Blasting scour prevention method for distributed horizontal holes in overlying rock roadway of roadway in full coal mining area

Abstract

The invention discloses a blasting scour prevention method for distributed horizontal holes in an overlying rock roadway of a roadway in a full coal mining area, which comprises the following steps of: determining the position of an overlying thick and hard sandstone layer according to geological data of a roadway group; a pressure relief roadway is tunneled in the position of the overlying strata in the extending direction of the mining area roadway, and a pressure relief area is formed on at least one side of the pressure relief roadway; and blasting parameters for the pressure relief area are determined, blasting preparation is conducted on the basis of the blasting parameters so that blasting of the pressure relief area can be implemented, and the blasting parameters comprise drilling parameters and charging parameters. According to the blasting anti-impact method for the distributed horizontal holes in the overlying rock roadway of the full coal mining area, the hard roof above the mining area roadway can be blasted, the primary rock stress level and the tectonic stress level of the area above the mining area roadway are reduced, the mining area roadway is located in a pressure relief protection area, and the safety of the mining area roadway is improved. Therefore, the probability of rock burst during use of the mining area roadway is effectively reduced, and safe use of the mining area roadway is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of safe coal mining methods, and in particular to a distributed horizontal hole blasting anti-bumping method in an overburden rock lane in a full coal mining area lane. Background Art

[0002] The deep coal seam tunnel group with rock bursts uses the coal pillars between tunnels as the main bearing body. The coal pillars between tunnels bear great pressure from the surrounding rock strata, which makes the internal pressure of the coal pillars highly concentrated. Under the action of long-term bearing, creep damage occurs inside the coal pillars between tunnels, gradually weakening the bearing capacity of the coal pillars, resulting in a significant decrease in the stability of the coal pillars between tunnels, which becomes the main factor inducing rock bursts. The risk of rock bursts and low pressure increases, posing a serious threat to the safe use of tunnels in the mining area. 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 impact of distributed horizontal holes in overlying rock tunnels in all coal mining area tunnels. A pressure relief tunnel is excavated in advance at the location of the overlying rock stratum, blasting preparations are carried out in the pressure relief tunnel, and blasting is carried out on the hard roof above the mining area tunnels to reduce the original rock stress and structural stress levels in the area above the mining area tunnels, so that the mining area tunnels are in a pressure relief protection area, thereby effectively reducing the probability of impact ground pressure during the use of the mining area tunnels and ensuring the safe use of the mining area tunnels.

[0005] The method for preventing impact by distributed horizontal hole blasting in the overburden roadway of the whole coal mining area according to the embodiment of the present invention comprises the following steps:

[0006] Determine the location of the overlying rock layer based on the geological data of the tunnel group;

[0007] Excavating a pressure relief tunnel in the overlying rock strata along the extension direction of the mining area tunnel, and forming a pressure relief area on at least one side of the pressure relief tunnel;

[0008] Determine blasting parameters for the pressure relief zone, and perform blasting preparation based on the blasting parameters to implement blasting in the pressure relief zone, wherein the blasting parameters include drilling parameters and charging parameters.

[0009] In some embodiments, the drilling parameters include the number of blasting holes, and the number of the blasting holes is multiple, and the multiple blasting holes are arranged at intervals along the extension direction of the pressure relief tunnel.

[0010] In some embodiments, at least one of the blasting holes is a second blasting hole, and at least one of the blasting holes is a first blasting hole. The second blasting hole and the first blasting hole form a hole group. There are multiple hole groups, and the multiple hole groups are evenly arranged along the extension direction of the pressure relief tunnel.

[0011] In some embodiments, the distance between two adjacent hole groups is 9m to 11m.

[0012] In some embodiments, the projection of the pressure relief tunnel on the horizontal plane forms a pressure relief tunnel projection area, the tunnel group includes a plurality of parallel mining tunnels, the projection of the tunnel group on the horizontal plane forms a tunnel group projection area, the projection of the second blasting hole on the horizontal plane forms a second hole projection area, and the projection of the first blasting hole on the horizontal plane forms a first hole projection area; the drilling parameters also include the direction of the blasting hole, and the direction of the blasting hole is set as follows: the second hole projection area and the first hole projection area are both pointed from the pressure relief tunnel projection area to the tunnel group projection area, and the length directions of the second hole projection area and the first hole projection area are both perpendicular to the length direction of the tunnel group projection area.

[0013] In some embodiments, the tunnel group projection area includes a first tunnel projection area arranged close to the pressure relief tunnel projection area and a second tunnel projection area arranged away from the pressure relief tunnel projection area, and the drilling parameters also include the depth of the blasting hole, and the depth of the blasting hole is set as follows: the second hole projection area extends from the pressure relief tunnel projection area to the side of the second tunnel projection area away from the pressure relief tunnel projection area, and the first hole projection area extends from the pressure relief tunnel projection area to the side of the first tunnel projection area away from the pressure relief tunnel projection area.

[0014] In some embodiments, the second hole projection area has a first edge arranged away from the pressure relief lane projection area, the second lane projection area has a second edge arranged away from the pressure relief lane projection area, and the distance between the first edge and the second edge is 14m to 16m.

[0015] In some embodiments, the depth of the first blasting hole is 18m-24m, and the depth of the second blasting hole is 58m-68m.

[0016] In some embodiments, the charging parameters include charging quantity and charging length. The charging quantity of the first blasting hole is 40kg-60kg, the charging length of the first blasting hole is 12m-16m, the charging quantity of the second blasting hole is 80kg-100kg, and the charging length of the second blasting hole is 40m-44m.

[0017] In some embodiments, the distance between the bottom plate of the pressure relief tunnel and the coal seam is 8m to 12m.

[0018] The distributed horizontal hole blasting anti-burst method in the overburden roadway of the full coal mining area of ​​the embodiment of the present invention is to excavate a pressure relief roadway in advance at the position of the overburden rock layer (i.e., the thick, hard and fine sandstone layer), and form a pressure relief zone for the mining area roadway on both sides of the pressure relief roadway. Blasting preparation is carried out in the pressure relief roadway, and blasting is carried out on the pressure relief zone to reduce the original rock stress and structural stress level of the hard roof above the mining area roadway, so that the mining area roadway is in the pressure relief protection area, thereby effectively reducing the probability of rock burst during the use of the mining area roadway and ensuring the safe use of the mining area roadway. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a projection view of a mining area tunnel, a pressure relief tunnel and a blasting hole on a horizontal plane according to an embodiment of the present invention.

[0020] Figure 2 is along Figure 1 Sectional view of section Ⅰ-Ⅰ.

[0021] Figure 3 It is a schematic flow chart of a method for preventing impact by distributed horizontal hole blasting in an overburden rock tunnel in a full coal mining area according to an embodiment of the present invention.

[0022] Reference numerals:

[0023] 1. Overburden strata; 11. Pressure relief area;

[0024] 2. Mining area tunnel; 21. First tunnel; 211. First tunnel projection area; 22. Second tunnel; 221. Second tunnel projection area; 222. Second edge;

[0025] 3. Pressure relief tunnel; 31. Pressure relief tunnel projection area;

[0026] 41. First blasting hole; 411. First hole projection area; 42. Second blasting hole; 421. Second hole projection area; 422. First edge. DETAILED DESCRIPTION

[0027] 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.

[0028] like Figures 1 to 3 As shown, the distributed horizontal hole blasting anti-bumping method in the overburden roadway of the whole coal mining area of ​​the embodiment of the present invention comprises the following steps:

[0029] S1: Determine the location of the overlying rock layer 1 based on the geological data of the tunnel group;

[0030] S2: excavating a pressure relief tunnel 3 in the overlying rock layer 1 along the extension direction of the mining area tunnel 2, and forming a pressure relief area 11 on at least one side of the pressure relief tunnel 3;

[0031] S3: Determine blasting parameters for the pressure relief zone 11, and perform blasting preparation based on the blasting parameters to implement blasting in the pressure relief zone 11. The blasting parameters include drilling parameters and charging parameters.

[0032] According to the distributed horizontal hole blasting anti-bumping method in the overlying rock tunnel of the full coal mining area tunnel of the embodiment of the present invention, a pressure relief tunnel 3 is excavated in advance at the position of the overlying rock layer 1 (i.e., the thick, hard and fine sandstone layer), and pressure relief areas 11 for the mining area tunnel 2 are formed on both sides of the pressure relief tunnel 3. Blasting preparation is carried out in the pressure relief tunnel 3, and blasting is carried out on the pressure relief area 11 to reduce the original rock stress and structural stress level of the hard roof above the mining area tunnel 2, so that the mining area tunnel 2 is in the pressure relief protection area, thereby effectively reducing the probability of rock burst during the use of the mining area tunnel 2 and ensuring the safe use of the mining area tunnel 2.

[0033] Optionally, the geological data is a drill hole histogram.

[0034] The borehole column chart can clearly display the lithology, thickness, structure and other information of the rock layer, so that construction personnel can understand the contact relationship and distance between the overlying rock layer 11 and the coal seam, so as to make more comprehensive blasting preparations to ensure the safety of the blasting operation.

[0035] like Figure 1 and Figure 2 As shown, the coal seam, mudstone layer and fine sandstone layer are arranged from bottom to top, the height of the coal seam is 5.8m, the height of the mudstone layer is 3.9m, and the height of the fine sandstone layer is 12.3m; the mining area tunnel 2 is arranged in the coal seam to facilitate transportation, ventilation, etc. of coal seam mining, the width of the mining area tunnel 2 is 5m, the number of mining area tunnels 2 is four, the four mining area tunnels 2 are arranged in parallel, the width of the coal pillars between the mining area tunnels 2 is 30m, that is, the distance between two adjacent mining area tunnels 2 is 30m; the pressure relief tunnel 3 is arranged in the fine sandstone layer, and the fine sandstone layer is the above-mentioned overlying rock layer 1.

[0036] By drilling blasting holes towards the pressure relief areas 11 on both sides of the pressure relief tunnel 3 and performing blasting based on the blasting holes, it is possible to relieve pressure on the hard roof above the mining tunnel 2, so that the mining tunnel 2 is in a pressure relief protection area, thereby reducing the probability of rock burst during the use of the mining tunnel 2.

[0037] In some embodiments, Figure 1 and Figure 2 As shown, the drilling parameters also include the number of blasting holes. The number of blasting holes is multiple, and the multiple blasting holes are arranged at intervals along the extension direction of the pressure relief tunnel 3.

[0038] By setting up multiple blasting holes, intensive deep hole blasting can be attempted on the overlying rock layer 1. The blasting range can cover the tunnel group, so that multiple mining tunnels 2 are all in the low stress zone, avoiding stress concentration and causing increased impact risk, thereby improving the safety of the use of the mining tunnels 2.

[0039] In some embodiments, at least one blasting hole is a second blasting hole 42 , and at least one blasting hole is a first blasting hole 41 . The second blasting hole 42 and the first blasting hole 41 form a hole group. There are multiple hole groups, and the multiple hole groups are evenly arranged along the extension direction of the pressure relief tunnel 3 .

[0040] Since there are many tunnels 2 in the mining area and the blasting depth is long, if only one blasting hole is set, the charging length of the blasting hole will be too long, resulting in the sealing length being unable to meet the blasting requirements, forming a pressure relief blind area.

[0041] Through the above settings, the depths of the second blasting hole 42 and the first blasting hole 41 can be reasonably set, the pre-cracking range of blasting can be better controlled, the pressure relief area fully covers the mining area tunnel 2, and effective pressure relief is achieved in the mining area tunnel group area.

[0042] Of course, in other embodiments, when the number of the mining area tunnels 2 is more than four, the number of blasting holes included in the hole group may also be increased, so as to further control the pre-splitting range to achieve a better pre-splitting effect.

[0043] Optionally, after the excavation of the pressure relief tunnel 3 is completed, the blasting of the pressure relief areas 11 on both sides is carried out in a backward operation mode; first, a drilling site is set up in the pressure relief tunnel 3, and a group of holes are drilled from the drilling site to the pressure relief areas 11 on both sides, and blasting is carried out based on the hole groups; after the blasting is completed, the drilling site is moved backward along the pressure relief tunnel 3 (the excavation direction of the pressure relief tunnel 3 is set to the front), and blasting operations are carried out at the next position until all pre-cracking work on the hard roof above the mining area tunnel 2 is completed.

[0044] In some embodiments, the distance between two adjacent hole groups is 9 m to 11 m.

[0045] By imposing the above restrictions on the distance between two adjacent hole groups, it can be ensured that the cracks generated by the two adjacent hole groups are interconnected, reducing the risk of pre-cracking blind areas and ensuring the continuity of the pressure relief zone 11, thereby forming a continuous pressure relief protection zone on the upper side of the mining area tunnel 2 and reducing the probability of rock burst during the use of the mining area tunnel 2.

[0046] Preferably, the distance between two adjacent hole groups is 10 m.

[0047] As an example, Figure 1 and Figure 2As shown, each hole group includes two blasting holes, namely the second blasting hole 42 and the first blasting hole 41. The second blasting hole 42 and the first blasting hole 41 are both horizontal holes and are parallel to each other. The projections of the second blasting hole 42 and the first blasting hole 41 on the vertical plane coincide with each other (wherein the vertical plane is perpendicular to the horizontal plane).

[0048] Optionally, the distance between the second blasting hole 42 and the first blasting hole 41 is 0.5 m to 1 m.

[0049] In some embodiments, Figure 1 and Figure 2 As shown, the projection of the pressure relief tunnel 3 on the horizontal plane forms a pressure relief tunnel projection area 31, the tunnel group includes a plurality of mining tunnels 2 parallel to each other, the projection of the tunnel group on the horizontal plane forms a tunnel group projection area, the projection of the second blasting hole 42 on the horizontal plane forms a second hole projection area 421, and the projection of the first blasting hole 41 on the horizontal plane forms a first hole projection area 411; the drilling parameters include the direction of the blasting hole, and the setting method of the direction of the blasting hole is: the second hole projection area 421 and the first hole projection area 411 are both pointed from the pressure relief tunnel projection area 31 to the tunnel group projection area, and the length directions of the second hole projection area 421 and the first hole projection area 411 are both perpendicular to the length direction of the tunnel group projection area.

[0050] It is known that the area directly above the mining tunnel 2 is its support pressure peak area.

[0051] Through the above arrangement, the first blasting hole 41 and the second blasting hole 42 can extend to the top of the different mining area tunnels 2 at the shortest depth, so that the cracks generated by the blasting can cover the supporting pressure peak area of ​​the different mining area tunnels 2, which is more conducive to the weakening and transformation of the hard roof above the mining area tunnel 2, so that the mining area tunnel 2 is in a low stress area, thereby reducing the impact risk.

[0052] like Figure 1 and Figure 2 As shown, the number of mining area tunnels 2 is four, and the projections of the four mining area tunnels 2 on the horizontal plane are divided into two groups. The projections of the two groups of mining area tunnels 2 are symmetrically arranged on both sides of the pressure relief tunnel projection area 31. The projections of the two mining area tunnels 2 located on the same side of the pressure relief tunnel projection area 31 successively form a first tunnel projection area 211 and a second tunnel projection area 221 in the direction away from the pressure relief tunnel projection area 31. The mining area tunnel 2 corresponding to the first tunnel projection area 211 is the first tunnel 21, and the mining area tunnel 2 corresponding to the second tunnel projection area 221 is the second tunnel 22.

[0053] In some embodiments, the drilling parameters also include the depth of the blasting hole, and the depth of the blasting hole is set as follows: the second hole projection area 421 extends from the pressure relief tunnel projection area 31 to the side of the second tunnel projection area 221 away from the pressure relief tunnel projection area 31, and the first hole projection area 411 extends from the pressure relief tunnel projection area 31 to the side of the first tunnel projection area 211 away from the pressure relief tunnel projection area 31.

[0054] Through the above arrangement, the first blasting hole 41 can extend to the top of the first tunnel 21, and the second blasting hole 42 can extend to the top of the second tunnel 22. The cracks formed by blasting the second blasting hole 42 and the first blasting hole 41 can cover the first tunnel 21 and the second tunnel 22, so that the tunnel group formed by multiple mining tunnels 2 is in the pressure relief protection zone, reducing the probability of impact ground pressure during the use of the mining tunnel 2 and improving the safety of the use of the mining tunnel 2.

[0055] In some embodiments, the second hole projection area 421 has a first edge 422 arranged away from the pressure relief lane projection area 31, and the second lane projection area 221 has a second edge 222 arranged away from the pressure relief lane projection area 31, and the distance between the first edge 422 and the second edge 222 is 14m to 16m.

[0056] Through the above arrangement, the cracks generated by blasting the second blasting hole 42 can completely cover the bearing pressure peak area above the second tunnel 22. At the same time, the depth of the second blasting hole 42 is relatively appropriate, preventing the difficulty of drilling construction from increasing due to the greater depth of the second blasting hole 42.

[0057] Preferably, the distance between the first edge 422 and the second edge 222 is 15 m.

[0058] In some embodiments, the depth of the first blasting hole 41 is 18 m to 24 m, and the depth of the second blasting hole 42 is 58 m to 68 m.

[0059] It is known that the width of the mining area tunnel 2 is 5 m, and the distance between two adjacent mining area tunnels 2 is 30 m.

[0060] Through the above arrangement, the depths of the first blasting hole 41 and the second blasting hole 42 are relatively appropriate, that is, the cracks produced by the blasting of the explosives in the first blasting hole 41 can completely cover the peak support pressure area above the first tunnel 21, and the cracks produced by the blasting of the explosives in the second blasting hole 42 can completely cover the peak support pressure area above the second tunnel 22, so that multiple mining area tunnels 2 are all in the pressure relief protection area, reducing the probability of impact ground pressure.

[0061] Preferably, the depth of the first blasting hole 41 is 21 m, and the depth of the second blasting hole 42 is 63 m.

[0062] In some embodiments, the charging parameters include charging quantity and charging length. The charging quantity of the first blasting hole 41 is 40kg-60kg, the charging length of the first blasting hole 41 is 12m-16m, the charging quantity of the second blasting hole 42 is 80kg-100kg, and the charging length of the second blasting hole 42 is 40m-44m.

[0063] Through the above arrangement, the explosive in the first blasting hole 41 can completely cover the first tunnel 21 along the width direction, and the explosive in the second blasting hole 42 can completely cover the second tunnel 22 along the width direction. Multiple hole groups are evenly arranged along the extension direction of the mining area tunnel 2, so that a complete pressure relief protection zone can be formed above the mining area tunnel 2 to ensure the safe use of the mining area tunnel 2.

[0064] Preferably, the charge amount of the first blasting hole 41 is 50 kg, and the charge length of the first blasting hole 41 is 14 m, then the sealing length of the first blasting hole 41 is 7 m; the charge amount of the second blasting hole 42 is 100 kg, and the charge length of the second blasting hole 42 is 42 m, then the sealing length of the second blasting hole 42 is 21 m.

[0065] By setting a suitable sealing length, it is possible to ensure that the explosives react fully in the first blasting hole 41 and the second blasting hole 42, thereby improving the utilization rate of the explosive energy and saving costs.

[0066] In some embodiments, the distance between the bottom plate of the pressure relief tunnel 3 and the coal seam is 8m to 12m.

[0067] By imposing the above-mentioned restrictions on the height of the pressure relief tunnel 3, the distance between the blasting position and the coal seam can be limited, so that the cracks generated by the blasting can spread more effectively in the overlying rock layer 1, and the crack range is larger and more uniform, thereby achieving a better pressure relief effect and reducing the probability of rock burst. At the same time, the stability of the coal seam during the blasting process can be guaranteed to prevent the blasting from causing the collapse of the coal seam tunnel.

[0068] Preferably, the distance between the bottom plate of the pressure relief tunnel 3 and the coal seam is 10 m.

[0069] 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.

[0070] 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.

[0071] 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.

[0072] 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.

[0073] 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.

[0074] 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 distributed horizontal hole blasting anti-bumping method in the overburden rock of the whole coal mining area roadway, characterized in that: The number of the mining area tunnels (2) is multiple, and the multiple mining area tunnels (2) form a tunnel group. The distributed horizontal hole blasting anti-bumping method in the overlying rock tunnel of the full coal mining area tunnel comprises the following steps: Determine the location of the overlying rock layer (1) based on the geological data of the tunnel group; A pressure relief tunnel (3) is excavated in the overlying rock layer (1) along the extension direction of the mining area tunnel (2), and a pressure relief area (11) is formed on at least one side of the pressure relief tunnel (3); Blasting parameters for the pressure relief zone (11) are determined, and blasting preparation is performed based on the blasting parameters to implement blasting of the pressure relief zone (11), wherein the blasting parameters include drilling parameters and charging parameters.

2. The method for preventing impact by distributed horizontal hole blasting in overburden roadway of full coal mining area according to claim 1 is characterized in that: The drilling parameters include the number of blasting holes, the number of the blasting holes is multiple, and the multiple blasting holes are arranged at intervals along the extension direction of the pressure relief tunnel (3).

3. The method for preventing impact by distributed horizontal hole blasting in overburden roadway of full coal mining area according to claim 2 is characterized in that: At least one of the blasting holes is a second blasting hole (42), and at least one of the blasting holes is a first blasting hole (41). The second blasting hole (42) and the first blasting hole (41) form a hole group. There are multiple hole groups, and the multiple hole groups are evenly arranged along the extension direction of the pressure relief tunnel (3).

4. The method for preventing impact by distributed horizontal hole blasting in overburden roadway of full coal mining area according to claim 3 is characterized in that: The distance between two adjacent hole groups is 9m to 11m.

5. The method for preventing impact by distributed horizontal hole blasting in overburden roadway of full coal mining area according to claim 3 is characterized in that: The projection of the pressure relief tunnel (3) on the horizontal plane forms a pressure relief tunnel projection area (31), the tunnel group includes a plurality of mining tunnels (2) parallel to each other, the projection of the tunnel group on the horizontal plane forms a tunnel group projection area, the projection of the second blasting hole (42) on the horizontal plane forms a second hole projection area (421), and the projection of the first blasting hole (41) on the horizontal plane forms a first hole projection area (411); The drilling parameters also include the direction of the blasting hole. The direction of the blasting hole is set in the following manner: the second hole projection area (421) and the first hole projection area (411) are both directed from the pressure relief tunnel projection area (31) to the tunnel group projection area, and the length directions of the second hole projection area (421) and the first hole projection area (411) are both perpendicular to the length direction of the tunnel group projection area.

6. The method for preventing impact by distributed horizontal hole blasting in overburden roadway of full coal mining area according to claim 5 is characterized in that: The tunnel group projection area includes a first tunnel projection area (211) arranged close to the pressure relief tunnel projection area (31) and a second tunnel projection area (221) arranged away from the pressure relief tunnel projection area (31); the drilling parameters also include the depth of the blasting hole; the depth of the blasting hole is set in the following manner: the second hole projection area (421) extends from the pressure relief tunnel projection area (31) to a side of the second tunnel projection area (221) away from the pressure relief tunnel projection area (31); and the first hole projection area (411) extends from the pressure relief tunnel projection area (31) to a side of the first tunnel projection area (211) away from the pressure relief tunnel projection area (31).

7. The method for preventing impact by distributed horizontal hole blasting in overburden roadway of full coal mining area according to claim 6 is characterized in that: The second hole projection area (421) has a first edge (422) arranged away from the pressure relief lane projection area (31), and the second lane projection area (221) has a second edge (222) arranged away from the pressure relief lane projection area (31), and the distance between the first edge (422) and the second edge (222) is 14m to 16m.

8. The method for preventing impact by distributed horizontal hole blasting in overburden roadway of full coal mining area according to claim 7 is characterized in that: The depth of the first blasting hole (41) is 18m to 24m, and the depth of the second blasting hole (42) is 58m to 68m.

9. The method for preventing impact by distributed horizontal hole blasting in overburden roadway of full coal mining area according to claim 8, characterized in that: The charging parameters include charging amount and charging length. The charging amount of the first blasting hole (41) is 40kg-60kg, and the charging length of the first blasting hole (41) is 12m-16m. The charging amount of the second blasting hole (42) is 80kg-100kg, and the charging length of the second blasting hole (42) is 40m-44m.

10. The method for preventing impact by distributed horizontal hole blasting in overburden roadway of full coal mining area according to any one of claims 1 to 9, characterized in that: The distance between the bottom plate of the pressure relief tunnel (3) and the coal seam is 8m to 12m.

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