A method and system for evaluating the possibility of deterioration of filling bodies in a coal mine filling working face

Abstract

This application relates to the field of coal mine safety technology, and provides a method and system for evaluating the possibility of deterioration of the filling body in a coal mine filling working face. In this method, based on the mechanical parameters of the filling body in the target filling working face, the ultimate bearing capacity of the filling body is determined; based on the overlying coal and rock parameters of the target filling working face and the layout parameters of the target filling working face, the static pressure borne by the filling body and the equivalent additional disturbance dynamic load borne by the overlying strata's initial fracture of the filling body are calculated; according to the ultimate bearing capacity, static pressure borne, and equivalent additional disturbance dynamic load of the filling body in the target filling working face, the bearing pressure deterioration index of the filling body in the target filling working face is determined to evaluate the deterioration of the filling body in the target filling working face, so as to quickly and accurately evaluate the possibility of deterioration of the filling body in the coal mine filling working face, provide precursor information for the instability of the overlying strata of the target filling working face, large-area ground subsidence, and working face impact, and ensure the efficient and safe production of the coal mine filling working face.

Description

Technical Field

[0001] The present application relates to the technical field of coal mine safety, and particularly relates to a method and system for evaluating the possibility of deterioration of a filling body in a coal mine filling working face. Background Technique

[0002] As a coal mining method that conforms to the concept of green mine construction, filling mining has the advantages of controlling the movement of overlying strata in the goaf of a coal mine, reducing ground subsidence, preventing and controlling rock bursts, and dealing with the stockpile of solid waste. However, due to the complex conditions in a coal mine underground, the limited strength of the filling body itself, and the short time interval between the filling process and the coal cutting process, the filling body in the initial setting stage is more susceptible to factors such as disturbance and pressure bearing, resulting in the deterioration of the filling body, which in turn affects the long-term service strength of the filling body underground, greatly reducing the effect of coal mine filling mining.

[0003] Therefore, there is an urgent need to provide a method and system for evaluating the possibility of deterioration of a filling body in a coal mine filling working face, so as to provide precursor information for the instability of overlying strata, large-area ground settlement, and rock bursts in the working face of the target filling, and achieve the purpose of ensuring the efficient and safe production of the coal mine filling working face. Summary of the Invention

[0004] The purpose of the present application is to provide a method and system for evaluating the possibility of deterioration of a filling body in a coal mine filling working face to solve or alleviate the problems existing in the above-mentioned prior art.

[0005] To achieve the above purpose, the present application provides the following technical solutions:

[0006] The present application provides a method for evaluating the possibility of deterioration of a filling body in a coal mine filling working face, including: Step S101, determining the ultimate bearing capacity of the filling body in the target filling working face based on the obtained mechanical parameters of the filling body in the target filling working face; Step S102, calculating the static pressure borne by the filling body in the target filling working face based on the obtained overlying coal and rock parameters of the target filling working face and the layout parameters of the target filling working face; Step S103, calculating the equivalent additional disturbance dynamic load caused by the initial fracture of the overlying strata borne by the filling body in the target filling working face; Step S104, based on the static load coupling theory, determining the bearing pressure deterioration index of the filling body in the target filling working face according to the ultimate bearing capacity, the static pressure borne, and the equivalent additional disturbance dynamic load of the filling body in the target filling working face, so as to evaluate the deterioration of the filling body in the target filling working face.

[0007] Preferably, in step S101, according to the formula:

[0008]

[0009] Determine the ultimate bearing capacity q of the filling body in the target filling working face c; where c is the cohesion of the filling body in the target filling working face is the internal friction angle of the filling body in the target filling working face

[0010] Preferably, in step S102, according to the formula:

[0011]

[0012] Determine the bearing static load of the filling body in the target filling working face when the nth layer of rock strata collapses

[0013] where V n is the volume of the nth layer of collapsed rock strata overlying the goaf in the target filling working face; ρ n is the unit weight of the nth layer of collapsed rock strata overlying the goaf in the target filling working face; S k is the area of the filling body;

[0014] S n-1 is the bottom surface area of the nth layer of collapsed rock strata overlying the goaf in the target filling working face; S 0n is the mid-section area of the nth layer of collapsed rock strata overlying the goaf in the target filling working face; S n is the top surface area of the nth layer of collapsed rock strata overlying the goaf in the target filling working face; m n is the thickness of the nth layer of collapsed rock strata overlying the goaf in the target filling working face;

[0015] L z is the strike length of the goaf in the target filling working face; H n+1 is the vertical height from the floor of the nth layer of collapsed rock strata overlying the goaf in the target filling working face to the goaf; a z is the rock strata movement angle in the strike direction of the target filling working face; L q is the dip length of the goaf in the target filling working face; α q is the rock strata movement angle in the dip direction of the target filling working face; n is a positive integer.

[0016] Preferably, in step S103, according to the formula:

[0017]

[0018] Determine the equivalent additional disturbance dynamic load of the overlying strata during the initial fracture of the (n + 1)th layer of rock strata borne by the filling body in the target filling working face

[0019] where V m is the propagation speed of the vibration wave generated by the initial fracture of the (n + 1)th layer of rock strata; p n+1is the energy action coefficient for the rock burst triggered by the movement of the (n + 1)-th layer of rock strata; η n+1 is the vibration wave release efficiency during the movement of the (n + 1)-th layer of rock strata; q n+1 is the self-weight of the (n + 1)-th layer of rock strata and the equivalent load per unit length of the overlying rock strata; L n+1 is the initial breaking step distance of the (n + 1)-th layer of rock strata; b n+1 is the hanging span of the (n + 1)-th layer of rock strata; E n+1 is the elastic modulus of the (n + 1)-th layer of rock strata; m n+1 is the thickness of the (n + 1)-th layer of rock strata;

[0020] λ n+1 is the attenuation coefficient of the vibration wave; S n+1 is the distance from the seismic source point of the initial breaking of the (n + 1)-th layer of rock strata to the target filling working face; ρ t is the average medium density of the coal and rock mass through which the vibration wave propagates.

[0021] Preferably, in step S104, according to the formula:

[0022]

[0023] determine the bearing pressure deterioration index I of the filling body of the target filling working face when the n-th layer of rock strata collapses n ;

[0024] wherein, is the equivalent additional disturbance dynamic load of the overlying rock strata initially broken borne by the filling body of the target filling working face during the initial breaking of the (n + 1)-th layer of rock strata; is the static load of the bearing pressure of the filling body of the target filling working face when the n-th layer of rock strata collapses, q c is the ultimate bearing capacity of the filling body of the target filling working face.

[0025] Preferably, the evaluation of the deterioration of the filling body of the target filling working face includes: based on a preset deterioration threshold, determining the deterioration possibility of the filling body of the target filling working face according to the bearing pressure deterioration index.

[0026] The embodiment of the present application also provides an evaluation system for the deterioration possibility of the filling body in a coal mine filling working face, including: a limit bearing unit configured to determine the ultimate bearing capacity of the filling body in the target filling working face based on the mechanical parameters of the filling body in the target filling working face obtained; a bearing static pressure unit configured to calculate the static pressure borne by the filling body in the target filling working face based on the overlying coal and rock parameters of the target filling working face and the layout parameters of the target filling working face; an equivalent disturbance unit configured to calculate the equivalent additional disturbance dynamic load of the initial breakage of the overlying strata borne by the filling body in the target filling working face; a deterioration evaluation unit configured to determine the bearing deterioration index of the filling body in the target filling working face based on the ultimate bearing capacity, the bearing static pressure, and the equivalent additional disturbance dynamic load of the filling body in the target filling working face, based on the static load coupling theory, so as to evaluate the deterioration of the filling body in the target filling working face.

[0027] Beneficial effects:

[0028] In the method for evaluating the deterioration possibility of the filling body in a coal mine filling working face provided by the embodiment of the present application, first, the ultimate bearing capacity of the filling body in the target filling working face is determined based on the mechanical parameters of the filling body in the target filling working face obtained; then, the static pressure borne by the filling body in the target filling working face is calculated based on the overlying coal and rock parameters of the target filling working face and the layout parameters of the target filling working face, and the equivalent additional disturbance dynamic load of the initial breakage of the overlying strata borne by the filling body in the target filling working face is calculated; finally, the bearing deterioration index of the filling body in the target filling working face is determined based on the static pressure borne by the filling body in the target filling working face and the equivalent additional disturbance dynamic load, based on the static load coupling theory, so as to evaluate the deterioration of the filling body in the target filling working face, so as to quickly and accurately evaluate the deterioration possibility of the filling body in the coal mine filling working face, provide precursor information for the instability of the overlying strata of the target filling working face, large-area surface subsidence, and working face impact, ensure the efficient and safe production of the coal mine filling working face, and have important practical guiding significance for the filling mining design and monitoring on the coal mine site. Description of the Drawings

[0029] The schematic diagrams in the specification forming a part of the present application are used to provide a further understanding of the present application. The schematic embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation to the present application. Among them:

[0030] Figure 1 is a schematic flow chart of a method for evaluating the deterioration possibility of the filling body in a coal mine filling working face according to some embodiments of the present application;

[0031] Figure 2 is a schematic diagram of the spatial form of the overlying strata of the filling body in the goaf of the filling working face according to some embodiments of the present application;

[0032] Figure 3Schematic structural diagram of an evaluation system for the deterioration possibility of backfill in a coal mine backfill working face provided according to some embodiments of the present application. Detailed implementation manners

[0033] 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 rather than limiting the present application. In fact, those skilled in the art will clearly understand that modifications and variations can be made to the present application without departing from the scope or spirit of the present application. For example, features shown or described as part of one embodiment can be used in another embodiment to yield yet another embodiment. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the embodiments of the present invention should fall within the scope of protection of the embodiments of the present invention.

[0034] Due to the complex conditions in the coal mine underground, the limited strength of the backfill itself, and the short time interval between the backfill process and the coal cutting process, the initial setting stage of the backfill is more vulnerable to factors such as disturbance and pressure, resulting in the deterioration (damage) of the backfill, which in turn affects the long-term service strength of the backfill underground, making the anti-impulse effect of coal mine backfill mining greatly reduced. Therefore, reasonably evaluating the possibility of backfill deterioration provides precursor information for the instability of the overlying strata of the backfill working face, large-area surface settlement, and working face impact, and can effectively ensure the efficient and safe production of the coal mine backfill working face, which has very important engineering significance for guiding on-site backfill mining.

[0035] Based on this, the present application proposes an evaluation method for the deterioration possibility of backfill in a coal mine backfill working face, as Figure 1 、 Figure 2 shown. This evaluation method includes:

[0036] Step S101: Determine the ultimate bearing capacity of the backfill in the target backfill working face based on the mechanical parameters of the backfill in the target backfill working face obtained.

[0037] The stress recovery of the gob backfill is mainly vertical stress, and the horizontal stress can be ignored, that is, the backfill is approximately in a uniaxial compression state. However, due to the differences in the size conditions of the actual underground backfill and the uniaxial compression in the laboratory, and the similarity between the backfill process and the foundation construction in geotechnical engineering, in the present application, the ultimate bearing capacity is used to characterize the stability of the backfill.

[0038] In the present application, based on the geological mining and backfill design of the target backfill working face to be backfilled, the physical and mechanical parameters (internal friction angle, cohesion, etc.) of the backfill are obtained, and according to the formula:

[0039]

[0040] Determine the ultimate bearing capacity q of the backfill in the target backfill working face c. Among them, c is the cohesion of the filling body of the target filling working face, and φ is the internal friction angle of the filling body of the target filling working face.

[0041] Step S102: Calculate the static pressure borne by the filling body of the target filling working face based on the obtained overlying coal and rock parameters of the target filling working face and the layout parameters of the target filling working face.

[0042] In this application, according to the geology and mining of the target filling working face, the parameters of each overlying rock layer of the target filling working face (elastic modulus, thickness, initial caving step distance, distance from the seismic source point of fracture to the target filling working face, etc.) and the layout parameters of the working face (working face length, working face mining height, movement angle of overlying rock layer of the working face, working face advancing footage, etc.) are obtained.

[0043] The filling body is the carrier that supports the subsidence of the overlying rock layer in the goaf of the working face. For some time after the filling body touches the roof, the main load it bears is the load of the direct roof overlying the goaf. As the mining work progresses, the overlying rock layers of the direct roof will collapse layer by layer and press on the lower rock layers, thus making the static load act on the goaf filling body. In this application, the actual bearing degree of the filling body is analyzed by establishing a mechanical model of the filling body bearing pressure.

[0044] Specifically, according to the comprehensive columnar section or borehole columnar section of the target filling working face, the heights and lithology parameters of each overlying rock layer in the goaf are obtained. Affected by the movement angle of the rock layer, the pressure-bearing rock layer of the filling body in the goaf is a frustum of a pyramid in space. Based on this, a mechanical model of the filling body bearing pressure is established:

[0045]

[0046] Among them, Pn is the static load borne by the filling body of the target filling working face when the nth layer of rock collapses, and n is a positive integer. V n is the volume of the nth layer of collapsed rock overlying the goaf of the target filling working face, ρ n is the unit weight of the nth layer of collapsed rock overlying the goaf of the target filling working face, S k is the area of the filling body, S k = z ×L q L z is the strike length of the goaf of the target filling working face, L q is the dip length of the goaf of the target filling working face.

[0047] S n-1 is the bottom surface area of the nth layer of collapsed rock overlying the goaf of the target filling working face; S 0n is the middle cross-sectional area of the nth layer of collapsed rock overlying the goaf of the target filling working face; S nis the upper top surface area of the nth caving rock stratum overlying the goaf of the target filling working face; m n is the thickness of the nth caving rock stratum overlying the goaf of the target filling working face. H n+1 is the vertical height from the floor of the nth caving rock stratum overlying the goaf of the target filling working face to the goaf; α z is the strata movement angle of the target filling working face along the strike direction; q is the strata movement angle of the target filling working face along the dip direction.

[0048] Step S103: Calculate the equivalent additional disturbance dynamic load borne by the filling body of the target filling working face.

[0049] The overlying strata of the filling stope will undergo primary breaking movement, periodic breaking movement, rotation or sliding settlement movement, and energy is released during the movement. Among them, the energy released by the primary breaking movement of the overlying strata is the largest, and the large amount of energy released by the primary breaking movement under the condition of large-scale hanging roof will affect the working face of the stope. Specifically, the mine seismic energy released by the strata movement will generate an equivalent additional disturbance stress on the working face of the stope after propagation and attenuation, and the actual disturbance to the filling body on site mainly comes from the disturbance effect caused by the dynamic load generated by the primary breaking of the overlying strata propagating to the filling body.

[0050] When the nth strata overlying the goaf collapses, it generates a static load of the nth caving rock stratum on the goaf filling body. Subsequently, the (n + 1)th stratum undergoes primary breaking movement, thereby generating a dynamic load on the target filling working face. Under the superposition effect of the dynamic load and the static load, the goaf filling body of the target filling working face deteriorates. Here, the (n + 1)th stratum that undergoes primary breaking movement is defined as the broken stratum. According to the formula:

[0051]

[0052] Determine the equivalent additional disturbance dynamic load of the primary breaking of the (n + 1)th stratum (i.e., the broken stratum) on the filling body of the target filling working face where V m is the propagation speed of the vibration wave generated by the primary breaking of the (n + 1)th stratum;

[0053] p n+1 is the energy action coefficient of the mine seismicity caused by the movement of the (n + 1)th stratum; η n+1 is the vibration wave release efficiency during the movement of the (n + 1)th stratum; q n+1 is the self-weight of the (n + 1)th stratum and the additional unit length conversion load of the overlying strata (i.e., the unit load of the overlying strata of the (n + 1)th stratum on the exposed part of the (n + 1)th stratum); L n+1 is the initial breaking step distance of the (n + 1)th stratum; b n+1 is the hanging span of the (n + 1)th stratum; En+1 is the elastic modulus of the (n + 1)-th layer of rock stratum; m n+1 is the thickness of the (n + 1)-th layer of rock stratum; λ n+1 is the attenuation coefficient of the vibration wave; S n+1 is the distance between the seismic source point of the initial fracture of the (n + 1)-th layer of rock stratum and the target filling working face; ρ t is the average medium density of the coal and rock mass through which the vibration wave propagates.

[0054] Step S104: Based on the static load coupling theory, determine the bearing pressure deterioration index of the filling body of the target filling working face according to the static pressure borne by the filling body of the target filling working face and the equivalent additional disturbance dynamic load, so as to evaluate the deterioration of the filling body of the target filling working face.

[0055] There are n layers of caving rock strata pressing on the filling body. That is, the filling body bears the static load of n layers of caving rock strata. Then, the dynamic load generated by the initial fracture of the (n + 1)-th layer of rock stratum (fractured rock stratum) acting on the filling body is the equivalent additional disturbance dynamic load borne by the filling body itself. Under the superposition effect of the dynamic load and the static load, the goaf filling body of the target filling working face deteriorates. In this application, the deterioration of the filling body of the target filling working face is evaluated based on a pre-constructed deterioration evaluation model.

[0056] Among them, the deterioration evaluation model is:

[0057]

[0058] Among them, I n is the bearing pressure deterioration index of the filling body of the target filling working face when n layers of rock strata collapse; is the equivalent additional disturbance dynamic load on the filling body of the target filling working face when the (n + 1)-th layer of rock stratum initially fractures, is the bearing static load of the filling body of the target filling working face when the n-th layer of rock stratum collapses, q c is the ultimate bearing capacity of the filling body of the target filling working face.

[0059] In this application, the bearing pressure deterioration index I n has a proportional relationship with the effectiveness possibility of the filling body of the target filling working face. Again, based on a preset deterioration threshold, according to the bearing pressure deterioration index I n , determine the deterioration possibility of the filling body of the target filling working face. Specifically, when I n ∈[1, 1.5), the filling body of the target filling working face has a weak deterioration possibility, and it is necessary to strengthen the monitoring of the displacement of the overlying roof of the filling body in the goaf and the microseismic monitoring of the stope; when I n ∈[1.5, 2), the filling body of the target filling working face has a medium deterioration possibility, and it is necessary to strengthen the monitoring of the displacement of the overlying roof of the filling body in the goaf and the microseismic monitoring of the stope, and improve the ultimate bearing capacity of the filling body; when I nWhen ∈[2, +∞), the backfill in the target backfill working face has a strong possibility of deterioration. On the basis of strengthening the displacement monitoring of the overlying roof of the backfill in the goaf and the microseismic monitoring of the stope, and improving the ultimate bearing capacity of the backfill, the integrity of the thick and hard key strata in the overlying strata is damaged by means of roof blasting to eliminate the dynamic load source in advance.

[0060] Therefore, according to the bearing deterioration index of the backfill in the target backfill working face, the deterioration of the backfill in the target backfill working face is evaluated to quickly and accurately evaluate the possibility of deterioration of the backfill in the coal mine backfill working face, providing precursor information for the instability of the overlying strata, large-area surface subsidence and working face impact in the target backfill working face, ensuring the efficient and safe production of the coal mine backfill working face, and having important practical guiding significance for the design and monitoring of the on-site backfill mining in the coal mine.

[0061] As Figure 3 shown, the embodiment of the present application also provides a system for evaluating the possibility of deterioration of the backfill in a coal mine backfill working face, including:

[0062] The ultimate bearing unit 301 is configured to give the mechanical parameters of the backfill of the target backfill working face obtained, and determine the ultimate bearing capacity of the backfill of the target backfill working face;

[0063] The bearing static pressure unit 302 is configured to calculate the bearing static pressure of the backfill of the target backfill working face based on the overlying coal and rock parameters of the target backfill working face obtained and the layout parameters of the target backfill working face;

[0064] The equivalent disturbance unit 303 is configured to calculate the equivalent additional disturbance dynamic load of the initial fracture of the overlying strata borne by the backfill of the target backfill working face;

[0065] The deterioration evaluation unit 304 is configured to determine the bearing deterioration index of the backfill of the target backfill working face according to the ultimate bearing capacity, bearing static pressure and equivalent additional disturbance dynamic load of the backfill of the target backfill working face, and based on the static load coupling theory, so as to evaluate the deterioration of the backfill of the target backfill working face.

[0066] The system for evaluating the possibility of deterioration of the backfill in the coal mine backfill working face provided by the embodiment of the present application can implement the steps and processes of the method for evaluating the possibility of deterioration of the backfill in the coal mine backfill working face described in any of the above embodiments, and achieve the same technical effects, which will not be repeated here one by one.

[0067] In the description of the present invention, unless otherwise explicitly specified and defined, the first feature being "on" or "under" the second feature may mean that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "beneath" and "underneath" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply indicates that the horizontal height of the first feature is less than that of the second feature.

[0068] In the present invention, the terms "an embodiment", "some embodiments", "examples", "specific examples", or "some examples", etc. mean that the specific features, structures, materials, or characteristics described in connection 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 one or more embodiments or examples in a suitable manner.

[0069] The foregoing are only the preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, various modifications and variations can be made to the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included within the protection scope of the present application.

Claims

1. A method for evaluating the possibility of deterioration of filling bodies in a coal mine filling working face, characterized in that, Including: Step S101: Based on the mechanical parameters of the filling body of the target filling working face obtained, determine the ultimate bearing capacity of the filling body of the target filling working face; Step S102: Based on the overlying coal and rock parameters of the target filling working face obtained and the layout parameters of the target filling working face, calculate the static pressure borne by the filling body of the target filling working face; Wherein, according to the formula: ； Determine the bearing static pressure of the filling body in the target filling working face when the rock stratum of the ; Among them, is the volume of the caving rock strata in the overlying layer of the goaf of the target filling working face; is the bulk density of the caving rock strata in the overlying layer of the goaf of the target filling working face; is the area of the filling body; is the bottom surface area of the caving rock stratum overlying the goaf of the target filling working face ; is the mid-section area of the caving rock stratum overlying the goaf of the target filling working face ; is the top surface area of the caving rock stratum overlying the goaf of the target filling working face ; is the thickness of the caving rock stratum overlying the goaf of the target filling working face ; is the strike length of the gob area of the target filling working face; is the vertical height from the floor of the caving strata above the gob area of the target filling working face to the gob area for the th layer; is the strata movement angle of the target filling working face along the strike direction; is the dip length of the gob area of the target filling working face; is the strata movement angle of the target filling working face along the dip direction; are all positive integers, is the total number of caving strata overlying the gob area of the target filling working face; Step S103: Calculate the equivalent additional disturbance dynamic load of the initial fracture of the overlying rock borne by the filling body of the target filling working face; Step S104: Based on the ultimate bearing capacity, the static pressure borne, and the equivalent additional disturbance dynamic load of the filling body of the target filling working face, and based on the static load coupling theory, determine the bearing pressure deterioration index of the filling body of the target filling working face to evaluate the deterioration of the filling body of the target filling working face.

2. The evaluation method for the possibility of deterioration of the filling body in a coal mine filling working face according to claim 1, characterized in that In step S101, According to the formula: ； Determine the ultimate bearing capacity of the filling body in the target filling working face ; Among them, is the cohesion of the filling body of the target filling working face; is the internal friction angle of the filling body of the target filling working face.

3. The evaluation method for the possibility of deterioration of the filling body in a coal mine filling working face according to claim 1, characterized in that In step S103, According to the formula: ； Determine the equivalent additional disturbance dynamic load of the first break of overlying strata borne by the filling body of the target filling working face when the strata of the ; Among them, is the propagation speed of the vibration wave generated by the initial fracture of the -th layer of rock stratum; is the energy action coefficient of the mine tremor caused by the movement of the -th layer of rock stratum; is the vibration wave release efficiency during the movement of the -th layer of rock stratum; is the self-weight of the -th layer of rock stratum and the additional unit length converted load of the overlying rock stratum; is the initial fracture step distance of the -th layer of rock stratum; is the suspended span of the -th layer of rock stratum; is the elastic modulus of the -th layer of rock stratum; is the thickness of the -th layer of rock stratum; is the attenuation coefficient of the vibration wave; is the distance from the seismic source point of the initial fracture of the [[layer number]]-th layer of rock stratum to the target filling working face; is the average medium density of the coal and rock mass through which the vibration wave propagates.

4. The evaluation method for the possibility of deterioration of the filling body in the coal mine filling working face according to claim 1, characterized in that, In step S104, According to the formula: ； Determine The bearing pressure deterioration index of the filling body in the target filling working face when the strata collapse ; Among them, is the equivalent additional disturbance dynamic load of the overlying strata's initial fracture borne by the filling body of the target filling working face when the -th layer of rock strata undergoes initial fracture; is the static load borne by the filling body of the target filling working face when the -th layer of rock strata collapses, and is the ultimate bearing capacity of the filling body of the target filling working face.

5. The method for evaluating the possibility of deterioration of the filling body in a coal mine filling working face according to claim 4, wherein The evaluation of the deterioration of the filling body of the target filling working face includes: Based on a preset deterioration threshold, determine the deterioration possibility of the filling body of the target filling working face according to the bearing pressure deterioration index.

6. An evaluation system for the possibility of deterioration of the filling body in a coal mine filling working face, characterized in that, Including: Ultimate bearing unit, configured to determine the ultimate bearing capacity of the filling body of the target filling working face based on the mechanical parameters of the filling body of the target filling working face obtained; Static pressure bearing unit, configured to calculate the static pressure borne by the filling body of the target filling working face based on the overlying coal and rock parameters of the target filling working face obtained and the layout parameters of the target filling working face; Wherein, according to the formula: ； Determine the bearing static pressure of the filling body in the target filling working face when the rock strata of the ; Among them, is the volume of the caving strata of the layer overlying the gob area of the target filling working face; is the bulk density of the caving strata of the layer overlying the gob area of the target filling working face; is the area of the filling body; is the bottom surface area of the caving strata overlying the goaf of the target filling working face; is the mid-section area of the caving strata overlying the goaf of the target filling working face; is the top surface area of the caving strata overlying the goaf of the target filling working face; is the thickness of the caving strata overlying the goaf of the target filling working face; ​​​​ is the strike length of the gob area of the target filling working face; is the vertical height from the floor of the caving strata of the th layer overlying the gob area of the target filling working face to the gob area; is the strata movement angle of the target filling working face along the strike direction; is the dip length of the gob area of the target filling working face; is the strata movement angle of the target filling working face along the dip direction; All are positive integers, is the total number of caving strata overlying the goaf of the target filling working face; Equivalent disturbance unit, configured to calculate the equivalent additional disturbance dynamic load of the initial fracture of the overlying rock borne by the filling body of the target filling working face; Deterioration evaluation unit, configured to determine the bearing pressure deterioration index of the filling body of the target filling working face based on the ultimate bearing capacity, the static pressure borne, and the equivalent additional disturbance dynamic load of the filling body of the target filling working face, and based on the static load coupling theory, to evaluate the deterioration of the filling body of the target filling working face.

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