CN-122016525-A - Method for detecting directional pre-splitting effect of bidirectional energy-gathering stretch-draw blasting of self-forming roadway roof without coal pillar

CN122016525ACN 122016525 ACN122016525 ACN 122016525ACN-122016525-A

Abstract

The invention relates to the technical field of coal mine non-pillar mining, and discloses a method for detecting the directional pre-splitting effect of bi-directional energy-gathering stretch-draw blasting of a non-pillar self-forming roadway roof, which comprises the following steps that S1, directional pre-splitting drill holes for bi-directional energy-gathering stretch-draw blasting are drilled on the roof at the position of a stoping roadway of a coal face; S2, selecting a directional pre-cracking drilling hole for detection and numbering, S3, completing assembly of a detection system for fracture seepage measurement, S4, measuring the primary fracture seepage of the hole wall of the directional pre-cracking drilling hole by adopting the detection system, and recording seepage data of the primary fracture. The invention can more accurately detect the directional pre-splitting effect of the bi-directional energy-gathering stretch-draw blasting of the self-forming roadway roof without coal pillars, thereby providing a basis for further optimizing the parameters of the bi-directional energy-gathering stretch-draw blasting pre-splitting of the self-forming roadway roof without coal pillars, improving the success rate of the pre-splitting of the self-forming roadway roof without coal pillars and avoiding the safety risk caused by poor roof cutting effect.

Inventors

WANG JIONG
MA LEI
WANG SHUAIJIE
WU YONGWEI
LIU YIPENG
Sang Biaowei
LIANG WENZHAO
CAI FENG
CHANG YIWEN
CHEN XING
JIANG JIAN
XU DEHE
MENG XIANGLEI
CHEN ZHOU

Assignees

中国矿业大学(北京)

Dates

Publication Date: 20260512
Application Date: 20260129

Claims (10)

1. The method for detecting the directional pre-splitting effect of the bi-directional energy-gathering stretch-draw blasting of the self-forming roadway roof without the coal pillar is characterized by comprising the following steps: S1, drilling a directional pre-splitting drill hole for bidirectional energy gathering stretch-draw blasting on a top plate at a stoping roadway position of a coal face; s2, selecting a directional pre-splitting drilling hole for detection and numbering; S3, assembling a detection system for fracture seepage measurement; S4, measuring the seepage flow of the primary fracture on the wall of the directional pre-fracture drilling hole by adopting a detection system, and recording the seepage flow data of the primary fracture; s5, performing roof bidirectional energy gathering tensioning directional pre-splitting blasting on the directional pre-splitting drilling hole; S6, performing fracture seepage measurement on the blasted directional pre-cracked drill hole by adopting a method in the step S4, and recording seepage data of the blasted fracture; and S7, determining the bidirectional energy-gathering stretch-draw blasting effect according to the seepage flow data before and after blasting.
2. The method for detecting the directional pre-splitting effect of the bi-directional energy-gathering stretch-draw blasting of the self-forming roadway roof without coal pillar according to claim 1, wherein the detection system in the step S3 comprises a plugging component extending into a directional pre-splitting drill hole, and a penetration power mechanism and a plugging power mechanism for performing seepage measurement; The plugging assembly comprises a top plugging mechanism, a permeation injection mechanism and a bottom plugging mechanism which are sequentially arranged.
3. The method for detecting the directional pre-splitting effect of the bi-directional energy-gathering stretch-break blasting of the self-forming roadway roof without coal pillar according to claim 2, wherein the penetrating power mechanism comprises a first test bench and a booster pump arranged at the top of the first test bench, the input end of the booster pump is connected with a feeding pipe, the output end of the booster pump is connected with a discharging pipe, a pressure gauge I, a pressure control valve, a valve I, an exhaust valve I and a flow meter which are sequentially arranged are arranged on the discharging pipe, the discharging pipe is used for providing a penetrating medium for penetrating detection, the penetrating medium is stable in pressure, the penetrating medium is fixedly connected with the first test bench, and the valve III is arranged on the feeding pipe.
4. The method for detecting the directional pre-splitting effect of the bi-directional energy-gathering stretch-break blasting of the self-forming roadway roof without the coal pillar according to claim 2, wherein the plugging power mechanism comprises a second test bench, a conveying pipe is arranged at the top of the second test bench and used for providing a power medium for plugging for the detection system, the conveying pipe is sequentially provided with a fourth valve, a second pressure gauge, a second valve and a second exhaust valve, and a second bracket connected with the second test bench is fixedly connected with the conveying pipe.
5. The method for detecting the directional pre-splitting effect of the bi-directional energy-gathering stretch-break blasting of the self-forming roadway roof without coal pillars according to claim 2, wherein the top plugging mechanism comprises a first supporting pipe, a first plugging air bag which extends downwards is fixedly sleeved on an outer ring of the supporting pipe, a first connecting lug which is sequentially arranged along the axis direction of the first plugging air bag is fixedly connected with an inner ring of the plugging air bag, a first connecting air pipe which is communicated with the first plugging air bag is fixedly connected with the inner ring of the supporting pipe, and a first butt joint pipe which is in butt joint with the penetrating injection mechanism is sleeved at the bottom of the first connecting air pipe in a sliding manner.
6. The method for detecting the directional pre-splitting effect of the bi-directional energy-gathering stretch-draw blasting of the self-forming roadway roof without coal pillars according to claim 2, wherein the penetrating injection mechanism comprises a second supporting pipe which is in butt joint with the top plugging mechanism, a baffle is fixedly connected with an inner ring at the top of the second supporting pipe, a connecting air pipe is fixedly sleeved on the baffle, a diversion cover shell which is fixedly sleeved with the inner ring of the second supporting pipe is arranged at the bottom of the baffle, a spray hole penetrating through the second supporting pipe is formed in the outer side of the diversion cover shell, and a feeding pipe is arranged in the inner side of the diversion cover shell.
7. The method for detecting the directional pre-splitting effect of the bi-directional energy-gathering stretch-break blasting of the self-forming roadway roof without coal pillars according to claim 2, wherein the bottom plugging mechanism comprises a support tube III which is in butt joint with the penetrating injection mechanism, a plugging air bag II of an annular structure is fixedly sleeved on the outer ring of the top of the support tube III, a connecting lug II distributed along the array of the connecting lug II is fixedly connected with the inner ring of the top of the plugging air bag II, a connecting air tube III is arranged on the inner ring of the support tube III, a butt joint tube II which is in butt joint with the penetrating injection mechanism is sleeved on the top of the connecting air tube III in a sliding mode, and a branch tube communicated with the plugging air bag II is arranged on one side of the connecting air tube III.
8. The method for detecting the directional pre-splitting effect of the bi-directional energy-gathering stretch-draw blasting of the roof of the self-forming roadway without coal pillars according to claim 1, wherein in the step S5, a blasting agent body for pre-splitting blasting is buried in a position set by the directional pre-splitting drilling hole, the directional pre-splitting drilling hole is plugged by using sealing mud at an opening of the directional pre-splitting drilling hole, and then the bi-directional energy-gathering stretch-draw directional pre-splitting blasting of the roof is performed on the directional pre-splitting drilling hole by using the blasting agent body.
9. The method for detecting the directional pre-splitting effect of the bi-directional energy-gathering stretch-break blasting of the self-forming roadway roof without coal pillars according to claim 1 is characterized in that in the step S7, the drilling seepage after blasting is compared with the seepage before blasting, if the drilling seepage after blasting is far greater than the drilling seepage before blasting, the bi-directional energy-gathering stretch-break blasting effect is good, the roof cutting effect is ideal, and in addition, when a large amount of water flows out from adjacent drilling holes of the detected drilling holes, the bi-directional energy-gathering stretch-break blasting effect can be indicated.
10. The method for detecting the directional pre-splitting effect of the bi-directional energy-gathering stretch-draw blasting of the self-forming roadway roof without the coal pillar according to claim 2, wherein the detection system further comprises a control box, a controller is arranged in the control box, and a display screen for displaying the pressure and the flow in the detection process of the detection system is arranged on one side of the control box.

Description

Method for detecting directional pre-splitting effect of bidirectional energy-gathering stretch-draw blasting of self-forming roadway roof without coal pillar Technical Field The invention relates to the technical field of coal mine non-pillar mining, in particular to a method for detecting directional pre-splitting effect of bi-directional energy gathering stretch-draw blasting of a self-forming roadway roof without a pillar. Background Coal is the main energy source of China, and the proportion of coal in the primary energy consumption structure of China is about 57%. The safety production of coal is related to the stability of energy supply and the implementation of energy strategy, is a reliable guarantee for the national economy development, and is a 'ballast stone' for energy safety. The traditional reserved section coal pillar mining technology not only causes serious waste of coal resources, but also causes a series of mine pressure problems and causes adverse effects on ecological environment. The technology is based on the theory of 'roof-cutting short-arm beam' which is explored by the team of the wet courts, and adopts the roof directional pre-splitting slitting technology to actively cut the roof and relieve pressure, and utilizes partial rock mass of the roof to form the roadway side, so as to realize the purpose of canceling coal pillar and roadside filling, achieve the purpose of automatic roadway formation along the sky, and cooperate with the self-developed high-prestress NPR excavation compensation support technology to inhibit surrounding rock deformation, and the anti-impact yielding gangue blocking support technology capable of buffering and resisting load as the core technical system, thereby realizing the technological goals of 'pulling, cutting, getting down and protecting well'. The method is different from the arrangement mode of one-side double-roadway in the traditional long-arm exploitation, only one roadway needs to be driven in to exploit one working surface, the other 1 roadway is automatically formed into a roadway through roof cutting and pressure relief, a protective coal pillar does not need to be reserved, the working surface is changed from 'skip exploitation' into continuous exploitation, periodic pressure of the roadway is effectively reduced, and safety and economic benefits are quite remarkable. In the process of roof cutting and pressure relief of coal pillar-free exploitation, the effect of directional presplitting of roof bidirectional energy-gathering stretch-draw blasting can generate obvious differences on the stress condition of the roof, the mine pressure display rule, the caving condition of the goaf roof and the like, so that the stability of a roadway is influenced, and the roadway forming effect is influenced. The conventional means for detecting the directional presplitting effect of the roof bidirectional energy-gathering stretch-draw blasting in the coal mine is to detect through a drilling peeping instrument, deeply drill holes through a probe, collect hole wall images or videos, transmit data to the ground or terminal equipment, and help to know the conditions of cracks in the drill holes. However, the drill peeping instrument can only observe cracks on the surface of the inner wall of the drill, cannot detect the internal crack conditions, and cannot accurately detect the internal blasting effect. In order to more accurately test and evaluate the effect of directional blasting pre-cracking of the top plate, a method for detecting the effect of directional blasting pre-cracking of the bi-directional energy-gathering tensioning of the top plate of the self-forming roadway without coal pillars is provided. The method detects and compares the permeability change of the wall of the drilling hole before and after the bidirectional stretching pre-cracking, and detects the crack development condition in the drilling hole after the directional blasting, so as to judge the effect of the directional pre-cracking of the top plate. Disclosure of Invention The invention provides a method for detecting directional pre-splitting effect of bi-directional energy gathering stretch-draw blasting of a self-forming roadway roof without coal pillars, aiming at solving the technical problems existing in the prior art. The invention adopts the following technical scheme that the method for detecting the directional presplitting effect of the bi-directional energy-gathering stretch-draw blasting of the self-forming roadway roof without coal pillars comprises the following steps: S1, drilling a directional pre-splitting drill hole for bidirectional energy gathering stretch-draw blasting on a top plate at a stoping roadway position of a coal face; s2, selecting a directional pre-splitting drilling hole for detection and numbering; S3, assembling a detection system for fracture seepage measurement; S4, measuring the seepage flow of the primary fracture on the wall of the dire