Method and device for determining three vertical zones in overlying strata

Abstract

The invention discloses a method and a device for determining three vertical zones in overlying strata. The method comprises the steps that mechanical characteristic information and geological characteristic information corresponding to overlying strata above a coal seam are obtained, the mechanical characteristic information is used for representing the stability degree of the overlying strata under the action of different forces, and the geological characteristic information is used for representing the stability degree of the structure of the overlying strata; based on the mechanical feature information and the geological feature information, accumulated loads corresponding to multiple sub-strata in the overlying strata are determined, and based on the accumulated loads, at least one initial sub-strata is screened out of the multiple sub-strata; determining a fracture step pitch of the at least one initial sub-rock stratum at least based on the cumulative load, and determining a target sub-rock stratum from the at least one initial sub-rock stratum based on the fracture step pitch; and detecting the target substrata to obtain a detection result, and determining three vertical zones from the target substrata based on the detection result. The method solves the technical problem of low determination accuracy of the three vertical zones in the overlying strata.

Description

Technical Field

[0001] The invention relates to the technical field of coal mining, and in particular to a method and device for determining three vertical zones in overburden. Background Art

[0002] At present, in the process of coal seam mining, the disturbance caused by the force generated by mining on the structure of the overburden on the coal seam is inevitable. As the coal seam is mined, the overburden will undergo changes such as bending, fracture and collapse under the action of gravity, and eventually form a vertical three-band structure in the overburden above the coal seam currently being mined. Therefore, how to predict whether the vertical three-band is generated is crucial to guiding the rock control and hydrogeological support work in coal mining.

[0003] In the related art, the three vertical zones are usually determined by combining empirical formulas, theoretical models and field observation data. Empirical formulas and theoretical models are often based on simplified assumptions and may not accurately reflect the response of rock formations under complex geological conditions, especially in the special case of overlapping mining of shallow buried coal seams. The field observation data method requires a large amount of field data on rock formations and mining conditions, but in some cases, the above field data may be difficult to obtain or insufficient, affecting the accuracy of the prediction. Therefore, there is still a technical problem of low accuracy in determining the three vertical zones in the overburden.

[0004] Currently, no effective solution has been proposed for the above technical problems. Summary of the invention

[0005] The embodiments of the present invention provide a method and device for determining three vertical zones in overburden, so as to at least solve the technical problem of low accuracy in determining three vertical zones in overburden.

[0006] According to one aspect of an embodiment of the present invention, a method for determining three vertical zones in an overburden is provided. The method may include: obtaining mechanical characteristic information and geological characteristic information corresponding to the overburden above the coal seam, wherein the mechanical characteristic information is used to indicate the stability of the overburden under the action of different forces, and the geological characteristic information is used to indicate the stability of the structure of the overburden; based on the mechanical characteristic information and the geological characteristic information, respectively determining the cumulative loads corresponding to multiple sub-rock layers in the overburden, and based on the cumulative loads, screening out at least one initial sub-rock layer from the multiple sub-rock layers, wherein the initial sub-rock layer is a sub-rock layer whose cumulative load meets a cumulative load threshold among the multiple sub-rock layers; at least based on the cumulative load, determining the fracture step distance of at least one initial sub-rock layer, and based on the fracture step distance, determining a target sub-rock layer from the at least one initial sub-rock layer, wherein the fracture step distance of the target sub-rock layer meets the fracture step distance threshold; detecting the target sub-rock layer to obtain a detection result, and based on the detection result, determining three vertical zones from the target sub-rock layer, wherein the detection result is used to indicate whether the target sub-rock layer is in a fractured state, and the three vertical zones include a collapse zone, a fracture zone, and a curved subsidence zone.

[0007] Optionally, the mechanical characteristic information includes at least the elastic modulus of the overburden, and the geological characteristic information includes at least the thickness, weight and volume of the overburden, wherein the cumulative loads corresponding to multiple sub-rock layers in the overburden are determined based on the mechanical characteristic information and the geological characteristic information, including: according to the arrangement order of the multiple sub-rock layers in the overburden, the cumulative loads of the sub-rock layers are determined based on the elastic modulus, thickness, weight and volume corresponding to different sub-rock layers.

[0008] Optionally, the cumulative load threshold is the cumulative load of the next sub-rock layer of the sub-rock layer, wherein based on the cumulative load, at least one initial sub-rock layer is screened out from multiple sub-rock layers, including: in response to the cumulative load of the sub-rock layer being greater than the cumulative load of the next sub-rock layer of the sub-rock layer, determining that the sub-rock layer is the initial sub-rock layer; the method also includes: in response to the cumulative load of the sub-rock layer being less than or equal to the cumulative load threshold, determining that the sub-rock layer is not the initial sub-rock layer.

[0009] Optionally, the mechanical characteristic information also includes tensile strength, wherein the fracture step distance of at least one initial sub-rock layer is determined based at least on the cumulative load, including: determining the fracture step distance based on the thickness, tensile strength and cumulative load of the initial sub-rock layer.

[0010] Optionally, in response to there being multiple initial sub-rock layers, the fracture step threshold is the fracture step of each initial sub-rock layer below the initial sub-rock layer, or the fracture step of the initial sub-rock layer above the initial sub-rock layer, wherein a target sub-rock layer is determined from at least one initial sub-rock layer, including: in response to the fracture step of the initial sub-rock layer being greater than the fracture step of each initial sub-rock layer below the initial sub-rock layer, the initial sub-rock layer is determined to be the target sub-rock layer; in response to the fracture step of the initial sub-rock layer being less than the fracture step of the initial sub-rock layer above the initial sub-rock layer, the initial sub-rock layer and the initial sub-rock layer above the initial sub-rock layer are determined to be the target sub-rock layer.

[0011] Optionally, the detection results include a first detection result, a second detection result and a third detection result, the first detection result is used to determine a bending subsidence zone, the second detection result is used to determine a fault zone, and the third detection result is used to determine a collapse zone, wherein the target sub-rock layer is detected to obtain the detection results, including: obtaining the lower delamination space corresponding to the target sub-rock layer, and determining the first detection result based on the lower delamination space and the maximum bending subsidence vertical deformation; determining the second detection result based on the lower delamination space and the extreme instability settlement corresponding to the target sub-rock layer; determining the settlement distance corresponding to the target sub-rock layer based on the lower delamination space; determining the rotation angle data of the key block after the target sub-rock layer is fractured based on the settlement distance; determining the third detection result based on the rotation angle data, the maximum rotation angle data and the blockiness data of the key block.

[0012] Optionally, obtaining the lower delamination space corresponding to the target sub-rock layer includes: determining the lower delamination space based on the recovery rate of the coal seam corresponding to the target sub-rock layer, the thickness of the coal seam, and the total thickness of the sub-rock layer below the target sub-rock layer; before determining the first detection result based on the lower delamination space and the maximum bending and sinking vertical deformation, the method also includes: determining the maximum bending and sinking vertical deformation based on the cumulative load, elastic modulus and thickness of the target sub-rock layer; determining the first detection result based on the lower delamination space and the maximum bending and sinking vertical deformation, including: in response to the lower delamination space being greater than or equal to the maximum bending and sinking vertical deformation, determining that the detection result is that the target sub-rock layer is in a fractured state; based on the first detection result, determining three vertical zones from the target sub-rock layer, including: in response to the lower delamination space being less than the maximum bending and sinking vertical deformation, determining the first detection result is that the target sub-rock layer is not in a fractured state, and determining the target sub-rock layer and the sub-rock layer above the target sub-rock layer as a bending and sinking zone.

[0013] Optionally, the extreme instability settlement amount includes a first extreme instability settlement amount and a second extreme instability settlement amount, the first extreme instability settlement amount being less than the second extreme instability settlement amount, wherein, based on the lower delamination space and the extreme instability settlement amount corresponding to the target sub-rock layer, a second detection result is determined, including: in response to the lower delamination space being greater than or equal to the first extreme instability settlement amount, and the lower delamination space being less than or equal to the second extreme instability settlement amount, determining that the second detection result is that the target sub-rock layer is in a fractured state; based on the second detection result, determining three vertical zones from the target sub-rock layer, including: in response to the lower delamination space being greater than or equal to the first extreme instability settlement amount, and the lower delamination space being less than or equal to the second extreme instability settlement amount, determining the target sub-rock layer and the sub-rock layer above the target sub-rock layer as fracture zones.

[0014] Optionally, based on the rotation angle data, the maximum rotation angle data and the block size data of the key block, a third detection result is determined, including: based on the rotation angle data and the maximum rotation angle data, determining a block size threshold of the block size; in response to the block size being less than or equal to the block size threshold, determining the third detection result; based on the third detection result, determining three vertical zones from the target sub-rock layer, including: in response to the block size being less than or equal to the block size threshold, determining the target sub-rock layer and the sub-rock layer above the target sub-rock layer as collapse zones.

[0015] According to another aspect of an embodiment of the present invention, a device for determining three vertical zones in overburden is also provided. The device may include: an acquisition unit, used to acquire mechanical characteristic information and geological characteristic information corresponding to the overburden above the coal seam, wherein the mechanical characteristic information is used to indicate the stability of the overburden under the action of different forces, and the geological characteristic information is used to indicate the stability of the structure of the overburden; a first determination unit, used to determine the cumulative loads corresponding to multiple sub-rock layers in the overburden based on the mechanical characteristic information and the geological characteristic information, and based on the cumulative loads, select at least one initial sub-rock layer from the multiple sub-rock layers, wherein the initial sub-rock layer is the sub-rock layer whose cumulative load satisfies the cumulative load among the multiple sub-rock layers; a sub-rock layer with a load threshold; a second determining unit, for determining a fracture step distance of at least one initial sub-rock layer at least based on the cumulative load, and determining a target sub-rock layer from the at least one initial sub-rock layer based on the fracture step distance, wherein the fracture step distance of the target sub-rock layer satisfies the fracture step distance threshold; a third determining unit, for detecting the target sub-rock layer, obtaining a detection result, and determining three vertical zones from the target sub-rock layer based on the detection result, wherein the detection result is used to indicate whether the target sub-rock layer is in a fractured state, and the three vertical zones include a collapse zone, a fracture zone, and a curved subsidence zone.

[0016] According to another aspect of an embodiment of the present invention, a computer-readable storage medium is also provided. The computer-readable storage medium includes a stored program, wherein when the program is executed, the device where the computer-readable storage medium is located is controlled to execute the method for determining three vertical zones in overburden according to an embodiment of the present invention.

[0017] According to another aspect of an embodiment of the present invention, a processor is provided, which is used to run a program, wherein when the program is run, the method for determining three vertical zones in overburden according to an embodiment of the present invention is executed.

[0018] According to another aspect of the embodiments of the present invention, a computer program product is provided, which includes a computer program, and when the computer program is executed by a processor, the method for determining three vertical zones in overburden in the embodiment of the present application is implemented.

[0019] In an embodiment of the present invention, if the three vertical zones in the overburden are to be determined, the mechanical characteristic information and geological characteristic information corresponding to the overburden above the coal seam can be obtained; based on the mechanical characteristic information and the geological characteristic information, the cumulative loads corresponding to the multiple sub-rock layers in the overburden are determined respectively, and based on the cumulative loads, at least one initial sub-rock layer is screened out from the multiple sub-rock layers; at least based on the cumulative load, the fracture step of at least one initial sub-rock layer is determined, and based on the fracture step, the target sub-rock layer is determined from the at least one initial sub-rock layer; the target sub-rock layer is detected to obtain the detection result, and based on the detection result, the three vertical zones are determined from the target sub-rock layer. In this embodiment, the target sub-rock layer (key layer) is determined by screening the sub-rock layers twice. The first time, the cumulative load is determined to screen out the initial sub-rock layer, which is more comprehensive than the empirical method. The second time, the fracture step of different initial sub-rock layers and the corresponding fracture step threshold are compared to screen out the key layer that is prone to produce the three vertical zones. By evaluating whether the key layer is in a fractured state, it is possible to determine whether three vertical zones are generated in the key layer, and accurately determine whether it is a fracture zone, a collapse zone or a curved subsidence zone, making the determination of the three vertical zones more comprehensive and objective, thereby achieving the technical effect of improving the accuracy of determining the three vertical zones in the overburden rock, and solving the technical problem of low accuracy in determining the three vertical zones in the overburden rock. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0021] Figure 1 is a flow chart of a method for determining three vertical zones in overburden according to an embodiment of the present invention;

[0022] Figure 2It is a flow chart of a method for determining three vertical zones of overlapping disturbed overburden in a shallow buried coal seam group according to an embodiment of the present invention;

[0023] Figure 3 is a schematic diagram of three vertical zones division of coal seam mining according to an embodiment of the present invention;

[0024] Figure 4 is a schematic diagram of a device for determining three vertical zones in overburden according to an embodiment of the present invention. DETAILED DESCRIPTION

[0025] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0026] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0027] According to an embodiment of the present invention, an embodiment of a method for determining three vertical zones in overburden is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in an order different from that shown here.

[0028] Figure 1 is a flow chart of a method for determining three vertical zones in overburden according to an embodiment of the present invention. Figure 1 As shown, the method may include the following steps:

[0029] Step S102, obtaining mechanical characteristic information and geological characteristic information corresponding to the overburden above the coal seam.

[0030] In the technical solution provided in the above step S102 of the present invention, the mechanical characteristic information can be used to indicate the stability of the overburden under the action of different forces. The mechanical characteristic information can be compressive strength, tensile strength, elastic modulus, Poisson's ratio, etc. The geological characteristic information is used to indicate the stability of the structure of the overburden. The geological characteristic information can be thickness, occurrence (i.e., the inclination angle and direction of the rock layer), bulk density, etc.

[0031] In this embodiment, if it is necessary to monitor whether the coal seam mining process will encounter danger, the mechanical characteristic information and geological characteristic information corresponding to the overburden above the coal seam being mined can be obtained.

[0032] Optionally, if the compressive strength or thickness of the overburden is too small during coal seam mining, the risk of mining will increase. Especially in the mining process of shallow buried coal seams, the thickness of the overburden is small. If the compressive strength and other information are also low, the overburden is more susceptible to mining disturbances, and will break, slide and collapse, thereby increasing the risk of mining. Therefore, how to monitor the mechanical characteristic information and address characteristic information of the overburden above the coal seam in real time during the mining process to further determine the three vertical zones is particularly important for avoiding danger to personnel during the mining process. That is, obtaining the mechanical characteristic information and geological characteristic information of the overburden above the coal seam during mining can ensure the stability and safety of the mining process.

[0033] For example, the compressive strength of the mechanical characteristic information corresponding to the overburden above the coal seam can be obtained through core sampling, rock mechanics experiments, geological surveys, etc. The thickness of the geological characteristic information corresponding to the overburden above the coal seam can be obtained through geological exploration methods such as geological profiles, geological drilling, and seismic exploration.

[0034] It should be noted that the above-mentioned method of obtaining the mechanical characteristic information and geological characteristic information corresponding to the overburden above the coal seam is only for illustration and is not specifically limited here. As long as the information can be used to measure the compressive resistance of the overburden under different forces and the specific structure of the overburden, and the corresponding acquisition method, they are all within the protection scope of the embodiments of the present invention.

[0035] Step S104, based on the mechanical characteristic information and the geological characteristic information, respectively determine the cumulative loads corresponding to the multiple sub-rock layers in the overburden, and based on the cumulative loads, select at least one initial sub-rock layer from the multiple sub-rock layers.

[0036] In the technical solution provided in the above step S104 of the present invention, after obtaining the mechanical characteristic information and geological characteristic information corresponding to the overburden above the coal seam, the cumulative load corresponding to each sub-rock layer in the overburden can be determined based on the mechanical characteristic information and the geological characteristic information, and at least one initial sub-rock layer can be selected from multiple sub-rock layers based on the cumulative load. The sub-rock layer can be any rock layer in the overburden above the coal seam in the coal mine. The initial sub-rock layer can be a sub-rock layer whose cumulative load meets the cumulative load threshold among multiple sub-rock layers, and can also be called a hard rock layer.

[0037] Optionally, the cumulative load can be used to reflect the pressure superposition of the overburden layer on the overburden layer below it, which is an important basis for judging the fracture tendency of the rock layer. The cumulative load threshold can be used to screen out sub-rock layers (initial sub-rock layers) that may be sensitive to mining disturbances or play an important role in the overburden structure.

[0038] Optionally, the cumulative load threshold may be set based on a comprehensive consideration of the mechanical and geological characteristics of the overburden, and an assessment of the load that the rock layer may bear. The cumulative load threshold may be pre-set, for example, the sum of the previous cumulative loads of the overburden layer below the current overburden layer, or may be pre-set based on rules such as empirical formulas or guidelines for rock type, mining depth, or geological pressure, which are only for illustration and are not specifically limited here.

[0039] In this embodiment, based on the collected mechanical characteristic information and geological characteristic information, the rock mechanics theory can be used to calculate the cumulative loads corresponding to multiple sub-rock layers in the overburden. By comparing the magnitude relationship between the cumulative loads of each sub-rock layer and the cumulative load threshold, at least one initial sub-rock layer with a cumulative load higher than the threshold can be screened out from multiple sub-rock layers, so that the deformation and damage of the overburden can be judged in advance, possible safety hazards can be predicted, and effective prevention and control measures can be taken to ensure the safe operation of coal mine production.

[0040] Step S106, determining a fracture step distance of at least one initial sub-rock layer based at least on the accumulated load, and determining a target sub-rock layer from the at least one initial sub-rock layer based on the fracture step distance.

[0041] In the technical solution of step S106 of the present invention, after at least one initial sub-rock layer is screened out from multiple sub-rock layers based on the cumulative load, the fracture step of at least one initial sub-rock layer can be determined based at least on the cumulative load, and the target sub-rock layer can be determined from at least one initial sub-rock layer based on the fracture step. Among them, the fracture step of the target sub-rock layer meets the fracture step threshold. The target sub-rock layer can be a key layer. The fracture step is the distance or number of steps from the beginning of deformation to the occurrence of fracture damage under the action of force on the overburden, which can be used to describe the stability and fracture characteristics of the overburden, and is closely related to the mechanical characteristic information corresponding to the overburden above the coal seam and the cumulative load. The fracture step threshold can be used to identify which sub-rock layers may become key layers or potential key layers after mining disturbance, thereby affecting the stability of the overburden and the development of the fracture zone. The setting of the fracture step threshold can be based on a comprehensive consideration of the mechanical characteristics, geological characteristics and mining conditions corresponding to the overlying rock above the coal seam. For example, it can be the fracture step of each initial sub-rock layer below the current initial sub-rock layer. It should be noted that the size of the above-mentioned fracture step threshold is only for example and is not specifically limited here.

[0042] In this embodiment, if the fracture step of the initial sub-rock layer meets the fracture step threshold, the initial sub-rock layer at this time can be regarded as the target sub-rock layer, that is, the key layer. Accurate identification of the target sub-rock layer can predict the stability and potential fracture of the overburden in advance, adjust the mining strategy in real time, enhance the controllability of the mining process, and predict the position and height of the three vertical zones of the overburden, providing a basis for safety measures and risk assessment of coal mining projects, and reducing interruptions and accident losses during the mining process.

[0043] Step S108, detecting the target sub-rock layer to obtain a detection result, and based on the detection result, determining three vertical zones from the target sub-rock layer.

[0044] In the technical solution provided in the above step S108 of the present invention, after determining the target sub-rock layer from at least one initial sub-rock layer, the target sub-rock layer can be detected to obtain the detection result, and based on the detection result, the three vertical zones can be determined from the target sub-rock layer. Among them, the detection result is used to indicate whether the target sub-rock layer is in a fractured state. The three vertical zones may include a collapse zone, a fault zone, and a curved sinking zone. A collapse zone refers to a rock layer area where the rock layer completely collapses after mining disturbance, the rock mass loses its original structure, and forms a loose or broken state. A fault zone is an area where the target sub-rock layer reaches or exceeds the fracture step threshold under mining disturbance, the rock layer cracks and connects into a belt, but the rock mass still maintains a certain structural strength. A curved sinking zone refers to an area where the overburden does not reach a fractured state under mining disturbance, the rock layer shows elastic deformation and bending sinking, and this part of the rock layer is relatively stable and the degree of crack development is low.

[0045] Optionally, in the process of detecting the key layer, the separation space below the key layer (that is, the space away from the coal seam) and the relevant parameters of the key blocks formed by the key layer being in a fractured state (for example, thickness, etc.) can be detected to obtain corresponding detection results. That is, detecting the key layer through the above process can not only be used to determine whether the target sub-rock layer is in a fractured state, but also can further determine the vertical three zones.

[0046] Optionally, the state of the target sub-rock layer can be detected by ground and underground geological radar, microseismic monitoring, acoustic emission technology, core analysis, seismic wave reflection and other methods, which are only for example and are not specifically limited here. As long as the method can be used to detect whether the target sub-rock layer is in a fractured state, it is within the protection scope of the embodiment of the present invention.

[0047] In the above steps S102 to S108 of the present application, if the three vertical zones in the overburden are to be determined, the mechanical characteristic information and geological characteristic information corresponding to the overburden above the coal seam can be obtained; based on the mechanical characteristic information and geological characteristic information, the cumulative loads corresponding to the multiple sub-rock layers in the overburden are determined respectively, and based on the cumulative loads, at least one initial sub-rock layer is screened out from the multiple sub-rock layers; at least based on the cumulative load, the fracture step of at least one initial sub-rock layer is determined, and based on the fracture step, the target sub-rock layer is determined from the at least one initial sub-rock layer; the target sub-rock layer is detected to obtain the detection result, and based on the detection result, the vertical three zones are determined from the target sub-rock layer. In this embodiment, the target sub-rock layer (key layer) is determined by screening the sub-rock layers twice, and the cumulative load is determined for the first time to screen out the initial sub-rock layer, which is more comprehensive than the empirical method. The second time, the fracture step of different initial sub-rock layers and the corresponding fracture step threshold are compared to screen out the key layer that is easy to produce the three vertical zones. By evaluating whether the key layer is in a fractured state, it is possible to determine whether three vertical zones are generated in the key layer, and accurately determine whether it is a fracture zone, a collapse zone or a curved subsidence zone, making the determination of the three vertical zones more comprehensive and objective, thereby achieving the technical effect of improving the accuracy of determining the three vertical zones in the overburden rock, and solving the technical problem of low accuracy in determining the three vertical zones in the overburden rock.

[0048] The above method of this embodiment is further introduced below.

[0049] As an optional implementation method, the mechanical characteristic information includes at least the elastic modulus of the overburden, and the geological characteristic information includes at least the thickness, weight and volume of the overburden, wherein step S104, based on the mechanical characteristic information and the geological characteristic information, respectively determines the cumulative loads corresponding to multiple sub-rock layers in the overburden, including: according to the arrangement order corresponding to the multiple sub-rock layers in the overburden, the cumulative loads of the sub-rock layers are determined based on the elastic modulus, thickness, weight and volume corresponding to different sub-rock layers.

[0050] In this embodiment, in the process of determining the cumulative loads corresponding to multiple sub-rock layers in the overburden based on the mechanical characteristic information and the geological characteristic information, the cumulative loads of the sub-rock layers can be determined based on the elastic modulus, thickness, weight and volume corresponding to different sub-rock layers in accordance with the arrangement order of the multiple sub-rock layers in the overburden. Among them, the mechanical characteristic information at least includes the elastic modulus of the overburden, and the geological characteristic information at least includes the thickness, weight and volume of the overburden. The arrangement order can be from top to bottom, which is only for illustration here and is not specifically limited.

[0051] Alternatively, the cumulative load on the formation can be determined by the following formula:

[0052]

[0053] Among them, q n It can be used to represent the cumulative load of the rock formation, with the unit of N; E can be used to represent the elastic modulus, for example, E i It can be used to represent the elastic modulus of the i-th rock layer in GPa; h can be used to represent the thickness of the rock layer, for example, h i It can be used to indicate the thickness of the j-th rock layer, in meters.

[0054]

[0055] Among them, W n Can be used to indicate the weight of rock formation, the unit is KN; V n Can be used to express the volume of rock formations in m 3 .

[0056] As an optional implementation manner, the cumulative load threshold is the cumulative load of the next sub-rock layer of the sub-rock layer, wherein based on the cumulative load, at least one initial sub-rock layer is screened out from multiple sub-rock layers, including: in response to the cumulative load of the sub-rock layer being greater than the cumulative load of the next sub-rock layer of the sub-rock layer, determining that the sub-rock layer is the initial sub-rock layer; the method also includes: in response to the cumulative load of the sub-rock layer being less than or equal to the cumulative load threshold, determining that the sub-rock layer is not the initial sub-rock layer.

[0057] In this embodiment, in the process of selecting at least one initial sub-rock layer from multiple sub-rock layers based on the cumulative load, the sub-rock layer may be determined to be the initial sub-rock layer if the cumulative load of the sub-rock layer is greater than the cumulative load of the next sub-rock layer of the sub-rock layer. If the cumulative load of the sub-rock layer is less than or equal to the cumulative load threshold, the sub-rock layer is determined not to be the initial sub-rock layer.

[0058] Optionally, the next sub-layer of the sub-layer, that is, layer n+1, the cumulative load of layer n+1 can be expressed as q n+1The cumulative load of each sub-layer can be calculated from top to bottom, and the cumulative load q of the nth layer is taken as n The cumulative load q of the n+1 layer n+1 By comparison, it can be determined whether the sub-layer is the initial sub-layer.

[0059] Optionally, if the cumulative load of a sub-layer is greater than the cumulative load of the next sub-layer of the sub-layer, that is, q n >q n+1 , we can determine that the nth layer is a hard rock layer. If the cumulative load of the sub-rock layer is less than or equal to the cumulative load threshold, that is, q n ≤q n+1 , then it cannot be determined that the nth layer is a hard rock layer.

[0060] As an optional implementation method, the mechanical characteristic information also includes tensile strength, wherein step S106, at least based on the cumulative load, determines the fracture step of at least one initial sub-rock layer, including: determining the fracture step based on the thickness, tensile strength and cumulative load of the initial sub-rock layer.

[0061] In this embodiment, in the process of determining the fracture step length of at least one initial sub-rock layer based at least on the cumulative load, the fracture step length may be determined based on the thickness, tensile strength and cumulative load of the initial sub-rock layer, wherein the mechanical characteristic information also includes tensile strength.

[0062] Alternatively, the fracture step length l of a hard rock formation can be calculated by the following formula: ：

[0063]

[0064] Among them, σ t Can be used to express tensile strength.

[0065] As an optional implementation method, in response to there being multiple initial sub-rock layers, the fracture step threshold is the fracture step of each initial sub-rock layer below the initial sub-rock layer, or the fracture step of the initial sub-rock layer above the initial sub-rock layer, wherein a target sub-rock layer is determined from at least one initial sub-rock layer, including: in response to the fracture step of the initial sub-rock layer being greater than the fracture step of each initial sub-rock layer below the initial sub-rock layer, the initial sub-rock layer is determined to be the target sub-rock layer; in response to the fracture step of the initial sub-rock layer being less than the fracture step of the initial sub-rock layer above the initial sub-rock layer, the initial sub-rock layer and the initial sub-rock layer above the initial sub-rock layer are determined to be the target sub-rock layer.

[0066] In this embodiment, when there are multiple initial sub-rock layers and the fracture step threshold is the fracture step of each initial sub-rock layer below the initial sub-rock layer, or the fracture step of the initial sub-rock layer above the initial sub-rock layer, in the process of determining the target sub-rock layer from at least one initial sub-rock layer, when the fracture step of the initial sub-rock layer is greater than the fracture step of each initial sub-rock layer below the initial sub-rock layer, the initial sub-rock layer can be determined as the target sub-rock layer; when the fracture step of the initial sub-rock layer is less than the fracture step of the initial sub-rock layer above the initial sub-rock layer, the initial sub-rock layer and the initial sub-rock layer above the initial sub-rock layer are determined as the target sub-rock layer.

[0067] Optionally, if the fracture step length of the initial sub-layer is greater than the fracture step length of each initial sub-layer below the initial sub-layer, that is, l i >l j , we can determine that the jth layer is the key layer (j is the hard rock layer below the i layer). If the fracture step of the initial sub-layer is smaller than the fracture step of the initial sub-layer above the initial sub-layer, that is, l i <l i-1 , then the hard rock layer i-1 adds j layers to bear the load and recalculates the fracture step l i-1 If l i >l i-1 , then the i-th layer and the i-1-th layer are composite key layers.

[0068] As an optional implementation method, the detection results include a first detection result, a second detection result and a third detection result, the first detection result is used to determine the bending subsidence zone, the second detection result is used to determine the fracture zone, and the third detection result is used to determine the collapse zone, wherein the target sub-rock layer is detected to obtain the detection results, including: obtaining the lower delamination space corresponding to the target sub-rock layer, and determining the first detection result based on the lower delamination space and the maximum bending subsidence vertical deformation; determining the second detection result based on the lower delamination space and the extreme instability settlement corresponding to the target sub-rock layer; determining the settlement distance corresponding to the target sub-rock layer based on the lower delamination space; determining the rotation angle data of the key block after the target sub-rock layer is fractured based on the settlement distance; determining the third detection result based on the rotation angle data, the maximum rotation angle data and the blockiness data of the key block.

[0069] In this embodiment, in the process of detecting the target sub-rock layer and obtaining the detection results, the lower delamination space corresponding to the target sub-rock layer can be obtained, and the first detection result can be determined based on the lower delamination space and the maximum bending sinking vertical deformation; the second detection result can be determined based on the lower delamination space and the ultimate instability settlement amount corresponding to the target sub-rock layer; the settlement distance corresponding to the target sub-rock layer can be determined based on the lower delamination space; the rotation angle data of the key block after the target sub-rock layer is fractured can be determined based on the settlement distance; the third detection result can be determined based on the rotation angle data, the maximum rotation angle data and the blockiness data of the key block.

[0070] Optionally, the lower separation space is an important geological parameter in coal mining engineering, which mainly refers to the void or crack space below the key layer caused by the movement, fracture or bending of the overburden after coal mining. The maximum bending and sinking vertical deformation can be used to evaluate the deformation capacity of the rock layer under mining disturbance, especially the bending and sinking characteristics of the rock layer. The settlement distance is the vertical decline of the ground or underground rock layer relative to its original position under the action of gravity, mining disturbance or other external forces, which can reflect the impact of mining activities on the structural stability of the overburden and the ground environment. The rotation angle data is used to indicate the degree of rotation and displacement of the rock layer or rock block under mining disturbance, which is related to the structural change of the rock layer and the movement state of the overburden. The block size data of the key block mainly refers to the ratio of the thickness to the length of the key block, that is, the thickness-to-length ratio of the key block, which can affect the mechanical behavior in the overburden, and thus is related to the formation and evolution of the collapse zone, fault zone and bending sinking zone.

[0071] Optionally, based on the rotation angle data sinθ i+k 、Maximum rotation angle data sinθ i+k / max And the block size data α of the key block, determine the third detection result, which can be determined by the following formula:

[0072] α≤0.5+2sinθ i+k / max -sinθ i+k

[0073] As an optional implementation method, obtaining the lower delamination space corresponding to the target sub-rock layer includes: determining the lower delamination space based on the recovery rate of the coal seam corresponding to the target sub-rock layer, the thickness of the coal seam, and the total thickness of the sub-rock layer below the target sub-rock layer; before determining the first detection result based on the lower delamination space and the maximum bending and sinking vertical deformation, the method also includes: determining the maximum bending and sinking vertical deformation based on the cumulative load, elastic modulus and thickness of the target sub-rock layer; determining the first detection result based on the lower delamination space and the maximum bending and sinking vertical deformation, including: in response to the lower delamination space being greater than or equal to the maximum bending and sinking vertical deformation, determining that the detection result is that the target sub-rock layer is in a fractured state; based on the first detection result, determining three vertical zones from the target sub-rock layer, including: in response to the lower delamination space being less than the maximum bending and sinking vertical deformation, determining the first detection result is that the target sub-rock layer is not in a fractured state, and determining the target sub-rock layer and the sub-rock layer above the target sub-rock layer as a bending and sinking zone.

[0074] In this embodiment, in the process of obtaining the lower separation space corresponding to the target sub-rock layer, the lower separation space can be determined based on the recovery rate of the coal seam corresponding to the target sub-rock layer, the thickness of the coal seam, and the total thickness of the sub-rock layer below the target sub-rock layer. Before determining the first detection result based on the lower separation space and the maximum bending and sinking vertical deformation, the maximum bending and sinking vertical deformation can be determined based on the cumulative load, elastic modulus and thickness of the target sub-rock layer; the first detection result can be determined based on the lower separation space and the maximum bending and sinking vertical deformation. If the lower separation space is greater than or equal to the maximum bending and sinking vertical deformation, it can be determined that the detection result is that the target sub-rock layer is in a fractured state. In the process of determining the vertical three zones from the target sub-rock layer based on the first detection result, when the lower separation space is less than the maximum bending and sinking vertical deformation, the first detection result can be determined that the target sub-rock layer is not in a fractured state, and the target sub-rock layer and the sub-rock layer above the target sub-rock layer are determined as the bending and sinking zone. The sub-rock layer above the target sub-rock layer, that is, the key layer i and the overlying rock layer.

[0075] Optionally, the lower separation space ω can be determined by the following formula: i :

[0076] ω i =K p ′[(1-c)M i +∑h i ]

[0077] Among them, K p ′ can be used to represent the expansion coefficient of the broken rock mass in the collapse zone; c can be used to represent the recovery rate of the upper coal seam; M i Can be used to indicate the thickness of coal seams in m; ∑h iIt can be used to indicate the total thickness of the rock layer below the key layer i, in meters.

[0078] Optionally, the maximum bending and sinking vertical deformation ω can be determined by the following formula: max :

[0079]

[0080] Among them, lci can be used to represent the initial breaking step of key layer j, in m.

[0081] Optionally, when the lower separation space is greater than or equal to the maximum bending sinking vertical deformation, that is, ω i ≥ω max , then the key layer i breaks. When the space of the lower separation layer is less than the maximum bending and sinking vertical deformation, that is, ω i <ω max , then the key layer i and the overlying rock strata are curved subsidence zones.

[0082] As an optional implementation method, the extreme instability settlement amount includes a first extreme instability settlement amount and a second extreme instability settlement amount, the first extreme instability settlement amount is less than the second extreme instability settlement amount, wherein, based on the lower delamination space and the extreme instability settlement amount corresponding to the target sub-rock layer, a second detection result is determined, including: in response to the lower delamination space being greater than or equal to the first extreme instability settlement amount, and the lower delamination space being less than or equal to the second extreme instability settlement amount, determining that the second detection result is that the target sub-rock layer is in a fractured state; based on the second detection result, determining three vertical zones from the target sub-rock layer, including: in response to the lower delamination space being greater than or equal to the first extreme instability settlement amount, and the lower delamination space being less than or equal to the second extreme instability settlement amount, determining the target sub-rock layer and the sub-rock layer above the target sub-rock layer as fracture zones.

[0083] In this embodiment, in the process of determining the second detection result based on the lower delamination space and the limit instability settlement corresponding to the target sub-rock layer, the second detection result can be determined as the target sub-rock layer is in a fractured state when the lower delamination space is greater than or equal to the first limit instability settlement and the lower delamination space is less than or equal to the second limit instability settlement. In the process of determining the vertical three zones from the target sub-rock layer based on the second detection result, the target sub-rock layer and the sub-rock layer above the target sub-rock layer can be determined as a fracture zone when the lower delamination space is greater than or equal to the first limit instability settlement and the lower delamination space is less than or equal to the second limit instability settlement. The key layer i and its load rock layer are fracture zones.

[0084] Alternatively, the key block sliding instability condition can be determined by the following formula:

[0085]

[0086] Among them, σ c It can be used to indicate the compressive strength of rock formations, in MPa; ρ i Can be used to represent the density of the i-th rock layer in kg / m 3 ; g can be used to represent the acceleration due to gravity; Can be used to represent the friction coefficient between blocks; θ i Can be used to represent the key block rotation angle.

[0087] Alternatively, the key block rotation instability condition can be determined by the following formula:

[0088]

[0089] Among them, α can be used to represent the key block thickness-to-length ratio, which can be determined by the following formula:

[0090]

[0091] The vertical displacement caused by the rotation of the key block after the key layer i is fractured is the settlement distance ω′ of the rock layer i , then the rotation angle can be determined by the following formula:

[0092]

[0093] Among them, L zd It can be used to represent the key block rotation span, in meters, which can be determined by the following formula:

[0094]

[0095] Optionally, the first limit instability settlement can be determined by the following formula:

[0096]

[0097] Optionally, the second limit instability settlement can be determined by the following formula:

[0098]

[0099] Optionally, the lower separation space is greater than or equal to the first limit instability settlement, and the lower separation space is less than or equal to the second limit instability settlement, which can be determined by the following formula:

[0100] ω′ i / min ≥ω i ≥ω′ i / max

[0101] When the above formula is satisfied, it can be determined that the second detection result is that the target sub-rock layer is in a fractured state.

[0102] As an optional implementation method, a third detection result is determined based on the rotation angle data, the maximum rotation angle data and the block size data of the key block, including: determining a block size threshold of the block size based on the rotation angle data and the maximum rotation angle data; determining the third detection result in response to the block size being less than or equal to the block size threshold; determining three vertical zones from the target sub-rock layer based on the third detection result, including: determining the target sub-rock layer and the sub-rock layer above the target sub-rock layer as collapse zones in response to the block size being less than or equal to the block size threshold.

[0103] In this embodiment, in the process of determining the third detection result based on the rotation angle data, the maximum rotation angle data, and the block size data of the key block, the block size threshold of the block size can be determined based on the rotation angle data and the maximum rotation angle data; when the block size is less than or equal to the block size threshold, the third detection result can be determined. In the process of determining the vertical three zones from the target sub-rock layer based on the third detection result, when the block size is less than or equal to the block size threshold, the target sub-rock layer and the sub-rock layer above the target sub-rock layer can be determined as the collapse zone.

[0104] Optionally, the blockiness threshold of the blockiness can be determined by the following formula:

[0105] 0.5+2sinθ i / max -sinθ i

[0106] If the blockiness is less than or equal to the blockiness threshold, that is, when the following formula is satisfied, the key layer i and its load rock layer are fault zones, otherwise the key layer i and the load layer are collapse zones.

[0107] α≤0.5+2sinθ i / max -sinθ i

[0108] Optionally, when the key block reaches the maximum rotation angle θ i | max When , the maximum rotation angle data can be determined by the following formula:

[0109]

[0110] In an embodiment of the present invention, if the three vertical zones in the overburden are to be determined, the mechanical characteristic information and geological characteristic information corresponding to the overburden above the coal seam can be obtained; based on the mechanical characteristic information and the geological characteristic information, the cumulative loads corresponding to the multiple sub-rock layers in the overburden are determined respectively, and based on the cumulative loads, at least one initial sub-rock layer is screened out from the multiple sub-rock layers; at least based on the cumulative load, the fracture step of at least one initial sub-rock layer is determined, and based on the fracture step, the target sub-rock layer is determined from the at least one initial sub-rock layer; the target sub-rock layer is detected to obtain the detection result, and based on the detection result, the three vertical zones are determined from the target sub-rock layer. In this embodiment, the target sub-rock layer (key layer) is determined by screening the sub-rock layers twice. The first time, the cumulative load is determined to screen out the initial sub-rock layer, which is more comprehensive than the empirical method. The second time, the fracture step of different initial sub-rock layers and the corresponding fracture step threshold are compared to screen out the key layer that is prone to produce the three vertical zones. By evaluating whether the key layer is in a fractured state, it is possible to determine whether three vertical zones are generated in the key layer, and accurately determine whether it is a fracture zone, a collapse zone or a curved subsidence zone, making the determination of the three vertical zones more comprehensive and objective, thereby achieving the technical effect of improving the accuracy of determining the three vertical zones in the overburden rock, and solving the technical problem of low accuracy in determining the three vertical zones in the overburden rock.

[0111] The technical solution of the embodiment of the present invention is illustrated below in conjunction with preferred implementation modes.

[0112] At present, after coal seam mining, the equilibrium state of the overburden strata in the mining area is disturbed by the mining of the working face, causing the bending, fracture, and collapse of the overburden strata, and finally forming a collapse zone, a fracture zone, and a curved sinking zone in the vertical direction of the mining area, collectively known as the "three vertical zones", or the three vertical zones. Among them, the collapse zone and the fracture zone are collectively known as the water-conducting fracture zone. The pre-determination of the water-conducting fracture zone is of great significance for mining under water and determining the role of the liberation layer when mining coal seams with outburst dangers.

[0113] In the related art, single coal seam mining often adopts empirical formulas, and the three vertical zones are determined by the mining thickness. However, for most shallow coal seams, there is no curved subsidence zone, so empirical formulas are no longer commonly used. The embodiment of the present invention proposes a method for determining the three vertical zones of overlapping disturbed overburden in a shallow coal seam group, introduces the key layer theory, and solves the problem of inaccurate division of the three vertical zones in shallow coal seam mining. In particular, when there is overlapping mining, the three vertical zones of the overburden will be disturbed twice to form new three vertical zones. In summary, the key layer is used as a more objective judgment basis to divide the three vertical zones of overlapping disturbed overburden in a shallow coal seam group, which is beneficial to the safe production of coal mines, thereby achieving the technical effect of improving the accuracy of determining the three vertical zones in the overburden, and solving the technical problem of low accuracy in determining the three vertical zones in the overburden.

[0114] The embodiments of the present invention are further described below.

[0115] In an embodiment of the present invention, Figure 2 1 is a flow chart of a method for determining three vertical zones of overlapping disturbed overburden in a shallow buried coal seam group according to an embodiment of the present invention. Figure 2 As shown, the following steps may be included:

[0116] Step S201, obtaining the structure, lithology and mechanical parameters of the overlying rock layer.

[0117] In this embodiment, the structure, lithology and mechanical parameters of the overburden and coal seams can be collected, including the thickness, occurrence, compressive strength, tensile strength, compressive strength, bulk density, thickness, elastic modulus and Poisson's ratio of the overburden and coal seams.

[0118] Step S202, hard rock layer identification: q n q n+1 .

[0119] In this embodiment, the cumulative load of each rock layer can be calculated from top to bottom, and the cumulative load q of the nth layer is taken as n The cumulative load q of the n+1 layer n+1 Compare. When q n q n+1 When , execute step S203; otherwise, execute step S204.

[0120] Alternatively, the cumulative load on the formation can be determined by the following formula:

[0121]

[0122] Among them, q n It can be used to represent the cumulative load of the rock formation, with the unit of N; E can be used to represent the elastic modulus, for example, E i It can be used to represent the elastic modulus of the i-th rock layer in GPa; h can be used to represent the thickness of the rock layer, for example, h i It can be used to indicate the thickness of the i-th rock layer in meters.

[0123]

[0124] Among them, W n Can be used to indicate the weight of rock formation, the unit is KN; V n Can be used to express the volume of rock formations in m 3 .

[0125] Step S203, calculating the fracture step distance of the hard rock layer i.

[0126] In this embodiment, when q n q n+1The fracture step distance of hard rock layer i can be calculated.

[0127] Alternatively, the fracture step length l of a hard rock formation can be calculated by the following formula: ：

[0128]

[0129] Among them, σ t Can be used to express tensile strength.

[0130] Step S204: the rock layer is a load layer.

[0131] In this embodiment, when q n >q n+1 If it is not satisfied, it cannot be determined that the nth layer is a hard rock layer and the rock layer is a load-bearing layer.

[0132] Step S205, 1 i ≤l i-1 .

[0133] In this embodiment, the fracture step distance between the hard rock layer i and the layer i-1 can be determined. i ≤l i-1 , execute step S206.

[0134] Step S206, the hard rock layer i-1 increases the load bearing by i layers and recalculates the fracture step li-1.

[0135] In this embodiment, the fracture step li-1 can be recalculated by increasing the load bearing layer i-1 by the hard rock layer i-1.

[0136] Step S207, 1 i >l j .

[0137] In this embodiment, the fracture step distance between the hard rock layer i and the layer i-1 can be determined. i >l j , execute step S208.

[0138] Step S208: the i-th layer and the i-1-th layer are composite key layers.

[0139] In this embodiment, when the fracture step distance between the hard rock layer i and the i-1 layer, l i >l j When , the i-th layer and the i-1-th layer are composite key layers.

[0140] Step S209, 1 i >l j (j is all the hard layers below layer i).

[0141] In this embodiment, when the hard rock layer i is larger than all the hard layers below layer i, step S210 is executed.

[0142] Step S210, the i-th layer is a key layer.

[0143] In this embodiment, when the hard rock layer i is larger than all the hard layers below the i-th layer, the i-th layer is a key layer.

[0144] Through the above steps S201 to S210, key layer identification can be performed.

[0145] Step S211, w i ≥w max .

[0146] In this embodiment, when the lower separation space w i Greater than its maximum bending and sinking vertical deformation w max If the critical layer i is broken, the step S212 is executed; otherwise, the step S216 is executed.

[0147] Optionally, to determine whether the key layer i is broken, the stress structure of the shallow coal seam before the initial fracture can be regarded as a "simply supported beam" structure. The basis for the breaking of the key layer i of the "simply supported beam" structure is the lower separation space w i Is it greater than its maximum bending and sinking vertical deformation w? max , that is, w i ≥w max .

[0148] The lower separation space can be determined by the following formula:

[0149] ω i =K p ′[(1-c)M i +∑h i ]

[0150] Among them, K p ′ can be used to indicate the expansion coefficient of the broken rock mass in the collapse zone; c can be used to indicate the recovery rate of the upper coal seam; M can be used to indicate the thickness of the coal seam, in m; ∑h i It can be used to indicate the total thickness of the rock layer below the key layer i, in meters.

[0151] The maximum bending and sinking vertical deformation can be determined by the following formula:

[0152]

[0153] Among them, lc i It can be used to indicate the initial breaking step of key layer i, in m.

[0154] Step S212, ω′ i / min ≥ω i ≥ω′ i / max .

[0155] In this embodiment, it can be determined whether the separation space of the key layer i is within the limit instability settlement of the "masonry beam" structure, that is, ω′ i / min ≥ω i ≥ω′ i / max . When the space below the layer ω i When it is greater than or equal to its maximum bending and sinking vertical deformation and less than or equal to the minimum bending and sinking vertical deformation, a stable "masonry beam" structure can be formed after the key layer i is broken, and the key layer i and its load rock layer are fracture zones, and step S215 is executed; otherwise, step S213 is executed.

[0156] Optionally, the vertical displacement caused by the rotation of the key block after the key layer i is fractured is the settlement distance ω′ of the rock layer i , then the rotation angle can be determined by the following formula:

[0157] sinθ i =w i / L zd

[0158] Among them, L zd It can be used to indicate the rotation span of key blocks in m.

[0159]

[0160] Alternatively, the ultimate instability settlement of the "masonry beam" structure can be determined by the following formula:

[0161]

[0162] Among them, g can be used to represent the acceleration due to gravity.

[0163] Among them, α can be used to represent the key block thickness-to-length ratio, which can be determined by the following formula:

[0164]

[0165] Thus, the separation space ω of the key layer i can be determined i Is it within the limit instability settlement of the "masonry beam" structure, that is: ω′ i / min ≥ω i ≥ω′ i / maX .

[0166] Step S213, α≤0.5+2sinθ i / max -sinθ i .

[0167] In this embodiment, when the key block size α≤0.5+2sinθ i / max -sinθ i , then execute step S215, otherwise, execute step S214.

[0168] Optionally, if the separation space ω below the key layer i i If the value is too large, it is impossible to form a "masonry beam" after the fracture. Then, after the critical layer i is fractured, can the key block form a "step rock beam" structure? i | max It can be determined by the following formula:

[0169] sinθ i | max =w′ i / L zd

[0170] When the key block reaches the maximum rotation angle, the condition for the “step rock beam” structure not to slide and become unstable is that the key block size α satisfies the following formula:

[0171] α≤0.5+2sinθ i / max -sinθ i

[0172] Then the key layer i and its load rock layer are fault zones, otherwise the key layer i and the load layer are collapse zones.

[0173] Step S214, the key layer i and the load layer are collapse zones.

[0174] In this embodiment, α≤0.5+2sinθ i / max -sinθ i If it is not satisfied, the key layer i and the load layer are collapse zones.

[0175] Step S215, the key layer i and its load rock layer are fault zones.

[0176] In this embodiment, α≤0.5+2sinθ i / max -sinθ i When it is satisfied, the key layer i and the load layer are collapse zones.

[0177] Step S216: the key layer i and the overlying layer are curved subsidence zones.

[0178] In this embodiment, when the lower separation space w i Does not meet the maximum bending and sinking vertical deformation w max When , the key layer i and the overlying layer are curved subsidence zones.

[0179] Through the above steps S211 to S216, the vertical three-zone identification of overlying strata in upper coal seam mining can be achieved.

[0180] Step S217, ω i+k ≥ω max +ω i .

[0181] In this embodiment, when the lower coal seam is mined, the three vertical zones of overlapping disturbance overburden of the coal seam are determined by the delamination space determined by the upper coal seam, the delamination space of the key layer, the maximum bending amount, and the formation of masonry beam structure and step beam structure.

[0182] Optionally, to determine whether the key layer i+k is broken, the separation space ω below the key layer can be calculated. i+k Is it greater than the maximum bending and sinking vertical deformation ω max and the critical layer i separation space ω i The sum of, that is:

[0183] ω i+k ≥ω max +ω i

[0184] Step S218, ω′ i+k / min ≥ω i+k ≥ω′ i+k / max .

[0185] In this embodiment, ω′ i+k / min ≥ω i+k ≥ω′ i+k / max If ω′ i+k / min ≥ω i+k ≥ω′ i+k / max If it is established, the key layer i+k is broken.

[0186] Alternatively, the separation space below the key layer can be determined by the following formula:

[0187] ω i+k =K p [(1-c)M i+k +∑h i+k ]

[0188]

[0189] Optionally, by judging whether a stable "masonry beam" structure can be formed after its fracture, the conditions under which the key blocks of the "masonry beam" do not become unstable, and the sliding instability condition can be determined by the following formula:

[0190]

[0191] The rotation instability condition can be determined by the following formula:

[0192]

[0193] The vertical displacement caused by the rotation of the key block after the key layer i+k is the settlement distance ω′ of the rock layer. i+k , the rotation angle can be determined by the following formula:

[0194]

[0195] Substituting the above formula into the sliding instability condition and the rotation instability condition formula, the ultimate instability settlement of the "masonry beam" structure can be obtained as follows:

[0196]

[0197] At this point, we can determine the critical layer i+k separation space ω i+k Whether it is within the limit instability settlement of the "masonry beam" structure, that is:

[0198] ω′ i+k / min ≥ω i+k ≥ω′ i+k / max

[0199] If ω′ i+k / min ≥ω i+k ≥ω′ i+k / max If it is established, a stable "masonry beam" structure can be formed after the key layer i+k is fractured, and the key layer i+k and its load rock layer are the fracture zone. If it is not established, execute step S219.

[0200] Step S219, α≤0.5+2sinθ i+k / max -sinθ i+k .

[0201] In this embodiment, if the separation space ω below the key layer i+k is i+kIf the critical layer i is too large, it cannot form a "masonry beam" after the fracture. Then, can the critical block form a "step rock beam" structure after the critical layer i is fractured? When the critical block reaches the maximum rotation angle, that is:

[0202]

[0203] The condition for the “step rock beam” structure to not slide and become unstable is that the critical block size α satisfies the following formula:

[0204] α≤0.5+2sinθ i+k / max -sinθ i+k

[0205] If the key block size α satisfies α≤0.5+2sinθ i+k / max -sinθ i+k , the key layer i+k and its load rock layer are fault zones, whereas the key layer i+k and the load layer are collapse zones.

[0206] Step S220, the key layer i+k and the load layer are collapse zones.

[0207] In this embodiment, if α≤0.5+2sinθ i+k / max -sinθ i+k If it is not true, the key layer i+k and the load layer are collapse zones.

[0208] Step S221, the key layer i+k and its load rock layer are fault zones.

[0209] In this embodiment, if α≤0.5+2sinθ i+k / max -sinθ i+k If it is established, the key layer i+k and its load rock layer are fault zones.

[0210] Step S222: the key layer i+k and the overlying layer are curved sinking zones.

[0211] In this embodiment, if ω i+k ≥ω max +ω i If it is not true, the key layer i+k and the overlying layer are curved subsidence zones.

[0212] Through the above steps S217 to S222, the vertical three-zone discrimination of the overlapping and disturbed overburden of the coal seam can be achieved.

[0213] In the embodiment of the present invention, a more objective judgment basis is used to divide the three vertical zones under overlapping mining of shallow buried coal seam groups, thereby improving the accuracy of division and the prediction accuracy of water-conducting fracture zones. The three vertical zones can be more accurately determined when mining under water bodies and mining coal seams with outstanding dangers. This has theoretical guiding significance for the safe and efficient mining of overlapping mining areas of shallow buried coal seam groups in my country, thereby achieving the technical effect of improving the accuracy of determining the three vertical zones in the overburden, and solving the technical problem of low accuracy in determining the three vertical zones in the overburden.

[0214] The following uses a working face in a mine where a group of shallow coal seams are mined in overlap as the engineering background, divides the positions of the three vertical zones where a group of shallow coal seams are mined in overlap, and further explains.

[0215] Select a shallow coal seam group overlapping disturbance working face, and obtain the structure, lithology and mechanical parameters of the overlying rock layer through drilling, including the thickness, occurrence, compressive strength, tensile strength, compressive strength, bulk density, thickness, elastic modulus and Poisson's ratio of the coal and rock layers. Calculate the cumulative load of each rock layer from top to bottom, and take the cumulative load q of the nth layer n The cumulative load q of the n+1 layer n+1 Compare all the hard rock layers i, and there is l hard rock layer after comparison, which is located 16m above the coal seam and has a rock layer thickness of 10.5m of medium-grained sandstone. Calculate the fracture step l of the hard rock layer from top to bottom to determine whether the hard rock layer is a key layer. The fracture step l of the hard rock layer 坚硬 =30.5m, which is greater than the fracture step of all the rock layers below, so the i-th layer is the key layer. According to the separation space, maximum bending amount and the formation of masonry beam structure and step beam structure of the key layer, the vertical three zones of shallow buried overlapping disturbance overburden are determined. The thickness of the upper coal seam is 6.2m, the separation space below the key layer 1 is ω1=3m, and the maximum bending sinking vertical deformation is ω max =1.3,ω1>ω max , key layer 1 is broken. After the key layer 1 is broken, the separation space is large and no layer is formed, forming a "step rock beam" structure α=0.51, satisfying α≤0.5+2sinθ i / max -sinθ i , with key layer 1 as the boundary, the lower part is the collapse zone, and key layer 1 and its load rock layer are fault zones. If there is only one key layer, the structure of key layer 1 can determine the overall state of the overburden of the upper coal seam, that is, with key layer 1 as the boundary, the lower part is the collapse zone, and key layer 1 and its load rock layer are fault zones, and there is no curved sinking zone.

[0216] Figure 3 is a schematic diagram of a vertical three-zone division of coal seam mining according to an embodiment of the present invention, such as Figure 3 As shown, the short black frame in the figure can represent the 1# coal seam, and the long black frame can represent the 2# coal seam.

[0217] According to an embodiment of the present invention, a device for determining three vertical zones in overburden is also provided. It should be noted that the device for determining three vertical zones in overburden can be used to execute the method for determining three vertical zones in overburden in the above embodiment.

[0218] Figure 4 Schematic diagram of a device for determining three vertical zones in overburden according to an embodiment of the present invention. Figure 4 As shown, the device 400 for determining three vertical zones in the overburden may include: an acquisition unit 402 , a first determination unit 404 , a second determination unit 406 and a third determination unit 408 .

[0219] The acquisition unit 402 is used to acquire mechanical characteristic information and geological characteristic information corresponding to the overburden above the coal seam, wherein the mechanical characteristic information is used to indicate the stability of the overburden under different forces, and the geological characteristic information is used to indicate the stability of the structure of the overburden.

[0220] The first determination unit 404 is used to determine the cumulative loads corresponding to multiple sub-rock layers in the overburden based on the mechanical characteristic information and the geological characteristic information, and select at least one initial sub-rock layer from the multiple sub-rock layers based on the cumulative loads, wherein the initial sub-rock layer is a sub-rock layer whose cumulative load meets the cumulative load threshold among the multiple sub-rock layers.

[0221] The second determination unit 406 is used to determine the fracture step length of at least one initial sub-rock layer based on at least the cumulative load, and determine the target sub-rock layer from the at least one initial sub-rock layer based on the fracture step length, wherein the fracture step length of the target sub-rock layer meets the fracture step length threshold.

[0222] The third determination unit 408 is used to detect the target sub-rock layer, obtain the detection result, and determine the three vertical zones from the target sub-rock layer based on the detection result, wherein the detection result is used to indicate whether the target sub-rock layer is in a fractured state, and the three vertical zones include a collapse zone, a fracture zone and a curved subsidence zone.

[0223] In the embodiment of the present invention, mechanical characteristic information and geological characteristic information corresponding to the overburden above the coal seam are obtained by an acquisition unit 402, wherein the mechanical characteristic information is used to indicate the stability of the overburden under the action of different forces, and the geological characteristic information is used to indicate the stability of the structure of the overburden; the first determination unit 404 determines the cumulative loads corresponding to multiple sub-rock layers in the overburden based on the mechanical characteristic information and the geological characteristic information, and based on the cumulative load, selects at least one initial sub-rock layer from the multiple sub-rock layers, wherein the initial sub-rock layer is a sub-rock layer whose cumulative load meets the cumulative load threshold among the multiple sub-rock layers; the second determination unit 406 determines the cumulative loads corresponding to the multiple sub-rock layers based on the cumulative loads. load, determine the fracture step length of at least one initial sub-rock layer, and based on the fracture step length, determine the target sub-rock layer from the at least one initial sub-rock layer, wherein the fracture step length of the target sub-rock layer meets the fracture step length threshold; detect the target sub-rock layer through the third determination unit 408 to obtain the detection result, and determine the three vertical zones from the target sub-rock layer based on the detection result, wherein the detection result is used to indicate whether the target sub-rock layer is in a fracture state, and the three vertical zones include a collapse zone, a fracture zone and a curved subsidence zone, thereby achieving the technical effect of improving the accuracy of determining the three vertical zones in the overburden, and solving the technical problem of low accuracy in determining the three vertical zones in the overburden.

[0224] According to an embodiment of the present invention, a computer-readable storage medium is further provided. The storage medium includes a stored program, and the program executes the method for determining three vertical zones in overburden in the above embodiment.

[0225] According to an embodiment of the present invention, a processor is further provided, the processor being used to run a program, wherein when the program is run, the method for determining three vertical zones in overburden in the above embodiment is executed.

[0226] The embodiment of the present application further provides a computer program product. Optionally, in the present embodiment, the computer program product may include a computer program, and when the computer program is executed by a processor, the method for determining three vertical zones in overburden in the embodiment of the present application is implemented.

[0227] In the above embodiments of the present invention, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0228] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only schematic. For example, the division of the units can be a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of units or modules, which can be electrical or other forms.

[0229] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0230] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0231] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, Read-Only Memory (ROM), Random Access Memory (RAM), mobile hard disk, magnetic disk or optical disk, etc., various media that can store program codes.

[0232] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for determining three vertical zones in overburden, characterized in that: include: Acquire mechanical characteristic information and geological characteristic information corresponding to the overburden above the coal seam, wherein the mechanical characteristic information is used to indicate the stability of the overburden under the action of different forces, and the geological characteristic information is used to indicate the stability of the structure of the overburden; Based on the mechanical characteristic information and the geological characteristic information, respectively determine the cumulative loads corresponding to the multiple sub-rock layers in the overburden, and based on the cumulative loads, select at least one initial sub-rock layer from the multiple sub-rock layers, wherein the initial sub-rock layer is a sub-rock layer among the multiple sub-rock layers whose cumulative load meets a cumulative load threshold; Determining a fracture step distance of at least one of the initial sub-rock layers based at least on the cumulative load, and determining a target sub-rock layer from the at least one of the initial sub-rock layers based on the fracture step distance, wherein the fracture step distance of the target sub-rock layer satisfies a fracture step distance threshold; The target sub-rock layer is tested to obtain a test result, and based on the test result, three vertical zones are determined from the target sub-rock layer, wherein the test result is used to indicate whether the target sub-rock layer is in a fractured state, and the three vertical zones include a collapse zone, a fracture zone and a curved subsidence zone.

2. The method according to claim 1, characterized in that The mechanical characteristic information includes at least the elastic modulus of the overburden, and the geological characteristic information includes at least the thickness, weight and volume of the overburden, wherein the cumulative loads corresponding to multiple sub-rock layers in the overburden are determined based on the mechanical characteristic information and the geological characteristic information, respectively, including: According to the arrangement order of the plurality of sub-rock layers in the overburden, the cumulative load of the sub-rock layers is determined based on the elastic modulus, the thickness, the weight and the volume respectively corresponding to different sub-rock layers.

3. The method according to claim 2, characterized in that The cumulative load threshold is the cumulative load of the next sub-rock layer of the sub-rock layer, wherein at least one initial sub-rock layer is selected from the plurality of sub-rock layers based on the cumulative load, including: In response to the cumulative load of the sub-stratum being greater than the cumulative load of a next sub-stratum of the sub-stratum, determining the sub-stratum to be the initial sub-stratum; The method further includes: in response to the cumulative load of the sub-stratum being less than or equal to the cumulative load threshold, determining that the sub-stratum is not the initial sub-stratum.

4. The method according to claim 2, characterized in that: The mechanical characteristic information also includes tensile strength, wherein the fracture step distance of at least one of the initial sub-rock layers is determined based at least on the cumulative load, including: The fracture step distance is determined based on the thickness of the initial sub-stratum, the tensile strength and the cumulative load.

5. The method according to claim 4, characterized in that In response to the number of the initial sub-rock layers being multiple, the fracture step threshold is the fracture step of each of the initial sub-rock layers below the initial sub-rock layer, or the fracture step of the initial sub-rock layer above the initial sub-rock layer, wherein determining a target sub-rock layer from at least one of the initial sub-rock layers comprises: In response to the fracture step length of the initial sub-rock layer being greater than the fracture step lengths of each of the initial sub-rock layers below the initial sub-rock layer, determining the initial sub-rock layer as the target sub-rock layer; In response to the fracture step distance of the initial sub-layer being smaller than the fracture step distance of the initial sub-layer above the initial sub-layer, the initial sub-layer and the initial sub-layer above the initial sub-layer are determined to be the target sub-layer.

6. The method according to claim 2, characterized in that The detection result includes a first detection result, a second detection result and a third detection result, wherein the first detection result is used to determine the curved subsidence zone, the second detection result is used to determine the fault zone, and the third detection result is used to determine the collapse zone, wherein the target sub-rock layer is detected to obtain the detection result, including: Acquire the lower delamination space corresponding to the target sub-rock layer, and determine the first detection result based on the lower delamination space and the maximum bending sinking vertical deformation; Determining the second detection result based on the lower delamination space and the limit instability settlement amount corresponding to the target sub-rock layer; Based on the lower detached space, determine the settlement distance corresponding to the target sub-rock layer; based on the settlement distance, determine the rotation angle data of the key block after the target sub-rock layer is fractured; based on the rotation angle data, the maximum rotation angle data and the block size data of the key block, determine the third detection result.

7. The method according to claim 6, characterized in that Obtaining the lower separation space corresponding to the target sub-stratum, including: Determine the lower separation space based on the recovery rate of the coal seam corresponding to the target sub-rock layer, the thickness of the coal seam, and the total thickness of the sub-rock layer below the target sub-rock layer; Before determining the first detection result based on the lower separation space and the maximum bending subsidence vertical deformation amount, the method further includes: determining the maximum bending subsidence vertical deformation amount based on the cumulative load, the elastic modulus and the thickness of the target sub-rock layer; Determining the first detection result based on the lower separation space and the maximum bending and sinking vertical deformation amount includes: in response to the lower separation space being greater than or equal to the maximum bending and sinking vertical deformation amount, determining that the detection result is that the target sub-rock layer is in the fracture state; Based on the first detection result, three vertical zones are determined from the target sub-rock layer, including: in response to the lower delamination space being smaller than the maximum bending and sinking vertical deformation, determining that the first detection result is that the target sub-rock layer is not in the fracture state, and determining the target sub-rock layer and the sub-rock layer above the target sub-rock layer as the bending and sinking zone.

8. The method according to claim 6, characterized in that The limit instability settlement amount includes a first limit instability settlement amount and a second limit instability settlement amount, the first limit instability settlement amount is less than the second limit instability settlement amount, wherein the second detection result is determined based on the lower delamination space and the limit instability settlement amount corresponding to the target sub-rock layer, including: In response to the lower separation space being greater than or equal to the first limit instability settlement amount, and the lower separation space being less than or equal to the second limit instability settlement amount, determining that the second detection result is that the target sub-rock layer is in the fracture state; Based on the second detection result, three vertical zones are determined from the target sub-rock layer, including: in response to the lower delamination space being greater than or equal to the first limit instability settlement amount, and the lower delamination space being less than or equal to the second limit instability settlement amount, the target sub-rock layer and the sub-rock layer above the target sub-rock layer are determined as the fault zone.

9. The method according to claim 6, characterized in that Determining the third detection result based on the rotation angle data, the maximum rotation angle data, and the block size data of the key block includes: Determining a blockiness threshold of the blockiness based on the rotation angle data and the maximum rotation angle data; In response to the blockiness being less than or equal to the blockiness threshold, determining the third detection result; Based on the third detection result, three vertical zones are determined from the target sub-rock layer, including: in response to the blockiness being less than or equal to the blockiness threshold, the target sub-rock layer and the sub-rock layer above the target sub-rock layer are determined as the collapse zone.

10. A device for determining three vertical zones in overburden, characterized in that: include: An acquisition unit, used to acquire mechanical characteristic information and geological characteristic information corresponding to the overburden above the coal seam, wherein the mechanical characteristic information is used to indicate the stability of the overburden under the action of different forces, and the geological characteristic information is used to indicate the stability of the structure of the overburden; a first determining unit, configured to determine, based on the mechanical characteristic information and the geological characteristic information, respectively the cumulative loads corresponding to the plurality of sub-rock layers in the overburden, and to select, based on the cumulative loads, at least one initial sub-rock layer from the plurality of sub-rock layers, wherein the initial sub-rock layer is a sub-rock layer in which the cumulative load satisfies a cumulative load threshold among the plurality of sub-rock layers; a second determining unit, configured to determine a fracture step distance of at least one of the initial sub-rock layers based at least on the accumulated load, and determine a target sub-rock layer from the at least one initial sub-rock layer based on the fracture step distance, wherein the fracture step distance of the target sub-rock layer satisfies a fracture step distance threshold; The third determination unit is used to detect the target sub-rock layer, obtain the detection result, and determine three vertical zones from the target sub-rock layer based on the detection result, wherein the detection result is used to indicate whether the target sub-rock layer is in a fractured state, and the three vertical zones include a collapse zone, a fracture zone and a curved subsidence zone.

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