Blasting method for one-time formation of blasting zone at the edge of hillside open-pit mine

Abstract

This invention discloses a one-time blasting method for the edge blasting zone in a hillside open-pit mine, belonging to the field of open-pit mine safety mining technology. The method includes the following steps: S1, determining the borehole diameter and borehole mesh parameters based on the lithology of the ore; S2, dividing the edge blasting zone into an open-pit area and a main production area according to the distance between the boreholes and the free face; S3, drilling boreholes in the open-pit area and the main production area according to the determined borehole diameter and borehole mesh parameters; S4, filling the drilled boreholes with explosives; S5, connecting the filled boreholes, with the detonation sequence of the boreholes in the main production area preceding that in the open-pit area; S6, completing the detonation operation after the blasting zone is secured. This invention reduces the impact of blasting debris on normal production activities in the mine's open-pit area, reduces the workload of secondary crushing of mine partition walls and debris protection, and improves the production efficiency and economic benefits of open-pit mines.

Description

Technical Field

[0001] This invention relates to a blasting method for one-time formation of the blasting zone at the edge of a hillside open-pit mine, belonging to the field of open-pit mine safety mining technology. Background Technology

[0002] In the bench-type mining process of open-pit mines, the ore and rock need to be divided into several horizontal layers of a certain thickness, and then mined layer by layer from top to bottom in a stepped manner. For hard rock open-pit mines, rock drilling and blasting is the simplest, most economical, and most efficient method of ore and rock breaking, and it has become the main method of ore and rock breaking in large and medium-sized open-pit mines both domestically and internationally. However, the mining process of slope-type open-pit mines inevitably requires blasting operations in the open face area of ​​the mine, which has a complex environment. Such areas are usually located at the edge of the current horizontal layer, adjacent to steep slopes, and below may be existing transportation lines, gullies, residential areas, and other objects to be protected. If controlled blasting methods are not used, the flying rocks and boulders generated by the explosion can easily damage the objects to be protected, resulting in unnecessary civil or criminal disputes.

[0003] Currently, the main methods for controlling blasting debris in the edge blasting zone of hillside open-pit mines are reserving a partition wall for secondary crushing and deploying active protection devices to control blasting debris.

[0004] For example, the Chinese patent application number CN201710370213.7 discloses a method for controlled blasting and slope cutting in shallow-hole steps in complex environments; the Chinese patent application number CN201310690879.2 discloses a method for controlled blasting to loosen steep mountains near existing railway lines; and the Chinese patent application number CN201711248286.6 discloses a method for constructing high slopes more than 100m away from passageways. All of these are blasting methods that use a reserved partition wall for secondary crushing. Typically, the blasting area is divided into a large main mining area and a small adjacent slope mining area in a step-by-step blasting method. After the main mining area is blasted and the rock is broken, small-diameter blast holes or hydraulic breakers are used to mine the adjacent slope area.

[0005] For example, Chinese Patent Application No. CN202223327337.2 discloses a support structure and a protective fence for open-pit blasting rockfalls; Chinese Patent Application No. CN201711345674.5 discloses an engineering blasting slope monitoring and protection system; Chinese Patent Application No. CN202121737201.1 discloses a blasting protection device for adjacent slopes; and Chinese Patent Application No. CN202211619263.1 discloses a combined open-pit blasting rockfall protection fence and installation method. All of these technologies use active protection devices to control blasting rocks. These technologies typically involve arranging rockfall interception devices on the slope using anchor bolts, nails, and other facilities, and setting up protective fences with support capacity below the rocks, thereby achieving passive protection against blasting rocks.

[0006] The existing blasting methods mentioned above have a certain ability to prevent blasting rocks from injuring people and property when blasting in the edge blasting area of ​​open-pit mines on slopes. However, secondary crushing of the partition wall requires multiple blasting steps, which is complicated to control. The secondary blasting construction is also quite dangerous. The installation of protective fences will increase the blasting cost. All of these have brought many inconveniences to mine production and operation. New technical methods are needed to effectively protect against blasting rocks generated by blasting in the open face area of ​​open-pit mines while being easy to operate. Summary of the Invention

[0007] The technical problem solved by this invention is to provide a one-time blasting method for the edge blasting zone of a hillside open-pit mine, addressing the numerous problems existing in the current blasting methods for preventing rockfalls from blasting the open face area of ​​an open-pit mine.

[0008] This invention is achieved using the following technical solution:

[0009] A blasting method for one-time formation of the blasting zone at the edge of a hillside open-pit mine includes the following steps:

[0010] S1. Obtain the lithology of the ore and rock in the adjacent blasting zone to provide a basis for the selection of subsequent blasting parameters, and determine the borehole diameter and borehole mesh parameters based on the ore and rock lithology;

[0011] S2. Based on the distance between the blast hole and the free face, the blasting zone is divided into the free face area and the main production area. The area closer to the free face is designated as the free face area, and the remaining area farther away from the free face is designated as the main production area.

[0012] S3. Drill boreholes in the blasting zone near the edge according to the borehole diameter and borehole mesh parameters determined in step S1. The boreholes in the main production area are arranged in a vertical drilling pattern, and the row of boreholes closest to the free face in the free face area is arranged in an inclined drilling pattern, with the inclination direction being the same as the slope of the free face.

[0013] S4. The drilled blast holes are filled with explosives. The blast holes in the main production area are filled with explosives in a continuous coupled charging method, while the blast holes in the free face area are filled with explosives in a radially continuous uncoupled charging method. Furthermore, the amount of explosives in the blast holes in the free face area is gradually reduced from far to near according to the distance between the blast hole and the free face, and the length of the blast hole blocking section is increased.

[0014] S5. Connect the boreholes after the explosive charge has been filled. The detonation sequence of the boreholes in the main production area is higher than that of the boreholes in the free face area.

[0015] S6. Detonation operation completed after blast zone alert.

[0016] In the blasting method for one-time forming of the blasting zone at the edge of a hillside open-pit mine according to the present invention, further, in step S1, the main lithology and structural characteristics of the blasting zone are obtained by conducting a geological survey of the blasting zone, a two-dimensional or three-dimensional numerical calculation model of the rock mass in the blasting zone is established using the finite element software LS-DYNA, the rock mass in the blasting zone is simulated using the materials provided by the LS-DYNA software, high-energy explosive materials are selected to simulate the on-site explosives, and the actual borehole diameter and borehole mesh parameters are selected by analyzing the crack development and stress distribution of the rock mass in the blasting zone.

[0017] In the blasting method for one-time forming of the blasting zone at the edge of a hillside open-pit mine according to the present invention, the free face area is further defined as the area where the two rows of blast holes are located near the free face.

[0018] In the blasting method for one-time forming of the blasting zone at the edge of a hillside open-pit mine according to the present invention, the diameter of the blast holes in the free face area is further less than or equal to the diameter of the blast holes in the main production area. The blast holes in the free face area are selected with a smaller diameter than those in the main production area. By drilling more holes and using less explosive, effective rock breaking is achieved, secondary breaking is reduced, and flyrock and loose rock falling from the free face area are minimized.

[0019] In the blasting method for one-time forming of the edge blasting zone in a hillside open-pit mine of the present invention, further, the distance from the edge row of blast holes closest to the edge surface to the resistance line of the edge surface is 1.2-1.5 times the distance from the resistance line of the previous row of blast holes, so as to prevent excessive rolling of loose rocks during blasting of the edge surface.

[0020] In the blasting method for one-time forming of the blasting zone at the edge of a hillside open-pit mine according to the present invention, further, in step S3, different colors are used to distinguish and mark the blast holes drilled in the free face area and the main production area.

[0021] In the blasting method for one-time forming of the edge blasting zone in a hillside open-pit mine of the present invention, further, in step S3, after all blast holes are drilled, the three-dimensional geographic coordinates of each blast hole opening are recorded using an RTK device, and a blasting network diagram of the edge blasting zone is designed based on the three-dimensional geographic coordinates of each blast hole. The detonation time of each blast hole, as well as the isochron of the blasting network and the direction of rock throwing, are calculated and analyzed using blasting design software.

[0022] In the blasting method for one-time forming of the blasting zone at the edge of a hillside open-pit mine of the present invention, further, in step S4, the blast holes in the main production area are filled with ammonium nitrate explosive, and the blast holes in the free face area are filled with strip-shaped emulsion explosive, and the amount of explosive in the blast holes in the free face area is 1 / 2 to 2 / 3 of the amount of explosive in the blast holes in the main production area.

[0023] In the blasting method for one-time formation of the edge blasting zone in a hillside open-pit mine of the present invention, the side row blast holes closest to the free face area are filled with explosives in an axially spaced manner, the middle of the blast holes is blocked with rock debris, and two high-precision in-hole detonating cord detonators with different delay times are used for detonation, with the lower charge of the blast hole detonating before the upper charge.

[0024] In the blasting method for one-time formation of the blasting zone at the edge of a hillside open-pit mine according to the present invention, further, in step S5, the main production area and the free face area, and the rows of blast holes within the free face area are connected by double to multiple detonating cord detonators, so that when the blast holes in the free face area are detonated, the blast holes in the main production area in front of it have already detonated, and the broken rock blocks in the main production area have moved a certain distance toward the detonation point, thereby providing more loose holes for the blasting of the blast holes in the free face area.

[0025] In the blasting method described above in this invention, by optimizing the borehole inclination angle, borehole charge amount, charge structure, and blasting network in the free face area of ​​a hillside open-pit mine, backlash management and instantaneous free surface control are achieved during borehole blasting in the main production area. This effectively prevents rockfall in the free face area of ​​the blast zone, ensuring that the ore and rock in the free face area are broken but not immobile, forming a fractured layer that can be effectively scooped by loading equipment without the formation of blasting rocks. The main rock blocks in the edge blasting area are not thrown towards the free face, and the blasting network does not use the free face as the backlash zone. During the blasting process, the instantaneous free surface of the blasting network gradually expands with the detonation process. On the one hand, this avoids the formation of blasting rocks, effectively ensuring the normal operation of public facilities near the free face. On the other hand, it achieves one-time formation of the main production area and the free face area, avoiding secondary crushing of the partition wall and the layout of blasting rock protection facilities.

[0026] In summary, the blasting method for one-time forming of the blasting zone at the edge of a hillside open-pit mine provided by this invention effectively combines the technical advantages of post-blasting impact control, interval charging technology, and micro-delay blasting technology. It reduces the impact of blasting rocks on normal production activities in the open face area of ​​the mine, reduces the workload of secondary crushing of the mine's partition walls and rockfall protection, improves the production efficiency and economic benefits of open-pit mines, and provides strong support for safe and efficient mining in hillside open-pit mines. It has broad application value.

[0027] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the steps of the blasting method for one-time forming of the blasting zone at the edge of a hillside open-pit mine according to the present invention.

[0029] Figure 2 The above is a geographical location map of the blasting area near the edge of a hillside open-pit mine, as shown in the example.

[0030] Figure 3 This is a cross-sectional view of the blast hole layout in the edge blasting zone of a hillside open-pit mine, as shown in the example.

[0031] Figure 4 This is a schematic diagram of the blast hole structure in the edge blasting zone of a hillside open-pit mine, as shown in the embodiment.

[0032] Figure 5 This is a diagram showing the connection of blast holes in the blasting zone near the edge of a hillside open-pit mine, as illustrated in the example.

[0033] The diagram is labeled as follows: 1. Blast zone near the edge; 1-1. Main production area; 1-2. Free face area; 2. Free face slope; 3. Transport road; 4. Blast hole; 5. Distance from the bottom of the blast hole in the free face area to the last row of blast holes; 6. Distance from the bottom of the last row of blast holes in the free face area to the chassis resistance line of the free face; 7 / 9 / 11 / 13 / 15. Drill cuttings; 8. Ammonium nitrate fuel oil (ANFO); 10 / 12 / 14 / 16. Emulsion explosive; 17 / 18. High-precision detonating cord detonator; 19. Activation needle. Detailed Implementation Example

[0034] See Figure 2-5 The environment of the blasting zone in the hillside open-pit mine mentioned in this embodiment is complex. The main transportation road 3 of the mine is located below the free slope 2 on one side of the blasting zone 1. Some loose gravel is piled up on the free slope of the blasting zone. It is necessary to control the blasting rocks generated during the blasting of the blasting zone to avoid affecting the main transportation road of the mine.

[0035] For the one-step molding blasting method of this invention applied to the edge blasting area of ​​this hillside open-pit mine, such as... Figure 1 As shown, the specific steps are as follows:

[0036] S1. Obtain the lithology of the ore and rock within the blasting zone, and determine the borehole diameter and borehole network parameters based on the ore and rock lithology. A geological survey was conducted on the blasting zone of a hillside open-pit mine, and analysis revealed that the main lithology of this blasting zone is granodiorite, with relatively well-developed joints and fissures.

[0037] S2. Based on the distance between the blast hole and the free face, the blasting zone is divided into the free face area and the main production area. The area closer to the free face is designated as the free face area, and the remaining area farther away from the free face is designated as the main production area.

[0038] Considering the 10m high bench height and approximately 80-degree angle of the free face in the edge-blasting zone of a hillside open-pit mine, this embodiment defines the area within 16m of the free face (containing two rows of blast holes) of edge-blasting zone 1 as free face area 1-2, and the remaining area of ​​edge-blasting zone 1 far from the free face as main production area 1-1. Figure 2 and Figure 3 As shown.

[0039] Based on the main lithology and joint / fracture development of the area, and referring to the borehole diameters and borehole network parameters of similar lithology areas in other mines, the borehole network parameters for the main production area are determined. Specifically, the borehole diameters and network parameters for the main production area can be determined through engineering analogies to production parameters of similar mines, on-site experimental blasting studies, and reviewing relevant data on open-pit deep-hole bench blasting design. Considering the main lithology and joint / fracture development of the area, and taking into account construction convenience, the same borehole diameters and network parameters as those for the main production area can be selected. Where construction conditions permit, smaller borehole diameters can be used for the free face area compared to the main production area. By drilling more holes and using less explosive, effective rock fragmentation can be achieved, secondary fragmentation can be reduced, and flyrock and loose rock falling from the free face area can be minimized.

[0040] In this embodiment, to precisely control the blasting effect in the free face area, when initially selecting blasting parameters for the free face area, a two-dimensional or three-dimensional numerical calculation model of the rock mass in the free face area can be established using the finite element software LS-DYNA. High-energy explosive materials are used to simulate the on-site explosives, and LS-DYNA's built-in material No. 272 ​​is used to simulate the engineering rock mass. By analyzing the crack development and stress distribution of the rock mass in the free face area, reasonable blasting parameters are selected.

[0041] S3. Drill boreholes in the blasting zone near the edge according to the borehole diameter and borehole grid parameters determined in step S1. The boreholes in the main production area are arranged in a vertical drilling pattern, while the row of boreholes closest to the free face in the free face area is arranged in an inclined drilling pattern, with the inclination direction being the same as the slope of the free face.

[0042] After referring to the production blasting experience of other non-free face areas of the mine in step S2, the blasting parameters of the main production area 1-1 in this embodiment are determined as follows: the diameter of the blast hole 4 in the main production area is selected as 140mm, the ultra-deep is selected as 1m, the blast hole depth is 11m, and the hole mesh parameters are 6m×5m.

[0043] Within the free face area, the distance from the outermost row of blast holes closest to the free face to the free face's chassis resistance line is 1.2-1.5 times the distance from the chassis resistance line of the preceding row of blast holes, to prevent excessive rolling of turquoise during blasting at the free face.

[0044] In this embodiment, considering the need for construction convenience, the diameter of the blast holes 4 in the blasting zone's free face area is also selected as 140mm. In practical applications, if a multi-diameter drilling rig is available, the diameter of the blast holes in the blasting zone's free face area can be selected to be smaller than the diameter of the blast holes in the main production area, depending on the actual conditions. The last row of blast holes in the free face area is 6m from the top of the slope, with a blast hole depth of 11m and an inclination angle of 85°. The distance 6 from the bottom of the last row of blast holes in the free face area to the base resistance line of the free face is 7m. The second row of blast holes in the free face area is 10m from the top of the slope, with a blast hole depth of 11m and an inclination angle of 90°. The distance 5 from the bottom of the blast holes in the free face area to the last row of blast holes is 5m, and the distance from the last row of holes in the main production area is 5m. Figure 3 As shown.

[0045] Drilling rigs are dispatched to drill blast holes according to the layout of the blast holes in the adjacent blasting zone. During the drilling process, the drilling rig needs to drill accurately according to the blast hole position and angle. After drilling is completed, an inclinometer is used to obtain the blast hole deviation to avoid serious discrepancies between the chassis resistance line and the blasting design. After drilling is completed, RTK equipment is used to record the three-dimensional geological coordinates of each blast hole.

[0046] After all blast holes in the blasting area were completed, different colors were used to distinguish and mark the blast holes drilled in the free face area and the main production area. Specifically, blue plastic bags were used to mark the blast holes in the main production area, and red plastic bags were used to mark the blast holes in the free face area. Stones were placed on the plastic bags marking the blast holes to prevent them from moving.

[0047] S4. The drilled blast holes are filled with explosives. The blast holes in the main production area are filled with explosives using a continuous coupled charging method, while the blast holes in the free face area are filled with explosives using a radial continuous uncoupled charging method. Furthermore, the amount of explosives in the blast holes in the free face area is gradually reduced from far to near according to the distance between the blast hole and the free face, and the length of the blast hole blocking section is increased.

[0048] Specifically, such as Figure 4As shown, for the borehole filling in the main production area of ​​this embodiment, blasting engineers assign blasters to prepare an initiating charge consisting of 15 high-precision in-hole detonating cord detonators with a delay time of 350ms and 90mm diameter emulsion explosive. One initiating charge is required for each borehole in the main production area. Subsequently, the initiating charge is hoisted into the borehole using a rope, and ammonium nitrate fuel oil (ANFO) 8 is added above it until the charging height reaches 7.0m. Finally, the blasters use shovels to fill the borehole plugging section with drill cuttings (7) formed during drilling until the plugging section is level with the ground surface.

[0049] For the loading and packing of explosives in the free face area in this embodiment, the blasting engineers assign blasters to prepare initiating explosive packages made of 15-segment in-hole high-precision detonating cord detonators with a delay time of 350ms and 90mm diameter emulsion explosives, and 16-segment in-hole high-precision detonating cord detonators with a delay time of 375ms and 90mm diameter emulsion explosives. Each blast hole in the free face area requires two initiating explosive packages, one containing the 15-segment in-hole detonating cord detonator and the other containing the 16-segment in-hole detonating cord detonator.

[0050] For the remaining second row of boreholes in the free face area, firstly, a detonating charge containing a 350ms in-hole detonating cord detonator is hoisted into the borehole, and 90ms diameter emulsion explosive 12 is loaded on top until the charge height reaches 3.0m. Then, the blaster uses a shovel to load drill cuttings 11 into the plugging section until the top of the plug is 5.0m above the borehole opening. Next, another detonating charge containing a 375ms in-hole detonating cord detonator is loaded, along with 90mm diameter emulsion explosive 10 until the charge height reaches 8.0m, and drill cuttings 9 are loaded on top until level with the borehole opening. The charge amount for boreholes in the free face area is generally 1 / 2 to 2 / 3 of the charge amount for boreholes in the main production area.

[0051] For the last row of boreholes closest to the free face in the free face area, firstly, a detonating charge containing a 350ms in-hole detonating cord detonator is hoisted into the borehole. Then, 90ms diameter emulsion explosive 16 is loaded above it until the charge height reaches 3.0m. Next, the blaster uses a shovel to load drill cuttings 15 into the plugging section until the top of the plug is 6.0m above the borehole opening. Afterward, another detonating charge containing a 375ms in-hole detonating cord detonator is loaded, along with 90mm diameter emulsion explosive 14 until the charge height reaches 8.0m. Drill cuttings 13 are then loaded above it until level with the borehole opening.

[0052] S5. Connect the boreholes after the explosive charge has been filled. The detonation sequence of the boreholes in the main production area is higher than that of the boreholes in the free face area.

[0053] Importing previously recorded blast hole GPS data into blasting design software such as 3DMINE, DATAMINE, and DIGITALMINE, and based on the principles that the initiation network should not use the free face as the backlash zone, the blasting area should not use the free face as the main free face, and the instantaneous free face of the blasting area should be gradually expanded, initiation points were selected in appropriate areas of the blasting zone near the edge. A preliminary blasting network design was then performed in the blasting design software. After completing the preliminary design, the blasting network was explored and optimized using the blasting design software's built-in blasting isochron analysis and rock block throwing direction analysis functions. For the blasting area in this embodiment, after analyzing the throwing direction of broken rock blocks at different locations using 3DMINE intelligent mining software, the final initiation point was set at the right front of the blasting area.

[0054] like Figure 5 As shown, in this embodiment, the connection starts from the last row of blast holes in the free face area furthest from the detonation point. High-precision detonating cord detonators 18 with a delay time of 42ms are used for the connection between holes, and high-precision detonating cord detonators 17 with a delay time of 65ms are used for the connection between rows. In the blast holes of the main production area, a single high-precision detonating cord detonator 17 with a delay time of 65ms is used to connect different rows of blast holes. In the blast holes of the free face area, two high-precision detonating cord detonators 17 with a delay time of 65ms are connected in series to achieve detonation transmission between different rows of detonators. This ensures that the blast holes in the free face area detonate 130ms later than those in the main production area. This means that when the blast holes in the free face area detonate, the blast holes in the main production area ahead of them have already detonated, and the broken rock fragments have moved a certain distance towards the detonation point, thus providing more loosened space between the blast holes in the free face area.

[0055] S6. Detonation operation completed after blast zone alert.

[0056] After completing the security work at major intersections near the blasting area, issuing warning signals and detonation signals, and using the 19-type detonator as the detonating cord detonator to complete the blasting operation, experienced blasting engineers will check for misfires in the blasting area after the blast holes have cleared and the blast pile has stabilized. If there is no safety risk, an all-clear signal will be issued to lift the blasting area security.

[0057] Upon inspection, it was found that the slope of the exposed face in the blasting zone of this embodiment showed obvious cracks after blasting, but the slope as a whole remained intact without significant collapse. In addition, there was no significant addition of gravel on the main transport road below the exposed face slope, indicating that the blasting effect was good and the blasting operation in the blasting zone did not have a significant impact on the normal production of the mine.

[0058] In this document, the terms "upper," "lower," "front," "back," "left," "right," "top," "bottom," "inner," "outer," "vertical," and "horizontal," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only used for the clarity of expressing the technical solution and for the convenience of description, and therefore should not be construed as limiting the present invention.

[0059] In this document, the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, which includes not only the elements listed but also other elements not expressly listed.

[0060] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A blasting method for one-time formation of the blasting zone at the edge of a hillside open-pit mine, characterized in that... Includes the following steps: S1. Obtain the lithology of the ore and rock in the blasting zone, and determine the borehole diameter and borehole mesh parameters based on the ore and rock lithology; S2. Based on the distance between the blast hole and the free face, the blasting zone is divided into the free face area and the main production area. The area closer to the free face is designated as the free face area, and the remaining area farther away from the free face is designated as the main production area. S3. Drill boreholes in the blasting zone near the edge according to the borehole diameter and borehole mesh parameters determined in step S1. The boreholes in the main production area are arranged in a vertical drilling pattern, and the row of boreholes closest to the free face in the free face area is arranged in an inclined drilling pattern, with the inclination direction being the same as the slope of the free face. S4. The drilled blast holes are filled with explosives. The blast holes in the main production area are filled with explosives in a continuous coupled charging method, while the blast holes in the free face area are filled with explosives in a radially continuous uncoupled charging method. Furthermore, the amount of explosives in the blast holes in the free face area is gradually reduced from far to near according to the distance between the blast hole and the free face, and the length of the blast hole blocking section is increased. The main production area is filled with ammonium nitrate explosives in the boreholes, and the free face area is filled with strip-shaped emulsion explosives in the boreholes. The amount of explosives in the boreholes in the free face area is 1 / 2 to 2 / 3 of the amount of explosives in the boreholes in the main production area. The side-row blast holes closest to the free face in the free face area are filled with explosives in an axially spaced manner. The middle of the blast hole is blocked with rock debris. Two high-precision in-hole detonating cord detonators with different delay times are used for detonation. The lower charge of the blast hole detonates before the upper charge. Each blast hole in the free face area requires two detonation packages. For the last row of blast holes closest to the free face in the free face area, firstly, a detonating charge containing a 350ms in-hole detonating cord detonator is hoisted into the blast hole. Then, 90ms diameter emulsion explosive is filled on top of it until the charge height is 3.0m. After that, the blaster uses a shovel to fill the plugging section with drill cuttings until the top of the plug is 6.0m above the blast hole opening. Then, another detonating charge containing a 375ms in-hole detonating cord detonator is installed, and 90mm diameter emulsion explosive is filled on top until the charge height is 8.0m. Drill cuttings are then filled on top of it until it is level with the blast hole opening. For the remaining second row of boreholes in the air-facing area, firstly, a detonating charge containing a 350ms in-hole detonating cord detonator is hoisted into the borehole. Then, 90ms diameter emulsion explosive is loaded on top of it until the charge height is 3.0m. Afterward, the blaster uses a shovel to load drill cuttings into the plugging section until the top of the plug is 5.0m above the borehole opening. Then, another detonating charge containing a 375ms in-hole detonating cord detonator is loaded, and 90mm diameter emulsion explosive is loaded until the charge height is 8.0m. Drill cuttings are then loaded on top of it until it is level with the borehole opening. S5. Connect the boreholes after the explosive charge has been filled. The detonation sequence of the boreholes in the main production area is higher than that of the boreholes in the free face area. S6. Detonation operation completed after blast zone alert.

2. The blasting method for one-time formation of the blasting zone at the edge of a hillside open-pit mine according to claim 1, characterized in that: In step S1, the lithology and structural characteristics of the blasting area are obtained by conducting a geological survey of the blasting area. A two-dimensional or three-dimensional numerical calculation model of the rock mass in the blasting area is established using the finite element software LS-DYNA. The rock mass in the blasting area is simulated using the materials provided by the LS-DYNA software. High-energy explosive materials are selected to simulate the on-site explosives. The actual borehole diameter and borehole mesh parameters are selected by analyzing the crack development and stress distribution of the rock mass in the blasting area.

3. The blasting method for one-time formation of the blasting zone at the edge of a hillside open-pit mine according to claim 1, characterized in that: The free face area refers to the area where the two rows of gun holes are located near the free face.

4. The blasting method for one-time formation of the blasting zone at the edge of a hillside open-pit mine according to claim 3, characterized in that: The diameter of the boreholes in the free-face area is less than or equal to the diameter of the boreholes in the main production area.

5. The blasting method for one-time formation of the blasting zone at the edge of a hillside open-pit mine according to claim 4, characterized in that: The distance from the side row of blast holes closest to the air-free surface to the air-free surface chassis resistance line within the air-free surface area is 1.2-1.5 times the distance from the chassis resistance line of the previous row of blast holes.

6. The blasting method for one-time formation of the blasting zone at the edge of a hillside open-pit mine according to claim 1, characterized in that: In step S3, different colors are used to distinguish and mark the drilled blast holes in the free face area and the main production area.

7. The blasting method for one-time formation of the blasting zone at the edge of a hillside open-pit mine according to claim 6, characterized in that: In step S3, after all the boreholes are drilled, the three-dimensional geographic coordinates of each borehole opening are recorded using an RTK device. Based on the three-dimensional geographic coordinates of each borehole, a blasting network diagram of the adjacent blasting zone is designed. The detonation time of each borehole, as well as the isochron of the blasting network and the direction of rock throwing, are calculated and analyzed using blasting design software.

8. The blasting method for one-time formation of the blasting zone at the edge of a hillside open-pit mine according to claim 1, characterized in that: In step S5, the main production area and the air-to-ground area, as well as the rows of blast holes within the air-to-ground area, are connected by double to multiple detonating cord detonators.

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