CN113188386A - Gel coupling blasting method for roof cutting of coal mine crack-containing roof area - Google Patents
Gel coupling blasting method for roof cutting of coal mine crack-containing roof area Download PDFInfo
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- CN113188386A CN113188386A CN202110498726.2A CN202110498726A CN113188386A CN 113188386 A CN113188386 A CN 113188386A CN 202110498726 A CN202110498726 A CN 202110498726A CN 113188386 A CN113188386 A CN 113188386A
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- blasting
- gel
- hole
- roof
- water
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- 238000005422 blasting Methods 0.000 title claims abstract description 54
- 238000005520 cutting process Methods 0.000 title claims abstract description 24
- 238000000034 method Methods 0.000 title claims abstract description 23
- 239000003245 coal Substances 0.000 title claims abstract description 22
- 238000010168 coupling process Methods 0.000 title claims abstract description 20
- 238000005859 coupling reaction Methods 0.000 title claims abstract description 20
- 230000008878 coupling Effects 0.000 title abstract description 18
- 239000011435 rock Substances 0.000 claims abstract description 20
- 239000000203 mixture Substances 0.000 claims abstract description 18
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 18
- 239000003566 sealing material Substances 0.000 claims abstract description 6
- 238000002347 injection Methods 0.000 claims description 14
- 239000007924 injection Substances 0.000 claims description 14
- 239000000701 coagulant Substances 0.000 claims description 11
- 239000000463 material Substances 0.000 claims description 10
- 238000004513 sizing Methods 0.000 claims description 10
- 239000003292 glue Substances 0.000 claims description 8
- 238000005553 drilling Methods 0.000 claims description 4
- 229920002401 polyacrylamide Polymers 0.000 claims description 4
- 238000007789 sealing Methods 0.000 claims description 4
- 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
- 238000005474 detonation Methods 0.000 claims 1
- 239000002360 explosive Substances 0.000 abstract description 17
- 230000000694 effects Effects 0.000 abstract description 5
- 230000008569 process Effects 0.000 abstract description 5
- 230000015572 biosynthetic process Effects 0.000 abstract description 4
- 238000005755 formation reaction Methods 0.000 abstract description 4
- 239000007787 solid Substances 0.000 abstract description 2
- 238000010276 construction Methods 0.000 abstract 1
- 239000002609 medium Substances 0.000 description 16
- 239000000243 solution Substances 0.000 description 5
- 238000005065 mining Methods 0.000 description 4
- 230000009471 action Effects 0.000 description 3
- 230000005540 biological transmission Effects 0.000 description 3
- 238000004880 explosion Methods 0.000 description 3
- 239000012736 aqueous medium Substances 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000002349 favourable effect Effects 0.000 description 2
- KKCBUQHMOMHUOY-UHFFFAOYSA-N Na2O Inorganic materials [O-2].[Na+].[Na+] KKCBUQHMOMHUOY-UHFFFAOYSA-N 0.000 description 1
- 239000004115 Sodium Silicate Substances 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 238000010586 diagram 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
- 230000021715 photosynthesis, light harvesting Effects 0.000 description 1
- 230000035939 shock Effects 0.000 description 1
- UIIMBOGNXHQVGW-UHFFFAOYSA-M sodium bicarbonate Substances [Na+].OC([O-])=O UIIMBOGNXHQVGW-UHFFFAOYSA-M 0.000 description 1
- 229910000030 sodium bicarbonate Inorganic materials 0.000 description 1
- 229910052911 sodium silicate Inorganic materials 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 239000002470 thermal conductor Substances 0.000 description 1
Images
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 OR ROCK 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
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- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mining & Mineral Resources (AREA)
- Remote Sensing (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- Drilling And Exploitation, And Mining Machines And Methods (AREA)
Abstract
本发明公开一种用于煤矿含裂隙顶板区域切顶的凝胶耦合爆破方法，在跨越了两个甚至多个岩层的欲爆破切顶区域打出若干爆破钻孔，将爆破药柱放入爆破钻孔，使用封孔材料对爆破钻孔进行封堵，然后通过凝胶泵将固定配比的凝胶混合物注入炸药与钻孔孔壁之间。利用凝胶所特有的不流动与半固体状性质，避免了以往采取水介质耦合爆破时，岩层之间交界面处的水介质流失问题；炸药与孔壁之间的耦合性得到了根本保障，减少了无益能量损耗，进而保证了良好的爆破切顶效果。其工艺简单，施工方便，安全可靠，效率极高。
The invention discloses a gel-coupling blasting method for roof cutting in a crack-containing roof area of a coal mine. Several blasting holes are drilled in the area to be blasted and cut across two or even more rock layers, and blasting charge columns are put into the blasting drill. The blasting hole is sealed with a hole sealing material, and then a fixed proportion of the gel mixture is injected between the explosive and the wall of the hole through the gel pump. Using the peculiar non-flowing and semi-solid properties of gel, the problem of water loss at the interface between rock formations when water-medium coupled blasting was used in the past was avoided; the coupling between the explosive and the hole wall was fundamentally guaranteed. The useless energy loss is reduced, thereby ensuring a good blasting and top-cutting effect. The process is simple, the construction is convenient, safe and reliable, and the efficiency is extremely high.
Description
Technical Field
The invention relates to a blasting method for roof cutting and roadway self-forming of a coal mine, belongs to the technical field of coal mine underground mining, and particularly relates to a gel coupling blasting method for roof cutting of a fracture-containing roof area of the coal mine.
Background
In the process of coal mining, particularly when the roof is a multilayer rock stratum with large thickness, along with the continuous propulsion of a working face, the cantilever beam with the coal pillar as a supporting point is suspended without collapsing, the caving gangue of the roof is difficult to fill a goaf, and the concentrated stress borne by the coal pillar is gradually increased at the moment, so that the phenomena of roof sinking, bottom heave and other ore pressure appearing in a roadway of a stoping face are caused, and in severe cases, even rock burst disasters are induced.
In order to cut off stress transmission between top plates and eliminate the threat of a high-stress environment to a roadway, the traditional means is an energy-accumulating 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. At present, the charge mode of the shaped charge blasting topping operation in China is mostly non-coupled charge, and in the charge mode, the coupling medium between the explosive and the hole wall is air; after a large number of field tests, researchers find that the gaps between the explosive and the hole walls are filled with the aqueous medium instead of air, the energy utilization rate of the explosive can be greatly improved, and the top-cutting effect is better.
However, during the blasting and roof cutting operation, if the top plate contains a large number of cracks, a large amount of energy can be dissipated in the crack area when air coupling is adopted; with water coupling, water can flow away along the crevices. When the cut-top zone spans two or even more rock formations with an interface between the rock formations, energy dissipation and water runoff may result. If the efficient utilization of explosive energy is required to be ensured and accurate roof cutting and roadway forming are realized, the area containing cracks and interfaces needs to be treated.
Therefore, a blasting roof cutting self-entry-forming method which is simple in operation and can efficiently utilize the energy of the explosive is needed to be invented for the coal mine roof area containing the cracks.
Disclosure of Invention
Aiming at the problems, the invention provides a gel coupling blasting method for cutting the roof of a coal mine crack-containing roof area. The gel is adopted to replace the traditional air or water medium, the space between the explosive and the wall of the drilled hole 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 aim of blasting roof cutting and roadway forming in the areas of the coal mine containing cracks, interfaces and the like is fulfilled.
In order to solve the above problems, the technical scheme provided by the invention is as follows:
a gel coupling blasting method for cutting the top of a coal mine crack-containing roof area comprises the following steps:
a. constructing a plurality of blasting drill holes (2) on the rock stratum of the top plate (1) in the area containing the fracture or rock stratum interface;
b. the blasting explosive column (3) is sent to the designated position of the blasting drill hole (2), and the orifice of the blasting drill hole (2) is plugged after the detonating line (9) is led out;
c. the glue injection pipe (5) penetrates through the hole sealing material (4) to be 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 body (6) to prepare the mixture with the gelling time T1The gel mixture (11);
e. continuously injecting the gel mixture (11) into the blast hole (2) by using a gel pump (7) until the gel mixture (11) in the blast hole (2) is condensed into gel, wherein the indication number of a pressure gauge is 2-5 MPa, and the continuous injection time is recorded as T2And T is2And T1The following relationship is satisfied:
T2＝2×T1
f. the glue injection pipe (5) is removed, and the pipe opening of the glue injection pipe (5) is plugged;
g. detonating the explosive column (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 performing subsequent hole sealing and blasting operation of blasting and drilling.
Further, in the step d, water, a sizing material and a coagulant are mixed according to a mass ratio of 12-20: 2-5: 1, mixing; the sizing material is water glass; the coagulant is NaHCO 3.
Further, in the step d, the water, the sizing material and the coagulant are mixed according to the mass ratio of 12: 5: 1, and mixing.
Further, in the step e, the indication of the pressure gauge is 2 MPa.
Further, in step h, the gel 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) when injecting a gel mixture into a roof borehole, with continued injection, some of the mixture will flow along the fracture-rock interface, and will gel automatically and lose mobility once the gel formation time is reached. At the moment, gel is filled between the blasting explosive column and the hole wall of the drill hole, so that the coupling of the explosive and the hole wall is realized. The gel is a poor thermal conductor, can greatly reduce the loss of heat, is favorable for maintaining the pressure in the blast hole and is more favorable for the pressure in the hole to do work on the rock mass. Therefore, the gel can be used as a coupling medium to ensure good blasting and top cutting effects;
(2) the gel is used as a coupling energy transfer medium, the compressibility of the gel is small, and the density, the propagation speed of longitudinal waves in the gel and the wave impedance value are all larger than those in an aqueous medium; the better the wave impedance value of the coupling medium and the matching of the coal rock mass, the less the energy of the transmission loss, the larger the strain generated by the coal rock mass is, the more 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 gelling time of the gel medium filled by the gel pump can be adjusted as required, the fastest time can reach 30 seconds, and the rapidness, safety and high efficiency of blasting and top cutting can be ensured.
Drawings
FIG. 1 is a schematic view of the overall structure of the present invention;
FIG. 2 is a schematic diagram of the overall structure of the embodiment of the present invention;
FIG. 3 is a schematic view of a charge configuration according to an embodiment of the present invention;
in the figure: 1. a top plate; 2. blasting and drilling; 3. blasting explosive columns; 4. hole sealing materials; 5. a glue injection pipe; 6. a tank body; 7. a gel pump; 8. a pressure gauge; 9. a detonating circuit; 10. a detonator; 11 gel mixture.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1 to 3, a gel coupling blasting method for roof cutting of a cracked roof area of a coal mine includes the following steps:
1. the specific situation of a top plate 1 of a certain coal seam crest cutting area is inspected, the strength of the top plate is 58-75 MPa, but a plurality of joints and crack sliding surfaces exist in an old top, and a plurality of blasting drill holes 2 with the depth of 16m, the hole diameter of 55mm, the hole interval of 50cm and the drill hole angle of 80 degrees are drilled from the position 10m ahead of a working surface;
2. 3.6kg of blasting explosive column 3 is placed at the specified position of the blasting drill hole 2, and the charging length is 12 m; after the detonating line 9 is led out of the blasting drill hole 2, the hole opening of the blasting drill hole 2 is plugged by using a hole sealing material 4, and the hole sealing length is 4 m;
3. the glue injection pipe 5 penetrates through the hole sealing material 4 to be sequentially connected with a pressure gauge 8, a gel pump 7 and a tank body 6;
4. selecting sodium silicate Na2O·nSiO2As sizing material, NaHCO3As a coagulant, water, sizing material and the coagulant are mixed in a tank body 6 according to the mass ratio of 12: 5: 1, and preparing the gel forming time (T)1) Gel mixture 11 for 2min, and stirring well;
5. injecting the gel mixture 11 into the blast hole 2 by using a gel pump 7 until the gel mixture 11 in the blast hole 2 is condensed into gel, wherein the indication number of a pressure gauge is 2MPa, and the continuous injection time is recorded as T2And T is2And T1The following relationship is satisfied:
T2＝2×T1
6. removing the glue injection pipe 5 and plugging the pipe opening of the glue injection pipe 5;
7. the detonating line 9 is connected with the exploder 10, and the blasting explosive columns 3 are detonated after personnel evacuate to a safe place;
8. polyacrylamide is selected as a gel breaker, a proper amount of polyacrylamide aqueous solution is added into the tank body 6, so that the gel mixture 11 of the tank body 6 cannot be condensed, and the subsequent hole sealing and blasting operation of blasting drilling is carried out.
Along with the continuous increase of coal mining depth, the geological conditions of coal mining become more and more complex, and under the high ground stress environment, the demand of blasting, top cutting and pressure relief on the advanced working face is increasingly urgent. When the cutting area spans a plurality of rock stratums and the operating conditions of structural planes exist among the rock stratums, if the conventional water medium coupling blasting technology is adopted, the water medium flows out along the interface among the rock stratums, and the blasting cutting effect cannot be ensured. In the embodiment, the gel is used as the coupling medium between the emulsion explosive and the hole wall, and the special non-flowing and semi-solid properties of the gel avoid the problem of water medium loss at the interface between rock strata when water medium coupling blasting is adopted in the prior art. And 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 faster than those in water or air, and the loss of useless energy is reduced, so that the energy utilization rate is higher when the gel medium is adopted for energy-gathering blasting, and the roof cutting effect of the coal seam roof is greatly improved.
It is noted that, herein, relational terms such as first and second, and the like may be 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. Also, 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 an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present 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 solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.
Claims (5)
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| 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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| 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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| CN113188386A true CN113188386A (en) | 2021-07-30 |
| CN113188386B CN113188386B (en) | 2024-03-26 |
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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 | A kind of 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 | A kind of 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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