A multi-stage water-containing simulated lunar soil stress aging strengthening preparation device and method

Abstract

This invention proposes a multi-stage stress-aging hardening device and method for preparing hydrated simulated lunar soil, belonging to the field of hydrated simulated lunar soil preparation. The device includes a compaction mechanism, a stress-aging hardening tool, a low-temperature storage refrigerator, a sample barrel, monitoring equipment, strain gauges, and a temperature sensor. The sample barrel is placed inside and compacted by the compaction mechanism. The stress-aging hardening tool includes an upper support cover, a screw, and a pressure plate. The upper support cover is positioned above the sample barrel and connected to the screw, which is threadedly connected to a round nut, which is connected to the pressure plate. The pressure plate is moved by rotating the screw, pressurizing the sample inside the sample barrel. The pressurized sample, along with the stress-aging hardening tool and sample barrel, is placed in a low-temperature storage refrigerator. The device is primarily used for preparing simulated lunar soil through stress-aging hardening.

Description

Technical Field

[0001] The present invention belongs to the field of preparation of water-containing simulated lunar soil, and in particular relates to a multi-stage stress aging strengthening preparation device and method for water-containing simulated lunar soil. Background Art

[0002] With the increasingly stringent technical requirements for cross-section sample preparation, the cold water ice in the sample breaks during the preparation process, causing the particles to lose their adhesion, resulting in low sample strength and hardness that cannot meet the requirements. Therefore, it is necessary to pressurize the sample in a low-temperature environment to improve the sample's strength and density to meet the test requirements. After the sample is frozen at low temperatures, the sample volume will expand, resulting in the loss of sample density, density uniformity, and sample integrity. The sample will no longer meet the test requirements, making it impossible to ensure the integrity of subsequent tests and the accuracy of the data.

[0003] Currently, there is a need for a solution that can ensure that the density, moisture content, strength and hardness of the sample do not change during the sample preparation process. Ensuring that the sample does not crack has become a technical problem that urgently needs to be solved at this stage. Summary of the Invention

[0004] In view of this, the present invention aims to propose a multi-stage water-containing simulated lunar soil stress aging strengthening preparation device and method to solve the problems existing in the prior art.

[0005] To achieve the above objectives, the present invention adopts the following technical solutions: a multi-stage stress aging hardening preparation device for simulated lunar soil containing water, comprising a compaction mechanism, a stress aging hardening tool, a low-temperature storage refrigerator, a sample barrel, a monitoring device, a strain gauge, and a temperature sensor. A sample is placed in the sample barrel and compacted by the compaction mechanism. The stress aging hardening tool comprises an upper support cover, a screw rod, and a pressure plate. The upper support cover is provided above the sample barrel and connected to the screw rod. The screw rod is threadedly connected to a round nut, which is connected to the pressure plate. The pressure plate is moved by rotating the screw rod to pressurize the sample in the sample barrel. The pressurized sample, together with the stress aging hardening tool and the sample barrel, is placed in a low-temperature storage refrigerator. Multiple strain gauges are provided below the pressure plate and on the inner wall and bottom of the sample barrel. Multiple temperature sensors are provided on the sample barrel. The strain gauges and temperature sensors are respectively connected to the monitoring device via low-temperature transmission lines.

[0006] Furthermore, the compacting mechanism includes a hydraulic press, a pressing block and a liquid nitrogen refrigeration mechanism, the output end of the hydraulic press is connected to the pressing block, the pressing block compacts the sample in the sample barrel, and the sample barrel is connected to the liquid nitrogen refrigeration mechanism.

[0007] Furthermore, the liquid nitrogen refrigeration mechanism includes a liquid nitrogen tank and a liquid nitrogen recovery barrel, the side wall of the sample barrel is provided with a liquid nitrogen inlet and a liquid nitrogen outlet, the side wall of the sample barrel is provided with a liquid nitrogen tank, the liquid nitrogen inlet and the liquid nitrogen outlet are connected to the liquid nitrogen tank, and the liquid nitrogen outlet is connected to the liquid nitrogen recovery barrel.

[0008] Furthermore, the monitoring device includes a temperature monitoring device and a pressure detection device, the temperature sensor is connected to the temperature monitoring device, and the strain gauge is connected to the pressure detection device.

[0009] Furthermore, the outer side of the round nut is connected to the bearing, the bearing is connected to the bearing support, a bearing end cover is provided on the upper part of the bearing, the bearing end cover is connected to the pressure plate through a fastening bolt, a plurality of disc springs are provided between the lower part of the bearing support and the pressure plate, and a handle is provided on the upper part of the screw rod.

[0010] Furthermore, the number of the disc springs is eight, and the eight disc springs are symmetrically arranged with four on the upper part and four on the lower part.

[0011] Furthermore, the strain gauges attached to the inner wall of the sample barrel are arranged in a 3×3 three-layer array, with three strain gauges set on each layer and adjacent strain gauges spaced 120° apart. There are three strain gauges attached to the bottom of the sample barrel, which are attached around the bottom circle of the barrel with an interval of 120° around the center of the bottom circle of the barrel. There are three strain gauges attached to the bottom of the pressure plate, which are distributed at an interval of 120° between each other.

[0012] Furthermore, a strain gauge groove is opened on the inner wall of the sample barrel, the strain gauge is arranged in the strain gauge groove, the strain gauge is adhered to the strain gauge groove by low-temperature resistant glue, and the sealing part of the low-temperature transmission line is sealed by low-temperature resistant glue.

[0013] Furthermore, the strain gauge includes two upper and lower resin substrates and a sensitive grid, and the sensitive grid is arranged between the upper and lower resin substrates.

[0014] The present invention also provides a method for preparing a multi-stage water-containing simulated lunar soil stress aging hardening preparation device, which comprises the following steps:

[0015] Step 1: First, add liquid nitrogen into the liquid nitrogen tank on the side wall of the sample barrel to pre-cool the sample barrel, and then place the sample barrel under the hydraulic press;

[0016] Step 2: Pour one-third of the total crushed ice particle sample into the sample bucket, start the hydraulic press, and pressurize the sample in the sample bucket. When the pressure data transmitted by the strain gauge reaches the set value, stop pressurizing, lift the pressure block, and continue adding samples. This process needs to be repeated three times. During this process, the sample pressure and temperature are monitored in real time. At this point, the sample is a first-level sample;

[0017] Step 3: Place the stress aging hardening tool in a liquid nitrogen bath to pre-cool it, then install the stress aging hardening tool on the sample barrel, and continuously stress the first-level sample by applying pressure through the pressure plate.

[0018] The pressurized sample, together with the stress aging strengthening tooling and sample barrel, is then placed in a low-temperature storage refrigerator for continuous loading for 24 hours, and the temperature is monitored in real time. At this point, the sample is a secondary sample and the preparation is complete.

[0019] Compared with the existing technology, the beneficial effects of the present invention are: a multi-stage water-containing simulated lunar soil stress aging strengthening preparation device designed by the present invention can generate a measurable confining pressure on the sample during the sample preparation process, and provide a guarantee for the integrity of various performance indicators of the sample. It provides a good foundation for the next step of sample stacking. The present invention is mainly to solve the problem that the strength, hardness, density and sample integrity of the sample are disturbed during the preparation process, so that the sample can meet the requirements of subsequent experiments. The present invention can restore the density and uniformity of the sample through the corresponding preparation method under the premise of ensuring the integrity of the sample.

[0020] When the compacting mechanism of the present invention is compacting, a layered compaction method is adopted to compact the lunar soil sample three times. This compaction method can make each part of the sample subject to the same force, make the relative density of the overall sample more uniform, and make the strength and hardness of the entire sample the same. The compacted sample is subjected to long-term low-temperature compaction through a stress aging strengthening tool and a sample barrel, which can improve the strength and hardness of the sample, and prevent the sample from frost heave and cracking during the freezing process, resulting in damage to the density and integrity of the sample. High-precision stress and temperature sensors are used throughout the preparation process, which can control the pressurization stop time and liquid nitrogen flux in real time, so that the density and temperature of the sample are closer to the required values. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings, which constitute part of the present invention, are provided to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are provided to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0022] Figure 1 Schematic diagram of the compaction mechanism structure of the present invention;

[0023] Figure 2 This is a schematic diagram of the process of compacting a sample by the compacting mechanism of the present invention;

[0024] Figure 3 This is a schematic diagram of the stress aging strengthening tooling structure of the present invention;

[0025] Figure 4This is a structural diagram of the connection between the screw rod and the pressure plate of the present invention;

[0026] Figure 5 This is a schematic diagram of the sample barrel structure of the present invention;

[0027] Figure 6 This is a schematic diagram of the top view of the bottom of the sample barrel according to the present invention;

[0028] Figure 7 This is a schematic diagram of the main structure of the strain gauge of the present invention attached to the side wall of the gland;

[0029] Figure 8 This is a schematic diagram of the top view of the structure of the strain gauge attached to the side wall of the gland according to the present invention;

[0030] Figure 9 This is a schematic diagram of the cross-sectional structure of the strain gauge of the present invention attached to the side wall of the sample barrel;

[0031] Figure 10 This is a schematic diagram of the axonometric structure of the strain gauge of the present invention attached to the side wall of the sample barrel;

[0032] Figure 11 This is a side view structural diagram of the strain gauge of the present invention attached to the side wall of the sample barrel.

[0033] 1-Hydraulic press, 2-Pressing block, 3-Liquid nitrogen tank, 4-Sample barrel, 5-Liquid nitrogen recovery barrel, 6-Monitoring equipment, 7-Temperature monitoring equipment, 8-Pressure detection equipment, 9-Upper support cover, 10-Handle, 11-Screw rod, 12-Cryogenic transmission line, 13-Fasten bolt, 14-Bearing end cover, 15-Bearing, 16-Pressure plate, 17-Round nut, 18-Bearing support, 19-Disc spring, 20-Liquid nitrogen inlet, 21-Liquid nitrogen outlet, 22-Strain gauge, 23-Temperature sensor, 24-Strain gauge slot, 25-Cryogenic adhesive, 26-Resin base, 27-Sensitive grid. DETAILED DESCRIPTION

[0034] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely explain the technical solutions in the embodiments of the present invention. It should be noted that the embodiments of the present invention and the features therein can be combined with each other in the absence of conflict, and the embodiments described are only part of the embodiments of the present invention, not all of the embodiments.

[0035] See also Figure 1-11This embodiment describes a multi-stage stress aging hardening preparation device for simulated lunar soil containing water, which includes a compaction mechanism, a stress aging hardening tool, a low-temperature storage refrigerator, a sample barrel 4, a monitoring device 6, a strain gauge 22, and a temperature sensor 23. The sample is placed in the sample barrel 4, and the sample in the sample barrel 4 is compacted by the compaction mechanism. The stress aging hardening tool includes an upper support cover 9, a screw rod 11, and a pressure plate 16. The upper support cover 9 is set above the sample barrel 4, and the upper support cover 9 is connected to the screw rod 11. The screw rod 11 is connected to the sample barrel 4. The round nut 17 is threadedly connected, and the round nut 17 is connected to the pressure plate 16. The pressure plate 16 is moved by rotating the screw 11 to pressurize the sample in the sample barrel 4. The pressurized sample is placed in a low-temperature storage refrigerator together with the stress aging strengthening tooling and the sample barrel 4. A plurality of strain gauges 22 are provided below the pressure plate 16 and on the inner wall and bottom of the sample barrel 4. A plurality of temperature sensors 23 are provided on the sample barrel 4. The strain gauges 22 and the temperature sensors 23 are respectively connected to the monitoring equipment 6 through the low-temperature transmission line 12.

[0036] The compaction mechanism includes a hydraulic press 1, a compacting block 2, and a liquid nitrogen refrigeration mechanism. The output of the hydraulic press 1 is connected to the compacting block 2, which compacts the sample in a sample barrel 4. The sample barrel 4 is connected to the liquid nitrogen refrigeration mechanism. The compaction process is carried out in three steps, with each filling amount accounting for one-third of the total sample volume.

[0037] The liquid nitrogen refrigeration mechanism includes a liquid nitrogen tank 3 and a liquid nitrogen recovery barrel 5. The side wall of the sample barrel 4 is provided with a liquid nitrogen inlet 20 and a liquid nitrogen outlet 21. A liquid nitrogen tank is provided inside the side wall of the sample barrel 4. The liquid nitrogen inlet 20 and the liquid nitrogen outlet 21 are connected to the liquid nitrogen tank. The liquid nitrogen inlet 20 is connected to the liquid nitrogen tank 3, and the liquid nitrogen outlet 21 is connected to the liquid nitrogen recovery barrel 5. The liquid nitrogen tank facilitates the circulation of liquid nitrogen from the side wall cavity.

[0038] The monitoring device 6 includes a temperature monitoring device 7 and a pressure detection device 8. The temperature sensor 23 is connected to the temperature monitoring device 7, and the strain gauge 22 is connected to the pressure detection device 8. The internal pressure and temperature of the sample are connected to the monitoring device 6 via a signal transmission line connected to the sensor, and the sample pressure and temperature data are displayed on a computer screen.

[0039] The outer side of the round nut 17 is connected to the bearing 15, and the bearing 15 is connected to the bearing support 18. A bearing end cover 14 is provided on the upper portion of the bearing 15, and the bearing end cover 14 is connected to the pressure plate 16 via a fastening bolt 13. A plurality of disc springs 19 are provided between the lower portion of the bearing support 18 and the pressure plate 16. A handle 10 is provided on the upper portion of the screw rod 11. Preferably, the number of the disc springs 19 is eight, and the eight disc springs 19 are symmetrically arranged with four on the upper portion and four on the lower portion.

[0040] The strain gauges 22 attached to the inner wall of the sample barrel 4 are arranged in a 3×3 three-layer array, with three strain gauges 22 set in each layer, and the interval between adjacent strain gauges 22 is 120°. The number of strain gauges 22 attached to the bottom of the sample barrel 4 is three, and they are attached around the bottom circle of the barrel with the center of the barrel bottom as the center and the interval of 120°. The number of strain gauges 22 attached to the bottom of the pressure plate 16 is three, and they are distributed at an interval of 120° between two.

[0041] The inner wall of the sample barrel 4 defines a strain gauge slot 24, within which the strain gauge 22 is disposed. The strain gauge 22 is adhered to the slot 24 with a low-temperature-resistant adhesive 25, and the seal of the low-temperature transmission line 12 is sealed with the low-temperature-resistant adhesive 25. The strain gauge 22 includes upper and lower resin substrates 26 and a sensitive grid 27, disposed between the upper and lower resin substrates 26.

[0042] Preferably, the sample barrel 4 is made of 4340 steel, which is resistant to ultra-low temperatures. The inner wall of the sample barrel 4 is provided with scale lines, which can intuitively reflect the compression amount of the ice particle sample, and the relative density of the sample is calculated by the total mass and compression amount of the ice particle sample.

[0043] This embodiment provides a method for preparing a multi-stage water-containing simulated lunar soil stress aging hardening preparation device, which includes the following steps:

[0044] Step 1: First, liquid nitrogen is introduced into the liquid nitrogen tank on the side wall of the sample barrel 4 to pre-cool the sample barrel 4, and the sample barrel 4 is placed under the hydraulic press 1;

[0045] Step 2: Pour one-third of the total crushed ice particle sample into the sample bucket 4, start the hydraulic press 1, and pressurize the sample in the sample bucket 4. When the pressure data transmitted by the strain gauge 22 reaches the set value, stop pressurizing, lift the pressure block 2, and continue adding samples. This process needs to be repeated three times. During this process, the sample pressure and temperature are monitored in real time. At this time, the sample is a first-level sample;

[0046] Step 3: Place the stress aging hardening tool in a liquid nitrogen bath environment for pre-cooling, then install the stress aging hardening tool on the sample barrel 4, and continuously stress the first-level sample by applying pressure through the pressure plate 16.

[0047] The pressurized sample, together with the stress aging strengthening tooling and the sample barrel 4, is then placed in a low-temperature storage refrigerator for continuous loading for 24 hours, and the temperature is monitored in real time. At this point, the sample is a secondary sample and the preparation is complete.

[0048] like Figure 1 and 2As shown, a primary sample is prepared using a compaction mechanism. In a low-temperature environment provided by liquid nitrogen, the primary ice-containing raw material is weighed according to density and poured into a sample barrel 4 in three batches. The top surface of the soil layer is leveled. After the first one-third of the sample is filled, hydraulic press 1 is activated to compact the sample in barrel 4. After compaction reaches the corresponding position calculated on the scale line of sample barrel 4, loading is stopped and pressure is maintained for 30 seconds. Then, press block 2 on hydraulic press 1 is lifted and refilled with ice-containing raw material. This process is repeated three times until the three layers of sample are pressed to the corresponding scale lines. This layered compaction method ensures more uniform force distribution and a more uniform density throughout the sample. When press block 2 is lifted, the surface of the compacted lunar soil layer is scraped to eliminate the interfaces between the layers. Throughout this process, the sample temperature is monitored in real time to adjust the liquid nitrogen flux accordingly.

[0049] like Figure 3 As shown, a secondary sample is prepared using a stress aging hardening tool. After the primary sample is prepared, compressive stress is applied to the sample by rotating the screw 11. The displacement of the load corresponds to the applied pressure. During the pressurization process, the sample environmental parameters are monitored by a temperature sensor and a low-temperature strain gauge 22. When the screw 11 reaches a certain position, it is transferred to a low-temperature storage refrigerator with gradient cooling for aging hardening to prevent sample rebound and cracking.

[0050] like Figure 4 As shown, when the screw 11 rotates and presses downward, it drives the thrust bearing 15, the bearing support 18, and a certain number of disc springs 19 downward to compact the sample containing ice particles. During the compaction process, the disc springs 19 act as a buffer to prevent large impact forces from damaging the pressure plate 16 and the screw 11. The disc springs 19 are symmetrically distributed in a pattern of 4 on top and 4 on the bottom. This distribution of disc springs 19 can withstand a pressure that is 4 times that of a single disc spring 19 and can accept a downward stroke that is twice that of a single disc spring 19, which can meet the downward pressure requirements of the entire device. When the sample is compacted and the pressure plate 16 needs to be lifted, the round nut 17 at the bottom of the screw 11 drives the bearing 15 and the bearing end cover 14 to lift the pressure plate 16, separating the pressure plate 16 from the sample.

[0051] like Figure 5 As shown, the strain gauges 22 attached to the inner wall of the sample barrel 4 are arranged in a 3×3 array on the side wall of the sample barrel 4, with three strain gauges 22 attached to each layer. Adjacent strain gauges 22 are spaced 120 degrees apart, resulting in a total of nine strain gauges 22 attached to the inner wall of the sample barrel 4. This attachment method allows stress measurements at various locations on the sample, and the average value is used to estimate the stress within the entire sample, preventing the influence of uneven stress on the sample on the measured parameters.

[0052] like Figure 6As shown, three strain gauges 22 are attached to the bottom of the sample barrel 4, spaced 120 degrees apart around the barrel's bottom circle. This attachment method allows for comprehensive and multi-angle compressive stress measurements at the bottom of the sample, preventing inaccurate single compressive stress measurements due to uneven stress across the entire sample.

[0053] like Figure 7 and 8 As shown, there are three strain gauges attached to the side wall of the pressure plate 16, which are spaced 120 degrees apart. The pressure on the upper part of the entire sample is measured by the contraction of the side wall when the pressure plate 16 is pressed downward.

[0054] like Figure 9-11 As shown, the strain gauge slot 24 in the inner wall of the sample barrel 4 is slightly larger than the strain gauge 22, facilitating its attachment. The strain gauge 22 has a temperature tolerance range of -269°C to 120°C and is bonded to the slot 24 with a low-temperature-resistant adhesive 25. This adhesion prevents shear forces on the strain gauge 22 from being generated by downward pressure on the sample within the sample barrel 4, potentially damaging the strain gauge 22. A low-temperature transmission line 12 extends from the nozzle and connects to the monitoring device 6. The end of the low-temperature transmission line 12 is also sealed with low-temperature-resistant adhesive 25 to prevent sample leakage.

[0055] The ultra-low temperature strain gauge 22 includes two upper and lower resin substrates 27, with a sensitive grid 27 sandwiched between the upper and lower resin substrates 27. When pressure is applied to the resin substrate 27 through the sample, the sensitive grid 27 sandwich produces a slight deformation, and the resistance of the sensitive grid 27 changes, causing the current in the low-temperature transmission line 12 to change, thereby measuring the compressive stress there. The minimum operating temperature of this strain gauge 22 is -269°C, which can fully meet the working requirements in a liquid nitrogen environment.

[0056] The embodiments of the present invention disclosed above are intended only to illustrate the present invention. The embodiments do not describe all details in detail, nor do they limit the present invention to the specific embodiments described. Numerous modifications and variations are possible based on the contents of this specification. These embodiments are selected and described in detail in this specification to better explain the principles and practical applications of the present invention, thereby enabling those skilled in the art to better understand and utilize the present invention.

Claims

1. A method for preparing a multi-stage device for preparing simulated lunar regolith by stress aging, characterized by: The preparation device comprises a compacting mechanism, a stress aging strengthening tool, a low-temperature storage refrigerator, a sample barrel (4), a monitoring device (6), a strain gauge (22) and a temperature sensor (23). A sample is placed in the sample barrel (4), and the sample in the sample barrel (4) is compacted by the compacting mechanism. The stress aging strengthening tool comprises an upper support cover (9), a screw rod (11) and a pressure plate (16). An upper support cover (9) is provided above the sample barrel (4), the upper support cover (9) is connected to the screw rod (11), the screw rod (11) is threadedly connected to a round nut (17), and the round nut (17) is connected to the pressure plate (16). By rotating the screw rod (11), the pressure plate (16) is moved to adjust the pressure in the sample barrel (4). The sample is pressurized, and the pressurized sample is placed in a low-temperature storage refrigerator together with the stress aging strengthening tool and the sample barrel (4). A plurality of strain gauges (22) are provided below the pressure plate (16) and on the inner wall and bottom of the sample barrel (4). A plurality of temperature sensors (23) are provided on the sample barrel (4). The strain gauges (22) and the temperature sensors (23) are respectively connected to the monitoring device (6) through a low-temperature transmission line (12). The compacting mechanism includes a hydraulic press (1), a pressing block (2) and a liquid nitrogen refrigeration mechanism. The output end of the hydraulic press (1) is connected to the pressing block (2). The pressing block (2) compacts the sample in the sample barrel (4). The sample barrel (4) is connected to the liquid nitrogen refrigeration mechanism. The preparation method comprises the following steps: Step 1: First, liquid nitrogen is introduced into the liquid nitrogen tank on the side wall of the sample barrel (4) to pre-cool the sample barrel (4), and the sample barrel (4) is placed under the hydraulic press (1); Step 2: Pour one-third of the total crushed ice particle sample into the sample barrel (4), start the hydraulic press (1), and pressurize the sample in the sample barrel (4). When the pressure data transmitted by the strain gauge (22) reaches the set value, stop pressurizing, lift the pressure block (2), and continue to add samples. This process needs to be repeated 3 times. During this process, the sample pressure and temperature are monitored in real time. At this time, the sample is a first-level sample. Step 3: Place the stress aging hardening tool in a liquid nitrogen bath environment for pre-cooling, then install the stress aging hardening tool on the sample barrel (4), and continuously stress load the first-level sample by applying pressure through the pressure plate (16). The pressurized sample, together with the stress aging strengthening tooling and the sample barrel (4), is then placed in a low-temperature storage refrigerator for continuous loading for 24 hours, and the temperature is monitored in real time. At this point, the sample is a secondary sample and the preparation is complete.

2. The method for preparing a multi-stage stress aging hardening device for preparing water-containing simulated lunar soil according to claim 1, characterized in that: The liquid nitrogen refrigeration mechanism comprises a liquid nitrogen tank (3) and a liquid nitrogen recovery barrel (5); a liquid nitrogen inlet (20) and a liquid nitrogen outlet (21) are provided on the side wall of the sample barrel (4); a liquid nitrogen tank is provided inside the side wall of the sample barrel (4); the liquid nitrogen inlet (20) and the liquid nitrogen outlet (21) are in communication with the liquid nitrogen tank; the liquid nitrogen inlet (20) is connected to the liquid nitrogen tank (3); and the liquid nitrogen outlet (21) is connected to the liquid nitrogen recovery barrel (5).

3. The method for preparing a multi-stage stress aging hardening device for preparing water-containing simulated lunar soil according to claim 1, characterized in that: The monitoring device (6) comprises a temperature monitoring device (7) and a pressure detection device (8), the temperature sensor (23) is connected to the temperature monitoring device (7), and the strain gauge (22) is connected to the pressure detection device (8).

4. The method for preparing a multi-stage stress aging hardening device for preparing water-containing simulated lunar soil according to claim 1, characterized in that: The outer side of the round nut (17) is connected to the bearing (15), the bearing (15) is connected to the bearing support (18), a bearing end cover (14) is provided on the upper part of the bearing (15), the bearing end cover (14) is connected to the pressure plate (16) through a fastening bolt (13), a plurality of disc springs (19) are provided between the lower part of the bearing support (18) and the pressure plate (16), and a handle (10) is provided on the upper part of the screw rod (11).

5. The method for preparing a multi-stage stress aging hardening device for preparing water-containing simulated lunar soil according to claim 4, characterized in that: The number of the disc springs (19) is eight, and the eight disc springs (19) are symmetrically arranged in a manner of four upper portions and four lower portions.

6. The method for preparing a multi-stage stress aging hardening device for preparing water-containing simulated lunar soil according to claim 1, characterized in that: The strain gauges (22) attached to the inner wall of the sample barrel (4) are arranged in a 3×3 three-layer array, with three strain gauges (22) provided on each layer, and adjacent strain gauges (22) are spaced 120° apart. The number of strain gauges (22) attached to the bottom of the sample barrel (4) is three, and they are attached around the bottom circle of the barrel with a spacing of 120° around the center of the bottom circle of the barrel. The number of strain gauges (22) attached to the bottom of the pressure plate (16) is three, and they are distributed with a spacing of 120° between each other.

7. The method for preparing a multi-stage stress aging hardening device for preparing water-containing simulated lunar soil according to claim 1, characterized in that: The inner wall of the sample barrel (4) is provided with a strain gauge groove (24), the strain gauge (22) is arranged in the strain gauge groove (24), the strain gauge (22) is adhered to the strain gauge groove (24) by means of a low-temperature resistant adhesive (25), and the sealing portion of the low-temperature transmission line (12) is sealed by means of the low-temperature resistant adhesive (25).

8. The method for preparing a multi-stage water-containing simulated lunar soil stress aging hardening preparation device according to claim 1, characterized in that: The strain gauge (22) comprises two upper and lower resin substrates (26) and a sensitive grid (27), wherein the sensitive grid (27) is arranged between the upper and lower resin substrates (26).

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