A method and system for analyzing critical filling rate of coal mine filling working face for anti-bumping

Abstract

The present application relates to the field of coal mine safety technology and provides a method and system for analyzing the critical filling rate of coal mine filling working face. In this method, first, the critical impact-causing key layer w of the overlying rock stratum of the filling working face is determined; then, based on the critical impact-causing key layer w, the critical control fracture height H of the filling working face for impact prevention is determined. min Finally, when the overburden movement height reaches the critical fracture state of the critical impact layer w when the filling material is filled into the filling working face, the fracture height H is controlled according to the impact critical control. min , determine the critical filling rate k of the filling working face for anti-bumping. In this way, the critical filling rate of the filling working face for anti-bumping can be determined scientifically and accurately, providing a theoretical reference for the design and monitoring of the filling rate of the on-site filling working face. This can avoid the poor control effect of the overburden strata caused by blindly designing the filling rate of the filling working face, or even induce problems such as impact, and ensure efficient and safe production of the filling working face in the coal mine.

Description

Technical Field

[0001] The present application relates to the field of coal mine safety technology, and in particular to a method and system for analyzing the critical filling rate for anti-bumping of a coal mine filling working face. Background Art

[0002] The dynamic load disturbance caused by rock movement in different layers on the underground working face is heterogeneous. Among them, compared with other forms of movement, the key layer (i.e., the impact-causing key layer) covered with one or more layers of dynamic load disturbance above the working face, which triggers potential impact accidents, releases more intense dynamic load disturbance during the first rupture movement and has the most significant impact on the working surface.

[0003] The rupture and subsidence of the thick hard rock layer overlying the coal mining face is one of the main factors leading to rock burst. The main reason is that the large amount of elastic potential accumulated in the key rock burst layer is released instantaneously during its first rupture movement, thereby triggering rock burst on the working face, posing a serious threat to the efficient and safe mining of underground coal mines.

[0004] Backfill mining technology can effectively slow the movement of overlying strata above the coal working face, preventing rock bursts. In recent years, it has been gaining recognition and application in many coal mines. The backfill fill rate, a key indicator in backfill working face design, reflects the effectiveness of the backfill in controlling the overburden. However, the current lack of a rational design method for backfill fill rates in anti-bumping coal mines directly impacts the effectiveness of backfill mining in preventing rock bursts. Summary of the Invention

[0005] The purpose of this application is to provide a method and system for analyzing the critical filling rate of coal mine filling working face anti-bumping, so as to solve or alleviate the problems existing in the above-mentioned prior art.

[0006] In order to achieve the above objectives, this application provides the following technical solutions:

[0007] The present application provides a method for analyzing the critical filling rate of the filling working face for preventing impact, comprising: step S101, determining the critical impact-inducing key layer w of the overlying rock stratum of the filling working face; step S102, determining the critical control fracture height H of the filling working face for preventing impact based on the critical impact-inducing key layer w. min Step S103, in response to the filling working face filled with filling material when the overburden movement height reaches the critical fracture state of the critical impact layer w, according to the anti-impact critical control fracture height H min , determine the critical filling rate k of the filling working surface for anti-collision.

[0008] Preferably, in step S101, according to the formula:

[0009]

[0010] Determine the critical impact-causing key layer w of the overlying rock formation on the filling working face;

[0011] in, is the equivalent additional disturbance stress generated by the initial breaking of n layers of overlying strata in the filling working face on the filling working face, V m is the propagation velocity of the mine shock wave in the filling working face, p n is the energy effect coefficient of the mine tremor caused by the movement of the nth layer of overlying rock, η n is the release efficiency of the mining shock wave during the movement of the nth layer of overlying rock, q n is the weight of the nth overlying rock layer and the additional unit length converted load of the upper rock layer, L n is the initial breaking step of the nth overlying rock layer, b n is the suspended span of the nth overlying rock layer, ρ t is the average medium density of the coal and rock mass through which the movement of the nth overlying rock layer is propagated; n is the attenuation coefficient of the mining shock wave of the nth layer of overlying rock, S n is the distance from the earthquake source of the nth layer of overburden movement to the filling working surface, E n is the elastic modulus of the nth overlying rock layer, h n is the thickness of the nth overlying rock layer;

[0012] I n is the stress concentration factor of the filling working surface, σ s is the static stress of the coal body at the filling working face, [σ c ] is the uniaxial compressive strength of the coal body at the filling working face; j is the key layer causing impact at the filling working face, I j It is the concentrated stress of the coal body after the filling working face is affected by the initial rupture of the key layer j causing impact.

[0013] Preferably, in step S102, according to the formula:

[0014]

[0015] Determine the critical control fracture height H of the filling working surface min ;

[0016] in, is the ultimate deflection of the critical impact-causing key layer w during the sinking process at the critical state of sinking limit, q w is the uniformly distributed load on the critical impact layer w, l w is the overhanging length of the overburden beam in the stope of the critical impact-causing key layer w, E w is the elastic modulus of the critical impact layer w, Iw is the moment of inertia of the critical impact layer w; H w is the vertical distance between the top plate of the critical impact-causing key layer w and the coal body of the working face.

[0017] Preferably, in step S103, in response to the critical impact-inducing key layer w being located in the immediate loading zone, according to the formula:

[0018]

[0019] Determine the critical filling rate k of the filling working surface; where K A is the expansion coefficient of the rock in the instant loading zone, H min is the critical control fracture height of the filling working face for anti-impact; h0 is the actual mining height of the filling working face; and α is the final destruction index of the filling body of the filling working face.

[0020] Preferably, in step S103, in response to the critical impact-inducing key layer w being located in the delayed loading zone, according to the formula:

[0021]

[0022] Determine the critical filling rate k of the filling working surface; where K A is the expansion coefficient of rock under instant loading, H min is the critical control fracture height of the filling working face, h0 is the actual mining height of the filling working face, α is the final destruction index of the filling body of the filling working face, K i k is the comprehensive expansion coefficient of the rock group from the critical impact-causing key layer w to the coal seam; i is the filling rate of the filling working surface.

[0023] The present application also provides a coal mine filling working face anti-bumping critical filling rate analysis system, comprising: a key layer identification unit, configured to determine the critical impact-inducing key layer w of the overlying rock strata of the filling working face; a critical control unit, configured to determine the anti-bumping critical control fracture height H of the filling working face based on the critical impact-inducing key layer w. min Filling rate unit, configured to respond to the filling working face filled with filling material when the overburden movement height reaches the critical state of the critical impact layer w, according to the anti-impact critical control fracture height H min , determine the critical filling rate k of the filling working surface for anti-collision.

[0024] Beneficial effects:

[0025] In the method for analyzing the critical filling rate of the coal mine filling working face provided in the embodiment of the present application, first, the critical impact-causing key layer w of the overlying rock stratum of the filling working face is determined; then, based on the critical impact-causing key layer w, the critical control fracture height H of the filling working face for impact prevention is determined. min Finally, in response to the overburden movement height reaching the critical fracture state of the critical impact layer w when the filling material is filled into the filling working face, the fracture height H is controlled according to the critical impact prevention min , determine the critical filling rate k of the filling working face for anti-bumping. In this way, the critical filling rate of the filling working face for anti-bumping can be determined scientifically and accurately, providing a theoretical reference for the design and monitoring of the filling rate of the on-site filling working face. This can avoid the poor control effect of the overburden strata caused by blindly designing the filling rate of the filling working face, or even induce problems such as impact, and ensure efficient and safe production of the filling working face in the coal mine. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The drawings and descriptions that constitute part of this application are intended to provide a further understanding of this application. The exemplary embodiments and descriptions of this application are intended to explain this application and do not constitute an improper limitation on this application. Among them:

[0027] Figure 1 A schematic flow chart of a method for analyzing the critical filling rate of a coal mine filling working face for anti-bumping according to some embodiments of the present application;

[0028] Figure 2 A schematic diagram of the initial breaking process of the top plate of the main control disaster-causing critical layer provided according to some embodiments of the present application;

[0029] Figure 3 A schematic diagram of a double-embedded beam model with clamps at both ends provided according to some embodiments of the present application;

[0030] Figure 4 A schematic diagram of the movement state of the roof of the overburden stratum when the filling rate of the filling working face is large according to some embodiments of the present application;

[0031] Figure 5 A schematic diagram of the movement state of the roof of the overlying rock formation when the filling working face reaches a critical filling rate according to some embodiments of the present application;

[0032] Figure 6 A schematic diagram of the movement state of the roof of the overburden stratum when the filling rate of the filling working face is low according to some embodiments of the present application;

[0033] Figure 7 This is a flow chart of a critical filling rate analysis system for anti-bumping of a coal mine filling working face provided according to some embodiments of the present application. DETAILED DESCRIPTION

[0034] The present application will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments. Each example is provided by way of explanation of the present application and does not limit the present application. In fact, it will be clear to those skilled in the art that modifications and variations can be made in the present application without departing from the scope or spirit of the present application. For example, a feature shown or described as part of one embodiment can be used in another embodiment to produce yet another embodiment. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention should fall within the scope of protection of the embodiments of the present invention.

[0035] To accurately describe the height change of the backfill after it enters the goaf, the ratio of the final backfill height to the coal cutting height when the overburden reaches a stable state is defined as the filling rate. However, current research on the filling rate of the backfill working face primarily focuses on controlling overburden movement and surface subsidence, lacking design criteria for the filling rate for anti-bumping work. Determining the critical filling rate for backfilling work faces, while considering the dynamic changes in coal seam conditions at the backfill working face, can ensure that the overburden strata that cause backfilling are controlled at a critical state of bending and subsidence, thus avoiding problems such as overburden fracture and impact caused by blindly designing the filling rate of the backfill working face.

[0036] Based on this, this application proposes a method for analyzing the critical filling rate of coal mine filling working face to provide a theoretical reference for the design and monitoring of on-site filling rate, and ensure the safe and efficient production of coal mine filling working face. Figure 1 As shown in the figure, the analysis method of critical filling rate for anti-bumping of filling working face in coal mine includes:

[0037] Step S101: Determine the critical impact-causing layer w of the overlying rock formation on the filling working face.

[0038] During coal mining, the immediate roof rock strata fall as the working face is mined, precluding the conditions for large-scale roof overhangs to undergo initial fracture and release energy, in other words, the conditions for mine tremors. However, as the mining area of ​​the underground working face increases, the overburden rock undergoes initial fracture, periodic fracture, rotation, or sliding settlement, all accompanied by energy release.

[0039] The dynamic load disturbances caused by rock movement at different strata vary. The impact-causing critical strata have the greatest impact on the working face. This refers to one or more layers overlying the backfill working face, where dynamic loads can potentially induce impact accidents. Compared to other forms of movement, the initial breaking motion of the impact-causing critical strata releases more intense dynamic loads.

[0040] In this application, whether a rock layer is a key layer is determined by considering factors such as the movement, deformation, and fracture characteristics of the overburden. It is generally a relatively thick and hard rock layer, but not all thick and hard rock layers in the overburden are key layers. The specific determining condition is that when the key layer breaks, the sinking deformation of all or part of the rock layers above it is coordinated with each other. Among them, all rock layers above the key layer become the main key layer of rock layer activity, and the local rock layers become sub-key layers. In other words, the fracture of the key layer will cause all or a considerable part of the overburden rock layer to move as a whole. There may be more than one sub-key layer in the overburden rock, while there is only one main key layer.

[0041] Here, based on the definition and characteristics of the static loading zone, it can be seen that the critical impact-inducing key layer w does not appear in the static loading zone. Here, the critical impact-inducing key layer w only appears in the immediate loading zone or the delayed loading zone.

[0042] Specifically, according to the formula:

[0043]

[0044] Determine the critical impact-causing layer w of the overlying rock formation on the filling working face. is the equivalent additional disturbance stress caused by the initial breaking of n layers of overlying strata in the filling working face, V m is the propagation velocity of the mine shock wave in the filling working face, p n is the energy effect coefficient of the mine tremor caused by the movement of the nth layer of overlying rock, η n is the release efficiency of the mining shock wave during the movement of the nth layer of overlying rock, q n is the weight of the nth overlying rock layer and the additional unit length converted load of the upper rock layer, L n is the initial breaking step of the nth overlying rock layer, b n is the suspended span of the nth overlying rock layer, ρ t is the average medium density of the coal and rock mass through which the mine shock wave propagates, λ n is the attenuation coefficient of the mining shock wave of the nth layer of overlying rock, S n is the distance from the earthquake source of the nth layer of overburden movement to the filling working surface, E n is the elastic modulus of the nth overlying rock layer, h n is the thickness of the nth overlying rock layer.

[0045] I n is the stress concentration factor of the filling working surface, σ s is the static stress of coal body at the filling working face, [σ c ] is the uniaxial compressive strength of the coal body at the filling working face, j is the key layer causing the impact of the filling working face, I jIt is the concentrated stress of coal body after the filling working face is affected by the rupture of the key layer j. j =1.5 is used as the critical identification index of the key layer causing impact in the filling working face, such as Figure 2 As shown in Figure 1, it is the sinking process of the critical impact-causing key layer when it first breaks.

[0046] Here, it should be noted that through the geological mining and on-site monitoring data of the coal mine filling working face, for the filling working face with the critical filling rate for anti-bumping, at least the coal seam occurrence conditions (uniaxial compressive strength, coal seam thickness) of the filling working face, the drilling column diagram, the layout parameters of the filling working face (working face length, working face mining height, movement angle of the overlying rock strata on the working face, etc.), the mechanical parameters of the coal and rock overlying the filling working face (elastic modulus, direct roof thickness, basic roof thickness, distance from the filling working face of the mine earthquake, crushing expansion coefficient of the low-level collapsed rock layer, comprehensive crushing expansion coefficient of the coal seam to the key interlayer rock group, moment of inertia, etc.), and the stress data obtained by on-site monitoring of the filling working face (the concentrated stress of the coal body after the filling working face is affected by the initial fracture of the overlying rock stratum, the overlying uniformly distributed load, and the static stress of the coal body of the filling working face) are obtained. The distance from the earthquake source of the overburden movement to the filling working face and the propagation speed of the mine shock wave are achieved through on-site monitoring, while the energy action coefficient of the mine shock, the release efficiency and attenuation coefficient of the mine shock wave are obtained through on-site exploration and monitoring.

[0047] Step S102: Determine the critical control fracture height H of the filling working surface based on the critical impact-causing key layer w. min .

[0048] After coal seam mining, the original stress balance of the surrounding rock is disrupted, causing the coal seam roof to become unstable and subject to damage such as fracture and collapse. The three-zone load theory, based on the spatiotemporal dynamics of overburden failure, considers the temporal effects of overburden movement on the stress exerted by the underlying coal mass. With the goal of controlling stress-induced disasters, it divides the overburden rock of the working face roof into immediate loading zones, delayed loading zones, and static loading zones.

[0049] The immediate loading zone, as mining progresses, will periodically flex, fracture, and collapse in the short term. This rock formation, including the immediate roof, basic roof, and the rock layers above it, can instantly fill the goaf and form a load-bearing structure. The rock layers within the immediate loading zone will undergo violent movements such as caving and rotation as mining progresses, forming a load-bearing structure. The resulting stress will manifest within the coal wall of the working face. This long-range movement of the rock layers will directly affect the impact hazard of the working face. After mining and backfilling are completed at the working face, the low-lying roof of the goaf within this rock formation will begin to bend and sink, exerting stress on the filling. The thickness of the immediate loading zone is closely related to the mining height and is equal to 10 times the equivalent mining height.

[0050] Here, the influence of time and space on the filling body is ignored, and the filling body is assumed to be the final state after pressure damage and deterioration in the stope. Therefore, the control effect of the filling body on the movement of the overlying strata can be expressed by the equivalent mining height h of the filling working face. e To express it. Specifically, according to the formula:

[0051] h e =h0k i α

[0052] Determine the equivalent mining height h of the filling working face e Where h0 is the actual mining height of the filling working face, k i is the filling rate of the filling working surface, and α is the final destruction index of the filling body of the filling working surface.

[0053] The delayed loading zone, located above the immediate loading zone, is a rock formation that is suspended during the initial mining phase but gradually delaminates and fractures over a long period of time as the load it bears exceeds its inherent strength. The stresses generated by the delayed loading zone's movement gradually manifest during the mining process and for a long period after completion, until a stable "arch" structure is formed within the internal rock formations. The movement of this rock formation exhibits temporal and spatial characteristics, with early movement dominated by collapse of lower-level rock formations adjacent to the backfill and later by delamination of higher-level rock formations. The thickness of the delayed loading zone is related to the width of the goaf.

[0054] The static load zone is the rock group located above the delayed loading zone and extending to the surface. Because it is far away from the stope, the static load zone is less affected by mining. The horizontal stress gradient of the overlying rock strata in the rock group is small, and it is considered to be uniformly loaded.

[0055] In this application, the sinking of the direct top and basic top of the overburden of the filling working face toward the goaf is simplified as the elastic bending of a flat plate or beam. On the basis of considering the settlement of the rock beam itself, except for the rock layer that is cut off as a whole, the collapse of all rock layers develops from the bending settlement movement. Therefore, when determining the height of the fracture of the overburden top plate, the influence of the settlement of the rock beam and the deformation capacity of the rock layer and the height of the lower allowable movement space must be considered.

[0056] Since the actual supporting capacity of the filling body on the overburden of the working face is limited, its ultimate control height of the overburden in the mining area can effectively represent the control of the key layer that causes impact. When the separation height formed by the sinking movement of the rock layer below the key layer is greater than the ultimate deflection of the key layer, the key layer will undergo initial fracture. The key layer that causes impact is equivalent to a double-embedded beam with a rectangular cross section and fixed at both ends. The beam deflection is taken as positive downward, the width is b, and the height is h. The bending model of the fixed-support beam under uniform load is established, as shown in the following example: Figure 3 shown.

[0057] Then, according to the formula:

[0058]

[0059] Determine the critical control fracture height H of the filling working face min Where, is the ultimate deflection of the critical impact-causing key layer w during the critical state of sinking (close to fracture but not broken, and sinking slowly due to the influence of its own weight), q w is the overlying uniformly distributed load of the critical impact-causing key layer w, l w is the overhang length of the overburden beam in the stope of the critical impact-causing key layer w, E w is the elastic modulus of the critical impact layer w, I w is the moment of inertia of the critical impact layer w; H w is the vertical distance between the roof of the critical impact-causing key layer w and the coal body of the working face.

[0060] In this application, according to the formula:

[0061]

[0062] Determine the moment of inertia I of the critical impact-causing layer w w .

[0063] Step S103: In response to the overburden movement height reaching the critical fracture state of the critical impact-causing key layer w when the filling material is filled into the filling working face, the fracture height H is controlled according to the impact-prevention critical value. min , determine the critical filling rate k for anti-collision of the filling working face.

[0064] The main purpose of backfill mining is to support the overburden in the mining area and control the dynamic load of the overburden. The control effect of the backfill on the roof of the goaf is closely related to the height of the backfill and its ability to resist compressive deformation.

[0065] After the working face completes coal mining and filling, the roof of the low-level goaf (i.e., the immediate loading zone) begins to bend and sink and exert compressive stress on the filling body. This part of the rock stratum movement will immediately appear in the coal body of the working face. When the goaf is completely filled with the low-level rock stratum (the rock stratum in the immediate loading zone), the upper rock stratum (i.e., the rock stratum in the delayed loading zone) can no longer bend, fracture, and sink in the first place due to the lack of collapse space. However, as the filling body is gradually compacted and part of the space is released, new sinking space is provided for the upper rock stratum, and the delamination and fracture of the upper rock stratum continue to expand upward until the compression deformation of the filling body no longer increases. At this time, the height H of the overburden movement after the filling working face is filled with filling material is obtained. z Specifically, according to the formula:

[0066]

[0067] Determine the overburden movement height H when filling the filling material into the filling working face z Where, K A is the instantaneous loading rock expansion coefficient, h0 is the actual mining height of the filling working face, α is the final failure index of the filling body of the filling working face, k i is the filling rate of the working surface, K i It is the comprehensive expansion coefficient of the rock group from the critical impact-causing key layer w to the coal seam.

[0068] When the overburden movement height reaches the critical fracture state of the critical impact layer w when the filling material is filled into the filling working face, the overburden movement height H Z Critical control fracture height H of anti-collision with filling working face min Equal, at this time the filling rate k of the working surface i That is the critical filling rate k for anti-collision of the filling working face.

[0069] The mechanical properties and physical parameters of the rock formation vary depending on the location of the critical impact-causing key layer w. When the critical impact-causing key layer w is in the immediate loading zone and the height of the overlying rock layer separation movement reaches the critical fracture height of the critical impact-causing key layer w, the filling material filling rate of the filling working face reaches the critical value, according to the formula:

[0070]

[0071] Determine the critical filling rate k of the backfill working face. A is the expansion coefficient of rock under instant loading, H min Critical control fracture height for anti-impact filling working face; h o is the actual mining height of the filling working face, and α is the final destruction index of the filling body of the filling working face.

[0072] When the critical impact-causing key layer w is in the delayed loading zone and the overburden stratum separation movement height reaches the critical fracture height of the critical impact-causing key layer w, the filling material filling rate of the filling working face reaches the critical value. According to the formula:

[0073]

[0074] Determine the critical filling rate k of the backfill working face. A is the expansion coefficient of rock under instant loading, H min is the critical control fracture height of the filling working face, h0 is the actual mining height of the filling working face, α is the final destruction index of the filling body of the filling working face, K i k is the comprehensive expansion coefficient of the rock group from the critical impact-causing key layer w to the coal seam; i is the filling rate of the working surface.

[0075] The support provided by the backfill on the roof depends on its fill rate: the greater the fill rate, the stronger the support and the lower the roof settlement and settlement velocity. Conversely, the smaller the fill rate, the weaker the support and the greater the roof settlement and settlement velocity. The support provided by the backfill fill rate is positively correlated with roof settlement. As the fill rate increases, the overburden strata experience a shift from complete collapse to partial collapse or no collapse. When the fill rate is high, i.e., densely filled, the overburden's critical strata are in a critical state of bending and sinking, preventing collapse. Consequently, all strata remain intact, merely bending and sinking. When the backfill working face reaches the critical fill rate, the critical strata reach their ultimate deflection and enter a state of ultimate fracture, with the overburden strata suspended over the critical strata.

[0076] When the filling rate is low, that is, in a loose filling state, the sinking space of the overburden rock key layer increases accordingly, and then breaks, and the overburden rock layer undergoes a large degree of bending and sinking. As the filling rate continues to decrease, collapse begins to occur. In a limited space, the overburden rock at different levels breaks to different degrees, and the degree is related to the distance that can be lowered and the size of the ultimate deflection. The critical filling rate strictly characterizes the movement state of the overburden rock layer, such as Figures 4 to 6 As shown in the figure, different filling rates result in different densities of the filling body, and the movement of the pile bodies in the overlying rock strata is also different.

[0077] like Figure 7 As shown, the embodiment of the present application also provides a coal mine filling working face anti-bumping critical filling rate analysis system, including:

[0078] A key layer identification unit 701 is configured to determine a critical impact-causing key layer w of the overlying strata of the filling working face;

[0079] The critical control unit 702 is configured to determine the critical control fracture height H of the filling working face based on the critical impact-causing key layer w. min ;

[0080] The filling rate unit 703 is configured to respond to the overburden movement height reaching the critical fracture state of the critical impact-causing key layer w when the filling material is filled into the filling working face, and control the fracture height H according to the impact-prevention critical min , determine the critical filling rate k for anti-collision of the filling working face.

[0081] The critical filling rate analysis system for anti-bumping of coal mine filling working faces provided in the embodiments of the present application can implement the steps and processes of the critical filling rate analysis method for anti-bumping of coal mine filling working faces of any of the above embodiments and achieve the same technical effects, which will not be repeated here.

[0082] In the description of the present invention, the terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" mean 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 invention. 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 appropriate manner in any one or more embodiments or examples.

[0083] The foregoing description is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are readily apparent to those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A method for analyzing the critical filling rate of coal mine filling working face anti-bumping, characterized in that: include: Step S101, according to the formula: Determine the critical impact-causing layer of the overlying strata at the filling working face ;in, For the filling working surface The equivalent additional disturbance stress caused by the initial breaking of the overlying rock layer on the filling working face is is the propagation speed of the mine shock wave in the filling working face, For the The energy action coefficient of the mine earthquake caused by the movement of the overlying rock layer, For the The release efficiency of mining shock waves during the movement of overlying rock layers, For the The deadweight of the overlying rock layer and the additional unit length converted load of the upper rock layer, For the The initial breaking step of the overlying rock layer, For the The suspended span of the overlying rock layer, For the The average medium density of the coal and rock mass through which the shock wave propagates; For the The attenuation coefficient of the movement of the overlying rock layer is For the The distance from the earthquake source point of the overlying rock layer movement to the filling working surface, For the The elastic modulus of the overlying rock layer, For the The thickness of the overlying rock layer; is the stress concentration factor of the filling working surface, is the static stress of the coal body at the filling working face, is the uniaxial compressive strength of the coal body at the filling working face; is the key layer causing impact of the filling working face, The key layer of the filling working face is affected by the impact Concentrated stress in coal body after the initial fracture; Step S102: Based on the critical impact key layer , determine the critical control fracture height of the filling working face ; Step S103: In response to the overburden movement height reaching the critical impact-causing key layer when the filling material is filled into the filling working face, The critical state of fracture is determined by controlling the fracture height according to the critical state of anti-impact. , determine the critical filling rate of the filling working surface .

2. The method for analyzing the critical filling rate of coal mine filling working face anti-bumping according to claim 1, characterized in that: In step S102, according to the formula: Determine the critical control fracture height of the filling working face ; in, The critical impact layer The ultimate deflection during the critical state of sinking, The critical impact layer The overlying uniform load, The critical impact layer The overhanging length of the overburden beam in the stope, The critical impact layer The elastic modulus, The critical impact layer moment of inertia; The critical impact layer The vertical distance between the roof and the coal body of the working face.

3. The method for analyzing the critical filling rate of coal mine filling working face anti-bumping according to claim 1, characterized in that: In step S103, In response to the critical impact of the key layer Located in the immediate loading zone, according to the formula: Determine the critical filling rate of the filling working surface ; in, is the expansion coefficient of the rock in the instant loading zone, Controlling the critical fracture height for anti-impact of the filling working face; is the actual mining height of the filling working face, is the final destruction index of the filling body of the filling working surface.

4. The method for analyzing the critical filling rate of coal mine filling working face anti-bumping according to claim 1, characterized in that: In step S103, In response to the critical impact of the key layer Located in the delayed loading zone, according to the formula: Determine the critical filling rate of the filling working surface ; in, is the instantaneous loading expansion coefficient of rock, The critical fracture height for anti-impact of the filling working face is controlled. is the actual mining height of the filling working face, is the final destruction index of the filling body of the filling working surface, The critical impact layer The comprehensive expansion coefficient of the rock group between coal seams.

5. A coal mine filling working face anti-bumping critical filling rate analysis system, characterized in that: The critical filling rate of the filling face for preventing blast is determined by using the method for analyzing the critical filling rate of the filling face for preventing blast according to any one of claims 1 to 4, wherein the system comprises: Key layer identification unit, configured to determine the critical impact-causing key layer of the overlying rock formation on the filling working face ; A critical control unit configured to be based on the critical impact key layer , determine the critical control fracture height of the filling working face ; The filling rate unit is configured to respond to the overburden movement height reaching the critical impact-causing key layer when the filling material is filled into the filling working face. The critical state of fracture is determined by controlling the fracture height according to the critical state of anti-impact. , determine the critical filling rate of the filling working surface .

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