Coal and gas outburst test device and method for simulating different coal-rock contact surfaces

Abstract

The invention discloses a coal and gas outburst test device and method for simulating different coal-rock contact surfaces, and the device comprises a box body, one side of the box body is movably connected with a movable baffle plate, a coal sample is arranged in the box body, the top of the coal sample is provided with a top plate rock sample, the bottom of the coal sample is provided with a bottom plate rock sample, the top of the box body is provided with a loading mechanism, and one side of the box body is provided with a gas filling mechanism. A monitoring mechanism is arranged in the box body, and the monitoring mechanism and the loading mechanism are electrically connected with the control mechanism. The loading mechanism is used for controlling the axial pressure and the confining pressure of a coal rock layer, and the baffle, the box body and the loading device can form a sealing structure, so that the air tightness of the box body in the test process can be guaranteed; the baffle can move in multiple directions along the sliding rail, and the moving speed is controllable, so that different coal uncovering directions and coal uncovering speeds are simulated.

Description

Technical Field

[0001] The invention belongs to the technical field of coal mine safety, and in particular relates to a coal and gas outburst test device and method for simulating contact surfaces of different coals and rocks. Background Art

[0002] Coal and gas outburst is a serious threat to coal mine safety production. It refers to the phenomenon that when the stability of the coal sample is destroyed, the gas and coal powder stored in the coal sample suddenly gush into the tunnel or mining area in a very short time. It has obvious dynamic effects and causes serious damage to the life safety of miners and the equipment of the mine.

[0003] At present, the research on coal and gas outbursts often focuses on the coal body itself and the role of gas. However, the occurrence of outbursts is the result of the combined action of coal, gas and surrounding rock. In the research on coal and gas outbursts, the friction of surrounding rock (roof and floor) on coal samples is usually ignored, which is obviously unreasonable. Then, what is the effect of the friction of the coal-rock contact surface on the outburst, and what is the relationship between the coal-rock contact surface with different friction during the outburst and the critical gas pressure and the characteristics of gas pressure change, all of which need to be studied in depth. Summary of the invention

[0004] The purpose of the present invention is to provide a coal and gas outburst test device and method for simulating different coal-rock contact surfaces, so as to solve the problems existing in the above-mentioned prior art.

[0005] To achieve the above-mentioned purpose, the present invention provides the following scheme: The present invention provides a coal and gas outburst test device that simulates different coal-rock contact surfaces, including a box body, a movable baffle movably connected to one side of the box body, a coal sample is arranged in the box body, a roof rock sample is arranged on the top of the coal sample, and a bottom rock sample is arranged on the bottom of the coal sample, a loading mechanism is arranged on the top of the box body, a gas filling mechanism is arranged on one side of the box body, a monitoring mechanism is arranged in the box body, and the monitoring mechanism and the loading mechanism are electrically connected to the control mechanism respectively.

[0006] Preferably, the monitoring mechanism includes a first sensor arranged in the roof rock sample, a second sensor arranged in the coal sample, and a third sensor arranged in the floor rock sample, and the first sensor, the second sensor and the third sensor are electrically connected to the control mechanism respectively.

[0007] Preferably, the gas filling mechanism comprises a gas injection port arranged on the box body, and the gas injection port is connected to a high-pressure gas cylinder and a vacuum pump respectively.

[0008] Preferably, the control mechanism is a computer, and the first sensor, the second sensor, the third sensor and the loading mechanism are electrically connected to the computer respectively.

[0009] Preferably, a damper is provided outside the baffle.

[0010] The test method for simulating coal and gas outburst at different coal-rock interfaces comprises the following steps:

[0011] S1: Take coal blocks and rocks on site and prepare coal samples, roof rock samples and floor rock samples;

[0012] S2: Processing the coal sample, roof rock sample and bottom rock sample in S1, grinding the contact surfaces of the prepared coal sample, roof rock sample and bottom rock sample, then measuring the friction force of the coal-rock contact surface, and loading the processed coal sample, roof rock sample and bottom rock sample into the box;

[0013] S3: Start the loading mechanism to load the roof rock sample, floor rock sample and coal sample;

[0014] S4: Turn on the vacuum pump to evacuate the box, and then inject gas into the coal layer to a predetermined pressure and fully adsorb it;

[0015] S5: Move the movable baffle according to the test requirements to make the coal sample protrude, and measure the values ​​of various parameters through the monitoring mechanism;

[0016] S6: Collect data, analyze and process data, clean the coal and rock layers in the box, and prepare for the next test.

[0017] Preferably, in S2, the surfaces of the coal sample, the roof rock sample and the floor rock sample are treated by sandpaper or by adding an industrial adhesive.

[0018] The present invention discloses the following technical effects: the present invention can simulate the friction between the contact surfaces of different coal samples and rock formations in a mine, and the test parameters such as stress, gas pressure and friction between the contact surfaces of coal and rock formations in the present invention can be adjusted according to the test needs, and the coal and gas outburst test can be carried out by inducing outburst. The test can explore the influence of factors such as friction between coal and rock, heat generated by friction and gas distribution on coal and gas outburst, and can also explore the coal-rock temperature, critical stress of gas and deformation characteristics of coal and rock formations when outburst occurs at coal-rock contact surfaces with different friction. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0020] Figure 1 It is a schematic diagram of the structure of the coal and gas outburst test device for simulating different coal-rock contact surfaces of the present invention;

[0021] Figure 2This is a schematic diagram of a protrusion test when the baffle of the present invention moves upward;

[0022] Figure 3 This is a test schematic diagram of the present invention when the baffle is lifted up;

[0023] Figure 4 This is a schematic diagram of the structure of Embodiment 2 of the present invention;

[0024] In the figure: 1. box body; 2. bottom plate rock sample; 3. coal sample; 4. roof plate rock sample; 5. loading mechanism; 6. gas injection hole; 7. first sensor; 8. second sensor; 9. third sensor; 10. movable baffle; 11. high-pressure gas cylinder; 12. computer; 13. vacuum pump; 14. first grouting borehole; 15. second grouting borehole; 16. third grouting borehole; 17. fourth grouting borehole. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0027] Example 1

[0028] Reference Figure 1-Figure 3 As shown, the present embodiment provides a coal and gas outburst test device simulating different coal-rock contact surfaces, including a box body 1, a movable baffle 10 movably connected to one side of the box body 1, a coal sample 3 is arranged in the box body 1, a roof rock sample 4 is arranged on the top of the coal sample 3, a bottom rock sample 2 is arranged on the bottom of the coal sample 3, a loading mechanism 5 is arranged on the top of the box body 1, a gas filling mechanism is arranged on one side of the box body 1, a monitoring mechanism is arranged in the box body 1, and the monitoring mechanism and the loading mechanism 5 are electrically connected to the control mechanism respectively.

[0029] The loading mechanism 5 is used to control the axial pressure and confining pressure of the coal rock layer. The baffle, the box 1 and the loading device can form a sealing structure to ensure the air tightness of the box 1 during the test. The baffle can move in multiple directions along the slide rail, and the moving speed is controllable to simulate different coal uncovering directions and speeds.

[0030] The present invention can simulate the friction between the contact surface of different coal samples 3 and the rock layer in the mine. The test parameters such as stress, gas pressure and friction between the contact surface of coal and rock layer in the present invention can be adjusted according to the test needs, and the coal and gas outburst test can be carried out by inducing outburst. The test can explore the influence of factors such as friction between coal and rock, heat generated by friction and gas distribution on coal and gas outburst, and can also explore the coal rock temperature, critical stress of gas and deformation characteristics of coal and rock layer when outburst occurs at the coal rock contact surface with different friction.

[0031] According to a further optimized solution, the monitoring mechanism includes a first sensor 7 arranged in the roof rock sample 4, a second sensor 8 arranged in the coal sample 3 and a third sensor 9 arranged in the bottom rock sample 2. The first sensor 7, the second sensor 8 and the third sensor 9 are electrically connected to the control mechanism respectively.

[0032] According to a further optimized solution, the gas filling mechanism includes a gas injection port arranged on the box body 1, and the gas injection port is connected to the high-pressure gas cylinder 11 and the vacuum pump 13 respectively.

[0033] According to a further optimized solution, the control mechanism is a computer 12 , and the first sensor 7 , the second sensor 8 , the third sensor 9 and the loading mechanism 5 are electrically connected to the computer 12 respectively.

[0034] To further optimize the solution, a damper is provided outside the baffle. The damper can provide different resistances, and the baffle can be pushed outward when it protrudes. The pushing-out situation is used to simulate the damage of the coal mining face when it protrudes.

[0035] The sizes of the top and bottom plates and the coal sample 3 filled in the box 1 are controllable, and the ratio of the coal sample 3 to the rock sample in the box 1 can be adjusted according to the test needs, so as to achieve the test purpose of only studying the contact surface between the top plate rock sample 4 and the coal sample 3, or only studying the contact surface between the bottom plate rock sample 2 and the coal sample 3.

[0036] Explosives can be pre-laid in the rock mass and then detonated to actively induce coal and gas outbursts by destroying the coal-rock strata through dynamic load disturbance. This is to explore the impact of engineering disturbances on coal-rock contact surfaces with different frictional forces and outbursts during mine mining. It is also possible to observe the damage of coal-rock contact surfaces with different frictional forces caused by different disturbance conditions (explosive energy).

[0037] The test method for simulating coal and gas outburst at different coal-rock interfaces comprises the following steps:

[0038] S1: Take coal blocks and rocks on site and prepare coal sample 3, roof rock sample 4 and floor rock sample 2;

[0039] S2: Process the coal sample 3, the roof rock sample 4 and the bottom rock sample 2 in S1, grind the contact surfaces of the prepared coal sample 3, the roof rock sample 4 and the bottom rock sample 2, then measure the friction force of the coal-rock contact surface, and load the processed coal sample 3, the roof rock sample 4 and the bottom rock sample 2 into the box 1;

[0040] S3: Start the loading mechanism 5 to load the roof rock sample 4, the floor rock sample 2 and the coal sample 3;

[0041] S4: Turn on the vacuum pump 13 to evacuate the inside of the box 1, and then inject gas into the coal layer to a predetermined pressure and fully adsorb it;

[0042] S5: according to the test requirements, the movable baffle 10 is moved to make the coal sample 3 protrude, and the values ​​of various parameters are measured by the monitoring mechanism;

[0043] S6: Collect data, analyze and process data, clean the coal and rock layers in box 1, and prepare for the next test.

[0044] To further optimize the solution, in S2, the surfaces of the coal sample 3, the roof rock sample 4 and the floor rock sample 2 are processed by sandpaper or by adding industrial adhesives.

[0045] Example 2

[0046] Reference Figure 4 When conducting the anti-burst test, after the loading mechanism 5 on the box 1 is lifted, the first grouting borehole 14, the second grouting borehole 15, the third grouting borehole 16, and the fourth grouting borehole 17 are equally spaced between the roof rock sample 4 and the coal sample 3, and solidifiable slurry is injected into the above boreholes respectively to achieve the effect of artificially reinforcing the top coal, so as to carry out the artificial anti-burst test and explore the effect of drilling grouting to prevent bursts under different conditions.

[0047] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0048] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A coal and gas outburst test device simulating different coal-rock contact surfaces, characterized by: The invention comprises a box body (1), one side of which is movably connected to a movable baffle (10), a coal sample (3) is arranged in the box body (1), a top plate rock sample (4) is arranged on the top of the coal sample (3), a bottom plate rock sample (2) is arranged on the bottom of the coal sample (3), a loading mechanism (5) is arranged on the top of the box body (1), a gas filling mechanism is arranged on one side of the box body (1), a monitoring mechanism is arranged in the box body (1), and the monitoring mechanism and the loading mechanism (5) are respectively electrically connected to a control mechanism.

2. The coal and gas outburst test device for simulating different coal-rock contact surfaces according to claim 1, characterized in that: The monitoring mechanism comprises a first sensor (7) arranged in the roof rock sample (4), a second sensor (8) arranged in the coal sample (3), and a third sensor (9) arranged in the floor rock sample (2); the first sensor (7), the second sensor (8), and the third sensor (9) are electrically connected to the control mechanism respectively.

3. The coal and gas outburst test device for simulating different coal-rock contact surfaces according to claim 1, characterized in that: The gas filling mechanism comprises a gas injection port arranged on the box body (1), and the gas injection port is respectively connected to the high-pressure gas cylinder (11) and the vacuum pump (13).

4. The coal and gas outburst test device for simulating different coal-rock contact surfaces according to claim 2, characterized in that: The control mechanism is a computer (12), and the first sensor (7), the second sensor (8), the third sensor (9) and the loading mechanism (5) are electrically connected to the computer (12) respectively.

5. The coal and gas outburst test device for simulating different coal-rock contact surfaces according to claim 1, characterized in that: A damper is arranged outside the baffle.

6. A test method for simulating coal and gas outburst at different coal-rock interfaces, based on a test device for simulating coal and gas outburst at different coal-rock interfaces as claimed in any one of claims 1 to 5, characterized in that: The following steps are involved: S1: Take coal blocks and rocks from the site and prepare coal samples (3), roof rock samples (4) and floor rock samples (2); S2: Processing the coal sample (3), the roof rock sample (4) and the bottom rock sample (2) in S1, grinding the contact surfaces of the prepared coal sample (3), the roof rock sample (4) and the bottom rock sample (2), then measuring the friction force of the coal-rock contact surface, and loading the processed coal sample (3), the roof rock sample (4) and the bottom rock sample (2) into the box (1); S3: starting the loading mechanism (5) to load the roof rock sample (4), the floor rock sample (2) and the coal sample (3); S4: starting the vacuum pump (13) to evacuate the inside of the box (1), and then injecting gas into the coal layer to a predetermined pressure and fully adsorbing the gas; S5: according to the test requirements, the movable baffle (10) is moved to make the coal sample (3) protrude, and the values ​​of various parameters are measured by the monitoring mechanism; S6: Collect data, analyze and process data, clean the coal layer in the box (1), and prepare for the next test.

7. The test method for simulating coal and gas outburst at different coal-rock interfaces according to claim 6, characterized in that: In S2, the surfaces of the coal sample (3), the roof rock sample (4) and the floor rock sample (2) are processed by sandpaper or by adding industrial adhesives.

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