CN101354356B - Coal rock solid gas coupling fine observation mechanics loading device - Google Patents
Coal rock solid gas coupling fine observation mechanics loading device Download PDFInfo
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- CN101354356B CN101354356B CN200810070167XA CN200810070167A CN101354356B CN 101354356 B CN101354356 B CN 101354356B CN 200810070167X A CN200810070167X A CN 200810070167XA CN 200810070167 A CN200810070167 A CN 200810070167A CN 101354356 B CN101354356 B CN 101354356B
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Abstract
The invention discloses a solid and gas coupling mesomechanics charger of coal rocks, which has the following structure: a testing body is opened with a testing cavity, a measuring orifice and a multi-purpose air vent, a transparent sight glass is fixed at an opening position of the testing cavity, a measuring conducting wire is arranged inside the measuring orifice, an inner port of the multi-purpose air vent is positioned on an inner wall of the testing cavity, and an outer port of the multi-purpose air vent is connected with a gas pipe; a cushion block, a limit pressure head and a loading head are arranged inside the testing cavity, an upper part of the cushion block is opened with an L-shaped nick, a vertical surface of the L-shaped nick is over against the limit pressure head that is fixed at an inner end of a limit rod, and a transverse surface of the L-shaped nick is over against the loading head that is fixed at a lower end of a loading rod. The solid and gas coupling mesomechanics charger can implement not only the uniaxial mechanics test under the solid and gas coupled environment but also the plane strain mechanics test under the solid and gas coupled environment, provides reliable testing conditions for the solid and gas coupling mesomechanics test that collects image signals and acoustic emission signals that are inspected microscopically in real time, and leads the research environment of the coal and gas prominent mechanism test to be closer to real mine environment.
Description
Technical field
The present invention relates to a kind of fine observation mechanical test device of coal containing methane gas rock, relate in particular to coal rock solid gas coupling fine observation mechanics loading device, be applicable to the fine observation mechanical test of coal petrography unstable failure whole deformation process under the different gas pressure effects.
Background technology
Along with continuing to increase of the coal in China depth of excavation and intensity, the mine coal rock dynamic disaster is more serious, and China's national product has been brought great negative effect, and is wherein outstanding serious with coal and gas especially.Research coal and gas acting in conjunction mechanism, coal and the gas dynamic action process in resource exploitation, to the development of China and world's coal industry, the outstanding disaster of control mine coal and gas has the important techniques supporting role.Current, in the research of coal and gas outburst mechanism, the coal body physico mechanical characteristic is to disclose the important channel that coal and gas are given prominence to coal and gas interaction mechanism in the process under the complex conditions, and existing macroscopical experimental study also has many inexplicable phenomenons.Angle from mesomechanics research, deformation failure feature in conjunction with the coal body macroscopic view, grasp the coal containing methane gas body and carefully see the rule of deformation failure, can be for the outstanding relevant issues of coal and gas give the more explanation of science, further announcement coal and gas outburst mechanism and the more scientific and reasonable Prevention Technique of proposition are had important theory and engineering using value.
At present, many scholars have begun the distortion and the destructive process of coal petrography under the effect of thin sight angle research gas.Liu Baochen etc. utilize rigidity loading system and scanning electron microscope that mining area, Datong District hard coal has been carried out mechanical test and static microscopic observation, because scanning electron microscope is had relatively high expectations to experimental enviroment vacuum tightness, such test does not relate to coal and the outstanding relevant solid and gas coupling of gas environment; Ge Xiurun etc. utilize design voluntarily and development with the supporting special-purpose loading equipemtn of CT machine, carried out the instant Dynamic CT test of the microscopic damage evolution rule of coal petrography destructive process under three and the uniaxial load effect, but this equipment still can't realize the test under the gas pressure; Feng Xiating etc. have invented and can carry out rock burst fine observation mechanical test under stress-current-three couplings of chemical corrosion and the different confined pressures, and the crack propagation process of sample is carried out micro-amplification and CCD observation, and (application number: 200410061234.3), its deficiency is that the coal sample that can not carry out the gas pressure effect is under tested; Professors He Xueqiu etc. once studied the microscopic observation of coal containing methane gas distortion and destructive process, and realized that microscopic observation combines with dynamic test, but its coal sample test specimen stress is single, observation scope only is the very little part of test specimen one lateral area, lack the acoustic emission parameter estimator that test specimen destroys, but the comprehensive comparative of test result is poor.
Summary of the invention
Technical matters to be solved by this invention is to provide a kind of coal rock solid gas coupling fine observation mechanics loading device, can carry out solid and gas coupling test under single shaft and the plane strain loading environment, and realizes the collection of real-time microscopic observation and acoustic emission signal.
Technical scheme of the present invention is as follows: a kind of coal rock solid gas coupling fine observation mechanics loading device, on the test body, offer test chamber, measured hole and use pore more, wherein the open-mouth of test chamber is fixed with transparent visor by gland, in described measured hole, wear the measurement lead, the inner of this measurement lead is arranged in test chamber, measuring the outer end of lead draws from the side of test body, described many inwalls that is positioned at test chamber with the inner port of pore, the external port of using pore in the side of test body more, and the external port place is connected with tracheae; In described test chamber, be provided with cushion block, spacing pressure head and loading head, wherein the top of cushion block offers " L " v notch v, the longitudinal surface that is somebody's turn to do " L " v notch v is over against spacing pressure head, spacing pressure head is fixed in the inner of gag lever post, it is external that test is stretched out in the outer end of gag lever post, and spacing by latch mechanism, and the athwartship plane of described " L " v notch v is over against loading head, this loading head is fixed in the lower end of load bar, and it is external that the upper end of described load bar protrudes upward test.
Among the present invention, test chamber is the place that test is carried out, and is used to place test block; Cushion block and spacing pressure head are arranged in the test chamber, can limit the test block lateral shift, the plane strain stress state is provided.Transparent visor mainly provides the solid and gas coupling environment in the test chamber and creates the microscopic observation condition that test specimen destroys.Measure the external surveying instrument of lead and test and is connected, with measuring-signals such as transmission acoustic emission, strain, stress, realization is to comprehensive measurement of test specimen destructive process.Many tracheaes of drawing with pore are divided into two-way, and one the tunnel is connected with vaccum-pumping equipment, and another road is connected with extraneous high-pressure air feed equipment, so that on request test chamber is vacuumized before pressure test and fill gas and operate.
When the present invention is used to test, earlier gland and transparent visor are pulled down, the inner probe of measuring lead is abutted in coal petrography test block surface, then the coal petrography test block is positioned on the athwartship plane of cushion block " L " v notch v, regulate latch mechanism, gag lever post is inwardly stretched, and spacing pressure head leans the side at test block, and applies certain pressure, test block is clamped between the longitudinal surface of spacing pressure head and cushion block " L " v notch v, with transparent visor reduction, seal again, fastening.Then this device integral body is placed on the implosion test machine, opens vaccum-pumping equipment, by tracheae and many with pore to vacuumizing in the test chamber, reach the certain vacuum degree after, close vaccum-pumping equipment; Open high-pressure air feed equipment, by tracheae and many with pore to filling gas in the test chamber, reach certain pressure after, make pressure stability and keep certain hour, test chamber build-in test spare is fully adsorbed gas.Open testing machine and surveying instrument, testing machine transfers the pressure on the test block by load bar and loading head, carry out the solid and gas coupling mechanical test under the gas pressure effect, real-time microscopic observation just can be carried out in the transparent visor of the test body outside, surveying instrument is gathered measuring-signals such as acoustic emission, strain, stress by measuring lead, realizes the comprehensive measurement to the test block destructive process.
Different gas pressures and different loads all can have different influences to the failure mode of coal petrography test specimen, process, speed etc.Apparatus of the present invention are exactly to provide effective means for fine observation mechanical test that needs carry out horizontal image signal and acoustic emission signal collection, for the theoretical analysis of solid and gas coupling coal petrography unstable failure under the different situations provides experimental basis.
Above-mentioned latch mechanism is locked column, locking beam and set nut by rigidity and is constituted, two rigidity locking column vertical fixing are in the side of test body, and separation is in the upper and lower both sides of gag lever post, kink locking beam on two rigidity locking column, the pre-load nut that the middle part of this locking beam inside surface is overlapped admittedly to the gag lever post outer end is spacing, and the upper and lower part of locking beam outside surface is spacing by the set nut of suit on two rigidity locking columns respectively.Latch mechanism and gag lever post and spacing pressure head design for the simulation plane strain loaded condition, regulate two set nuts, make the direction motion of locking beam towards the test body, the locking beam inwardly pushes up gag lever post and spacing pressure head, thereby makes the test block side be subjected to certain position-limiting action power.Above mechanism is not only simple and practical, and good reliability.
For the ease of processing and assembling, above-mentioned test chamber be a circle, and is inner small and outside big step-like, and described cushion block, spacing pressure head and loading head are positioned at the reduced diameter section of test chamber, and transparent visor and gland are positioned at the enlarged diameter section of test chamber.
Locate in the test chamber conveniently, stablize for cushion block is placed into, above-mentioned cushion block adopts cambered surface to contact with the chamber wall of test chamber.The radius of this cambered surface equates with the radius of described test chamber reduced diameter section.
Be easy disassembly, and make that transparent visor is fixed, above-mentioned transparent visor is a disc, and gland is an annular, and gland is arranged on the outward flange of transparent visor, and fixes by equally distributed screw on the circumference and test body.
Seal by the O RunddichtringO between above-mentioned transparent visor and the test body; Adopt O RunddichtringO and two combination seal sealings that the Yx RunddichtringO constitutes between load bar and the test body, the outside of combination seal is spacing by tegillum, and tegillum is being tested on the body by screw retention; Described gag lever post is identical with sealing means and the load bar tested between the body.More than design can guarantee that test chamber all has good air-tightness vacuumizing (negative pressure) and fill under methane gas (malleation) situation.
The invention has the beneficial effects as follows:
1, can provide reliable experimental basis for the solid gas coupling fine observation mechanics test of carrying out real-time microscopic observation and acoustic emission signal collection.
2, various piece fixture and the spacing facility of side direction guaranteed that the present invention both can carry out the single shaft mechanical test, also can carry out the plane strain mechanical test.
3, this device has good air-tightness and anti-quick-fried property, can carry out the fine observation mechanical test under the different gas pressure effects, has created the test condition more approaching with mine reality in particular for coal petrography fine observation mechanical test under the gas pressure effect.
4, this apparatus structure is simple, and processing cost is low, and good reliability can be tested the test block of multiple shapes such as rectangular parallelepiped, right cylinder, different size, and is widely applicable.
Description of drawings
Fig. 1 is a structural representation of the present invention.
Fig. 2 is the A-A cut-open view of Fig. 1.
Embodiment
The invention will be further described below in conjunction with drawings and Examples:
As shown in Figure 1 and Figure 2, test body 1 be a cube structure, offers test chamber 2 in test on the body 1, and the opening of this test chamber 2 is positioned at the front of test body 1, and test chamber 2 is a circle, and is inner small and outside big step-like.The open-mouth that transparent visor 6 and gland 5 are positioned at test chamber 2 is an enlarged diameter section, wherein transparent visor 6 is a disc, the inside surface of transparent visor 6 is spacing by the step surface in the test chamber 2, seal by the O RunddichtringO between transparent visor 6 and the test body 1, gland 5 is an annular, gland 5 is arranged on the outward flange of transparent visor 6, and fixing with test body 1 by equally distributed screw on the circumference.The microscopic observation that described transparent visor is an entire test has been created test condition.
From Fig. 1, Fig. 2 as can be known, offer measured hole 3 and many with pore 4 on the right side of test chamber 2, measured hole 3 is positioned at many tops with pore 4, and the inner port of measured hole 3 is positioned at the inwall of test chamber 2, and the external port of measured hole 3 is at the right flank of test body 1.In described measured hole 3, wear and measure lead 7, the inner of this measurement lead 7 is arranged in test chamber 2, measure the outer end of lead 7 and pass the seal that is provided with in the measured hole 3, and from the test body 1 right flank draw, be connected with corresponding surveying instrument (not drawing among the figure) then, surveying instrument is gathered measuring-signals such as acoustic emission, strain, stress by measuring lead 7, to realize the comprehensive measurement to the test block destructive process.Described many inwalls that is positioned at test chamber 2 with the inner port of pore 4, the right flanks of using the external port of pore 4 at test body 1 more, and the external port place is connected with tracheae 8, the tracheae that this tracheae 8 is drawn is divided into two-way, one the tunnel is connected with vaccum-pumping equipment, another road is connected with extraneous high-pressure air feed equipment, so that on request test chamber is vacuumized before pressure test and fill gas operation.
From Fig. 1, Fig. 2 further as can be known, in the reduced diameter section of described test chamber 2, be provided with cushion block 9, spacing pressure head 10 and loading head 11, wherein cushion block 9 is cambered surface with the chamber wall of test chamber 2 and contacts, and the radius of this cambered surface equates with the radius of described test chamber 2 reduced diameter sections.Upper left quarter at cushion block 9 offers " L " v notch v, the athwartship plane that is somebody's turn to do " L " v notch v is over against loading head 11, this loading head 11 is fixed in the lower end of the load bar 12 of vertical layout, the upper end of load bar 12 protrudes upward outside the upper surface of test body 1, moving up and down of load bar 12 controlled by the implosion test machine, the implosion test machine is public technology, and its structure and principle are not done at this and given unnecessary details.The upper end in the hole that wears for load bar 12 on the described test body 1 is step-like, and be provided with O RunddichtringO 17 and two combination seals that Yx RunddichtringO 18 constitutes in the step section, there is tegillum 19 outside of combination seal, combination seal is to sealing between load bar 12 and the test body 1, tegillum 19 by screw retention the test body 1 on, spacing to combination seal.
From Fig. 1, Fig. 2 also as can be known, the longitudinal surface of cushion block 9 " L " v notch v is over against spacing pressure head 10, spacing pressure head 10 is fixed in the inner of horizontally disposed gag lever post 21, and stretch out outside the left surface of test body 1 outer end of gag lever post 21, and the end suit pre-load nut 16 of outer end.Two rigidity locking column 13 vertical fixing are in the left surface of test body 1, and separation is in the upper and lower both sides of gag lever post 21, kink locking beam 14 on two rigidity locking column 13, the middle part of these locking beam 14 inside surfaces is spacing to gag lever post 21, and the upper and lower part of locking beam 14 outside surfaces is spacing by the set nut 15 of suit on two rigidity locking columns 13 respectively.The outer end in the hole that wears for gag lever post 21 on the described test body 1 is step-like, and O RunddichtringO and two combination seals that the Yx RunddichtringO constitutes are installed in the step section, there is tegillum the outside of combination seal, combination seal is placed on the gag lever post 21, to sealing between gag lever post 21 and the test body 1, tegillum by screw retention the test body 1 on, spacing to combination seal.
The present invention is work like this:
1, earlier gland 5 and transparent visor 6 are pulled down, the inner probe of measuring lead 7 is abutted in coal petrography test block 20 surfaces, then test block 20 is positioned on the athwartship plane of cushion block 9 " L " v notch v, regulate two set nuts 15, make of the direction motion of locking beam 14 towards test body 1, locking beam 14 inwardly pushes up gag lever post 21 and spacing pressure head 10, thereby make test block 20 sides be subjected to certain position-limiting action power, test block 20 is clamped between the longitudinal surface of spacing pressure head 10 and cushion block 9 " L " v notch v, again with transparent visor 6 and gland 5 reduction, sealing, fastening.
2, this device integral body is placed on the implosion test machine, load bar 12 is over against the loading head of testing machine.
3, open vaccum-pumping equipment, by tracheae 8 and manyly vacuumize with 4 pairs of test chambers 2 of pore, reach the certain vacuum degree after, close vaccum-pumping equipment.
4, open high-pressure air feed equipment, by tracheae 8 and many with filling gas in 4 pairs of test chambers of pore, reach certain pressure after, make pressure stability and keep certain hour.
5, open testing machine and surveying instrument, testing machine transfers the pressure on the test block 20 by load bar 12 and loading head 11, carry out the solid and gas coupling mechanical test under the gas pressure effect, real-time microscopic observation just can be carried out in the transparent visor of test body 6 outsides, utilize surveying instrument to gather measuring-signals such as acoustic emission, strain, stress by measuring lead 7, to realize comprehensive measurement to the test block destructive process.
Claims (6)
1. coal rock solid gas coupling fine observation mechanics loading device, it is characterized in that: on test body (1), offer test chamber (2), measured hole (3) and many with pore (4), wherein the open-mouth of test chamber (2) is fixed with transparent visor (6) by gland (5), in described measured hole (3), wear and measure lead (7), the inner of this measurement lead (7) is arranged in test chamber (2), measuring the outer end of lead (7) draws from the side of test body (1), described many inwalls that is positioned at test chamber (2) with the inner port of pore (4), the external port of using pore (4) in the side of test body (1) more, and the external port place is connected with tracheae (8); In described test chamber (2), be provided with cushion block (9), spacing pressure head (10) and loading head (11), wherein the top of cushion block (9) offers " L " v notch v, the longitudinal surface that is somebody's turn to do " L " v notch v is over against spacing pressure head (10), spacing pressure head (10) is fixed in the inner of gag lever post (21), stretch out outside the test body (1) outer end of gag lever post (21), and it is spacing by latch mechanism, the athwartship plane of described " L " v notch v is over against loading head (11), this loading head (11) is fixed in the lower end of load bar (12), and the upper end of described load bar (12) protrudes upward outside the test body (1).
2. coal rock solid gas coupling fine observation mechanics loading device according to claim 1, it is characterized in that: described latch mechanism is locked column (13) by rigidity, locking beam (14) and set nut (15) constitute, two rigidity locking column (13) vertical fixing are in the side of test body (1), and separation is on horizontally disposed gag lever post (21), following both sides, go up kink locking beam (14) at two rigidity locking columns (13), the pre-load nut (16) that the middle part of this locking beam (14) inside surface is overlapped admittedly to gag lever post (21) outer end is spacing, on locking beam (14) outside surface, the bottom is spacing by the set nut (15) of the last suit of two rigidity locking columns (13) respectively.
3. coal rock solid gas coupling fine observation mechanics loading device according to claim 1 and 2, it is characterized in that: described test chamber (2) is for circular, and be inner small and outside big step-like, described cushion block (9), spacing pressure head (10) and loading head (11) are positioned at the reduced diameter section of test chamber (2), and transparent visor (6) and gland (5) are positioned at the enlarged diameter section of test chamber (2).
4. coal rock solid gas coupling fine observation mechanics loading device according to claim 3 is characterized in that: described cushion block (9) adopts cambered surface to contact with test chamber (2) chamber wall, and the radius of this cambered surface equates with the radius of described test chamber (2) reduced diameter section.
5. coal rock solid gas coupling fine observation mechanics loading device according to claim 3, it is characterized in that: described transparent visor (6) is disc, gland (5) is an annular, gland (5) covers on the outward flange of transparent visor (6), and fixing by equally distributed screw on the circumference and test body (1).
6. coal rock solid gas coupling fine observation mechanics loading device according to claim 5 is characterized in that: seal by the O RunddichtringO between described transparent visor (6) and the test body (1); The combination seal sealing of adopting O RunddichtringO (17) and two Yx RunddichtringOs (18) to constitute between described load bar (12) and the test body (1), the outside of combination seal is spacing by tegillum (19), and tegillum (19) is being tested on the body (1) by screw retention; Sealing means between described gag lever post (21) and the test body (1) is identical with load bar (12).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200810070167XA CN101354356B (en) | 2008-08-22 | 2008-08-22 | Coal rock solid gas coupling fine observation mechanics loading device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200810070167XA CN101354356B (en) | 2008-08-22 | 2008-08-22 | Coal rock solid gas coupling fine observation mechanics loading device |
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| CN101354356A CN101354356A (en) | 2009-01-28 |
| CN101354356B true CN101354356B (en) | 2010-10-27 |
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| CN200810070167XA Expired - Fee Related CN101354356B (en) | 2008-08-22 | 2008-08-22 | Coal rock solid gas coupling fine observation mechanics loading device |
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Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102621228B (en) * | 2012-03-20 | 2014-02-12 | 中国矿业大学(北京) | Acoustic and electric parameter measuring device used for loading procedure of gas-containing coal bodies |
| CN103398903A (en) * | 2013-08-07 | 2013-11-20 | 重庆大学 | Gas-containing coal rock testing method |
| CN104089822B (en) * | 2014-05-16 | 2017-01-18 | 山东科技大学 | Deep mining stress field evolution process test method |
| CN109142028B (en) * | 2018-08-20 | 2020-11-03 | 山东科技大学 | Coal seam deformation test device caused by working face tunneling |
| CN109916750A (en) * | 2019-04-09 | 2019-06-21 | 重庆大学 | Coal and gas prominent simulation test test piece box |
| CN111964733A (en) * | 2020-09-16 | 2020-11-20 | 中国矿业大学(北京) | Digital-image real-time monitoring experimental device under condition of symmetrically decompressing gas and breaking coal |
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