CN109085052B - Test method for influences of roof strength on coal seam deformation under action of non-uniform load - Google Patents

Test method for influences of roof strength on coal seam deformation under action of non-uniform load Download PDF

Info

Publication number
CN109085052B
CN109085052B CN201810949230.0A CN201810949230A CN109085052B CN 109085052 B CN109085052 B CN 109085052B CN 201810949230 A CN201810949230 A CN 201810949230A CN 109085052 B CN109085052 B CN 109085052B
Authority
CN
China
Prior art keywords
test piece
coal
test
plate
cavity
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201810949230.0A
Other languages
Chinese (zh)
Other versions
CN109085052A (en
Inventor
刘义鑫
程卫民
王刚
于岩斌
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shandong University of Science and Technology
Original Assignee
Shandong University of Science and Technology
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shandong University of Science and Technology filed Critical Shandong University of Science and Technology
Priority to CN201810949230.0A priority Critical patent/CN109085052B/en
Publication of CN109085052A publication Critical patent/CN109085052A/en
Application granted granted Critical
Publication of CN109085052B publication Critical patent/CN109085052B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N3/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N3/02Details
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N3/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N3/08Investigating strength properties of solid materials by application of mechanical stress by applying steady tensile or compressive forces
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N3/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N3/08Investigating strength properties of solid materials by application of mechanical stress by applying steady tensile or compressive forces
    • G01N3/10Investigating strength properties of solid materials by application of mechanical stress by applying steady tensile or compressive forces generated by pneumatic or hydraulic pressure
    • G01N3/12Pressure testing
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/0014Type of force applied
    • G01N2203/0016Tensile or compressive
    • G01N2203/0019Compressive
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/003Generation of the force
    • G01N2203/0042Pneumatic or hydraulic means
    • G01N2203/0044Pneumatic means

Landscapes

  • Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)

Abstract

The invention discloses a test method for influencing coal seam deformation by roof strength under the action of non-uniform load, which comprises the following steps: the manufacturing test device comprises a concave-shaped seal cavity and a transparent box, wherein a notch part of the seal cavity forms a test piece placing cavity, a front pressing plate is provided with a front pressing rod, the left side, the right side and the rear side of the test piece placing cavity are provided with side pressing plates, the head ends of the side pressing plates are provided with air holes, the side pressing plates are provided with side pressing rods, an upper pressing plate is arranged above an upper backing plate in a front-back adjacent mode, the upper pressing plates are provided with upper pressing rods, and the ends of the upper pressing rods adopt a structure that spherical balls are arranged between two clamping plates; preparing coal powder; preparing a briquette test piece; mounting a briquette test piece; applying a triaxial stress; applying gas pressure; carrying out a test; in the same group of other tests, replacing the upper padding plate with different surface roughness, and re-pressing the briquette test piece with the upper surface matched with the lower surface roughness of the upper padding plate; and (6) collating the test data. Therefore, a triaxial real simulation test of roof strength and coal seam deformation under the action of non-uniform load is carried out.

Description

Test method for influences of roof strength on coal seam deformation under action of non-uniform load
Technical Field
The invention belongs to the technical field of coal mine safety, and particularly relates to a test method for influences of roof strength on coal seam deformation under the action of non-uniform load.
Background
In the coal mining production process, the working face is tunneled to form a local goaf underground, the original stress distribution state and the stress balance of the stratum are damaged, the coal bed is unevenly deformed in the stress redistribution process, and the top plate is sunken and collapsed. The most direct threat generated during roof deformation is rock burst or rock burst, which seriously affects the safe production of coal mine resources in our country. Understanding the formation mechanism and disaster-causing mechanism of rock burst and improving the safety of coal production are important problems in front of related researchers. Therefore, the key factor of roof deformation in the process of working face tunneling is considered as a hand-in point, and the key way of knowing rock burst or rock burst is an important way.
In the tunneling process of the coal bed working face, the top plate does not deform uniformly, and the nonuniform stress distribution of the top plate and the coal bed is caused by the non-uniformity of the stress, so that the permeability characteristic of coal bed gas is influenced, and meanwhile, the nonuniform stress distribution of the coal bed adversely influences the deformation of the top plate and the stress state of the hydraulic support. Therefore, a test for the evolution of the influence of the roof strength on the coal seam deformation and permeability under the action of non-uniform load is carried out, and theoretical support and engineering guidance can be provided for roof support and deep disclosure of a formation mechanism of rock burst and disaster-causing mechanism and risk identification.
At present, domestic and foreign scholars have few researches on the aspect that the roof strength influences the deformation and permeability of a coal bed under the action of non-uniform load, only indoor researches are focused on two-dimensional similarity simulation, the influence of gas pressure is not considered, and an effective test device and method are still lacked for simulating the influence of the roof strength on the deformation and permeability of the coal bed under the action of non-uniform load under the true triaxial stress state, so that the influence of the roof strength and various parameters on the deformation and permeability of the coal body under the true triaxial stress state is researched.
Disclosure of Invention
The invention aims to provide a test method for testing the influence of the roof strength on the coal seam deformation under the action of non-uniform load, which is used for researching the influence of the roof strength on the coal and gas outburst under the true triaxial stress state.
Therefore, the technical scheme adopted by the invention is as follows: a test method for influencing coal seam deformation by roof strength under the action of non-uniform load comprises the following steps:
Step one, manufacturing a test device;
The test device comprises a concave-shaped seal cavity, a notch of the seal cavity faces the front, a transparent box which is equal in height and width to the notch is arranged in front of the seal cavity, the rear part and the top of the transparent box are both open and just connected with the notch, the transparent box and the seal cavity share the same bottom plate, and a plurality of front pressure plates made of transparent materials are arranged between the notch of the seal cavity and the transparent box in a left-right close manner, so that the notch of the seal cavity forms a test piece placing cavity;
Each front pressure plate is provided with a front pressure rod, the front pressure rods penetrate through the transparent box from front to back to be connected with the corresponding front pressure plate, the front pressure rods corresponding to the front pressure plates are independently controlled, and the tunneling speed of the working face is simulated through sequential unloading; the left side, the right side and the rear side of the test piece placing cavity are respectively provided with a side pressing plate, the head end of each side pressing plate is inserted into the corresponding side wall of the sealed cavity, the head end of each side pressing plate is provided with an air hole for communicating the test piece placing cavity with the sealed cavity, each side pressing plate is respectively provided with a side pressing rod, and the side pressing rods penetrate through the sealed cavity from outside to inside and are connected with the tail ends of the side pressing plates; the upper edge of the inner wall of the test piece placing cavity and the transparent box share the same upper base plate, a plurality of upper pressure plates are arranged above the upper base plate in a front-back adjacent mode, each upper pressure plate is provided with an upper pressure rod, the end of each upper pressure rod adopts a structure that a spherical ball is arranged between two clamping plates, the upper pressure rods corresponding to the upper pressure plates are independently controlled, and different loads are applied to reflect the uneven deformation of the coal seam roof under the non-uniform load;
The side wall of the sealed cavity is provided with a fluid inlet hole, and the side wall of the transparent box is provided with a fluid outlet hole;
Step two, preparing coal powder, crushing and grinding raw coal to a required particle size range, screening the ground coal powder through a vibrating screen, and drying for later use;
Step three, preparing a briquette test piece, mixing coal powder according to the particle size ratio, adding a coal powder binder in proportion, stirring uniformly, and filling the coal powder into a mold to press the coal powder into a square briquette test piece;
Step four, mounting a molded coal test piece, and placing the pressed molded coal test piece into a test piece placing cavity of the test device;
Applying triaxial stress, and applying stress to the side pressure rods, the front pressure rod and the upper pressure rod at the left, right and rear parts of the test device to make the briquette test piece be subjected to triaxial constraint;
Step six, applying gas pressure, injecting gas into the test device through the fluid inlet hole, and enabling the gas to enter the molded coal test piece through the air holes in the left side pressure plate, the right side pressure plate and the rear side pressure plate, so that a certain gas pressure is formed in the molded coal test piece, and the next step is performed after the gas injection pressure is kept unchanged;
Step seven, performing a test, namely sequentially withdrawing the front pressing plate from left to right or from right to left in the direction away from the briquette test piece according to the set stress or displacement change rate, obtaining coal seam deformation data by recording the displacement amounts of the left side pressing plate, the right side pressing plate, the rear side pressing plate and the upper pressing plate at different positions, and simultaneously recording the gas flow change of the fluid outlet;
Step eight, replacing the upper base plates with different strengths for other tests in the same group, and repeating the steps four to seven;
And step nine, collating the test data.
Preferably, in step eight, the same set of other tests are performed using upper plates having uniaxial compressive strengths of 30Mpa, 50Mpa and 70Mpa, respectively.
more preferably, in the third step, the briquette test piece is a square block with the size of 600mm × 600mm × 100mm, and correspondingly, in the first step, the test piece placing cavity is also a square cavity with the size of 600mm × 600mm × 100 mm.
More preferably, in the second step, the raw coal is crushed and ground and then dried at 105-110 ℃ for 22-26 hours.
The invention has the beneficial effects that: the stress applied to each pressure plate can truly simulate the triaxial original rock stress state of a coal bed, the gas pressure can be simulated by applying a gas source, the progressive unloading of the front pressure plate simulates the tunneling process of a working face, the unloading speed can simulate the tunneling speed of the working face, the deformation of a briquette test piece is obtained by acquiring the displacement variation of each pressure rod, the real-time visualization of coal and gas outburst can be realized through a transparent material, and by replacing upper base plates with different strengths, the test method for the deformation of the coal bed influenced by the strength of the top plate under the action of non-uniform load is provided, and theoretical support and engineering guidance are provided for the safety production of a coal mine.
Drawings
FIG. 1 is a top view of the test apparatus.
3 fig. 3 2 3 is 3 a 3 cross 3- 3 sectional 3 view 3 a 3- 3 a 3 of 3 fig. 3 1 3. 3
Fig. 3 is a sectional view taken along line B-B of fig. 1.
Fig. 4 is an enlarged view of the end of the upper platen.
The figures are labeled as follows: the device comprises a seal cavity 1, a transparent box 2, a front pressure plate 3, a front pressure rod 4, a bottom plate 5, a test piece placing cavity 6, a side pressure plate 7, a side pressure rod 8, an upper backing plate 9, an upper pressure plate 10, an upper pressure rod 11, a fluid inlet hole 12, a fluid outlet hole 13, a first seal ring 14a, a second seal ring 14b, a third seal ring 14c, a fourth seal gasket 14d, a cover plate 15, a bolt 16 and a molded coal test piece 17.
Detailed Description
The invention will be further illustrated by the following examples in conjunction with the accompanying drawings:
A test method for influencing coal seam deformation by roof strength under the action of non-uniform load comprises the following steps:
Step one, manufacturing a testing device.
Referring to fig. 1-3, the testing device mainly comprises a sealed cavity 1, a transparent box 2, a front pressure plate 3, a front pressure rod 4, a side pressure plate 7, a side pressure rod 8, an upper backing plate 9, an upper pressure plate 10 and an upper pressure rod 11.
The whole sealing cavity 1 is concave, and the notch of the sealing cavity 1 faces the front.
A transparent box 2 with the same height and width as the notch part is arranged in front of the sealed cavity 1. The transparent box 2 is open at the back and the top and is just connected with the notch part. The transparent box 2 and the sealed cavity 1 share the same bottom plate 5, namely the transparent box 2 is only provided with a left side wall, a right side wall and a front side wall. A plurality of front pressing plates 3 made of transparent materials are arranged between the notch part of the seal cavity 1 and the transparent box 2 in a left-right close manner, so that the notch part of the seal cavity 1 forms a test piece placing cavity 6, and the test piece placing cavity 6 is used for placing a briquette test piece 17.
Each front pressing plate 3 is provided with a front pressing rod 4, the front pressing rods 4 penetrate through the transparent box 2 from front to back to be connected with the corresponding front pressing plate 3, the front pressing rods 4 corresponding to the front pressing plates 3 are independently controlled, and the tunneling speed of the working face is simulated through sequential unloading. The front pressing plate 3 and the transparent box 2 are both made of transparent materials, and a tester can observe the crack propagation condition of the surface of the test piece in the test process. The transparent material is especially high strength and toughness transparent polycarbonate plate, and has excellent performance.
The left side, the right side and the rear side of the test piece placing cavity 6 are respectively provided with a side pressing plate 7, the head end of the side pressing plate 7 is inserted into the corresponding side wall of the sealed cavity 1, and the head end of the side pressing plate 7 is provided with an air hole 7a for communicating the test piece placing cavity 6 and the sealed cavity 1. Each side pressure plate 7 is provided with a side pressure rod 8, and the side pressure rods 8 penetrate through the sealed cavity 1 from outside to inside to be connected with the tail ends of the side pressure plates 7. Preferably, the side pressure plate 7 adopts a structure that a vertical parting strip is arranged in a rectangular outer frame, and the vertical parting strip is just staggered with the vent hole 7a, so that fluid in the sealed cavity 1 can enter the test piece placing cavity 6 through the vent hole 7 a.
The upper edges of the inner walls of the test piece placing cavity 6 and the transparent box 2 share the same upper backing plate 9, and a plurality of upper pressure plates 10 are arranged above the upper backing plate 9 in a front-back close mode. Each upper pressure plate 10 is equipped with an upper pressure rod 11, the end of the upper pressure rod 11 adopts a structure (shown in fig. 4) that a spherical ball 11b is installed between two clamping plates 11a, and the upper pressure rod 11 corresponding to each upper pressure plate 10 is independently controlled and reflects the uneven deformation of the coal seam roof under the uneven load by applying different loads. Because the upper pressure plate 10 is arranged by a plurality of blocks, the upper base plate 9 is additionally arranged, the sealing performance of the test piece placing cavity 6 is ensured, and a coal seam roof and a goaf are simulated.
A fluid inlet hole 12 is formed in the side wall of the sealed cavity 1, and fluid is introduced into the sealed cavity 1 through the fluid inlet hole 12; the side wall of the transparent box 2 is provided with a fluid outlet 13, and fluid is discharged through the fluid outlet 13 in the test process. Preferably, the two fluid inlet holes 12 are symmetrically arranged on the rear side wall of the sealed cavity 1; the fluid outlet holes 13 are all arranged on the left side wall or the right side wall of the transparent box 2.
Further, the specimen-placing chamber 6 is preferably a square chamber having the same length and width.
The bottom plate 5 and the cover plate 15 are fixed to the side wall of the sealed cavity 1 by bolts 16. In order to ensure the sealing performance of the test device, a first sealing ring 14a is arranged between the bottom plate 5 and the sealing cavity 1 and between the bottom plate and the test piece placing cavity 6; second sealing rings 14b are arranged between the sealing cavity 1 and the side pressure rod 8 and between the sealing cavity 1 and the side pressure plate 7; a third sealing ring 14c is arranged between the sealing cavity 1 and the cover plate 15; a fourth gasket 14d is disposed between the seal cavity 1 and the upper mat 9.
Preferably, the front pressure lever 4 is in threaded connection with the front pressure plate 3, and the side pressure lever 8 is in threaded connection with the side pressure plate 7, or other fixed connection modes can be adopted.
Preferably, the number of the upper pressing plates 10 is seven, and the upper pressing rod 11 corresponding to each upper pressing plate 10 is controlled by a respective independent control part to reflect the uneven deformation of the coal seam roof; the number of the front pressing plates 3 is six, the front pressing rods 4 corresponding to the front pressing plates 3 are respectively controlled by respective independent control parts, and the tunneling speed of the working face is simulated through sequential unloading.
The test device has the characteristics that:
1. True triaxial stress can be applied from the front and back, the left and right sides and the upper side, the end of the upper pressure plate adopts a structure that a spherical ball is arranged between two clamping plates, and non-uniform load can be applied, so that non-uniform deformation of the top plate is truly simulated.
2. The front pressure plate adopts a structure of combining a plurality of blocks, and the tunneling process of the working face is simulated by gradual unloading; the upper pressure plate adopts a plurality of combined and optimized end head structures of the upper pressure rod, the upper pressure plate is respectively and independently controlled to simulate the loading of non-uniform load of the coal seam roof, and the upper base plate simulates the coal seam roof and a goaf; compared with a manual tunneling mode, the method simulates the actual working condition more truly, and therefore the test precision is improved.
3. The pressure plates on the rear side, the left side and the right side of the test piece are provided with air holes, the test piece can be inflated through the fluid inlet holes to reach certain gas pressure, and the bottom, the front and the upper part of the test piece are provided with no gas source supply holes, so that the actual working condition can be reflected more truly, and the test precision is improved.
4. The test device adopts a sealing structure, and can apply related gas pressure, so that the real working condition is reflected.
And step two, preparing coal powder, crushing and grinding raw coal to a required particle size range, screening the ground coal powder through a vibrating screen, and drying for later use. Preferably, the raw coal is crushed, ground and dried at 105-110 ℃ for 22-26 hours.
And step three, preparing a briquette test piece, namely mixing the coal powder according to the particle size ratio, adding the coal powder binder in proportion, uniformly stirring, and filling the coal powder into a mold to press the coal powder into a square briquette test piece.
preferably, the briquette test piece is a square block of 600mm × 600mm × 100mm, and correspondingly, in the step one, the test piece placing cavity 6 is also a square cavity of 600mm × 600mm × 100 mm.
And step four, mounting the molded coal test piece, and placing the pressed molded coal test piece into the test piece placing cavity 6 of the test device.
And fifthly, applying triaxial stress to apply stress to the left, right and rear side compression bars 8, the front compression bar 4 and the upper compression bar 11 of the test device, so that the molded coal test piece is subjected to triaxial constraint.
And sixthly, applying gas pressure, injecting gas into the test device through the fluid inlet holes 12, and enabling the gas to enter the molded coal test piece through the air holes 7a in the left side pressure plate, the right side pressure plate and the rear side pressure plate 7, so that a certain gas pressure is formed in the molded coal test piece, and the molded coal test piece enters the next step after the gas injection pressure is kept unchanged. When there are two fluid inlet holes 12, gas is simultaneously injected into the test device through the two fluid inlet holes 12.
And seventhly, performing a test, namely sequentially withdrawing the front pressing plate 3 from left to right or from right to left according to the set stress or displacement change rate to the direction far away from the briquette coal test piece, recording the displacement of the left, right and rear side pressing plates 7 and the upper pressing plate 10 at different positions to obtain coal seam deformation data, and simultaneously recording the gas flow change of the fluid outlet hole 13.
And step eight, replacing the upper backing plate 9 with different strengths for other tests in the same group, and repeating the steps from four to seven. The same set of other tests is preferably carried out using the upper plate 9 having uniaxial compressive strengths of 30MPa, 50MPa and 70MPa, respectively.
For example, coal powder with different particle sizes is prepared by mixing coal powder with a particle size of less than 40 meshes: 40-60 mesh: 60-80 meshes: 80-100 meshes: mixing the materials in a mass ratio of more than 100 meshes to 1:1:1:1, adding 5% of milk white glue as a bonding agent, pressing the mixture into a briquette test piece, and performing repeated tests according to the following table:
Figure BDA0001771061260000081
The relationship between the roof strength and the coal seam deformation under the action of the non-uniform load can be researched by repeating the test shown in the table.

Claims (4)

1. A test method for testing influence of roof strength on coal seam deformation under the action of non-uniform load is characterized by comprising the following steps:
Step one, manufacturing a test device;
The test device comprises a concave-shaped seal cavity (1), a notch of the seal cavity (1) faces the front, a transparent box (2) which is equal in height and width to the notch is arranged in front of the seal cavity (1), the rear part and the top part of the transparent box (2) are both open and just connected with the notch, the transparent box (2) and the seal cavity (1) share the same bottom plate (5), and a plurality of front pressure plates (3) made of transparent materials are arranged between the notch of the seal cavity (1) and the transparent box (2) in a left-right close manner, so that the notch of the seal cavity (1) forms a test piece placing cavity (6);
Each front pressure plate (3) is provided with a front pressure rod (4), the front pressure rods (4) penetrate through the transparent box (2) from front to back to be connected with the corresponding front pressure plate (3), the front pressure rods (4) corresponding to each front pressure plate (3) are independently controlled, and the tunneling speed of a working face is simulated through sequential unloading; the left side, the right side and the rear side of the test piece placing cavity (6) are respectively provided with a side pressing plate (7), the head end of each side pressing plate (7) is inserted into the corresponding side wall of the sealed cavity (1), the head end is provided with an air hole (7a) for communicating the test piece placing cavity (6) with the sealed cavity (1), each side pressing plate (7) is respectively provided with a side pressing rod (8), and each side pressing rod (8) penetrates through the sealed cavity (1) from outside to inside to be connected with the tail end of each side pressing plate (7); the test piece placing cavity (6) and the upper edge of the inner wall of the transparent box (2) share the same upper base plate (9), a plurality of upper pressure plates (10) are arranged above the upper base plate (9) in a front-back adjacent mode, each upper pressure plate (10) is provided with an upper pressure rod (11), the end of each upper pressure rod (11) adopts a structure that a spherical ball (11b) is arranged between two clamping plates (11a), the upper pressure rods (11) corresponding to the upper pressure plates (10) are independently controlled, and different loads are applied to reflect the uneven deformation of the coal seam roof under the non-uniform load;
A fluid inlet hole (12) is formed in the side wall of the sealed cavity (1), and a fluid outlet hole (13) is formed in the side wall of the transparent box (2);
Step two, preparing coal powder, crushing and grinding raw coal to a required particle size range, screening the ground coal powder through a vibrating screen, and drying for later use;
Step three, preparing a briquette test piece, mixing coal powder according to the particle size ratio, adding a coal powder binder in proportion, stirring uniformly, and filling the coal powder into a mold to press the coal powder into a square briquette test piece;
Step four, mounting a molded coal test piece, and placing the pressed molded coal test piece into a test piece placing cavity (6) of the test device;
Applying triaxial stress, and applying stress to the left, right and rear side pressure rods (8), the front pressure rod (4) and the upper pressure rod (11) of the test device to make the briquette test piece be subjected to triaxial constraint;
Step six, applying gas pressure, injecting gas into the test device through the fluid inlet holes (12), and enabling the gas to enter the molded coal test piece through the air holes (7a) on the left side pressure plate, the right side pressure plate and the rear side pressure plate (7), so that a certain gas pressure is formed in the molded coal test piece, and the molded coal test piece enters the next step after the gas injection pressure is kept unchanged;
Seventhly, performing a test, namely sequentially withdrawing the front pressing plate (3) from left to right or from right to left in the direction away from the briquette test piece according to the set stress or displacement change rate, obtaining coal seam deformation data by recording the displacement of the left side pressing plate, the right side pressing plate, the rear side pressing plate (7) and the upper pressing plate (10) at different positions, and simultaneously recording the gas flow change of the fluid outlet hole (13);
Step eight, replacing the upper backing plate (9) with different strength in other tests in the same group, and repeating the steps four to seven;
And step nine, collating the test data.
2. The test method for the deformation of the coal seam influenced by the roof strength under the action of the non-uniform load according to claim 1, which is characterized in that: and step eight, performing the same group of other tests by adopting the upper backing plate (9) with the uniaxial compressive strength of 30Mpa, 50Mpa and 70Mpa respectively.
3. the test method for testing the influence of the roof strength on the coal seam deformation under the action of the non-uniform load is characterized in that in the third step, the briquette coal test piece is a square block with the size of 600mm multiplied by × 100mm, and correspondingly, in the first step, the test piece placing cavity (6) is a square cavity with the size of 600mm multiplied by × 100 mm.
4. The test method for the deformation of the coal seam influenced by the roof strength under the action of the non-uniform load according to claim 1, which is characterized in that: in the second step, the raw coal is dried for 22-26 hours at 105-110 ℃ after being crushed and ground.
CN201810949230.0A 2018-08-20 2018-08-20 Test method for influences of roof strength on coal seam deformation under action of non-uniform load Active CN109085052B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201810949230.0A CN109085052B (en) 2018-08-20 2018-08-20 Test method for influences of roof strength on coal seam deformation under action of non-uniform load

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201810949230.0A CN109085052B (en) 2018-08-20 2018-08-20 Test method for influences of roof strength on coal seam deformation under action of non-uniform load

Publications (2)

Publication Number Publication Date
CN109085052A CN109085052A (en) 2018-12-25
CN109085052B true CN109085052B (en) 2020-07-17

Family

ID=64793849

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201810949230.0A Active CN109085052B (en) 2018-08-20 2018-08-20 Test method for influences of roof strength on coal seam deformation under action of non-uniform load

Country Status (1)

Country Link
CN (1) CN109085052B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111103187B (en) * 2019-12-04 2022-04-19 太原理工大学 Method for predicting breaking impact strength of key layers at different layers

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4043568B2 (en) * 1997-11-19 2008-02-06 財団法人電力中央研究所 In-situ hole bottom triaxial compression test method
CN106840810A (en) * 2017-04-12 2017-06-13 中国地质大学(武汉) A kind of ring shear test and preparation of soil sample device suitable for vertical shearing face
CN108007781A (en) * 2017-11-17 2018-05-08 山东科技大学 Roadway support mechanics simulation experiment system and its method under sound combined load
CN108124460A (en) * 2017-04-28 2018-06-05 山东大学 Intelligent numerical control super-pressure is very three-dimensional non-homogeneous plus unloads and voltage stabilizing model assay systems
CN207649998U (en) * 2017-12-27 2018-07-24 西南交通大学 Tunnel lining structure non-uniform load dynamic characteristic test apparatus

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4043568B2 (en) * 1997-11-19 2008-02-06 財団法人電力中央研究所 In-situ hole bottom triaxial compression test method
CN106840810A (en) * 2017-04-12 2017-06-13 中国地质大学(武汉) A kind of ring shear test and preparation of soil sample device suitable for vertical shearing face
CN108124460A (en) * 2017-04-28 2018-06-05 山东大学 Intelligent numerical control super-pressure is very three-dimensional non-homogeneous plus unloads and voltage stabilizing model assay systems
CN108007781A (en) * 2017-11-17 2018-05-08 山东科技大学 Roadway support mechanics simulation experiment system and its method under sound combined load
CN207649998U (en) * 2017-12-27 2018-07-24 西南交通大学 Tunnel lining structure non-uniform load dynamic characteristic test apparatus

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
黏结剂含量对含瓦斯煤剪切细观损伤力学特性影响的试验研究;程立朝等;《岩土力学》;20150930;第2467-2476页 *

Also Published As

Publication number Publication date
CN109085052A (en) 2018-12-25

Similar Documents

Publication Publication Date Title
CN109142026B (en) Coal body deformation test method under coal seam water injection fracturing influence mining action
CN109142053B (en) Coal body outburst test method under coal seam permeability influence mining action
CN109142027B (en) Visual test method for coal seam outburst caused by face excavation
CN109991108B (en) Simulation test method for metal framework reinforced coal and gas outburst under action of dynamic and static loads
CN109991391B (en) Simulation test method for coal and gas outburst of fault-containing coal series rock layer
CN108918249B (en) Coal body deformation test method under coal seam water injection wetting influence mining action
CN111175468B (en) Pressure-relief and impact-prevention test method for water-injection-wetted coal rock under true three-dimensional stress
CN109900543B (en) Two-dimensional combined stress induction protrusion simulation test device
CN107165624A (en) Fractured-cavernous carbonate reservoir three-dimensional large scale physical model and preparation method thereof
CN108871905B (en) Test method for influence of bedding surface roughness on deformation and permeability of mining coal seam
CN109060507B (en) Method for testing influence of coal bed gas extraction on deformation of coal bed roof under action of non-uniform load
CN111175470B (en) Test method for simulating spontaneous combustion and instability of coal body under true triaxial stress
CN109085052B (en) Test method for influences of roof strength on coal seam deformation under action of non-uniform load
CN107255700B (en) Coal bed gas well discharge and production process pulverized coal output simulation test device and test method thereof
CN109100212B (en) Test method for influence of working face tunneling speed on coal body deformation
CN104698138A (en) Microseismic response coal and gas outburst self-triggering simulation experiment device
CN116087468B (en) Comprehensive test method for strength, strain and seepage of oil sand in high-temperature stress environment
CN109916730B (en) Two-dimensional dynamic and static combined loading analog simulation test method
CN109142028B (en) Coal seam deformation test device caused by working face tunneling
CN111579343A (en) Coal rock forming experimental device and method for testing three-dimensional apparent resistivity change
CN111272633A (en) Test method for influencing permeability and wetting effect of coal seam by borehole deformation
CN108507922B (en) Test method for rock mass grouting seepage and reinforcement characteristics under yielding anchor grouting coupling support
CN116086974A (en) Simulation test method for punching fracturing multiple coal beds under true triaxial stress
CN110441147B (en) Physical simulation device and simulation method for circumferential compression of coal mine vertical shaft wall
CN204630996U (en) Microseismic response coal and gas outburst self-triggering simulation experiment device

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant