A low-disturbance sample loading auxiliary device for micro-soil triaxial test

Abstract

This utility model relates to the technical field of indoor geotechnical testing instruments and equipment, specifically to a low-disturbance sample loading auxiliary device for micro soil triaxial testing. It includes a fixed base, a split-film forming mechanism, and a negative pressure pushing sleeve mechanism. The top of the fixed base is independently equipped with a vertical threaded screw and a triaxial apparatus metal base. The split-film forming mechanism is detachably mounted on the triaxial apparatus metal base. The negative pressure pushing sleeve mechanism can move smoothly along the axial direction, relying on negative pressure adsorption to fix the sample cap. No manual alignment is required throughout the process, effectively avoiding eccentricity and tilting of the micro-sample, significantly reducing local stress concentration, preventing premature damage, and ensuring test accuracy. The device integrates membrane negative pressure adsorption and O-ring sealing and limiting structures, eliminating the need for tools to press the sample against the mounting components, eliminating the damage to the soil sample structure caused by impact and friction, preventing soil structure collapse and remodeling, and improving the reliability of mechanical parameter test results.

Description

Technical Field

[0001] This utility model relates to the technical field of indoor geotechnical testing instruments and equipment, specifically to a low-disturbance sample loading auxiliary device for micro soil triaxial testing. Background Technology

[0002] The triaxial compression test is the most fundamental and important laboratory test method for determining the shear strength parameters and stress-strain relationship of soil. Traditional triaxial tests typically use relatively large specimens with a diameter of 39.1 mm or 50 mm. However, with the development of modern geotechnical mechanics towards the microscopic level, especially when studying particle movement and pore evolution within soil using non-destructive testing techniques, the size of the specimen often needs to be reduced to 20 mm in diameter and 40 mm in height, or even smaller, due to limitations in the penetration and resolution requirements of scanning equipment.

[0003] The significant reduction in sample size makes it extremely sensitive to boundary disturbances. In the conventional sample loading process, testers often use a purely manual method to place the soil sample, put on the top cap, and install the sealing O-ring.

[0004] For a standard specimen with a diameter of 50 mm, slight hand tremors and pressure are generally within an acceptable error range; however, for a tiny specimen with a diameter of only 20 mm, manually placing the top cap can easily cause eccentricity and tilting, thereby inducing local stress concentration and premature failure of the specimen.

[0005] In addition, when using traditional rubber membrane stretchers and O-ring installation tools, the tool edges often need to be pressed against the sample surface to apply force, resulting in instantaneous longitudinal impact or surface friction. This can easily cause the fragile microstructure of the soil sample to collapse or reshape, resulting in distortion of the final measured mechanical parameters.

[0006] In conclusion, designing a specialized sample loading auxiliary device for small soil samples that can achieve mechanical centering, negative pressure isolation, and non-destructive sealing, in order to minimize the disturbance to the soil during the assembly process, has significant engineering and scientific research value. Utility Model Content

[0007] To achieve the above objectives, this utility model adopts the following technical solution: This utility model provides a low-disturbance sample loading auxiliary device for micro soil triaxial testing. The negative pressure pushing sleeve mechanism can move smoothly along the axial direction, relying on negative pressure adsorption to fix the top cap of the sample. There is no manual alignment operation throughout the process, which effectively avoids the problem of eccentricity and tilting of micro samples, helps to reduce local stress concentration of the sample, avoids premature damage, and helps to ensure the accuracy of the test. The device integrates membrane negative pressure adsorption and O-ring sealing and limiting structure, eliminating the need for tools to press the sample and install the components, eliminating the damage to the soil sample structure caused by impact and friction, preventing the soil structure from collapsing and reshaping, and improving the reliability of mechanical parameter test results.

[0008] To address the problems of existing technologies, this utility model provides a low-disturbance sample loading auxiliary device for micro soil triaxial tests, including a fixed base, a split film-forming mechanism, and a negative pressure pushing sleeve mechanism. The top of the fixed base is independently equipped with a vertical threaded screw and a triaxial apparatus metal base. The bottom end of the vertical threaded screw is rotatably connected to the fixed base, and the top end of the vertical threaded screw is fixedly fitted with a manual fine-tuning handwheel. The split film-forming mechanism is detachably mounted on the triaxial apparatus metal base. The split film-forming mechanism includes a split film-bearing cylinder and a sealing clamp. The split film-bearing cylinder is formed by the joining of two semi-cylindrical outer shells. After the two outer shells are locked and positioned by the sealing clamp, they form a complete cylindrical cavity coaxially arranged with the triaxial apparatus metal base. It also includes a negative pressure adsorption channel for negative pressure adsorption and fixation of the membrane laid inside the split-type film-forming cylinder; the negative pressure pushing sleeve mechanism is located directly above the split-type film-forming mechanism and can move along the axial direction of the split-type film-forming mechanism; the negative pressure pushing sleeve mechanism has a receiving cavity with a through lower end inside, and a sample cap is fixed to the top of the receiving cavity by negative pressure adsorption; a sealing O-ring is fitted on the outer side of the negative pressure pushing sleeve mechanism, and an annular groove is formed inward on the outer wall of the sample cap, which is used to seal and limit the top of the membrane after the sample is loaded, in conjunction with the sealing O-ring; the outer diameter of the negative pressure pushing sleeve mechanism is adapted to the inner diameter of the split-type film-forming cylinder; a lifting cantilever is connected to the top of the negative pressure pushing sleeve mechanism, and the lifting cantilever is threadedly driven by a vertical threaded screw.

[0009] Preferably, a guide rod is also vertically provided on the fixed base, and the guide rod provides vertical guidance for the lifting cantilever.

[0010] Preferably, the split-type film-bearing cylinder has a hollow adsorption cavity coaxially arranged inside, and the inner wall of the split-type film-bearing cylinder has a plurality of capillary through holes communicating with the hollow adsorption cavity; a negative pressure suction connector is fixedly installed on the outer side of the split-type film-bearing cylinder, and the negative pressure suction connector is connected to the hollow adsorption cavity; the hollow adsorption cavity, the capillary through holes and the negative pressure suction connector together constitute the negative pressure adsorption channel.

[0011] Preferably, the negative pressure pusher sleeve mechanism includes a thin-walled pusher sleeve, a vacuum suction nozzle disk is detachably installed at the top of the thin-walled pusher sleeve, and the sample top cap is arranged inside the thin-walled pusher sleeve; a negative pressure suction pipe is provided at the top of the vacuum suction nozzle disk, and the lifting arm is fixedly connected to the vacuum suction nozzle disk.

[0012] Preferably, the lower outer wall of the thin-walled pusher sleeve is provided with a pre-installation groove, which is used for temporary assembly of sealing O-rings; the thin-walled pusher sleeve and the vacuum nozzle disc adopt a detachable connection structure.

[0013] Preferably, the thin-walled pusher sleeve is made of polytetrafluoroethylene.

[0014] Preferably, the inner diameters of the split-type membrane-bearing cylinder and the thin-walled pusher sleeve are 20mm, 39.1mm, and 50mm, respectively, to accommodate standard soil samples of different specifications.

[0015] Preferably, the bottom of the split film-bearing cylinder extends downward with a positioning block, and the top of the triaxial instrument metal base is provided with a positioning groove that matches the positioning block. The positioning block and the positioning groove cooperate to realize the positioning and installation of the split film-bearing cylinder.

[0016] The advantages of this utility model compared to the prior art are:

[0017] 1. The negative pressure pusher sleeve mechanism can move smoothly along the axis and fix the sample cap by negative pressure adsorption. There is no manual alignment operation throughout the process, which effectively avoids the problem of eccentricity and tilting of small samples. It helps to reduce local stress concentration of the sample, avoid premature failure, and help ensure the accuracy of the test.

[0018] 2. The device integrates membrane negative pressure adsorption and O-ring sealing and limiting structure, eliminating the need for tools to press the sample against the mounting components, thus eliminating the damage to the soil sample structure caused by impact and friction, preventing the soil structure from collapsing and reshaping, and improving the reliability of mechanical parameter test results. Attached Figure Description

[0019] Figure 1 This is a three-dimensional structural diagram of a low-disturbance sample loading auxiliary device for micro soil triaxial testing.

[0020] Figure 2 This is a side-view three-dimensional cross-sectional diagram of a low-disturbance sample loading auxiliary device used for micro soil triaxial tests.

[0021] Figure 3 yes Figure 2 A magnified structural diagram at point A.

[0022] Figure 4 yes Figure 2 A magnified structural diagram at point B.

[0023] Figure 5 This is a schematic diagram of the main view section of a low-disturbance sample loading auxiliary device used for micro soil triaxial tests.

[0024] Figure 6 This is a schematic diagram of the disassembled structure of a low-disturbance sample loading auxiliary device for micro soil triaxial testing.

[0025] The following are the labels in the diagram: 1. Fixed base; 1a. Vertical threaded screw; 1a1. Manual fine-tuning handwheel; 1b. Triaxial apparatus metal base; 1c. Guide rod; 2. Split film-forming mechanism; 2a. Split film-bearing cylinder; 2a1. Hollow adsorption chamber; 2a2. Negative pressure suction connector; 2a3. Positioning block; 2b. Sealing clamp; 2c. Negative pressure adsorption channel; 3. Negative pressure pushing sleeve mechanism; 3a. Lifting cantilever; 3b. Sealing O-ring; 3c. Thin-walled pushing sleeve; 3c1. Vacuum suction nozzle plate; 4. Sample top cap. Detailed Implementation

[0026] To further understand the features, technical means, and specific objectives and functions achieved by this utility model, the following detailed description of this utility model is provided in conjunction with the accompanying drawings and specific embodiments.

[0027] See Figure 1 As shown, a low-disturbance sample loading auxiliary device for micro soil triaxial testing includes a fixed base 1, a split film forming mechanism 2, and a negative pressure pushing sleeve mechanism 3. The top of the fixed base 1 is independently provided with a vertical threaded screw 1a and a triaxial instrument metal base 1b.

[0028] The bottom end of the vertical threaded screw 1a is rotatably connected to the fixed base 1, and the top end of the vertical threaded screw 1a is fixedly equipped with a manual fine-tuning handwheel 1a1.

[0029] The aforementioned vertical threaded lead screw 1a and the triaxial instrument metal base 1b are arranged independently on the top surface of the fixed base 1, and do not interfere with each other's installation and movement.

[0030] The operator can rotate the manual fine-tuning handwheel 1a1 at the top to drive the vertical threaded screw 1a to rotate, providing power for the subsequent lifting and adjustment of the mechanism.

[0031] See Figure 2 , Figures 4 to 6 As shown, the split film-forming mechanism 2 is detachably installed on the metal base 1b of the triaxial apparatus. The split film-forming mechanism 2 includes a split film-bearing cylinder 2a and a sealing clamp 2b. The split film-bearing cylinder 2a is composed of two semi-cylindrical outer shells joined together.

[0032] After the two outer shells are locked and positioned by the sealing clamp 2b, they form a complete cylindrical cavity coaxial with the metal base 1b of the triaxial instrument.

[0033] Among them, the split film forming mechanism 2 serves as the load-bearing structure for laying the test film and forming the sample. It can be disassembled as a whole, which facilitates cleaning and assembly before and after the test.

[0034] The sealing clamp 2b can be an elastic hoop. The two semi-cylindrical outer shells can be tightened and fixed by the sealing clamp 2b, and can be spliced ​​to form a regular cylindrical cavity. The cavity and the metal base 1b of the triaxial instrument below maintain coaxiality, ensuring that there is no eccentric foundation error during the sample loading process.

[0035] See Figure 2 , Figures 3 to 6 As shown, the split film-forming mechanism 2 is also provided with a negative pressure adsorption channel 2c, which is used for negative pressure adsorption to fix the film laid inside the split film-bearing cylinder 2a.

[0036] The split film-forming mechanism 2 is equipped with a negative pressure adsorption channel 2c. During operation, the negative pressure suction can tightly adhere and fix the membrane required for the test to the inner wall of the split film-bearing cylinder 2a, replacing the traditional method of manually opening and fixing the membrane. This avoids manual operation that touches or squeezes the membrane and the sample, thus reducing soil disturbance from the source.

[0037] See Figure 1 and Figure 2 As shown, the negative pressure pushing sleeve mechanism 3 is located directly above the split film forming mechanism 2 and can move along the axial direction of the split film forming mechanism 2. The negative pressure pushing sleeve mechanism 3 has a receiving cavity with a through lower end inside, and the sample top cap 4 is fixed to the top of the receiving cavity by negative pressure adsorption.

[0038] During operation, the negative pressure pusher sleeve mechanism 3 is positioned directly above the film forming station and can move smoothly up and down along the vertical axis to ensure that the sample feeding path remains vertically aligned without deviation.

[0039] The mechanism has a vertically connected storage space inside, and uses negative pressure adsorption to stably fix the sample cap 4 on the top of the storage cavity. There is no need for manual hand placement of the cap, which completely avoids the problems of manual alignment, shaking, offset and tilting when loading small samples.

[0040] See Figure 2 , Figure 3 , Figure 5 and Figure 6 As shown, a sealing O-ring 3b is fitted on the outer side of the negative pressure pusher sleeve mechanism 3, and an annular groove is opened inward on the outer wall of the sample top cap 4, which is used to cooperate with the sealing O-ring 3b to seal and limit the top of the membrane after the sample is loaded.

[0041] During operation, the sealing O-ring 3b is fitted outside the negative pressure pusher sleeve mechanism 3 and can be matched and inserted into the annular groove on the outer wall of the sample top cap 4 to achieve precise positioning of the two.

[0042] After the sample is loaded, the top of the membrane can be pressed, sealed and fixed by the sealing O-ring 3b to ensure the sealing effect of the top of the sample, while constraining the position of the membrane to prevent the membrane from shifting or falling off during the loading process.

[0043] See Figure 2 and Figure 5 As shown, the outer diameter of the negative pressure pushing sleeve mechanism 3 is adapted to the inner diameter of the split film-bearing cylinder 2a.

[0044] The top of the negative pressure pusher sleeve mechanism 3 is connected to a lifting cantilever 3a, which is threadedly driven by the vertical threaded screw 1a.

[0045] A guide rod 1c is also vertically arranged on the fixed base 1, and the guide rod 1c provides vertical guidance for the lifting cantilever 3a.

[0046] It should be noted that the external dimensions of the negative pressure pusher sleeve mechanism 3 and the internal dimensions of the split film-bearing cylinder 2a are matched, allowing it to smoothly enter the cylinder during movement.

[0047] The lifting arm 3a is supported above the negative pressure pushing sleeve mechanism 3 and is threadedly engaged with the vertical threaded screw 1a. When the screw rotates, it can drive the lifting arm 3a and the entire structure to rise and fall.

[0048] The guide rod 1c on the fixed base 1 is arranged vertically, which can limit the movement trajectory of the lifting arm 3a and prevent it from deviating.

[0049] See Figure 2 , Figures 3 to 6 As shown, the split-type film-bearing cylinder 2a has a hollow adsorption cavity 2a1 coaxially arranged inside, and the inner wall of the split-type film-bearing cylinder 2a has a number of capillary through holes that communicate with the hollow adsorption cavity 2a1.

[0050] A negative pressure suction connector 2a2 is fixedly installed on the outside of the split membrane-bearing cylinder 2a, and the negative pressure suction connector 2a2 is connected to the hollow adsorption cavity 2a1.

[0051] The hollow adsorption cavity 2a1, the capillary through-hole, and the negative pressure suction connector 2a2 together constitute the negative pressure adsorption channel 2c.

[0052] The hollow adsorption cavity 2a1 is set along the center direction of the split film-bearing cylinder 2a. The capillary through holes distributed on the inner wall of the cylinder are connected to the hollow adsorption cavity 2a1, and the negative pressure suction connector 2a2 installed on the outside is also connected to the hollow adsorption cavity 2a1.

[0053] During use, air is drawn from the negative pressure suction connector 2a2, and the airflow passes through the hollow adsorption chamber 2a1 and the capillary holes on the inner wall in sequence to form a negative pressure environment. The entire structure is combined to form a negative pressure adsorption channel 2c, which realizes the adsorption and fixation of the membrane.

[0054] See Figure 2 , Figure 5 and Figure 6As shown, the negative pressure pusher sleeve mechanism 3 includes a thin-walled pusher sleeve 3c, and a vacuum suction nozzle disk 3c1 is detachably installed at the top of the thin-walled pusher sleeve 3c. The sample top cap 4 is arranged inside the thin-walled pusher sleeve 3c.

[0055] The vacuum nozzle plate 3c1 is equipped with a negative pressure suction tube at its top, and the lifting arm 3a is fixedly connected to the vacuum nozzle plate 3c1.

[0056] Among them, the thin-walled pusher sleeve 3c is the main part of the negative pressure pusher sleeve mechanism 3, and its upper end is vertically connected to the end of the lifting cantilever 3a. The sample top cap 4 is placed inside the thin-walled pusher sleeve 3c.

[0057] The vacuum suction nozzle plate 3c1 is installed on the top of the thin-walled pusher sleeve 3c, which closes the top opening. At the same time, the vacuum suction nozzle plate 3c1 and the lifting cantilever 3a are fixed together. The negative pressure suction pipe above it can draw air to generate negative pressure, thereby sucking up the sample top cap 4. The vacuum suction nozzle plate 3c1 can also be disassembled separately.

[0058] See Figure 3 , Figure 5 and Figure 6 As shown, the lower outer wall of the thin-walled pusher sleeve 3c is provided with a pre-installation groove, which is used for temporary assembly of the sealing O-ring 3b.

[0059] The thin-walled pusher sleeve 3c and the vacuum nozzle plate 3c1 are connected by bolts for easy replacement.

[0060] It should be noted that the thin-walled pusher sleeve 3c has a pre-installed groove machined on the outer side of its bottom, which allows the sealing O-ring 3b to be placed in advance for convenient subsequent assembly operations.

[0061] See Figure 3 As shown, the thin-walled pusher sleeve 3c is made of polytetrafluoroethylene.

[0062] The lower end of the thin-walled pusher sleeve 3c is provided with a guide chamfer. The thin-walled pusher sleeve 3c is made of polytetrafluoroethylene, which has a low coefficient of friction and is not easy to damage the parts.

[0063] The internal diameter of the thin-walled pusher sleeve 3c is 0.5 mm larger than the external dimensions of the sample top cap 4, leaving a reasonable gap.

[0064] The lower end is equipped with a chamfered structure, which can act as a guide during downward movement, making the connection of components smoother.

[0065] See Figure 2 and Figure 6 As shown, the inner diameters of the split membrane-bearing cylinder 2a and the thin-walled pusher sleeve 3c are 20mm, 39.1mm, and 50mm, respectively, which are adapted to standard soil samples of different specifications.

[0066] The split-type film-bearing cylinder 2a and the thin-walled pusher sleeve 3c mentioned above are both independent modular accessories that can be directly replaced.

[0067] Both are available in a variety of inner diameter sizes, corresponding to the commonly used specifications of 20mm, 39.1mm and 50mm, which can meet the sample loading and testing requirements of soil samples of different sizes.

[0068] See Figure 2 and Figure 6 As shown, a positioning block 2a3 extends downward from the bottom of the split film-bearing cylinder 2a, and a positioning groove adapted to the positioning block 2a3 is opened on the top of the triaxial instrument metal base 1b. The positioning block 2a3 and the positioning groove cooperate to realize the positioning and installation of the split film-bearing cylinder 2a.

[0069] It should be added that the bottom of the split film-bearing cylinder 2a is integrally machined with a positioning block 2a3, and the top surface of the triaxial instrument metal base 1b has a corresponding positioning groove.

[0070] During installation, the positioning block 2a3 is inserted into the positioning groove to complete the alignment and fixation of the split film-bearing cylinder 2a, preventing positional displacement during operation.

[0071] In summary, when using this device, first use the sealing clamp 2b to close the split film-bearing cylinder 2a, and then align the positioning block 2a3 at the bottom of the split film-bearing cylinder 2a with the positioning groove, and then coaxially sleeve the split film-bearing cylinder 2a on the outside of the triaxial instrument metal base 1b.

[0072] A membrane body is fitted inside the split membrane-bearing cylinder 2a.

[0073] After the membrane is installed, the external negative pressure device is connected to the negative pressure suction connector 2a2, and the membrane is evenly adsorbed onto the inner wall of the split membrane support cylinder 2a through the hollow adsorption cavity 2a1 and the capillary through-hole.

[0074] A small soil sample was placed inside a split membrane-supported cylinder 2a.

[0075] Place the sample cap 4 inside the thin-walled pusher sleeve 3c, and connect the external negative pressure device to the vacuum suction plate 3c1 so that the sample cap 4 is stabilized in the inner cavity of the thin-walled pusher sleeve 3c by negative pressure adsorption.

[0076] Rotating the manual fine-tuning handwheel 1a1 drives the vertical threaded screw 1a to rotate, which in turn drives the lifting cantilever 3a, vacuum suction plate 3c1, thin-walled pusher sleeve 3c and sample top cap 4 to move down to the top of the small soil sample under the guidance of the guide rod 1c.

[0077] When the external negative pressure device is turned off and the connection between the external negative pressure device and the vacuum suction nozzle plate 3c1 is disconnected, the negative pressure disappears, and the sample cap 4 comes into close contact with the top of the tiny soil sample under the action of gravity.

[0078] Rotate the vertical threaded screw 1a to move the thin-walled pusher sleeve 3c upward to expose the annular groove of the sample top cap 4, and adjust the position of the membrane so that its top is fitted on the outside of the sample top cap 4 and the annular groove.

[0079] Push the sealing O-ring 3b at the bottom of the thin-walled pusher sleeve 3c downwards until it reaches the annular groove. At this time, the sealing O-ring 3b, under its elastic action, presses the membrane in contact with it into the annular groove, which can drive the membrane to seal and load the small soil sample.

[0080] Continue rotating the vertical threaded screw 1a to reset the thin-walled pusher sleeve 3c and the vacuum suction plate 3c1, and remove the small soil sample after sealing and loading, and then proceed to the next sealing and loading operation.

[0081] The above embodiments only illustrate one or more implementations of this utility model, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of this utility model. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the appended claims.

Claims

1. A low disturbance sample preparation aid for micro-scale soil triaxial testing, characterized in that, It includes a fixed base (1), a split film forming mechanism (2), and a negative pressure pushing sleeve mechanism (3); The top of the fixed base (1) is independently provided with a vertical threaded screw (1a) and a triaxial instrument metal base (1b); the bottom end of the vertical threaded screw (1a) is rotatably connected to the fixed base (1), and the top end of the vertical threaded screw (1a) is fixedly equipped with a manual fine-tuning handwheel (1a1). The split film-forming mechanism (2) is detachably installed on the triaxial apparatus metal base (1b). The split film-forming mechanism (2) includes a split film-bearing cylinder (2a) and a sealing clamp (2b). The split film-bearing cylinder (2a) is formed by two semi-cylindrical outer shells joined together. After the two outer shells are locked and positioned by the sealing clamp (2b), they form a complete cylindrical cavity coaxial with the triaxial apparatus metal base (1b). The split film-forming mechanism (2) is also provided with a negative pressure adsorption channel (2c) for negative pressure adsorption and fixing of the film laid inside the split film-bearing cylinder (2a). The negative pressure pusher sleeve mechanism (3) is located directly above the split film forming mechanism (2) and can move along the axial direction of the split film forming mechanism (2). The negative pressure pusher sleeve mechanism (3) has a cavity with a through lower end inside. The top of the cavity is fixed with a sample cap (4) by negative pressure adsorption. A sealing O-ring (3b) is sleeved on the outside of the negative pressure pusher sleeve mechanism (3). The outer wall of the sample cap (4) has an annular groove that is opened inward to cooperate with the sealing O-ring (3b) to seal and limit the top of the film after the sample is loaded. The outer diameter of the negative pressure pusher sleeve mechanism (3) is adapted to the inner diameter of the split film-bearing cylinder (2a). The top of the negative pressure pusher sleeve mechanism (3) is connected to a lifting cantilever (3a), which is threadedly driven by the vertical threaded screw (1a).

2. The low-disturbance sample loading auxiliary device for micro-soil triaxial testing according to claim 1, characterized in that, The split-type film-bearing cylinder (2a) has a hollow adsorption cavity (2a1) coaxially arranged inside, and the inner wall of the split-type film-bearing cylinder (2a) has a number of capillary through holes that communicate with the hollow adsorption cavity (2a1). A negative pressure suction connector (2a2) is fixedly installed on the outside of the split membrane cylinder (2a), and the negative pressure suction connector (2a2) is connected to the hollow adsorption cavity (2a1). The hollow adsorption cavity (2a1), capillary through-hole, and negative pressure suction connector (2a2) together constitute the negative pressure adsorption channel (2c).

3. The low-disturbance sample loading auxiliary device for micro-soil triaxial testing according to claim 2, characterized in that, The negative pressure pusher sleeve mechanism (3) includes a thin-walled pusher sleeve (3c), and a vacuum suction nozzle plate (3c1) is detachably installed at the top of the thin-walled pusher sleeve (3c). The sample top cap (4) is arranged inside the thin-walled pusher sleeve (3c). The vacuum nozzle plate (3c1) is equipped with a negative pressure suction tube at the top, and the lifting arm (3a) is fixedly connected to the vacuum nozzle plate (3c1).

4. The low-disturbance sample loading auxiliary device for micro-soil triaxial testing according to claim 3, characterized in that, The lower outer wall of the thin-walled pusher sleeve (3c) is provided with a pre-installation groove, which is used for temporary assembly of sealing O-rings (3b). The thin-walled pusher sleeve (3c) and the vacuum nozzle plate (3c1) adopt a detachable connection structure.

5. The low-disturbance sample loading auxiliary device for micro-soil triaxial testing according to claim 4, characterized in that, The thin-walled pusher sleeve (3c) is made of polytetrafluoroethylene.

6. The low-disturbance sample loading auxiliary device for micro-soil triaxial testing according to claim 5, characterized in that, The inner diameters of the split-type membrane-bearing cylinder (2a) and the thin-walled pusher sleeve (3c) are 20mm, 39.1mm, and 50mm, respectively, to accommodate standard soil samples of different specifications.

7. The low-disturbance sample loading auxiliary device for micro-soil triaxial testing according to claim 6, characterized in that, The bottom of the split film-bearing cylinder (2a) extends downward with a positioning block (2a3), and the top of the triaxial instrument metal base (1b) is provided with a positioning groove that matches the positioning block (2a3). The positioning block (2a3) and the positioning groove cooperate to realize the positioning and installation of the split film-bearing cylinder (2a).

8. The low-disturbance sample loading auxiliary device for micro-soil triaxial testing according to claim 1, characterized in that, A guide rod (1c) is also vertically arranged on the fixed base (1), and the guide rod (1c) provides vertical guidance for the lifting arm (3a).

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