CN104847406B - Method for fracturing retained filled wall of adjacent coal face - Google Patents
Method for fracturing retained filled wall of adjacent coal face Download PDFInfo
- Publication number
- CN104847406B CN104847406B CN201510134567.2A CN201510134567A CN104847406B CN 104847406 B CN104847406 B CN 104847406B CN 201510134567 A CN201510134567 A CN 201510134567A CN 104847406 B CN104847406 B CN 104847406B
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- Prior art keywords
- filled wall
- face
- coal
- wall
- filled
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- 239000003245 coal Substances 0.000 title claims abstract description 20
- 238000000034 method Methods 0.000 title claims abstract description 13
- 230000000717 retained effect Effects 0.000 title abstract description 7
- 238000005065 mining Methods 0.000 claims abstract description 17
- 239000002360 explosive Substances 0.000 claims abstract description 7
- 239000002002 slurry Substances 0.000 claims abstract description 7
- 238000010276 construction Methods 0.000 claims abstract description 5
- 238000005553 drilling Methods 0.000 claims description 17
- 239000000843 powder Substances 0.000 claims description 13
- 230000003068 static effect Effects 0.000 claims description 11
- 239000003795 chemical substances by application Substances 0.000 claims description 10
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 7
- 230000003111 delayed effect Effects 0.000 claims description 5
- 229920005830 Polyurethane Foam Polymers 0.000 claims description 4
- 239000011496 polyurethane foam Substances 0.000 claims description 4
- 238000002360 preparation method Methods 0.000 claims description 4
- 238000007789 sealing Methods 0.000 claims description 4
- 238000005336 cracking Methods 0.000 claims description 3
- 239000007788 liquid Substances 0.000 claims description 2
- 239000000203 mixture Substances 0.000 claims description 2
- 238000004519 manufacturing process Methods 0.000 description 5
- 239000004568 cement Substances 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 230000002787 reinforcement Effects 0.000 description 2
- 208000037656 Respiratory Sounds Diseases 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000006378 damage Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 239000002674 ointment Substances 0.000 description 1
- 230000008961 swelling Effects 0.000 description 1
- 239000002912 waste gas Substances 0.000 description 1
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
- E21F15/00—Methods or devices for placing filling-up materials in underground workings
- E21F15/02—Supporting means, e.g. shuttering, for filling-up materials
- E21F15/04—Stowing mats; Goaf wire netting; Partition walls
Landscapes
- Engineering & Computer Science (AREA)
- Mining & Mineral Resources (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)
- Excavating Of Shafts Or Tunnels (AREA)
Abstract
Disclosed is a method for fracturing a retained filled wall of an adjacent coal face. The method is applicable to continuous pressure relief mining of deep coal seam groups. The method comprises the steps that the arrangement mode and parameters of drilled holes and the explosive load are designed according to the size, the construction mode and the earlier-stage breakage state of the filled wall; one to three rows of downwards-inclined reused drilled holes for construction of the filled wall are retained by a leading coal face for the adjacent coal face in a roadway; one to two columns of drilled holes which are formed in the rear portion of the interior of an end hydraulic support are filled with slurry and explosives and are sealed; and the drilled holes which are formed in the rear portion of the interior of the end hydraulic support and filled with the explosives enter the position behind the coal face along with propulsion of the coal face, fracturing of the filled wall is enhanced through microcracks generated by the earlier-stage mine pressure of the filled wall, and finally the retained filled wall is fractured through the combination between the microcracks and the lagged mining-induced stress influence. According to the invention, the filled wall retained by the adjacent coal face in goaf can be fractured, and therefore the influence of the filled wall on stress concentration in an upper adjacent coal seam and a lower adjacent coal seam is effectively eliminated, the purpose of continuous pressure relief is achieved, and the potential safety hazard of adjacent coal seam mining is eliminated.
Description
Technical field
The present invention relates to the method that a kind of adjacent coal-face of fracturing leaves filled wall, is particularly suited for deep fractures
The continuous Depressurized mining of group.
Background technology
Gob side entry retaining is to construct the body of wall with certain bearing capacity along mined out area edge, by adjacent coal-face back production
Tunnel remains, and uses as the back production of this coal-face.It is the continuous Depressurized mining of deep fractures group key technology it
One, for solving the safety difficulties such as impulsion pressure, coal and gas prominent, high methane, highland pressure.
Gob side entry retaining body of wall is constructed using cement base class material at present more and more universal, especially deep mining area.Cement based
The rapid hardening of class body of wall is early strong, is aided with the reinforcement means such as shear anchor arm, three-dimensional reinforcement, ensure that substantially two coal-faces are returned
Adopt tunnel normally to use.Although cement base class body of wall is by the germinating microfissure of mining influence twice, but still persistently increase resistance, can not be certainly
Destruction load-carrying properties, in upper and lower adjacent coal seam define stress-concentrated area, do not reach the purpose of continuous release, remain neighbouring
The potential safety hazard of seam mining.Therefore, at present in the urgent need to providing a kind of method, in the back production of this coal-face, aggravation is caused
The filled wall that adjacent coal-face is retained in goaf is split, its bearing capacity is destroyed.
The content of the invention
Technical problem：The purpose of the present invention is to overcome the shortcomings of prior art, there is provided a kind of adjacent coal work of fracturing
The method that filled wall is left in face.
Technical scheme：The method that the adjacent coal-face of fracturing of the present invention leaves filled wall is as follows：
A, according to filled wall size, construct mode and early stage breakage state, design bore arrangement mode and parameter, powder charge
Amount；
B, advanced coal-face, filled wall 1 ~ 3 row of construction for retaining multiplexing to adjacent coal-face in lane incline
Under tiltedly to drilling；
C, coal mining, charging are synchronously carried out, and powder charge step pitch is not more than the passage step pitch of end hydraulic support, to termination liquid
1 ~ 2 row well cementing powder charge at rear in pressure support frame；The grouting slurry mixes water by SCA- I or II type static fracturing agents of SCA-
Make, drilling orifice carries out sealing of hole with yellow mud or polyurethane foam；
D, with the propulsion of coal-face, in end hydraulic support frame, rear powder charge drills into coal-face
Rear, produces the bulbs of pressure after 3 ~ 8h, press the microfissure of germinating, aggravation filled wall cracking, knot using filled wall early stage ore deposit
Closing delayed mining induced stress affects, and leaves filled wall finished breaking；
E, repeat step b, c, until completing the adjacent coal-face of fracturing leaves filled wall.
Under the inclination to bore inclining angle be 10 ~ 25 °, aperture be 40 ~ 100mm, pitch-row be 0.4 ~ 0.8m, array pitch
For 0.3 ~ 0.7m, away from top, 0.5 ~ 1.0m of base plate, the goaf side of bottom hole pitch filled wall is 20 ~ 30cm to eyelet.
The water preparation ratio of the grouting slurry is 0.25 ~ 0.35, and the explosive payload of unit volume filled wall static breaking agent is
10~25kg。
Beneficial effect：As a result of above-mentioned technical proposal, the present invention is compared with prior art：Effect is good, low cost, behaviour
Make simple, it is safe and reliable.Concrete advantage is as follows：
1）Static fracturing agents expand great efforts, press the microfissure of germinating using filled wall early stage ore deposit, and aggravation fracturing is adjacent
Coal-face is retained in the filled wall in goaf, and with reference to the effect of delayed mining induced stress, makes filled wall finished breaking.
Overlying strata fully can sink, and effectively eliminating body of wall affects on the stress concentration in upper and lower adjacent coal seam, realizes continuous release
Purpose, solve adjacent coal seam exploitation potential safety hazard.
2）During Static crushing, slungshot, dust, waste gas are not produced, safety coefficient is high.
3）Advance borehole inclines 10 ~ 25 °, is easy to workman's operation, and part make use of body of wall easily generation crisp along 45 ° of oblique sections
The characteristic of property tensile failure, is effectively saved crushing power, reduces broken cost.
4）Operation in the advanced coal-face of workman or end hydraulic support frame, job safety.
5）Operation is simple, convenient to operate, and workman's operation intensity is low, and the activity duration is few.
Description of the drawings
Schematic top plan view when Fig. 1 is the coal-face back production of the present invention；
Fig. 2 is drilling arrangement schematic diagram near the end hydraulic support of the present invention；
Fig. 3 is the wall body hole cross-sectional schematic of the present invention.
In figure：1- filled walls；2- drills；3- coal-faces；The adjacent coal-faces of 4-；5- static fracturing agents；6-
End hydraulic support；7- yellow mud or polyurethane foam.
Specific embodiment
Below in conjunction with the accompanying drawings one embodiment of the present of invention is further described：
The method that the adjacent coal-face of fracturing of the present invention leaves filled wall, comprises the following steps that：
A, according to 1 size of filled wall, construct mode and early stage breakage state, design drilling 2 arrangements and parameter, dress
Dose；
B, advanced coal-face, retain 1 ~ 3 row of construction of filled wall 1 of multiplexing in lane to adjacent coal-face 4
Under inclination to drilling 2；Under the inclination to 2 angle of inclination of drilling be 10 ~ 25 °, aperture be 40 ~ 100mm, pitch-row be 0.4 ~
0.8m, array pitch is 0.3 ~ 0.7m, eyelet away from top, 0.5 ~ 1.0m of base plate, the goaf side of bottom hole pitch filled wall 1 is 20 ~
30cm。
C, coal mining, charging are synchronously carried out, and powder charge step pitch is not more than the passage step pitch of end hydraulic support 6, to termination
1 ~ 2 row drilling, the 2 grouting powder charge at rear in 6 frame of hydraulic support；The grouting slurry is by II type static fracturing agents of SCA- I or SCA-
5 mix water makes, and drilling orifice carries out sealing of hole with yellow mud or polyurethane foam 7；It is described grouting slurry water preparation ratio be 0.25 ~
0.35, the explosive payload of 1 static breaking agent 5 of unit volume filled wall is 10 ~ 25kg.
D, with the propulsion of coal-face 3, the drilling 2 of rear powder charge in 6 frame of end hydraulic support enters coal-getter
Make 3 rear of face, after 3 ~ 8h, produce the bulbs of pressure, the microfissure of germinating is pressed using 1 early stage ore deposit of filled wall, aggravate filled wall
（1）Cracking, affects with reference to delayed mining induced stress, leaves 1 finished breaking of filled wall；
E, repeat step b, c, until completing the adjacent coal-face of fracturing leaves filled wall.
The adjacent coal-face 4 of embodiment 1, certain ore deposit retains 1 width of the filled wall × height=3m × 2.6m of multiplexing, using pump
Send C30 ointment materials to construct, and be aided with shear anchor arm.During 3 back production of this coal-face, stress concentration peak value occurs in advanced work
Make face 13m, up to 1.67, nearby 1 total quality of filled wall is good herein for the factor of stress concentration, and a small amount of crackle occurs in surface.
Advanced coal-face 3 apart from 30m, 2 rows that construct to filled wall 1 in lane incline under to drilling 2, angle of inclination
15 °, aperture 50mm, pitch-row 0.6m, array pitch 0.6m, away from top board 1.0m, away from base plate 1.0m, bottom hole pitch filled wall 1 is another for eyelet
Side 25cm.
Mine, charging is synchronously carried out.It is not more than the original of the passage step pitch of end hydraulic support 6 according to powder charge step pitch
Then, passage step pitch 0.6m of end hydraulic support 6, it is determined that the 1 row well cementing powder charge to rear in 6 frame of end hydraulic support.
Using II type static fracturing agents 5 of SCA-, than 0.3 or so, aperture stays about 10cm yellow mud 7 to carry out sealing of hole to water preparation.Unit volume is filled
Fill out the 10 ~ 25kg of explosive payload of 1 static breaking agent 5 of body of wall.
With the propulsion of coal-face 3, the drilling 2 of powder charge enters 3 rear of coal-face, produces swollen after 3 ~ 8h
Swelling pressure power, presses the microfissure of germinating, aggravation filled wall 1 to ftracture using 1 early stage ore deposit of filled wall.With reference to delayed mining induced stress shadow
Ring, leave 1 finished breaking of filled wall.
Claims (3)
1. the method that a kind of adjacent coal-face of fracturing leaves filled wall, it is characterised in that comprise the steps：
A, according to filled wall（1）Size, construct mode and early stage breakage state, design drilling（2）Arrangement and parameter, dress
Dose；
B, advanced coal-face, to adjacent coal-face in lane（4）Retain the filled wall of multiplexing（1）1 ~ 3 row of construction
Under inclination to drilling（2）；
C, coal mining, charging are synchronously carried out, and powder charge step pitch is not more than end hydraulic support（6）Passage step pitch, to termination liquid
Pressure support（6）1 ~ 2 row drilling at rear in frame（2）Grouting powder charge；The grouting slurry is by II type Static crushing of SCA- I or SCA-
Agent（5）Mix water to make, drilling orifice yellow mud or polyurethane foam（7）Carry out sealing of hole；
D, with coal-face（3）Propulsion, end hydraulic support（6）The drilling of rear powder charge in frame（2）Into coal mining
Work surface（3）Rear, produces the bulbs of pressure, using filled wall after 3 ~ 8h（1）The microfissure of early stage ore deposit pressure germinating, aggravation filling
Body of wall（1）Cracking, affects with reference to delayed mining induced stress, leaves filled wall（1）Finished breaking；
E, repeat step b, c, until completing the adjacent coal-face of fracturing leaves filled wall.
2. the method that the adjacent coal-face of fracturing according to claim 1 leaves filled wall, it is characterised in that：It is described
Drilling（2）Angle of inclination be 10 ~ 25 °, aperture be 40 ~ 100mm, pitch-row be 0.4 ~ 0.8m, array pitch be 0.3 ~ 0.7m, eyelet away from
Top, 0.5 ~ 1.0m of base plate, bottom hole pitch filled wall（1）Goaf side be 20 ~ 30cm.
3. the method that the adjacent coal-face of fracturing according to claim 1 leaves filled wall, it is characterised in that：It is described
The water preparation ratio of grouting slurry is 0.25 ~ 0.35, unit volume filled wall（1）Static breaking agent（5）Explosive payload be 10 ~
25kg。
Priority Applications (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510134567.2A CN104847406B (en) | 2015-03-25 | 2015-03-25 | Method for fracturing retained filled wall of adjacent coal face |
| AU2015387618A AU2015387618B2 (en) | 2015-03-25 | 2015-11-30 | Method for fracturing filler wall left behind in adjacent coal-mining face |
| PCT/CN2015/095914 WO2016150188A1 (en) | 2015-03-25 | 2015-11-30 | Method for fracturing filler wall left behind in adjacent coal-mining face |
| ZA2017/01756A ZA201701756B (en) | 2015-03-25 | 2017-03-10 | Method for fracturing filler wall left behind in adjacent coal-mining face |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510134567.2A CN104847406B (en) | 2015-03-25 | 2015-03-25 | Method for fracturing retained filled wall of adjacent coal face |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN104847406A CN104847406A (en) | 2015-08-19 |
| CN104847406B true CN104847406B (en) | 2017-04-12 |
Family
ID=53847331
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510134567.2A Active CN104847406B (en) | 2015-03-25 | 2015-03-25 | Method for fracturing retained filled wall of adjacent coal face |
Country Status (4)
| Country | Link |
|---|---|
| CN (1) | CN104847406B (en) |
| AU (1) | AU2015387618B2 (en) |
| WO (1) | WO2016150188A1 (en) |
| ZA (1) | ZA201701756B (en) |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104847406B (en) * | 2015-03-25 | 2017-04-12 | 中国矿业大学 | Method for fracturing retained filled wall of adjacent coal face |
| CN106761543B (en) * | 2016-12-02 | 2019-07-19 | 淮北矿业股份有限公司 | A method of drilling misses section by goaf |
| CN107035370A (en) * | 2017-05-05 | 2017-08-11 | 太原理工大学 | One kind cuts top pressure relief method for gob side entry retaining static crushing |
| CN109252891B (en) * | 2018-11-05 | 2023-09-19 | 徐州中矿大贝克福尔科技股份有限公司 | Paste filling continuous flexible sealing device and isolation method |
| CN110761792B (en) * | 2019-12-02 | 2023-05-16 | 六盘水师范学院 | Overold cutting device for coal face and application method |
| CN113153299B (en) * | 2021-05-11 | 2024-04-30 | 四川川煤华荣能源有限责任公司 | Microwave directional roof-cutting pressure-relief gob-side entry retaining method |
| CN113217093B (en) * | 2021-06-21 | 2024-04-16 | 扬州中矿建筑新材料科技有限公司 | Foldable framework film bag filling wall/body for gob-side entry retaining and construction method |
| CN114856567A (en) * | 2022-05-16 | 2022-08-05 | 中国矿业大学(北京) | Method for determining layout position of coal seam mining roadway under short-distance variable-interval condition |
Family Cites Families (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4059963A (en) * | 1976-08-19 | 1977-11-29 | Joy Manufacturing Company | Method of mine backfilling and material therefor |
| DE19915939B4 (en) * | 1999-04-09 | 2008-02-28 | Udo Adam Maschinenfabrik | Dammbaubock with adjustable shuttering walls |
| RU2283431C1 (en) * | 2005-04-28 | 2006-09-10 | Государственное образовательное учреждение высшего профессионального образования СИБИРСКИЙ ГОСУДАРСТВЕННЫЙ ИНДУСТРИАЛЬНЫЙ УНИВЕРСИТЕТ | Method for thick steep mineral seam mining along with goaf filling |
| CN101725352B (en) * | 2009-12-04 | 2012-03-07 | 中国矿业大学 | Method for filling solid and fully mechanizing and recovering room type coal pillar |
| CN201568083U (en) * | 2009-12-24 | 2010-09-01 | 攀枝花煤业（集团）有限责任公司 | Gob-side entry retaining filling wall structure |
| CN103046955A (en) * | 2012-12-24 | 2013-04-17 | 河北钢铁集团矿业有限公司 | Large-range goaf group filling method |
| CN102979572B (en) * | 2012-12-26 | 2015-07-08 | 宏大矿业有限公司 | Active reinforced filling wall and construction method |
| CN103075127B (en) * | 2012-12-27 | 2016-02-24 | 中国矿业大学 | A kind of flexible filling material drilling and sealing device and method |
| CN103527196B (en) * | 2013-10-28 | 2015-07-01 | 中国矿业大学 | Method for recovery of room-type coal pillar through loess filling |
| CN103939135B (en) * | 2014-05-07 | 2016-03-02 | 中国矿业大学 | A kind of fully-mechanized mining working removes frame passage rapid constructing method |
| CN104005786B (en) * | 2014-05-30 | 2016-05-11 | 烟台大学 | For the cast-in-place foamed partition wall construction method of tailing-filled mining |
| CN104847406B (en) * | 2015-03-25 | 2017-04-12 | 中国矿业大学 | Method for fracturing retained filled wall of adjacent coal face |
-
2015
- 2015-03-25 CN CN201510134567.2A patent/CN104847406B/en active Active
- 2015-11-30 AU AU2015387618A patent/AU2015387618B2/en not_active Ceased
- 2015-11-30 WO PCT/CN2015/095914 patent/WO2016150188A1/en active Application Filing
-
2017
- 2017-03-10 ZA ZA2017/01756A patent/ZA201701756B/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| CN104847406A (en) | 2015-08-19 |
| AU2015387618B2 (en) | 2018-11-01 |
| ZA201701756B (en) | 2019-06-26 |
| AU2015387618A1 (en) | 2017-07-06 |
| WO2016150188A1 (en) | 2016-09-29 |
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Address after: 221116 Research Institute of China University of Mining and Technology,, Jiangsu Applicant after: China University of Mining & Technology Address before: 221116 Research Institute, China University of Mining and Technology, Xuzhou University, Jiangsu, China, Applicant before: China University of Mining & Technology |
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Inventor after: Pan Dongjiang Inventor after: Zhang Nong Inventor after: Lv Chuangxin Inventor after: Han Changliang Inventor after: Xue Fei Inventor before: Zhang Nong Inventor before: Pan Dongjiang Inventor before: Lv Chuangxin Inventor before: Han Changliang Inventor before: Xue Fei |
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