Coal mine stope thick and hard roof underground long hole fracturing load reduction modification anti-impact analysis method

Abstract

The invention provides a coal mine stope thick and hard roof underground long hole fracturing load reduction modification rock burst prevention and control analysis method. The method comprises the steps that stope overlying thick and hard roof structure and dynamic load transfer engineering structure models on which underground long hole fracturing is not carried out and on which underground long hole fracturing is carried out are established respectively; on the basis of the model, obtaining advance static load stress of a working face where underground long hole fracturing is not carried out and underground long hole fracturing is carried out, and a first total dynamic load and a second total dynamic load which are transmitted to the working face and are formed when dynamic loads which are formed when the multi-layer thick and hard roof where underground long hole fracturing is not carried out and underground long hole fracturing is carried out are fractured periodically; and based on the advanced static load stress of the working face, the first total dynamic load and the second total dynamic load, analyzing to obtain an analysis result of the underground long hole fracturing prevention rock burst of the thick and hard roof of the coal mine stope. The thick and hard roof underground long hole fracturing load reduction modification rock burst prevention and control principle is clarified, and the thick and hard roof underground long hole fracturing rock burst prevention and control effect is improved.

Description

Technical Field

[0001] The present application relates to the field of coal mine safety technology, and in particular to an analysis method for preventing and controlling rock burst by underground long-hole fracturing and load reduction modification of thick hard roof in coal mines. Background Art

[0002] Deep coal mining often faces the problem of frequent rock bursts, which seriously threatens the safety of personnel and has an adverse impact on the efficient mining of coal resources. The main reason for rock bursts is the superposition of the high foundation static load of deep mining and the dynamic load of the overlying roof breaking in the mining area. Rock bursts occur when the sum of the static and dynamic loads reaches the critical value of coal rock mass impact instability.

[0003] Therefore, measures should be taken to reduce the high static load caused by deep mining or the strong dynamic load caused by the breaking of the thick hard roof in the mining area to prevent and control rock burst. In view of the strong dynamic load caused by the breaking of the thick hard roof, underground long hole fracturing and pressure relief projects have been carried out to reduce the dynamic load, and some results have been achieved. However, the principle of underground long hole fracturing and pressure relief for rock burst prevention and control is not well understood, which limits the effect of rock burst prevention and control.

[0004] Therefore, it is necessary to provide a method that can explain the principle of load reduction and modification of underground long-hole fracturing to prevent and control rock burst in thick hard roof overlying the mining area, which can provide technical guidance for underground long-hole fracturing to prevent and control rock burst in thick hard roof, so as to improve the effect of underground long-hole fracturing to prevent and control rock burst in thick hard roof. Summary of the invention

[0005] The present application aims to solve one of the technical problems in the related art at least to some extent.

[0006] To this end, the first purpose of this application is to propose an analysis method for underground long-hole fracturing to prevent and control rock burst in thick and hard roof of coal mines, and to explain the principle of load reduction and modification of underground long-hole fracturing to prevent and control rock burst in thick and hard roof, so as to improve the effect of underground long-hole fracturing to prevent and control rock burst in thick and hard roof.

[0007] The second purpose of the present application is to provide an underground long-hole fracturing and rock burst analysis device for thick and hard roof in coal mines.

[0008] The third objective of the present application is to provide an electronic device.

[0009] A fourth objective of the present application is to provide a computer-readable storage medium.

[0010] A fifth object of the present application is to provide a computer program product.

[0011] To achieve the above-mentioned purpose, the first embodiment of the present application proposes a method for analyzing underground long-hole fracturing to prevent and control rock burst in thick hard roof of a coal mine, comprising:

[0012] The thick hard roof structure and dynamic load transfer engineering structure model of the mining field without downhole long hole fracturing and the thick hard roof structure and dynamic load transfer engineering structure model of the mining field with downhole long hole fracturing were established respectively;

[0013] Based on the thick hard roof structure overlying the mining field where no downhole long hole fracturing is implemented and the dynamic load transfer engineering structure model, the leading static load stress of the working face where no downhole long hole fracturing is implemented and the first total dynamic load transmitted to the working face by the dynamic load formed when the multi-layer thick hard roof is periodically broken where no downhole long hole fracturing is implemented are calculated;

[0014] Based on the thick hard roof structure overlying the mining area where downhole long hole fracturing is implemented and the dynamic load transfer engineering structure model, the leading static load stress of the working face where downhole long hole fracturing is implemented and the second total dynamic load transmitted to the working face by the dynamic load formed when the multi-layer thick hard roof is periodically broken during downhole long hole fracturing are calculated;

[0015] Based on the advance static load stress of the working face where underground long hole fracturing is not implemented, the advance static load stress of the working face where underground long hole fracturing is implemented, the first total dynamic load and the second total dynamic load, the analysis results of underground long hole fracturing for preventing and controlling rock burst in thick hard roof of coal mine are obtained.

[0016] To achieve the above-mentioned purpose, the second embodiment of the present application proposes an underground long hole fracturing and rock burst analysis device for thick hard roof in a coal mine, comprising:

[0017] A model acquisition module is used to respectively establish a model of a thick hard roof structure and a dynamic load transfer engineering structure on a mining site where no downhole long hole fracturing is implemented and a model of a thick hard roof structure and a dynamic load transfer engineering structure on a mining site where downhole long hole fracturing is implemented;

[0018] A load calculation module, for calculating the first total dynamic load transmitted to the working face by the advanced static load stress of the working face where the downhole long hole fracturing is not implemented and the dynamic load formed when the multi-layer thick hard roof is periodically broken where the downhole long hole fracturing is not implemented, based on the thick hard roof structure overlying the mining field where the downhole long hole fracturing is not implemented and the dynamic load transfer engineering structure model;

[0019] The load calculation module is further used to calculate the leading static load stress of the working face for implementing downhole long hole fracturing and the second total dynamic load transmitted to the working face by the dynamic load formed when the multi-layer thick hard roof plate is periodically broken for implementing downhole long hole fracturing, based on the thick hard roof plate structure overlying the mining field for implementing downhole long hole fracturing and the dynamic load transfer engineering structure model;

[0020] The load analysis module is used to analyze and obtain the impact rock pressure analysis results of underground long hole fracturing for thick hard roof of coal mine based on the advanced static load stress of the working face where underground long hole fracturing is not implemented, the advanced static load stress of the working face where underground long hole fracturing is implemented, the first total dynamic load and the second total dynamic load.

[0021] To achieve the above-mentioned purpose, the third aspect embodiment of the present application proposes an electronic device, comprising: a processor, and a memory communicatively connected to the processor; the memory stores computer-executable instructions; the processor executes the computer-executable instructions stored in the memory to implement the method described in the first aspect.

[0022] To achieve the above-mentioned purpose, the fourth aspect of the present application proposes a computer-readable storage medium, in which computer-readable storage medium is stored computer-executable instructions, and when the computer-executable instructions are executed by a processor, they are used to implement the method described in the first aspect.

[0023] To achieve the above-mentioned purpose, the fifth aspect of the present application proposes a computer program product, including a computer program, which implements the method described in the first aspect when executed by a processor.

[0024] The present application provides a method, device, electronic device and storage medium for analyzing the load reduction and modification of thick hard roof in coal mine mining area by underground long hole fracturing to prevent and control rock burst. By establishing a model of the thick hard roof structure and dynamic load transfer engineering structure of the mining area before and after underground long hole fracturing, the leading static load stress of the working face before underground long hole fracturing, the first total dynamic load transmitted to the working face by the dynamic load formed when the multi-layer thick hard roof is periodically broken before underground long hole fracturing, and the second total dynamic load transmitted to the working face by the dynamic load formed when the multi-layer thick hard roof is periodically broken after underground long hole fracturing are performed; based on the above analysis and calculation process and The calculation results illustrate the transmission path of the thick hard roof breaking dynamic load before and after downhole long-hole fracturing and the weakening effect of downhole long-hole fracturing on the thick hard roof breaking dynamic load, analyze the transmission law of the thick hard roof breaking dynamic load, and quantitatively characterize the transmitted dynamic load; by analyzing and clarifying the weakening and modification effect of downhole long-hole fracturing on the strength of the thick hard roof, the weakening effect on the thick hard roof breaking dynamic load, and the attenuation effect on the thick hard roof breaking dynamic load during the transmission process in the fracturing artificial fracture network area, the principle of downhole long-hole fracturing load reduction and modification to prevent and control rock burst on thick hard roof is explained; it has important theoretical and practical significance for improving the effect of downhole long-hole fracturing on preventing and controlling rock burst on thick hard roof and promoting the application of this technology.

[0025] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0027] Figure 1 A schematic flow chart of an analysis method for underground long-hole fracturing load reduction and modification to prevent rock burst in a thick hard roof of a coal mine provided in an embodiment of the present application;

[0028] Figure 2 A schematic diagram of a downhole long hole fracturing of a thick hard roof provided in an embodiment of the present application;

[0029] Figure 3 A schematic diagram of the structure of the overburden rock before the periodic fracturing of the thick hard roof without downhole long hole fracturing provided in the embodiment of the present application;

[0030] Figure 4 A schematic diagram of the overburden structure and dynamic load transfer when the thick hard roof is periodically broken without downhole long hole fracturing provided in an embodiment of the present application;

[0031] Figure 5 A schematic diagram of the overburden structure and dynamic load transfer during the periodic breaking of the thick hard roof after downhole long hole fracturing provided in an embodiment of the present application;

[0032] Figure 6 A block diagram of an underground long-hole fracturing load reduction modification and prevention and control of rock burst analysis device for thick hard roof in a coal mine provided in an embodiment of the present application;

[0033] Figure 7 A block diagram of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0034] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0035] The following describes the analysis method, device and equipment for preventing and controlling rock burst by underground long-hole fracturing and load reduction modification of thick hard roof in a coal mine according to an embodiment of the present application with reference to the accompanying drawings.

[0036] Figure 1 A schematic flow chart of an analysis method for underground long-hole fracturing and load reduction modification to prevent and control rock burst in thick hard roof of a coal mine provided in an embodiment of the present application.

[0037] It should be noted that the executor of the method for analyzing the underground long hole fracturing and load reduction and modification for preventing and controlling rock burst in the thick hard roof of a coal mine in the embodiment of the present application is the underground long hole fracturing and load reduction and modification for preventing and controlling rock burst in the thick hard roof of a coal mine in the embodiment of the present application. The underground long hole fracturing and load reduction and modification for preventing and controlling rock burst in the thick hard roof of a coal mine can be configured in an electronic device so that the electronic device can execute the function of analyzing the underground long hole fracturing and load reduction and modification for preventing and controlling rock burst in the thick hard roof of a coal mine.

[0038] like Figure 1 As shown, the underground long hole fracturing load reduction modification and prevention and control of rock burst in the thick hard roof of the coal mine includes the following steps:

[0039] Step S101, respectively establishing a thick hard roof structure and a dynamic load transfer engineering structure model on a mining field where no downhole long hole fracturing is performed and a thick hard roof structure and a dynamic load transfer engineering structure model on a mining field where downhole long hole fracturing is performed.

[0040] It can be understood that the thick hard roof structure overlying the mining area and its fracture dynamic load transfer characteristics have a significant impact on the rock burst. In order to quantitatively analyze the impact of the dynamic load transfer characteristics of the thick hard roof overlying the mining area without and with underground long-hole fracturing on the rock burst, it is necessary to establish a structural model of the thick hard roof structure and dynamic load transfer engineering structure over the mining area without and with underground long-hole fracturing, and a structural model of the thick hard roof structure and dynamic load transfer engineering structure over the mining area with underground long-hole fracturing. Based on the model, the principle of load reduction and modification of thick hard roof in coal mining area by underground long-hole fracturing can be clarified to improve the effect of underground long-hole fracturing on thick hard roof to prevent and control rock burst, and at the same time provide support for the promotion and application of this technology.

[0041] It should be noted that underground long-hole fracturing is to construct horizontal directional drilling at a certain height from the underground tunnel to the coal seam roof, including the inclination section and the horizontal section. The horizontal section is arranged in the target rock layer to be fractured. The backward staged fracturing can achieve large-scale regional pressure relief and weakening of the thick hard roof, thereby reducing the strength of the thick hard roof. Figure 2 shown.

[0042] For example, based on the lithology revealed by typical borehole columns in the working face of a rock burst mine, a model of the thick hard roof structure and dynamic load transfer engineering structure over the mining area without underground long-hole fracturing and a model of the thick hard roof structure and dynamic load transfer engineering structure over the mining area with underground long-hole fracturing were established respectively.

[0043] Step S102, based on the thick hard roof structure overlying the mining area where no downhole long hole fracturing is implemented and the dynamic load transfer engineering structure model, calculate the first total dynamic load transmitted to the working face by the advanced static load stress of the working face where no downhole long hole fracturing is implemented and the dynamic load formed when the multi-layer thick hard roof is periodically broken where no downhole long hole fracturing is implemented.

[0044] It should be noted that after the initial breakage, the thick hard roof of the working face will break periodically as the working face continues to be mined. Since the thick hard roof has not been subjected to underground long-hole fracturing to relieve pressure, the thick hard roof forms a cantilever beam structure during the mining process of the working face. The existence of multiple layers of thick hard roof cantilever structures on the mining site causes a high stress concentration in front of the working face, which is easy to induce rock burst under dynamic loads. The overburden structure of the thick hard roof before periodic breakage without underground long-hole fracturing is shown in the figure below. Figure 3 shown.

[0045] As an implementation method, based on the thick hard roof structure and dynamic load transfer engineering structure model of the mining area where no underground long-hole fracturing is implemented, the limit equilibrium theory is used to analyze the distribution of the leading static load stress of the working face, and the leading static load stress of the working face where no underground long-hole fracturing is implemented is obtained.

[0046] The magnitude and distribution of the static load stress formed in front of the working face are related to factors such as the mining depth, mining height, and rock properties of the thick hard roof. The limit equilibrium theory can be used to analyze the distribution of the leading static load stress of the working face to obtain the leading static load stress distribution in the limit equilibrium zone and the elastic zone.

[0047] In some embodiments, the leading static load stress of the working surface can be calculated by the following formula:

[0048]

[0049] Among them, σ a is the leading static load stress of the working face; δ is the triaxial stress coefficient; P is the support resistance of the working face; c, are the cohesion and internal friction angle of the coal body respectively; f is the friction coefficient of the contact surface between the coal seam and the roof and floor plates; m is the mining height of the working face; x is the distance from any point in front of the working face to the coal wall; x0 is the width of the limit equilibrium zone; K′ is the stress concentration coefficient; γ is the bulk density of the rock formation; H is the mining depth of the working face; λ is the lateral pressure coefficient.

[0050] As the working face continues to be mined, the thick hard roof breaks under the overburden load. At this time, the thick hard roof breaks and generates dynamic load stress waves, which propagate along a certain path. The overburden structure and dynamic load transfer when the thick hard roof breaks periodically without downhole long hole fracturing are shown in the figure below. Figure 4 shown.

[0051] by Figure 4Taking the overburden structure of the thick hard roof periodic fracture without downhole long hole fracturing as an example, the leading static load stress σ of the working face of the thick hard roof without downhole long hole fracturing can be calculated by the above formula (1). s .

[0052] As an implementation method, a method for obtaining a first total dynamic load transmitted to a working face by a dynamic load generated when a multi-layer thick hard roof plate is periodically broken without downhole long hole fracturing includes:

[0053] Based on the thick hard roof structure and dynamic load transfer engineering structure model of the mining field where no downhole long hole fracturing is implemented, the overlying rock load of each layer of thick hard roof without downhole long hole fracturing, the propagation distance of the shock wave formed when the each layer of thick hard roof without downhole long hole fracturing is periodically broken, and the periodic breaking step distance of each layer of thick hard roof without downhole long hole fracturing are obtained;

[0054] Based on the overlying strata load of each layer of thick hard top plate without downhole long hole fracturing, the propagation distance of the shock wave formed when the each layer of thick hard top plate without downhole long hole fracturing is periodically broken, the periodic breaking step of each layer of thick hard top plate without downhole long hole fracturing, and the attenuation index of the propagation of the shock wave formed when the each layer of thick hard top plate without downhole long hole fracturing is periodically broken, the dynamic load formed when the each layer of thick hard top plate without downhole long hole fracturing is periodically broken and transmitted to the working face is obtained;

[0055] The dynamic loads generated when each layer of thick hard roof plate is periodically broken without downhole long hole fracturing are summed up and transmitted to the working face, so as to obtain the first total dynamic load generated when multiple layers of thick hard roof plate are periodically broken without downhole long hole fracturing and transmitted to the working face.

[0056] by Figure 4 Taking the overburden structure when the thick hard roof is broken periodically without downhole long hole fracturing as an example, according to the dynamic load formed when the thick hard roof is broken periodically and its transmission law, it can be obtained that the loads transferred to the working face by the dynamic loads formed when the sub-key layers Ⅰ, Ⅱ, and Ⅲ are broken without downhole long hole fracturing are:

[0057]

[0058] Among them, q z1 ,q z2 ,q z3 are the overlying rock loads of sub-critical layers Ⅰ, Ⅱ, and Ⅲ without downhole long-hole fracturing; L z1 , L z2 , L z3 are the periodic fracture steps of sub-critical layers Ⅰ, Ⅱ, and Ⅲ without downhole long-hole fracturing; r z1 、r z2 、r z3They are the propagation distances of the shock waves generated when sub-critical layers Ⅰ, Ⅱ, and Ⅲ are broken.

[0059] It should be noted here that the subcritical layer refers to the thick hard roof that plays a key role in controlling the breaking and movement of the overlying local roof. The subcritical layer is a specific layer of thick hard roof, and thick hard roof is a relatively broad expression.

[0060] According to the above analysis, the first total dynamic load generated by the periodic fracture of each thick hard roof without downhole long hole fracturing is transmitted to the working face:

[0061]

[0062] Thus, the first total dynamic load transmitted to the working face by the dynamic load generated when each thick hard roof plate is periodically broken without downhole long hole fracturing is obtained.

[0063] Step S103, based on the thick hard roof structure overlying the mining area where downhole long hole fracturing is implemented and the dynamic load transfer engineering structure model, calculate the advanced static load stress of the working face where downhole long hole fracturing is implemented and the second total dynamic load transferred to the working face by the dynamic load formed when the multiple layers of thick hard roof are periodically broken when downhole long hole fracturing is implemented.

[0064] It should be noted that due to the implementation of underground long-hole fracturing to relieve pressure on the thick hard roof, the strength of the thick hard roof was weakened, its integrity was reduced, and the thick hard rock layer was modified. Therefore, during the mining process of the working face, the overburden in the mining area can be broken and collapsed in time. When the thick hard roof is broken, a dynamic load stress wave is generated and propagates along a certain path. The overburden structure and the dynamic load transfer formed when the thick hard roof is periodically broken by underground long-hole fracturing are shown in the figure below. Figure 5 shown.

[0065] As an implementation method, a method for calculating the second total dynamic load transmitted to the working face by the dynamic load generated when the multi-layer thick hard roof plate is periodically broken during downhole long hole fracturing is implemented; comprising:

[0066] Based on the thick hard roof structure and dynamic load transfer engineering structure model of the mining area where long hole fracturing is implemented, the overlying rock load of each layer of thick hard roof where long hole fracturing is implemented, the propagation distance of the shock wave formed when each layer of thick hard roof where long hole fracturing is implemented is obtained, and the periodic breaking step distance of each layer of thick hard roof where long hole fracturing is implemented is obtained;

[0067] Based on the overlying strata load of each thick hard top plate during downhole long hole fracturing, the propagation distance of the shock wave formed when each thick hard top plate during downhole long hole fracturing is periodically broken, the periodic breaking step of each thick hard top plate during downhole long hole fracturing, and the attenuation index of the propagation of the shock wave formed when each thick hard top plate during downhole long hole fracturing is periodically broken, the dynamic load formed when each thick hard top plate during downhole long hole fracturing is periodically broken and transmitted to the working face is obtained;

[0068] The dynamic loads generated when each layer of thick hard top plate is periodically broken during downhole long hole fracturing and transferred to the working face are summed to obtain the second total dynamic load generated when multiple layers of thick hard top plate are periodically broken during downhole long hole fracturing and transferred to the working face.

[0069] by Figure 5 Taking the overburden structure when the thick hard roof is broken during the downhole long hole fracturing as an example, the leading static load stress σ of the working face for downhole long hole fracturing of the thick hard roof can be calculated by the above formula (1). s ′.

[0070] by Figure 5 Taking the overburden structure when the thick hard roof is broken periodically during downhole long hole fracturing as an example, similarly, the loads transmitted to the working face by the dynamic loads generated when the thick hard key layers Ⅰ, Ⅱ, and Ⅲ are broken during downhole long hole fracturing are:

[0071]

[0072] Among them, q′ z1 ,q′ z2 ,q′ z3 are the overlying rock loads of sub-critical layers Ⅰ, Ⅱ, and III for downhole long-hole fracturing; L′ z1 , L′ z2 , L′ z3 are the periodic breaking step lengths of sub-critical layers Ⅰ, Ⅱ and III for downhole long-hole fracturing; β′1, β′2 and β′3 are the attenuation indexes of vibration wave propagation formed by the breaking of sub-critical layers Ⅰ, Ⅱ and III for downhole long-hole fracturing.

[0073] According to the above analysis, the total dynamic load transmitted to the working face by the dynamic load generated by the periodic fracture of each thick hard roof during downhole long hole fracturing is:

[0074]

[0075] Thus, the total dynamic load transmitted to the working face by the dynamic load generated when each thick hard roof plate is periodically broken during downhole long hole fracturing is obtained.

[0076] Step S104, based on the advanced static load stress of the working face without underground long hole fracturing, the advanced static load stress of the working face with underground long hole fracturing, the first total dynamic load and the second total dynamic load, the analysis results of underground long hole fracturing load reduction and modification for preventing and controlling rock burst in thick hard roof of coal mine are obtained.

[0077] Through analysis, it can be seen that after implementing downhole long-hole fracturing in the thick hard rock layer overlying the mining area, a large number of artificial fracture networks can be formed in the thick hard rock layer, which significantly reduces the strength of the thick hard roof. After the working face is mined, the thick hard roof can be broken in time, avoiding the large-area hanging roof and forming static load stress concentration. At the same time, it can effectively reduce the breaking step of the thick hard roof and significantly reduce the breaking dynamic load of the thick hard roof. At the same time, the large number of mesh cracks with different orientations and lengths formed in the thick hard roof reduce the integrity of the thick hard roof, realize the modification of the thick hard rock layer, and have a good absorption effect on the dynamic load formed by the roof breaking during the transmission process, that is, the fractured rock layer after the downhole long-hole fracturing has an attenuation effect on the transmission of vibration waves. The implementation of downhole long-hole fracturing can reduce the disturbance intensity of the dynamic load formed by the breaking of the thick hard roof from the source, increase its attenuation degree during the dynamic load transmission process, and finally make the dynamic load transmitted to the working face or tunnel significantly reduced compared with the case when the downhole long-hole fracturing is not implemented. After implementing underground long-hole fracturing on the thick hard roof overlying the mining area, the total stress on the working face or tunnel surrounding rock can be lowered than the critical stress of impact instability of the coal rock mass, thereby reducing the impact risk and achieving effective control of rock burst pressure.

[0078] The total load σ on the working face without downhole long hole fracturing in the thick hard roof includes the working face leading static load stress σ s The total dynamic load σ transmitted to the working face when the thick hard roof is broken periodically without downhole long hole fracturing d , that is, σ=σ s +σ d The total load σ′ on the working face of downhole long-hole fracturing in thick hard roof includes the leading static load stress σ s ′ and the total dynamic load σ′ generated when each thick hard roof plate is broken periodically during downhole long hole fracturing and transmitted to the working face d , that is, σ′=σ s ′+σ′ d The rock burst condition for thick hard roof without downhole long hole fracturing is that the total load σ on the working face is greater than the critical stress σ of coal rock mass rock burst instability b , that is, σ>σ b The condition for no rock burst during long hole fracturing in thick hard roof is that the total load σ′ on the working face is less than the critical stress σ of coal rock mass rock burst instability. b , that is, σ′<σ b .

[0079] The method for analyzing underground long-hole fracturing to prevent and control rock burst in thick hard roof of coal mine in the embodiment of the present application establishes a model of the thick hard roof structure and dynamic load transfer engineering structure of the mine before and after underground long-hole fracturing. Based on the model, the leading static load stress of the working face before underground long-hole fracturing is implemented, the first total dynamic load transmitted to the working face by the dynamic load formed when the multi-layer thick hard roof is periodically broken before underground long-hole fracturing is implemented, and the second total dynamic load transmitted to the working face by the dynamic load formed when the multi-layer thick hard roof is periodically broken after underground long-hole fracturing is implemented; based on the above analysis and calculation process and calculation results, it is explained The transmission path of the thick hard roof breaking dynamic load before and after downhole long-hole fracturing and the weakening effect of downhole long-hole fracturing on the thick hard roof breaking dynamic load were studied. The transmission law of the thick hard roof breaking dynamic load was analyzed, and the transmitted dynamic load was quantitatively characterized. The weakening and modification effect of downhole long-hole fracturing on the strength of the thick hard roof, the weakening effect on the thick hard roof breaking dynamic load, and the attenuation effect on the thick hard roof breaking dynamic load during the transmission process in the artificial fracture network area of ​​the fracturing were clarified by analyzing and clarifying the downhole long-hole fracturing on the thick hard roof strength. The principle of downhole long-hole fracturing load reduction and modification for preventing and controlling rock burst in thick hard roof was explained. It has important theoretical and practical significance for improving the effect of downhole long-hole fracturing on preventing and controlling rock burst in thick hard roof and promoting the application of this technology.

[0080] In order to realize the above-mentioned embodiment, the present application also proposes an underground long-hole fracturing and rock burst analysis device for thick hard roof in coal mines. Figure 6 This is a block diagram of a device for analyzing underground long-hole fracturing to prevent rock burst in a coal mine with thick hard roof provided in an embodiment of the present application. Figure 6 As shown, the underground long hole fracturing device for preventing and controlling rock burst in thick hard roof of a coal mine may include: a model acquisition module 201 , a load calculation module 202 and a load analysis module 203 .

[0081] The model acquisition module 201 is used to respectively establish a model of a thick hard roof structure and a dynamic load transfer engineering structure on a mining site where downhole long hole fracturing is not performed and a model of a thick hard roof structure and a dynamic load transfer engineering structure on a mining site where downhole long hole fracturing is performed;

[0082] The load calculation module 202 is used to calculate the leading static load stress of the working face without downhole long hole fracturing and the first total dynamic load transmitted to the working face by the dynamic load formed when the multi-layer thick hard roof plate is periodically broken without downhole long hole fracturing, based on the thick hard roof structure overlying the mining field without downhole long hole fracturing and the dynamic load transfer engineering structure model;

[0083] The load calculation module 202 is further used to calculate the leading static load stress of the working face for downhole long hole fracturing and the second total dynamic load transmitted to the working face by the dynamic load formed when the multi-layer thick hard roof plate is periodically broken during downhole long hole fracturing based on the thick hard roof structure overlying the mining field for downhole long hole fracturing and the dynamic load transfer engineering structure model;

[0084] The load analysis module 203 is used to analyze and obtain the rock burst analysis results of underground long hole fracturing for preventing and controlling the thick hard roof of a coal mine based on the advanced static load stress of the working face where underground long hole fracturing is not implemented, the advanced static load stress of the working face where underground long hole fracturing is implemented, the first total dynamic load, and the second total dynamic load.

[0085] Further, in a possible implementation of the embodiment of the present application, the load calculation module 202 calculates the leading static load stress of the working face where downhole long hole fracturing is not implemented based on the thick hard roof structure and the dynamic load transfer engineering structure model on the mining field where downhole long hole fracturing is not implemented;

[0086] Based on the thick hard roof structure and dynamic load transfer engineering structure model of the mining area without underground long-hole fracturing, the limit equilibrium theory is used to analyze the distribution of the leading static load stress of the working face, and the leading static load stress of the working face without underground long-hole fracturing is obtained.

[0087] Further, in a possible implementation of the embodiment of the present application, the advance static load stress of the working surface where downhole long hole fracturing is not performed is calculated by a first formula, which is expressed as follows:

[0088]

[0089] Among them, σ a is the leading static load stress of the working face; δ is the triaxial stress coefficient; P is the support resistance of the working face; c, are the cohesion and internal friction angle of the coal body respectively; f is the friction coefficient of the contact surface between the coal seam and the roof and floor plates; m is the mining height of the working face; x is the distance from any point in front of the working face to the coal wall; x0 is the width of the limit equilibrium zone; K′ is the stress concentration coefficient; γ is the bulk density of the rock formation; H is the mining depth of the working face; λ is the lateral pressure coefficient.

[0090] Further, in a possible implementation of the embodiment of the present application, the load calculation module 202 calculates the first total dynamic load transmitted to the working face by the dynamic load generated when the multi-layer thick hard roof is periodically broken without the downhole long hole fracturing based on the overlying thick hard roof structure and the dynamic load transfer engineering structure model of the stope without the downhole long hole fracturing;

[0091] Based on the thick hard roof structure and dynamic load transfer engineering structure model of the mining field where no downhole long hole fracturing is implemented, the overlying rock load of each layer of thick hard roof without downhole long hole fracturing, the propagation distance of the shock wave formed when the each layer of thick hard roof without downhole long hole fracturing is periodically broken, and the periodic breaking step distance of each layer of thick hard roof without downhole long hole fracturing are obtained;

[0092] Based on the overlying strata load of each layer of thick hard top plate without downhole long hole fracturing, the propagation distance of the shock wave formed when the each layer of thick hard top plate without downhole long hole fracturing is periodically broken, the periodic breaking step of each layer of thick hard top plate without downhole long hole fracturing, and the attenuation index of the propagation of the shock wave formed when the each layer of thick hard top plate without downhole long hole fracturing is periodically broken, the dynamic load formed when the each layer of thick hard top plate without downhole long hole fracturing is periodically broken and transmitted to the working face is obtained;

[0093] The dynamic loads generated when each layer of thick hard roof plate is periodically broken without downhole long hole fracturing are summed up and transmitted to the working face, so as to obtain the first total dynamic load generated when multiple layers of thick hard roof plate are periodically broken without downhole long hole fracturing and transmitted to the working face.

[0094] Further, in a possible implementation of the embodiment of the present application, the dynamic load generated when each layer of thick hard top plate is periodically broken without downhole long hole fracturing is transferred to the working surface by the second formula, which is expressed as follows:

[0095]

[0096] Among them, q z1 ,q z2 ,q z3 are the overlying rock loads of sub-critical layers Ⅰ, Ⅱ, and Ⅲ without downhole long-hole fracturing; L z1 , L z2 , L z3 are the periodic fracture steps of sub-critical layers Ⅰ, Ⅱ, and Ⅲ without downhole long-hole fracturing; r z1 、r z2 、r z3 are the propagation distances of the shock waves generated when the sub-critical layers Ⅰ, Ⅱ, and III are broken; β1, β2, and β3 are the attenuation indexes of the shock wave propagation generated when the sub-critical layers Ⅰ, Ⅱ, and III are broken without downhole long-hole fracturing.

[0097] Further, in a possible implementation of the embodiment of the present application, the load calculation module 202 calculates the second total dynamic load transmitted to the working face by the dynamic load generated when the multi-layer thick hard roof plate is periodically broken for implementing downhole long hole fracturing based on the thick hard roof plate structure overlying the stope for implementing downhole long hole fracturing and the dynamic load transfer engineering structure model; and is used to:

[0098] Based on the thick hard roof structure and dynamic load transfer engineering structure model of the mining area where long hole fracturing is implemented, the overlying rock load of each layer of thick hard roof where long hole fracturing is implemented, the propagation distance of the shock wave formed when each layer of thick hard roof where long hole fracturing is implemented is obtained, and the periodic breaking step distance of each layer of thick hard roof where long hole fracturing is implemented is obtained;

[0099] Based on the overlying strata load of each thick hard top plate during downhole long hole fracturing, the propagation distance of the shock wave formed when each thick hard top plate during downhole long hole fracturing is periodically broken, the periodic breaking step of each thick hard top plate during downhole long hole fracturing, and the attenuation index of the propagation of the shock wave formed when each thick hard top plate during downhole long hole fracturing is periodically broken, the dynamic load formed when each thick hard top plate during downhole long hole fracturing is periodically broken and transmitted to the working face is obtained;

[0100] The dynamic loads generated when each layer of thick hard top plate is periodically broken during downhole long hole fracturing and transferred to the working face are summed to obtain the second total dynamic load generated when multiple layers of thick hard top plate are periodically broken during downhole long hole fracturing and transferred to the working face.

[0101] Furthermore, in a possible implementation of the embodiment of the present application, the load analysis module 203 is specifically configured to:

[0102] Based on the advanced static load stress of the working face where downhole long hole fracturing is not implemented, the advanced static load stress of the working face where downhole long hole fracturing is implemented, the first total dynamic load and the second total dynamic load, the total load on the working face where downhole long hole fracturing is not implemented and the total load on the working face where downhole long hole fracturing is implemented are obtained;

[0103] Obtain the critical stress of coal rock mass impact instability;

[0104] Based on the total load on the working face without downhole long-hole fracturing, the total load on the working face with downhole long-hole fracturing and the critical stress of coal rock impact instability, the conditions for the occurrence of rock burst when downhole long-hole fracturing is not implemented on the thick hard roof and the conditions for the non-occurrence of rock burst when downhole long-hole fracturing is implemented on the thick hard roof are obtained.

[0105] It should be noted that the aforementioned explanation of the embodiment of the method for analyzing the underground long hole fracturing for preventing and controlling rock burst in thick and hard roof of coal mines is also applicable to the device for analyzing the underground long hole fracturing for preventing and controlling rock burst in thick and hard roof of coal mines of this embodiment, and will not be repeated here.

[0106] In order to implement the above embodiment, the present application also proposes an electronic device. Figure 7 , Figure 7 is a block diagram of an electronic device provided in an embodiment of the present application. Figure 7 As shown, the electronic device 700 includes: a processor 701, and a memory 702 communicatively connected to the processor 701; the memory 702 stores computer-executable instructions; the processor 701 executes the computer-executable instructions stored in the memory to implement the method provided in the aforementioned embodiment.

[0107] In order to implement the above embodiments, the present application also proposes a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, they are used to implement the methods provided by the above embodiments.

[0108] In order to implement the above embodiments, the present application also proposes a computer program product, including a computer program, which implements the methods provided by the above embodiments when executed by a processor.

[0109] In the description of the aforementioned embodiments, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0110] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0111] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or more executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

[0112] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or more wires (electronic devices), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), a fiber optic device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways if necessary, and then stored in a computer memory.

[0113] It should be understood that the various parts of the present application can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0114] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

[0115] In addition, each functional unit in each embodiment of the present application may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0116] The storage medium mentioned above may be a read-only memory, a magnetic disk or an optical disk, etc. Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the present application. A person of ordinary skill in the art may change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A method for analyzing underground long-hole fracturing load reduction and modification for preventing and controlling rock burst in thick hard roof of coal mine, characterized in that: The following steps are involved: The thick hard roof structure and dynamic load transfer engineering structure model of the mining field without downhole long hole fracturing and the thick hard roof structure and dynamic load transfer engineering structure model of the mining field with downhole long hole fracturing were established respectively; Based on the thick hard roof structure overlying the mining field where no downhole long hole fracturing is implemented and the dynamic load transfer engineering structure model, the leading static load stress of the working face where no downhole long hole fracturing is implemented and the first total dynamic load transmitted to the working face by the dynamic load formed when the multi-layer thick hard roof is periodically broken where no downhole long hole fracturing is implemented are calculated; Based on the thick hard roof structure overlying the mining area where downhole long hole fracturing is implemented and the dynamic load transfer engineering structure model, the leading static load stress of the working face where downhole long hole fracturing is implemented and the second total dynamic load transmitted to the working face by the dynamic load formed when the multi-layer thick hard roof is periodically broken during downhole long hole fracturing are calculated; Based on the advance static load stress of the working face where underground long hole fracturing is not implemented, the advance static load stress of the working face where underground long hole fracturing is implemented, the first total dynamic load and the second total dynamic load, the analysis results of underground long hole fracturing for preventing and controlling rock burst in thick hard roof of coal mine are obtained.

2. The method according to claim 1, characterized in that The method of calculating the advanced static load stress of the working face where downhole long hole fracturing is not implemented based on the thick hard roof structure and the dynamic load transfer engineering structure model of the stope where downhole long hole fracturing is not implemented; comprising: Based on the thick hard roof structure overlying the mining area where no underground long hole fracturing is implemented and the dynamic load transfer engineering structure model, the limit equilibrium theory is used to analyze the distribution of the leading static load stress of the working face, and the leading static load stress of the working face where no underground long hole fracturing is implemented is obtained.

3. The method according to claim 2, characterized in that The leading static load stress of the working surface is calculated by a first formula, which is expressed as follows: Among them, σ a is the leading static load stress of the working face; δ is the triaxial stress coefficient; P is the support resistance of the working face; c, are the cohesion and internal friction angle of the coal body respectively; f is the friction coefficient of the contact surface between the coal seam and the roof and floor plates; m is the mining height of the working face; x is the distance from any point in front of the working face to the coal wall; x0 is the width of the limit equilibrium zone; K′ is the stress concentration coefficient; γ is the bulk density of the rock formation; H is the mining depth of the working face; λ is the lateral pressure coefficient.

4. The method according to claim 1, characterized in that: The method, based on the thick hard roof structure overlying the mining field where no downhole long hole fracturing is implemented and the dynamic load transfer engineering structure model, calculates the first total dynamic load transmitted to the working face by the dynamic load generated when the multi-layer thick hard roof is periodically broken without downhole long hole fracturing; including: Based on the thick hard roof structure overlying the mining field where no downhole long hole fracturing is implemented and the dynamic load transfer engineering structure model, the overlying rock stratum load of each layer of thick hard roof where no downhole long hole fracturing is implemented, the propagation distance of the shock wave formed when each layer of thick hard roof where no downhole long hole fracturing is implemented is obtained when the periodic fracture of each layer of thick hard roof where no downhole long hole fracturing is implemented, and the periodic fracture step distance of each layer of thick hard roof where no downhole long hole fracturing is implemented; Based on the overlying strata load of each layer of thick hard top plate without downhole long hole fracturing, the propagation distance of the shock wave formed when the each layer of thick hard top plate without downhole long hole fracturing is periodically broken, the periodic breaking step of each layer of thick hard top plate without downhole long hole fracturing, and the attenuation index of the propagation of the shock wave formed when the each layer of thick hard top plate without downhole long hole fracturing is periodically broken, the dynamic load formed when the each layer of thick hard top plate without downhole long hole fracturing is periodically broken and transmitted to the working face is obtained; The dynamic loads generated when the layers of thick hard top plates are periodically broken without implementing downhole long-hole fracturing and transferred to the working face are summed to obtain the first total dynamic load generated when the layers of thick hard top plates are periodically broken without implementing downhole long-hole fracturing and transferred to the working face.

5. The method according to claim 4, characterized in that The dynamic load generated when the thick hard roof layers without downhole long hole fracturing are periodically broken and transmitted to the working surface is calculated by the second formula, which is expressed as follows: Among them, q z1 ,q z2 ,q z3 are the overlying rock loads of sub-critical layers Ⅰ, Ⅱ, and Ⅲ without downhole long-hole fracturing; L z1 , L z2 , L z3 are the periodic fracture steps of sub-critical layers Ⅰ, Ⅱ, and Ⅲ without downhole long-hole fracturing; r z1 、r z2 、r z3 are the propagation distances of the shock waves generated when the sub-critical layers Ⅰ, Ⅱ, and III are broken; β1, β2, and β3 are the attenuation indexes of the shock wave propagation generated when the sub-critical layers Ⅰ, Ⅱ, and III are broken without downhole long-hole fracturing.

6. The method according to claim 1, characterized in that The method is based on the thick hard roof structure overlying the mining area where the downhole long hole fracturing is implemented and the dynamic load transfer engineering structure model, and calculates the second total dynamic load transmitted to the working face by the dynamic load generated when the multi-layer thick hard roof is periodically broken during the downhole long hole fracturing; including: Based on the thick hard roof structure overlying the mining area where the downhole long hole fracturing is implemented and the dynamic load transfer engineering structure model, the overlying rock stratum load of each layer of thick hard roof for downhole long hole fracturing, the propagation distance of the shock wave formed when each layer of thick hard roof for downhole long hole fracturing is periodically broken, and the periodic breaking step distance of each layer of thick hard roof for downhole long hole fracturing are obtained; Based on the overlying strata load of each thick hard top plate during the downhole long hole fracturing, the propagation distance of the shock wave formed when each thick hard top plate during the downhole long hole fracturing is periodically broken, the periodic breaking step of each thick hard top plate during the downhole long hole fracturing, and the attenuation index of the propagation of the shock wave formed when each thick hard top plate during the downhole long hole fracturing is periodically broken, the dynamic load formed when each thick hard top plate during the downhole long hole fracturing is periodically broken and transmitted to the working face is obtained; The dynamic loads generated when each layer of thick hard top plate is periodically broken during the downhole long hole fracturing and transferred to the working surface are summed to obtain a second total dynamic load generated when multiple layers of thick hard top plate are periodically broken during the downhole long hole fracturing and transferred to the working surface.

7. The method according to claim 1, characterized in that The analysis result of underground long hole fracturing for preventing and controlling rock burst in thick hard roof of coal mine field is obtained by analyzing the advanced static load stress of the working face where underground long hole fracturing is not implemented, the advanced static load stress of the working face where underground long hole fracturing is implemented, the first total dynamic load and the second total dynamic load; including: Based on the advanced static load stress of the working face where downhole long hole fracturing is not implemented, the advanced static load stress of the working face where downhole long hole fracturing is implemented, the first total dynamic load, and the second total dynamic load, the total load on the working face where downhole long hole fracturing is not implemented and the total load on the working face where downhole long hole fracturing is implemented are obtained; Obtain the critical stress of coal rock mass impact instability; Based on the total load on the working face where no downhole long-hole fracturing is implemented, the total load on the working face where downhole long-hole fracturing is implemented and the critical stress of impact instability of the coal rock mass, the conditions for the occurrence of rock burst when downhole long-hole fracturing is not implemented on the thick hard roof and the conditions for no rock burst when downhole long-hole fracturing is implemented on the thick hard roof are obtained.

8. An underground long hole fracturing device for preventing and controlling rock burst in thick hard roof of coal mine, characterized in that: include: A model acquisition module is used to respectively establish a model of a thick hard roof structure and a dynamic load transfer engineering structure on a mining site where no downhole long hole fracturing is implemented and a model of a thick hard roof structure and a dynamic load transfer engineering structure on a mining site where downhole long hole fracturing is implemented; A load calculation module, for calculating the first total dynamic load transmitted to the working face by the advanced static load stress of the working face where the downhole long hole fracturing is not implemented and the dynamic load formed when the multi-layer thick hard roof is periodically broken where the downhole long hole fracturing is not implemented, based on the thick hard roof structure overlying the mining field where the downhole long hole fracturing is not implemented and the dynamic load transfer engineering structure model; The load calculation module is further used to calculate the leading static load stress of the working face for implementing downhole long hole fracturing and the second total dynamic load transmitted to the working face by the dynamic load formed when the multi-layer thick hard roof plate is periodically broken for implementing downhole long hole fracturing, based on the thick hard roof plate structure overlying the mining field for implementing downhole long hole fracturing and the dynamic load transfer engineering structure model; The load analysis module is used to analyze and obtain the impact ground pressure analysis results of underground long hole fracturing for preventing and controlling the thick hard roof of a coal mine based on the advanced static load stress of the working face where underground long hole fracturing is not implemented, the advanced static load stress of the working face where underground long hole fracturing is implemented, the first total dynamic load and the second total dynamic load.

9. An electronic device, characterized in that: include: A processor, and a memory communicatively connected to the processor; The memory stores computer-executable instructions; The processor executes the computer-executable instructions stored in the memory to implement the method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer-executable instructions, which are used to implement the method according to any one of claims 1 to 7 when executed by a processor.

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