A shallow-buried thin-base soft rock two-zone water prevention and control design method and system

Abstract

This invention discloses a design method and system for water control in shallow-buried, thin-bedded soft rock with two zones. It utilizes the fracture-sealing characteristics of the "two zones" structure of the rock strata after mining, and strengthens this structural feature through optimization of mining parameters and processes to achieve overall structural water inrush prevention. The main steps are as follows: (1) Investigation of coal seam occurrence conditions and overburden conditions; (2) Testing of basic physical and mechanical parameters of coal and rock samples; (3) Theoretical analysis to determine the conditions for timely bedrock fracture; (4) Design of working face mining parameters and retreat roadway support parameters; (5) Optimization of working face mining parameters and retreat roadway support parameters. The water control scheme designed and improved by this invention mainly utilizes the rock strata's own structure for water isolation, is low-cost, simple to operate, and easy to promote, possessing significant scientific and application value.

Description

Technical Field

[0001] This invention belongs to the field of coal mining, specifically relating to a design method and system for water prevention and control in shallow-buried, thin-foundation soft rock with two zones. Background Technology

[0002] Coal mining beneath aquifers has always been a key research area in the mining industry, leading to the development of relatively complete mine water control systems. However, the variability of coal mining conditions necessitates site-specific adjustments to water control methods for different mines. This invention discloses a design method that, through research and analysis of the overburden migration and fracture development patterns of shallow-buried, thin-bedded soft rock coal seams in western my country, abandons traditional water control methods such as drainage, grouting, and aquitard modification. Instead, it proposes a water control method based on the overall structural aquitard of the rock strata and presents a water control design method specifically for this type of mine. Summary of the Invention

[0003] To address the shortcomings of existing technologies, this invention proposes a design method and system for water control in shallow-buried, thin-foundation, soft rock with two zones. This provides a reference for designing water control methods for this type of mine under shallow-buried, thin-foundation, soft rock coal seam conditions, and significantly reduces the cost of mine water control.

[0004] To achieve the above objectives, the present invention provides the following solution:

[0005] A design method for water control in shallow-buried, thin-foundation soft rock with two zones includes the following steps:

[0006] Obtain coal seam occurrence conditions and overlying strata conditions;

[0007] Test the basic physical and mechanical parameters of coal and rock samples;

[0008] Based on the coal seam occurrence conditions, the overburden conditions, and the basic physical and mechanical parameters of the coal and rock samples, simulation and theoretical analysis are conducted to determine the conditions for timely bedrock fracture.

[0009] Based on the aforementioned bedrock fracture conditions, the working face mining parameters are obtained;

[0010] Based on the mining parameters of the working face, the support parameters of the mining roadway are optimized to complete the overall structural water inrush prevention of the rock strata.

[0011] Preferably, the coal seam occurrence conditions and overlying strata conditions include: the dip angle of the mine, the burial depth, the bedrock thickness, and the bedrock hardness;

[0012] Among them, the coal seam dip angle is less than 12°, the coal seam burial depth is less than 300m, the bedrock has a Protodyakonov hardness coefficient of less than 15 and weak cementation, and the bedrock thickness is less than 200m.

[0013] Preferred methods for testing the basic physical and mechanical parameters of coal and rock samples include:

[0014] Obtain a coal and rock sample of a predetermined volume;

[0015] The coal and rock samples were processed to obtain the tensile strength, compressive strength, shear strength, and hardness of the rock.

[0016] Preferably, the method for determining the conditions for timely bedrock fracture by simulation and theoretical analysis based on the coal seam occurrence conditions, the overburden conditions, and the basic physical and mechanical parameters of the coal and rock samples includes:

[0017] A theoretical mechanical model is established based on the coal seam occurrence conditions, the overburden conditions, and the basic physical and mechanical parameters of the coal and rock samples.

[0018] In the theoretical mechanics model, the bedrock is regarded as a composite beam with an elastic connection in the middle. The load on the upper part of the composite beam and the loose rock layer is equivalent to a uniformly distributed load. The coal seam below the composite beam is simplified as a Winkler elastic body. Dip model and strike model are established respectively.

[0019] Based on the aforementioned tendency model and the aforementioned direction model, calculations and analyses are performed by changing the surface length and the advancing step distance to determine the conditions for timely bedrock fracture. Among these, the bedrock reaching the ultimate bending moment is used as the criterion for fracture.

[0020] Preferably, during the mining process at the working face, the support elements that enhance the strength and integrity of the roof in the mining roadway are removed.

[0021] The present invention also provides a two-zone water control design system for shallow buried thin foundation soft rock, including: a condition acquisition module, a testing module, a discrimination module, a parameter acquisition module and an optimization module;

[0022] The condition acquisition module is used to acquire coal seam occurrence conditions and overlying strata conditions;

[0023] The testing module is used to test the basic physical and mechanical parameters of coal and rock samples;

[0024] The discrimination module is used to perform simulation and theoretical analysis based on the coal seam occurrence conditions, the overburden conditions and the basic physical and mechanical parameters of the coal and rock samples to determine the conditions for timely bedrock fracture.

[0025] The parameter acquisition module is used to obtain the working face mining parameters based on the timely fracture conditions of the bedrock;

[0026] The optimization module is used to optimize the support parameters of the mining roadway based on the mining parameters of the working face, thereby completing the overall structural water inrush prevention of the rock strata.

[0027] Preferably, the coal seam occurrence conditions and overlying strata conditions include: the dip angle of the mine, the burial depth, the bedrock thickness, and the bedrock hardness;

[0028] Among them, the coal seam dip angle is less than 12°, the coal seam burial depth is less than 300m, the bedrock has a Protodyakonov hardness coefficient of less than 15 and weak cementation, and the bedrock thickness is less than 200m.

[0029] Preferably, the process of testing the basic physical and mechanical parameters of coal and rock samples includes:

[0030] Obtain a coal and rock sample of a predetermined volume;

[0031] The coal and rock samples were processed to obtain the tensile strength, compressive strength, shear strength, and hardness of the rock.

[0032] Preferably, the process of determining the conditions for timely bedrock fracture through simulation and theoretical analysis based on the coal seam occurrence conditions, the overburden conditions, and the basic physical and mechanical parameters of the coal and rock samples includes:

[0033] A theoretical mechanical model is established based on the coal seam occurrence conditions, the overburden conditions, and the basic physical and mechanical parameters of the coal and rock samples.

[0034] In the theoretical mechanics model, the bedrock is regarded as a composite beam with an elastic connection in the middle. The load on the upper part of the composite beam and the loose rock layer is equivalent to a uniformly distributed load. The coal seam below the composite beam is simplified as a Winkler elastic body. Dip model and strike model are established respectively.

[0035] Based on the aforementioned tendency model and the aforementioned direction model, calculations and analyses are performed by changing the surface length and the advancing step distance to determine the conditions for timely bedrock fracture. Among these, the bedrock reaching the ultimate bending moment is used as the criterion for fracture.

[0036] Preferably, during the mining process at the working face, the support elements that enhance the strength and integrity of the roof in the mining roadway are removed.

[0037] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0038] This invention addresses the unique geological conditions of shallow-buried, thin-foundation, soft rock mines by proposing a water control method and system based on the overall structural water-blocking of the rock strata. It also presents a water control design method and system for this type of mine. The invention features clear steps, simple operation, reduces unnecessary water control measures, significantly lowers mine water control costs, and provides a reference for water control work in similar types of mines. Attached Figure Description

[0039] To more clearly illustrate the technical solution of the present invention, the drawings used in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1 This is a schematic diagram of the design principle of the present invention;

[0041] Figure 2 This is a design flowchart of the present invention;

[0042] Figure 3 This is a diagram of the bedrock physical model of the present invention;

[0043] Figure 4 This is a graph showing the relationship between the number of cycles and the surface length calculated for a certain mine in which this invention is applied;

[0044] Figure 5 This is a top view of the end support element of the present invention before removal;

[0045] Figure 6 This is a top view of the end support element of the present invention when it is removed;

[0046] Figure 7 This is a cross-sectional view of the roadway when the support element of the present invention is removed;

[0047] Figure 8 This is a cross-sectional view of the roadway after the protective components of the present invention have been removed;

[0048] Figure 9 This is a cross-sectional view of the roadway after the single support column of the present invention has been withdrawn.

[0049] In the diagram: Ⅰ-Collapse zone; Ⅱ-Overall subsidence zone; Ⅲ-Aquifer; 1-Closed fracture within the aquifer; 2-Non-penetrating fracture during aquifer subsidence; 3-Fractured and sealed fracture at the fracture point of the fractured rock strata; 4-Bedrock roof; 5-Direct roof; 6-Upper roadway; 7-Transition support; 8-Upper roadway end support; 9-Rear scraper conveyor; 10-Upper roadway advance support; 11-Single support; 12-Top anchor bolt and cable; 13-Side anchor cable; 14-Steel strip. Detailed Implementation

[0050] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0051] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0052] Example 1

[0053] The design principle of the "two-zone" water control design method for shallow-buried thin-foundation soft rock disclosed in this invention mainly includes: after the mining of shallow-buried thin-foundation soft rock, the rock strata form a "two-zone" structure, characterized by the existence of only a collapse zone and a subsidence zone with coordinated subsidence characteristics and fewer fractures (referred to here as the "overall subsidence zone"), while the internal aquifer remains relatively intact; at the same time, the rock strata as a whole slowly subside in an "inverted trapezoidal" shape, which has a sealing effect on the edge fractures, specifically as follows... Figure 1 As shown. This invention mainly utilizes this special rock stratum structure to prevent and control water inrush in the overall structure of the rock stratum. The core design idea is: (1) to ensure that the overburden of the working face collapses in time, shortening the development time and range of cracks in the bedrock; (2) to ensure the sinking direction and angle of the rock stratum, forming an overall "inverted trapezoidal" sinking.

[0054] This invention discloses a water control design method for shallow-buried, thin-bedded soft rock with two zones, comprising: (1) investigation of coal seam occurrence conditions and overburden conditions; (2) testing of basic physical and mechanical parameters of coal and rock samples; (3) simulation and theoretical analysis to determine the conditions for timely bedrock fracture; (4) design of working face mining parameters; and (5) optimization of support parameters for longwall roadways. The flowchart of the design method is shown below. Figure 2 As shown.

[0055] Step (1) The main contents of the investigation of coal seam occurrence conditions and overlying strata conditions include: investigating the dip angle, burial depth, bedrock thickness, and bedrock hardness of the mine. This method is for working face mining design under special conditions. The proposed working face to be mined must meet the following conditions: coal seam dip angle less than 12°, coal seam burial depth less than 300m (shallow burial), bedrock Protodyakonov hardness coefficient less than 15 and weak cementation (soft rock), and bedrock thickness less than 200m (thin bedrock). These conditions must be met for this method to be applied correctly.

[0056] Step (2) The main contents of the basic physical and mechanical parameter testing of coal and rock samples include: obtaining coal and rock samples at the location of the proposed mining face in the applied mine by drilling or cutting, etc. The volume of a single coal and rock sample must be at least larger than a cylinder (standard sample for compressive strength) cut out of 50mm (diameter) × 100mm (height). The preparation of standard specimens and the testing process of the physical and mechanical properties test of coal and rock are strictly carried out in accordance with the "Standard for Methods for Determination of Physical and Mechanical Properties of Coal and Rock" and the "Test Procedure for Physical and Mechanical Properties of Rock" to obtain the basic physical and mechanical properties of rock such as tensile strength and compressive strength.

[0057] Step (3) Simulation and theoretical analysis to determine the conditions for timely bedrock fracture mainly includes: Based on the coal seam occurrence conditions of the applied working face and the basic physical and mechanical parameters of the coal and rock samples measured in step (2) of this method, a theoretical mechanical model is established. The bedrock is regarded as a composite beam with elastic connection in the middle. The load on the upper part of the beam bearing the loose rock layer is equivalent to a uniformly distributed load, and the lower coal seam is simplified as a Winkler elastic body. Dip and strike models are established respectively, and calculation and analysis are performed by changing the face length, advance step distance and other conditions. The threshold of the working face mining parameters is obtained by taking the bedrock reaching the ultimate bending moment as the criterion for fracture.

[0058] Step (4) Design of working face mining parameters mainly includes: based on the threshold of working face mining parameters obtained in step (3), combined with the mine's production capacity, equipment, transportation and other production conditions, design the working face length, mining height and advance step distance to ensure that the overlying rock of the working face can sink in time.

[0059] Step (5) The main contents of optimizing the support parameters of the mining roadway include: During the mining process, the support elements that enhance the strength and integrity of the roof in the mining roadway are removed to prevent the roof from being suspended in the roadway and affecting the overall subsidence of the rock strata.

[0060] This method has clear steps and is simple to operate, reducing unnecessary water control measures, significantly lowering the cost of water control in mines, and providing a reference for water control work in similar types of mines.

[0061] To make the objectives and advantages of this invention clearer, it was implemented in a mine in Xinjiang Uygur Autonomous Region under shallow-buried, thin-bedded, soft rock conditions. The main steps are as follows:

[0062] Step 1: Through investigation of the mine's dip angle, burial depth, bedrock thickness, and bedrock hardness, the coal seam dip angle of the working face is 6°, the average burial depth is 170m, the bedrock thickness is 50-117m, the Protodyakonov hardness coefficient of the bedrock is less than 15, and it has weak cementation (soft rock), which meets the applicable conditions of this method.

[0063] Step 2: Drilling samples were taken from the roof of the coal roadway in the transport section of the working face. The basic physical and mechanical parameters of the coal and rock mass of the working face were obtained according to the test and measurement method in step (2) of this patent specification. See Table 1 for the basic physical and mechanical properties of the rock of a certain mine.

[0064] Table 1

[0065]

[0066] Step 3: Established as follows Figure 3The physical and mechanical model was used, and the face length parameters 80m, 120m, 160m, 200m (actual working face conditions), 240m and the advance step parameters 4.8m, 6.4m, 8m, 9.6m were substituted into the solution to obtain the threshold of mining parameters when the roof is at its ultimate breaking point: the face length is greater than 160m and the daily advance speed is greater than 8m.

[0067] Step 4: The length of the working face and the advance speed are determined based on meeting the production capacity as the main criterion for this mine. In order to meet the mine's production capacity (330 days, 10 million tons / year), the daily output of the working face must reach more than 30,300 tons. The relationship between output, face length, and daily cycle number is shown in equation (1).

[0068] Q=(h c +k f ×h f )×L×n×B×ρ m (1)

[0069] In the formula, Q—daily output, t; h c — Coal mining height, m; h f — Coal mining height, m; k f —Coal discharge coefficient; n—Number of cycles, m; L—Face length, m; B—Cycle advance, m; ρ m — Coal density, t / m3.

[0070] Coal mining height h c The depth is 3.8m, and the coal mining height is h. f The length is 11.6m, and the coal discharge coefficient is k. f Taking 0.85, the cycle advance B is 0.8m, and the coal density is 1.4t / m³. 3 Substituting the above parameters into equation (1), we obtain the relationship between the number of cycles n and the surface length L as follows: Figure 4 As shown. Based on previous mining parameters, the following parameters were determined: a face length of 240m and a cycle count of 10.

[0071] Step 5: Combining the existing support technology of the mine's mining roadway, the process flow for removing the support components of the mining roadway is designed as follows: (1) After the working face has been mined past the end and the end frame has been moved, two rows of single props are erected 0.5m away from the center of the rear scraper to temporarily support the roof of the end. The center of the prop is 1000mm away from the roadway wall, the prop spacing is 3000mm, the row spacing is 500mm, and the number of single rows is determined according to the removal speed of the support components; (2) Then, the anchor bolts, anchor cables, steel strips and other support components on the top are removed respectively; (3) Finally, the single props are recovered. The specific process is as follows: Figure 5 , Figure 6 , Figure 7 , Figure 8 , Figure 9 As shown.

[0072] This method has clear steps and is easy to operate, reducing unnecessary water control measures, greatly reducing the cost of water control in mines, and providing a reference for water control work in similar types of mines.

[0073] Example 2

[0074] The present invention also provides a two-zone water control design system for shallow buried thin foundation soft rock, including: a condition acquisition module, a testing module, a discrimination module, a parameter acquisition module and an optimization module;

[0075] The condition acquisition module is used to acquire coal seam occurrence conditions and overlying strata conditions;

[0076] The testing module is used to test the basic physical and mechanical parameters of coal and rock samples;

[0077] The discrimination module is used to perform simulation and theoretical analysis based on the coal seam occurrence conditions, the overburden conditions and the basic physical and mechanical parameters of the coal and rock samples to determine the conditions for timely bedrock fracture.

[0078] The parameter acquisition module is used to obtain the working face mining parameters based on the timely fracture conditions of the bedrock;

[0079] The optimization module is used to optimize the support parameters of the mining roadway based on the mining parameters of the working face, thereby completing the overall structural water inrush prevention of the rock strata.

[0080] In this embodiment, the main contents of the investigation of coal seam occurrence conditions and overlying strata conditions include: investigating the dip angle, burial depth, bedrock thickness, and bedrock hardness of the mine. This method is aimed at the design of working faces under special conditions. The proposed working face must meet the following conditions: coal seam dip angle less than 12°, coal seam burial depth less than 300m (shallow burial), bedrock Protodyakonov hardness coefficient less than 15 and weak cementation (soft rock), and bedrock thickness less than 200m (thin bedrock). These conditions must be met for this method to be correctly applied.

[0081] In this embodiment, the main contents of the basic physical and mechanical parameter testing of coal and rock samples include: obtaining coal and rock samples at the proposed mining face location in the applied mine using drilling or cutting methods, ensuring that the volume of a single coal and rock sample is at least larger than a cylinder (standard specimen for compressive strength) cut from it (50mm (diameter) × 100mm (height). The preparation of standard specimens and the testing process for the physical and mechanical properties of coal and rock are strictly carried out in accordance with the "Standard for Methods for Determining Physical and Mechanical Properties of Coal and Rock" and the "Test Procedure for Physical and Mechanical Properties of Rock," obtaining the basic physical and mechanical properties of the rock such as tensile strength and compressive strength.

[0082] In this embodiment, the simulation and theoretical analysis to determine the conditions for timely bedrock fracture mainly include: establishing a theoretical mechanical model based on the coal seam occurrence conditions of the applied working face and the measured basic physical and mechanical parameters of the coal and rock samples. The bedrock is considered as a composite beam with an elastic connection in the middle, the load on the upper part of the beam from the loose rock strata is equivalent to a uniformly distributed load, and the lower coal seam is simplified as a Winkler elastic body. Dip and strike models are established separately, and calculations and analyses are performed by changing conditions such as face length, mining height, and advance step distance. The threshold values ​​for the working face mining parameters are obtained by using the bedrock reaching its ultimate bending moment as the criterion for fracture.

[0083] In this embodiment, the main contents of designing the working face mining parameters include: based on the threshold values ​​of the obtained working face mining parameters, combined with the mine's production capacity, equipment, transportation and other production conditions, designing the working face length and advancing step distance to ensure that the overburden of the working face can sink in a timely manner.

[0084] In this embodiment, the main contents of the optimization of the support parameters of the mining roadway include: during the mining process, the support elements that enhance the strength and integrity of the roof in the mining roadway are removed to prevent the roof from being suspended in the roadway and affecting the overall subsidence of the rock strata.

[0085] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made to the technical solutions of the present invention by those skilled in the art without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A shallow-buried thin-base soft rock two-zone water control design method, characterized in that, Includes the following steps: Obtain coal seam occurrence conditions and overlying strata conditions; Test the basic physical and mechanical parameters of coal and rock samples; Based on the coal seam occurrence conditions, the overburden conditions, and the basic physical and mechanical parameters of the coal and rock samples, simulation and theoretical analysis are conducted to determine the conditions for timely bedrock fracture. Based on the aforementioned bedrock fracture conditions, the working face mining parameters are obtained; Based on the mining parameters of the working face, the support parameters of the mining roadway are optimized to complete the overall structural water inrush prevention of the rock strata. The coal seam occurrence conditions and overlying strata conditions include: the dip angle of the mine, the burial depth, the bedrock thickness, and the bedrock hardness; Among them, the coal seam dip angle is less than 12°, the coal seam burial depth is less than 300m, the bedrock hardness coefficient is less than 15 and has weak cementation, and the bedrock thickness is less than 200m; Based on the coal seam occurrence conditions, the overlying strata conditions, and the basic physical and mechanical parameters of the coal and rock samples, methods for determining the conditions for timely bedrock fracture through simulation and theoretical analysis include: A theoretical mechanical model is established based on the coal seam occurrence conditions, the overburden conditions, and the basic physical and mechanical parameters of the coal and rock samples. In the theoretical mechanics model, the bedrock is regarded as a composite beam with an elastic connection in the middle. The load on the upper part of the composite beam and the loose rock layer is equivalent to a uniformly distributed load. The coal seam below the composite beam is simplified as a Winkler elastic body. Dip model and strike model are established respectively. Based on the aforementioned tendency model and the aforementioned direction model, calculations and analyses are performed by changing the surface length and the advancing step distance to determine the conditions for timely bedrock fracture. Among these, the bedrock reaching the ultimate bending moment is used as the criterion for fracture.

2. The method for shallow-buried thin soft rock two-zone water control design according to claim 1, characterized in that, Methods for testing the basic physical and mechanical parameters of coal and rock samples include: Obtain a coal and rock sample of a predetermined volume; The coal and rock samples were processed to obtain the tensile strength, compressive strength, shear strength, and hardness of the rock.

3. The water control design method for shallow-buried thin-foundation soft rock with two zones according to claim 1, characterized in that, During the mining process at the working face, the support elements that enhance the strength and integrity of the roof in the mining roadway are removed.

4. A shallow-buried thin foundation soft rock two-zone water control design system, characterized in that, include: The module includes a condition acquisition module, a testing module, a discrimination module, a parameter acquisition module, and an optimization module. The condition acquisition module is used to acquire coal seam occurrence conditions and overlying strata conditions; The testing module is used to test the basic physical and mechanical parameters of coal and rock samples; The discrimination module is used to perform simulation and theoretical analysis based on the coal seam occurrence conditions, the overburden conditions and the basic physical and mechanical parameters of the coal and rock samples to determine the conditions for timely bedrock fracture. The parameter acquisition module is used to obtain the working face mining parameters based on the timely fracture conditions of the bedrock; The optimization module is used to optimize the support parameters of the mining roadway based on the mining parameters of the working face, so as to complete the overall structural water inrush prevention of the rock strata. The coal seam occurrence conditions and overlying strata conditions include: the dip angle of the mine, the burial depth, the bedrock thickness, and the bedrock hardness; Among them, the coal seam dip angle is less than 12°, the coal seam burial depth is less than 300m, the bedrock hardness coefficient is less than 15 and has weak cementation, and the bedrock thickness is less than 200m; Based on the coal seam occurrence conditions, the overlying strata conditions, and the basic physical and mechanical parameters of the coal and rock samples, the process of determining the conditions for timely bedrock fracture through simulation and theoretical analysis includes: A theoretical mechanical model is established based on the coal seam occurrence conditions, the overburden conditions, and the basic physical and mechanical parameters of the coal and rock samples. In the theoretical mechanics model, the bedrock is regarded as a composite beam with an elastic connection in the middle. The load on the upper part of the composite beam and the loose rock layer is equivalent to a uniformly distributed load. The coal seam below the composite beam is simplified as a Winkler elastic body. Dip model and strike model are established respectively. Based on the aforementioned tendency model and the aforementioned direction model, calculations and analyses are performed by changing the surface length and the advancing step distance to determine the conditions for timely bedrock fracture. Among these, the bedrock reaching the ultimate bending moment is used as the criterion for fracture.

5. The shallow-buried thin foundation soft rock two-zone water control design system according to claim 4, characterized in that, The process of testing the basic physical and mechanical parameters of coal and rock samples includes: Obtain a coal and rock sample of a predetermined volume; The coal and rock samples were processed to obtain the tensile strength, compressive strength, shear strength, and hardness of the rock.

6. The shallow-buried, thin-foundation soft rock two-zone water control design system according to claim 4, characterized in that, During the mining process at the working face, the support elements that enhance the strength and integrity of the roof in the mining roadway are removed.

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