CN113188386B - Gel coupling blasting method for roof cutting of fracture-containing roof area of coal mine - Google Patents
Gel coupling blasting method for roof cutting of fracture-containing roof area of coal mine Download PDFInfo
- Publication number
- CN113188386B CN113188386B CN202110498726.2A CN202110498726A CN113188386B CN 113188386 B CN113188386 B CN 113188386B CN 202110498726 A CN202110498726 A CN 202110498726A CN 113188386 B CN113188386 B CN 113188386B
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- Prior art keywords
- gel
- blasting
- roof
- cutting
- coal mine
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- 238000005422 blasting Methods 0.000 title claims abstract description 52
- 238000005520 cutting process Methods 0.000 title claims abstract description 25
- 239000003245 coal Substances 0.000 title claims abstract description 23
- 238000000034 method Methods 0.000 title claims abstract description 22
- 230000008878 coupling Effects 0.000 title claims abstract description 21
- 238000010168 coupling process Methods 0.000 title claims abstract description 21
- 238000005859 coupling reaction Methods 0.000 title claims abstract description 21
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 20
- 239000011435 rock Substances 0.000 claims abstract description 16
- 239000002360 explosive Substances 0.000 claims abstract description 14
- 230000015572 biosynthetic process Effects 0.000 claims abstract description 10
- 239000000203 mixture Substances 0.000 claims description 15
- 238000002347 injection Methods 0.000 claims description 14
- 239000007924 injection Substances 0.000 claims description 14
- 238000004513 sizing Methods 0.000 claims description 11
- 239000000701 coagulant Substances 0.000 claims description 10
- 239000000463 material Substances 0.000 claims description 9
- 238000005553 drilling Methods 0.000 claims description 7
- 238000004880 explosion Methods 0.000 claims description 5
- 239000003566 sealing material Substances 0.000 claims description 5
- 229920002401 polyacrylamide Polymers 0.000 claims description 4
- 238000007789 sealing Methods 0.000 claims description 4
- 230000000977 initiatory effect Effects 0.000 claims description 3
- 239000000843 powder Substances 0.000 claims description 3
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 claims description 3
- 235000019353 potassium silicate Nutrition 0.000 claims description 2
- 238000005755 formation reaction Methods 0.000 abstract description 8
- 230000008569 process Effects 0.000 abstract description 6
- 230000000694 effects Effects 0.000 abstract description 5
- 238000010276 construction Methods 0.000 abstract 1
- 239000002609 medium Substances 0.000 description 17
- 238000005065 mining Methods 0.000 description 4
- 239000000243 solution Substances 0.000 description 4
- 230000009471 action Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- UIIMBOGNXHQVGW-UHFFFAOYSA-M Sodium bicarbonate Chemical group [Na+].OC([O-])=O UIIMBOGNXHQVGW-UHFFFAOYSA-M 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 2
- 230000002349 favourable effect Effects 0.000 description 2
- 239000004115 Sodium Silicate Substances 0.000 description 1
- 239000012736 aqueous medium Substances 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 238000005474 detonation Methods 0.000 description 1
- 239000000839 emulsion Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000035939 shock Effects 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 229910000030 sodium bicarbonate Inorganic materials 0.000 description 1
- 235000017557 sodium bicarbonate Nutrition 0.000 description 1
- 229910052911 sodium silicate Inorganic materials 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F42—AMMUNITION; BLASTING
- F42D—BLASTING
- F42D1/00—Blasting methods or apparatus, e.g. loading or tamping
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21C—MINING OR QUARRYING
- E21C41/00—Methods of underground or surface mining; Layouts therefor
- E21C41/16—Methods of underground mining; Layouts therefor
- E21C41/18—Methods of underground mining; Layouts therefor for brown or hard coal
-
- 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
Abstract
The invention discloses a gel coupling blasting method for cutting roof in a fracture-containing roof area of a coal mine. By utilizing the unique non-flowing and semisolid properties of the gel, the problem of water medium loss at the interface between rock formations when the coupling blasting of the water medium is adopted in the past is avoided; the coupling between the explosive and the hole wall is fundamentally ensured, the useless energy loss is reduced, and the good blasting roof cutting effect is further ensured. The method has the advantages of simple process, convenient construction, safety, reliability and high efficiency.
Description
Technical Field
The invention relates to a blasting method for roof cutting self-forming roadway of a coal mine, belongs to the technical field of mining of coal mine workers, and particularly relates to a gel coupling blasting method for roof cutting of a roof area containing cracks of the coal mine.
Background
In the coal mining process, particularly when the roof is a plurality of layers of rock stratum with larger thickness, along with the continuous pushing of a working face, a cantilever beam taking a coal pillar as a supporting point is suspended and does not collapse, the goaf is difficult to be filled with gangue falling from the roof, and the concentrated stress born by the coal pillar is gradually increased at the moment, so that roof sinking, bottom drum and other ore pressure manifestations occur in a roadway of a stoping working face, and rock burst disasters can be even induced in severe cases.
In order to cut off the stress transmission between the top plates and eliminate the threat of a high stress environment to a roadway, the traditional means is a concentrated blasting roof cutting method, the length of a cantilever beam is shortened through blasting roof cutting operation, and the bearing stress of a coal pillar is reduced. The current charging modes in the process of carrying out the roof cutting operation of the energy-gathering blasting in China are mostly uncoupled charging, and in the charging modes, a coupling medium between explosive and a hole wall is air; after a large number of field tests, researchers find that using an aqueous medium to replace air to fill gaps between the explosive and the hole wall can greatly improve the energy utilization rate of the explosive, and the roof cutting effect is better.
However, during blasting roof cutting operations, if the roof contains a large number of cracks, when air coupling is used, a large amount of energy is dissipated in the crack area; when water coupling is used, water will flow along the fracture. And when the truncated area spans two or even more strata, interfaces between strata are present, resulting in dissipation of energy and drainage of water. If the efficient utilization of the explosive energy is to be ensured, accurate roof cutting and lane forming are realized, and the area containing cracks and interfaces is required to be treated.
Therefore, the invention is necessary to invent a blasting roof-cutting self-lane forming method which is used for the coal mine fracture-containing roof area and is simple to operate and efficiently utilizes the explosive energy.
Disclosure of Invention
Aiming at the problems, the invention provides a gel coupling blasting method for cutting the roof of a fracture-containing roof area of a coal mine. The gel is adopted to replace the traditional air or water medium, the space between the explosive and the borehole wall is filled, the explosion energy is completely transmitted to the roof rock stratum through the gel medium, the efficient utilization of the explosive energy is ensured, and the purposes of blasting, roof cutting and roadway forming in the areas such as cracks, interfaces and the like of the coal mine are realized.
In order to solve the problems, the technical scheme provided by the invention is as follows:
the gel coupling blasting method for cutting the roof of the fracture-containing roof area of the coal mine comprises the following steps:
a. constructing a plurality of blasting drillings (2) into the rock formation of the top plate (1) in the area containing the fissures or the rock formation interface;
b. sending the blasting powder column (3) into a designated position of the blasting drilling hole (2), and plugging an orifice of the blasting drilling hole (2) after leading out an initiating circuit (9);
c. the rubber injection pipe (5) penetrates through the hole sealing material (4) and is sequentially connected with the pressure gauge (8), the gel pump (7) and the tank body (6);
d. mixing water, sizing material and coagulant in a tank (6) to prepare the sizing time T 1 Is a gel mixture (11);
e. continuously injecting the gel mixture (11) into the blasting borehole (2) by using a gel pump (7) until the gel mixture (11) in the blasting borehole (2) is coagulated into gel, wherein the pressure gauge is 2-5 MPa, and the continuous injection time is recorded as T 2 And T is 2 And T 1 The following relationship is satisfied:
T 2 ＝2×T 1
f. dismantling the rubber injection pipe (5) and plugging the pipe orifice of the rubber injection pipe (5);
g. detonating the blasting cartridge (3);
h. and adding a gel breaker into the tank body (6) to prevent the gel mixture (11) of the tank body (6) from being coagulated, and carrying out hole sealing and blasting operation of subsequent blasting holes.
Further, in the step d, the mass ratio of water to sizing material to coagulant is 12-20: 2 to 5:1, mixing in proportion; the sizing material is water glass; the coagulant is NaHCO3.
Further, in the step d, water, sizing material and coagulant are mixed according to the mass ratio of 12:5: 1.
Further, in the step e, the pressure gauge number is 2MPa.
Further, in the step h, the breaker is polyacrylamide.
Compared with the prior art, the invention has the beneficial effects that:
compared with the prior art, the invention has the beneficial effects that:
(1) As the gel mixture is injected into the roof borehole, a portion of the mixture will flow along the interface of the fracture and formation with continued injection, automatically gelling and losing mobility once the gelling time is reached. At this time, gel is filled between the explosive column and the wall of the hole, so that the coupling of the explosive and the wall of the hole is realized. The gel is a bad heat conductor, can greatly reduce heat loss, is favorable for maintaining the pressure in the blasthole, and is more favorable for the pressure in the hole to apply work to the rock mass. Therefore, the gel can ensure good blasting and roof cutting effects as a coupling medium;
(2) The gel is used as a coupling energy-transfer medium, and the compressibility of the gel is small, and the propagation speed and wave impedance value of the density and longitudinal wave in the gel are all larger than those in the water medium; the better the matching between the wave impedance value of the coupling medium and the coal rock mass is, the less energy is transmitted and the larger the strain generated by the coal rock mass is caused, the gel enters the rock stratum crack of the top plate, the high-efficiency transmission of the explosion energy is realized, and the energy utilization rate is far higher than the air or water coupling condition;
(3) By adjusting the concentration of the coagulant, the gel forming time of the gel medium poured by the gel pump can be adjusted as required, and can reach 30 seconds at maximum, thereby ensuring the quick, safe and high-efficiency of blasting and roof cutting.
Drawings
FIG. 1 is a schematic diagram of the overall structure of the present invention;
FIG. 2 is a schematic diagram of the overall structure of an embodiment of the present invention;
FIG. 3 is a schematic diagram of a charge configuration according to an embodiment of the present invention;
in the figure: 1. a top plate; 2. blasting and drilling holes; 3. blasting the grain; 4. a hole sealing material; 5. a rubber injection pipe; 6. a tank body; 7. a gel pump; 8. a pressure gauge; 9. a detonation circuit; 10. a detonator; 11 gel mixture.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions in the embodiments of the present invention will be clearly and completely described in the following in conjunction with the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Referring to fig. 1 to 3, a gel coupling blasting method for roof cutting of a roof area containing cracks in a coal mine comprises the following steps:
1. examining the concrete condition of a roof 1 in a region to be cut of a certain coal seam, wherein the strength of the roof is 58-75 MPa, but a plurality of joint and crack sliding surfaces exist in the old roof, and a plurality of blasting holes 2 with the depth of 16m, the aperture of 55mm, the hole spacing of 50cm and the drilling angle of 80 degrees are drilled from the position of a 10m advanced working surface;
2. 3.6kg of blasting powder grain 3 is placed at a designated position of a blasting borehole 2, and the charging length is 12m; after the detonating circuit 9 is led out of the blasting borehole 2, the hole opening of the blasting borehole 2 is plugged by using a hole sealing material 4, and the hole sealing length is 4m;
3. the rubber injection pipe 5 penetrates through the hole sealing material 4 and is sequentially connected with the pressure gauge 8, the gel pump 7 and the tank 6;
4. selecting sodium silicate Na 2 O·nSiO 2 As a sizing material, naHCO 3 As the coagulant, water, sizing material and coagulant are mixed in the tank 6 according to the mass ratio of 12:5:1, is mixed in proportion, and is configured into a gel for a time (T 1 ) Gel mixture 11 for 2min and stirred well;
5. injecting the gel mixture 11 into the blasting borehole 2 by using the gel pump 7 until the gel mixture 11 in the blasting borehole 2 is coagulated into gel, wherein the pressure gauge is 2MPa, and the continuous injection time is recorded as T 2 And T is 2 And T 1 The following relationship is satisfied:
T 2 ＝2×T 1
6. dismantling the rubber injection pipe 5 and plugging the pipe orifice of the rubber injection pipe 5;
7. the detonating circuit 9 is connected with the exploder 10, so that the explosive column 3 is detonated after personnel are evacuated to a safe place;
8. and (3) selecting polyacrylamide as a gel breaker, adding a proper amount of polyacrylamide aqueous solution into the tank body 6, preventing the gel mixture 11 of the tank body 6 from being coagulated, and carrying out hole sealing and blasting operation of subsequent blasting holes.
Along with the continuous increase of the coal mining depth, the geological conditions of the coal mining are increasingly complex, and the requirement of blasting, roof cutting and pressure relief on the advanced working face is increasingly urgent under the high-ground-stress environment. When the roof cutting area spans a plurality of rock formations and working conditions of structural surfaces exist among the rock formations, if a conventional water medium coupling blasting technology is adopted, water medium flows out along interfaces among the rock formations, and the blasting roof cutting effect cannot be ensured. In the embodiment, gel is adopted as a coupling medium between the emulsion explosive and the hole wall, and the unique non-flowing and semisolid property of the gel is adopted, so that the problem of water medium loss at the interface between rock formations when the coupling blasting of the water medium is adopted in the past is avoided. The gel medium is used as an energy transfer medium, the compressibility of the gel medium is small, the explosion shock wave and the stress wave are much faster than those in water or air, and the useless energy loss is reduced, so that the energy utilization rate is higher when the gel medium is adopted for gathering energy explosion, and the roof cutting effect of a coal seam roof is greatly improved.
It is noted that relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.
The above embodiments are only for illustrating the technical solution of the present invention, and are not limiting; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention.
Claims (1)
1. A gel coupling blasting method for cutting roof of a roof area containing cracks of a coal mine is characterized in that gel is adopted to replace air or water medium, space between explosive and the wall of a borehole is filled, explosion energy is transmitted to roof strata through gel medium, high-efficiency utilization of the explosive energy is guaranteed, and the purposes of blasting roof cutting and roadway forming of the crack-containing and interface area of the coal mine are achieved; the method comprises the following steps:
a. constructing a blast borehole (2) into the rock formation of the top plate (1) in a region containing a fracture or rock formation interface;
b. sending the blasting powder column (3) into a designated position of the blasting drilling hole (2), and plugging an orifice of the blasting drilling hole (2) after leading out an initiating circuit (9);
c. the rubber injection pipe (5) penetrates through the hole sealing material (4) and is sequentially connected with the pressure gauge (8), the gel pump (7) and the tank body (6);
d. mixing water, sizing material and coagulant in a tank (6) to prepare the sizing time T 1 Is a gel mixture (11);
e. continuously injecting the gel mixture (11) into the blasting borehole (2) by using a gel pump (7) until the gel mixture (11) in the blasting borehole (2) is coagulated into gel, wherein the pressure gauge is 2-5 MPa, and the continuous injection time is recorded as T 2 And T is 2 And T 1 The following relationship is satisfied:
T 2 =2×T 1
f. dismantling the rubber injection pipe (5) and plugging the pipe orifice of the rubber injection pipe (5);
g. connecting an initiating circuit (9) with a detonator (10) to ensure that the blasting grain (3) is detonated after personnel are evacuated to a safe place;
h. adding a gel breaker into the tank body (6) to ensure that the gel mixture (11) of the tank body (6) cannot be coagulated, and carrying out hole sealing and blasting operation of subsequent blasting holes;
in the step d, water, sizing material and coagulant are mixed according to the mass ratio of 12-20: 2-5: 1, mixing in proportion; the sizing material is water glass; the coagulant is NaHCO 3 ；
In the step h, the gel breaker is polyacrylamide.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110498726.2A CN113188386B (en) | 2021-05-08 | 2021-05-08 | Gel coupling blasting method for roof cutting of fracture-containing roof area of coal mine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110498726.2A CN113188386B (en) | 2021-05-08 | 2021-05-08 | Gel coupling blasting method for roof cutting of fracture-containing roof area of coal mine |
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| Publication Number | Publication Date |
|---|---|
| CN113188386A CN113188386A (en) | 2021-07-30 |
| CN113188386B true CN113188386B (en) | 2024-03-26 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202110498726.2A Active CN113188386B (en) | 2021-05-08 | 2021-05-08 | Gel coupling blasting method for roof cutting of fracture-containing roof area of coal mine |
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Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU826022A1 (en) * | 1979-08-07 | 1981-04-30 | Tsnii Olovyannoj Promy | Gel-forming composition for stemming blast holes and wells |
| US5810098A (en) * | 1997-01-10 | 1998-09-22 | Wathen; Boyd J. | Method of breaking slabs and blocks of rock from rock formations and explosive shock transmitting and moderating composition for use therein |
| JP2009168374A (en) * | 2008-01-17 | 2009-07-30 | Ohbayashi Corp | Smooth blasting construction method |
| CN101767975A (en) * | 2010-01-29 | 2010-07-07 | 北京工业大学 | Composite gel fire control material for treating coal seam fire |
| CN102838339A (en) * | 2012-08-28 | 2012-12-26 | 李云飞 | Gel-type chemical stemming and preparation method thereof |
| CN104567564A (en) * | 2014-12-15 | 2015-04-29 | 中国矿业大学 | Aqueous medium non-coupling charge explosion method of jointed rock mass |
| CN109578053A (en) * | 2019-01-29 | 2019-04-05 | 陈舸 | A kind of sodium silicate gel combined casting material and its preparation method and application |
| CN111502700A (en) * | 2020-04-24 | 2020-08-07 | 哈尔滨龙源河矿山机械技术开发有限公司 | Tunnel sealing surrounding rock arch and construction method thereof |
| CN112097581A (en) * | 2020-09-17 | 2020-12-18 | 武汉大学 | Blast hole charging structure and charging method |
| CN112129185A (en) * | 2020-09-17 | 2020-12-25 | 武汉大学 | Water-containing blast hole charging device and charging method |
| CN112179228A (en) * | 2020-09-29 | 2021-01-05 | 太原理工大学 | Deep hole subsection blasting joint cutting control top plate overall collapse method |
-
2021
- 2021-05-08 CN CN202110498726.2A patent/CN113188386B/en active Active
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU826022A1 (en) * | 1979-08-07 | 1981-04-30 | Tsnii Olovyannoj Promy | Gel-forming composition for stemming blast holes and wells |
| US5810098A (en) * | 1997-01-10 | 1998-09-22 | Wathen; Boyd J. | Method of breaking slabs and blocks of rock from rock formations and explosive shock transmitting and moderating composition for use therein |
| JP2009168374A (en) * | 2008-01-17 | 2009-07-30 | Ohbayashi Corp | Smooth blasting construction method |
| CN101767975A (en) * | 2010-01-29 | 2010-07-07 | 北京工业大学 | Composite gel fire control material for treating coal seam fire |
| CN102838339A (en) * | 2012-08-28 | 2012-12-26 | 李云飞 | Gel-type chemical stemming and preparation method thereof |
| CN104567564A (en) * | 2014-12-15 | 2015-04-29 | 中国矿业大学 | Aqueous medium non-coupling charge explosion method of jointed rock mass |
| CN109578053A (en) * | 2019-01-29 | 2019-04-05 | 陈舸 | A kind of sodium silicate gel combined casting material and its preparation method and application |
| CN111502700A (en) * | 2020-04-24 | 2020-08-07 | 哈尔滨龙源河矿山机械技术开发有限公司 | Tunnel sealing surrounding rock arch and construction method thereof |
| CN112097581A (en) * | 2020-09-17 | 2020-12-18 | 武汉大学 | Blast hole charging structure and charging method |
| CN112129185A (en) * | 2020-09-17 | 2020-12-25 | 武汉大学 | Water-containing blast hole charging device and charging method |
| CN112179228A (en) * | 2020-09-29 | 2021-01-05 | 太原理工大学 | Deep hole subsection blasting joint cutting control top plate overall collapse method |
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| CN113188386A (en) | 2021-07-30 |
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