High-position hard roof rock stratum long-distance fan-shaped drilling plane presplitting blasting structure

Abstract

The utility model discloses a high-position hard roof rock stratum long-distance fan-shaped drilling plane presplitting blasting structure which comprises a coal seam mining area, an air return roadway and a transportation roadway, a pressure relief roadway is arranged on the upper portion of the coal seam mining area, a plurality of blasting holes are formed in the pressure relief roadway, and the blasting holes are formed in the upper portion of the coal seam mining area. A fan-shaped hole between the blast hole and the pressure relief roadway is alpha, and the fan-shaped hole is perpendicular to the blast main hole by taking the blast hole of the pressure relief roadway as a reference and is arranged towards two sides of the blast main hole in a fan-shaped manner; wherein the air return roadway and the transportation roadway are located on the two sides of the coal seam mining area correspondingly; the pressure relief roadway is arranged in the upper area of the coal seam mining area, rectangular arrangement is formed through the fan-shaped hole alpha, the drilling inclination angle beta, the blast holes and other structures, it is guaranteed that the hole ends of the blast holes are linearly aligned, stress concentration of a roof rock stratum is effectively reduced, the blasting effect is optimized, and the roof fracture risk is reduced; and the safety and efficiency of coal mining are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of coal mining, in particular to a long-distance fan-shaped drilling plane pre-splitting blasting structure for a high-position hard roof rock layer. Background Art

[0002] A hard roof has always been a major challenge in underground coal mining. Due to its thickness and high strength, the hard roof plays a key role in controlling the movement of the multiple layers of overburden above. After its failure, the rock strata are strongly disturbed, which can easily cause the roof to sink violently, crushing supports, and even triggering dynamic hazards such as large-scale roof subsidence and rock bursts. Before the roof breaks, due to its strong bearing capacity, the roof sinks little, and the resistance increase rate of the working face supports is low. However, after the roof breaks, the roof moves violently, sinks significantly, and the resistance increase rate of the supports increases significantly, greatly increasing the difficulty of controlling mine pressure.

[0003] Existing pressure relief control measures usually involve setting blasting holes in the tunnels on both sides of the working face, and achieving the purpose of pressure relief by drilling holes towards the coal seam or roof.

[0004] However, this method has some problems: first, the pressure relief effect is limited in scope and can only achieve local pressure relief, which cannot effectively cope with changes in mine pressure over a larger range; second, the pressure relief range is small, and areas that fail to effectively relieve pressure may face a higher risk of rock burst; in addition, although traditional hydraulic fracturing methods have a wide pressure relief range and long timeliness, their high cost has become the main limiting factor for their application. Utility Model Content

[0005] The utility model aims to solve at least one of the technical problems existing in the prior art.

[0006] To this end, one purpose of the present invention is to propose a long-distance fan-shaped drilling plane pre-splitting blasting structure for high-position hard roof rock strata, by setting a pressure relief tunnel in the upper area of ​​the coal seam mining area, and setting a plurality of fan-shaped blasting holes, using a 90° drilling angle and equidistantly arranged blasting holes to form a rectangular setting, ensuring that the positions of the blasting hole ends are aligned in a straight line, effectively reducing the stress concentration of the roof rock strata, optimizing the blasting effect, reducing the risk of roof fracture, and improving the safety and efficiency of coal seam mining.

[0007] To achieve the above purpose, the utility model provides the following technical solutions: a high-position hard roof rock stratum long-distance fan-shaped drilling plane pre-splitting blasting structure, including: a coal seam mining area, a return air lane, and a transportation lane.

[0008] The upper area of ​​the coal seam mining area is provided with a pressure relief tunnel, and a plurality of blasting holes are provided inside the pressure relief tunnel. The fan-shaped holes between the blasting holes and the pressure relief tunnel are αThe fan-shaped holes are based on the blasting hole of the pressure relief tunnel, are perpendicular to the main blasting hole and are arranged in a fan-shaped manner on both sides thereof;

[0009] The return air tunnel and the transport tunnel are respectively located on both sides of the coal seam mining area, and fan-shaped pre-splitting holes are arranged in a fan shape on both sides of the main blasting hole as the center, and the hole ends of the fan-shaped pre-splitting holes are aligned in a straight line.

[0010] Preferably, the hole end is arranged parallel to the coal seam mining area.

[0011] Preferably, the included angle between the vertical direction of the main blasting hole and the horizontal plane of the pressure relief tunnel is 90°.

[0012] Preferably, the drilling inclination angle of the fan-shaped pre-splitting hole is β , the number of blasting holes, the fan-shaped holes α , the drilling inclination β The end positions of the fan-shaped pre-crack holes are aligned in a straight line and the end positions of the holes are connected to form a rectangular setting.

[0013] Preferably, the plurality of blasting holes are arranged at equal intervals.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention sets a pressure relief tunnel in the upper area of ​​the coal seam mining area, sets a plurality of blasting holes in the pressure relief tunnel, and performs pre-splitting blasting by aligning the main blasting hole of the fan-shaped hole α with the fan-shaped pre-splitting hole, which can effectively reduce the impact of the hard roof rock layer on the coal mining operation; the return air tunnel and the transport tunnel are respectively located on both sides of the coal seam mining area, and all the blasting holes are arranged symmetrically in a fan shape, ensuring that the stress and cracks generated by the blasting can fully expand to both sides, making the roof rock layer softer and easier to excavate, while avoiding adverse effects on the return air tunnel and the transport tunnel, and multiple blasting holes are arranged at equal intervals, the hole ends are set parallel to the coal seam mining area, the drilling inclination angle β and the position of the fan-shaped pre-splitting hole end are aligned to form a rectangular setting, which can effectively reduce the risk of large rock blocks in the roof rock layer due to blasting, and improve mining safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic diagram of the structure of the long-distance fan-shaped drilling plane pre-splitting blasting structure of the high-position hard roof rock layer of the utility model;

[0016] Figure 2 This is a schematic structural diagram of a pressure relief tunnel in a long-distance fan-shaped drilling plane pre-splitting blasting structure for a high-level hard roof rock layer according to the present invention;

[0017] Figure 3 It is a structural schematic diagram of the pressure relief tunnel, fan-shaped pre-splitting holes and blasting main holes in the long-distance fan-shaped drilling plane pre-splitting blasting structure of the high-position hard roof rock layer of the utility model.

[0018] In the figure: 1. Coal seam mining area; 2. Return air lane; 3. Transport lane; 4. Pressure relief lane; 5. Main blasting hole; 6. Fan-shaped pre-splitting hole; 7. Blasting hole. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0020] See also Figure 1 and Figure 2 , the embodiment of the utility model provides a high-position hard roof rock layer long-distance fan-shaped drilling plane pre-splitting blasting structure, including: a coal seam mining area 1, a return air lane 2, and a transportation lane 3;

[0021] The upper area of ​​the coal seam mining area 1 is provided with a pressure relief tunnel 4, and a plurality of blasting holes 7 are provided inside the pressure relief tunnel 4. The fan-shaped holes between the blasting holes 7 and the pressure relief tunnel 4 are α The fan-shaped holes are based on the blasting hole 7 of the pressure relief tunnel 4, are perpendicular to the blasting main hole 5 and are arranged in a fan-shaped manner on both sides thereof;

[0022] The return air tunnel 2 and the transport tunnel 3 are respectively located on both sides of the coal seam mining area 1, and fan-shaped pre-splitting holes 6 are arranged in a fan shape on both sides of the main blasting hole 5 as the center, and the hole ends of the fan-shaped pre-splitting holes 6 are aligned in a straight line.

[0023] According to the above technical solution, the blasting hole 7 exerts a pre-cracking effect on the coal seam mining area 1 (i.e., the coal seam and roof rock layer in the coal seam mining area 1), thereby effectively dispersing the stress of the roof and preventing sudden collapse of the roof.

[0024] The multiple blasting holes 7 in the pressure relief tunnel 4 and the fan-shaped holes between the pressure relief tunnel 4 are α The main blasting hole 5 is located in the upper area of ​​the angle, ensuring that the blasting hole can effectively release the stress of the roof rock layer along the predetermined direction and optimize the blasting effect.

[0025] The return air tunnel 2 and the transport tunnel 3 are respectively located on both sides of the coal seam mining area 1, and with the above-mentioned blasting main hole 5 as the center, multiple fan-shaped pre-crack holes 6 are arranged in a fan shape on both sides thereof, which can effectively release the stress in the upper area of ​​the coal seam, thereby avoiding the dangers of fracture of the roof rock layer and impact ground pressure.

[0026] The ends of the fan-shaped pre-splitting holes 6 are arranged in a straight line to ensure that the blasting effect of the blasting holes 7 can act on the roof rock layer in an orderly manner, thereby further optimizing the pressure relief effect, evenly distributing the pressure relief range, and improving the safety and operating efficiency of the coal mining process.

[0027] Furthermore, a pressure relief tunnel chamber is set inside the pressure relief tunnel 4. The pressure relief tunnel chamber serves as a special space to provide an operating area for the drilling site. During the construction process, the layout of the drilling site is closely coordinated with the spatial structure of the pressure relief tunnel chamber to ensure that the blasting holes 7, the main blasting holes 5, the fan-shaped holes and the fan-shaped pre-cracking holes 6 can be accurately arranged according to the predetermined direction and angle.

[0028] Furthermore, the drilling site consists of blasting holes 7 , main blasting holes 5 , fan-shaped holes and fan-shaped pre-splitting holes 6 .

[0029] In one embodiment, specifically, the hole end is arranged parallel to the coal seam mining area 1; through such an arrangement, it is ensured that the blasting effect propagates along the direction of the coal seam, thereby enhancing the pressure relief effect, reducing the risk of local stress concentration in the roof rock layer, preventing uneven fracture of the roof rock layer, and ensuring the safety of coal mining.

[0030] In the above technical solution, this setting ensures that the blasting effect propagates along the direction of the coal seam, thereby enhancing the pressure relief effect, reducing the risk of local stress concentration in the roof rock layer, preventing uneven fracture of the roof rock layer, and ensuring the safety of coal mining.

[0031] In one embodiment, specifically, the included angle between the vertical direction of the main blasting hole 5 and the horizontal plane of the pressure relief tunnel 4 is 90°.

[0032] According to the above technical solution, the angle between the main blasting hole and the pressure relief tunnel 4 is set to 90° to ensure the uniform distribution of the blasting holes 7, which can effectively release stress and avoid excessive concentration in a certain part of the rock layer. The larger angle provides a wider pressure relief area, which helps to reduce the risk of roof rock rupture and optimize the blasting effect.

[0033] In one embodiment, the drilling inclination angle of the fan-shaped pre-splitting hole 6 is β , the number of blasting holes 7, fan-shaped holes α , drilling inclination β , the end positions of the 6 fan-shaped pre-crack holes are aligned in a straight line and the end positions of the holes are connected to form a rectangular setting.

[0034] In the above technical solution, precise control of the position and direction of the blasting hole 7 is provided, which can ensure that the blasting wave propagates along an effective path, further evenly release the stress of the roof rock layer, optimize the blasting effect and reduce damage to the coal seam mining area 1.

[0035] Furthermore, the setting parameters of blasthole 7 are adjusted to improve the blasting effect based on factors such as the actual geological conditions of the working face, mining technical requirements, blasting rock layer thickness, lithology, and coal seam mining thickness. At the same time, the drilling inclination angle β can be adjusted based on mining conditions, rock layer properties, and blasting effect to optimize the pre-splitting and pressure relief effects.

[0036] In one embodiment, multiple blasting holes 7 are arranged at equal distances, which can ensure the continuity and consistency of blasting and avoid excessive or weak local blasting effects, thereby improving the pressure relief effect, ensuring the stability of the roof rock layer, and reducing the risk of local pressure concentration.

[0037] In summary:

[0038] By setting the blasting holes 7 and combining the fan-shaped setting with the equidistant arrangement of the blasting holes 7, the stress in the coal seam mining area 1 is dispersed, and the risk of sudden collapse of the roof rock layer in the coal seam mining area 1 due to stress concentration is prevented.

[0039] Set scalloped holes α and adjust the drilling inclination β , so that the blasting effect can spread along the coal seam direction of the coal seam mining area 1, ensuring a more uniform pressure relief effect, reducing the possibility of local stress concentration, and effectively reducing the risk of roof rock stratum rupture.

[0040] By arranging a plurality of blasting holes 7 at equal intervals, the continuity and consistency of the blasting effect are ensured, thereby ensuring the stability of the roof rock layer during the entire mining process and reducing the risk of local pressure concentration.

[0041] Any portion not described in the present invention is the same as the prior art or can be implemented using the prior art. Although the embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A long-distance fan-shaped drilling plane pre-splitting blasting structure for high-position hard roof rock strata, characterized in that: include: Coal mining area (1), return air lane (2), transport lane (3); A pressure relief tunnel (4) is provided in the upper area of ​​the coal seam mining area (1), a plurality of blasting holes (7) are provided inside the pressure relief tunnel (4), and the fan-shaped holes between the blasting holes (7) and the pressure relief tunnel (4) are α The upper area of ​​the fan-shaped hole is the blasting main hole (5), and the fan-shaped hole is perpendicular to the blasting main hole (5) with the blasting hole (7) of the pressure relief tunnel (4) as a reference and is arranged in a fan-shaped manner on both sides thereof; The return air tunnel (2) and the transport tunnel (3) are respectively located on both sides of the coal seam mining area (1), and fan-shaped pre-splitting holes (6) are arranged in a fan shape toward both sides of the blasting main hole (5) with the main hole (5) as the center, and the hole ends of the fan-shaped pre-splitting holes (6) are aligned in a straight line.

2. The long-distance fan-shaped drilling and plane pre-splitting blasting structure for high-position hard roof rock strata according to claim 1 is characterized by: The hole end is arranged parallel to the coal seam mining area (1).

3. The long-distance fan-shaped drilling and plane pre-splitting blasting structure for high-position hard roof rock strata according to claim 1 is characterized by: The included angle between the vertical direction of the main blasting hole (5) and the horizontal plane of the pressure relief tunnel (4) is 90°.

4. A long-distance fan-shaped drilling plane pre-splitting blasting structure for high-position hard roof rock strata according to claim 1, characterized in that: The drilling inclination angle of the fan-shaped pre-splitting hole (6) is β , the number of the blasting holes (7), the fan-shaped holes α , the drilling inclination β The end positions of the fan-shaped pre-crack holes (6) are aligned in a straight line and the end positions of the holes are connected to form a rectangular arrangement.

5. The long-distance fan-shaped drilling and plane pre-splitting blasting structure for high-position hard roof rock strata according to claim 1 is characterized by: The plurality of blasting holes (7) are arranged at equal intervals.

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