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

Abstract

The application discloses a coal and gas outburst test device and method for simulating different coal rock contact surfaces, which comprises a box body, a movable baffle movably connected to one side of the box body, a coal sample arranged in the box body, a top rock sample arranged on the top of the coal sample, a bottom rock sample arranged on the bottom of the coal sample, a loading mechanism arranged on the top of the box body, an air feeding mechanism arranged on one side of the box body, a monitoring mechanism arranged in the box body, and a control mechanism electrically connected with the monitoring mechanism and the loading mechanism. The loading mechanism is used for controlling the axial pressure and the confining pressure of the coal rock layer. The baffle, the box body and the loading device can form a sealed structure, so that the air tightness of the box body during the test process can be ensured. The baffle can move in multiple directions along a sliding rail, and the moving speed is controllable, so that different coal uncovering directions and coal uncovering speeds can be simulated.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of coal mine safety, and particularly relates to a coal and gas outburst test device and method for simulating different coal-rock contact surfaces. BACKGROUND

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

[0003] At present, the research on coal and gas outburst often focuses on the coal body itself and the role of gas, however, the outburst is the result of the joint action of coal, gas and surrounding rock. It is obviously unreasonable to ignore the friction of surrounding rock (roof and floor) on the coal sample in the research on coal and gas outburst. Therefore, the influence of the friction of the coal-rock contact surface on the outburst, and the relationship between the coal-rock contact surface with different friction and the critical gas pressure and the change characteristics of the gas pressure during the outburst need to be further studied. SUMMARY

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

[0005] To achieve the above purpose, the present application provides the following scheme: the present application provides a coal and gas outburst test device for simulating different coal-rock contact surfaces, which comprises a box body, a movable baffle movably connected to one side of the box body, a coal sample arranged in the box body, a roof rock sample arranged on the top of the coal sample, a floor rock sample arranged on the bottom of the coal sample, a loading mechanism arranged on the top of the box body, a gas adding mechanism arranged on one side of the box body, a monitoring mechanism arranged in the box body, and a control mechanism electrically connected to the monitoring mechanism and the loading mechanism.

[0006] Preferably, the monitoring mechanism comprises 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.

[0007] Preferably, the gas adding mechanism comprises a gas injection port arranged on the box body, and the gas injection port is in communication with a high-pressure gas cylinder and a vacuum pump.

[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.

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

[0010] The test method for simulating coal and gas outburst of different coal and rock contact surfaces comprises the following steps:

[0011] S1: taking field coal and rock blocks, preparing coal samples, roof rock samples and floor rock samples;

[0012] S2: processing the coal samples, roof rock samples and floor rock samples in S1, polishing the contact surfaces of the prepared coal samples, roof rock samples and floor rock samples, then measuring the friction of the coal and rock contact surfaces, and loading the processed coal samples, roof rock samples and floor rock samples into the box;

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

[0014] S4: starting the vacuum pump to perform vacuumizing treatment on the box, then injecting gas into the coal and rock layer to a predetermined pressure and fully adsorbing;

[0015] S5: moving the movable baffle according to the test needs to make the coal sample outburst, and measuring the parameter values through the monitoring mechanism;

[0016] S6: collecting data, analyzing and processing the data, cleaning the coal and rock layer in the box, and preparing for the next test.

[0017] Preferably, the surfaces of the coal samples, roof rock samples and floor rock samples are processed through sandpaper or adding industrial adhesives in S2.

[0018] The present application can simulate the friction conditions of the contact surfaces between different coal samples and rock layers in a mine, and the test parameters such as the stress, gas pressure and friction between the coal and rock layer contact surfaces in the present application can be adjusted according to the test needs, and the coal and gas outburst test can be performed through induced outburst. The test can explore the influence of the friction between coal and rock, heat generated by friction and gas distribution on coal and gas outburst, and can also explore the coal and rock temperature, critical stress of gas and deformation characteristics of the coal and rock layer when the coal and rock contact surface with different friction sizes outbursts. BRIEF DESCRIPTION OF DRAWINGS

[0019] The accompanying drawings, which form a part of this application, are included to provide a further understanding of the application and are incorporated in and constitute a part of this application. The embodiments illustrated in the drawings, and their description, are presented to explain the application and not to limit or define it. In the drawings:

[0020] Figure 1 Fig. 1 is a structural schematic view of a coal and gas outburst test device for simulating different coal and rock contact surfaces according to the present application;

[0021] Figure 2A schematic diagram of the projection test when the baffle of the present application moves upward;

[0022] Figure 3 A schematic diagram of the test when the baffle of the present application is lifted;

[0023] Figure 4 A schematic diagram of the structure of embodiment 2 of the present application;

[0024] In the figure: 1, box; 2, floor rock sample; 3, coal sample; 4, roof 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 technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

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

[0027] Embodiment 1

[0028] Referring to Figures 1-3 The present embodiment provides a coal and gas outburst test device for simulating different coal-rock contact surfaces, which comprises a box 1, a movable baffle 10 movably connected to one side of the box 1, a coal sample 3 arranged in the box 1, a roof rock sample 4 arranged on the top of the coal sample 3, a floor rock sample 2 arranged on the bottom of the coal sample 3, a loading mechanism 5 arranged on the top of the box 1, a gas injection mechanism arranged on one side of the box 1, a monitoring mechanism arranged in the box 1, and a control mechanism electrically connected to the monitoring mechanism and the loading mechanism 5.

[0029] The loading mechanism 5 is used for controlling the axial pressure and confining pressure of the coal-rock layer. The baffle, the box 1 and the loading device can form a sealed structure, which can guarantee 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, so as to simulate different coal uncovering directions and coal uncovering speeds.

[0030] The present application can simulate the friction force between different coal samples 3 and rock strata, and the test parameters such as stress, gas pressure and friction force between the coal and rock strata 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 friction force between coal and rock, heat generated by friction and gas distribution on coal and gas outburst, and can also explore the coal and rock temperature, critical stress of gas and deformation characteristics of coal and rock strata of the coal and rock contact surface with different friction force when outburst occurs.

[0031] Further optimization scheme, the monitoring mechanism includes the first sensor 7 arranged in the roof rock sample 4, the second sensor 8 arranged in the coal sample 3 and the third sensor 9 arranged in the floor rock sample 2, and the first sensor 7, the second sensor 8 and the third sensor 9 are respectively electrically connected with the control mechanism.

[0032] Further optimization scheme, the gas injection mechanism includes a gas injection port arranged on the box body 1, and the gas injection port is communicated with the high-pressure gas cylinder 11 and the vacuum pump 13.

[0033] Further optimization scheme, 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 respectively electrically connected with the computer 12.

[0034] Further optimization scheme, the baffle is provided with a damper. The damper can provide different resistance, and the baffle can be pushed outward when outburst occurs, and the pushed-out condition is used to simulate the damage condition of the coal uncovering face when outburst occurs.

[0035] The size of the roof and floor and the coal sample 3 filled in the box body 1 is controllable, and the ratio of the coal sample 3 and the rock sample in the box body 1 can be adjusted according to the test needs. In order to achieve the test purpose of only studying the contact surface between the roof rock sample 4 and the coal sample 3 or only studying the contact surface between the floor rock sample 2 and the coal sample 3.

[0036] Explosives can be laid in the rock mass in advance, and then detonated, and the coal and gas outburst can be induced by dynamic load disturbance to damage the coal and rock strata, so as to explore the influence of engineering disturbance on the coal and rock contact surface with different friction force and outburst situation, and also can observe the damage of the coal and rock contact surface with different friction force under different disturbance (explosive energy).

[0037] The test method for simulating coal and gas outburst of different coal and rock contact surfaces comprises the following steps:

[0038] S1: taking on-site coal and rock blocks, preparing coal sample 3, roof rock sample 4 and floor rock sample 2;

[0039] S2: processing the coal sample 3, the roof rock sample 4 and the floor rock sample 2 in S1, polishing the contact surface of the prepared coal sample 3, the roof rock sample 4 and the floor rock sample 2, then measuring the friction of the coal rock contact surface, and loading the processed coal sample 3, the roof rock sample 4 and the floor rock sample 2 into the box 1;

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

[0041] S4: starting the vacuum pump 13 to perform vacuumizing treatment on the box 1, then injecting gas into the coal rock layer to a predetermined pressure and fully adsorbing;

[0042] S5: moving the movable baffle 10 according to the test requirement, so that the coal sample 3 protrudes, and measuring the parameter values through the monitoring mechanism;

[0043] S6: collecting data, analyzing and processing the data, cleaning the coal rock layer in the box 1, and preparing for the next test.

[0044] Further optimization scheme, in S2, the surface of the coal sample 3, the roof rock sample 4 and the floor rock sample 2 is treated by sandpaper or adding industrial adhesive.

[0045] Embodiment 2

[0046] Reference Figure 4 When the outburst prevention test is performed, when the loading mechanism 5 on the box 1 is lifted, the first grouting drill hole 14, the second grouting drill hole 15, the third grouting drill hole 16 and the fourth grouting drill hole 17 are arranged at equal intervals between the roof rock sample 4 and the coal sample 3, and the above drill holes are respectively injected with solidifiable slurry, so as to achieve the effect of artificially reinforcing the top coal, so as to perform artificial outburst prevention test and explore the effect of drill hole grouting outburst prevention under different conditions.

[0047] In the description of the present application, it should be understood that the orientations or positional relationships indicated by the terms "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present application, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore cannot be understood as a limitation on the present application.

[0048] The above-described embodiments are only descriptions of the preferred modes of the present application, and do not limit the scope of the present application, and various modifications and improvements to the technical solutions of the present application made by those skilled in the art without departing from the design spirit of the present application shall fall within the protection scope determined by the claims of the present application.

Claims

1. A coal and gas outburst test device simulating different coal-rock interfaces, 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) being arranged in the box body (1), a top plate rock sample (4) being arranged on the top of the coal sample (3), a bottom plate rock sample (2) being arranged on the bottom of the coal sample (3), a loading mechanism (5) being arranged on the top of the box body (1), a gas filling mechanism being arranged on one side of the box body (1), a monitoring mechanism being arranged in the box body (1), the monitoring mechanism and the loading mechanism (5) being electrically connected to a control mechanism respectively; and the friction force between the contact surfaces of the coal and rock layers being adjusted according to test requirements.

2. The coal and gas outburst test device for simulating different coal-rock interfaces 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 interfaces according to claim 1, characterized in that: The gas filling mechanism comprises a gas injection port provided on the box body (1), the gas injection port being in communication with a high-pressure gas cylinder (11) and a vacuum pump (13) respectively.

4. The coal and gas outburst test device for simulating different coal-rock interfaces 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 interfaces 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 the test device for simulating coal and gas outburst at different coal-rock interfaces according to any one of claims 1 to 5, characterized in that: The following steps are involved: S1: Take coal blocks and rocks on site and prepare coal samples (3), roof rock samples (4) and floor rock samples (2); S2: Processing the coal sample (3), roof rock sample (4) and bottom rock sample (2) in S1, grinding the contact surfaces of the prepared coal sample (3), roof rock sample (4) and bottom rock sample (2), then measuring the friction force of the coal-rock contact surface, and loading the processed coal sample (3), roof rock sample (4) and 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: Turn on the vacuum pump (13) to evacuate the box (1), and then inject gas into the coal layer to a predetermined pressure and fully adsorb it; 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 the interface between different coal and rock 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 treated by sandpaper or by adding industrial adhesive.

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