A method for disaster management in goaf areas based on supplementary exploration

Abstract

The invention relates to a goaf disaster management method based on supplementary exploration. First, supplementary exploration is carried out to determine the inclination range of the original mining working face and the section coal pillar in the goaf. At the same time, based on the position of the upper basic roof of the collapse zone explored by supplementary exploration drilling holes at different positions, the actual subsidence value of the basic roof along the width direction after the working face is mined is fitted; then the theoretical subsidence value of the basic roof is calculated, and based on the comparison results of the two, the concepts of the goaf stabilization zone and the goaf management zone are creatively proposed, that is, the goaf does not need to be fully processed but only partially processed; finally, based on the level of ground stability requirements, two grouting drilling arrangement schemes are given, which greatly improves the drilling construction position accuracy, reduces the drilling construction volume and grouting filling volume, and saves cost and time.

Description

Technical Field

[0001] The invention relates to the field of geological exploration and goaf disaster management, and in particular to a goaf disaster management method based on supplementary exploration. Background Art

[0002] Coal mine goaf is one of the common mine disasters. Due to its instability, the ground above it cannot be used. The most common way to deal with goaf disasters is to inject filling slurry into the goaf through grouting drilling. However, in the prior art, grouting drilling is often arranged in the entire goaf based on a fixed spacing, without considering the state of collapsed rocks in the goaf, resulting in a large amount of grouting drilling construction, a large amount of engineering work for the entire disaster treatment, low efficiency and high cost. This situation is more serious when the original working face layout plan and mining parameters of the goaf are unclear. In addition, coal gangue will be produced during the mining process of coal mines. The coal gangue is piled up on the ground into mountains, and the fly ash produced by coal-fired power generation in thermal power plants is also stored in large quantities on the surface. These two types of waste deposits will pollute groundwater, and their dust will also pollute the air. It is imperative to treat these two types of solid wastes. Summary of the invention

[0003] In view of the deficiencies in the above-mentioned prior art, the present invention proposes a method for goaf disaster management based on supplementary exploration, which comprises the following steps:

[0004] S1, based on the existing geological data, preliminarily determine the approximate direction of the coal layer to which the goaf belongs, so as to determine the approximate length direction of the original mining face in the original mining area;

[0005] S2, two supplementary exploration lines are arranged at intervals along the approximate inclination of the goaf, and supplementary exploration boreholes are constructed at intervals on the supplementary exploration lines. Conventional drilling methods are used to drill from the ground to a certain height above the water-conducting fracture zone, and then the core drilling process is used. The final hole of the supplementary exploration borehole located on the original mining face is constructed to the collapse zone, and the final hole of the supplementary exploration borehole located on the section coal pillar passes through the section coal pillar to a certain depth; in order to supplement the exploration of the inclination range of the original mining face in the goaf and the section coal pillar between them, and determine the position of the basic top of the collapse zone;

[0006] Preferably, the supplementary exploration borehole is a vertical borehole, and the rock layer section of the first supplementary exploration borehole constructed adopts full coring drilling to roughly determine the strata of the water-conducting fracture zone and the collapse zone, providing a basis for roughly determining the coring section of the subsequent supplementary exploration boreholes.

[0007] Preferably, firstly, a number of supplementary exploration boreholes are constructed along the supplementary exploration line at a certain interval, and then a number of supplementary exploration boreholes are constructed again on both sides of the roughly determined water-conducting fracture zone or collapse zone inclination.

[0008] Preferably, the locations of the water-conducting fracture zone and the collapse zone are determined based on the drilling resistance, the drill sticking and holding conditions, the flushing fluid leakage conditions or the coring results.

[0009] Preferably, the points on the two supplementary exploration lines that determine the boundary between the section coal pillar and the original mining face are connected into a line. The extension direction of the line is the advancement direction of the original mining face and is also the inclination boundary line between the section coal pillar and the original mining face.

[0010] Preferably, based on the position of the top boundary of the water-conducting fracture zone or the collapse zone determined by each supplementary exploration drill on the supplementary exploration line, a saddle-shaped top boundary of the water-conducting fracture zone or the collapse zone along the supplementary exploration line is approximately fitted, and points with the same height and approximately in the same direction are connected to form a line. The extension direction of the line is the advancement direction of the original mining working face. Then, the saddle-shaped top boundary of the water-conducting fracture zone or the collapse zone along the width direction / inclination of the original mining working face is determined. Combined with the relationship between the saddle shape of the top boundary of the water-conducting fracture zone or the collapse zone and the width range of the original mining working face, the inclination range of the original mining working face and the section coal pillar is roughly determined.

[0011] S3, based on the supplementary exploration results of step S2, a basic top position curve along the width direction / inclination of the original mining face is fitted, wherein the basic top elevations of the section coal pillar and the upper part of the original mining face are H 1 , H 2 , let C 1 =H 1 -H 2 The actual subsidence value of the upper basic roof of the original mining face after mining can be obtained;

[0012] S4, determine the theoretical sinking amount of the basic top as C 2 ;

[0013] It can be determined by physical simulation, numerical simulation or theoretical calculation. As a preferred method, the present invention proposes a creative determination method, specifically: core rock blocks from supplementary exploration boreholes located on the coal pillars of the section are made into standard samples, and mechanical parameter tests are performed to determine the uniaxial compressive strength of each rock layer in the collapse zone and the original thickness of the rock layer in the collapse zone;

[0014] The stress-deformation relationship formula of the broken rock mass in the collapse zone proposed by Salamon is transformed into the deformation-stress relationship formula

[0015]

[0016] in

[0017]

[0018]

[0019] Then the theoretical compression of the broken rock mass in the collapse zone, that is, the theoretical subsidence of its upper basic top, is C 2 =εH k ;

[0020] Where: σ is the stress of the broken rock mass in the collapse zone, which is the gravity of the overlying strata of the broken rock mass in the collapse zone. The greater the burial depth, the greater the stress. It can be determined according to the thickness and density of each layer of the overlying strata. The density and thickness can be determined according to the coring conditions of the supplementary exploration borehole in step S2; ε is the strain of the broken rock mass in the collapse zone. Here, the strain at the vertical center of the broken rock mass in the collapse zone is obtained; ε m E is the maximum strain of the broken rock mass in the collapse zone; 0 B is the initial shear modulus of the broken rock mass in the collapse zone; 0 is the initial expansion coefficient of the broken rock mass in the collapse zone, which can be determined based on the measured parameters under similar working conditions in the mine where the goaf is located or other mines; σ 0 is the uniaxial compressive strength of the rock mass in the collapse zone, which can be approximately taken as the average value of each rock layer in the collapse zone; H k is the initial thickness of the broken rock mass in the collapse zone, which can be determined by the product of the original thickness of the rock layer in the collapse zone and the initial expansion coefficient of the broken rock mass in the collapse zone;

[0021] S5, determine the actual subsidence value C of the basic roof at different positions along the width direction of the original mining working face 1 , if C 1 ≥90%·C 2 , it is considered that the broken rock mass in the collapse zone here is relatively stable, and such an area in the goaf is defined as the goaf stable area, and the part on both sides of the goaf stable area to the section coal pillar is the goaf governance area;

[0022] S6, if the ground stability requirement is high, then execute this step, otherwise execute step S7; construct a grouting borehole in the middle of the coal pillar inclination of the section, and construct the final borehole to a certain height above the water-conducting fracture zone, and then construct a branch grouting borehole in the side goaf treatment area, and the final borehole of the branch grouting borehole is constructed to the collapse zone and is located in the middle of the goaf treatment area in terms of inclination;

[0023] Preferably, for the goaf control area located at the boundary of the goaf, vertical grouting boreholes are constructed, and the final hole of the grouting borehole is constructed to the collapse zone and is located in the middle of the goaf control area in terms of inclination.

[0024] Preferably, the bottom of the supplementary exploration borehole located on the coal pillar of the section is sealed until a certain height above the water-conducting fracture zone, and then a branch grouting borehole is constructed toward the side goaf management area, and the final hole of the branch grouting borehole is constructed to the collapse zone, and the final hole is inclined to be located in the middle of the goaf management area; the supplementary exploration borehole located above the goaf management area is also used as a grouting borehole for grouting.

[0025] S7, if the demand for ground stability is relatively low, a vertical grouting borehole is constructed in the goaf treatment area on the upper side of each original mining face, and the final hole is constructed to the collapse zone and is located in the middle of the goaf treatment area in terms of tendency;

[0026] S8, using fly ash and / or coal gangue powder obtained by crushing coal gangue, adding it into water to prepare slurry, injecting it into the goaf treatment area 10 through the grouting drilling hole 8 to treat the goaf disaster.

[0027] Beneficial effect: The present invention relates to a method for goaf disaster management based on supplementary exploration. First, supplementary exploration is carried out to determine the inclination range of the original mining face and the section coal pillar in the goaf. At the same time, based on the position of the upper basic roof of the collapse zone explored by supplementary exploration drilling at different positions, the actual subsidence value of the basic roof along the width direction after the mining of the working face is fitted (a method for determining the range of the original mining face and the section coal pillar and a method for determining the actual subsidence value of the basic roof are creatively provided); then, the Salamon variation model is used to calculate the theoretical subsidence value of the basic roof, and based on the comparison results of the two, the concepts of the goaf stabilization zone and the goaf management zone are creatively proposed, that is, the goaf does not need to be treated in the entire area, but only partially treated; finally, based on the level of ground stability requirements, two grouting drilling arrangement schemes are provided, which greatly improves the drilling construction position accuracy, reduces the drilling construction volume and the grouting filling volume, and saves cost and time; in addition, fly ash and coal gangue powder obtained by crushing coal gangue are used as grouting materials, which not only realizes the disaster management of the goaf of coal mines, but also consumes these two solid wastes. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the arrangement of the supplementary detection lines of the present invention.

[0029] Figure 2 It is a cross-sectional schematic diagram of the supplementary exploration and goaf disaster management of the present invention (with relatively high treatment requirements);

[0030] Figure 3 It is a cross-sectional schematic diagram of the supplementary exploration and goaf disaster management of the present invention (the treatment requirements are relatively low);

[0031] Figure 2-3 The leftmost working face only shows some supplementary detection boreholes, and the other working faces only show grouting boreholes.

[0032] In the figure: goaf 1, original mining working face 2, section coal pillar 3, supplementary exploration line 4, supplementary exploration borehole 5, water-conducting fracture zone 6, collapse zone 7, grouting borehole 8, goaf stabilization zone 9, goaf management zone 10. DETAILED DESCRIPTION

[0033] The technical solution of the present invention is described in more detail below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0034] like Figure 1-3 As shown, a method for goaf disaster management based on supplementary exploration is applied to the situation where the original mining face 2 and the layout scheme of the section coal pillar 3 of the goaf 1 and the related mining parameters are missing, including the following steps:

[0035] S1, based on the existing geological data, preliminarily determine the approximate direction of the coal layer to which the goaf 1 belongs, so as to determine the approximate advancement direction of the original mining face 2 in the original mining area, that is, the length direction of the original mining face 2;

[0036] When the coal mining area is arranged, the length direction of the working face in the mining area is basically the same as the direction of the coal mine layer. By determining the approximate direction of the coal mine layer to which the goaf belongs, the advancement direction of the original mining working face 2 is roughly determined; based on this, a supplementary exploration line 4 that is closer to the inclination of the coal mine layer can be arranged, thereby reducing the number of supplementary exploration drill holes 5, and improving the efficiency and accuracy of exploring the inclination range (width) of the original mining working face 2 and the section coal pillar 3.

[0037] S2, two supplementary exploration lines 4 are arranged at intervals along the approximate inclination of the goaf, and supplementary exploration boreholes 5 are constructed at intervals on the supplementary exploration lines 4. Conventional drilling is adopted to start drilling from the ground to a certain height above the water-conducting fracture zone 6, and then the core drilling process is adopted. The supplementary exploration boreholes 5 located on the original mining face 2 are finally constructed to the collapse zone 7, and the supplementary exploration boreholes 5 located on the section coal pillar 3 are finally constructed to a certain depth through the section coal pillar; thereby, the original mining face 2 in the goaf and the inclination range (width) of the section coal pillar 3 between the original mining face 2 are supplementarily explored, and the position of the upper basic top of the collapse zone is determined;

[0038] Preferably, the supplementary exploration borehole 5 is a vertical borehole, and the rock layer section of the first supplementary exploration borehole 5 constructed is drilled using full coring to roughly determine the water-conducting fracture zone and collapse zone layer position (elevation / depth position) of the goaf, providing a basis for roughly determining the coring section of the subsequent supplementary exploration borehole 5.

[0039] Preferably, first, a number of supplementary exploration boreholes 5 are constructed along the supplementary exploration line 4 at a certain interval, and then a number of supplementary exploration boreholes 5 are constructed again on both sides of the roughly determined water-conducting fracture zone 6 or collapse zone 7. In this way, the inclination range (width) of the original mining working face 2 and the section coal pillar 3 in the goaf and the position of the basic top of the collapse zone can be more accurately supplemented and explored on the basis of reducing the amount of engineering.

[0040] Preferably, the positions of the water-conducting fracture zone 6 and the collapse zone 7 are determined based on drilling characteristics (drilling resistance, drill sticking and holding conditions, flushing fluid leakage, etc.) or coring results.

[0041] Preferably, the points on the two supplementary exploration lines 4 that determine the boundary between the sectional coal pillar 3 and the original coal mining face 2 are connected into a line, and the extension direction of this line is the advancing direction of the original coal mining face 2 and also the dip boundary line between the sectional coal pillar 3 and the original coal mining face 2.

[0042] Preferably, according to the top boundary positions of the water-conducting fissure zone 6 or caving zone 7 determined by each supplementary exploration borehole 5 on the supplementary exploration line 4, an approximately saddle-shaped top boundary line of the water-conducting fissure zone or caving zone along the supplementary exploration line 4 is fitted. Points with the same height and approximately in the same strike are connected into a line, and the extension direction of this line is the advancing direction of the original coal mining face 2. Then, an approximately saddle-shaped top boundary line of the water-conducting fissure zone or caving zone along the width direction (perpendicular to the length direction of the original coal mining face 2) of the original coal mining face 2 is determined. Combining the relationship between the saddle shape of the top boundary line of the water-conducting fissure zone or caving zone and the width range of the original coal mining face 2, the dip ranges of the original coal mining face 2 and the sectional coal pillar 3 are approximately determined.

[0043] For coal seams that have been mined, when a long time has passed and the mining area layout plan is lost, the original mining parameters cannot be determined, and the ranges of the sectional coal pillar 3 and the original coal mining face 2 are not clear. Then, the grouting boreholes for goaf disaster control cannot be reasonably arranged, and if exploration is required, the site selection of exploration boreholes is also a problem. For this, the present invention provides two methods for determining the dip ranges of the original coal mining face 2 and the sectional coal pillar 3.

[0044] S3, if the positions of the basic roofs above the caving zones in the same strike in the goaf are the same, then based on the supplementary exploration results of step S2 (the dip ranges of the original coal mining face 2 and the sectional coal pillar 3, and the positions of the basic roofs at each supplementary exploration borehole 5), a curve of the basic roof position along the width direction (perpendicular to the advancing direction of the original coal mining face) of the original coal mining face 2, that is, the dip, is fitted. The basic roof elevations above the sectional coal pillar 3 and the original coal mining face 2 are H 1 、H 2 , respectively. The basic roof elevation above the sectional coal pillar can be approximately used as the original elevation of the basic roof. Let C 1 = H 1 - H 2 to obtain the actual subsidence value of the basic roof above the original coal mining face 2 after mining (width direction / dip) of the working face;

[0045] S4, the cored rock blocks of the supplementary exploration boreholes 5 located on the sectional coal pillar 3 are made into standard specimens, and mechanical parameter tests are carried out to determine the uniaxial compressive strength of each rock layer in the caving zone and the original thickness of the rock layers in the caving zone;

[0046] The formula for the stress and deformation relationship of the broken rock mass in the caving zone proposed by Salamon

[0047]

[0048] Transformed into deformation and force relationship formula

[0049]

[0050] in

[0051]

[0052]

[0053] Based on this, the theoretical compression of the broken rock mass in the collapse zone, that is, the theoretical subsidence of its upper basic top, is determined as C 2 =εH k , the sum of the strains of the collapse zone in the vertical direction is the cumulative compression of the collapse zone. To simplify the calculation, the theoretical compression of the broken rock mass in the collapse zone is approximately obtained by multiplying the strain at the vertical center of the collapse zone by the height of the collapse zone.

[0054] Where: σ is the stress of the broken rock mass in the collapse zone, which is the gravity of the overlying strata of the broken rock mass in the collapse zone. The greater the burial depth, the greater the stress. It can be determined according to the thickness and density of each layer of the overlying strata. The density and thickness can be determined according to the coring conditions of the supplementary exploration borehole in step S2; ε is the strain of the broken rock mass in the collapse zone. Here, the strain at the vertical center of the broken rock mass in the collapse zone is obtained; ε m E is the maximum strain of the broken rock mass in the collapse zone; 0 B is the initial shear modulus of the broken rock mass in the collapse zone; 0 is the initial expansion coefficient of the broken rock mass in the collapse zone, which can be determined based on the measured parameters under similar working conditions in the mine where the goaf is located or other mines; σ 0 is the uniaxial compressive strength of the rock mass in the collapse zone, which can be approximately taken as the average value of each rock layer in the collapse zone; H k is the initial thickness of the broken rock mass in the collapse zone, which can be determined by the product of the original thickness of the rock layer in the collapse zone and the initial expansion coefficient of the broken rock mass in the collapse zone;

[0055] S5, determine the actual subsidence value C of the basic roof at different positions along the width direction of the original mining working face 2 (perpendicular to the advancement direction of the original mining working face) 1 , compare C 1 With C 2 , if C 1 ≥90%·C 2, it is considered that the broken rock mass in the goaf collapse zone here has been relatively stable, and such an area in the goaf is defined as the goaf stable area, and the part of the goaf stable area on both sides to the section coal pillar is the goaf management area 10. Since the subsequent residual compressible amount in the goaf stable area 9 is very small, the residual compressible amount of this part will be even smaller when transferred to the surface (considering the influence of the sinking coefficient), it is considered that the goaf stable area 9 has reached relative stability and does not need grouting filling. It is only necessary to perform grouting filling on the goaf management area 10 that has not reached relative stability;

[0056] S6, if the ground stability requirement is high, execute this step, otherwise execute step S7;

[0057] like Figure 2 As shown, a grouting borehole 8 is constructed in the middle of the coal pillar 3 in the section, and the final hole of the grouting borehole 8 is constructed to a certain height above the water-conducting fracture zone 6, and then a branch grouting borehole is constructed toward the goaf treatment zone 10 on the side, and the final hole of the branch grouting borehole is constructed to the collapse zone, and the final hole is located in the middle of the goaf treatment zone 10 in terms of tendency;

[0058] Preferably, for the goaf treatment area 10 located at the boundary of the goaf, a vertical grouting borehole 8 is constructed, and the final hole of the grouting borehole is constructed to the collapse zone and is located in the middle of the goaf treatment area 10 in terms of tendency.

[0059] Preferably, the bottom of the supplementary exploration borehole 5 located on the coal pillar of the section is sealed until a certain height above the water-conducting fracture zone, and then a branch grouting borehole is constructed toward the side goaf management area 10, and the final hole of the branch grouting borehole is constructed to the collapse zone, and the final hole is inclined to be located in the middle of the goaf management area 10; the supplementary exploration borehole 5 located above the goaf management area 10 is also used as a grouting borehole for grouting.

[0060] S7, such as Figure 3 As shown, if the demand for ground stability is relatively low, a vertical grouting borehole 8 is constructed in the goaf treatment area 10 on the inclined upper side of each original mining working face 2, and the final grouting borehole is constructed to the collapse zone and is located in the middle of the goaf treatment area 10 in terms of tendency;

[0061] S8, using fly ash and / or coal gangue powder crushed from coal gangue, adding it to water to prepare slurry, injecting it into goaf treatment area 10 through grouting borehole 8, to treat goaf disasters. The creative choice of grouting filling in the upper goaf treatment area is because the solid particles in the injected slurry can be intercepted by the goaf stabilization area with very small porosity in the upper goaf treatment area, and water is filtered through the goaf stabilization area and seeps into the lower goaf treatment area.

[0062] Although the present invention has been described in detail above by general description and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements can be made on the basis of the present invention. Therefore, these modifications or improvements made on the basis of not departing from the spirit of the present invention all belong to the scope of protection claimed by the present invention.

Claims

1. A method for disaster management of goaf areas based on supplementary exploration, It is characterized in that The steps include: S1, based on the existing geological data, preliminarily determine the approximate direction of the coal layer to which the goaf belongs, so as to determine the approximate length direction of the original mining face in the original mining area; S2, two supplementary exploration lines are arranged at intervals along the approximate inclination of the goaf, and supplementary exploration boreholes are constructed at intervals on the supplementary exploration lines. Conventional drilling methods are used to drill from the ground to a certain height above the water-conducting fracture zone, and then the core drilling process is used. The final hole of the supplementary exploration borehole located on the original mining face is constructed to the collapse zone, and the final hole of the supplementary exploration borehole located on the section coal pillar passes through the section coal pillar to a certain depth; in order to supplement the exploration of the inclination range of the original mining face in the goaf and the section coal pillar between them, and determine the position of the basic top of the collapse zone; S3, based on the supplementary exploration results of step S2, a basic top position curve along the width direction of the original mining face is fitted, wherein the basic top elevations of the section coal pillar and the upper part of the original mining face are H 1 , H 2 , let C 1 =H 1 -H 2 The measured subsidence value of the upper basic roof of the original mining face after mining can be obtained; S4, cored rock blocks from supplementary exploration boreholes on the coal pillars of the section are made into standard samples, and mechanical parameter tests are performed to determine the uniaxial compressive strength of each rock layer in the collapse zone and the original thickness of the rock layer in the collapse zone; The stress-deformation relationship formula of the broken rock mass in the collapse zone proposed by Salamon is transformed into the deformation-stress relationship formula in Then the theoretical compression of the broken rock mass in the collapse zone, that is, the theoretical subsidence of its upper basic top, is C 2 =εH k ; Where: σ is the stress on the broken rock mass in the caving zone; ε is the strain of the broken rock mass in the caving zone, taking the strain at the center in the vertical direction of the broken rock mass in the caving zone; ε m is the maximum strain of the broken rock mass in the caving zone; E 0 is the initial shear modulus of the broken rock mass in the caving zone; B 0 is the initial bulking coefficient of the broken rock mass in the caving zone; σ 0 is the uniaxial compressive strength of the rock mass in the caving zone, taking the average value; H k is the initial thickness of the broken rock mass in the caving zone; S5, determine the actual subsidence value C of the basic roof at different positions along the width direction of the original mining working face 1 , if C 1 ≥90%·C 2 , it is considered that the broken rock mass in the collapse zone here is relatively stable, and such an area in the goaf is defined as the goaf stable area, and the part on both sides of the goaf stable area to the section coal pillar is the goaf governance area; S6, if the ground stability requirement is high, then execute this step, otherwise execute step S7; construct a grouting borehole in the middle of the coal pillar inclination of the section, and construct the final borehole to a certain height above the water-conducting fracture zone, and then construct a branch grouting borehole in the side goaf treatment area, and the final borehole of the branch grouting borehole is constructed to the collapse zone and is located in the middle of the goaf treatment area in terms of inclination; S7, if the demand for ground stability is relatively low, a vertical grouting borehole is constructed in the goaf treatment area on the upper side of each original mining face, and the final hole is constructed to the collapse zone and is located in the middle of the goaf treatment area in terms of tendency; S8, using fly ash and / or coal gangue powder obtained by crushing coal gangue, adding it into water to prepare slurry, injecting it into the goaf treatment area through grouting drilling to treat the goaf disaster.

2. The method for managing goaf disaster according to claim 1, It is characterized in that In step S2, the supplementary exploration borehole is a vertical borehole, and the rock layer section of the first supplementary exploration borehole constructed is fully cored to roughly determine the water-conducting fracture zone and the collapse zone layer, providing a basis for roughly determining the coring section of subsequent supplementary exploration boreholes.

3. The method for managing goaf disaster according to claim 1, It is characterized in that In step S2, the points on the two supplementary exploration lines that determine the boundary between the section coal pillar and the original mining face are connected into a line. The extension direction of the line is the advancement direction of the original mining face and is also the inclination boundary line between the section coal pillar and the original mining face.

4. The method for managing goaf disaster according to claim 1, It is characterized in that In step S6, vertical grouting boreholes are constructed in the goaf treatment area located at the boundary of the goaf, and the final hole of the grouting borehole is constructed to the collapse zone and is located in the middle of the goaf treatment area in terms of tendency.

5. The method for managing goaf disaster according to claim 1, It is characterized in that In step S6, the bottom of the supplementary exploration borehole located on the coal pillar of the section is sealed until a certain height above the water-conducting fracture zone, and then a branch grouting borehole is constructed toward the side goaf management area. The final hole of the branch grouting borehole is constructed to the collapse zone, and the final hole is inclined to be located in the middle of the goaf management area; the supplementary exploration borehole located above the goaf management area is also used as a grouting borehole for grouting.

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