Blasting method for locally weakening hard rock on tunneling working face of underground coal mine by using water exploring hole

Abstract

The invention discloses a blasting method for locally weakening hard rock on an underground coal mine driving working face by using a water exploring hole, and belongs to the technical field of underground coal mine roadway driving engineering. The method comprises the following steps: identifying and confirming a constructed water exploring hole on a tunneling working face as a blasting empty hole; a plurality of blast hole sets are arranged in the circumferential direction of the empty hole with the empty hole as the center datum, and different distances are formed between the blast hole sets and the empty hole; the blast holes in the blast hole group are filled with explosives and provided with detonators, the detonating sections of the detonating sections are determined based on the distance between the detonating sections and the empty holes, and a sequential detonating mechanism from inside to outside is formed; all the detonators are connected into a detonating network in parallel for blasting, the free face is changed from small to large by means of the detonating interval time of the detonators in different sections, and hard rock weakening is finally achieved by combining the stress wave superposition effect. According to the method, the existing water exploring hole in the underground coal mine is creatively used as the blasting empty hole, and the hard rock weakening effect is remarkably improved in combination with the optimized blast hole arrangement and the segmented detonation technology.

Description

Technical Field

[0001] This invention relates to the field of coal mine underground roadway excavation engineering technology, specifically to a blasting method for locally weakening hard rock in coal mine underground excavation faces using water exploration holes. Background Technology

[0002] As coal mining extends into deeper strata, the excavation of underground roadways frequently encounters hard rock formations with compressive strength exceeding 70 MPa, posing a severe challenge to roadheader operations. While roadheaders perform well in coal roadways and medium-hard rock formations, their cutting capacity decreases significantly in hard rock formations, resulting in problems such as high consumption of cutting teeth, low excavation efficiency, and increased costs, which can easily lead to an imbalance between mining and excavation operations.

[0003] In addition, the safety principle of "exploration before excavation" is generally implemented in underground coal mines, which means that water exploration holes must be constructed before tunnel excavation to explore the hydrogeological conditions of the rock mass ahead. These water exploration holes are usually more than 30m deep and have a diameter of more than 65mm, but in traditional technology they are only used for geological exploration purposes and are not effectively used for blasting operations, resulting in a waste of engineering resources.

[0004] Currently, there are three main technical solutions for hard rock treatment: The first is to directly use the traditional drill and blast method to replace the roadheader, but this method has low mechanization, high labor intensity, and reverts to an inefficient operating mode; the second is shallow hole blasting pre-splitting technology, which involves drilling fewer blast holes than the first method, with a blast hole depth of generally 2.0-3.0m. Shallow hole pre-splitting is performed first, and then the roadheader is used for shaping, but multiple process conversions are still required; the third is deep hole blasting pre-splitting technology, with blast hole depths exceeding 25m. Although it can achieve multiple days of progress with a single pre-splitting operation, the drilling workload is large, the blasting energy utilization rate is low, the concentration of toxic and harmful gases emitted after blasting is high, and the disturbance range to the surrounding rock is large.

[0005] Therefore, existing blasting methods generally suffer from the following technical bottlenecks: dense arrangement of blast holes leads to long drilling times; high consumption of blasting materials; high concentrations of toxic gases such as CO generated by blasting, resulting in long smoke extraction times; and frequent transitions between drilling, blasting, and tunneling processes, affecting overall construction efficiency. These factors collectively restrict the rapid excavation of hard rock roadways in coal mines, urgently requiring an innovative solution that can balance blasting effectiveness with construction efficiency. Summary of the Invention

[0006] The purpose of this invention is to provide a blasting method for locally weakening hard rock in underground coal mine tunneling faces using water exploration holes. By innovatively using water exploration holes as blasting voids and optimizing the arrangement of blast holes and the detonation sequence, this method solves the problems of low operating efficiency, excessive emissions of harmful gases, and frequent multi-process conversions in existing technologies, thereby achieving efficient tunneling of hard rock roadways in underground coal mines.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A blasting method for locally weakening hard rock in underground coal mine tunneling faces using water exploration holes includes the following steps: S1. Confirm the existing water exploration holes on the tunneling face that are suitable for making blasting holes; S2. Using the hollow hole as the central reference, multiple groups of boreholes are arranged around it in the circumference. Each group of boreholes includes at least one charging borehole, and each group of boreholes is spaced at a different distance from the hollow hole. S3. Explosives are loaded into the boreholes in the borehole group and detonators are installed, wherein: the detonation segment of the detonator installed in each borehole group is determined based on its distance from the hole, so that the borehole group closer to the hole is detonated before the borehole group farther from the hole, forming a sequential detonation mechanism with a delay from the inside to the outside. S4. Connect all detonators in parallel to the detonation network, seal the blast hole after safety inspection, and carry out a single ignition blast to weaken the hard rock through the stress wave superposition effect.

[0008] Furthermore, the diameter of the water exploration hole mentioned in S1 is not less than 65mm, the depth is greater than 30m, the location is in the middle of the tunnel face, and the water exploration hole cannot be a collapsed hole.

[0009] Furthermore, the identification of the water exploration holes described in S1 involves marking the selected water exploration holes with white paint.

[0010] Furthermore, the borehole group described in S2 comprises three circumferentially symmetrically arranged levels, specifically: The first blast hole group is located on the upper and lower sides of the hole, with a distance of 150-200mm from the hole, and is equipped with a first-stage detonator; The second blast hole group is located on the left and right sides of the hole, with a distance of 250-350mm from the hole, and is equipped with a III-stage detonator. The third borehole group is located outside the second borehole group, with a distance of 400-500mm between it and the hole, and is equipped with a V-segment detonator.

[0011] Furthermore, the first group of boreholes includes two boreholes, the second group of boreholes includes two boreholes, and the third group of boreholes includes four boreholes.

[0012] Furthermore, the diameter of the blast holes described in S2 is 40mm, the depth is 3m, and all blast holes are drilled perpendicular to the tunneling face.

[0013] Furthermore, the spacing mentioned in S2 is determined based on the following: the local weakened area of ​​the tunneling face needs to be larger than the diameter of the cutting head of the subsequent tunneling equipment, and is determined according to the straight-hole slotting theory in blasting engineering and on-site engineering practice.

[0014] Furthermore, the method of loading the explosive described in S3 is continuous loading, and the explosive is a Class III coal mine permitted emulsion explosive.

[0015] Furthermore, the detonator described in S3 is a digital electronic detonator permitted for use in coal mines, with its condenser facing the borehole opening.

[0016] Furthermore, the security detection described in S4 includes: After connecting all detonators in parallel, use a detonator to detect the circuit current; If the current is abnormal, use the process of elimination to locate and replace the faulty detonator until the test is normal, and then seal the blast hole with yellow mud.

[0017] This invention provides a blasting method for locally weakening hard rock in underground coal mine tunneling faces using water exploration holes. By innovatively utilizing existing water exploration holes in the coal mine as blasting vents, combined with optimized blast hole layout and segmented initiation technology, a significant improvement in hard rock weakening effect is achieved. Compared with existing technologies, the beneficial effects of this invention are mainly reflected in the following aspects: 1. Significantly improved operational efficiency. Compared with traditional blasting methods, this invention greatly reduces the number of blast holes and significantly shortens the drilling time. By fully utilizing water exploration holes as natural voids, the free surface effect and stress concentration effect of voids are effectively utilized, resulting in a significant improvement in blasting energy utilization and achieving efficient integration of blasting and tunneling processes.

[0018] 2. Optimized Safety and Environmental Performance. The segmented initiation design of this invention allows for the phased release of blast energy, effectively controlling blast vibration and shock wave intensity, significantly reducing the concentration of toxic gases emitted, and shortening the smoke extraction time. Simultaneously, the continuous charge structure and the control of the shaped charge cavity orientation ensure the directional propagation of blast energy, reducing the disturbance range to the surrounding rock and improving the safety performance of downhole operations.

[0019] 3. Significant technical and economic advantages. By fully utilizing existing water exploration borehole resources, the additional costs of constructing dedicated boreholes are avoided. Theoretical analysis proves that the crushed and fractured zones formed after blasting lead to a favorable redistribution of rock stress, significantly reducing the cutting resistance of the roadheader. Practical experience has shown that this method can effectively reduce the consumption of cutting teeth, extend equipment service life, and demonstrate significant economic benefits.

[0020] 4. Enhanced process adaptability. This invention is applicable to longitudinal cantilever roadheaders used in most coal mines, and efficient tunneling can be achieved simply by creating a weakened zone larger than the diameter of the cutting head in hard rock areas.

[0021] In summary, this invention effectively solves the technical bottlenecks of traditional hard rock treatment methods, achieving a comprehensive improvement in efficiency and effectiveness while ensuring safety. Attached Figure Description

[0022] Figure 1 This is a front view of the borehole arrangement of the present invention; Figure 2 This is a left view of the borehole arrangement of the present invention; Figure 3 This is a top view of the borehole arrangement of the present invention; Figure 4 This is a schematic diagram of the borehole charging structure and connection detonation of the present invention; Figure 5 This is a schematic diagram of the original stress state of the rock at the tunneling face according to the present invention; Figure 6 This is a schematic diagram showing the zoning of hard rock after localized blasting according to the present invention; Figure 7 This is a schematic diagram of the rock stress state at the cavity-containing tunneling face according to the present invention. Figure 8 This is a schematic diagram of the stress state of the cavity wall according to the present invention; In the picture: 1—First blast hole, 2—Second blast hole, 3—Third blast hole, 4—Fourth blast hole, 5—Fifth blast hole, 6—Sixth blast hole, 7—Seventh blast hole, 8—Eighth blast hole, 9—Explosive, 10—Permitted digital electronic detonator for Section I coal mine, 11—Permitted digital electronic detonator for Section III coal mine, 12—Permitted digital electronic detonator for Section V coal mine, 13—Detonator lead wire, 14—Blasting main line, 15—Detonator, 16—Loess sealing section, 17—Empty hole. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0024] The core of this invention lies in providing a blasting method for locally weakening hard rock in underground coal mine tunneling faces using existing water exploration holes. This method innovatively utilizes existing underground water exploration holes as blasting vents and optimizes the arrangement of blast holes and the detonation sequence, achieving efficient and safe hard rock weakening. This method effectively solves the technical bottlenecks of traditional blasting methods, such as a large number of blast holes, low operational efficiency, large emissions of toxic and harmful gases, and frequent changes between multiple processes. The method mainly includes: identifying existing water exploration holes on the tunneling face suitable for blasting boreholes; arranging multiple borehole groups around the borehole as the central reference, each borehole group including at least one charged borehole, with different spacing between each borehole group and the borehole; loading explosives into the boreholes in the borehole groups and configuring detonators, wherein: the detonation stage of each detonator configured in each borehole group is determined based on its spacing from the borehole, so that borehole groups closer to the boreholes detonate before those farther away, forming a sequential detonation mechanism with a delay from the inside out; connecting the detonators in parallel to the detonation network, sealing the boreholes after safety testing, and implementing a single ignition blast to weaken the hard rock through the stress wave superposition effect. The following is a detailed explanation with reference to specific embodiments.

[0025] First, identify existing water-testing holes on the tunneling face suitable for blasting boreholes. Identify suitable water-testing holes on the tunneling face as blasting borehole 17. These holes should be located in the middle of the working face, with a diameter of at least 65mm (generally 65mm or 75mm), a depth greater than 30m, and be located in the center of the tunneling face. The holes must not be collapsed, ensuring the borehole walls are intact. To facilitate accurate positioning later, clearly mark the selected water-testing holes with white paint. These water-testing holes will serve as blasting borehole 17, providing initial free face and compensation space for blasted rock. This innovative application of the procedure directly reduces the time and cost of constructing dedicated boreholes, laying a solid foundation for improved efficiency in subsequent blasting operations.

[0026] Secondly, taking the hole 17 as the central reference, multiple groups of boreholes are arranged around it in a circumferential manner. Each group of boreholes includes at least one charge borehole, and each group of boreholes has a different spacing from the hole 17.

[0027] The borehole group comprises three circumferentially symmetrically arranged levels: a first borehole group, located on the upper and lower sides of the hollow hole 17, with a distance of 150-200mm from the hollow hole 17, equipped with a first-stage detonator; a second borehole group, located on the left and right sides of the hollow hole 17, with a distance of 250-350mm from the hollow hole 17, equipped with a third-stage detonator; and a third borehole group, located outside the second borehole group, with a distance of 400-500mm from the hollow hole 17, equipped with a fifth-stage detonator. The first borehole group includes two boreholes, the second borehole group includes two boreholes, and the third borehole group includes four boreholes.

[0028] like Figures 1-3 As shown, multiple borehole groups are arranged circumferentially around borehole 17 (the marked water exploration hole) as the central reference. All boreholes are drilled perpendicular to the tunneling face, with a diameter of 40mm and a depth of 3m. This embodiment uses three levels of borehole groups arranged symmetrically: First blast hole group: located on the upper and lower sides of the empty hole 17, including the first blast hole 1 and the second blast hole 2, with a distance of 150-200mm from the empty hole 17. The second group of blast holes: located on the left and right sides of the hole 17, including the third blast hole 3 and the fourth blast hole 4, with a distance of 250-350mm from the hole 17. The third group of blast holes: located outside the second group of blast holes, including the fifth blast hole 5, the sixth blast hole 6, the seventh blast hole 7 and the eighth blast hole 8, with a distance of 400-500mm between it and the empty hole 17.

[0029] The aforementioned spacing is determined based on the following: the weakened areas of the tunneling face need to be larger than the cutting head of the subsequent tunneling equipment (commonly a roadheader). Then, the hole layout and spacing in this area are determined according to the straight-hole cutting theory in blasting engineering and on-site engineering practice. This scientific hole layout method based on stress analysis significantly improves the utilization rate of blasting energy compared to traditional experience-based hole layout methods, reducing the total number of holes by approximately 60%, and drastically shortening drilling time, thus making a significant contribution to improving overall operational efficiency.

[0030] Then, explosives are loaded into the boreholes in the borehole group and detonators are installed. The detonation stage of each detonator in each borehole group is determined based on its distance from the empty hole 17, so that borehole groups closer to the empty hole 17 detonate before those farther away, forming a sequential detonation mechanism with a delay from the inside out. The detonators are permitted digital electronic detonators for coal mines, with their shaped charge facing the borehole opening.

[0031] like Figure 4As shown, Class III permissible emulsion explosive 9 for coal mines is loaded into each borehole. The loading method is continuous loading, meaning the explosive rolls are in close contact without any gaps. In the first borehole 1, two Class III permissible emulsion explosive 9 rolls with a diameter of 35mm and a length of 30mm are first loaded. Then, two Class I permissible digital electronic detonators 10 for coal mines are installed in the third Class III permissible emulsion explosive roll. The explosive roll with the detonators is then delivered into the borehole, ensuring that the shaped charge of the detonators faces the borehole opening. Explosive 9 is then loaded into the borehole until it reaches approximately 2 meters. The above steps are repeated to complete the loading of the second borehole 2. The first borehole 1 and the second borehole 2 are relatively close to the water exploration hole, and Class I permissible digital electronic detonators for coal mines are used. Because the first borehole 1 and the second borehole 2 in the tunneling face only have one free face, in order to utilize the small free face provided by the water exploration hole, the first borehole 1 and the second borehole 2 must be close to the water exploration hole and detonated first, providing a new free face for the subsequent boreholes. Repeating the previous loading process, two Class III permitted digital electronic detonators 11 are loaded into the third borehole 3 and the fourth borehole 4, and two Class V permitted digital electronic detonators 12 are loaded into the fifth to eighth boreholes 8, completing the loading of all boreholes. The detonator leads 13 are led out of all boreholes. The first borehole 1 and the second borehole 2 detonating first provide a new free face for the third borehole 3 and the fourth borehole 4. After the third borehole 3 and the fourth borehole 4 detonate, the first borehole 1 to the fourth borehole 4 form a larger free face for the blasting of the fifth to eighth boreholes 8. Therefore, as the free face increases, the spacing between boreholes can also increase.

[0032] This configuration is based on the principle that "the closer to the hole, the higher the detonation priority." The first stage detonator detonates first, using the hole to create a new free surface. Then, the third and fifth stage detonators detonate sequentially, forming a delayed sequential detonation mechanism from the inside out, achieving stress wave superposition. This sequential detonation design, through staged energy release, makes the blasting reaction more complete. It not only effectively suppresses blasting vibration and shock wave intensity but also significantly reduces the instantaneous concentration of toxic and harmful gases (such as CO). Simultaneously, it utilizes the stress wave superposition effect to accelerate smoke and dust diffusion, thereby greatly shortening the smoke extraction time. Field application has shown that downhole operation safety has been substantially improved.

[0033] Finally, all detonators are connected in parallel to the detonation network. After safety testing, the blast holes are sealed, and a single ignition blast is performed. By varying the detonation intervals of different detonator segments, the free surface gradually increases in size, ultimately weakening the hard rock through the stress wave superposition effect. All detonator leads 13 from the blast holes are connected in parallel to the blasting busbar 14. The circuit current is checked using a detonator 15. If the current is abnormal, the faulty detonator is located and replaced (with a detonator of the same segment) using a process of elimination until the test is normal. After confirmation of normality, all blast holes are sealed with loess sealing sections 16, and a single ignition blast is performed. This rigorous safety testing process ensures the reliability of the detonation network. Combined with the aforementioned technical solutions, it avoids multiple process conversions and significantly improves the overall construction efficiency of the tunneling face.

[0034] Furthermore, the feasibility and technical effectiveness of the method of the present invention can be verified through theoretical analysis.

[0035] First, the failure mechanism of the rock mass can be described by the Mohr-Coulomb criterion and its principal stress form, as shown in the following formula: (1) in: (2) In the formula and These represent the maximum principal stress and the minimum principal stress, respectively; c is the cohesion. It is the friction angle; Uniaxial compressive strength; It represents the uniaxial tensile strength.

[0036] When a roadheader operates on the tunneling face, the rock mass is under triaxial stress, such as Figure 5 As shown, σ v For vertical stress, σ h For lateral stress, σ p Let σ be the compressive stress exerted on the rock by the cutting head of the roadheader. From formula (1), it can be seen that only when σ p Rocks can only be destroyed when the value is greater than σ1.

[0037] Secondly, after localized blasting weakens the rock, it creates cavity expansion zones, crushing zones, fracture zones, and vibration zones, such as... Figure 6 As shown. Because the rock in the crushed zone almost lost its strength, the cutting head of a roadheader was used to excavate the crushed zone, creating a cavity. This resulted in stress redistribution at the working face, as shown in the image. Figure 7 As shown, the stress state at any point within the working surface can be expressed by the formula: (3) In the formula, Radial stress; It is circumferential stress; Shear stress; This refers to the vertical stress of the rock mass. R represents the horizontal stress in the rock mass; R is the radius of the excavated cavity; r is the distance from the unit cell to the center of the cavity. The angle between the unit cell and the horizontal direction.

[0038] When R=r, the cavity wall is only subjected to tangential stress. ,like Figure 8 As shown. The stress in the cavity wall changes from a triaxial stress state to a one-dimensional stress state, greatly reducing the difficulty of rock breaking. The stress calculation formula at the cavity wall is: (4) When θ = 0° When θ = 45°, When θ = 90°, Regardless of the angle, the shear stress is greater than 0. When the roadheader's cutting head acts on the cavity wall, the direction of the shear stress is consistent with the direction of the roadheader's cutting force, further reducing the difficulty of rock breaking. In addition, there are fissures around the cavity wall caused by blasting, which further reduces the difficulty of rock breaking compared to intact rock.

[0039] In summary, this invention not only effectively solves many drawbacks of traditional hard rock blasting, but also achieves a comprehensive improvement in operational efficiency, safety performance, and economic benefits through the close integration of theoretical innovation and engineering practice, providing reliable technical support for the safe and efficient excavation of hard rock roadways in coal mines.

[0040] Embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0041] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1A device that provides the functions specified in one or more boxes.

[0042] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0043] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0044] Contents not described in detail in this specification are prior art known to those skilled in the art. It is hereby indicated that the above description is intended to help those skilled in the art understand this invention, but does not limit the scope of protection of this invention. Any equivalent substitutions, modifications, improvements, or simplifications of the above descriptions that do not depart from the essential content of this invention fall within the scope of protection of this invention.

Claims

1. A blasting method for locally weakening hard rock at a coal mine underground tunneling working face using a water exploration hole, characterized in that, The method comprises the following steps: S1, confirming a constructed water exploration hole on the tunneling face as a blast empty hole suitable for blasting; S2, arranging a plurality of blast hole groups around the empty hole as a central reference in a circumferential direction, each blast hole group comprising at least one charging blast hole, and a different spacing being provided between each blast hole group and the empty hole; S3, filling explosives into the blast holes in the blast hole groups and configuring detonators, wherein: the initiation section of the detonators configured for each blast hole group is determined based on the spacing of the blast hole group from the empty hole, so that the blast hole groups closer to the empty hole are initiated before the blast hole groups farther from the empty hole, forming an inside-out delay initiation mechanism; S4, connecting the detonators in parallel into an initiation network, plugging the blast holes after safety detection, implementing a one-time ignition blasting, and achieving weakening of hard rock through stress wave superposition effect.

2. The method according to claim 1, wherein the method is characterized in that, The diameter of the water exploration hole in S1 is not less than 65 mm, the depth is greater than 30 m, the position is in the middle of the tunneling face, and the water exploration hole cannot be a collapsed hole.

3. The method according to claim 1, wherein, In S1, the water exploration hole is identified by marking the selected water exploration hole with white paint.

4. The method according to claim 1, wherein, In S2, the blast hole group comprises three levels arranged in a circumferential direction, specifically: A first blast hole group is located on the upper and lower sides of the empty hole, has a spacing of 150-200 mm from the empty hole, and is configured with an I-section detonator; A second blast hole group is located on the left and right sides of the empty hole, has a spacing of 250-350 mm from the empty hole, and is configured with a III-section detonator; A third blast hole group is located outside the second blast hole group, has a spacing of 400-500 mm from the empty hole, and is configured with a V-section detonator.

5. The method according to claim 4, wherein the method is characterized in that, The first blast hole group comprises two blast holes, the second blast hole group comprises two blast holes, and the third blast hole group comprises four blast holes.

6. The method according to claim 1, wherein, In S2, the diameter of the blast hole is 40 mm, the depth is 3 m, and all the blast holes are perpendicular to the tunneling face.

7. The method according to claim 1, wherein, In S2, the spacing is determined based on the fact that the local weakening area of the tunneling face needs to be greater than the diameter of the cutting head of the subsequent tunneling equipment, and is determined according to the straight-hole cutting theory in blasting engineering and field engineering practice.

8. The method according to claim 1, wherein the method is characterized in that, In S3, the explosives are filled in a continuous charging manner, and the explosives are three-stage coal mine permissible emulsion explosives.

9. The method according to claim 1, wherein the method is characterized in that, In S3, the detonator is a coal mine permissible digital electronic detonator, and the energy focusing cavity faces the blast hole opening.

10. The method according to claim 1, wherein the method is characterized in that, In S4, the safety detection comprises: After connecting all the detonators in parallel, the return current is detected using a blasting machine; If the current is not normal, the exclusion method is used to locate and replace the problematic detonator until the detection is normal, and the blast hole is plugged with yellow mud.

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