CN104897322B - A kind of bearing plate of the end face of collection coal and rock in real time each point vertical stress - Google Patents
A kind of bearing plate of the end face of collection coal and rock in real time each point vertical stress Download PDFInfo
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- CN104897322B CN104897322B CN201510346615.4A CN201510346615A CN104897322B CN 104897322 B CN104897322 B CN 104897322B CN 201510346615 A CN201510346615 A CN 201510346615A CN 104897322 B CN104897322 B CN 104897322B
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- carrying ring
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- face
- rock
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- 238000012360 testing method Methods 0.000 abstract description 27
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- 238000000034 method Methods 0.000 abstract description 10
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- 238000012669 compression test Methods 0.000 description 3
- 238000006073 displacement reaction Methods 0.000 description 3
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- 230000008569 process Effects 0.000 description 3
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- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
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- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
Abstract
A kind of bearing plate of the end face of collection coal and rock in real time each point vertical stress,Mainly include bolster stake,Load-carrying ring,Vertical strain piece,Horizontal strain piece,Wire and base,It is characterized in that bolster stake is positioned at positive middle part,Multiple load-carrying rings are cased with outside bolster stake,The number of load-carrying ring can accordingly increase and decrease according to the size of measured rock sample,There is compensation space between adjacent load-carrying ring,The middle and lower part of bolster stake and load-carrying ring is provided with circumferential groove,Horizontal strain piece and vertical strain piece are distributed with circumferential groove,Foil gauge is distributed in pairs,And it is connected with wire,The bottom side of load-carrying ring offers hub slot,The bottom of load-carrying ring is provided with horizontal grooving,Hub slot and horizontal grooving are on same vertical plane,It can mutually coincide and export wire,The bottom of bolster stake and load-carrying ring is provided with base,Strong adaptability of the present invention,Technique effect is good,Eliminate test specimen effect of end surface in Failure under Uniaxial Compression,And test specimen end face vertical stress can be realized.
Description
Technical field
The present invention relates to the test device of coal and rock end face stress, the more particularly to a kind of end face of collection coal and rock in real time each point
The bearing plate of vertical stress.
Background technology
In Geotechnical Engineering and mining engineering field, the mechanical property that understands rock or coal body be carry out successive projects it is big before
One of carry, only after fully rock items mechanics parameter is grasped, it could fully assess the possibility of engineering construction and to it
Instructed.Total well known, rock is the heterogeneous material for possessing natural defect, and its every mechanical index needs will be live and real
Test room and assess test and combine and can just obtain defining for accurate science.Test under current technical status to its mechanical property is more
Carried out in labs, the unified standard reached according to ISRM, its common method of testing has single shaft pressure
Contracting method, triaxial compressions method and Brazilian split the law.Wherein uniaxial compression test is used for determining rock sample in uniaxial tension bar
Under part axially and radially（Laterally）Strain value, and the modulus of elasticity and Poisson's ratio of rock are further calculated, simple to operate, knot
Fruit is reliable, time-consuming shorter, therefore application of the uniaxial compression test in terms of material properties of rock measure is extremely wide and by international same
Row accreditation.
In recent years, acoustic emission test technology also plays important role, sound emission in terms of material properties of rock measure
The rule that technology can be detected preferably and internal crack extends, extended, crossing during the inverting rock failure mechanism of rock, its rule drawn
The rule drawn can be tested with uniaxial compression to cooperate to improve the accuracy of test result, these are applied in rock sample
It is particularly important in terms of internal injury mechanism and extensively.Acoustic emission test technology and uniaxial compression experiment be combined with each other and can obtained
Know crack closing stress threshold value, crack initiation stress threshold, damage dilatancy threshold value and the peak value in rock sample destructive process
Stress threshold, while the characteristics of source of damage positioning, is possessed based on sound emission, this technology can be broken inside precise positioning rock sample
Bad originated location and Extended workflow-net.
However, acoustic emission and uniaxial compression test are also by certain limitation.This limitation is mainly manifested in
Two aspects：First, stress concentration caused by uniaxial compression, this stress concentration has all embodied on the whole end face of rock sample,
But the center shaft attachment of rock sample is concentrated mainly on, so as to cause the uneven distribution situation of end stress, and forcing
During nearly peak stress, stress herein even can be higher than the original uniaxial compressive strength of sample, and this has greatly interfered with rock sample power
Learn the accuracy of parameter output.Main cause is that the transversely deforming of rock sample is largely put to the test machine pressure-bearing platform up and down
Influence, especially upper and lower end face.Axial compressive force and horizontal frictional resistance stress effect between end face and pressure-bearing platform cause test specimen originally
The transversely deforming that should be embodied is limited, and so as to trigger stress concentration, this stress concentration then embodies closer to test specimen axle portion
Ground is more obvious.Second aspect is the interference to sound emission, and in fact rational situation is：In the early stage of uniaxial compression experiment
Seldom acoustic emission test specimen is detected.But just because of End frictional effect, rock microparticle on end face with
It will occur to roll, rotate and crush between pressure-bearing platform, these small events will be considered as rock itself acoustic emission signal and quilt
Capture, so as in the accuracy of virtually severe jamming acoustic emission detection.Especially when acoustic emission positioning needs, early stage is visited
The acoustic emission source of survey may integrated distribution in upper and lower end face position, this will produce great to final overall acoustic emission source positioning
Error interference.
Therefore it is badly in need of that a kind of strong adaptability, technique effect are good, the rock or coal body of varying strength is adapted to, to sample chi
It is very little to require than broad, test specimen effect of end surface in Failure under Uniaxial Compression can be eliminated and test specimen end face vertical stress can be realized
Bearing plate
The content of the invention
In order to overcome stress concentration caused by uniaxial compression present in prior art, so as to cause the inequality of end stress
Even distribution scenario, and then the accuracy of rock sample mechanics parameter output is disturbed, and the deficiency of the interference to sound emission, this
Invention provides that a kind of strong adaptability, technique effect are good, the rock or coal body of varying strength is adapted to, to specimen size requirement
Than broad, test specimen effect of end surface in Failure under Uniaxial Compression is eliminated, and can realize that one kind of test specimen end face vertical stress is real
When gather the bearing plate of coal and rock end face each point vertical stress.
The technical scheme adopted by the invention to solve the technical problem is that：A kind of end face of collection coal and rock in real time each point is vertical
The bearing plate of stress, mainly including bolster stake, load-carrying ring, vertical strain piece, horizontal strain piece, wire and base, bolster stake position
In positive middle part, multiple highly equal load-carrying rings are cased with along the radial direction outside bolster stake, the upper and lower end face of load-carrying ring is all
In same level, and the central axis of bolster stake and load-carrying ring overlaps, and the number of load-carrying ring can be according to measured rock
The size of stone sample and accordingly increase and decrease, have compensation space between adjacent load-carrying ring, to adapt to sample end face in compression process
Transversely deforming, the middle and lower part of bolster stake and load-carrying ring is provided with circumferential groove, is distributed with the circumferential groove of bolster stake and load-carrying ring
Horizontal strain piece and vertical strain piece, horizontal strain piece and vertical strain piece are distributed in pairs, and can installing/dismounting, be easy to
Change, to ensure the validity of each foil gauge, foil gauge is respectively connected with wire, can spread out of data, the bottom of load-carrying ring
Side offers hub slot, and for concentrating the wire of output, the bottom of load-carrying ring is provided with horizontal grooving, hub slot and horizontal cutting
Groove can mutually coincide on same vertical plane and export wire, the bottom of bolster stake and load-carrying ring is provided with base；Described
The end face diameter of bolster stake is 0.5~3 cm, is highly 10~15 cm, and the quantity of described load-carrying ring is 6~10, carrying
The ring end surface thickness of ring is 0.7~1.5 cm, is highly 10~15 cm, and the width in described compensation space is 2~4 mm,
A diameter of 14~24 cm of described base, it is highly 1~2 cm；Opened up on described bolster stake and the outer wall of load-carrying ring
Ring groove depth is 2 mm, and to arrange full-bridge strain acquisition system, described vertical strain piece and horizontal strain piece are equidistant
Be distributed in circumferential groove, and foil gauge is respectively connected with wire, and data are spread out of, and the fluting of described circumferential groove is highly 2
~3 cm, the groove width and height of hub slot are respectively 5 mm and 1~1.5 cm, and the length and height of horizontal grooving are respectively
2~4 cm and 0.5~1 cm；Wire is connected in turn on static resistance strain acquisition system according to the label of each load-carrying ring.
Beneficial effects of the present invention：Compared with the closed bearing plate employed in the experiment of traditional uniaxial compression, this hair
A kind of bearing plate of end face of collection coal and rock in real time each point vertical stress of bright proposition has the advantages of many：First, the present invention
The bearing plate of proposition avoids effect of end surface, and the end face frictional resistance effect being subject in conventional rock sample pressurized process is eliminated, by
Space is compensated between each load-carrying ring to the compensating action of transverse strain, the transversely deforming of each position will be no longer by beam on sample
Tie up and become more free；Second, the vertical stress of each position in end face can obtain effectively in rock sample pressurized process
Collection, end face vertical stress cloud charts can be simultaneously drawn out based on this, and this is that impossible realize in the experiment of traditional uniaxial compression
, the drafting of this end face vertical stress is for the stress of the various coal columns or filled wall bodies of gob-side retained entries left in colliery scene
Research has particularly important guiding significance；3rd, due to eliminating the frictional resistance effect of end face, height is caused in rock test
Accurate synchronization collection acoustic emission signal be achieved, especially initial crack sprout, extension phase, although each load-carrying ring
In the arrangement of space independently of one another, it is but coordinated with each other in terms of rock sample transversely deforming is adapted to, it effectively prevent due to end
The interference acoustic emission signal that face rubs and triggered.
In general, the bearing plate adaptability of a kind of end face of collection coal and rock in real time each point vertical stress proposed by the present invention
By force, technique effect is good, adapts to the rock or coal body of varying strength, can be standard to specimen size requirement than broad
Cylindrical sample, or cuboid sample, eliminate test specimen effect of end surface in Failure under Uniaxial Compression, and test specimen can be realized
End face vertical stress, using the teaching of the invention it is possible to provide a kind of more accurately rock mechanics testing scheme, so as to make finger for field engineering practice
The property led is evaluated.
Brief description of the drawings
Fig. 1 is vertical section schematic diagram of the present invention；
1. bolster stake in figure, 2. load-carrying rings, 3. compensation spaces, 4. vertical strain pieces, 5. circumferential grooves, 6. horizontal strain pieces,
7. hub slot, 8. wires, 9. horizontal groovings, 10. bases.
Embodiment
The present invention is further illustrated below in conjunction with the accompanying drawings：A kind of end face of collection coal and rock in real time each point vertical stress
Bearing plate, mainly include bolster stake 1, load-carrying ring 2, vertical strain piece 4, horizontal strain piece 6, wire 8 and base 10, bolster stake
1 positioned at positive middle part, and multiple highly equal load-carrying rings 2 are cased with along radial direction bolster stake 1 outside, load-carrying ring 2 it is upper and lower
End face is all in same level, and the central axis of bolster stake 1 and load-carrying ring 2 overlaps, and the number of load-carrying ring 2 being capable of basis
The size of measured rock sample and accordingly increase and decrease, have between adjacent load-carrying ring 2 compensation space 3, existed with adapting to sample end face
The middle and lower part of transversely deforming in compression process, bolster stake 1 and load-carrying ring 2 is provided with the ring of circumferential groove 5, bolster stake 1 and load-carrying ring 2
Horizontal strain piece 6 and vertical strain piece 4, horizontal strain piece 6 and the distribution in pairs of vertical strain piece 4 are distributed with into groove 5, and
And can installing/dismounting, be conveniently replaceable, to ensure the validity of each foil gauge, foil gauge is respectively connected with wire 8, can be by number
According to outflow, the bottom side of load-carrying ring 2 offers hub slot 7, and for concentrating the wire 8 of output, the bottom of load-carrying ring 2 is provided with
Horizontal grooving 9, hub slot 7 and horizontal grooving 9 can mutually coincide on same vertical plane and export wire 8, the He of bolster stake 1
The bottom of load-carrying ring 2 is provided with base 10；
The end face diameter of described bolster stake 1 is 0.5~3 cm, is highly 10~15 cm, the number of described load-carrying ring 2
Measure as 6~10, the ring end surface thickness of load-carrying ring 2 is 0.7~1.5 cm, is highly 10~15 cm, described compensation space
3 width is 2~4 mm, a diameter of 14~24 cm of described base 10, is highly 1~2 cm；
The depth of circumferential groove 5 opened up on described bolster stake 1 and the outer wall of load-carrying ring 2 is 2 mm, to arrange that full-bridge should
Become acquisition system, described vertical strain piece 4 and horizontal strain piece 6 are distributed in circumferential groove 5 at equal intervals, and foil gauge is equal
Wire 8 is connected with, data are spread out of, the fluting of described circumferential groove 5 is highly 2~3 cm, the groove width and height of hub slot 7
Degree is respectively 5 mm and 1~1.5 cm, and the length and height of horizontal grooving 9 are respectively 2~4 cm and 0.5~1 cm；
Wire 8 is connected in turn on static resistance strain acquisition system according to the label of each load-carrying ring 2.
Application method：Bearing plate after completion line is placed on the original bearing plate of servo testing machine, then in this hair
One piece of aluminum sheet is placed on the bearing plate upper surface of bright proposition to prevent the chip after sample crushing to be spilled into compensation space 3
In；Rock sample is placed on bearing plate proposed by the present invention, while vaseline and tristearin are smeared in rock sample upper surface
Acid blend（Mass ratio 1:1）To eliminate the frictional resistance effect on sample upper surface and testing machine between pressure-bearing you face；For quiet
The data that the data and servo testing machine processing system that state resistance-strain acquisition system collects collect are corrected analysis, main
If in order to eliminate the vertical strain of bearing plate of the present invention interference.The end face vertical stress at any place of rock sample end face is equal
Stress on the load-carrying ring 2 contacted with this, i.e.,：σ=E 0 ε 0, whereinE 0For the modulus of elasticity of bearing plate of the present invention,ε 0By answering
Become acquisition system to draw.But the strain of rock sample is then not equal to the strain that servo testing machine processing system collects, and watches
The change in displacement that testing machine detects is taken to be made up of two parts, first come from and rock sample, second be from this
The change in displacement that foil gauge collects on invention bearing plate, then the strain example of rock sample be：
（WhereinhThe change in displacement detected for servo testing machine,h 0For the height of bolster stake 1 or load-carrying ring 2,hFor
The height of rock sample）.
Claims (4)
1. a kind of bearing plate of coal and rock end face of collection in real time each point vertical stress, mainly including bolster stake (1), load-carrying ring (2),
Vertical strain piece (4), horizontal strain piece (6), wire (8) and base (10), it is characterized in that：Bolster stake (1) is positioned at positive middle part, edge
The outside radial direction of bolster stake (1) and be cased with multiple highly equal load-carrying rings (2), load-carrying ring（2）Upper and lower end face all exist
In same level, and the central axis of bolster stake (1) and load-carrying ring (2) overlaps, and the number of load-carrying ring (2) can be according to institute
Measure the size of rock sample and accordingly increase and decrease, there is compensation space (3), bolster stake (1) and carrying between adjacent load-carrying ring (2)
The middle and lower part of ring (2) is provided with circumferential groove (5), and horizontal strain is distributed with the circumferential groove (5) of bolster stake (1) and load-carrying ring (2)
The distribution in pairs of piece (6) and vertical strain piece (4), horizontal strain piece (6) and vertical strain piece (4), foil gauge, which is respectively connected with, leads
Line (8), the bottom side of load-carrying ring (2) offer hub slot (7), and the bottom of load-carrying ring (2) is provided with horizontal grooving (9), collection
Wire casing (7) and horizontal grooving (9) can mutually coincide on same vertical plane and export wire (8), bolster stake (1) and carrying
The bottom of ring (2) is provided with base (10).
2. a kind of bearing plate of end face of collection coal and rock in real time each point vertical stress according to claim 1, its feature exist
In：The end face diameter of described bolster stake (1) is 0.5~3 cm, is highly 10~15 cm, the quantity of described load-carrying ring (2)
For 6~10, the ring end surface thickness of load-carrying ring (2) is 0.7~1.5 cm, is highly 10~15 cm, described compensation space
(3) width is 2~4 mm, a diameter of 14~24 cm of described base (10), is highly 1~2 cm.
3. a kind of bearing plate of end face of collection coal and rock in real time each point vertical stress according to claim 1 or 2, its feature
It is：Circumferential groove (5) depth opened up on described bolster stake (1) and the outer wall of load-carrying ring (2) is 2 mm, to arrange full-bridge
Strain acquisition system, described vertical strain piece (4) and horizontal strain piece (6) are distributed in circumferential groove (5) at equal intervals, and
Foil gauge is respectively connected with wire (8), and data are spread out of, and the fluting of described circumferential groove (5) is highly 2~3 cm, hub slot (7)
Groove width and height be respectively 5 mm and 1~1.5 cm, the length of horizontal grooving (9) and height be respectively 2~4 cm and
0.5~1 cm.
4. a kind of bearing plate of end face of collection coal and rock in real time each point vertical stress according to claim 1, its feature exist
In：Described wire (8) is connected in turn on static resistance strain acquisition system according to the label of each load-carrying ring (2).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510346615.4A CN104897322B (en) | 2015-06-23 | 2015-06-23 | A kind of bearing plate of the end face of collection coal and rock in real time each point vertical stress |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510346615.4A CN104897322B (en) | 2015-06-23 | 2015-06-23 | A kind of bearing plate of the end face of collection coal and rock in real time each point vertical stress |
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| Publication Number | Publication Date |
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| CN104897322A CN104897322A (en) | 2015-09-09 |
| CN104897322B true CN104897322B (en) | 2017-11-14 |
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| CN201510346615.4A Expired - Fee Related CN104897322B (en) | 2015-06-23 | 2015-06-23 | A kind of bearing plate of the end face of collection coal and rock in real time each point vertical stress |
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Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN109870356A (en) * | 2019-01-28 | 2019-06-11 | 北京理工大学 | Multi-channel wide should broaden the propellant compression stress test device of temperature range high security |
| CN116296820B (en) * | 2023-03-31 | 2024-04-05 | 四川大学 | Iterative method for determining rock elasticity parameter and cracking stress by bidirectional approximation and product |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2618538C3 (en) * | 1976-04-28 | 1980-08-21 | Bergwerksverband Gmbh, 4300 Essen | Measuring device for the approximate determination of support forces in mining |
| US4444058A (en) * | 1982-05-28 | 1984-04-24 | The United States Of America As Represented By The United States Department Of Energy | Method and apparatus for determining tensile strength |
| CN100561178C (en) * | 2007-07-13 | 2009-11-18 | 东南大学 | Asphalt concrete elevated temperature property testing method |
| CN103900902A (en) * | 2014-04-16 | 2014-07-02 | 西南科技大学 | Laterally constrained rock uniaxial compression test device |
| CN103983516B (en) * | 2014-06-10 | 2017-02-15 | 山东大学 | Method for measuring and calculating poisson ratio of soil body |
| CN104483199A (en) * | 2014-11-19 | 2015-04-01 | 黄河勘测规划设计有限公司 | Field rock mass poisson ratio test method |
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