A blasting structure for matte surface excavation

Abstract

The present invention provides a blasting structure for sub-polished surface excavation, comprising: a groove hole, which is arranged at a predetermined position of an excavation working face; an empty hole, six of which are arranged around the groove hole to provide compensation space for the groove hole when blasting; a groove auxiliary hole, four of which are arranged around the groove hole and located at the periphery of the empty hole; a first auxiliary hole and a second auxiliary hole; two of the first auxiliary holes and two of the second auxiliary holes are arranged on the left and right sides of the excavation working face, and the two of the first auxiliary holes and two of the second auxiliary holes on the left side of the excavation working face are arranged alternately, and the two of the first auxiliary holes and two of the second auxiliary holes on the right side of the excavation working face are arranged alternately; a top hole, seven of which are arranged at the upper end of the excavation working face; a bottom hole, five of which are arranged at the lower end of the excavation working face; an auxiliary hole, a plurality of auxiliary holes are distributed at the periphery of the groove auxiliary hole.

Description

Technical Field

[0001] The invention relates to a blasting structure for sub-polished surface excavation. Background Art

[0002] Tunnels are various passages drilled between the surface and the ore body, used for ore transportation, ventilation, drainage, pedestrians, and various necessary preparatory works for the new excavation of ore for metallurgical equipment. Currently, smooth blasting and semi-smooth blasting are generally used for excavation.

[0003] Sub-smooth surface blasting is a blasting technology based on smooth surface blasting. At present, mines adopt sub-smooth surface blasting because: 1. The design cost of smooth surface blasting is high; 2. Not all mines are suitable for smooth surface blasting. According to the design requirements of some mines, the stage chamber method is backfilled immediately after mining. If the smooth surface blasting is directly used, it will be a great waste. Therefore, a sub-smooth surface blasting technology that is one level lower than the smooth surface blasting and suitable for the chamber method mining structure is designed. However, when using sub-smooth surface blasting for tunnel excavation, the current excavation distance is 2.7 meters, the excavation speed is slow, the efficiency is low, and the production progress is seriously affected. Summary of the invention

[0004] The purpose of the present invention is to overcome the above-mentioned defects. The inventors have found that if one wants to excavate 3.7 meters at one time, it is not necessary to increase the blasthole depth from 2.7m to 3.7m, and then increase the amount of explosives on the basis of the original explosive structure, so as to increase the cycle footage; if such improvements are made, the amount of floating stones on the arch and the side walls and the over-excavation and under-excavation situations will be very serious, and the support costs adopted later will be even higher; after long-term on-site research and experiments, the applicant provides a blasting structure for matte surface excavation, which can excavate 3.7 meters at one time without increasing the amount of floating stones on the arch and the side walls, and without over-excavation and under-excavation situations.

[0005] The present invention adopts the following technical solutions:

[0006] A blasting structure for sub-finished surface excavation, comprising: a groove hole, which is arranged at a predetermined position of an excavation working face; an empty hole, six of which are arranged around the groove hole to provide compensation space for the groove hole during blasting; a groove auxiliary hole, four of which are arranged around the groove hole and located at the periphery of the empty hole; a first auxiliary hole and a second auxiliary hole, two of which are arranged on the left and right sides of the excavation working face, and two of which are arranged alternately on the left side of the excavation working face and two of which are arranged alternately on the right side of the excavation working face; a top hole, seven of which are arranged at the upper end of the excavation working face; a bottom hole, five of which are arranged At the lower end of the excavation working face; auxiliary eyes, several auxiliary eyes are distributed on the periphery of the groove auxiliary eye, and are located on the inner side of the first auxiliary eye, the second auxiliary eye, the top eye, and the bottom eye; the hole direction of each of the groove eyes, empty eyes, groove auxiliary eyes, first auxiliary eyes, second auxiliary eyes, top eyes, bottom eyes, and auxiliary eyes is the same as the excavation direction; the bottom of each of the groove eyes, groove auxiliary eyes, first auxiliary eyes, second auxiliary eyes, top eyes, bottom eyes, and auxiliary eyes is provided with a detonation device; the bottom of each of the first auxiliary eye blast holes is loaded with explosives, and the rear intervals are loaded with explosives; the bottom of each of the second auxiliary eye blast holes is loaded with explosives, and the rear intervals are loaded with explosives, and the rear intervals of the first auxiliary eye and the rear intervals of the second auxiliary eye are staggered in the horizontal direction.

[0007] Preferably, the slot hole is 1.2m away from the ground, 3.7m deep, loaded with ten explosives, 3.5m long, 3.0kg of explosives, and continuously loaded with explosives; each of the empty holes has a hole depth of 3.75m and is 0.1m away from the slot hole; each of the auxiliary slot holes has a hole depth of 3.7m, loaded with ten explosives, 3.5m long, 3.0kg of explosives, and continuously loaded with explosives; each of the first auxiliary holes has a hole depth of 3.7m and is loaded with Four and a half sticks of explosives are loaded, one and a half sticks of explosives are loaded at the bottom of the hole, and half a stick of explosives is loaded at intervals at the back; each of the second-side holes has a hole depth of 3.7m and is loaded with four and a half sticks of explosives, one stick of explosives is loaded at the bottom of the hole, and half a stick of explosives is loaded at intervals at the back; each of the top holes has a hole depth of 3.7m and is loaded with five sticks of explosives, one stick of explosives is loaded at the bottom of the hole, and half a stick of explosives is loaded at intervals at the back; each of the bottom holes has a hole depth of 3.7m and is loaded with ten sticks of explosives, the length of the loaded explosives is 3.5m, the weight of the loaded explosives is 3.0kg, and the explosives are loaded continuously.

[0008] Preferably, the auxiliary eye includes a first auxiliary eye, a second auxiliary eye, a third auxiliary eye, a fourth auxiliary eye and a fifth auxiliary eye; four of the first auxiliary eyes are arranged around the groove eye and are located around the groove auxiliary eye; four of the second auxiliary eyes are arranged around the groove eye and are located around the first auxiliary eye; four of the third auxiliary eyes are arranged around the groove eye and are located around the second auxiliary eye; six of the fourth auxiliary eyes are arranged around the groove eye and are located around the third auxiliary eye; three of the fifth auxiliary eyes are located between the fourth auxiliary eye and the top eye, and the three fifth auxiliary eyes are arranged in an inverted triangle.

[0009] Preferably, each of the first auxiliary holes has a hole depth of 3.7m, is loaded with ten explosives, has a length of 3.5m, has a weight of 3.0kg, and is continuously loaded with explosives. The second auxiliary hole, the third auxiliary hole, the fourth auxiliary hole, and the fifth auxiliary hole have a hole depth of 3.7m, are loaded with eight explosives, have a length of 2.8m, have a weight of 2.4kg, and are continuously loaded with explosives.

[0010] Preferably, each of the first gang eyes has a hole depth of 3.7m, and is loaded with four and a half sticks of explosives, with the explosives loaded at intervals. The first stick of explosive is loaded at the bottom of the hole of the first gang eyes, and the other explosives are cut in the middle, and half a stick of explosive is installed close to the first stick of explosive, and then half a stick of explosive is installed every 20cm until it is fully loaded; each of the second gang eyes has a hole depth of 3.7m, and is loaded with four and a half sticks of explosives, with the explosives loaded at intervals. The first stick of explosive is loaded at the bottom of the hole of the second gang eyes, and the other explosives are cut in the middle, and half a stick of explosive is installed 20cm away from the first stick of explosive, and then half a stick of explosive is installed every 20cm until it is fully loaded.

[0011] Preferably, the detonating device is an electronic digital detonator; two electronic digital detonators are provided at the bottom of the groove hole; and an electronic digital detonator is provided at the bottom of each of the groove auxiliary hole, the first auxiliary hole, the second auxiliary hole, the top hole, the bottom hole, and the auxiliary hole.

[0012] The beneficial effects of the present invention are as follows: through the overall blasthole distribution design and the design of the odd-even interval explosive loading structure for adjacent blastholes on the same side, it is ensured that when the sub-finished surface is excavated for about 3.7 meters, the blasting energy distribution can be more uniform, the energy utilization rate can be more sufficient, the over-excavation and under-excavation of the side surface can be greatly improved, the side surface can be made smoother, and the amount of pumice stone processing can be significantly reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the present invention.

[0014] Figure 2 It is a schematic diagram of charging of the groove eye of the present invention.

[0015] Figure 3 It is a schematic diagram of charging of the auxiliary hole, the first auxiliary hole and the bottom hole of the present invention.

[0016] Figure 4 It is a schematic diagram of charging the second auxiliary eye, the third auxiliary eye, the fourth auxiliary eye and the fifth auxiliary eye of the present invention.

[0017] Figure 5 It is a schematic diagram of the charge of the first gang of eyes of the present invention.

[0018] Figure 6 It is a schematic diagram of the charge of the second gang eye of the present invention.

[0019] Figure 7 It is a schematic diagram of the charge of the top eye of the present invention. DETAILED DESCRIPTION

[0020] In order to make the purpose and technical solution of the present invention clearer, the present invention is further described below in conjunction with the accompanying drawings and embodiments:

[0021] like Figure 1 to Figure 7 A blasting structure for matte surface excavation shown in the figure comprises a groove eye A1 arranged at a predetermined position of the excavation working face (the excavation working face in this embodiment is divided into a lower rectangular face and an upper arc face, the length of the rectangular face is 3.8m, the height is 2.3m, and the height of the arc face is 1.3m), the groove eye A1 is located at the center position of the left and right sides of the excavation working face, the height is 1.2m from the ground, the hole depth is 3.7m, the hole diameter is 43mm, and ten explosives are loaded (emulsion explosives in this embodiment), the length of the explosives is 3.5m, the weight of the explosives is 3.0kg, the explosives are loaded continuously, the hole mouth is blocked with gun mud, a charging eye is provided at the bottom of the hole, the charging eye is provided with two electronic digital detonators 2, which are detonated by the electronic digital detonators.

[0022] A number of empty holes are arranged around the groove hole A1. In this embodiment, six empty holes B1, B2, B3, B4, B5, and B6 are arranged with the groove hole A1 as the center of the circle to provide compensation space for the groove hole A1 during blasting. The six empty holes have a hole depth of 3.75m, a hole diameter of 76mm, and are 0.1m away from the groove hole.

[0023] Four auxiliary groove holes C1, C2, C3, and C4 are arranged around the groove hole A1, located outside the several empty holes, forming a diamond arrangement. Each of the auxiliary groove holes has a hole depth of 3.7m and a hole diameter of 43mm. It is loaded with ten explosives, with a length of 3.5m and a mass of 3.0kg. The explosives are loaded continuously and the hole mouth is blocked with gun mud. There is a charging hole at the bottom of the hole. The charging hole is provided with an electronic digital detonator 2, which is detonated by the electronic digital detonator.

[0024] A plurality of auxiliary eyes are arranged around the groove cutting eye A1 and are located outside the four groove cutting auxiliary eyes; the auxiliary eyes in this embodiment include a first auxiliary eye, a second auxiliary eye, a third auxiliary eye, a fourth auxiliary eye, and a fifth auxiliary eye.

[0025] The four first auxiliary holes D1, D2, D3, and D4 are arranged around the groove hole A1, located outside the groove auxiliary hole, forming a rectangular arrangement; each of the first auxiliary holes has a hole depth of 3.7m and a hole diameter of 43mm, and is loaded with ten explosives, a loaded length of 3.5m, and a loaded mass of 3.0kg. The explosives are loaded continuously, and the hole mouth is blocked with gun mud. There is a charging hole at the bottom of the hole, and the charging hole is provided with an electronic digital detonator 2, which is detonated by the electronic digital detonator.

[0026] The four second auxiliary holes E1, E2, E3, and E4 are arranged around the groove hole A1, located outside the first auxiliary hole, forming a diamond arrangement; each of the second auxiliary holes has a hole depth of 3.7m and a hole diameter of 43mm, and is loaded with eighteen explosives, a length of 2.8m, and a mass of 2.4kg. The explosives are loaded continuously, and the hole mouth is blocked with gun mud. There is a charging hole at the bottom of the hole, and the charging hole is provided with an electronic digital detonator 2, which is detonated by the electronic digital detonator.

[0027] The four third auxiliary holes F1, F2, F3, and F4 are arranged around the groove hole A1, located outside the second auxiliary hole, forming a rectangular arrangement; each of the third auxiliary holes has a hole depth of 3.7m and a hole diameter of 43mm, and is loaded with eight explosives, with a length of 2.8m and a mass of 2.4kg. Explosives are loaded continuously, and the hole mouth is blocked with gun mud. There is a charging hole at the bottom of the hole, and the charging hole is provided with an electronic digital detonator, which is detonated by the electronic digital detonator.

[0028] The six fourth auxiliary holes G1, G2, G3, G4, G5, and G6 are located on both sides of the groove eye A1 and outside the third auxiliary eye to form a rectangular arrangement; each of the fourth auxiliary holes has a hole depth of 3.7m and a hole diameter of 43mm. It is loaded with eighteen explosives, with a length of 2.8m and a mass of 2.4kg. The explosives are loaded continuously and the hole mouth is blocked with gun mud. A charging hole is provided at the bottom of the hole. The charging hole is provided with an electronic digital detonator 2, which is detonated by the electronic digital detonator.

[0029] The three fifth auxiliary holes L1, L2, and L3 are located between the groove eye and the top eye, and above the second auxiliary eye, the third auxiliary eye, and the fourth auxiliary eye. The three fifth auxiliary eyes are arranged in an inverted triangle. Each of the fifth auxiliary eyes has a hole depth of 3.7m and a hole diameter of 43mm. It is loaded with eighteen explosives, a length of 2.8m, and a mass of 2.4kg. Explosives are loaded continuously, and the hole mouth is blocked with gun mud. There is a charging eye at the bottom of the hole. The charging eye is provided with an electronic digital detonator 2, which is detonated by the electronic digital detonator.

[0030] Two first helping eyes and two second helping eyes are provided on the left and right sides of the excavation working face, and the two first helping eyes and two second helping eyes on the left side of the excavation working face are arranged alternately, and the two first helping eyes and two second helping eyes on the right side of the excavation working face are arranged alternately. In this embodiment, first helping eyes H1, H3, H5, H7 and second helping eyes H0, H2, H4, H6 are provided; the right side of the excavation working face is H0, H1, H2, H3 from top to bottom; the left side of the excavation working face is H7, H6, H5, H4 from top to bottom.

[0031] Each of the first gang holes is 3.7m deep and 43mm in diameter, and is loaded with four and a half sticks of explosives 1. The explosives are loaded at intervals, with the first stick of explosives loaded at the bottom of the first gang hole, the other sticks of explosives being cut in the middle, and half a stick of explosives being installed close to the first stick of explosives (i.e., one and a half sticks of explosives are installed at the bottom of the first gang hole), and then half a stick of explosives is loaded at intervals of 20cm through a small radius PVC pipe 3 until all the explosives are loaded; the hole mouth is blocked with gun mud, and a charging hole is provided at the bottom of the hole, and the charging hole is provided with an electronic digital detonator 2, which is detonated by the electronic digital detonator.

[0032] Each of the second gang holes is 3.7m deep and 43mm in diameter. It is loaded with four and a half sticks of explosives, which are loaded at intervals. The first stick of explosive is loaded at the bottom of the second gang hole, and the other explosives are cut in the middle. Half a stick of explosive is installed 20cm away from the first stick of explosive. Then half a stick of explosive is loaded every 20cm through a small radius PVC pipe until it is fully loaded. The hole mouth is blocked with gun mud, and a charging hole is set at the bottom of the hole. The charging hole is provided with an electronic digital detonator, which is detonated by the electronic digital detonator.

[0033] Five bottom holes J1, J2, J3, J4, and J5 are arranged at the lower end of the excavation working face; each of the bottom holes has a hole depth of 3.7m and a hole diameter of 43mm. It is loaded with ten explosives, with a length of 3.5m and a weight of 3.0kg. The explosives are loaded continuously until they are finished. The hole mouth is blocked with gun mud. A charging hole is arranged at the bottom of the hole. An electronic digital detonator 2 is arranged at the charging hole. The electronic digital detonator is used for detonation. The hole mouth is blocked with gun mud. A charging hole is arranged at the bottom of the hole. An electronic digital detonator 2 is arranged at the charging hole. The electronic digital detonator is used for detonation.

[0034] Seven top holes K1, K2, K3, K4, K5, K6 and K7 are arranged at the upper end of the excavation working face; each of the top holes has a hole depth of 3.7m and a hole diameter of 43mm, and is loaded with five explosives. The first explosive is loaded at the bottom of the top hole, and the other explosives are cut in the middle, and half a stick of explosive is loaded at every 20cm through a small radius PVC pipe 3 at the rear until it is fully loaded; the hole mouth is blocked with gun mud, and a charging hole is arranged at the bottom of the hole, and the charging hole is provided with an electronic digital detonator 2, which is detonated by the electronic digital detonator.

[0035] The hole direction of each of the groove holes, empty holes, groove auxiliary holes, first group holes, second group holes, top holes, bottom holes and auxiliary holes is the same as the excavation direction.

[0036] The present invention adopts the blasting sequence from the center to the outer circle for blasting, and the auxiliary holes for groove cutting and the auxiliary holes in the middle are arranged in a square and diamond shape in a staggered manner; in this way, the blast holes can be distributed more evenly on the same plane, and the mutual support between rocks can be effectively destroyed during blasting. Moreover, the blasting is carried out step by step outward to ensure stable outward expansion, which is conducive to the formation of regular groove cutting.

[0037] Except for the first gang hole, the second gang hole and the top hole, the invention adopts hole-by-hole detonation, and the detonation order is groove hole A1, groove auxiliary holes C1, C2, C3, C4, first auxiliary holes D1, D2, D3, D4, second auxiliary holes E1, E2, E3, E4, third auxiliary holes F1, F3, F2, F4, fourth auxiliary holes G1, G2, G3, G5, G4, G6, bottom holes J3, J4, J2, J5, J1; the first gang hole and the second gang hole H0~H7 are detonated in the same section, and the top holes K1~K7 are detonated in the same section.

[0038] The matte surface excavation of the present invention is a controlled blasting technology that achieves the goal of keeping the wall surface flat and not obviously damaged after blasting by correctly selecting blasting parameters and reasonable construction methods, and performing zoned and segmented micro-difference blasting; the key points are to drill a row of blastholes with a hole spacing matching the minimum resistance line on the designed excavation contour line, and adopt an uncoupled explosive loading or an interval explosive loading structure, and after the main excavation blasting, detonate the peripheral holes, thereby forming an excavation surface with flat and regular face and tunnel surroundings.

[0039] Its advantages are: 1. The blast pile is concentrated and the block size is uniform, which is conducive to shoveling; 2. The blast hole utilization rate is high, the contour regularity is good, and the over-excavation is greatly reduced, thereby reducing the amount of slag discharge and alleviating the burden on the excavation, loading and transportation system; for the caverns supported by shotcrete, it saves the injection raw materials and speeds up the excavation speed; 3. No or very few blast cracks are generated after blasting, and the original structural cracks do not expand due to blasting, which enhances the bearing capacity of the surrounding rock itself, effectively ensures construction safety, and creates favorable conditions for rapid construction.

[0040] In the description of the invention, it should be noted that the terms "upper", "lower", "inner", "outer", "front end", "rear end", "two ends", "one end", "the other end" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0041] In the description of the invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "provided with", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0042] The components used in the present invention are all universal standard parts or components known to those skilled in the art, and their structures and principles can be known to those skilled in the art through technical manuals or conventional experimental methods.

[0043] The above description is only a preferred embodiment of the present invention and does not limit the technical scope of the present invention. Therefore, any slight modification, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention still fall within the protection scope of the present invention.

Claims

1. A blasting structure for matte surface excavation, It is characterized in that include: The slot holes are set at the predetermined positions of the excavation working face; Empty holes, six of which are arranged around the cut holes to provide compensation space for the cut holes during blasting; Grooving auxiliary eyes, four of which are arranged around the grooved eye and located at the periphery of the hollow eye; A first support eye and a second support eye; two of the first support eyes and two of the second support eyes are arranged on the left and right sides of the excavation working face, and the two of the first support eyes and the two of the second support eyes on the left side of the excavation working face are arranged alternately, and the two of the first support eyes and the two of the second support eyes on the right side of the excavation working face are arranged alternately; Top holes, seven of which are arranged at the upper end of the excavation working face; Bottom holes, five of which are arranged at the lower end of the excavation working face; Auxiliary eyes, a plurality of auxiliary eyes are distributed around the auxiliary eye of the groove, and are located inside the first auxiliary eye, the second auxiliary eye, the top eye, and the bottom eye; The hole direction of each of the cut holes, empty holes, auxiliary cut holes, first auxiliary holes, second auxiliary holes, top holes, bottom holes and auxiliary holes is the same as the excavation direction; A detonation device is provided at the bottom of each of the groove holes, groove auxiliary holes, first auxiliary holes, second auxiliary holes, top holes, bottom holes, and auxiliary holes; The bottom of each of the first gang holes is filled with explosives, and the rear is filled with explosives at intervals; The bottom of each of the second gang holes is loaded with explosives, and the rear is filled with explosives at intervals, and the position of the explosives at the rear interval of the first gang hole and the position of the explosives at the rear interval of the second gang hole are staggered in the horizontal direction; The auxiliary eyes include a first auxiliary eye, a second auxiliary eye, a third auxiliary eye, a fourth auxiliary eye, and a fifth auxiliary eye; The cutout hole is 1.2m from the ground, 3.7m deep, loaded with ten explosives, 3.5m long, 3.0kg in weight, and loaded continuously; Each of the hollow holes has a hole depth of 3.75m and is 0.1m away from the cut hole; Each of the auxiliary holes for cutting grooves has a hole depth of 3.7m, is loaded with ten explosives, has an explosive length of 3.5m, has an explosive weight of 3.0kg, and is continuously loaded with explosives; Each of the first gang holes has a depth of 3.7m and is loaded with four and a half sticks of explosives, one and a half sticks of explosives at the bottom of the hole and half sticks of explosives at the rear interval; Each of the second gang holes has a depth of 3.7m and is loaded with four and a half sticks of explosives, one stick of explosives at the bottom of the hole and half a stick of explosives at the rear interval; Each of the top holes has a depth of 3.7m and is loaded with five sticks of explosives, one stick of explosives at the bottom of the hole, and half a stick of explosives at intervals at the rear; Each of the bottom holes has a depth of 3.7m, is loaded with ten explosives, has a length of 3.5m, a weight of 3.0kg, and is loaded continuously.

2. A blasting structure for matte surface excavation according to claim 1, Features: Four of the first auxiliary eyes are arranged around the groove hole and are located at the periphery of the groove auxiliary eye; Four of the second auxiliary eyes are arranged around the groove eye and are located outside the first auxiliary eye; Four third auxiliary eyes are arranged around the cutout eye and are located outside the second auxiliary eye; Six fourth auxiliary eyes are arranged around the cutout eye and are located outside the third auxiliary eye; The three fifth auxiliary eyes are located between the fourth auxiliary eye and the top eye, and the three fifth auxiliary eyes are arranged in an inverted triangle.

3. A blasting structure for matte surface excavation according to claim 1, Features: Each of the first auxiliary holes has a hole depth of 3.7m, is loaded with ten explosives, has a length of 3.5m, has a weight of 3.0kg, and is loaded continuously; The second auxiliary eye, the third auxiliary eye, the fourth auxiliary eye and the fifth auxiliary eye have a hole depth of 3.7m, are loaded with eight explosives, have a length of 2.8m, a weight of 2.4kg, and are loaded with explosives continuously.

4. A blasting structure for matte surface excavation according to claim 1, Features: Each of the first gang holes is 3.7m deep and is loaded with four and a half sticks of explosives. The first stick of explosives is installed at the bottom of the first gang hole. The other sticks of explosives are cut in the middle and half of the stick is installed close to the first stick. After that, half a stick of explosives is installed every 20cm until all the explosives are installed. Each of the second gang holes is 3.7m deep and is loaded with four and a half sticks of explosives. The explosives are loaded at intervals. The first stick of explosive is loaded at the bottom of the second gang hole. The other sticks of explosives are cut in the middle and half a stick of explosive is installed 20cm away from the first stick of explosive. Thereafter, half a stick of explosive is loaded every 20cm until all the explosives are loaded.

5. A blasting structure for matte surface excavation according to claim 1, Features: The detonation device is an electronic digital detonator; Two electronic digital detonators are arranged at the bottom of the hole of the groove; An electronic digital detonator is arranged at the bottom of each of the auxiliary holes for cutting grooves, the first auxiliary holes, the second auxiliary holes, the top holes, the bottom holes and the auxiliary holes.

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