A blasting method for a downhole right-angle roadway

Abstract

The application discloses a blasting method for a right-angle roadway in a mine, which comprises the following steps: 1) setting a deep hole in a cutting roadway of the right-angle roadway and setting a deep hole in a drift of the right-angle roadway; 2) setting a vertical deep hole in the drift in a crossing range of the cutting roadway and the drift; the vertical deep hole is located on a side of a center line of the drift away from the cutting roadway, a plurality of rows of the vertical deep holes are arranged along the center line of the drift; each row of the vertical deep holes is formed by a plurality of the deep holes arranged in a fan type, a first hole of the vertical deep holes is closest to the cutting roadway, an edge hole of the vertical deep holes is farthest away from the cutting roadway, and a row surface of each row of the vertical deep holes is perpendicular to the center line of the drift; and 3) the deep holes in the cutting roadway are exploded except for a last row of the deep holes in the cutting roadway close to the drift; then the last row of the deep holes in the cutting roadway and the vertical deep holes are exploded by using an inter-row micro-difference detonation mode; and finally, the deep holes in the drift are exploded. The method improves ore recovery.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of mine exploitation, in particular to a blasting method for a straight-angle roadway in a mine. BACKGROUND

[0002] In the process of underground mining, cutting wells or cutting lanes provide blasting compensation space for the access, the top of the cutting lane (lane) and the access converge, generally in the shape of a "T"; but the outermost access and the cutting lane (lane) are in the shape of a "straight angle". When the cutting lane (lane) normally advances to the range of the outermost access, the outermost access often has more large blocks after blasting, and even has a blasting roof accident, which greatly reduces the ore recovery of the access and increases the subsequent processing work. The reason is mainly that the rock drilling equipment can only normally drill in the center line of the access near the cutting lane (lane) due to the design of the equipment and the medium-length hole, and cannot meet the equipment operation on the side of the access roadway, so that there is only a medium-length hole in the position of the center line away from the cutting lane (lane), and there is no medium-length hole on the other side, which finally affects the insufficient compensation space of the front row of medium-length holes in the access, and finally causes various blasting problems. SUMMARY

[0003] The technical problem to be solved by the present application is to provide a blasting method for a straight-angle roadway in a mine to provide sufficient compensation space.

[0004] To solve the above technical problems, the technical scheme adopted by the present application is: 1) setting a cutting lane medium-length hole in the cutting lane of the straight-angle roadway and setting an access medium-length hole in the access of the straight-angle roadway;

[0005] 2) setting a vertical access medium-length hole in the intersection range of the cutting lane and the access; the vertical access medium-length hole is located on the side of the access center line away from the cutting lane, and a plurality of rows are arranged along the access center line; each row of vertical access medium-length holes is arranged in a fan shape by a plurality of medium-length holes, the vertical access medium-length hole closest to the cutting lane is a vertical access medium-length hole No. 1, and the vertical access medium-length hole farthest from the cutting lane is a vertical access medium-length hole edge hole, and the row surface of each row of vertical access medium-length holes is perpendicular to the access center line;

[0006] 3) the cutting lane medium-length hole is exploded except the last row of cutting lane medium-length holes close to the access; then the last row of cutting lane medium-length holes and the vertical access medium-length hole are exploded by row-to-row micro-difference detonation; and finally the access medium-length hole is exploded.

[0007] Further, in step 2), the included angle between each row of vertical access medium-length hole No. 1 and the ground of the straight-angle roadway is 90°, and the included angle between the vertical access medium-length hole edge hole and the ground of the straight-angle roadway is 52°.

[0008] Further, in the step 2), the distance from the bottom of the holes in each row of vertical access deep holes is 1.8-2m.

[0009] Further, in the step 2), the distance from the bottom of the holes in each row of vertical access deep holes is 1.8-2m.

[0010] Further, in the step 2), the distance from the bottom of the holes in each row of vertical access deep holes is 1.8-2m.

[0011] Further, in the step 2), the distance from the bottom of the holes in each row of vertical access deep holes is 1.8-2m.

[0012] The beneficial effects produced by the above technical solution are that the application adopts the two kinds of deep hole arrangement modes of the deep holes in the cutting lane and the deep holes in the vertical access in the position of the right-angle roadway, the last row of deep holes in the cutting lane and the deep holes in the vertical access are used together for the inter-row differential blasting with the same segment and the same horizontal height, thereby improving the ore recovery rate of the access and ensuring sufficient compensation space for the subsequent deep holes. The application provides sufficient compensation space for the front row of the access, greatly reduces the number of large blocks generated by the front row of the access, comprehensively improves the ore recovery amount of the whole access, and ensures sufficient compensation space for the subsequent deep holes in the access, thereby improving the ore recovery rate of the front row. BRIEF DESCRIPTION OF DRAWINGS

[0013] The application will be further described in detail below in combination with the drawings and specific embodiments.

[0014] Figure 1 is a deep hole design structure schematic diagram of the application;

[0015] Figure 2 is a deep hole design structure schematic diagram of the application;

[0016] Figure 3 is a deep hole design structure schematic diagram of the application;

[0017] Figure 4 is a deep hole design structure schematic diagram of the application;

[0018] Figure 5 is a deep hole design structure schematic diagram of the application;

[0019] Figure: 1 is a cutting lane; 2 is a heading; 3 is a deep hole in the cutting lane; 31 is the last row of deep holes in the cutting lane; 4 is a deep hole in the vertical heading; 41 is the first row of deep holes in the vertical heading; 42 is a No. 1 hole in the vertical heading; 43 is a side hole in the vertical heading; 5 is a deep hole in the heading; 51 is the first row of deep holes in the heading; 52 is the second row of deep holes in the heading; 53 is the initiation point of the deep hole in the heading; 54 is a separate section; a is the angle of the side hole; d is the hole bottom distance; L is the control range. DETAILED DESCRIPTION

[0020] For the convenience of understanding, the arrangement between the rows of the fan-shaped structure in the deep holes in the cutting lane, the deep holes in the heading, and the deep holes in the vertical heading is defined as "row", and the arrangement of each No. 1 hole (No. 2, No. 3, etc.) is defined as "column".

[0021] The present application discloses a blasting method for an underground right-angle roadway, wherein the right-angle roadway is formed by the intersection of a cutting lane and a heading, and the method comprises the following steps: Figure 1 、 Figure 4 As shown in the figure, the deep holes in the cutting lane 3 are arranged in the cutting lane of the right-angle roadway; each row of deep holes in the cutting lane 3 is designed as a fan-shaped structure composed of a plurality of deep holes, and the plurality of rows of deep holes in the cutting lane 3 are arranged along the center line of the cutting lane, and the last row of deep holes in the cutting lane 31 is designed on the left side of the center line of the heading; each row of deep holes in the cutting lane 3 is designed with two side hole angles a of 50°-53°, a row spacing of 1.7-1.9 meters, a hole bottom distance d of 1.8-2 meters, and a roadway center height of 1.5 meters; the hole bottom distance d is generally selected according to the ore of 1.8m and the rock of 2m, and can be adjusted according to the actual situation; the side hole angle a is the angle between the most side deep hole in each row and the ground of the right-angle roadway, the row spacing is the distance between each row of deep holes in the cutting lane 3 and the adjacent deep holes in the cutting lane along the center line of the cutting lane, the hole bottom distance d is the distance between the hole bottoms of the adjacent deep holes in a single row of deep holes in the cutting lane, and the roadway center height is the height of the intersection point of all deep holes in a single row of deep holes in the cutting lane to the ground of the cutting lane.

[0022] Figure 1 、 Figure 4As shown in the drawing, the in-road deep hole 5 is arranged in the in-road 2 of the right-angle roadway; the in-road deep hole 5 is designed with several rows, each row of in-road deep holes 5 is composed of several in-road deep holes in a fan-shaped structure, and the several rows of in-road deep holes 5 are arranged along the in-road center line direction; the first row 51 of in-road deep holes is closest to the cutting roadway 1 and is located at a position 3-5 meters away from the center line of the cutting roadway; each row of in-road deep holes 5 is designed according to the side hole angle α of 50°-53°, the row spacing of 1.7-1.9 meters, and the hole bottom distance d of 1.8-2 meters; the hole bottom distance d is generally selected according to the ore of 1.8m and the rock of 2m, which can be adjusted according to the actual situation; the side hole angle α is the angle between the most edge in-road deep hole of each row and the ground of the right-angle roadway, the row spacing is the distance between each row of in-road deep holes and the adjacent in-road deep holes along the in-road center line direction, and the hole bottom distance d is the distance between the hole bottoms of the adjacent in-road deep holes in a single row of in-road deep holes.

[0023] (2) Figure 1 , Figure 2 , Figure 4 As shown in the drawing, the vertical in-road deep hole 4 is arranged in the intersection range of the cutting roadway 1 and the in-road 2; the vertical in-road deep hole 4 is located on the side of the in-road center line away from the cutting roadway, and several rows are arranged along the in-road center line direction; each row of vertical in-road deep holes 4 is arranged in a fan shape by several in-road deep holes, the in-road deep hole closest to the cutting roadway is the vertical in-road deep hole No. 42, the in-road deep hole farthest from the cutting roadway is the vertical in-road deep hole side hole 43, and the remaining in-road deep holes are distributed between the No. 1 hole and the side hole; the row surface of each row of vertical in-road deep holes 4 is perpendicular to the in-road center line; the position of the first row 41 of vertical in-road deep holes is 1.5 meters away from the in-road top end, and the position of the last row of vertical in-road deep holes is the other side of the roadway side of the cutting roadway 1; the control range L of the vertical in-road deep hole is 7.5 meters, the left control range is the in-road center line, and the right control range is the in-road side of the in-road, that is, the in-road center is taken as the base point, and the right side within 7.5 meters is the control range; the angle between the vertical in-road deep hole No. 42 and the ground of the right-angle roadway is 90°, the angle between the vertical in-road deep hole side hole 43 and the ground of the right-angle roadway, that is, the side hole angle α, is 52°, the hole bottom distance d of each row of vertical in-road deep holes is 1.8-2m, and the row spacing of the vertical in-road deep hole is 0.2-0.3m; the row spacing is the distance between each row of vertical in-road deep holes and the adjacent vertical in-road deep holes along the in-road center line direction, and the hole bottom distance d is the distance between the hole bottoms of the adjacent in-road deep holes in the vertical in-road deep hole.

[0024] (3) Figure 1 As shown in the drawing, the blasting is mainly divided into four parts: the first part is the normal blasting of the cutting roadway 1, including the first row to the penultimate row of the cutting roadway deep hole 3, according to the geological data of the cutting roadway 1, the blasting design is made according to the ore blasting of 1-2 rows and the rock blasting of 2-3 rows, and generally the "V" type blasting is adopted, that is, the detonation point is placed in the center of the roadway.

[0025] Figure 1 , Figure 2 As shown, the second part is the blasting at right angles, including the last row of deep holes 31 in the cutting tunnel and all the deep holes 4 in the vertical approach. The last row of deep holes 31 in the cutting tunnel is set as the first column of the right-angle blasting. All the first holes 42 in the vertical approach form the second column, all the second holes form the third column, and so on, with all the side holes 43 in the vertical approach forming the last column. Every two columns of blasting constitute a segment, and the segments are detonated sequentially, with the segment difference controlled within 50-100ms. The technological principle of using the deep holes 4 in the vertical approach and the last row of deep holes 31 in the cutting tunnel to blast together is as follows: Considering the site factors, if two rows of deep holes in the cutting tunnel are selected, the blasting effect in the cutting tunnel will be affected due to the excessive number of blasting rows and the excessively large resistance line, thus affecting the compensation space of the approach. If the deep holes in the vertical approach are blasted separately, because the center line of the approach is off from the cutting tunnel position, after the last row of deep holes 31 in the cutting tunnel is blasted, a large amount of explosive material will flow into the tunnel and bury the deep holes in the vertical approach, ultimately making it impossible to load explosives.

[0026] Figure 1 , Figure 3 As shown, the third part involves the blasting of the first row 51 and the second row 52 of the deep holes in the approach. Considering that after all the deep holes 3 in the cutting tunnel are blasted, there is ample compensation space on one side of the cutting tunnel 1, the approach blasting center (detonation point) is shifted 1 to 2 deep holes towards the cutting tunnel 1. According to the design concept of "V" shaped blasting, the segments on both sides of the detonation point correspond. Since the detonation point is shifted towards the cutting tunnel 1, there will be extra deep holes on the side away from the cutting tunnel, that is, there is no segment on the other side centered on the detonation point. The extra deep holes are used as separate segments 54 for micro-delay blasting. The segment difference between the separate segment 54 of micro-delay blasting and the approach deep holes of "V" shaped blasting is controlled within 50 to 100 ms.

[0027] Figure 1 As shown, the fourth part is the normal blasting of the deep hole 5 in the approach, including the third to the last row of the deep hole 5 in the approach. According to the geological data of the cutting roadway, the blasting design is carried out according to the mine blasting 1 to 2 rows and the rock blasting 2 to 3 rows. Generally, "V" type blasting is adopted, that is, the detonation point is placed in the center of the roadway.

[0028] Example: The blasting method for the right-angle tunnel in this mine adopts the following process.

[0029] (1) Figure 1 , Figure 5As shown, the cutting roadway middle hole 3 is arranged in the cutting roadway 1 of the right-angle roadway; the cutting roadway middle hole 3 is designed with several rows, each row of the cutting roadway middle hole is composed of several middle holes in a fan-shaped structure, the several rows of the cutting roadway middle hole 3 are arranged along the cutting roadway center line direction, and the last row 31 of the cutting roadway middle hole is designed on the left side of the roadway center line; each row of the cutting roadway middle hole is designed according to two edge hole angles α of 50°, a row spacing of 1.7 meters, a hole bottom spacing d of 1.8 meters, a roadway center height of 1.5 meters, and a control range L of the middle hole of 15 meters.

[0030] Figure 1 Figure 5 As shown, the roadway middle hole 5 is arranged in the roadway 2 of the right-angle roadway; the roadway middle hole 5 is designed with several rows, each row of the roadway middle hole 5 is composed of several middle holes in a fan-shaped structure, and the several rows of the roadway middle hole 5 are arranged along the roadway center line direction; the first row 51 of the roadway middle hole 5 is closest to the cutting roadway 1 and is located at a position of 3-5 meters away from the cutting roadway center line; each row of the roadway middle hole 5 is designed according to an edge hole angle α of 50°, a row spacing of 1.7 meters, and a hole bottom spacing d of 1.8 meters.

[0031] (2) Figure 1 Figure 5 As shown, the vertical roadway middle hole 4 is arranged in the intersection range of the cutting roadway 1 and the roadway 2; the vertical roadway middle hole 4 is located on the side of the roadway center line away from the cutting roadway 1, and is arranged in several rows along the roadway center line direction; each row of the vertical roadway middle hole 4 is composed of several middle holes arranged in a fan shape, Figure 5 As shown, the seven middle holes are arranged in a fan shape, the middle hole closest to the cutting roadway is the vertical roadway middle hole No. 42, the middle hole farthest from the cutting roadway is the vertical roadway middle hole edge hole 43, and the remaining middle holes are distributed between the No. 1 hole and the edge hole; the row surface of each row of the vertical roadway middle hole 4 is perpendicular to the roadway center line; the position of the first row 41 of the vertical roadway middle hole is 1.5 meters away from the top end of the roadway, and the position of the last row of the vertical roadway middle hole is the other side of the roadway support position of the cutting roadway 1; the control range L of the vertical roadway middle hole 4 is 7.5 meters; the angle between the vertical roadway middle hole No. 42 of each row and the ground of the right-angle roadway is 90°, the angle between the vertical roadway middle hole edge hole 43 and the ground of the right-angle roadway is 52°, the hole bottom spacing d of each row of the vertical roadway middle hole 4 is 1.8m, and the row spacing of the vertical roadway middle hole is 0.25m.

[0032] (3) The blasting is mainly divided into four parts: Figure 1 As shown, the first part is the normal blasting of the cutting roadway 1, including the first row to the penultimate row of the cutting roadway middle hole 3, according to the geological data of the cutting roadway 1, the blasting design is made according to 1-2 rows of mine blasting, generally adopting "V" type blasting, that is, the detonation point is placed in the center of the roadway.

[0033] ​​Figure 1 , Figure 2 As shown, the second part is the blasting at right angles, including the last row 31 of deep holes in the cutting tunnel and all the deep holes 4 of the vertical approach. The last row 31 of deep holes in the cutting tunnel is the first column of blasting at right angles. All the first holes 42 of the deep holes in the vertical approach form the second column, all the second holes form the third column, and so on. All the side holes 43 of the deep holes in the vertical approach, i.e., the seventh hole, form the eighth column. Every two columns of blasting are a segment, and the segment difference is controlled between 50 and 100 ms. In this embodiment, the first and second columns of all deep holes are set to a 0 ms segment, the third and fourth columns of all deep holes are set to a 50 ms segment, the fifth and sixth columns of all deep holes are set to a 100 ms segment, and the seventh and eighth columns of all deep holes are set to a 200 ms segment, organizing 8 columns of micro-delay blasting.

[0034] Figure 1 , Figure 3 As shown, the third part involves the blasting of the first row 51 and the second row 52 of the deep holes in the approach. Considering that after all the deep holes 3 in the cutting tunnel are blasted, there is ample compensation space on one side of the cutting tunnel, the blasting center (detonation point) of the approach is shifted one deep hole towards the cutting tunnel. According to the design concept of "V" shaped blasting, the segments on both sides of the detonation point correspond. Since the detonation point is shifted towards the cutting tunnel, there will be extra deep holes on the side away from the cutting tunnel, that is, there is no segment on the other side centered on the detonation point. The extra deep holes are used as separate segments 54 for micro-delay blasting. The segment difference between the separate segment 54 of micro-delay blasting and the deep holes in the approach of "V" shaped blasting is controlled within 50ms.

[0035] Figure 1 As shown, the fourth part is the normal blasting of the deep hole 5 in the approach, including the third to the last row of the deep hole 5 in the approach. According to the geological data of the cutting roadway, the blasting design is carried out according to the mine blasting 1 to 2 rows. Generally, "V" type blasting is adopted, that is, the detonation point is placed in the center of the roadway.

[0036] The on-site implementation of this blasting method reduced the proportion of large blocks by 5%, increased the ore recovery rate at the right-angle roadway location by 1800-2200 tons, and ensured sufficient compensation space for subsequent medium-deep hole blasting.

Claims

1. A method of blasting a rectangular intersection in a mine, characterized in that, The method process is: 1) setting a cutting roadway middle hole (3) in the cutting roadway (1) of the right-angle roadway, and setting a roadway middle hole (5) in the roadway (2) of the right-angle roadway; 2) setting a vertical roadway middle hole (4) in the intersection range of the cutting roadway (1) and the roadway (2); the vertical roadway middle hole (4) is located on the side of the roadway center line far away from the cutting roadway, and a plurality of rows are arranged along the direction of the roadway center line; each row of the vertical roadway middle hole (4) is arranged in a fan shape by a plurality of middle holes, the vertical roadway middle hole No. 1 (42) is closest to the cutting roadway, the vertical roadway middle hole edge hole (43) is farthest away from the cutting roadway, and the row surface of each row of the vertical roadway middle hole (4) is perpendicular to the roadway center line; 3) the cutting roadway middle hole (3) is exploded except the last row (31) of the cutting roadway middle hole close to the roadway; then the last row (31) of the cutting roadway middle hole and the vertical roadway middle hole (4) are exploded by using the row interval millisecond initiation mode; finally, the roadway middle hole (5) is exploded; the row interval millisecond initiation mode is that the last row (31) of the cutting roadway middle hole is the first blasting column, each vertical roadway middle hole No. 1 (42) is the second blasting column, and the vertical roadway middle hole edge hole (43) is arranged in sequence; every two columns of blasting columns are a section position and are exploded in sequence.

2. A method of blasting a rectangular tunnel in a mine according to claim 1, characterized in that: In the step 2), the angle between each vertical roadway middle hole No. 1 (42) and the ground of the right-angle roadway is 90°, and the angle between the vertical roadway middle hole edge hole (43) and the ground of the right-angle roadway is 52°.

3. A method of blasting a straight tunnel according to claim 1, characterized in that: In the step 2), the hole bottom distance of each row of the vertical roadway middle hole (4) is 1.8 m to 2 m.

4. A method of blasting a straight tunnel according to claim 1, characterized in that: In the step 2), the row distance of the vertical roadway middle hole (4) is 0.2 m to 0.3 m.

5. A method of blasting a straight tunnel according to claim 1, characterized in that: The section position difference of the row interval millisecond initiation mode is controlled to be 50 to 100 ms.

6. The method according to any one of claims 1 to 5, wherein: In the step 3), when the roadway middle hole (5) is exploded, the initiation points of the first row (51) and the second row (52) of the roadway middle hole are offset to the direction of the cutting roadway (1) by 1 to 2 middle holes, and a single section position (54) is arranged in the middle hole of the first row and the second row far away from the cutting roadway to organize millisecond blasting.

7. A method of blasting a straight tunnel according to claim 6, characterised in that: The section position difference between the single section position (54) of the millisecond blasting and the remaining roadway middle hole (5) is controlled to be 50 to 100 ms.

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