Dynamic load disturbance test system for triaxial loading of sample containing adsorbed gas

Abstract

The invention discloses a triaxial loading adsorption gas-containing sample dynamic load disturbance test system, and belongs to the field of safety science and engineering.The triaxial loading adsorption gas-containing sample dynamic load disturbance test system comprises an experiment table, a test cavity is formed in the upper surface of the experiment table, and a true triaxial confining pressure loading system is arranged in the test cavity; the inner wall of the right side of the test cavity is connected with an adsorption gas pressurization system through a first gas pipeline, a collision pressing plate is arranged on the inner wall of the left side of the test cavity in a penetrating mode, and a dynamic load disturbance system is arranged on the left side of the collision pressing plate. The true triaxial confining pressure loading system, the adsorption gas pressurization system and the dynamic load disturbance system are electrically connected with a data acquisition system. The triaxial loading dynamic load disturbance test system for the sample containing the adsorbed gas is reasonable in design, safe, reliable and easy to operate, and not only is beneficial to research on the problem of coal rock dynamic disasters, but also is beneficial to research on the mechanical property change and the fracture development law of the sample.

Description

Technical Field

[0001] The invention relates to the field of safety science and engineering, and in particular to a triaxial loading dynamic load disturbance test system for a sample containing adsorbed gas. Background Art

[0002] At present, coal resources are still the main energy source in my country. Due to the depletion of shallow coal resources, the depth of coal mining is gradually deepening, and my country's coal resources have entered the era of deep mining. With the increase in the depth of coal seam mining, the deep environment gradually becomes more complex, and the coal seams mainly show characteristics such as high ground stress, high gas pressure, high gas content, and low permeability. These factors not only affect the normal mining and supply of coal, but also cause coal-rock dynamic disasters such as rock burst, coal and gas outburst. In order to reduce the probability and frequency of coal-rock dynamic disasters, it is necessary to understand and master the occurrence mechanism and disaster-causing mechanism of coal-rock dynamic disasters, which is crucial for the reliable mining of coal seams and safe production of coal mines. The relevant research on coal-rock dynamic disasters was investigated and analyzed, and it was found that most scholars conducted research based on statics-related theories and experimental equipment, and their experimental equipment mainly included triaxial confining pressure loading system and data acquisition system. Since the existing test system has some functional defects and cannot fully meet the actual geological environment in which the specimens are located, it will cast doubts on the research results of coal-rock dynamic disasters, the credibility of the results will be low, and the control measures applied to the site will be ineffective. Moreover, it cannot fundamentally reveal the occurrence mechanism and disaster-causing mechanism of coal-rock dynamic disasters.

[0003] In view of the problems such as the inadequate functions of the existing test system, it is necessary to study a triaxial loading dynamic load disturbance test system for samples containing adsorbed gas. Based on the original equipment, the test system adds an adsorbed gas pressurizing device and a dynamic load disturbance device, which meets the stress condition and air pressure environment of the sample, highly simulates and restores the environment in which the sample is located, and studies the changes in the mechanical properties of the sample under different confining pressure and air pressure conditions; at the same time, it can also meet the dynamic load disturbance conditions of the sample, and study the changes in the mechanical properties of the sample caused by dynamic load disturbances of different intensities. Studying a triaxial loading dynamic load disturbance test system for samples containing adsorbed gas is not only conducive to studying the changes in the mechanical properties of coal bodies, but also conducive to revealing the occurrence mechanism and disaster-causing mechanism of coal-rock dynamic disasters. It will not only have important guiding significance for the research on the damage and destruction morphology of coal bodies, the law of crack development, gas adsorption and desorption, and outburst prevention and control, but also has important application value in the fields of safety science and engineering, mining engineering, etc. Summary of the invention

[0004] The purpose of the present invention is to provide a triaxially loaded dynamic load disturbance test system for samples containing adsorbed gas, which is used to study the changes in the mechanical properties of samples under different triaxial confining pressures, the changes in the mechanical properties of samples under different air pressure environments, the changes in the mechanical properties of samples under dynamic load disturbances of different intensities, etc., and further study the influence of the changes in the mechanical properties of the samples on their dynamic damage, failure morphology, and crack development, providing favorable guidance for safe production in coal mines.

[0005] To achieve the above-mentioned objectives, the present invention provides a triaxial loading dynamic load disturbance test system for samples containing adsorbed gas, comprising a test bench, a test cavity is provided on the upper surface of the test bench, a true triaxial confining pressure loading system is provided inside the test cavity, an adsorbed gas pressurization system is connected to the right inner wall of the test cavity through a first gas pipeline, a collision pressure plate is penetrated through the left inner wall of the test cavity, a dynamic load disturbance system is provided on the left side of the collision pressure plate, and the true triaxial confining pressure loading system, the adsorbed gas pressurization system and the dynamic load disturbance system are all electrically connected to a data acquisition system.

[0006] Preferably, one side of the test cavity is connected with an anti-collision bracket by fastening bolts, and the anti-collision bracket is fixed on the upper surface of the experimental table.

[0007] Preferably, the true triaxial confining pressure loading system includes a hydraulic oil pump and a pressure plate. The hydraulic oil pump is arranged on the outer surface of the test cavity, the pressure plate is arranged on the inner wall surface of the test cavity, and the pressure plate is connected to the telescopic end of the hydraulic oil pump.

[0008] Preferably, the adsorption gas pressurization system includes an adsorption gas cylinder, a first pressure regulating valve, a first pressure gauge, and a first switch. The adsorption gas cylinder is connected to the first gas pipeline through the first pressure regulating valve, the first pressure gauge, and the first switch in sequence. The gas pressure entering the test chamber is adjusted by controlling the first pressure regulating valve and the first switch.

[0009] Preferably, the dynamic load disturbance system includes a nitrogen cylinder, a second gas pipeline, a gas storage cylinder, a slider, an acceleration pipeline, and a fixed bracket. The nitrogen cylinder is connected to the gas storage cylinder through the second gas pipeline. The second gas pipeline is connected to a second pressure regulating valve, a second pressure gauge, and a second switch. The gas storage cylinder is connected to one end of the acceleration pipeline through a third gas pipeline. A solenoid valve is provided at the connection between the third gas pipeline and the gas storage cylinder. The slider is arranged inside the acceleration pipeline. The gas storage cylinder and the acceleration pipeline are both fixed to the upper surface of the experimental table through the fixed bracket. The outlet end of the acceleration pipeline corresponds to the force-bearing end of the collision pressure plate.

[0010] Preferably, the data acquisition system includes a data acquisition instrument, a laser speed sensor, an air pressure sensor, and a piezoelectric sensor. The laser speed sensor is arranged on the inner wall of the acceleration pipe outlet end, the air pressure sensor is arranged on the inner wall surface of the test chamber, and the piezoelectric sensor is arranged on the force-bearing end surface of the impact plate. The laser speed sensor, the air pressure sensor, and the piezoelectric sensor are all electrically connected to the data acquisition instrument.

[0011] Therefore, the present invention adopts the above-mentioned triaxial loading dynamic load disturbance test system for adsorbed gas sample, which has the following technical effects:

[0012] (1) The present invention includes a true triaxial confining pressure loading system, which can realize confining pressure graded loading and confining pressure synchronous loading, and is used to simulate the real stress environment of the sample, which has a guiding role in the study of the mechanical properties of triaxial confining pressure samples and is of great significance to the damage and destruction research of coal bodies;

[0013] (2) The present invention includes an adsorbed gas pressurization system, which injects adsorbed gas into the cavity to simulate the real air pressure environment of the sample, providing a strong basis for studying the effect of air pressure environment changes on the mechanical properties of the sample, and is of great significance for studying the law of fracture development in coal seams;

[0014] (3) The present invention includes a dynamic load disturbance system, which provides dynamic load disturbance energy to the slider to simulate the influence of dynamic load disturbances of different intensities on the changes in the mechanical properties of the triaxial confining pressure specimens, and provides parameter support for the study of dynamic damage of the specimens, which is of great significance to the safe excavation of coal tunnels.

[0015] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of a triaxial loading dynamic disturbance test system for a sample containing adsorbed gas according to the present invention;

[0017] Figure 2 The present invention is a schematic diagram of a slider structure of a triaxial loading dynamic disturbance test system for a sample containing adsorbed gas.

[0018] Reference numerals

[0019] 1. Experimental table; 2. Test chamber; 3. True triaxial confining pressure loading system; 31. Hydraulic oil pump; 32. Pressure plate; 4. First gas pipeline; 5. Adsorption gas pressurization system; 51. Adsorption gas cylinder; 52. First pressure regulating valve; 53. First pressure gauge; 54. First switch; 6. Impact pressure plate; 7. Dynamic load disturbance system; 71. Nitrogen cylinder; 72. Second gas pipeline; 73. Gas storage cylinder; 74. Slider; 75. Acceleration pipeline; 76. Fixed bracket; 77. Second pressure regulating valve; 78. Second pressure gauge; 79. Second switch; 8. Anti-collision bracket; 9. Data acquisition system; 91. Laser speed sensor; 92. Air pressure sensor; 93. Piezoelectric sensor; 94. Data acquisition instrument; 10. Solenoid valve; 11. Third gas pipeline. DETAILED DESCRIPTION

[0020] The technical solution of the present invention is further described below through the accompanying drawings and embodiments.

[0021] Unless otherwise defined, the technical terms or scientific terms used in the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0022] Embodiment 1

[0023] like Figure 1 As shown, a triaxial loading dynamic load disturbance test system for adsorbed gas sample mainly includes a test bench 1, a test chamber 2, a true triaxial confining pressure loading system 3, an adsorbed gas pressurization system 5, a dynamic load disturbance system 7 and a data acquisition system 9.

[0024] A test cavity 2 is fixedly provided on the upper surface of the test bench 1, and the inside of the test cavity 2 is used to place the sample to be tested. An anti-collision bracket 8 is connected to one side of the test cavity 2 by fastening bolts, and the anti-collision bracket 8 is fixedly provided on the upper surface of the test bench 1. The provision of the anti-collision bracket 8 can effectively prevent the impact and collision test from causing damage to the test cavity 2, and improve the stability and safety of the experimental system.

[0025] A true triaxial confining pressure loading system 3 is provided inside the test cavity 2, and the system includes a hydraulic oil pump 31 and a pressing plate 32. The hydraulic oil pump 31 is provided through the outer surface of the test cavity 2, and the pressing plate 32 is provided on the inner wall surface of the test cavity 2 and connected to the telescopic end of the hydraulic oil pump 31. By controlling the telescopic movement of the hydraulic oil pump 31, the pressing plate 32 can be pushed to perform confining pressure loading on the sample in three directions, simulating a real formation pressure environment.

[0026] The right inner wall of the test chamber 2 is connected to the adsorption gas pressurizing system 5 through the first gas pipeline 4. The adsorption gas pressurizing system 5 includes an adsorption gas cylinder 51, a first pressure regulating valve 52, a first pressure gauge 53 and a first switch 54. The adsorption gas cylinder 51 is connected to the first gas pipeline 4 through the first pressure regulating valve 52, the first pressure gauge 53 and the first switch 54 in sequence. By adjusting the opening degree of the first pressure regulating valve 52 and the first switch 54, the gas pressure entering the test chamber 2 can be accurately controlled.

[0027] A collision plate 6 is provided through the inner wall on the left side of the test chamber 2, and a dynamic load disturbance system 7 is provided on the left side of the collision plate 6. The dynamic load disturbance system 7 includes a nitrogen cylinder 71, a second gas pipeline 72, a gas storage cylinder 73, a slider 74, an acceleration pipeline 75, and a fixed bracket 76. The nitrogen cylinder 71 is connected to the gas storage cylinder 73 through the second gas pipeline 72, and the second gas pipeline 72 is provided with a second pressure regulating valve 77, a second pressure gauge 78, and a second switch 79. The gas in the nitrogen cylinder 71 enters the gas storage cylinder 73 through the second gas pipeline 72, and the gas in the gas storage cylinder 73 enters the acceleration pipeline 75 through the third gas pipeline 11 under the control of the solenoid valve 10, pushing the slider 74 to accelerate. When the slider 74 moves to the outlet end inside the acceleration pipeline 75, it hits the collision plate 6 to generate an impact force and transmits it to the sample inside the test chamber 2, thereby achieving the effect of dynamic load disturbance. Figure 2 As shown, different shapes of the slider 74 represent different impact waveforms generated after the collision.

[0028] The true triaxial confining pressure loading system 3, the adsorbed gas pressurization system 5 and the dynamic load disturbance system 7 are all electrically connected to the data acquisition system 9. The data acquisition system 9 includes a data acquisition instrument 94, a laser velocity sensor 91, an air pressure sensor 92 and a piezoelectric sensor 93. The laser velocity sensor 91 is arranged on the inner wall of the outlet end of the acceleration pipe 75 to measure the speed of the slider 74; the air pressure sensor 92 is arranged on the inner wall surface of the test cavity 2 to monitor the air pressure change inside the test cavity 2; the piezoelectric sensor 93 is arranged on the force end surface of the impact plate 6 to test the impact waveform of the impact plate 6. All these data are transmitted to the data acquisition instrument 94 in real time for analysis and processing.

[0029] Working principle:

[0030] 1. Activate the true triaxial confining pressure loading system 3: place the specimen into the test chamber 2, control the computer and set the minimum loading value of the hydraulic oil pump 31, and fix the specimen with the pressing plate 32.

[0031] 2. Enable the data acquisition system 9: The data acquisition instrument 94 is always connected to the sensor, and displays and records the relevant parameters monitored by the sensor.

[0032] 3. Activate the adsorbed gas pressurizing system 5: After the sample is fixed by the pressure plate 32, adjust the first pressure regulating valve 52, and after the reading of the first pressure gauge 53 reaches a preset value and stabilizes, open the first switch 54 to force the adsorbed gas to enter the cavity, and close the switch in time.

[0033] 4. Re-activate the true triaxial confining pressure loading system 3: After the adsorption gas pressurization is completed, control the computer and set the loading value of the hydraulic oil pump 31, and the pressure plate 32 loads the triaxial confining pressure on the sample.

[0034] 5. Enable the dynamic load disturbance system 7: After the triaxial confining pressure loading of the sample is completed, adjust the second pressure regulating valve 77, and after the reading of the second pressure gauge 78 reaches a preset value and stabilizes, open the second switch 79 to force nitrogen to enter the gas storage bottle 73, and close the second switch 79 in time, and then open the solenoid valve 10 to release the nitrogen in the gas storage bottle 73.

[0035] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A triaxial loading dynamic disturbance test system for a sample containing adsorbed gas, characterized in that: The test bench comprises a test chamber on the upper surface of which a true triaxial confining pressure loading system is arranged inside the test chamber; an adsorption gas pressurization system is connected to the right inner wall of the test chamber via a first gas pipeline; a collision plate is penetrated through the left inner wall of the test chamber; a dynamic load disturbance system is arranged on the left side of the collision plate; the true triaxial confining pressure loading system, the adsorption gas pressurization system and the dynamic load disturbance system are all electrically connected to a data acquisition system.

2. A triaxial loading dynamic disturbance test system for a sample containing adsorbed gas according to claim 1, characterized in that: One side of the test cavity is connected with an anti-collision bracket by fastening bolts, and the anti-collision bracket is fixed on the upper surface of the experimental table.

3. A triaxial loading dynamic disturbance test system for a sample containing adsorbed gas according to claim 1, characterized in that: The true triaxial confining pressure loading system includes a hydraulic oil pump and a pressure plate. The hydraulic oil pump is arranged on the outer surface of the test cavity, the pressure plate is arranged on the inner wall surface of the test cavity, and the pressure plate is connected to the telescopic end of the hydraulic oil pump.

4. A triaxial loading dynamic disturbance test system for a sample containing adsorbed gas according to claim 1, characterized in that: The adsorption gas pressurization system includes an adsorption gas cylinder, a first pressure regulating valve, a first pressure gauge, and a first switch. The adsorption gas cylinder is connected to the first gas pipeline through the first pressure regulating valve, the first pressure gauge, and the first switch in sequence. The gas pressure entering the test chamber is adjusted by controlling the first pressure regulating valve and the first switch.

5. A triaxial loading dynamic disturbance test system for a sample containing adsorbed gas according to claim 1, characterized in that: The dynamic load disturbance system includes a nitrogen cylinder, a second gas pipeline, a gas storage cylinder, a slider, an acceleration pipeline, and a fixed bracket. The nitrogen cylinder is connected to the gas storage cylinder through the second gas pipeline. The second gas pipeline is connected to a second pressure regulating valve, a second pressure gauge, and a second switch. The gas storage cylinder is connected to one end of the acceleration pipeline through a third gas pipeline. A solenoid valve is provided at the connection between the third gas pipeline and the gas storage cylinder. The slider is arranged inside the acceleration pipeline. The gas storage cylinder and the acceleration pipeline are both fixed on the upper surface of the experimental table through the fixed bracket. The outlet end of the acceleration pipeline corresponds to the force-bearing end of the collision pressure plate.

6. A triaxial loading dynamic disturbance test system for a sample containing adsorbed gas according to claim 5, characterized in that: The data acquisition system includes a data acquisition instrument, a laser speed sensor, an air pressure sensor, and a piezoelectric sensor. The laser speed sensor is arranged on the inner wall of the acceleration pipe outlet end, the air pressure sensor is arranged on the inner wall surface of the test chamber, and the piezoelectric sensor is arranged on the force-bearing end surface of the impact pressure plate. The laser speed sensor, the air pressure sensor, and the piezoelectric sensor are all electrically connected to the data acquisition instrument.

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