CN112483174A - Arrangement method of tunneling working face impact dangerous vibration wave CT inversion system - Google Patents
Arrangement method of tunneling working face impact dangerous vibration wave CT inversion system Download PDFInfo
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- 238000000034 method Methods 0.000 title claims abstract description 32
- 230000005641 tunneling Effects 0.000 title claims abstract description 25
- 239000003245 coal Substances 0.000 claims abstract description 37
- 239000011435 rock Substances 0.000 claims abstract description 22
- 238000012544 monitoring process Methods 0.000 claims abstract description 17
- 238000011161 development Methods 0.000 claims abstract description 9
- 238000005065 mining Methods 0.000 claims description 9
- 238000004458 analytical method Methods 0.000 claims description 3
- 238000011156 evaluation Methods 0.000 claims description 3
- 238000009412 basement excavation Methods 0.000 claims description 2
- 230000035939 shock Effects 0.000 claims 4
- 230000002265 prevention Effects 0.000 abstract description 6
- 230000003068 static effect Effects 0.000 description 8
- 238000010586 diagram Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 1
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- 238000005516 engineering process Methods 0.000 description 1
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- 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
- E21F17/00—Methods or devices for use in mines or tunnels, not covered elsewhere
- E21F17/18—Special adaptations of signalling or alarm devices
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
- G01V1/00—Seismology; Seismic or acoustic prospecting or detecting
- G01V1/28—Processing seismic data, e.g. for interpretation or for event detection
- G01V1/282—Application of seismic models, synthetic seismograms
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
- G01V1/00—Seismology; Seismic or acoustic prospecting or detecting
- G01V1/28—Processing seismic data, e.g. for interpretation or for event detection
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Abstract
The invention discloses an arrangement method of a tunneling working face impact dangerous vibration wave CT inversion system, which comprises the steps of firstly determining the grade and the range of an impact dangerous area in a to-be-tunneled area; then determining the position of a newly dug coal roadway in front of the impact dangerous area along the development direction of the developed large roadway; then respectively arranging a plurality of seismic picking sensors in a newly excavated roadway, an expanded roadway and an excavated roadway to form effective enclosure of an impact dangerous area to be excavated; collecting mine earthquake waveforms of a driving working face and an adjacent stope working face; and establishing a vibration wave CT inversion model in the monitoring range, performing vibration wave velocity CT inversion of the impact dangerous area by adopting a known inversion algorithm, and dividing grades of different positions in the impact dangerous area based on the impact dangerous early warning model so as to realize early warning work. The invention improves the monitoring and early warning efficiency of the impact danger of the driving face in the impact dangerous area and effectively guides the rock burst prevention and control of the driving face.
Description
Technical Field
The invention relates to an arrangement method of a tunneling working face impact dangerous vibration wave CT inversion system, and belongs to the technical field of coal mine safety production.
Background
With the increase of the mining depth of coal resources, the stress state of coal mine tunnels, particularly surrounding rocks of coal seam tunnels, is continuously deteriorated, dynamic disasters such as ore pressure impact and the like are more frequent in the tunneling process of the tunnels, and the safe and efficient production of coal mines is seriously restricted. Research shows that the rock burst generation is a result of superposition and combined action of dynamic load and static load, the impact degrees of the static load and the dynamic load are different for the rock burst of different buried coal beds, wherein the deep mining rock burst belongs to high static load type rock burst, the static load of surrounding rocks is higher, and the superposition load can exceed a critical value by a tiny dynamic load increment generated by mine earthquake to further induce coal rock impact damage, so that the monitoring and early warning of the static load stress of the surrounding rocks are of great importance to the rock burst prevention and control of deep impact dangerous tunneling working faces.
The traditional method for monitoring the static load stress of the surrounding rock mainly comprises the following steps: drilling cutting method, stress on-line, Passat monitoring and the like, but due to the small monitoring range, large labor intensity and the like, the effective, rapid and accurate monitoring of the surrounding rock stress field is difficult to realize. Based on the correlation between the stress and the wave velocity of the surrounding rock, the seismic wave CT inversion technology is widely applied to monitoring and early warning of the static load stress of the surrounding rock in a coal mine stope due to low labor intensity, high efficiency and wide monitoring range. However, for the tunneling working face, the tunneling working face is usually located at the front end of the well field development direction and is limited by space, and the existing mine vibration pickup sensor arrangement mode is difficult to form effective enclosure on the tunneling working face, so that the monitoring and early warning efficiency of the static load stress of the surrounding rock of the tunneling working face is low, and the rock burst prevention and control of the tunneling working face with impact risks, especially with strong impact risks, cannot be effectively guided. Therefore, how to provide an arrangement method can effectively surround the formation of the tunneling working face with strong impact danger, so that the impact danger monitoring and early warning efficiency of the tunneling working face with the strong impact danger is improved, and the rock burst prevention and treatment of the tunneling working face is effectively guided, and the method is a research direction of the industry.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides an arrangement method of a tunneling working face impact dangerous vibration wave CT inversion system, which is characterized in that effective enclosure of a strong impact dangerous tunneling working face is formed by optimizing the table network arrangement of the vibration wave CT inversion system, so that the impact dangerous monitoring and early warning efficiency of the strong impact dangerous tunneling working face on the impact dangerous area is improved, and the rock burst prevention and control of the tunneling working face are effectively guided.
In order to achieve the purpose, the invention adopts the technical scheme that: a method for arranging an impulse dangerous vibration wave CT inversion system of a driving face comprises the following specific steps:
firstly, determining impact danger grade and range
Determining the grade and the range of an impact danger area in an excavation and to-be-excavated area by utilizing a known coal mine impact danger evaluation method (such as a comprehensive index method) and fully considering factors of coal bed buried depth, faults, fold, rock stratum structure and coal thickness change;
constructing new coal road and laying vibration pick-up sensor
Determining the position of a newly dug coal roadway in front of an impact dangerous area along the development direction of a developed large roadway, and then constructing the newly dug coal roadway at the position and enabling the trend of the newly dug coal roadway to be parallel to the trend of the dug coal roadway; then respectively arranging a plurality of seismic picking sensors in a newly excavated roadway, an expanded roadway and an excavated roadway which is closest to the newly excavated roadway behind the high impact danger range to form effective enclosure of an impact danger area to be excavated;
thirdly, inverse analysis of impact danger of driving face
The method comprises the steps of acquiring mine earthquake waveforms of a driving face and an adjacent mining face around an impact dangerous area in real time through each earthquake pickup sensor, establishing a vibration wave CT inversion model in a monitoring range, performing vibration wave velocity CT inversion of the impact dangerous area by adopting a known inversion algorithm, obtaining wave velocity values of all points in the inversion area, a wave velocity average value and ray density in the inversion area, determining an inversion reliable area according to the ray density, and performing real-time early warning on impact dangerous grades at different positions in the inversion reliable area in the working process of the driving face on the basis of an impact dangerous early warning model.
Further, the lengths of the newly dug coal roadway and the dug roadway exceed the length of the impact danger area in the direction of the dug roadway.
And further, in the second step, the distance between adjacent seismic sensors in the newly excavated roadway, the developed large roadway and the excavated roadway is 100-200 m.
Further, in the third step, a seismic wave CT inversion model is established by adopting a self-adaptive unequal-interval grid division method, wherein the node interval in the seismic source concentrated region is 10m, and the node interval outside the seismic source concentrated region is 20 m; the inversion algorithm is a simultaneous iterative reconstruction method.
Further, the impact risk early warning model in the third step is as follows:
wave velocity anomaly coefficient
In the formula: vpThe value of the longitudinal wave velocity of any point in the inversion region,
the average value of the wave velocity in the inversion region is obtained;
Anrelation to impact hazard
Furthermore, the inversion reliable area in the third step is an area with the ray density larger than 10.
Compared with the prior art, the method determines the grade and the range of the impact dangerous area in the area to be excavated; then determining the position of a newly dug coal roadway in front of the impact dangerous area along the development direction of the developed large roadway; then respectively arranging a plurality of seismic picking sensors in a newly excavated roadway, an expanded roadway and an excavated roadway which is closest to the newly excavated roadway behind the high impact danger range to form effective enclosure of an impact danger area to be excavated; collecting mine earthquake waveforms of a tunneling working face and an adjacent stope working face around an impact dangerous area; and establishing a vibration wave CT inversion model in the monitoring range, performing vibration wave velocity CT inversion of the impact dangerous area by adopting a known inversion algorithm, and then dividing grades of different positions in the impact dangerous area of the tunneling working face based on the impact dangerous early warning model so as to realize early warning work. According to the invention, effective surrounding of the tunneling working face with strong impact danger is formed by optimizing the table network arrangement of the vibration wave CT inversion system, so that the impact danger monitoring and early warning efficiency of the tunneling working face in an impact danger area is improved, and the rock burst prevention and control of the tunneling working face are effectively guided.
Drawings
FIG. 1 is a schematic view of a mining plan for a mine;
FIG. 2 is a schematic view of an impact hazard zone identified by the present invention;
FIG. 3 is a schematic diagram of the position layout of the seismic pick-up sensors in the present invention;
FIG. 4 is a schematic diagram of the present invention for performing seismic wave CT inversion of impact hazard zones.
Wherein, 1, a large roadway is developed; 2. designing a mining stopping line on a working face; 3. digging a roadway; 4. designing a roadway to be excavated; 5. impacting the hazard area; 6. newly digging a coal roadway; 7. a seismic pick-up sensor; 8. a gob; 9. a mine earthquake focus; 10. ore earthquake rays; 11. and (6) inverting the reliable area.
Detailed Description
The present invention will be further explained below.
As shown in fig. 1, the development direction of the development roadway 1 in fig. 1 is taken as the front direction for description, and the specific steps of the invention are as follows:
firstly, determining impact danger grade and range
Determining the grade and the range of an impact dangerous area 5 in the mining and to-be-mined area by utilizing a known coal mine impact danger evaluation method (such as a comprehensive index method) and fully considering factors of coal bed buried depth, faults, fold, rock stratum structure and coal thickness change; as shown in fig. 2;
constructing a new coal tunnel 6 and arranging a vibration pickup sensor 7
Determining the position of a new coal driving lane 6 in front of the impact dangerous area 5 along the development direction of the development main lane 1, and then constructing the new coal driving lane 6 at the position and enabling the trend of the new coal driving lane 6 to be parallel to the trend of the already-driven lane 3; then respectively arranging a plurality of seismic sensors 7 in a newly excavated roadway 6, an expanded roadway 1 and an excavated roadway 3 which is closest to the newly excavated roadway 3 behind the high impact danger range to form effective enclosure of an impact danger area to be excavated; as shown in fig. 3;
thirdly, inverse analysis of impact danger of driving face
The method comprises the steps of acquiring mine earthquake waveforms of a driving face and an adjacent mining face around an impact dangerous area 5 in real time through each earthquake picking sensor 7, establishing a vibration wave CT inversion model in a monitoring range, performing vibration wave velocity CT inversion of the impact dangerous area 5 by adopting a known inversion algorithm, obtaining wave velocity values of all points in an inversion area, a wave velocity average value and ray density in the inversion area, determining an area with the ray density being more than 10 as an inversion reliable area 11, and performing real-time early warning on impact dangerous grades at different positions in the inversion reliable area 11 in the working process of the driving face based on an impact dangerous early warning model.
Further, in the step two, the lengths of the newly dug coal roadway 6 and the dug roadway 3 exceed the length of the impact danger area 5 in the direction of the dug roadway.
Further, in the second step, the distances between adjacent seismic sensors 7 in the newly excavated roadway 6, the developed main roadway 1 and the excavated roadway 3 are all 100-200 m.
Further, in the third step, a seismic wave CT inversion model is established by adopting a self-adaptive unequal-interval grid division method, wherein the node interval in the seismic source concentrated region is 10m, and the node interval outside the seismic source concentrated region is 20 m; the inversion algorithm is a simultaneous iterative reconstruction method.
Further, the impact risk early warning model in the third step is as follows:
wave velocity anomaly coefficient
In the formula: vpThe value of the longitudinal wave velocity of any point in the inversion region,
the average value of the wave velocity in the inversion region is obtained;
Anrelation to impact hazard
Claims (6)
1. A method for arranging an impulse dangerous vibration wave CT inversion system of a driving face is characterized by comprising the following specific steps:
firstly, determining impact danger grade and range
Determining the grade and the range of an impact dangerous area in the mining and to-be-mined area by utilizing a known coal mine impact danger evaluation method and fully considering factors of coal bed buried depth, fault, fold, rock stratum structure and coal thickness change;
constructing new coal road and laying vibration pick-up sensor
Determining the position of a newly dug coal roadway in front of an impact dangerous area along the development direction of a developed large roadway, and then constructing the newly dug coal roadway at the position and enabling the trend of the newly dug coal roadway to be parallel to the trend of the dug coal roadway; then respectively arranging a plurality of seismic picking sensors in a newly excavated roadway, an expanded roadway and an excavated roadway which is closest to the newly excavated roadway behind the high impact danger range to form effective enclosure of an impact danger area to be excavated;
thirdly, inverse analysis of impact danger of driving face
The method comprises the steps of acquiring mine earthquake waveforms of a driving face and an adjacent mining face around an impact dangerous area in real time through each earthquake pickup sensor, establishing a vibration wave CT inversion model in a monitoring range, performing vibration wave velocity CT inversion of the impact dangerous area by adopting a known inversion algorithm, obtaining wave velocity values of all points in the inversion area, a wave velocity average value and ray density in the inversion area, determining an inversion reliable area according to the ray density, and performing real-time early warning on impact dangerous grades at different positions in the inversion reliable area in the working process of the driving face on the basis of an impact dangerous early warning model.
2. The arrangement method of the excavation face impact dangerous vibration wave CT inversion system as claimed in claim 1, wherein the lengths of the newly excavated coal roadway and the excavated roadway exceed the length of the impact dangerous area in the direction of the excavated roadway in the step two.
3. The arrangement method of the impulse dangerous vibration wave CT inversion system of the driving face according to claim 1, wherein the distance between adjacent seismic sensors in a newly excavated roadway, an expanded roadway and an excavated roadway is 100-200 m.
4. The arrangement method of the CT inversion system for the shock hazard shock waves of the driving face according to claim 1, wherein in the third step, the CT inversion model of the shock waves is established by adopting a self-adaptive unequal-interval grid division method, wherein the interval of nodes in a seismic source concentration area is 10m, and the interval of nodes outside the seismic source concentration area is 20 m; the inversion algorithm is a simultaneous iterative reconstruction method.
5. The arrangement method of the tunneling working face impact hazard shock wave CT inversion system according to claim 1, wherein the impact hazard early warning model in the third step is as follows:
wave velocity anomaly coefficient
In the formula: vpThe value of the longitudinal wave velocity of any point in the inversion region,
the average value of the wave velocity in the inversion region is obtained;
Anrelation to impact hazard
6. The arrangement method of the tunneling working face impact dangerous vibration wave CT inversion system according to claim 1, wherein the inversion reliable region in the third step is a region with ray density larger than 10.
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113847093A (en) * | 2021-10-22 | 2021-12-28 | 江苏徐矿能源股份有限公司张双楼煤矿 | Rock burst prevention and control method |
| CN114412570A (en) * | 2022-01-10 | 2022-04-29 | 中国矿业大学 | Rock burst monitoring and early warning method and device based on mobile CT radiation |
| CN114704329A (en) * | 2022-03-17 | 2022-07-05 | 徐州弘毅科技发展有限公司 | Method for monitoring seismic waves and rapidly detecting advanced stress of deep roadway driving mine |
| CN115267900A (en) * | 2022-08-16 | 2022-11-01 | 中国矿业大学 | Method for screening seismic source data by seismic wave CT inversion |
| CN116794725A (en) * | 2023-06-26 | 2023-09-22 | 华亭煤业集团有限责任公司 | Method for correcting impact dangerous area division during stoping based on tunneling microseismic data |
| CN115267900B (en) * | 2022-08-16 | 2024-10-25 | 中国矿业大学 | Screening method for vibration wave CT inversion seismic source data |
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113847093A (en) * | 2021-10-22 | 2021-12-28 | 江苏徐矿能源股份有限公司张双楼煤矿 | Rock burst prevention and control method |
| CN114412570A (en) * | 2022-01-10 | 2022-04-29 | 中国矿业大学 | Rock burst monitoring and early warning method and device based on mobile CT radiation |
| CN114412570B (en) * | 2022-01-10 | 2023-03-07 | 中国矿业大学 | Rock burst monitoring and early warning method and device based on mobile CT radiation |
| CN114704329A (en) * | 2022-03-17 | 2022-07-05 | 徐州弘毅科技发展有限公司 | Method for monitoring seismic waves and rapidly detecting advanced stress of deep roadway driving mine |
| CN114704329B (en) * | 2022-03-17 | 2024-07-26 | 徐州弘毅科技发展有限公司 | Method for monitoring earthquake waves of deep tunnel tunneling mine and rapidly detecting advanced stress |
| CN115267900A (en) * | 2022-08-16 | 2022-11-01 | 中国矿业大学 | Method for screening seismic source data by seismic wave CT inversion |
| CN115267900B (en) * | 2022-08-16 | 2024-10-25 | 中国矿业大学 | Screening method for vibration wave CT inversion seismic source data |
| CN116794725A (en) * | 2023-06-26 | 2023-09-22 | 华亭煤业集团有限责任公司 | Method for correcting impact dangerous area division during stoping based on tunneling microseismic data |
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Application publication date: 20210312 |