying the central portion of the coal pillar. The large goaf on the left side, in particular, severely damaged the upper portion of the thick hard rock strata. With the initial advancement of the first mining face, plastic failure of the roof was primarily distributed in the mudstone layer. When the working face advanced to 250 meters, roof failure extended into the thick rock strata. By 500 meters, the plastic zone of the overlying rock strata above the goaf had completely interpenetrated with the pre-mining plastic zone. Subsequently, after experiencing extensive roof overhang, the thick rock strata began to fracture and gradually fail, bending and sinking, causing the roof and floor of the goaf to contact and compact. Simultaneously, damage progressed deeper into the coal and rock strata, indicating a critical fracture step distance of 550 meters for this thick stratum. At this point, the energy released by the fracture of the thick rock strata is highly likely to induce a combined dynamic disaster of mine tremors and rock bursts.

[0062] S2: Based on the simulation results, a mechanical model is established in which the isolated coal pillar and the target rock layer are simultaneously subjected to uniformly distributed load and horizontal concentrated stress; the target rock layer is a very thick hard rock layer.

[0063] Through numerical simulation analysis, it is known that during the advancement of the working face, the thick hard rock layer will experience delamination, bending and sinking, and the stress will change dynamically between increasing and decreasing. After experiencing a large area of ​​overhanging roof, the thick hard rock will undergo the initial fracture and release a large amount of elastic energy. After that, the overburden layer will experience multiple cycles of fracture, such as Figure 8 As shown. Figure 8 As can be seen in the figure, before the initial fracture of the thick hard rock, the coal pillar consisted of solid coal at both ends, forming a statically indeterminate beam with a fixed boundary. After the initial fracture, the working face continued to advance, and the solid coal in the goaf was converted into collapsed rock, providing support for the thick hard rock. Therefore, during the cyclic fracture period, the beam structure transformed into a statically indeterminate beam with one end hinged and the other end fixed.

[0064] Assume that the thick hard rock is a homogeneous and isotropic continuous medium. Since the deformation of the thick hard rock before collapse is small, it is considered as a plane problem before fracture, and the hyperstatic beam is split into the superposition of two statically determinate beams, and a Figure 9 The thick hard rock layer shown in the figure is fractured for the first time. Figure 10 The basic mechanical model of periodic fracture of thick hard rock layer is shown in Figure 1. Figure 9 and Figure 10 As shown, q is the uniformly distributed load of the thick hard rock layer and the overlying rock layer; L c L is the distance the working face advances when the thick hard rock first breaks. z is the length of the exposed thick hard rock before periodic fracture; h is the thickness of the thick hard rock layer; the width of the thick hard rock is taken as unit length.

[0065] against Figure 9 The stress distribution of the initial fracture mechanics model of thick hard rock layer is solved. Figure 9 In (a), the normal stress in the x-direction, the normal stress in the y-direction, and the tangential stress are (σ x ) c 、(σ y ) c 、(τ xy ) c , Figure 9 In (b), the normal stress in the x-direction, the normal stress in the y-direction, and the tangential stress are Figure 9 In (c), the normal stress in the x-direction, the normal stress in the y-direction, and the tangential stress are According to the superposition principle in elastic mechanics, we can get:

[0066]

[0067] for Figure 9 The stress components of the statically determinate beam in (b) can be calculated based on the knowledge of elastic mechanics:

[0068]

[0069] for Figure 9 The stress components of the statically determinate beam in (c) can be calculated from the elastic mechanics based on the pure bending problem of the rectangular beam as follows:

[0070]

[0071] Where M is the bending moment at both ends of the clamped beam under uniform load, which is known from structural mechanics:

[0072] Substituting equations (2-2) and (2-3) into equation (2-1), we can obtain Figure 9 The stress components of the beam clamped at both ends in (a) under uniformly distributed load are:

[0073]

[0074] against Figure 10 The mechanical model of periodic fracture of thick hard rock is used to solve its stress distribution. Figure 10 In (a), the normal stress in the x-direction, the normal stress in the y-direction, and the tangential stress are (σ x ) z 、(σ y ) z 、(τ xy ) z , Figure 10 In (b), the normal stress in the x-direction, the normal stress in the y-direction, and the tangential stress are Figure 10 In (c), the normal stress in the x-direction, the normal stress in the y-direction, and the tangential stress are According to the superposition principle in elastic mechanics, we can get:

[0075]

[0076] for Figure 10 The stress components of a simply supported statically determinate beam with uniform load in (b) can be calculated based on the knowledge of elastic mechanics:

[0077]

[0078] In addition, for Figure 10 In (c), the deformation problem of the statically determinate beam requires the use of a semi-inverse solution to obtain the stress components. Figure 10 The upper surface of (c) is not subjected to force, which means that there is no longitudinal compression between them. Assuming this, we can obtain:

[0079]

[0080] Where, is the stress function.

[0081] Integrating equation (2-7) twice, we can get the stress function:

[0082]

[0083] Where f1(y) and f2(y) are stress functions and are arbitrary functions.

[0084] Substitute equation (2-8) into the biharmonic equation have:

[0085]

[0086] Since formula (2-9) should be valid for any value x, we have:

[0087]

[0088] The integral for this is:

[0089] f1(y)=Ay 3 +By 2 +Cy+I,f2(y)=Dy 3 +Ey 2 +Jy+K (2-11);

[0090] Where A, B, C, D, E, J, I, and K are all constants.

[0091] Omit the linear terms and constant terms that have no effect on the stress components in formula (2-11) to obtain the stress function expression:

[0092]

[0093] Then we can get the corresponding stress component expression:

[0094]

[0095] The following uses Figure 10 The boundary conditions in (c) determine the constants:

[0096] At the upper and lower major boundaries of the beam:

[0097]

[0098] Combining equations (2-13) and (2-14), we can get: B = 0,

[0099] exist At the small boundary on the left side of the beam, using the Saint-Venant principle, we get:

[0100]

[0101] Combining equations (2-13) and (2-15), we can get: E = 0, Combine the equations for the unknown quantities in the above formula:

[0102] The solution is

[0103] Substituting the calculated unknown quantity into formula (2-13) we can get Figure 10 The stress components of the beam in (c) are:

[0104]

[0105] Substituting equations (2-6) and (2-17) into equation (2-5) yields Figure 10 Stress components of the statically indeterminate beam in (a) before cyclic fracture:

[0106]

[0107] Once the stress components before the initial and periodic fractures of the coal pillar are known, the fracture behavior can be determined based on strength theory under complex stress states. For brittle beams such as thick hard rock beams, the maximum tensile stress criterion states that fracture will occur as long as the maximum tensile stress exceeds the ultimate tensile strength of the material. From material mechanics, the formula for calculating the principal stress under plane stress states is:

[0108]

[0109] Among them, the maximum normal stress σ max =max(σ1,σ2).

[0110] Since the initial yield point of the statically indeterminate beam at the initial fracture is located at the lower boundary of the model The first yield point of the statically indeterminate beam during cyclic fracture is the end of the model The lower boundary point before the first fracture The stress component formula (2-4) and the front end point of the periodic fracture Substituting the stress components of formula (2-18) into formula (2-19), we can obtain the maximum tensile stress (σ max ) c and the maximum tensile stress (σ max ) z When the maximum tensile stress is greater than the ultimate tensile strength of the thick hard rock layer [σ t ], the rock layer will be pulled apart. Therefore, the fracture mechanical condition of the thick hard rock layer overlying the isolated coal pillar without horizontal stress can be expressed as:

[0111]

[0112] During the mining process, the roof will fall, fracture, and other movements, resulting in the redistribution of the original rock stress field. Vertical stress will be transferred to the surrounding areas of the goaf, while horizontal stress will be transferred to the overlying stable rock layer. As a result of this stress redistribution, stress concentration will occur in the local area of ​​the roof and floor in the middle of the goaf, leading to the accumulation of elastic energy. Figure 11 shown.

[0113] exist Figure 11 In the figure, after the solid coal on both sides of the coal pillar is mined, it can be found that the surrounding horizontal stress will be transferred to the unmined solid coal on both sides. The horizontal stress along the coal pillar dip direction is transferred to both sides of the goaf, which has little impact on the coal pillar. However, part of the horizontal stress in the goaf along the direction of the coal pillar will be transferred to the coal pillar, making the horizontal stress on the coal stratum of the downhill coal pillar become the superposition of the original stress and the transferred stress. Assuming that the dip lengths of the goaf on both sides of the coal pillar are and respectively, and the dip length of the island coal pillar working face is, then according to the horizontal stress transferred from the adjacent working face to the island working face, the horizontal stress is distributed in a triangle, and the average stress increment on the island working face can be obtained as:

[0114]

[0115] Where, is the transfer coefficient of horizontal stress from adjacent goaf to isolated coal pillar on the plane,

[0116] Thus, the change of horizontal stress at the working surface of the isolated coal pillar can be obtained, that is, the average stress increment after the goaf transfer is superimposed, and the horizontal stress σ1 of the coal pillar is obtained as follows:

[0117]

[0118] When the working face is not mined, the original stress is evenly distributed with the burial depth, and the horizontal stress in the deeply buried rock layer is close to the vertical stress. After the working face is mined, the horizontal stress in the goaf will show a stress reduction in the roof fracture area. Since the rock stratum is broken in rock stratum groups, when the roof is broken, the overlying rock stratum has not yet broken, so the horizontal stress accumulated in the bearing layer will be transferred to the overlying intact rock stratum. When the working face continues to be mined, the horizontal stress continues to transfer to the overlying intact rock stratum after the rock stratum breaks, and this process is repeated until it reaches a very thick hard rock stratum. Due to the characteristics of very thick hard rock stratum that is not easy to break, the horizontal stress will be concentrated in this rock stratum. Based on this, a simplified model of horizontal stress transfer in the height direction can be established, such as Figure 12 shown.

[0119] In the original state, the coal rock layer is assumed to have thicknesses of T1, T2, T3, T4 and T5, and the original horizontal stresses it is subjected to are σ1, σ2, σ3, σ4 and σ5. The horizontal stresses concentrated before the rock layer breaks during mining are σ2′, σ3′, σ4′ and σ5′. Assume that after the working face is mined, the overlying rock layer breaks layer by layer from bottom to top, and the horizontal stress of the bearing layer after breaking is only transferred to the adjacent unbroken rock layer. Figure 12 From (b), we can see that: Assuming that after the first group of rock layers breaks, the coefficient of the horizontal stress of the bearing layer transferred to the adjacent second group of rock layers in the height direction is β1, the horizontal stress accumulated in the second group of rock layers can be obtained as Similarly, assuming that the coefficients of transfer of the second, third and fourth groups to the adjacent bearing stratum are β2, β3 and β4, then:

[0120]

[0121] From formula (2-24), we can summarize the law of horizontal stress transfer along the height direction, and get the horizontal stress σ accumulated before the fracture of the nth group of rock layers: n 'for:

[0122]

[0123] Formula (2-24) refers to the concentrated horizontal stress of the adjacent intact rock layer obtained by superimposing the first set of original horizontal stress and the horizontal stress transfer after fracture. Since the isolated coal pillar is affected by the goaf on both sides, its original horizontal stress has changed. The horizontal average stress σ1 after the change is formula (2-23). ​​Substituting it into formula (2-25), the stress concentration σ caused by the horizontal stress transfer in the height direction of the isolated coal pillar can be obtained. n 'for:

[0124]

[0125] According to formula (2-26), the thickness of the coal seam is T1 = 11m, the thickness of the mudstone layer is T2 = 49m, and the thickness of the conglomerate layer is T3 = 649m, totaling 3 layers. At the same time, the stress transfer coefficient β is taken as 0.6, Taking 0.5, L1, L2, and L3 according to the length of the working face, the horizontal concentrated stress of the thick hard rock layer overlying the isolated coal pillar can be obtained as follows:

[0126]

[0127] Then, by integrating the horizontal stress over the cross-sectional area (width per unit length) of the thick conglomerate layer, the horizontal force F can be obtained as:

[0128]

[0129] In one example, the effect of the horizontal stress on the fracture span of a beam fixed at both ends after the horizontal stress is transferred to the overlying thick hard rock layer and generates horizontal concentrated stress is studied. Figure 13 As shown, where y(x) is the deflection function, F sx For shear force.

[0130] According to the equilibrium condition of beams in material mechanics, the bending moment equation of a clamped beam under the combined action of a uniformly distributed load q and the horizontal force F at both ends is:

[0131]

[0132] According to the knowledge of elastic mechanics, the differential equation of beam bending deformation is:

[0133]

[0134] Where E is the elastic modulus of the thick rock beam, and I is the moment of inertia of the thick rock beam section.

[0135] Substituting equation (2-29) into equation (2-30) yields the second-order linear nonhomogeneous ordinary differential equation:

[0136]

[0137] For equation (2-31), we need to first find the general solution of the homogeneous equation and a special solution of the non-homogeneous equation. Finally, the general solution is:

[0138]

[0139] Where, C1 and C2 are constants.

[0140] Using the boundary conditions of the clamped beam, at (x=0, y=0) and (x=L c , y = 0), that is, the bending moment at the deflection function y, y′ = 0, substituting it into formula (2-32) yields the constant term So the deflection function is:

[0141]

[0142] Because in the beam span At the point where the deflection is the maximum deflection y max ,Will Substituting into formula (2-32) we can get:

[0143]

[0144] Equation (2-34) shows that the deflection y decreases with increasing horizontal concentrated stress F, thereby suppressing the growth of the deflection. This indicates that the overhang span of the hard rock beam gradually increases with increasing horizontal concentrated stress. Greater horizontal concentrated stress increases the fracture step length of the hard rock layer, leading to a large amount of elastic energy stored in the hard rock layer. When the hard rock layer reaches the critical fracture length, the accumulated elastic energy is released in the form of mining earthquakes. Conversely, when the horizontal concentrated stress is low, the fracture step length of the hard rock layer is shorter, the number of fractures increases, and the accumulated energy is gradually released.

[0145] To further illustrate the relationship between horizontal stress and the initial fracture step, the maximum tensile stress of a beam clamped at both ends under simultaneous bending moment and horizontal concentrated stress is listed, that is, the algebraic sum of the maximum bending tensile stress of the beam under uniformly distributed load (Formula (2-20)) and the horizontal concentrated stress:

[0146]

[0147] When the maximum tensile stress σ max Greater than the ultimate tensile strength of the beam [σ t ], the beam will break. max =[σ t ]Substituting into formula (2-35), we can obtain the initial fracture step distance L of the rock beam under uniform load and horizontal concentrated stress F. c for:

[0148]

[0149] Since the horizontal force transmission is cut off after the rock beam has experienced the initial fracture, it is no longer affected by the horizontal force during the periodic fracture. The maximum tensile stress of formula (2-21) can be used to directly obtain the periodic fracture step distance L. z for:

[0150]

[0151] S3: Based on the mechanical model, deriving dynamic and static load stress expressions caused by the fracture and instability of the target rock formation;

[0152] Through the simulation results, the evolution law of overburden movement and the corresponding new stress field formed during the mining of the downhill coal pillar were obtained. In order to more clearly understand the energy accumulation state during the overburden movement, the energy change during the mining process was further obtained through the stress-strain relationship, which laid the foundation for the study of overburden mine vibration load. According to these findings, mine vibration mainly comes from the dynamic load generated by the movement of the thick hard rock in the key layer during the initial fracture and periodic fracture process, and at the same time, the working face is subjected to high stress load to form static load. The dynamic and static load diagrams are shown as follows: Figure 14 shown.

[0153] exist Figure 14 It can be seen that as the working face advances, the extremely thick hard rock layer and the lower rock layer first separate, and then a large area of ​​hanging roof is formed. Finally, under the combined action of the extremely thick hard rock layer's own weight and the load of the overlying rock layer, the extremely thick hard rock layer slowly bends and sinks, and then the load is transferred to both sides of the goaf and transmitted to the working face through the rock mass below. As the working face continues to advance, the extremely thick hard rock layer first reaches the initial fracture, and then reaches the periodic fracture, and the fracture will be accompanied by mine earthquakes, thereby forming dynamic load stress. Dynamic load stress is the strain energy U stored in the rock mass when the extremely thick hard rock layer bends and deforms under the action of its own weight and overlying load. According to the reciprocity theorem, the strain energy U can be expressed as:

[0154]

[0155] Typically, the energy released by fractures in thick, hard rock formations is mostly released in other forms, such as heat, resulting in low seismic efficiency. The energy released by the seismic waves during an earthquake is only 0.26% to 3.60% of the total strain energy. Furthermore, because the rock formation is heterogeneous, the energy of the seismic waves further attenuates as it propagates toward the working face. Its attenuation function is approximately:

[0156] U r =ηUr -δ (3-2);

[0157] Where: U rIt is the energy finally received by the seismic wave after propagating a certain distance; r is the distance from the earthquake source to the working surface; δ is the energy attenuation coefficient, which is related to the energy of the earthquake source and the properties of the rock formation.

[0158] According to the knowledge of physics, it can be obtained that the working surface receives energy U r The dynamic load D generated is:

[0159]

[0160] Where: a is the acceleration generated in the rock formation; Ta and va are the time and velocity of the coal body at the working face affected by the vibration wave, respectively; ρ is the density of the coal body; b is the length of the working face along the dip; v and t are the pushing speed and pushing time of the working face, respectively.

[0161] By combining equations (2-34), (3-1), (3-2), and (3-3), we can obtain the expression for the dynamic load D generated by the mine earthquake on the working face when the thick hard rock layer breaks:

[0162]

[0163] exist Figure 14 As shown in (b), the supporting rock layer below collapses as the critical working face blocks advance, and the load of the uncollapsed rock layer is applied to the critical working face blocks. At the same time, the rock layer near the critical working face blocks cannot fully collapse due to the coal body boundary effect. The rock layer between the contact line and the rock migration line forms a cantilever rock layer, half of which is borne by the critical working face blocks. The superposition of the supporting rock layer and the cantilever rock layer causes the working face to be subjected to a high static load stress S, which can be expressed by formula (3-5):

[0164]

[0165] Where, γ is the average bulk density of the rock layer; α and β are the rock migration angle and the rock contact angle respectively; h k It is the vertical distance from the coal seam to the thick hard rock layer.

[0166] S4: Based on the dynamic and static load stress expressions, combined with the dynamic and static load superposition theory, a discriminant formula for the combined dynamic disaster of mine earthquake and rock burst is constructed.

[0167] When large goafs are located on either side of a coal pillar, the vertical stress above the pillar shifts from the original weight of the overburden to the combined weight and the stress transferred from the overburden in the large goafs. This results in a high stress state in the deep-buried coal pillar. When this high horizontal stress exceeds the overall bearing capacity of the coal pillar, the pillar may experience a rock burst, which can lead to overall instability. In addition to stress changes in the vertical direction, horizontal stresses surrounding the coal pillar also transfer into the pillar. As the mining face advances, the overburden strata along the strike of the working face fracture sequentially from bottom to top, and horizontal stresses transfer to higher strata as they fracture. When horizontal stresses are transmitted to the extremely thick hard rock strata, they concentrate there due to their high tensile strength and resistance to damage. Based on the above example analysis, the presence of horizontal stresses prevents the extremely thick hard rock strata from fracturing, preventing the release of their flexural elastic energy, which is instead stored. Simultaneously, the upper portion of the extremely thick overburden, affected by the goafs on both sides, experiences triaxial stress concentrations in its center, which have already caused micro-fractures and further accumulated significant elastic energy. When the damage reaches the limit span of the hard rock layer, the first fracture occurs. The accumulated energy is suddenly released, which in turn induces the first strong mine tremor. As the mining face continues to advance, the thick hard rock reaches a stable sinking stage in the goaf, and appears in a cantilever beam state above the working face. The bending of the rock beam makes the coal body bear a large load and is in a compressed state. When the bending breaking strength of the rock beam exceeds its own tensile strength, periodic fracture will occur, resulting in the second mine tremor, such as Figure 15 This process reveals the dynamic mechanism of stress evolution and mine earthquake occurrence in thick hard rock layers during mining.

[0168] According to the principle of energy conservation, energy will not disappear in vain, but will only be transferred. Therefore, when a strong mine earthquake occurs in a thick hard rock layer, its energy will be transferred to the mining face in the form of mine earthquake elastic waves. According to the theory of dynamic and static load superposition induced impact, when the static load stress in the coal and rock mass around the mining area is superimposed with the dynamic load stress generated by the mine earthquake, and exceeds the critical stress required for the destruction of the coal and rock mass system, it will cause coal pillar impact disasters, such as Figure 16 shown.

[0169] Therefore, when the dynamic load D generated by the mine tremor and the static load S in the coal body, when combined, exceeds the critical support strength RD when rock burst occurs, a compound dynamic disaster is induced. Based on the above example, the dynamic load D can be expressed using Equation (3-4), and the static load S can be expressed using Equation (3-5). Ultimately, the discriminant formula for the dynamic disaster caused by the combined effects of mine tremors and rock bursts in a thick, hard rock downhill coal pillar under horizontal concentrated stress is obtained as follows:

[0170]

[0171] The above analysis reveals the primary mechanism by which mine tremors induce rock bursts: The overlying thick hard rock layer, serving as the primary critical layer, is resistant to collapse after coal seam excavation, remaining suspended and accumulating significant elastic energy in the downwardly curved sections. Furthermore, the coal walls at the goaf cuts and working faces support the overburden, generating high vertical stresses. When the critical impact state is reached, these high stresses trigger static shocks. When the thick hard rock layer suddenly fractures, the accumulated high energy is released, generating a strong mine tremor. This, combined with the high static loads at the coal walls, triggers rock bursts, resulting in a combined dynamic shock. This process reveals the evolutionary mechanism of the combined disaster of mine tremors and rock bursts.

[0172] S5: Predicting the occurrence of a combined dynamic disaster of mine earthquake and rock burst according to the discriminant.

[0173] The discriminant of formula (4-1) combines factors such as static load, dynamic load and structural parameters. When the discriminant is greater than or equal to a critical value R D When the earthquake occurs, it is judged that a combined dynamic disaster of mine earthquake and rock burst may occur.

[0174] The parameters required for the discriminant are collected through geological materials and mine field detection systems, and the parameters are substituted into the discriminant to calculate the left side value of the discriminant, and then the left side value is compared with the critical value R D Compare, if the left value ≥ R D , then the area is judged to be a high-risk area, there is a possibility of compound dynamic disasters, and early warning is required; if the left value <R D , then the area is judged to be low risk and no early warning measures will be taken for the time being. At the same time, high-risk areas can be spatially marked in the mine area GIS system to output early warning signals.

[0175] According to one embodiment of the present application, a system for distinguishing a combined dynamic disaster of mine earthquake and rock burst is provided, using the method provided in the above example, such as Figure 17 As shown, the system includes a simulation module 10 , a mechanical modeling module 20 , a stress expression derivation module 30 and a disaster identification module 40 .

[0176] Specifically, the simulation module 10 is used to perform numerical simulation of the overburden movement evolution and stress field evolution based on geological data to obtain simulation results; the mechanical modeling module 20 is used to establish a mechanical model in which the isolated coal pillar and the target rock layer are simultaneously subjected to uniformly distributed loads and horizontal concentrated stresses based on the simulation results; the stress expression derivation module 30 is used to derive the dynamic load stress and static load stress expressions generated during the fracture and instability of the target rock layer based on the mechanical model; the disaster identification module 40 is used to combine the dynamic and static load stress expressions based on the dynamic and static load superposition theory to form a discriminant for the combined dynamic disaster of mine earthquake and impact ground pressure, and use it for disaster identification.

[0177] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "exemplary" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification and features of different embodiments or examples, unless they are mutually inconsistent.

[0178] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A method for distinguishing a combined dynamic disaster of mine earthquake and rock burst, characterized in that: include: Numerical simulation of overburden movement evolution and stress field evolution is performed based on geological data to obtain simulation results; According to the simulation results, a mechanical model of the isolated coal pillar and the target rock layer being subjected to uniformly distributed load and horizontal concentrated stress is established; Derivation of dynamic and static load stress expressions caused by the fracture and instability of the target rock formation based on the mechanical model; Based on the dynamic and static load stress expressions and combined with the dynamic and static load superposition theory, a discriminant formula for the combined dynamic disaster of mine earthquake and rock burst is constructed; The occurrence of a combined dynamic disaster of mine earthquake and rock burst is predicted based on the discriminant.

2. The method according to claim 1, characterized in that The numerical simulation of overburden movement evolution and stress field evolution based on geological data includes: The movement of overburden rocks during the advancement along the working face was simulated by UDEC to obtain the limit fracture step of overburden rocks. By simulating the mining process of the working face along the coal pillar through FLAC3D, it is found that when the working face is pushed to the limit fracture step, the overburden deflection exceeds the critical value.

3. The method according to claim 1, characterized in that The mechanical model of the isolated coal pillar and target rock formation subjected to uniformly distributed load and horizontal concentrated stress includes: The isolated coal pillar is simplified into a beam with fixed supports at both ends. The maximum tensile stress and mechanical fracture condition when the target rock beam is broken are obtained by combining the mechanical mechanism of rock beam fracture with elastic mechanics and material mechanics. According to the source of horizontal stress during the mining process, the expression of horizontal concentrated stress on the target rock layer is obtained; The influence of the uniformly distributed load and horizontal concentrated stress on the fracture of the isolated coal pillar is analyzed, and the fracture span of the target rock layer under the action of horizontal concentrated stress is obtained through mechanical model combined with material mechanics calculation.

4. The method according to claim 3, characterized in that The derivation of dynamic and static load stress expressions caused by the fracture and instability of the target rock formation includes: deriving the ultimate span expression of the target rock formation through the reciprocity theorem of work, as well as the dynamic load stress expression and static load stress expression generated by the mine earthquake on the working face during fracture.

5. The method according to claim 3, characterized in that The mechanical model includes: splitting the isolated coal pillar as an indeterminate beam into a superposition of a first statically determinate beam and a second statically determinate beam, and constructing a first model when the target rock formation is initially fractured and a second model when the target rock formation is periodically fractured; Wherein, for the first model, the stress distribution of the target rock formation is solved: The stress components of the first statically determinate beam are obtained by elastic mechanics calculation; The stress components of the second statically determinate beam are obtained by calculating the bending moment and elastic mechanics of the rectangular beam; Calculating the stress components of the clamped beams at both ends of the isolated coal pillar under a uniformly distributed load based on the stress components of the first statically determinate beam and the stress components of the second statically determinate beam; For the second model, the stress distribution of the target rock formation is solved: The stress components of the first statically determinate beam are obtained by elastic mechanics calculation; The stress components of the second statically determinate beam are obtained by semi-inverse solution and elastic mechanics calculations; The stress components of the clamped beams at both ends of the isolated coal pillar under a uniformly distributed load are calculated based on the stress components of the first statically determinate beam and the stress components of the second statically determinate beam.

6. The method according to claim 5, characterized in that According to the stress components before the initial fracture and periodic fracture of the isolated coal pillar, the fracture condition of the isolated coal pillar is judged according to the strength theory under complex stress state. For the target rock formation, according to the maximum tensile stress criterion, the fracture mechanical conditions of the target rock formation of the isolated coal pillar under the action of no horizontal stress are obtained.

7. The method according to claim 3, characterized in that According to the source of horizontal stress during the mining process, the expression of horizontal concentrated stress on the target rock layer is obtained as follows: When the solid coal on both sides of the island coal pillar is mined, the horizontal stress of the adjacent working face is transferred to the horizontal stress on the island working face in a triangular distribution, and the average stress increment on the island working face is obtained; According to the average stress increment, the change of horizontal stress on the working surface of the isolated coal pillar is obtained, and the horizontal stress of the isolated coal pillar is obtained; When the working face is mined, a height-direction horizontal stress transfer model is established; According to the horizontal stress transfer model, the horizontal stress transfer law along the height direction is obtained; According to the horizontal stress transfer law, the horizontal concentrated stress of the target rock layer on the isolated coal pillar is obtained.

8. The method according to claim 4, characterized in that The dynamic and static load stress expressions include: Dynamic stress is the strain energy stored in the rock mass when the target rock layer bends and deforms under its own weight and overburden load. The strain energy is calculated based on the reciprocity theorem. According to the attenuation function of energy in the process of propagating to the working surface, the dynamic load generated by the working surface after receiving the attenuated energy is obtained; Obtain the dynamic load stress generated by mining earthquake on the working face when the target rock layer breaks; The static load stress generated on the working surface is obtained by superimposing the supporting rock layer below the target rock layer and the cantilever rock layer on one side.

9. The method according to claim 8, characterized in that When the dynamic load stress generated by mine earthquake and the static load stress in the coal body are superimposed and are greater than the critical support strength when rock burst occurs, the discriminant formula for the dynamic disaster caused by the combination of mine earthquake and rock burst under the action of horizontal concentrated stress is obtained based on the calculated dynamic load stress and static load stress.

10. A system for distinguishing a combined dynamic disaster of mine earthquake and rock burst, using the method according to any one of claims 1 to 9, characterized in that: include: The simulation module is configured to perform numerical simulation of overburden movement evolution and stress field evolution according to geological data to obtain simulation results; a mechanical modeling module configured to establish a mechanical model of the isolated coal pillar and the target rock formation being subjected to uniformly distributed load and horizontal concentrated stress simultaneously according to the simulation results; a stress expression derivation module configured to derive, based on the mechanical model, expressions for dynamic stress and static stress generated during the fracture and instability of the target rock formation; The disaster identification module is configured to combine the dynamic and static load stress expressions according to the dynamic and static load superposition theory to form a discriminant formula for the combined dynamic disaster of mine earthquake and rock burst, and use it for disaster identification.

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