Triaxial loading coal rock gas expansion energy measuring device and method at impact disturbance moment

Abstract

The invention relates to the field of coal rock gas expansion energy testing, and particularly discloses a triaxial loading coal rock gas expansion energy measuring device and method at the moment of impact disturbance. The measuring device comprises a coal sample loading tank, a sealing sleeve, a top cover, a piston body, a piston tube, an elastic component, a disturbance impact rod, a first load applying piece, a second load applying piece, a temperature sensor and a pressure sensor. According to the measuring device and method, the accuracy and reliability of the simulation test result of the coal rock gas expansion energy can be effectively improved, so that the risk of gas accidents is reduced, and the mining safety of a coal mine is improved.

Description

Technical Field

[0001] The invention relates to the field of coal-rock gas expansion energy testing, and in particular to a device and method for measuring coal-rock gas expansion energy under triaxial loading at the moment of impact disturbance. Background Art

[0002] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention, and should not necessarily be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art.

[0003] Coal and gas outburst is a dynamic phenomenon in which a large amount of coal, rock and gas suddenly rush into the mining space under the combined action of ground stress and gas pressure. With the continuous increase in the intensity and depth of coal resource mining, coal and gas outburst accidents have gradually become the main disaster accidents that affect the continuous improvement of coal mine safety. The power and energy for the outburst mainly come from the energy converted from the sudden release of gas in the coal body cracks to the outside world within a few seconds. The amount of this energy determines the occurrence and development of the outburst. The initial gas expansion energy can characterize the size of this energy, and it has been widely used in coal mine gas disaster prevention, control, prediction and early warning. Therefore, the accurate test of the initial gas expansion energy of coal and rock has become an important issue in coal mine safety production.

[0004] However, in actual mines, the initial gas expansion energy of coal rock is jointly affected by factors such as dynamic disturbance, ground stress, gas pressure and the strength of the coal body itself. Especially for coal and gas outbursts induced by impact disturbance, the coal body is often in a complex stress state of "triaxial stress + impact disturbance". However, current testing technology is generally unable to simulate the expansion energy of coal rock gas under the above-mentioned complex stress state, resulting in the test results being difficult to truly reflect the actual situation, which in turn leads to insufficient accuracy in evaluating coal and gas outburst events that may occur during coal mining. Summary of the invention

[0005] In view of the above problems, the present invention proposes a device and method for measuring coal-rock gas expansion energy under impact disturbance instantaneous triaxial loading, which can effectively improve the accuracy and reliability of the simulation test results of coal-rock gas expansion energy, thereby reducing the risk of gas accidents and improving coal mine mining safety. Specifically, the technical solution of the present invention is as follows.

[0006] First, the present invention provides a device for measuring the expansion energy of coal and rock gas under instantaneous triaxial loading under impact disturbance, comprising: a coal sample loading tank, a sealing sleeve, a top cover, a piston body, a piston tube, an elastic component, a disturbance impact rod, a first load applying member, a second load applying member, a temperature sensor and a pressure sensor. Among them: the upper end of the coal sample loading tank is open, and a groove is provided on its inner side wall. The flexible sealing sleeve is vertically inserted into the inner cavity of the coal sample loading tank and the two are in sealed contact. A confining pressure cavity is formed between the outer side wall of the sealing sleeve and the groove, and both the confining pressure cavity and the bottom surface of the inner cavity of the coal sample loading tank have air holes. The top cover seals and covers the upper port of the coal sample loading tank. The top cover has a vertically arranged through-conical cavity. The piston body is located in the conical cavity, the lower end of the piston tube is fixedly connected to the piston body, and the upper end passes through the exhaust port. The elastic component is sleeved on the piston tube and is located between the top surface of the top cover and the upper end limiter of the piston tube. The piston body squeezes the side wall of the conical cavity under the action of the elastic component, thereby closing the exhaust port. The lower end of the disturbance impact rod passes through the piston tube and the piston body in sequence and is located in the conical cavity, and the disturbance impact rod and the piston tube are slidably and sealedly connected. The first load applying member is movably sleeved on the disturbance impact rod and supported on the limit member. The second load applying member located above the first load applying member is movably sleeved on the disturbance impact rod and supported on the disturbance impact rod. The temperature sensor is arranged in the conical cavity, and the pressure sensor is arranged in the conical cavity and the confining pressure cavity.

[0007] Furthermore, the upper and lower ports of the sealing sleeve each have a first sealing ring integrally connected to the sealing sleeve, which is sealed and connected to the inner cavity of the coal sample loading tank. Optionally, the sealing sleeve is made of a flexible material such as rubber or plastic.

[0008] Furthermore, the top cover is detachably connected to the upper port of the coal sample loading tank.

[0009] Further, a stopper is provided on the side wall of the disturbance impact rod, and the second load applying member is sleeved on the disturbance impact rod and supported on the stopper. Alternatively, the upper portion diameter of the disturbance impact rod is smaller than the lower portion diameter, so that a step located above the first load applying member is formed on the disturbance impact rod, and the second load applying member is sleeved on the disturbance impact rod and supported on the step.

[0010] Furthermore, a second sealing ring is sleeved on the side wall of the disturbance impact rod, and the disturbance impact rod is slidably and sealedly connected with the piston tube through the second sealing ring.

[0011] Furthermore, an impact plate is fixed to the lower end of the disturbance impact rod, and is located above the upper port of the coal sample loading tank to apply a more uniform impact load to the coal sample in the coal sample loading tank.

[0012] Furthermore, the gas hole includes: a first gas hole and a second gas hole. The first gas hole is arranged on the side wall of the confining pressure cavity, and is used to fill gas into the confining pressure cavity to form confining pressure. The second gas hole is arranged on the bottom surface of the inner cavity of the coal sample loading tank, and is used to extract gas or fill gas.

[0013] Furthermore, the pressure sensor comprises: a first pressure sensor and a second pressure sensor. The first pressure sensor is arranged in the confining pressure chamber to monitor the magnitude of the confining pressure. The second pressure sensor is arranged in the conical cavity to monitor the pressure therein.

[0014] Secondly, the present invention provides a method for measuring the expansion energy of coal, rock and gas under triaxial loading at the moment of impact disturbance, comprising the following steps: (1) Insert the coal sample to be tested into the sealing sleeve so that the side walls of the two are in close contact. Then cover the top cover and fix it to the coal sample loading tank. At this time, the lower end of the disturbance impact rod is supported on the top surface of the coal sample to be tested.

[0015] (2) Evacuate the air holes on the bottom surface of the inner cavity of the coal sample loading tank. After completion, fill gas from the air holes of the confining pressure chamber to form pressure on the side wall of the sealing sleeve. The pressure is the same as the confining pressure of the natural coal seam where the coal sample specimen to be tested is located. After completion, close the air holes of the confining pressure chamber. Then, apply a static axial pressure to the upper end surface of the coal sample specimen to be tested through the top end of the disturbance impact rod. The static axial pressure is the same as the axial pressure of the natural coal seam where the coal sample specimen to be tested is located. After completion, fill gas into the conical cavity until the gas pressure therein is the same as the gas pressure of the natural coal seam where the coal sample specimen to be tested is located. Then let it stand until the coal sample specimen to be tested absorbs the gas to reach an equilibrium state, and during this process, keep the temperature the same as the temperature of the natural coal seam. After completion, record the gas pressure in the confining pressure chamber. q 1 , the air pressure in the conical cavity q 2 and its temperature T .

[0016] (3) The first load applying member and the second load applying member are raised to a set height and then released, wherein the first load applying member impacts the top of the piston tube, thereby driving the piston body to descend so that the exhaust port of the conical cavity is opened. At the same time, during the above process, the second load applying member impacts the top of the disturbance impact rod, thereby driving the lower end of the disturbance impact rod to apply an impact load to the coal sample to be tested for disturbance. The gas in the conical cavity is ejected at the moment the exhaust port is opened, and then the gas flow rate ejected from the exhaust port is calculated based on the collected temperature and pressure of the conical cavity. Q and flow rate vThen, the kinetic energy data of the ejected gas is calculated based on the data, and then the gas expansion energy curve a of the coal sample to be tested at the moment of disturbance is calculated based on the kinetic energy data.

[0017] (4) Replace the coal sample to be tested with a rigid specimen without gas absorption properties, and repeat the above steps (1) to (3) to obtain the gas expansion energy curve b of the rigid specimen. Then, the gas expansion energies of the gas outburst stage of the curves a and b are integrated and subtracted, and the result of the subtraction is divided by the mass of the coal sample to be tested to obtain the coal rock gas expansion energy.

[0018] Compared with the prior art, the present invention has at least the following beneficial technical effects: The device for measuring the expansion energy of coal and rock gas under triaxial loading at the moment of impact disturbance of the present invention is a special mechanism composed of the top cover, piston body, piston tube, elastic component, disturbance impact rod, first load applying member, second load applying member, and the confining pressure chamber formed by the sealing sleeve and the coal sample loading tank, which ensures that the coal sample is in the same stress environment as the natural coal seam when the test is carried out, and the adsorbed gas in the coal sample loading tank is released instantly while the disturbance is being carried out, so that the measured data is the gas expansion energy formed at the moment of triaxial loading coal sample disturbance, which effectively improves the accuracy and reliability of the simulation test results of coal and rock gas expansion energy, helps to reduce the accurate assessment of the risk of gas accidents, and improves the safety of coal mining. At the same time, the present invention also proposes a measurement method based on the above-mentioned device, which further provides a new solution for the accurate simulation test of coal and rock gas expansion energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0020] Figure 1 Schematic diagram of the structure of the coal-rock gas expansion energy measuring device in the following embodiments.

[0021] Figure 2 2 is a cross-sectional view of a device for measuring coal rock gas expansion energy in the following embodiments.

[0022] Figure 3 Schematic diagram of the structure of the piston body in the following embodiments.

[0023] Figure 4 Schematic diagram of the internal structure of the top cover in the following embodiments.

[0024] Figure 5 Schematic diagram of the structure of the disturbance impact rod in the following embodiments.

[0025] Figure 6 The gas pressure variation curve of the coal sample specimen in the following examples is shown in FIG.

[0026] Figure 7 The following is a graph showing the kinetic energy of the gas ejected from the coal sample specimens in the following embodiments.

[0027] Figure 8 The following is a graph showing the change in gas pressure of the iron block specimen in the following examples.

[0028] Fig. 9 The following is a graph showing the kinetic energy of the gas ejected from the iron block specimen in the following example.

[0029] Fig.10 Graph showing gas expansion energy in the following embodiments.

[0030] Above Figure 1-5 The marks in the figure represent respectively: 1-coal sample loading tank, 2-sealing sleeve, 3-top cover, 4-piston body, 5-piston tube, 6-elastic component, 7-disturbance impact rod, 8-first load applying member, 9-second load applying member, 10-temperature sensor, 101-confining pressure chamber, 102-first air hole, 103-second air hole, 104-first pressure sensor, 201-first sealing ring, 301-conical cavity, 302-exhaust port, 303-second pressure sensor, 501-limiting member, 701-second sealing ring, 702-impact disk. DETAILED DESCRIPTION

[0031] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0032] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should also be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0033] For the convenience of description, if the words "up", "down", "left" and "right" appear in the present invention, they only indicate that they are consistent with the up, down, left and right directions of the drawings themselves, and do not limit the structure. They are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred device or component needs to have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present invention.

[0034] The device and method for measuring the expansion energy of coal, rock and gas under instantaneous triaxial loading under impact disturbance of the present invention will now be further described in conjunction with the accompanying drawings and specific embodiments of the specification.

[0035] refer to Figure 1 , Figure 2 , Figure 3 and Figure 4 , an impact disturbance instantaneous triaxial loading coal-rock gas expansion energy measuring device is exemplified, comprising: a coal sample loading tank 1, a sealing sleeve 2, a top cover 3, a piston body 4, a piston tube 5, an elastic component 6, a disturbance impact rod 7, a first load applying member 8, a second load applying member 9, and a temperature sensor 10. Specifically: the coal sample loading tank 1 is vertically arranged, and its upper end is open. A circle of grooves is provided on the side wall of the inner cavity of the coal sample loading tank 1. The sealing sleeve 2 is a cylinder made of a flexible material such as rubber and plastic, and both the upper and lower ports are open. The sealing sleeve 2 is vertically inserted into the inner cavity of the coal sample loading tank 1, and the upper and lower ports of the sealing sleeve 2 are provided with a first sealing ring 201 integrally connected to the sealing sleeve 2. Among them, the first sealing ring 201 at the upper end of the sealing sleeve 2 is pressed by the upper end face of the coal sample loading tank 1 and the bottom face of the top cover 3 to play a sealing role between the two, and the first sealing ring 201 at the lower end of the sealing sleeve 2 is pressed by the bottom cover between it and the lower end face of the coal sample loading tank 1, thereby forming a sealed connection between the sealing sleeve 2 and the coal sample loading tank 1 to prevent leakage of the following confining pressure chamber 101.

[0036] A confining pressure chamber 101 is formed between the outer wall of the sealing sleeve 2 and the groove, and a first air hole 102 is provided on the side wall of the coal sample loading tank 1, and the first air hole 102 is connected to the confining pressure chamber 101. In order to fill the confining pressure chamber 101 with gas, the pressure formed can be evenly applied to the side wall of the sealing sleeve 2 to form a confining pressure. Since the sealing sleeve 2 is a flexible structure, it can further transmit the confining pressure to the coal sample specimen to be tested loaded in the sealing sleeve 2, so that the test is closer to the real environment of the coal rock. A second air hole 103 is provided on the bottom surface of the inner cavity of the coal sample loading tank 1, which is used for vacuuming, or filling gas after vacuuming. The filled gas gradually passes through the coal sample specimen to be tested and enters the conical cavity 301.

[0037] The lower port of the conical cavity 301 is located on the bottom surface of the top cover 3. During testing, the top cover 3 covers the upper port of the coal sample loading tank 1 and the two are detachably connected by bolts and other fasteners, and at this time, the conical cavity 301 is butted with the upper port of the sealing sleeve 2 in the coal sample loading tank 1. The upper end of the conical cavity 301 is an exhaust port 302, and the port of the exhaust port 302 is located on the top surface of the top cover 3, so that the high-pressure gas in the conical cavity 301 can be discharged during testing.

[0038] The piston body 4 is arranged in the conical cavity 301, and the piston body 4 is a conical body matching the conical cavity 301. The piston tube 5 is arranged vertically, and its lower end is fixedly connected to the center of the upper surface of the piston body 4. The upper end of the piston tube 5 is located above the exhaust port 302 after passing through it, and the upper end of the piston tube 5 has a limiter 501 fixed on its side wall. The elastic component 6 can be a spring, which is sleeved on the piston tube 5, and the lower end of the elastic component 6 is supported on the top surface of the top cover 3, and the upper end abuts on the lower surface of the limiter 501. Under the upward force applied by the elastic component 6 to the piston tube 5, the side wall of the piston body 4 is squeezed on the side wall of the conical cavity 301, thereby forming a closure for the exhaust port 302. The piston body 4 can be made of elastic materials such as rubber.

[0039] The disturbance impact rod 7 is arranged vertically, and its lower end passes through the piston tube 5 and the piston body 4 in sequence and is located in the conical cavity 301. There are several annular grooves distributed along the height direction on the side wall of the disturbance impact rod 7, in which a second sealing ring 701 is sleeved. The second sealing ring 701 is squeezed on the inner wall of the piston body 4 at the same time, so as to realize the sliding and sealing connection between the disturbance impact rod 7 and the piston tube 5, which not only ensures that the disturbance impact rod 7 can move vertically, but also avoids leakage from the gap between the disturbance impact rod 7 and the piston tube 5 when inflating through the second air hole 103, resulting in inaccurate measurement results. In addition, when the exhaust port 302 is opened for exhaust later, the gas in the conical cavity 301 can only be ejected and released from the exhaust port 302, ensuring that the flow rate and velocity data of the ejected gas are accurate.

[0040] The first load applying member 8 is movably mounted on the disturbance impact rod 7 and supported on the stopper 501, so that the first load applying member 8 is lifted to a set height and then released to impact the top of the piston tube 5, thereby driving the piston tube 5 and the piston body 4 to descend synchronously, and the exhaust port 302 is instantly opened for exhaust. Figure 2 and Figure 5As shown, in this embodiment, the diameter of the upper part of the disturbance impact rod 7 is smaller than the diameter of the lower part, so that a step located above the first load applying member 8 is formed on the disturbance impact rod 7, and the second load applying member 9 is sleeved on the disturbance impact rod and supported on the step, so that the second load applying member 9 is located above the first load applying member 8. Therefore, the second load applying member 9 can be lifted to a set height according to the scale set on the disturbance impact rod 7 and then released to impact the disturbance impact rod 7, thereby driving the disturbance impact rod 7 to descend and applying an impact load to the coal sample to be tested set in the sealing sleeve 2 to disturb it. At the same time of the disturbance, the exhaust port 302 is instantly opened. Since the pressure in the conical cavity 301 is greater than the atmospheric pressure, the adsorbed gas in the coal sample to be tested will be desorbed, expand outward to do work, and be converted into kinetic energy, and then discharged outward from the exhaust port 302. Then, the flow rate of the gas ejected from the exhaust port 302 is calculated according to the temperature and pressure in the conical cavity 301 collected by the second pressure sensor 303 and the temperature sensor 10 described below. Q and flow rate v Then, the kinetic energy data of the gas ejected is calculated based on the data, and then the gas expansion energy of the coal sample to be tested at the moment of disturbance is calculated based on the kinetic energy data. The first load applying member 8 and the second load applying member 9 can be made of metal blocks such as steel and copper to ensure sufficient impact force when falling.

[0041] The temperature sensor 10 is arranged in the conical cavity 301 to monitor the temperature of the gas therein. The confining pressure cavity 101 is provided with a first pressure sensor 104 to monitor the size of the confining pressure formed by the gas filled into the confining pressure cavity 101. The conical cavity 301 is provided with a second pressure sensor 303 to monitor the pressure of the gas therein so as to calculate the gas expansion energy. In this embodiment, a special mechanism is formed by the top cover 3, the piston body 4, the piston tube 5, the elastic component 6, the disturbance impact rod 7, the first load applying member 8, the second load applying member 9, and the confining pressure cavity 101 formed by the sealing sleeve 2 and the coal sample loading tank 1, so that when the coal sample to be tested is disturbed, the gas in the conical cavity 301 is released instantly under the confining pressure state, ensuring that the measured data is the gas expansion energy of the coal sample at the moment of disturbance, so as to ensure the accuracy of the simulation test results, provide a more reliable basis for reducing the occurrence of gas accidents, and improve coal mining safety.

[0042] In another embodiment, a limit piece may be provided on the side wall of the disturbance impact rod 7, and the second load applying member 2 may be sleeved on the disturbance impact rod 7 and supported on the limit piece so that the disturbance impact rod 7 may be impacted after the second load applying member 9 is lifted to a set height and released.

[0043] In another embodiment, reference Figure 5 The lower end of the disturbance impact rod 7 of the measuring device in the above embodiment example is also fixed with a horizontally arranged impact disk 702, which is located in the conical cavity 301 above the upper port of the coal sample loading tank 1, so as to more evenly apply the impact force to the coal sample specimen to be tested in the sealing sleeve 2.

[0044] In another embodiment, the above-mentioned coal-rock gas expansion energy measuring device under instantaneous triaxial loading of impact disturbance is used as an execution device to provide a method for measuring coal-rock gas expansion energy, comprising the following steps: (1) Insert the coal sample to be tested (a cylinder with a diameter of 50 mm and a height of 100 mm) into the sealing sleeve 2 and make the side walls of the two closely contact, so that the sealing sleeve 2 tightly wraps the coal sample to be tested so as to apply confining pressure. Then cover the top cover 3 and fix it to the upper port of the coal sample loading tank 1 and seal it. At this time, the lower end of the disturbance impact rod 7 is supported on the top surface of the coal sample to be tested.

[0045] (2) Connect the second air hole 103 to the vacuum pump through a pipeline, open the valve on the pipeline, and then remove the free gas and residual air in the coal sample for half an hour, so as to focus on the desorption behavior of the adsorbed gas in the coal sample and ensure the accuracy and reliability of the experimental results. Then stop pumping and close the valve on the vacuum pipeline. Then open the valve on the first air hole 102 of the confining pressure chamber 101 and connect it to the air compressor, and fill it with air until the first pressure sensor 104 detects that the air pressure in the confining pressure chamber 101 is the same as the confining pressure of the natural coal seam where the coal sample to be tested is located. After completion, close the valve on the first air hole 102 and stop filling. Then, apply a static load axial pressure (5.17MPa) to the upper end surface of the coal sample to be tested through the top of the disturbance impact rod 7, and its magnitude is the same as the axial pressure of the natural coal seam where the coal sample to be tested is located. Then connect the pipeline of the second air hole 103 to the charging device, open the valve on the pipeline and fill it with gas until the gas pressure in the conical cavity 301 is detected to be the same as the gas pressure of the natural coal seam where the coal sample to be tested is located (1.09MPa). Then let it stand for 8 hours, and the coal sample to be tested absorbs gas to reach an equilibrium state. During this process, the temperature is kept the same as the temperature of the natural coal seam (30.2℃). After completion, close the valve on the pipeline. Then record the gas pressure in the confining pressure cavity 101 obtained by the first pressure sensor 104 q 1. The air pressure in the conical cavity 301 obtained by the second pressure sensor 303 q 2. The temperature in the conical cavity 301 obtained by the temperature sensor 10 T .

[0046] (3) Then, the first load applying member 8 and the second load applying member 9 are raised to a set height and then released, wherein the first load applying member 8 impacts the top end of the piston tube 5, thereby driving the piston body 4 to descend so that the exhaust port 302 of the conical cavity 301 is opened. At the same time, during the above process, the second load applying member 9 impacts the top end of the disturbance impact rod 7, thereby driving the lower end of the disturbance impact rod 7 to apply an impact load to the coal sample to be tested for disturbance. At the moment the exhaust port 302 is opened, the gas in the conical cavity 301 is ejected from the exhaust port 302. Then, according to the gas pressure data in the conical cavity 301 collected by the second pressure sensor 303 (the result is as shown in FIG. 2 ), the gas pressure data in the conical cavity 301 is ejected from the exhaust port 302. Figure 6 As shown) and the temperature sensor 10 collect the temperature data in the conical cavity 301 to calculate the flow rate of the airflow ejected from the exhaust port 302 Q and speed v , and then according to the flow Q and speed v Calculate the kinetic energy data of the ejected gas (such as Figure 7 The calculation method refers to the existing literature 1: Analysis of the influence law and temperature effect of initial release of gas expansion energy of coal particles [J], Wang Hanpeng, Zhang Yuqiang, Yuan Liang, etc., Journal of Mining and Safety Engineering, Issue 05, 2019.

[0047] (4) Then according to Figure 7 The kinetic energy data shown are used to calculate the gas expansion energy of the coal sample to be tested at the moment of disturbance (the calculation method refers to the above-mentioned existing document 1), and the obtained gas expansion energy curve a is plotted.

[0048] (5) Replace the coal sample to be tested with a rigid body sample (iron block) of the same size, repeat the above steps (1) to (3), and calculate the gas pressure data collected in the conical cavity 301 (the result is as follows: Figure 8 As shown) and the temperature sensor 10 collect the temperature data in the conical cavity 301 to calculate the flow rate of the airflow ejected from the exhaust port 302 Q and speed v , and then according to the flow Q and speed v Calculate the kinetic energy data of the gas ejected from the exhaust port 302 (eg Fig. 9 Then according to Fig. 9 The kinetic energy data of the gas expansion energy curve b of the iron block specimen at the moment of disturbance is calculated. Since the iron block will not absorb the gas filled in, the flow rate of the gas gushing out of the dead space in the coal sample loading tank 1 and the conical cavity 301 can be measured after the coal sample to be tested is replaced with the iron block. Q and speed v .

[0049] (6) Integrate the gas expansion energies of the gas expansion energy curve a and the gas expansion energy curve b in the gas outburst stage and then subtract them (the gas expansion energies obtained after integration are as follows: Fig.10 As shown), and then dividing the result after subtraction by the mass of the coal sample specimen to be tested, the disturbed gas expansion energy per unit mass of the coal sample, that is, the coal rock gas expansion energy, can be obtained, and the result is 130mJ / g.

[0050] Finally, it should be noted that any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention. Although the above describes the specific implementation of the present invention in conjunction with the drawings, it is not a limitation of the protection scope of the present invention. Those skilled in the art should understand that on the basis of the technical solution of the present invention, various modifications or deformations that can be made by those skilled in the art without creative labor are still within the protection scope of the present invention.

Claims

1. A device for measuring coal-rock gas expansion energy under instantaneous triaxial loading under impact disturbance, characterized in that: include: A coal sample loading tank, the upper end of which is open and has a groove on its inner wall; A sealing sleeve, wherein the flexible sealing sleeve is vertically inserted into the inner cavity of the coal sample loading tank and the two are in sealed contact; a confining pressure cavity is formed between the outer wall of the sealing sleeve and the groove, and both the confining pressure cavity and the inner cavity bottom surface of the coal sample loading tank have air holes; A top cover, the top cover is sealed and covered on the upper port of the coal sample loading tank, and the top cover has a vertically arranged penetrating conical cavity, in which a piston body is arranged; A piston tube, the lower end of which is fixedly connected to the piston body and the upper end of which passes through the exhaust port; An elastic component, which is sleeved on the piston tube and is located between the top surface of the top cover and the upper end stopper of the piston tube, and the piston body squeezes the side wall of the conical cavity under the action of the elastic component, thereby sealing the exhaust port; A disturbance impact rod, the lower end of which passes through the piston tube and the piston body in sequence and is located in the conical cavity, and the disturbance impact rod is slidably and sealedly connected to the piston tube; A first load applying member, the first load applying member is movably sleeved on the disturbance impact rod and supported on the limiting member; A second load applying member, the second load applying member located above the first load applying member is movably sleeved on the disturbance impact rod and supported on the disturbance impact rod; A temperature sensor is arranged in the conical cavity, and pressure sensors are arranged in both the conical cavity and the confining pressure cavity.

2. The device for measuring coal-rock gas expansion energy under instantaneous triaxial loading under impact disturbance according to claim 1 is characterized in that: The upper and lower ports of the sealing sleeve are provided with a first sealing ring integrally connected with the sealing sleeve, which is sealed and connected with the inner cavity of the coal sample loading tank; or, the material of the sealing sleeve includes any one of rubber and plastic.

3. The device for measuring coal-rock gas expansion energy under instantaneous triaxial loading under impact disturbance according to claim 1 is characterized in that: The top cover is detachably connected to the upper port of the coal sample loading tank.

4. The device for measuring coal-rock gas expansion energy under instantaneous triaxial loading under impact disturbance according to claim 1 is characterized in that: A second sealing ring is sleeved on the side wall of the disturbance impact rod, and the disturbance impact rod is slidably and sealedly connected with the piston tube through the second sealing ring.

5. The device for measuring coal-rock gas expansion energy under instantaneous triaxial loading under impact disturbance according to claim 1 is characterized in that: An impact plate is fixed to the lower end of the disturbance impact rod and is located above the upper port of the coal sample loading tank.

6. The device for measuring coal-rock gas expansion energy under instantaneous triaxial loading under impact disturbance according to claim 1 is characterized in that: The disturbance impact rod has a side wall with a limit piece, and the second load applying piece is sleeved on the disturbance impact rod and supported on the limit piece; or, the upper portion of the disturbance impact rod has a smaller diameter than the lower portion, thereby forming a step on the disturbance impact rod above the first load applying piece, and the second load applying piece is sleeved on the disturbance impact rod and supported on the step.

7. The device for measuring coal-rock gas expansion energy under instantaneous triaxial loading under impact disturbance according to any one of claims 1 to 6, characterized in that: The air holes include: a first air hole and a second air hole; wherein: the first air hole is arranged on the side wall of the confining pressure cavity; the second air hole is arranged on the bottom surface of the inner cavity of the coal sample loading tank.

8. The device for measuring coal-rock gas expansion energy under instantaneous triaxial loading under impact disturbance according to any one of claims 1 to 6, characterized in that: The pressure sensor comprises: a first pressure sensor and a second pressure sensor; wherein: the first pressure sensor is arranged in the confining pressure cavity; and the second pressure sensor is arranged in the conical cavity.

9. A method for determining the expansion energy of coal, rock and gas under triaxial loading at the moment of impact disturbance, characterized in that: The measuring device for measuring coal-rock gas expansion energy under instantaneous triaxial loading under impact disturbance as described in any one of claims 1 to 8 is used as an actuator, and the measuring method comprises the following steps: (1) inserting the coal sample to be tested into the sealing sleeve so that the side walls of the two are in close contact; then covering the top cover and fixing it to the coal sample loading tank, at which time the lower end of the disturbance impact rod is supported on the top surface of the coal sample to be tested; (2) Vacuuming is performed from the air holes on the bottom surface of the inner cavity of the coal sample loading tank. After completion, gas is filled into the air holes of the confining pressure chamber to form pressure on the side wall of the sealing sleeve. The pressure is the same as the confining pressure of the natural coal seam where the coal sample specimen to be tested is located. After completion, the air holes of the confining pressure chamber are closed; then, a static load axial pressure is applied to the upper end surface of the coal sample specimen to be tested through the top end of the disturbance impact rod. The static load axial pressure is the same as the axial pressure of the natural coal seam where the coal sample specimen to be tested is located; after completion, gas is filled into the conical cavity until the gas pressure therein is the same as the gas pressure of the natural coal seam where the coal sample specimen to be tested is located; then, the confining pressure chamber is left to stand until the coal sample specimen to be tested absorbs gas and reaches an equilibrium state, and during this process, the temperature is kept the same as the temperature of the natural coal seam. After completion, the gas pressure in the confining pressure chamber is recorded. q 1 , the air pressure in the conical cavity q 2 and its temperature T ; (3) The first load applying member and the second load applying member are raised to a set height and then released, wherein the first load applying member impacts the top end of the piston tube, thereby driving the piston body to descend so that the exhaust port of the conical cavity is opened; at the same time, during the above process, the second load applying member impacts the top end of the disturbance impact rod, thereby driving the lower end of the disturbance impact rod to apply an impact load to the coal sample to be tested to disturb it; the gas in the conical cavity is ejected at the moment the exhaust port is opened, and then the gas flow rate ejected from the exhaust port is calculated based on the collected temperature and pressure of the conical cavity Q and flow rate v ; Then, the kinetic energy data of the ejected gas is calculated based on the data, and then the gas expansion energy curve a of the coal sample to be tested at the moment of disturbance is calculated based on the kinetic energy data; (4) The coal sample to be tested is replaced with a rigid specimen without gas absorption properties, and the above steps (1) to (3) are repeated to obtain the gas expansion energy curve b of the rigid specimen; then, the gas expansion energies of the curves a and b in the gas outburst stage are respectively integrated and subtracted, and the result of the subtraction is divided by the mass of the coal sample to be tested to obtain the coal rock gas expansion energy.

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