CN211740920U - Deep high stress and high permeability environment simulation experiment system - Google Patents

Abstract

The utility model discloses a deep high-stress and high-permeability environment simulation experimental system and an experimental method thereof. The experimental system comprises a confining pressure system, a rock sample clamping mechanism, an axial pressure system, an osmotic pressure system, and a rock sample volume change testing system. Harmony sound speed real-time test system; the confining pressure system, the axial pressure system and the osmotic pressure system are all equipped with a voltage stabilization mechanism, most of the rock sample holding mechanisms are installed in the confining pressure cylinder of the confining pressure system, and a small part is located in the axial pressure system The osmotic pressure system is divided into two parts, which are provided at the upper and lower ends of the rock sample. This scheme uses a voltage stabilization mechanism for load application, which can overcome the load fluctuation problem during long-term testing and make the test results more accurate. Axial rheological test method, which can restore the deep occurrence characteristics, so as to reveal the long-term mechanical behavior and permeability characteristics of deep rock mass more realistically.

Description

Deep high stress and high permeability environment simulation experiment system

technical field

The utility model relates to the technical field of geotechnical engineering, in particular to a deep high stress and high permeability environment simulation experiment system.

Background technique

In order to meet the needs of human survival and development and explore the unknown mysteries inside the earth, the development and utilization of deep space resources has become the future trend of human activities and the main way for human sustainable development. At the same time, the rapid development of the world economy needs to consume a huge amount of resources, which makes the shallow resources of the earth gradually depleted, and the exploitation of oil and gas, geothermal, coal mines, metal mines and other resources continues to move to the deep part of the earth, and deep resource exploitation will become the norm in the future. Therefore, marching into the depths of the earth has become a strategic scientific and technological problem that must be solved in the future development of mankind. However, the practice of deep rock mass engineering is often faced with complex environmental conditions of high stress and high osmotic pressure. Under the action of high pressure water, the probability of water softening of the rock mass continues to increase, resulting in significant changes in the properties of the rock mass, making the rock mass The micro-structure and macro-mechanical properties have changed significantly, which makes it difficult to accurately describe the long-term mechanical behavior and permeability characteristics of the rock mass, which seriously affects the long-term safe and stable operation of the surrounding rock in the deep cavern.

At present, there is little research on the long-term mechanical behavior and permeability characteristics of deep rock mass under the action of high stress and high osmotic pressure, and the accumulated knowledge and experience are very little. An important reason is that the existing experimental equipment is difficult to truly restore the deep original Bit assignment feature. In addition, the long-term stable control of high stress and high osmotic pressure is also a key and difficult problem. The existing MTS three-axis test machine mainly relies on electric power to drive the pressure pump, and injects oil into the cylinder to dynamically adjust the pressure and control the loading force in real time. In the long-term test process, the laboratory is prone to voltage instability during the peak period of power consumption, which affects the power of the pressure pump and thus the amount of oil injected into it, resulting in the confining pressure cylinder, axial pressure cylinder and oil in the osmotic pressure channel. The hydraulic pressure fluctuates, that is, the confining pressure, axial pressure and osmotic pressure cannot be kept stable, resulting in inaccurate experimental results.

Utility model content

In view of the above deficiencies in the prior art, the deep high stress and high permeability environment simulation experiment system and its experimental method provided by the present invention can stably simulate the in-situ experiment of the deep high stress and high permeability environment for a long time.

In order to achieve the above-mentioned purpose of the invention, the technical scheme adopted by the present utility model is:

Provided is a deep high-stress and high-permeability environment simulation experiment system, which includes:

The confining pressure system includes a confining pressure cylinder whose lower end is an open end, and the top of the confining pressure cylinder is sealed and connected with two confining pressure pipelines that communicate with it. A confining pressure gauge and a control valve are installed on the confining pressure pipeline; a voltage stabilizing mechanism is installed at the end of the other confining pressure pipeline;

The rock sample clamping mechanism includes a lower clamping seat and an upper clamping seat fixed on the top of the hydraulic cylinder, the upper end diameter of the lower clamping seat is larger than the lower end diameter; the upper clamping seat and the lower clamping seat are axially opened There is a water inlet hole therethrough;

The axial compression system includes an axial compression cylinder, and the top of the axial compression cylinder is sealed and connected with two axial compression pipelines that communicate with it. An axial pressure gauge and a control valve are installed; a voltage stabilizing mechanism is installed at the end of the other axial pressure pipeline;

The osmotic pressure system includes osmotic pressure pipes that penetrate into the confining pressure cylinder and the axial pressure cylinder respectively and are sealed with the corresponding water inlet holes. The osmotic pressure gauge and control valve are installed on the pipeline; the other end of the two osmotic pressure pipelines is equipped with a voltage stabilizing mechanism;

The top of the axial pressure cylinder is provided with an installation hole for the lower end of the lower clamping seat to enter, the lower end of the lower clamping seat is movable and sealed in the installation hole, the confining pressure cylinder is installed at the top of the axial pressure cylinder, and the two are sealed and connected; all The pump, control valve and pressure gauge are all connected to the processor.

The beneficial effects of the utility model are as follows: in this scheme, a voltage stabilizing mechanism is used to apply the load, and when the pressure of the three types of pressure gauges reaches the applied load, the control valve and the corresponding pump can be closed, so that during the long-term test, the It is necessary to start the electrical equipment all the time, so even if the external voltage fluctuates, it will not affect the normal operation of the system experiment. This system makes the test results more accurate by overcoming the load fluctuation problem in the long-term test process;

The osmotic pressure application is divided into upper and lower parts, and the pressure difference applied by the upper and lower parts is used as the osmotic pressure, so that not only the forward osmosis experiment but also the reverse osmosis experiment can be carried out. In addition, the osmotic pressure on the rock sample can be made more uniform and comprehensive.

Compared with the existing MTS three-axis experimental machine, the experimental system provided by this scheme has the advantages of simple structure, low cost, and easy miniaturization.

After the sound velocity real-time test system is added to this scheme, it can reflect the damage and deterioration of rock samples at the first time, and provide strong support for subsequent analysis; the system of this scheme is simulating high stress and high osmotic pressure (ie high confining pressure and high osmotic pressure) In the environment, the axial compression system is only used to provide upward force to the lower clamping seat to tighten the rock sample, and does not provide axial pressure. Through the simulation of this environment, the deterioration mechanism of the rock sample in this environment can be studied.

Description of drawings

Figure 1 is a schematic diagram of the structure of the deep high-stress and high-permeability environment simulation experiment system.

Figure 2 is a schematic diagram of a rock sample placed in a confining pressure cylinder and a volume change test system and a sound velocity real-time test system installed on the rock sample.

FIG. 3 is a schematic structural diagram of the sealing installation of the axial pressure cylinder and the confining pressure cylinder.

Figure 4 shows the change curve of the sound velocity of the rock creep test at a depth of 100m.

Fig. 5 shows the whole creep process curve of the rock sample at a depth of 100m.

Among them, 1, confining pressure system; 11, confining pressure cylinder; 12, confining pressure pipeline; 13, confining pressure pump; 14, confining pressure oil tank; 15, confining pressure pressure gauge; 16, control valve; 171, pressure rod; 172, piston; 173, base; 174, force application part; 2, rock sample clamping mechanism; 21, upper clamping seat; 211, water inlet; 22, lower clamping seat; 3, Axial compression system;

31. Axial pressure cylinder; 311. Mounting hole; 32. Axial pressure pipeline; 33. Axial pressure pump; 34. Axial pressure oil tank; 35. Axial pressure pressure gauge; 4. Osmotic pressure system; 41. Osmotic pressure pipeline; 42, osmotic pump; 43. osmotic water tank; 44. osmotic pressure gauge; 5. rock sample volume change test system; 51. circumferential displacement sensor; 52. axial displacement sensor; 61. ultrasonic signal transmitter; 62. Ultrasonic signal receiver.

Detailed ways

The specific embodiments of the present invention are described below to facilitate those skilled in the art to understand the present invention, but it should be clear that the present invention is not limited to the scope of the specific embodiments. Various changes are within the spirit and scope of the present utility model defined and determined by the appended claims, and these changes are obvious, and all utility model creations utilizing the concept of the present utility model are included in the protection list.

As shown in Figure 1, the deep high-stress and high-permeability environment simulation experiment system includes a confining pressure system 1, a rock sample clamping mechanism 2, an axial compression system 3, an osmotic pressure system 4, a rock sample volume change test system 5, and a sound velocity system. Test the system in real time.

The confining pressure system 1 includes a confining pressure cylinder 11 whose lower end is an open end. The top of the confining pressure cylinder 11 is sealed and connected (threaded connection) with two confining pressure pipes 12 communicating with it. The confining pressure oil tank 14 is connected, and a confining pressure pressure gauge 15 and a control valve 16 are installed on the confining pressure pipeline 12 ;

After the confining pressure pump 13 is turned on, the oil in the confining pressure cylinder 11 will be filled first, and then the oil will be stored in the other confining pressure pipeline 12. The oil in the confining pressure pipeline 12 can be used for the voltage stabilization mechanism. 17 An upward force.

The rock sample clamping mechanism 2 includes a lower clamping seat 22 and an upper clamping seat 21 fixed on the top of the hydraulic cylinder. The diameter of the upper end of the lower clamping seat 22 is larger than the diameter of the lower end; the upper clamping seat 21 is a cylindrical structure, Both the upper clamping seat 21 and the lower clamping seat 22 are provided with water inlet holes 211 therethrough in the axial direction. The two water inlet holes 211 are both funnel-shaped, and both ends of the rock sample are sealed and installed at the large hole ends of the water inlet holes 211 .

The axial compression system 3 includes an axial compression cylinder 31, and the top of the axial compression cylinder 31 is sealed and connected with two axial compression pipelines 32 communicating with it. An axial pressure pressure gauge 35 and a control valve 16 are installed on the axial pressure pipeline 32 ;

After the axial pressure pump 33 is turned on, the oil in the axial pressure cylinder 31 will be filled first, and when the oil in the axial pressure cylinder 31 reaches a certain pressure, it will drive the lower clamping seat 22 to move upward, so as to realize the adjustment of the rock sample. After the axial pressure cylinder 31 is filled with oil, the oil will be stored in the other axial pressure pipeline 32, and the oil in the axial pressure pipeline 32 can give its corresponding voltage stabilization mechanism 17 an upward pressure strength.

The osmotic pressure system 4 includes osmotic pressure pipes 41 penetrating the confining pressure cylinder 11 and the axial pressure cylinder 31 respectively, and sealingly connected with the corresponding water inlet holes 211 . One end of the two osmotic pressure pipes 41 passes through the osmotic pressure pump 42 and the osmotic pressure water tank 43 . Connect, and install the osmotic pressure gauge 44 and the control valve 16 on the osmotic pressure pipeline 41; the end of the other end of the two osmotic pressure pipelines 41 is installed with a voltage stabilizing mechanism 17;

Similarly, when the osmotic pressure system 4 is filled with water, it also fills the water in the water inlet hole 211 first, and then the osmotic pressure pipeline 41 is adjacent to the voltage stabilization mechanism 17 to enter the water, and the oil in the osmotic pressure pipeline 41 passes through. An upward force can be given to its corresponding stabilizing mechanism 17 .

When the load applied by the osmotic pressure system 4 located on the upper part of the rock sample is greater than the load applied by the lower part of the rock sample, the rock sample is subjected to forward osmotic pressure; otherwise, the rock sample is subjected to reverse osmotic pressure.

The top end of the axial pressure cylinder 31 is provided with a mounting hole 311 for the lower end of the lower clamping seat 22 to enter. , the two are connected in a sealed manner; all pumps (confining pressure pump 13, axial pressure pump and osmotic pump), control valves and pressure gauges (confining pressure pressure gauge, axial pressure pressure gauge and osmotic pressure pressure gauge) are connected with the processor.

When using this scheme for experiments, after placing the rock sample, the axial compression system 3 needs to be activated first, and the rock sample can be clamped by the pressure provided by the oil in the axial compression system 3, and then other simulation experiments can be carried out. .

The rock sample volume change test system 5 includes a circumferential displacement sensor 51 for collecting the radial displacement of the rock sample and an axial displacement sensor 52 for collecting the axial displacement of the rock sample. The circumferential displacement sensor 51 and the axial displacement The sensors 52 are all connected to the processor.

The rock sample volume change testing system 5 is mainly used for collecting the axial and radial displacement changes of the rock sample when the axial compression system 3 applies multi-stage axial compression.

As shown in Figure 2, the sound velocity real-time testing system includes an ultrasonic signal transmitter 61 and an ultrasonic signal receiver 62 respectively installed at both ends of the rock sample; the ultrasonic signal receiver 62 is connected to the data collector and the pulse receiver controller through a digital phosphor oscilloscope The pulse receiving controller is connected with the ultrasonic signal transmitter 61 and the data collector; the pulse receiving controller and the data collector are both connected with the processor.

The outer surfaces of the ultrasonic signal transmitter 61 and the ultrasonic signal receiver 62 are coated with an anti-rust layer, wherein the anti-rust layer can be zinc plated on the outer surfaces of the transmitter and receiver; the confining pressure pipeline 12, the axial pressure pipeline 32 and the osmotic pressure The pipes 41 can be made of hoses; the three types of pressure gauges and all the control valves 16 can be made of high-strength stainless steel.

During implementation, it is preferred that the voltage stabilization mechanism 17 of this scheme includes a pressure rod 171 placed on the pipeline and placed in the pipeline (containing pressure pipeline, osmotic pressure pipeline and axial pressure pipeline), and the pressure rod 171 is applied upward under the action of the pipeline liquid pressure. One end of the pressing rod 171 is hinged on the base 173, and the other end is provided with a force applying part 174. Preferably, the biasing portion 174 is a weight.

As shown in FIG. 3 , the outer surface of the lower end of the confining pressure cylinder 11 is provided with a flange, and the top end of the axial pressure cylinder 31 is provided with an installation groove surrounding the installation hole 311; the lower end of the confining pressure cylinder 11 is installed in the installation groove, and passes through multiple A threaded connection through the flange is fixed on the top of the axial pressure cylinder 31 . In order to ensure the sealing connection of the two cylinders, a sealing ring can be arranged in the installation groove.

The solution also provides a method for testing water immersion of rocks at different depths by a deep high-stress and high-permeability environment simulation experiment system, including steps 101 to 106 .

In step 101, the first set axial preload force, the first preset osmotic pressure and the first preset confining pressure corresponding to the simulated occurrence depth of the rock sample are obtained; then the rock sample is tightly wrapped with a heat shrinkable film The cylindrical surface is placed on the lower clamping seat 22.

The occurrence depth can be selected according to the specific simulated environment, such as 100m, 1000m, 1400m, 1800m, 2400m, but each time a different occurrence depth is selected, it is necessary to perform steps 101 to 106 during the experiment to complete Immersion of rock samples at an occurrence depth.

In step 102, the first set axial pre-tightening force is applied through the force applying part 174 of the axial pressure system 3, and the axial pressure pump 33 is turned on to add oil into the axial pressure cylinder 31. When the pressure of the axial pressure pressure gauge 35 is equal to When the axial preload is first set, the axial pressure pump 33 is turned off.

When the force-applying portion 174 is a weight, the formula for converting the first set axial preload into the weight of the weight is:

F ₁ =2x ₁ A ₁ /l ₁ , wherein F ₁ is the force applied to the right end of the pressing rod 171 of the axial compression system 3 , l ₁ is the length of the pressing rod 171 of the axial compression system 3 , and x ₁ is the axial pressure The distance between the piston 172 of the system 3 and the base 173 , A ₁ is the bottom area of the piston 172 of the axial compression system 3 .

In step 103, the first preset confining pressure is applied by the force applying part 174 of the confining pressure system 1, and the confining pressure pump 13 is turned on to add oil into the confining pressure cylinder 11. When the pressure of the confining pressure gauge 15 is equal to the first preset confining pressure When setting the confining pressure, close the confining pressure pump 13;

When the force-applying portion 174 is a weight, the formula for converting the first preset confining pressure into the weight of the weight is:

F ₂ =σ ₂ x ₂ A ₂ /l ₂ , where F ₂ is the force applied to the right end of the compression rod 171 of the confining pressure system 1 , σ ₂ is the confining pressure of the rock sample, and l ₂ is the confining pressure system 1 The length of the pressure rod 171, x ₂ is the distance between the piston 172 of the confining pressure system 1 and the base 173, and A ₂ is the bottom area of the piston 172 of the confining pressure system 1.

In step 104, the first preset pressure and the second preset pressure are respectively applied by the two force applying parts 174 of the osmotic pressure system 4, and the two osmotic pressure pumps 42 are turned on to supply water to the osmotic pressure pipeline 41 and the water inlet hole 211 , when the pressures of the two osmotic pressure gauges 44 are equal to the pressure exerted by their corresponding force-applying parts, the two osmotic pressure pumps 42 are closed; wherein, the pressure difference between the first preset pressure and the second preset pressure for osmotic pressure.

When the force-applying portion 174 is a weight, the formula for converting the first set axial preload into the weight of the weight is:

F ₃ =σ ₃ x ₃ A ₃ /l ₃ , F _{4 =} σ ₄ x _{4 A 4} /l ₄ , σ ₅ =|σ ₃ -σ ₄ | The force at the right end of the two compression rods 171 of system 4, σ ₃ and σ ₄ are the pressures on the upper and lower parts of the rock sample, respectively, σ ₅ is the osmotic pressure of the rock sample, and l ₃ and l ₄ are the osmotic pressures of the system 4, respectively. The length of the pressure rod 171 , x ₃ and x ₄ are the distances between the two pistons 172 of the osmotic pressure system 4 and the base 173 respectively, and A ₃ and A ₄ are the bottom areas of the two pistons 172 of the osmotic pressure system 4 , respectively.

In step 105, when the immersion time does not reach the target number of test days, if the numerical fluctuation of the axial pressure pressure gauge 35, the confining pressure pressure gauge 15 or the osmotic pressure pressure gauge 44 is not equal to the set threshold value, the axial pressure pump 33 and the confining pressure pressure gauge 44 are turned on. The pressure pump 13 or the osmotic pressure pump 42 replenishes the liquid until the values of the axial pressure pressure gauge 35, the confining pressure pressure gauge 15 or the osmotic pressure pressure gauge 44 return to the original pressure (the pressure before the fluctuation);

In step 106, when the immersion time reaches the target experimental days, open the control valves 16 of the axial pressure system 3, the confining pressure system 1 and the osmotic pressure system 4, and start the axial pressure pump 33, the confining pressure pump 13 and the osmotic pressure pump 42 to pump Return the liquid and remove the rock sample.

After the water seepage experiment is completed, a small amount of liquid in the seepage tank can be absorbed, and the chemical composition, mineral (XRD), and element (XRF) analysis of the soaking solution can be carried out to reveal the dissolution process of mineral components under the combination of true stress and seepage pressure at different occurrence depths. The evolution law of transitivity composition, to prove the physical influence mechanism of water infiltration on rock microstructure under high stress and high osmotic pressure conditions, and to reveal rock mineral expansion and lubrication under the action of high stress environment and high pressure water.

In order to restore the deep characteristics, based on the rock samples of the five different occurrence depths (100m, 1000m, 1400m, 1800m, 2400m) in the water immersion test, the triaxial rheological test of the deep high stress and high permeability environment is carried out, and the realization method includes step S1 Go to step S8. The triaxial rheological test was carried out based on the rock samples obtained from the water immersion test at different occurrence depths.

In step S1, the rock sample obtained by the water immersion test is placed on the lower clamping seat 22, the second set axial pre-tightening force is applied through the force applying part 174 of the axial pressure system 3, and the axial pressure pump 33 is turned on to the shaft. Oil is added into the pressure cylinder 31, and when the pressure of the axial pressure gauge 35 is equal to the second set axial preload, the axial pressure pump 33 is turned off;

In step S2, the axial displacement sensor 52 and the circumferential displacement sensor 51 are installed on the rock sample, the circumferential displacement sensor 51 needs to be kept horizontal with the bottom surface of the rock sample, and the axial displacement sensor 52 needs to be parallel to the axis of the rock sample , and adjust the axial displacement and hoop displacement measurement system to the initial value;

Based on the above operations, the vertical fixation of the rock sample is completed to facilitate subsequent tests.

In step S3, the second preset confining pressure is applied by the force applying part 174 of the confining pressure system 1, and the confining pressure pump 13 is turned on to add oil into the confining pressure cylinder 11. When the pressure of the confining pressure gauge 15 is equal to the second preset confining pressure When setting the confining pressure, close the confining pressure pump 13;

In step S4 , the two force applying parts 174 of the osmotic pressure system 4 are used to apply the third preset pressure and the fourth preset pressure respectively, and the two osmotic pressure pumps 42 are turned on to supply water to the osmotic pressure pipeline 41 and the water inlet hole 211 . , when the pressures of the two osmotic pressure gauges 44 are equal to the pressure exerted by their corresponding force-applying parts, the two osmotic pressure pumps 42 are closed; wherein, the pressure difference between the third preset pressure and the fourth preset pressure for osmotic pressure.

In step S5, after the values of the axial pressure pressure gauge 35, the confining pressure pressure gauge 15 or the osmotic pressure pressure gauge 44 are stable, start the sound velocity real-time testing system to measure the dynamic sound velocity information of the rock sample during the long-term creep process, Its implementation principle is:

The ultrasonic signal transmitting sensor sends a pulse signal through the pulse receiving controller, which propagates to the ultrasonic signal receiving sensor in the rock sample, and the time taken is recorded by the data collector. displayed in. Taking the occurrence depth of 100m as an example, the obtained sound velocity change data of rock creep test are plotted in Fig. 4. The wave velocity of the sound wave decreases with the development of medium cracks, the density decreases, and the acoustic impedance increases, and it increases with the increase of stress and density. Therefore, acquiring the real-time acoustic data of the whole process of rock creep can reflect the damage and deterioration properties of the rock, so as to better reveal the long-term creep and seepage mechanical behavior characteristics of the rock.

In step S6, a preset axial pressure is applied by the force applying part 174 of the axial pressure system 3, the axial pressure pump 33 is turned on, and oil is added into the axial pressure cylinder 31 until the axial displacement sensor 52 and the circumferential displacement sensor 51 collect the data stability;

In step S7, observe whether the rock sample is damaged, if not, set the preset axial pressure=preset axial pressure+set axial load, return to step S6, otherwise go to step S8;

It is preferable to set the axial load to 10MP; in the process of applying the axial force to the axial compression system 3, it is necessary to record the changes of the axial strain and hoop strain with time in the whole process of the experiment, and calculate the volumetric strain of the rock sample throughout the whole process based on this. Changes with time, where volume strain = axial strain + 2 × hoop strain, the axial strain is a positive value, and the hoop strain is a negative value.

In step S8, open the control valves 16 of the axial pressure system 3, the confining pressure system 1 and the osmotic pressure system 4, start the axial pressure pump 33, the confining pressure pump 13 and the osmotic pressure pump 42 to withdraw the liquid, take out the rock sample, and observe the The failure form of the rock sample.

Taking the occurrence depth of 100m as an example, the data obtained from the entire creep process of the rock sample at this occurrence depth are plotted in Figure 5, the characteristics of the curve are analyzed, the long-term strength of the rock is determined, and the stress-seepage-fracture of the surrounding rock at different occurrence depths is explored. -Creep coupling mechanism, revealing rock damage and failure characteristics and creep seepage mechanical behavior characteristics under high stress and high osmotic pressure conditions, so as to serve the long-term safe and stable operation of deep underground engineering.

During implementation, this scheme preferably starts the sound velocity real-time test system, and also includes observing whether the numerical fluctuation of the axial pressure gauge 35, the confining pressure gauge 15 or the osmotic pressure gauge 44 is not equal to the set threshold; if not, continue the experiment;

If so, open the axial pressure pump 33, the confining pressure pump 13 or the osmotic pressure pump 42 to replenish the liquid, until the value of the axial pressure pressure gauge 35, the confining pressure pressure gauge 15 or the osmotic pressure pressure gauge 44 restores the original pressure.

Claims (7)

1. Deep high stress high-permeability environmental simulation experiment system, its characterized in that includes:

the confining pressure system comprises a confining pressure cylinder with the lower end as an open end, the top of the confining pressure cylinder is hermetically connected with two confining pressure pipelines communicated with the confining pressure cylinder, one confining pressure pipeline is communicated with a confining pressure oil tank through a confining pressure pump, and a confining pressure gauge and a control valve are installed on the confining pressure pipeline; the tail end of the other confining pressure pipeline is provided with a pressure stabilizing mechanism;

the rock sample clamping mechanism comprises a lower clamping seat and an upper clamping seat fixed at the top in the oil hydraulic cylinder, wherein the diameter of the upper end of the lower clamping seat is larger than that of the lower end of the lower clamping seat; the upper clamping seat and the lower clamping seat are axially provided with water inlet holes penetrating through the upper clamping seat and the lower clamping seat;

the shaft pressure system comprises a shaft pressure cylinder, the top of the shaft pressure cylinder is hermetically connected with two shaft pressure pipelines communicated with the shaft pressure cylinder, one shaft pressure pipeline is communicated with a shaft pressure oil tank through a shaft pressure pump, and a shaft pressure gauge and a control valve are arranged on the shaft pressure pipeline; the tail end of the other axial pressure pipeline is provided with a pressure stabilizing mechanism;

the osmotic pressure system comprises osmotic pressure pipelines which penetrate into the surrounding pressure cylinder and the axial pressure cylinder respectively and are in sealing connection with the corresponding water inlet holes, one ends of the two osmotic pressure pipelines are communicated with the osmotic pressure water tank through osmotic pressure pumps, and an osmotic pressure gauge and a control valve are arranged on the osmotic pressure pipelines; the tail ends of the other ends of the two osmotic pressure pipelines are provided with pressure stabilizing mechanisms;

the top end of the shaft pressure cylinder is provided with an installation hole for the lower end of the lower clamping seat to enter, the lower end of the lower clamping seat is movably and hermetically installed in the installation hole, the surrounding pressure cylinder is installed at the top end of the shaft pressure cylinder, and the surrounding pressure cylinder and the shaft pressure cylinder are hermetically connected; all the pumps, the control valves and the pressure gauge are connected with the processor.

2. The deep high-stress high-permeability environment simulation experiment system according to claim 1, further comprising a rock sample volume change testing system, wherein the rock sample volume change testing system comprises a circumferential displacement sensor for acquiring radial displacement of the rock sample and an axial displacement sensor for acquiring axial displacement of the rock sample, and the circumferential displacement sensor and the axial displacement sensor are both connected with the processor.

3. The deep high-stress high-permeability environment simulation experiment system according to claim 1, further comprising a sound velocity real-time testing system, which comprises an ultrasonic signal transmitter and an ultrasonic signal receiver respectively installed at two ends of the rock sample; the ultrasonic signal receiver is respectively connected with the data acquisition unit and the pulse receiving controller through the digital fluorescence oscilloscope, and the pulse receiving controller is connected with the ultrasonic signal transmitter and the data acquisition unit; and the pulse receiving controller and the data acquisition unit are both connected with the processor.

4. The deep high-stress high-permeability environment simulation experiment system according to claim 3, wherein the outer surfaces of the ultrasonic signal transmitter and the ultrasonic signal receiver are coated with an anti-rust layer.

5. The deep high-stress high-permeability environment simulation experiment system according to claim 1, wherein the pressure stabilizing mechanism comprises a pressure rod placed on the pipeline and a piston placed in the pipeline and applying an upward force to the pressure rod under the action of the pressure of the pipeline liquid; one end of the pressure rod is hinged to the base, and the other end of the pressure rod is provided with a force application part.

6. The deep high-stress high-permeability environment simulation experiment system according to claim 5, wherein the force application part is a weight.

7. The deep high-stress high-permeability environment simulation experiment system according to any one of claims 1 to 5, wherein a flange is arranged on the outer surface of the lower end of the confining pressure cylinder, and an installation groove surrounding the installation hole is formed in the top end of the axial pressure cylinder; the lower end of the enclosing and pressing cylinder is arranged in the mounting groove and is fixed at the top of the shaft pressing cylinder through a plurality of threaded connecting pieces penetrating through the flange plate.

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