CN110595308B - Method for treating goaf by ultra-deep hole blasting of strip mine - Google Patents
Method for treating goaf by ultra-deep hole blasting of strip mine Download PDFInfo
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- CN110595308B CN110595308B CN201910889716.4A CN201910889716A CN110595308B CN 110595308 B CN110595308 B CN 110595308B CN 201910889716 A CN201910889716 A CN 201910889716A CN 110595308 B CN110595308 B CN 110595308B
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- 238000005422 blasting Methods 0.000 title claims abstract description 45
- 238000000034 method Methods 0.000 title claims abstract description 18
- 238000005520 cutting process Methods 0.000 claims abstract description 29
- 238000001514 detection method Methods 0.000 claims abstract description 10
- 238000005553 drilling Methods 0.000 claims abstract description 10
- 239000002893 slag Substances 0.000 claims abstract description 4
- 239000002360 explosive Substances 0.000 claims description 17
- 238000005474 detonation Methods 0.000 claims description 4
- 239000000839 emulsion Substances 0.000 claims description 4
- 230000008878 coupling Effects 0.000 claims description 3
- 238000010168 coupling process Methods 0.000 claims description 3
- 238000005859 coupling reaction Methods 0.000 claims description 3
- 238000005065 mining Methods 0.000 abstract description 15
- 238000004519 manufacturing process Methods 0.000 abstract description 6
- 230000002093 peripheral effect Effects 0.000 abstract 1
- 238000004880 explosion Methods 0.000 description 8
- 239000011435 rock Substances 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 238000009826 distribution Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 229910001018 Cast iron Inorganic materials 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 101150086005 gob-1 gene Proteins 0.000 description 1
- 230000000977 initiatory effect Effects 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21C—MINING OR QUARRYING
- E21C37/00—Other methods or devices for dislodging with or without loading
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F42—AMMUNITION; BLASTING
- F42D—BLASTING
- F42D1/00—Blasting methods or apparatus, e.g. loading or tamping
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F42—AMMUNITION; BLASTING
- F42D—BLASTING
- F42D3/00—Particular applications of blasting techniques
- F42D3/04—Particular applications of blasting techniques for rock blasting
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- Mining & Mineral Resources (AREA)
- Life Sciences & Earth Sciences (AREA)
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Abstract
The invention relates to a method for treating a goaf by ultra-deep hole blasting of a strip mine, which comprises the following steps: detecting a goaf: drilling holes in the goaf part, collecting related information of the range, the roof thickness and the empty field height of the goaf by combining a three-dimensional laser scanner or an underwater sonar scanner, and establishing a three-dimensional address model; perforating a gob, drilling a main blast hole, a cutting hole and an auxiliary hole at the top and the peripheral part of the gob by a geological drilling machine according to the gob form mastered by gob detection data, and arranging a slag bucket for ensuring the hole forming rate at an orifice; charging, backfilling and blasting. By adopting the method for treating the goaf by the ultra-deep hole blasting of the strip mine, the goaf can be treated by caving once, the potential safety hazard of secondary compensation caused by layered treatment when the goaf is stoped is avoided, the technical problem of safety of mining under the condition of the complex goaf of the strip mine is solved, and the guarantee is provided for improving the production capacity of the mine.
Description
Technical Field
The invention belongs to the field of strip mine blasting treatment of a goaf, and particularly relates to a method for treating the goaf by ultra-deep hole blasting of a strip mine.
Background
For historical reasons, open stopes have a large number of unknown underground goafs. And (3) arranging drill holes at a certain interval by using a down-the-hole drill and a cross grid method for the suspected goaf part, collecting information such as the range, the roof thickness, the empty field height and the like of the goaf by combining a three-dimensional laser scanner or an underwater sonar scanner, and treating the goaf by a forced blasting induced caving method. At present, for dead zones with large thickness variation of partial plates (the maximum top plate thickness is 40 meters), extremely irregular distribution and no layered treatment condition, the dead zones can only be collapsed in one time in different areas. Limited by technical conditions, the method can only adopt an avoidance and waiting mode. With the decline of mining level of the mining area, the mining boundary is continuously reduced, thereby not only limiting the production capacity of the strip mine, but also increasing the difficulty of detection and treatment of the subsequent goaf. At present, no relevant report about the technology of treating the goaf by ultra-deep hole blasting in an open stope is found.
Disclosure of Invention
The invention aims to provide a method for treating a goaf by ultra-deep hole blasting of a strip mine.
The invention discloses a method for treating a goaf by ultra-deep hole blasting of a strip mine, which comprises the following steps:
(1) goaf detection
Using a down-the-hole drill for the goaf part, arranging drill holes at a certain interval by adopting a cross grid method, and collecting related information of the range, the roof thickness and the empty field height of the goaf by combining with a three-dimensional laser scanner or underwater sonar scanning to establish a three-dimensional address model;
(2) goaf perforation
According to the goaf form mastered by the goaf detection data, drilling a main blast hole, a cutting hole and an auxiliary hole at the top and the periphery of the goaf by using a geological drilling machine, and arranging a slag bucket for ensuring the hole forming rate at each hole opening;
(3) charging and backfilling
Emulsion explosives are adopted in the main blasting hole, the cutting hole and the auxiliary holes, the explosive loading mode is continuous coupling explosive loading, the explosive loading height is 8-25 m, and the backfill height is 7-8 m;
(4) Blasting
1) Selecting a detonating hole: and at the thickest position of the top plate, more than two primary explosion holes are selected from the primary explosion holes at the position with the highest empty field.
2) Selecting a V-shaped undermining differential detonation sequence, selecting a surface tube with delay of 42ms by a main control row, and selecting a surface tube with delay of 65ms by a row, so that the holes of the same section are detonated at the same time, and the blasting vibration is the largest; the time delay of the inner pipe of the main blasting hole is 375ms, the time delay of the auxiliary hole is 400ms, the main blasting hole is detonated 25ms before the auxiliary hole, and the crushing degree of the top plate of the dead zone can be improved to the maximum extent.
Furthermore, the main blast holes are distributed in the goaf in a rectangular mode, the hole grid parameter is 6 x 6 m, the hole depth is 3 m less than the thickness of a top plate of the goaf, and the hole depth H1The range is 15-30 meters.
Furthermore, the hole positions of the cutting holes are arranged in the boundary of the goaf and are contracted by 5 meters, the hole depth is 3 meters less than the thickness of the top plate of the goaf, and the hole depth H2The range is 38-42 m, and the whole falling of the empty area can be ensured.
Furthermore, the auxiliary hole is arranged on the inner side of the cutting hole with the depth of more than 38m and is 3 meters away from the cutting hole, and the hole depth is larger than the cutting hole H2Shallow 18 m and deep hole H3The range is 20-24 meters. The crushing degree of the top plate of the goaf can be improved to the maximum extent.
The invention has the advantages that: on one hand, the maximum roof thickness can be guaranteed to be within 40 meters, the primary caving of the goaf can be avoided, the potential safety hazard of secondary compensation caused by layered treatment when the goaf is stoped is avoided, on the other hand, the safety technical problem which puzzles mining under the condition of a complex goaf of a strip mine is solved, and guarantee is provided for improving the production capacity of the mine.
By adopting the method for treating the goaf by the ultra-deep hole blasting of the strip mine, the goaf can be treated by caving once, the potential safety hazard of secondary compensation caused by layered treatment when the goaf is stoped is avoided, the technical problem of safety of mining under the condition of the complex goaf of the strip mine is solved, and the guarantee is provided for improving the production capacity of the mine.
Drawings
FIG. 1 is a schematic diagram of open pit cutting blasting hole distribution according to the invention.
Fig. 2 is a schematic diagram of a primary blasthole, a cutting hole and a secondary hole.
FIG. 3 is a plot of open pit blast zone connectivity.
Fig. 4 is a schematic charge of the main blasthole.
Fig. 5 is a schematic view of the charge cutting the hole.
Fig. 6 is a schematic view of the charging of the auxiliary hole.
Fig. 7 is a schematic diagram of the embodiment 1 in which the whole empty area is divided into three explosion areas in total.
Detailed Description
The invention will be further explained with reference to the drawings.
As shown in fig. 1-6, the method for treating a gob by ultra-deep hole blasting in a strip mine comprises the following steps:
(1) goaf detection
For the goaf 1 part, using a down-the-hole drill, arranging drill holes at a certain interval by adopting a cross-grid method, and collecting related information of the goaf range, the roof thickness and the empty field height by combining a three-dimensional laser scanner or an underwater sonar scanner to establish a three-dimensional address model;
(2) goaf perforation
According to the goaf form mastered by the detection data of the goaf 1, drilling a main blast hole 2, a cutting hole 4 and an auxiliary hole 3 at the top and the periphery of the goaf 1 by a geological drill, and arranging a slag bucket for ensuring the pore-forming rate at the hole opening(s) to ensure the pore-forming rate;
the main blast holes 2 are distributed in the gob 1 in a rectangular mode, the hole grid parameters are 6 x 6 m, the hole depth is 3 m less than the thickness of a gob top plate, and the hole depth H1The range is 15-30 meters.
The cutting holes 4 are arranged in the boundary of the goaf and are contracted by 5 meters, the hole depth is 3 meters less than the thickness of the top plate of the goaf, and the hole depth H2The range is 38-42 m, and the whole falling of the empty area can be ensured.
The auxiliary hole 3 is arranged on the inner side of the cutting hole with the depth of more than 38m and is 3 meters away from the cutting hole, and the hole depth is larger than the cutting hole H2Shallow 18 m and deep hole H3The range is 20-24 meters. The crushing degree of the top plate of the goaf can be improved to the maximum extent.
(3) Charging and backfilling
Emulsion explosives are adopted in the main blasting hole 2, the cutting hole 4 and the auxiliary hole 3, the explosive loading mode is continuous coupling explosive loading, the explosive loading height is 10-25 m, and the backfill height is 7-8 m; in the figure, the reference number 5 is a detonating cap, and the reference number 6 is a detonating bullet.
(4) Blasting
1) Selecting a detonating hole: selecting more than two primary blasting holes at the position where the thickness of the top plate of the dead zone is 19-20 m and the height of the dead zone is 20-25 m;
2) selecting a V-shaped undermining differential detonation sequence, selecting a surface tube with delay of 42ms by a main control row, and selecting a surface tube with delay of 65ms by a row, so that the holes of the same section are detonated at the same time, and the blasting vibration is the largest; the time delay of the inner pipe of the main blasting hole is 375ms, the time delay of the auxiliary hole is 400ms, the main blasting hole is detonated 25ms before the auxiliary hole, and the crushing degree of the top plate of the dead zone can be improved to the maximum extent.
Example 1
A rock sub mining area large in Anwu steel arch long-ridge open-cast iron mine is mined along with the descending of the mining depth, when a 288m horizontal south slope is mined, geological drilling is used for drilling and three-dimensional detection is carried out on the interior of the mining area by combining a three-dimensional laser detection system, two ultra-large mining areas are found at the position, the length of the ultra-large mining area is about 110m, the length of the ultra-large mining area is about 50m, the minimum elevation of a bottom plate of the mining area is 210m, the thickness of a top plate is 19-78 m, the thickness of the ultra-large mining area is irregularly distributed, the height of an open field is 10-31 m, and no security pillars are arranged, so that the ore in the rock sub mining area is forced to stop production. Such a complex gob is rare in domestic surface mines, and no practical experience exists in processing similar gobs in our mines.
As shown in fig. 7, the whole empty area is divided into three explosion areas to be processed, wherein the hatched areas i, ii and iii in the figure are respectively one explosion area, and the area i with the smaller thickness of the top plate, the larger height of the empty field, the steeper gradient, the better filling effect and the largest grip performance is selected for preferential explosion. The method comprises the following specific steps:
1) the area with the thickness of the top plate less than or equal to 41m, the shaded area in the figure, can induce the dead zone to fall by one-time blasting, and loose rocks generated after the blasting in the area I fill the residual dead zone along the slope surface of the bottom plate of the dead zone by about 45 degrees.
2) In the area with the thickness of 41-72m of the top plate, the layering processing area in the figure, after the layering height of 24m is processed, the rest part independently forms an explosion area, and the one-time collapse processing condition can be met. To ensure the treatment effect, the boundary of the empty area is treated by cutting blasting.
3) And blasting the rest II and III areas respectively.
4) Blasting in a goaf I area, arranging a main blast hole, a cutting hole and an auxiliary hole in the goaf, wherein the main blast hole is formed by arranging holes in a rectangular shape, the hole grid parameter is 6 x 6 m, the distance between the hole bottom and a goaf top plate is 3 m, and the hole depth is H1The range is 15-30 meters. The cutting holes are arranged in the boundary of the goaf and are contracted by 5 meters, the distance between the hole bottom and the top plate of the goaf is 3 meters, and the hole depth is H2The range is 38-42 m, the whole falling of the empty zone can be ensured, and the blast hole depth of the cutting hole is 41.5-12 m. The auxiliary holes are arranged at the inner side of the cutting hole with the depth of more than 38m, the distance from the cutting hole is 3 meters, the hole depth is 18 meters shallower than the cutting hole, and the hole depth H3The range is 20-24 m, the maximum water depth of the blasting area is 20m, emulsion explosives are filled in all blast holes, the height of a explosive column is 22.5-6.5 m, the backfill height is 7m, and the total explosive amount is 38.8 t. Selecting a V-shaped undermining differential detonation sequence, selecting a surface tube with delay of 42ms by a main control row, and selecting a surface tube with delay of 65ms by a row, so that the holes of the same section are detonated at the same time, and the blasting vibration is the largest; the time delay of the inner pipe of the main blasting hole is 375ms, the time delay of the auxiliary hole is 400ms, the main blasting hole is detonated 25ms before the auxiliary hole, and the crushing degree of the top plate of the dead zone can be improved to the maximum extent. The explosion initiating holes are arranged at the positions where the thickness of the top plate of the dead zone is relatively small and the height of the empty field is relatively high.
5) And (3) treating the goaf II and the goaf III, wherein the method is the same as that of the goaf I, and the perforation depth and the loading amount are properly adjusted according to different thicknesses of the goaf top plates.
6) The areas I, II and III are subjected to goaf blasting treatment, the total number of blast holes is 135, the explosive quantity is 104t, and the explosive quantity is 41.47 ten thousand t. The areas of the I and II dead zones completely collapse, the collapse areas are clearly visible, and after blasting in the area III, the blasting area has no obvious uplift and collapse, so that the residual space in the area III is effectively compensated after blasting in the area II, and the production of large rock sub-ores is comprehensively recovered.
Claims (1)
1. A method for treating a goaf by ultra-deep hole blasting of a strip mine comprises the following steps:
(1) goaf detection
Using a down-the-hole drill for the goaf part, arranging drill holes at a certain interval by adopting a cross grid method, and collecting related information of the range, the roof thickness and the empty field height of the goaf by combining a three-dimensional laser scanner or an underwater sonar scanner to establish a three-dimensional address model;
(2) goaf perforation
According to the goaf form mastered by the goaf detection data, drilling a main blast hole, a cutting hole and an auxiliary hole at the top and the periphery of the goaf by using a geological drilling machine, and arranging a slag bucket for ensuring the hole forming rate at an orifice;
the main blast holes are distributed in a rectangular manner in the goaf 1, the hole grid parameter is 6 x 6 m, the hole depth is 3 m less than the thickness of a top plate of the goaf, and the hole depth H1The range is 15-30 meters;
the hole position of the cutting hole is arranged in the boundary of the goaf and is contracted by 5 meters, the hole depth is 3 meters less than the thickness of the top plate of the goaf, and the hole depth H2The range is 38-42 m, so that the whole falling of the empty area can be ensured;
the auxiliary holes are arranged on the inner sides of the cutting holes with the depth larger than 38m and 3 m away from the cutting holes, and the hole depth is larger than that of the cutting holes H2Shallow 18 m and deep hole H3The range is 20-24 meters;
the crushing degree of the top plate of the goaf can be improved to the maximum extent;
(3) charging and backfilling
Emulsion explosives are adopted in the main blasting hole, the cutting hole and the auxiliary hole, the explosive loading mode is continuous coupling explosive loading, the explosive loading height is 8-25 m, and the backfill height is 7-8 m;
(4) Blasting
1) Selecting a detonating hole: selecting more than two primary blasting holes at the position where the thickness of the top plate of the dead zone is 19-20 m and the height of the dead zone is 20-25 m;
2) selecting a V-shaped undermining differential detonation sequence, selecting a surface tube with delay of 42ms by a main control row, and selecting a surface tube with delay of 65ms by a row, so that the holes of the same section are detonated at the same time, and the blasting vibration is the largest; the time delay of the inner pipe of the main blasting hole is 375ms, the time delay of the auxiliary hole is 400ms, the main blasting hole is detonated 25ms before the auxiliary hole, and the crushing degree of the top plate of the dead zone can be improved to the maximum extent.
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| CN111852554B (en) * | 2020-07-06 | 2021-07-16 | 紫金矿业集团股份有限公司 | Rapid trenching method for large water inrush quantity pit open-pit mine small-block full-section deep one-time blasting |
| CN112146528A (en) * | 2020-08-25 | 2020-12-29 | 中铁十九局集团矿业投资有限公司 | Water-rich blasting treatment method for roof of goaf at lower part of strip mine |
| CN112433205A (en) * | 2020-11-12 | 2021-03-02 | 北京科技大学 | Mining and filling empty roof height detection device, installation method and detection method thereof |
| CN113654424A (en) * | 2021-09-02 | 2021-11-16 | 攀钢集团矿业有限公司 | New horizontal ditching method for deep open pit mine |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102116156A (en) * | 2010-04-28 | 2011-07-06 | 鞍钢集团矿业公司 | Slope expansion and blasting method for mining deep concave open-pit mine by stages |
| CN102927866A (en) * | 2012-11-16 | 2013-02-13 | 鞍钢集团矿业公司 | Open-bench blasting method capable of controlling forward stroke of blasting muck pile |
| CN102967191A (en) * | 2012-12-11 | 2013-03-13 | 中国神华能源股份有限公司 | Blasting method for treatment of gob |
| CN104074543A (en) * | 2014-06-16 | 2014-10-01 | 太原钢铁(集团)有限公司 | Method for processing large-scale underground goaf |
| CN108489348A (en) * | 2018-01-31 | 2018-09-04 | 江西铜业股份有限公司 | A kind of deep hole and the knockdown hard rock air bench blasting method of short-bore |
| CN109211039A (en) * | 2018-09-30 | 2019-01-15 | 中国葛洲坝集团易普力股份有限公司 | A kind of opencast mining method for high temperature goaf |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20020082501A (en) * | 2001-03-20 | 2002-10-31 | 티앤알비 주식회사 | Bench rock blasting method for controlling drill hole space, loading amount and blasting sequence |
-
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- 2019-09-20 CN CN201910889716.4A patent/CN110595308B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102116156A (en) * | 2010-04-28 | 2011-07-06 | 鞍钢集团矿业公司 | Slope expansion and blasting method for mining deep concave open-pit mine by stages |
| CN102927866A (en) * | 2012-11-16 | 2013-02-13 | 鞍钢集团矿业公司 | Open-bench blasting method capable of controlling forward stroke of blasting muck pile |
| CN102967191A (en) * | 2012-12-11 | 2013-03-13 | 中国神华能源股份有限公司 | Blasting method for treatment of gob |
| CN104074543A (en) * | 2014-06-16 | 2014-10-01 | 太原钢铁(集团)有限公司 | Method for processing large-scale underground goaf |
| CN108489348A (en) * | 2018-01-31 | 2018-09-04 | 江西铜业股份有限公司 | A kind of deep hole and the knockdown hard rock air bench blasting method of short-bore |
| CN109211039A (en) * | 2018-09-30 | 2019-01-15 | 中国葛洲坝集团易普力股份有限公司 | A kind of opencast mining method for high temperature goaf |
Non-Patent Citations (1)
| Title |
|---|
| 切割诱导爆破处理群布采空区的实践;米子军;《现代矿业》;20150820;第31卷(第8期);第130-132页 * |
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