Method for preventing and controlling rock burst of mining area roadway group through distributed kerf fracturing in rock stratum roadway

Abstract

The invention relates to a method for preventing and controlling rock burst of a mining area roadway group through distributed kerf fracturing in a rock stratum roadway. The method comprises the following steps that a pressure relief process roadway is tunneled in a rock stratum above a coal seam; a drill site is arranged on the pressure relief process roadway, pressure relief holes are drilled in at least one side of the drill site, the pressure relief holes of the same drill site cover the roadway group in the width direction of the roadway group, a plurality of pressure relief seams are cut in the pressure relief holes, and hydraulic fracturing is carried out at the pressure relief seams to form fractures; and a plurality of drill sites are arranged on the pressure relief process roadway until the laneway group is covered by the kerf fracturing area. According to the method for preventing and controlling rock burst of the mining area roadway group through distributed kerf fracturing in the rock stratum roadway, dense kerf fracturing is carried out on a thick and hard top plate covering the rock burst coal seam mining area roadway group, the thick and hard top plate is integrally weakened and transformed, the roadway is located in a low-stress area, the mining area roadway is in a protected state, and the rock burst coal seam mining area group is protected. Therefore, the impact risk is effectively reduced, and the safety and stability of the roadway group in the long-term use period are improved.

Description

Technical Field

[0001] The invention relates to the technical field of safe mining of coal mines, and in particular to a method for preventing and controlling rock burst in a mining area tunnel group through distributed cutting and fracturing in a rock stratum tunnel. Background Art

[0002] Deep rock burst refers to a dynamic phenomenon that is easily caused by the unstable stress state of the coal rock mass during coal mining due to the complex geological conditions of deep coal seams and human factors. The mining area tunnel group is a group of tunnels that serve the mining area and are arranged to meet specific mining needs, including transportation tunnels, ventilation tunnels, drainage tunnels, etc. For the coal seam mining area tunnel group, the coal pillars between the tunnels are the main bearing body of deep rock burst, and the stress is highly concentrated. The coal pillars between the tunnels produce creep damage under the long-term bearing action, and their stability is greatly reduced, becoming the main factor inducing impact, and the impact risk increases. In the related technology, anchor rod support and reinforcement of coal pillars can improve the overall strength of coal pillars, but under the long-term bearing action, it is easy to have problems such as reduced anchoring force of anchor rods and unclear support effect, making it difficult to improve the stability of coal pillars in the later stage of long-term bearing. Summary of the invention

[0003] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0004] To this end, an embodiment of the present invention proposes a method for preventing and controlling rock bursts in a mining area tunnel group by distributed slit fracturing in a rock stratum tunnel. Slit fracturing is implemented above the coal seam where the tunnel group is located, so that the thick hard roof is weakened as a whole. The tunnels covered by the slit fracturing are in a low stress zone, so that the mining area tunnels are in a protected state, thereby effectively reducing the risk of impact and improving the safety and stability of the tunnel group 1 during long-term use.

[0005] The method for preventing rock burst in a mining area tunnel group by distributed fracturing in a rock tunnel according to an embodiment of the present invention comprises the following steps:

[0006] Step 1, excavating a pressure relief process tunnel: excavating a pressure relief process tunnel in the rock layer above the coal seam according to the bar chart of the tunnel group in the mining area;

[0007] Step 2, slit fracturing: a drilling site is set up on the pressure relief process tunnel, a pressure relief hole is drilled on at least one side of the drilling site, the pressure relief holes of the same drilling site cover the tunnel group in the width direction of the tunnel group, a plurality of pressure relief slits are cut in the pressure relief holes, and hydraulic fracturing is carried out at the pressure relief slits to form cracks;

[0008] Step 3, repeating step 2, setting up multiple drilling sites on the pressure relief process tunnel, and performing slit fracturing until the slit fracturing area is completed to cover the tunnel group.

[0009] The distributed slit fracturing method in the rock stratum tunnel of the embodiment of the present invention for preventing and controlling rock burst in the tunnel group of the mining area forms a slit fracturing area with dense cracks, thereby realizing dense slit fracturing in the rock stratum and unloading the rock stratum, and the unloading holes of the same drilling site cover the tunnel group in the width direction of the tunnel group 1, so that the slit fracturing area covers the tunnel group, thereby realizing dense slit fracturing of the thick hard roof covering the rock burst coal seam mining area tunnel group, so that the thick hard roof is weakened and transformed as a whole, and the tunnels covered by the slit fracturing are in a low stress zone, so that the mining area tunnels are in a protected state, thereby effectively reducing the risk of impact and improving the safety and stability of the tunnel group during long-term use.

[0010] In some embodiments, the pressure relief process lane is located in the middle of the lane group in the width direction; and / or the extension direction of the pressure relief process lane is parallel to the extension direction of the lane group.

[0011] In some embodiments, the bottoms of the two pressure relief holes in the same drilling site are located at least 15 m outside the tunnel group.

[0012] In some embodiments, in step 2, when cutting multiple pressure relief seams, the multiple pressure relief seams are cut sequentially in the direction from the bottom of the pressure relief hole to the hole mouth; and / or the distance between the pressure relief seam adjacent to the bottom of the pressure relief hole and the bottom of the pressure relief hole is 4-6m.

[0013] In some embodiments, in the depth direction of the pressure relief hole, the distance between two adjacent pressure relief seams is 6-8 m; and / or the length of the pressure relief seam is 0.5-1 m.

[0014] In some embodiments, in step 2, if the thickness of the rock formation is less than 10 m, the pressure relief seams are cut on both sides of the pressure relief hole in the horizontal direction at the same depth of the pressure relief hole; if the thickness of the rock formation is greater than 10 m, the pressure relief seams are cut on both sides of the pressure relief hole in the horizontal direction and on both sides in the up and down directions at the same depth of the pressure relief hole.

[0015] In some embodiments, the distance between the pressure relief seam adjacent to the pressure relief process tunnel and the pressure relief process tunnel is 4-6 m.

[0016] In some embodiments, in step 2 and step 3, a plurality of the pressure relief holes are drilled in sequence in a backward manner in the extension direction of the pressure relief process lane.

[0017] In some embodiments, in the extension direction of the pressure relief process lane, the distance between two adjacent pressure relief holes is 9-11 m.

[0018] In some embodiments, the fractures of adjacent drill sites are connected. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a plan view of the cutting and fracturing of the thick hard rock layer overlying the roadway group in the mining area;

[0020] Figure 2 This is a cross-sectional view of the cutting and fracturing of the thick hard rock layer overlying the tunnel group in the mining area;

[0021] Reference numerals:

[0022] Tunnel group 1, tunnel 11, pressure relief process tunnel 2, pressure relief hole 3, pressure relief seam 4, and fissure 5. DETAILED DESCRIPTION

[0023] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0024] Please refer to the attached Figure 1 and Figure 2 , a method for preventing and controlling rock burst in a mining area tunnel group by distributed cutting and fracturing in a rock tunnel according to an embodiment of the present invention is described in detail.

[0025] The method for preventing rock burst in a mining area tunnel group by distributed fracturing in a rock tunnel according to an embodiment of the present invention comprises the following steps:

[0026] Step 1, excavating the pressure relief process tunnel 2: excavating the pressure relief process tunnel 2 in the rock layer above the coal seam according to the histogram of the mining area tunnel group 1. The histogram of the mining area tunnel group 1 can show the overlying rock layer information of the tunnel group 1, such as the thickness and lithology of the overlying rock layer. Through the histogram of the mining area tunnel group 1, the rock layer characteristics above the tunnel group 1 can be determined, and then the pressure relief process tunnel 2 can be excavated in the thick hard sandstone layer.

[0027] Step 2, slit fracturing: a drilling site is set up on the pressure relief process tunnel 2, and a pressure relief hole 3 is drilled on at least one side of the drilling site. The pressure relief holes 3 of the same drilling site are arranged in the width direction of the tunnel group 1 (for example, Figure 1 A tunnel group 1 is covered in the left and right directions in the middle, a plurality of pressure relief seams 4 are cut in the pressure relief holes 3, and hydraulic fracturing is carried out at the pressure relief seams 4 to form cracks 5.

[0028] Step 3, repeat step 2, set up multiple drilling sites on the pressure relief process tunnel 2, and perform slit fracturing until the slit fracturing area covers the tunnel group 1.

[0029] The distributed cutting and fracturing method for preventing and controlling rock burst in the mining area roadway group of the embodiment of the present invention is to excavate a pressure relief process roadway 2 above the coal seam where the roadway group 1 is located, drill a plurality of pressure relief holes 3 in the length direction of the pressure relief process roadway 2, thereby cutting out pressure relief seams 4 in the length direction of the pressure relief holes 3 and carrying out hydraulic fracturing to form fissures 5, forming a cutting and fracturing area, wherein the cutting and fracturing area has dense fissures 5, thereby realizing dense cutting and fracturing on the rock formation and realizing pressure relief on the rock formation, and the pressure relief holes 3 in the same drilling field are arranged in the width direction of the roadway group 1 (for example, Figure 1 The tunnel group 1 is covered on the left and right directions in the middle (in the left and right directions), so that the cutting and fracturing area covers the tunnel group 1, thereby realizing intensive cutting and fracturing of the thick hard roof covered on the tunnel group 1 in the impact ground pressure coal seam mining area, so that the thick hard roof is weakened and transformed as a whole, and the tunnel 11 covered by the cutting and fracturing is in a low stress area, so that the mining area tunnel 11 is in a protected state, thereby effectively reducing the impact risk and improving the safety and stability of the tunnel group 1 during long-term use.

[0030] like Figure 2 As shown, the pressure relief process tunnel 2 is located 10m above the coal seam.

[0031] In some embodiments, the pressure relief process tunnel 2 is located in the middle of the tunnel group 1 in the width direction, thereby shortening the length of each pressure relief hole 3 and reducing the construction difficulty of the pressure relief hole 3, thereby improving the construction efficiency of the distributed cutting and fracturing method for preventing and controlling rock burst in the mining area tunnel group 1 in the rock formation tunnel 11 of the embodiment of the present invention.

[0032] The pressure relief process lane 2 is located in the middle of the lane group 1 in the width direction, and then in step 2, pressure relief holes 3 are drilled on both sides of the drilling site. That is, pressure relief holes 3 are drilled on both sides of the pressure relief process lane 2 in the width direction.

[0033] In some embodiments, the pressure relief process tunnel 2 is parallel to the tunnel 11 of the tunnel group 1, and the pressure relief hole 3 is perpendicular to the tunnel 11. The multiple pressure relief holes 3 are more evenly distributed relative to the tunnel group 1, and the fissures 5 are more evenly distributed, so that the thick hard roof is weakened as a whole, thereby further reducing the impact risk of the mining area tunnel 11. In addition, the pressure relief process tunnel 2 is parallel to the tunnel 11 of the tunnel group 1, so that the lengths of the multiple pressure relief holes 3 on the pressure relief process tunnel 2 are the same, so that the consistency of the multiple pressure relief holes 3 is large, which can further reduce the construction difficulty of the pressure relief holes 3, improve the construction efficiency of the pressure relief holes 3, and further improve the construction efficiency of the distributed cutting and fracturing method for preventing and controlling rock burst in the mining area tunnel group according to the embodiment of the present invention.

[0034] If the length of the pressure relief process tunnel 2 is equal to or longer than that of the tunnel 11 of the tunnel group 1, the cutting and fracturing area covers the tunnel group 1 in the length direction of the tunnel group 1 and also in the length direction of the tunnel 11, so that the rock formation area above the tunnel group 1 is weakened, and the tunnel group 1 as a whole is in a low stress zone, thereby ensuring that the mining area tunnel 11 is in a protected state and effectively reducing the impact risk.

[0035] In some embodiments, the bottoms of two pressure relief holes 3 in the same drilling site are located at least 15m outside the tunnel group 1, thereby ensuring that the cracks 5 on the pressure relief seams 4 at the bottom of the pressure relief holes 3 can be located outside the tunnel group 1, completely covering the tunnel group 1, and covering part of the area outside the tunnel group 1, thereby ensuring that the dense cutting and fracturing area on the thick hard roof covers the tunnel group 1 and part of the area outside the tunnel group 1, and further ensuring that the overall weakened area of ​​the thick hard roof covers the tunnel group 1, thereby ensuring that the mining area tunnels 11 are in a protected state, thereby effectively reducing the impact risk and improving the safety and stability of the tunnel group 1 during long-term use.

[0036] In some embodiments, the bottoms of the two pressure relief holes 3 in the same drilling site are located 15 m, 16 m, 17 m, 17.5 m or 18 m outside the tunnel group 1 .

[0037] In this embodiment, Figure 1 and Figure 2 As shown, the tunnel group 1 includes four tunnels 11. The tunnel 11 is 5m wide and the coal pillars between the tunnels are 30m. The total width of the tunnel group 1 is 110m. The pressure relief process tunnel 2 is 5m wide and the pressure relief hole 3 is 70m deep. The bottom of the pressure relief hole 3 is located 17.5m outside the tunnel group 1.

[0038] It should be noted that the number, width and length of the lanes 11 of the lane group 1 are not limited in this embodiment.

[0039] In some embodiments, in step 2, when cutting multiple pressure relief slits 4, multiple pressure relief slits 4 are cut in sequence from the bottom of the pressure relief hole 3 to the hole mouth. The distance between the pressure relief slit 4 adjacent to the bottom of the pressure relief hole 3 and the bottom of the pressure relief hole 3 is 4-6m.

[0040] For example, the first pressure relief seam 4 is cut at a position 4-6 m away from the bottom of the pressure relief hole 3, and then hydraulic fracturing is carried out at the first seam, and then the seam cutting device is moved backward to cut the second pressure relief seam 4, and so on. The backward moving seam cutting device is highly safe and easy to operate.

[0041] For example, the distance between the pressure relief slit 4 adjacent to the bottom of the pressure relief hole 3 and the bottom of the pressure relief hole 3 is 4 m, 5 m, 5.5 m or 6 m.

[0042] In this embodiment, the distance between the pressure relief slit 4 adjacent to the bottom of the pressure relief hole 3 and the bottom of the pressure relief hole 3 is 5 m.

[0043] In some embodiments, in the depth direction of the pressure relief hole 3, that is, in Figure 1 and Figure 2 In the left and right directions of the figure, the distance between two adjacent pressure relief seams 4 is 6-8m, thereby providing space for hydraulic fracturing on two adjacent pressure relief seams 4, avoiding the connection between the cracks 5 on two adjacent pressure relief seams 4, maintaining pressure for the next hydraulic fracturing process, and avoiding water leakage from the formed cracks 5 during the next hydraulic fracturing process to affect the forming of the cracks 5, thereby ensuring the forming effect of the cracks 5 and the density of the cracks 5 in the dense cutting fracturing area.

[0044] Specifically, in the depth direction of the pressure relief hole 3, the distance between two adjacent pressure relief seams 4 is 7 m.

[0045] In some embodiments, the length of the pressure relief seam 4 is 0.5-1 m.

[0046] In this embodiment, the length of the horizontal pressure relief seam 4 is 0.5 m.

[0047] In some embodiments, in step 2, if the thickness of the rock formation is less than 10 m, at the same depth position of the pressure relief hole 3, pressure relief seams 4 are cut on both sides of the pressure relief hole 3 in the horizontal direction, that is, Figure 1 In the process, horizontal pressure relief seams 4 are cut on both sides of the pressure relief hole 3 in the front-back direction, and then hydraulic fracturing is carried out on the pressure relief seams 4. If the thickness of the rock formation is greater than 10m, at the same depth position of the pressure relief hole 3, pressure relief seams 4 are cut on both sides of the pressure relief hole 3 in the horizontal direction and in the up-down direction, that is, horizontal pressure relief seams 4 are cut on both sides of the pressure relief hole 3 in the front-back direction, and vertical pressure relief seams 4 are cut on both sides of the pressure relief hole 3 in the up-down direction, and then hydraulic fracturing is carried out on the pressure relief seams 4.

[0048] Different rock formation thicknesses create different impact hazards. The distributed slit fracturing method for preventing and controlling rock burst in the mining area tunnel group 1 in the rock formation tunnel 11 of the embodiment of the present invention selects whether to perform slit fracturing in the upper and lower directions of the pressure relief hole 3 according to the different rock formation thicknesses. That is, for thick rock formations, slit fracturing is performed in the upper and lower directions of the pressure relief hole 3, then the density of the cracks 5 is large and the slit fracturing is more dense, thereby having a better effect on weakening the rock formation as a whole, ensuring that the mining area tunnel 11 can still be in a protected state when the rock formation is relatively thick, thereby effectively reducing the impact hazard.

[0049] Specifically, the frosted jet technology is used for cutting.

[0050] Hydraulic fracturing is carried out on each pressure relief joint 4 from different angles, thereby forming cracks 5 with different extending directions.

[0051] In some embodiments, the distance between the slit adjacent to the pressure relief process tunnel 2 and the pressure relief process tunnel 2 is 4-6 m.

[0052] Specifically, the distance between the cut adjacent to the pressure relief process tunnel 2 and the pressure relief process tunnel 2 is 5m.

[0053] In some embodiments, in step 2 and step 3, a plurality of pressure relief holes 3 are drilled in sequence in a backward manner along the extension direction of the pressure relief process tunnel 2 .

[0054] In the extension direction of the pressure relief process tunnel 2, the distance between two adjacent pressure relief holes 3 is 9-11m.

[0055] For example, the first drilling site is set in the pressure relief process lane 2, and a pressure relief hole 3 is drilled on both sides of the first drilling site. Then, the drilling device is retreated 9-11m, and a second drilling site is set there, and a pressure relief hole 3 is drilled on both sides of the second drilling site, and so on. The retreating mobile drilling device is highly safe and easy to operate for drilling.

[0056] Specifically, in the extending direction of the pressure relief process tunnel 2, the distance between two adjacent pressure relief holes 3 is 9m, 10m or 11m.

[0057] In this embodiment, in the extending direction of the pressure relief process tunnel 2, the distance between two adjacent pressure relief holes 3 is 10m.

[0058] In some embodiments, the cracks 5 of adjacent drill sites are connected. At least one crack 5 on one borehole on the same side of two adjacent drill sites is connected to at least one crack 5 on another borehole. Figure 1 In the embodiment, for the two right boreholes of the two rearmost drilling sites, at least one fissure 5 on one borehole is connected to at least one fissure 5 on another borehole, Figure 1 It can be seen that the cracks on the rightmost pressure relief seam 4 are connected.

[0059] The fissures 5 of two adjacent drilling sites are connected to avoid the formation of a fracturing blind area, thereby avoiding a pressure relief blind area, thereby further ensuring that the thick hard roof is weakened and transformed as a whole, ensuring that the mining area tunnel 11 is in a protected state, thereby effectively reducing the impact risk.

[0060] Therefore, through the distributed cutting and fracturing method for preventing and controlling rock burst in the mining area tunnel group in the embodiment of the present invention, intensive cutting and fracturing are carried out on the thick hard roof overlying the coal seam in the pressure relief process tunnel, thereby reducing the original rock stress and structural stress levels above the mining area tunnel group area, so that the mining area tunnel group area is in a pressure relief protection zone, effectively reducing the possibility of rock burst during the use of the rock burst coal seam mining area tunnel group, and ensuring the safety and stability of the mining area tunnel group 1 during use.

[0061] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0062] 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 the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0063] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0064] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0065] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" etc. mean 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 invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics 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.

[0066] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A method for preventing rock burst in a mining area by distributed fracturing in a rock tunnel, characterized in that: The following steps are involved: Step 1, excavating a pressure relief process tunnel (2): excavating a pressure relief process tunnel (2) in the rock layer above the coal seam according to the column chart of the tunnel group (1) in the mining area; Step 2, slit fracturing: a drilling site is set up on the pressure relief process tunnel (2), a pressure relief hole (3) is drilled on at least one side of the drilling site, the pressure relief holes (3) of the same drilling site cover the tunnel group (1) in the width direction of the tunnel group (1), a plurality of pressure relief slits (4) are cut in the pressure relief holes (3), and hydraulic fracturing is carried out at the pressure relief slits (4) to form cracks (5); Step 3, repeating step 2, setting up multiple drilling sites on the pressure relief process tunnel (2), and performing slit fracturing until the slit fracturing area is completed to cover the tunnel group (1).

2. The method for preventing rock burst in a mining area tunnel group by distributed fracturing in a rock tunnel according to claim 1 is characterized in that: The pressure relief process lane (2) is located in the middle of the lane group (1) in the width direction; and / or the extension direction of the pressure relief process lane (2) is parallel to the extension direction of the lane group (1).

3. The method for preventing rock burst in a mining area by distributed fracturing in a rock tunnel according to claim 1, characterized in that: The bottoms of the two pressure relief holes (3) in the same drilling site are located at least 15 m outside the tunnel group (1).

4. The method for preventing rock burst in a mining area by distributed fracturing in a rock tunnel according to claim 1, characterized in that: In step 2, when cutting a plurality of the pressure relief slits (4), the plurality of the pressure relief slits (4) are cut in sequence in the direction from the bottom of the pressure relief hole (3) to the hole mouth; and / or the distance between the pressure relief slit (4) adjacent to the bottom of the pressure relief hole (3) and the bottom of the pressure relief hole (3) is 4-6 m.

5. The method for preventing rock burst in a mining area by distributed fracturing in a rock tunnel according to claim 1, characterized in that: In the depth direction of the pressure relief hole (3), the distance between two adjacent pressure relief seams (4) is 6-8 m; and / or the length of the pressure relief seam (4) is 0.5-1 m.

6. The method for preventing rock burst in a mining area by distributed fracturing in a rock tunnel according to claim 1, characterized in that: In step 2, if the thickness of the rock formation is less than 10 m, the pressure relief seams (4) are cut out on both sides of the pressure relief hole (3) in the horizontal direction at the same depth position of the pressure relief hole (3); if the thickness of the rock formation is greater than 10 m, the pressure relief seams (4) are cut out on both sides of the pressure relief hole (3) in the horizontal direction and in the up-down direction at the same depth position of the pressure relief hole (3).

7. The method for preventing rock burst in a mining area by distributed fracturing in a rock tunnel according to claim 1, characterized in that: The distance between the pressure relief joint adjacent to the pressure relief process tunnel (2) and the pressure relief process tunnel (2) is 4-6m.

8. The method for preventing rock burst in a mining area by distributed fracturing in a rock tunnel according to claim 1, characterized in that: In step 2 and step 3, a plurality of pressure relief holes (3) are drilled in sequence in a backward manner according to the extension direction of the pressure relief process tunnel (2).

9. The method for preventing rock burst in a mining area by distributed fracturing in a rock tunnel according to claim 1, characterized in that: In the extension direction of the pressure relief process tunnel (2), the distance between two adjacent pressure relief holes (3) is 9-11 m.

10. The method for preventing rock burst in a mining area tunnel group by distributed fracturing in a rock tunnel according to claim 9, characterized in that: The fissures (5) of adjacent drilling sites are connected.

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