CN204214713U - A kind of energetic disturbance induction coal and gas prominent analogue experiment installation - Google Patents
A kind of energetic disturbance induction coal and gas prominent analogue experiment installation Download PDFInfo
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- CN204214713U CN204214713U CN201420456712.XU CN201420456712U CN204214713U CN 204214713 U CN204214713 U CN 204214713U CN 201420456712 U CN201420456712 U CN 201420456712U CN 204214713 U CN204214713 U CN 204214713U
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Abstract
The utility model discloses a kind of energetic disturbance induction coal and gas prominent analogue experiment installation, it comprises experimental box body, the side plate all around (5) of experimental box body, experimental box body top cover (2) and experimental box body base plate (15) composition seal chamber, it is characterized in that: separated by air permeable steel plate (30) in the middle of seal chamber, cavity between experimental box body base plate (15) to air permeable steel plate (30) is analogy model chamber, lifting jack (3) is installed between experimental box body top cover (2) and air permeable steel plate (30), the left side plate of seal chamber is fixed with stress wave conductive bar (13), experimental box body is provided with power charger (7), seal chamber is provided with data detection device, solve prior art induction coal and gas prominent analogue experiment installation not consider to concentrate the disturbance of dynamic load and complex geological condition to cause in far field experimental result is inaccurate effectively to prevent and to administer the problems such as gas.
Description
Technical field
The utility model belongs to simulation coal and gas prominent technology, particularly relates to a kind of energetic disturbance induction coal and gas prominent analogue experiment installation.
Background technology
Along with the increase of coal mining depth, enter deep high stress environment, architectonic effect significantly increases, impact the inducement of disaster change into concentrate dead load by near field gather the disturbance acting in conjunction of concentrating dynamic load with far field, coal and gas prominent disaster formation is more complicated, and existing research is static mostly or coal and gas prominent characteristic research under quasistatic effect, under causing complex geological condition, energetic disturbance induction coal and gas prominent disaster can not carry out effective prediction and prevention, very large threat is caused to mine safety High-efficient Production, particularly along with the increase of mining depth, this kind of disaster problem will become more outstanding.For this reason, the research to energetic disturbance induction coal and gas prominent mechanism under complex geological condition must be strengthened, particularly exploit energetic disturbance, self-weight stress field, tectonic stress field seem particularly important to the research of the coal and gas prominent mechanism under the multiple physical field coupling of seepage field and the development of corresponding experimental facilities.At present, the research method of coal and gas prominent rule mainly contains engineering site experiment, numerical simulation, outstanding statistics of features analysis and laboratory resemble simulation test, due to the dynamic phenomenon that coal and gas prominent is a kind of complexity, its danger occurred and sudden making are difficult to carry out Real-Time Monitoring research, and therefore room similarity simulation experiment is the effective ways of research coal and gas prominent rule by experiment.As far back as nineteen fifty-one USSR (Union of Soviet Socialist Republics) B.B. suddenly many top grades people just carried out coal and gas prominent simulation test first, started the new tool by simulation test research coal and gas prominent rule, after this state scholar such as Canadian, Japanese has successively carried out a series of coal and gas prominent resemble simulation test.The people such as Deng Quan envelope have carried out the coal and gas prominent simulation test research of China first in 1989, through the research and development of nearly 60 years, coal and gas prominent analogue means obtains significant progress, tested by One-dimensional simulation and develop into three-dimensional simulation experiment gradually, bring out outstanding means to open aspis till now fast by early stage Bian detonator blasting and utilize means such as impacting pouring weight applying impact load, monitoring instrument, means and monitoring parameter become abundant gradually, simulation coal sample size, charge pressure progressively become large, and sealing is also guaranteed gradually.But, existing analog simulation device become some there is not following problems:
One, general analog simulation device only considers the characteristic research of the coal and gas prominent under static state or quasistatic effect, in fact, have for 8669 times in the outstanding example of clear and definite operating type record in China, have blow out for 8362 times, supporting, coal breakage and the energetic disturbance operating type such as to drill induce outstanding, account for 96.5%, under understanding energetic disturbance effect, coal and gas prominent pests occurrence rule has important effect to the prevention of coal and gas prominent accident and improvement.
Two, after mineral resources enter deep mining, by " three high disturbances " effect, the inducement of coal and gas prominent dynamic disaster change into concentrate dead load by near field gather the disturbance acting in conjunction of concentrating dynamic load with far field, architectonic effect is simultaneously also in remarkable increase.But the current resemble simulation test energetic disturbance do not carried out under complex geological condition brings out the resemble simulation test research of coal and gas prominent.
Summary of the invention
The technical problems to be solved in the utility model: provide a kind of energetic disturbance to induce coal and gas prominent analogue experiment installation, does not consider to concentrate the disturbance of dynamic load and complex geological condition to cause in far field experimental result is inaccurate effectively to prevent and to administer the problems such as gas to solve prior art induction coal and gas prominent analogue experiment installation.
Technical solutions of the utility model:
A kind of energetic disturbance induction coal and gas prominent analogue experiment installation, it comprises experimental box body, the side plate all around of experimental box body, experimental box body top cover and experimental box body base plate form a seal chamber, separated by air permeable steel plate in the middle of seal chamber, cavity between experimental box body base plate to air permeable steel plate is analogy model chamber, between experimental box body top cover and air permeable steel plate, lifting jack is installed, the left side plate of seal chamber is fixed with stress wave conductive bar, experimental box body is provided with power charger, seal chamber is provided with data detection device.
At least four rhizoid bars are had to support between experimental box body base plate and experimental box body top cover, screw mandrel and being fixed by nut between experimental box body base plate and experimental box body top cover, power charger is pendulum, the fork of pendulum is connected on the side of experimental box body top cover left and right, when pendulum is vertical with experimental box body top cover, on the same line, the top of pendulum is provided with transmitter, is provided with velometer between the top of pendulum and stress wave conductive bar for the hammer portion of pendulum and the axle center of stress wave conductive bar.
Analogy model chamber is roof from top to bottom, coal seam and seat earth, and inside, coal seam has tunnel.
Analogy model chamber left side plate is pasted with air-permeable mattress, and stress wave conductive bar enters in coal seam through the air-permeable mattress on test box side, and the 30%-70% of stress wave conductive bar length enters coal seam.
First displacement meter group and the first taseometer group are installed in roof; Second displacement meter group and the second taseometer group are installed in seat earth; Often organize taseometer and often organize the quantity at least 6 of displacement meter.
Be equipped with transparent resin plate between coal seam and roof, transparent resin intralamellar part is provided with the second high-speed camera head, and tunnel internal frame is provided with supporting, and the first high-speed camera head is arranged in supporting, supporting is also provided with gas density probe.
At least two group sonic probes and one group of microseism probe is provided with at roof and seat earth interior zone.
Rear, the left and right side plate of experimental box body has the first air admission hole, the second air admission hole and the 3rd air admission hole, rear, left and right and front side board is respectively equipped with the first barometer group, the second barometer group, the 3rd barometer group and four barometer groups.
The beneficial effects of the utility model:
Adopt technical solutions of the utility model, compared with prior art, the utility model adopts pendulum impact stress wave conductive bar front end to produce dynamic loading, this dynamic loading is delivered on the assigned address of scale model coal seam and forms energetic disturbance, under the combined action of energetic disturbance, pressure from surrounding rock and gas pressure, coal sample is broken and is given prominence to from leakage test cabinet front plate opening; By the speed of velometer monitoring pendulum impact stress wave conductive bar, and by detecting element, the acoustic emission signal of the tunnel gas density of outstanding front and back, terrestrial stress, roof and floor displacement, coal and rock and microseismic signals etc. are detected in real time, just the pests occurrence rule research of coal and gas prominent can be induced to provide reliable basis for the energetic disturbance under complex geological condition by the data message gathered; Method of the present utility model is simple, and the apparatus structure adopted is simple, and result of use is good; Solve prior art induction coal and gas prominent analogue experiment installation not consider to concentrate the disturbance of dynamic load and complex geological condition to cause in far field experimental result is inaccurate effectively to prevent and to administer the problems such as gas.
Accompanying drawing explanation
Fig. 1 is the utility model structural representation;
Fig. 2 is the II---II cross-sectional schematic of Fig. 1.
Embodiment
A kind of energetic disturbance induction coal and gas prominent analogue experiment installation, it comprises experimental box body, the side plate all around 5 of experimental box body, experimental box body top cover 2 and experimental box body base plate 15 form a seal chamber, separated by air permeable steel plate 30 in the middle of seal chamber, cavity between experimental box body base plate 15 to air permeable steel plate 30 is analogy model chamber, lifting jack 3 is installed between experimental box body top cover 2 and air permeable steel plate 30, the left side plate of seal chamber is fixed with stress wave conductive bar 13, experimental box body is provided with power charger 7, seal chamber is provided with data detection device.
Lifting jack 3 provides vertically stress.
The effect of air permeable steel plate 30 is that the power of the lifting jack that the coal seam in casing is subject to can be uniformly distributed; Because air permeable steel plate 30 has gas penetration potential, make the good desorb of the gases such as gas and permeate in the object in experimental box body.
At least four rhizoid bars 4 are had to support between experimental box body base plate 15 and experimental box body top cover 2, screw mandrel and being fixed by nut 1 between experimental box body base plate 15 and experimental box body top cover 2, power charger 7 is pendulum, the fork of pendulum is connected on experimental box body top cover about 2 side, when pendulum is vertical with experimental box body top cover 2, the hammer portion of pendulum and the axle center of stress wave conductive bar 13 are on the same line, pendulum is provided with transmitter, velometer is provided with between the top of pendulum and stress wave conductive bar 13, the speed of pendulum is sent by control transmitter, the weight size of control pendulum and pendulum amplitude control the size of dynamic loading, by stress wave conductive bar 13 conducting power disturbance induction coal and gas prominent.
Analogy model chamber is roof 11 from top to bottom, coal seam 24 and seat earth 14, and inside, coal seam 24 has tunnel 9.
Analogy model chamber left side plate is pasted with air-permeable mattress 6, stress wave conductive bar (13) enters in coal seam 24 through the air-permeable mattress 6 on test box side, the 30%-70% of stress wave conductive bar 13 length enters coal seam 24, adopt air-permeable mattress 6, make the gases such as gas better make desorption of mash gas and absorption and coal seam; The 30%-70% of stress wave conductive bar 13 length enters coal seam 24, and the stress wave that pendulum can be made to beat generation is delivered in coal seam 25 uniformly,
First displacement meter group 8 and the first taseometer group 32 is installed in roof 11; Second displacement meter group 32 and the second taseometer group 12 is installed in seat earth 14; Often organize taseometer and often organize the quantity at least 6 of displacement meter; The object of taseometer group is that displacement meter is the deformation in order to detect roof 11 and seat earth 24 in order to detect stress in coal bed distribution.
Transparent resin plate 10 is equipped with between coal seam 24 and roof 11, transparent resin plate 10 inside is provided with the second high-speed camera head 25, tunnel 9 internal frame is provided with supporting, first high-speed camera head 22 is arranged in supporting, supporting is also provided with gas density probe 21, the object arranging transparent resin plate 10 facilitates the second high-speed camera head 25 for taking the change of coal body in the compression process of coal seam and outstanding process; First high-speed camera head 22 is arranged in supporting and observes rib and deformation of the surrounding rock in tunnel with realization by the first high-speed camera head 22, supporting is also provided with gas density probe 21, to detect tunnel gas density in real time.
Adopt transparent resin plate 10, the second high-speed camera head 25 is conveniently installed and conveniently takes coal seam disturbance near it and destroy situation.
At least two group sonic probes 18,29 and one group of microseism probe 23 is provided with at roof 11 and seat earth 14 interior zone.To realize the detection carrying out acoustic emission in energetic disturbance induction coal and gas prominent process, microseismic signals, judge fractured rock type according to signal type, and locate with acoustic emission, microseismic signals and determine to induce the feature of coal and gas prominent signal by energetic disturbance.
Rear, the left and right side plate of experimental box body has the first air admission hole 17, second air admission hole 19 and the 3rd air admission hole 20, the object of air admission hole facilitates air feed, rear, left and right and front side board is respectively equipped with the first barometer group 16, second barometer group 26, the 3rd barometer group 27 and four barometer groups 28, the gaseous tension in analogue experiment installation evenly can be detected, observation coal body gas pressure distribution, all air admission holes need sealing blocking in process of the test.
A kind of its test method of energetic disturbance induction coal and gas prominent analogue experiment installation, it comprises the steps:
Texture of coal seam in step 1, assembling experimental box body and analogy model chamber, according to analogy model chamber roof 11 from top to bottom, coal seam 24 and seat earth 14, and each detection means is installed;
Step 2, utilize the hydraulic jack 3 pairs of analogy model chambeies to apply original pressures, make the primary stress in analogy model chamber reach more than 0.1MPa.
Step 3, experimental box body to be vacuumized, until test casing air pressure inside is less than 50pa, then inject gas by air admission hole; The air admission hole sealing blocking of not using.
Step 4, the front end being sent pendulum impact stress wave conductive bar (13) by transmitter produce dynamic loading, this dynamic loading is delivered in analogy model the chamber in and forms energetic disturbance, and then induce coal and gas prominent;
Step 5, image data: before and after occurring coal and gas prominent, the acoustic emission signal of tunnel gas density, terrestrial stress, roof, seat earth displacement, coal and rock and microseismic signals detect in real time.
Inject gas by air admission hole described in step 3, gas method for implanting be: inject step by step from low pressure to high pressure, differing pressure 0.25Mpa between at different levels, wants interval 10-20 minute between at different levels; Object is in the coal body of initial stress area, form more and more higher free gas pressure and adsorption gas amount gradually, guarantees that the gas pressure numerical value of scale model to be measured reaches requirement of experiment.
Citing carries out refinement explanation to test method further below:
1, with reference to certain coal mine drilling data, obtain coal (rock) the layer attribute needed for the test of analogy model chamber, and the analog intensity value of coal (rock) layer is obtained according to the requirement of simulated experiment, utilize the preparation such as sand, calcium carbonate, gypsum, borax coal (rock) layer analog material, complete the installation of shaping, the Data Detection element of analog simulation model in test casing;
2, analog simulation model and coherent detection element are loaded in the analogy model chamber of test casing, hydraulic jack is utilized to add primary stress, when primary stress is greater than more than 0.1Mpa, in the past excavation tunnel, side plate openings place, and apply suitable supporting, in digging process, form periphery supporting pressure distribution, and form effective thickness coal body; With vacuum pump by experimental box body vacuum pumping; Make air pressure be less than 50pa, then inject gas by air admission hole, inject gas (for safety, available CO by peripheral inlet port
2), gas injects and will inject step by step from low pressure to high pressure, at different levelsly wants separated in time, forms more and more higher free gas pressure and adsorption gas amount gradually, guarantee that the gas pressure numerical value of scale model to be measured reaches requirement of experiment in the coal body of initial stress area;
3, after the primary stress in analogy model chamber and gas pressure reach required numerical value, send pendulum impact stress wave conductive bar 13 by transmitter and produce dynamic loading, the coal seam assigned address making this dynamic loading be delivered to scale model in analogy model chamber forms energetic disturbance, coal sample reduction under the combined action of energetic disturbance, pressure from surrounding rock and gas pressure is also given prominence to, by high-speed camera head record coal and gas prominent process from the opening of leakage test cabinet front plate; Measure pendulum from the speed before impact stress wave conductive bar 13 by velometer, and by detecting element, the acoustic emission signal of the tunnel gas density of outstanding front and back, terrestrial stress, roof and floor displacement, coal and rock and microseismic signals etc. are detected in real time.
4, gas (or CO is stopped
2) supply, shed the stress that hydraulic jack applies, open test casing, take out scale model model, the destruction situation of record analysis analog simulation model.
Gas pressure is gas (or the CO of 99.9% by concentration
2) tank provides, gas permeation speed has digitizing gas flow apparatus measures.
experimental principle:first application of vacuum is carried out to experimental box body before experiment, pump the air in scale model space, be then placed on experiment porch.Keep primary stress constant by hydraulic jack, by gas (or CO
2) gas pressure that maintains in experimentation of equalizing valve on tank is constant.After the numerical value that primary stress and gas pressure reach required, begin through transmitter again to send pendulum and hit stress wave conductive bar 13 and produce dynamic loading, this dynamic loading is delivered on scale model assigned address and forms energetic disturbance, coal sample reduction under the combined action of energetic disturbance, pressure from surrounding rock and gas pressure is also given prominence to from the downside of leakage test casing.Finally by the data in the instruments such as velometer, primary stress controller, gas pressure controller, displacement meter, taseometer, sonic probe and microseism probe, draw the pests occurrence rule of the energetic disturbance induction coal and gas prominent under complex geological condition.
Claims (8)
1. an energetic disturbance induction coal and gas prominent analogue experiment installation, it comprises experimental box body, the side plate all around (5) of experimental box body, experimental box body top cover (2) and experimental box body base plate (15) composition seal chamber, it is characterized in that: separated by air permeable steel plate (30) in the middle of seal chamber, cavity between experimental box body base plate (15) to air permeable steel plate (30) is analogy model chamber, lifting jack (3) is installed between experimental box body top cover (2) and air permeable steel plate (30), the left side plate of seal chamber is fixed with stress wave conductive bar (13), experimental box body is provided with power charger (7), seal chamber is provided with data detection device.
2. a kind of energetic disturbance induction coal and gas prominent analogue experiment installation according to claim 1, it is characterized in that: between experimental box body base plate (15) and experimental box body top cover (2), have at least four rhizoid bars (4) to support, screw mandrel and between experimental box body base plate (15) and experimental box body top cover (2) by nut (1) fix, power charger (7) is pendulum, the fork of pendulum is connected on the side of experimental box body top cover (2) left and right, when pendulum is vertical with experimental box body top cover (2), the hammer portion of pendulum and the axle center of stress wave conductive bar (13) are on the same line, the top of pendulum is provided with transmitter, velometer is provided with between the top of pendulum and stress wave conductive bar (13).
3. a kind of energetic disturbance induction coal and gas prominent analogue experiment installation according to claim 1, it is characterized in that: analogy model chamber is roof (11) from top to bottom, coal seam (24) and seat earth (14), coal seam (24) inside has tunnel (9).
4. a kind of energetic disturbance induction coal and gas prominent analogue experiment installation according to claim 1, it is characterized in that: analogy model chamber left side plate is pasted with air-permeable mattress (6), stress wave conductive bar (13) enters in coal seam (24) through the air-permeable mattress (6) on test box side, and the 30%-70% of stress wave conductive bar (13) length enters coal seam (24).
5. a kind of energetic disturbance induction coal and gas prominent analogue experiment installation according to claim 3, is characterized in that: be provided with the first displacement meter group (8) and the first taseometer group (32) in roof (11); Second displacement meter group (32) and the second taseometer group (12) are installed in seat earth (14); Often organize taseometer and often organize the quantity at least 6 of displacement meter.
6. a kind of energetic disturbance induction coal and gas prominent analogue experiment installation according to claim 3, it is characterized in that: between coal seam (24) and roof (11), be equipped with transparent resin plate (10), transparent resin plate (10) inside is provided with the second high-speed camera head (25), tunnel (9) internal frame is provided with supporting, first high-speed camera head (22) is arranged in supporting, supporting is also provided with gas density probe (21).
7. a kind of energetic disturbance induction coal and gas prominent analogue experiment installation according to claim 3, is characterized in that: be provided with at least two group sonic probes (18,29) and one group of microseism probe (23) at roof (11) and seat earth (14) interior zone.
8. a kind of energetic disturbance induction coal and gas prominent analogue experiment installation according to claim 1, it is characterized in that: rear, the left and right side plate of experimental box body has the first air admission hole (17), the second air admission hole (19) and the 3rd air admission hole (20), rear, left and right and front side board is respectively equipped with the first barometer group (16), the second barometer group (26), the 3rd barometer group (27) and four barometer groups (28).
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| CN201420456712.XU CN204214713U (en) | 2014-08-14 | 2014-08-14 | A kind of energetic disturbance induction coal and gas prominent analogue experiment installation |
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| CN201420456712.XU CN204214713U (en) | 2014-08-14 | 2014-08-14 | A kind of energetic disturbance induction coal and gas prominent analogue experiment installation |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104132844A (en) * | 2014-08-14 | 2014-11-05 | 贵州大学 | Dynamic disturbance induction coal and gas outburst simulation experiment device and experiment method |
| CN112053618A (en) * | 2020-08-17 | 2020-12-08 | 中煤科工集团重庆研究院有限公司 | Coal and gas outburst disaster simulation box |
-
2014
- 2014-08-14 CN CN201420456712.XU patent/CN204214713U/en not_active Withdrawn - After Issue
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104132844A (en) * | 2014-08-14 | 2014-11-05 | 贵州大学 | Dynamic disturbance induction coal and gas outburst simulation experiment device and experiment method |
| CN112053618A (en) * | 2020-08-17 | 2020-12-08 | 中煤科工集团重庆研究院有限公司 | Coal and gas outburst disaster simulation box |
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Granted publication date: 20150318 Effective date of abandoning: 20170412 |