Test system and method for measuring adhesion characteristics of cutter-soil interface

Abstract

The invention relates to a test system and method for measuring the adhesion characteristic of a cutter-soil interface, and the structure of the test system for measuring the adhesion characteristic of the cutter-soil interface comprises a cabinet which is used for accommodating a rotary loading mechanism and a data collection assembly; the adhesive force testing mechanism comprises a soil tank arranged on the cabinet, a cutter in contact with a soil sample in the soil tank, a cutter holder connected with the cutter and a transmission shaft connected with the cutter holder; the rotary loading mechanism comprises a loading mechanism and a rotating mechanism arranged on the loading mechanism, and the rotating mechanism is connected with the transmission shaft; and the data acquisition assembly comprises a load-torque sensor and a displacement sensor which are arranged on the rotary loading mechanism. According to the invention, the tool is subjected to downward pressure while rotating, and the complex movement condition and stress state of the tool in actual operation are truly simulated, so that the adhesion characteristic of the tool-soil interface is evaluated more accurately.

Description

TECHNICAL FIELD

[0001] The present application relates to an experimental device, in particular to a test system and method for measuring the adhesion characteristics of a cutter-soil interface. BACKGROUND

[0002] With the vigorous development of infrastructure, key mechanical equipment such as shield machines and dredgers play an indispensable role in underground pipe network construction and hydraulic reclamation land reclamation projects. However, when these devices pass through water-rich and viscous strata, the wet clay soil cut by the cutter is easily attached to the surface of the mechanical earth-contacting part, forming a "mud cake". Similarly, in the field of agriculture, tillage cutters also face the problem of soil adhesion. This adhesion phenomenon not only significantly reduces the working quality and efficiency of the working machine, but also increases energy consumption. In the fields of agriculture and engineering technology, especially in tunneling, port dredging, geological drilling and other practical applications involving the interaction between cutters and soil, it is necessary to study the adhesion characteristics of the soil at the interface between the cutter and the soil.

[0003] At present, although there are some test systems on the market for measuring the adhesion force of the cutter-soil interface, these systems often have limitations. For example, in actual shield cutter work, the movement is relatively complex, and the cutter is not only rotating but also subjected to forward pressure. The pulling speed and pressure size of the current experimental device are relatively single, and cannot accurately simulate the complex movement and stress state of the shield cutter in actual operation. There is a big difference between this complex movement mode and the existing test device, which seriously affects the reliability and effectiveness of the measurement data. SUMMARY

[0004] The purpose of the present application is to provide a test system and method for measuring the adhesion characteristics of a cutter-soil interface to solve the problem that the existing experimental device cannot accurately evaluate the adhesion characteristics of the cutter-soil interface.

[0005] The present application is implemented as follows: a test system for measuring the adhesion characteristics of a cutter-soil interface, which structure comprises a cabinet for accommodating a rotating loading mechanism and a data acquisition assembly; an adhesion force testing mechanism comprising a soil tank arranged on the cabinet, a cutter in contact with the soil sample in the soil tank, a cutter seat in contact with the cutter, and a transmission shaft in contact with the cutter seat; a rotating loading mechanism comprising a loading mechanism and a rotating mechanism arranged on the loading mechanism; a data acquisition assembly comprising a load-torque sensor and a displacement sensor arranged on the rotating loading mechanism.

[0006] Further, the loading mechanism comprises a telescopic driving element, a base is arranged on the telescopic driving element, a guide rod is arranged on the base, and the upper end of the guide rod is in contact with the inner top of the cabinet.

[0007] Further, the rotating mechanism comprises a connecting plate connected to the telescopic driving element, a rotating actuator connected to the lower end of the connecting plate, and an output shaft of the rotating actuator connected to the transmission shaft, and a guide sleeve matched with the guide rod is arranged on the connecting plate.

[0008] Further, the control console is used to collect and save the data generated by the data collection assembly, and issue working instructions to each component.

[0009] Further, the pneumatic driving system comprises a gas pump, a solenoid valve connected to the gas pump through a gas pipe, and a proportional directional control valve connected to the solenoid valve through a gas pipe, and the proportional directional control valve is connected to the rotating actuator and the telescopic driving element through a gas pipe.

[0010] Further, the soil groove is an annular groove body, and a through hole is arranged in the center part, and a through hole corresponding to the through hole is arranged on the cabinet, and the transmission shaft is arranged in the through holes of the soil groove and the cabinet.

[0011] A test method for measuring the adhesion characteristics of the tool-soil interface, the method comprising the following steps:

[0012] S1, system setting: setting the test system for measuring the adhesion characteristics of the tool-soil interface according to any one of claims 1-4;

[0013] S2, soil sample preparation: the telescopic driving element is actuated to raise the tool holder, then the tool holder and the soil groove are removed, the soil sample required for the experiment is placed in the soil groove, and the soil groove containing the soil sample is installed on the cabinet;

[0014] S3, tool installation: the tool is installed on the tool holder, and the tool holder containing the tool is installed on the top of the rotating shaft;

[0015] S4, tool-soil contact: the telescopic driving element is actuated to lower the tool, and the tool contacts the soil sample in the soil groove;

[0016] S5, tool rotation: the rotating actuator is actuated to rotate the tool through the transmission shaft by a predetermined angle required for the experiment;

[0017] S6, data recording and saving: saving the data recorded by the load-torque sensor and the displacement sensor;

[0018] S7, tool-soil separation and cleaning: the telescopic driving element is actuated to separate the tool from the sample, the bottom surface of the tool in contact with the sample is cleaned, and the surface of the sample is flattened;

[0019] S8, multi-factor test: repeating steps S2-S7 to perform tests under different factor conditions;

[0020] S9, information processing and analysis: the console processes the collected information, calculates the normal stress, tangential force and shear stress of the tool-soil interface;

[0021] S10, chart drawing: according to the calculation results, the failure envelope diagram is drawn.

[0022] Further, during the tool rotation in step S5, the telescopic driving element drives the tool to apply a load to the soil sample.

[0023] Further, the calculation formula of the normal stress, tangential force and shear stress of the tool-soil interface is respectively:

[0024] The normal stress formula between the tool and the soil sample is:

[0025]

[0026] Wherein, σ is the normal stress between the tool 7 and the soil sample, F n is the vertical pressure applied by the tool to the soil sample, A0 is the area of one tool 7;

[0027] The tangential force formula between the tool and the soil sample is:

[0028]

[0029] Wherein, F t is the tangential force between the tool 7 and the soil sample, d is the distance between the centers of the two blades, and M is the torque;

[0030] The shear stress formula between the tool and the soil sample is:

[0031]

[0032] Wherein, τ is the shear stress between the tool 7 and the soil sample, F t is the tangential force between the tool 7 and the soil sample, and A0 is the area of one tool 7.

[0033] Further, in the failure envelope diagram, the normal stress σ is the horizontal axis, the shear stress τ is the vertical axis, and the intercept of the tangent with the vertical axis is the adhesion C a , the slope of the tangent is the friction coefficient, is the external friction angle of the tool and the soil; the relationship formula between the shear stress, adhesion, normal stress and friction angle is:

[0034]

[0035] Wherein, τ is the shear stress between the tool 7 and the soil sample, C a is the adhesion, σ is the normal stress between the tool 7 and the soil sample, is the external friction angle of the tool and the soil.

[0036] The present application can realize the downward pressure of the cutter while rotating through the cooperation of the rotary actuator and the telescopic driving element, truly simulate the complex motion and stress state of the cutter in actual work, so as to more accurately evaluate the adhesion characteristics of the cutter-soil interface. The present application can realize the accurate control of the load applied to or removed from the cutter and the rotation angle control of the cutter through the precise control of the telescopic driving element and the rotary actuator by the console, thereby improving the accuracy and repeatability of the test. The present application installs the soil tank on the cabinet, so that the workers can intuitively observe the cutting process, facilitate the adjustment of the experiment to meet the experimental requirements, and facilitate the replacement of the soil sample and the installation of the cutter. The present application collects data in real time through the load-torque sensor and the displacement sensor, collects and processes these data through the console, calculates the normal stress, tangential force and shear stress of the cutter-soil interface, and provides quantitative analysis results for research. The present application can intuitively display the adhesion force and friction coefficient of the cutter-soil interface by drawing the soil failure envelope diagram, thereby providing intuitive reference for engineering design and optimization. The present application can optimize the interaction between the cutter and the soil by precisely controlling the test parameters and process, thereby reducing unnecessary energy consumption and cost, and providing beneficial guidance for engineering and agricultural practice. BRIEF DESCRIPTION OF DRAWINGS

[0037] Figure 1 is a structural schematic diagram of the present application.

[0038] Figure 2 is a structural schematic diagram of the internal structure of the cabinet.

[0039] Figure 3 is a structural schematic diagram of the adhesion force test mechanism.

[0040] Figure 4 is a structural schematic diagram of the cutter of Figure 3 when the cutter is raised.

[0041] Figure 5 is a structural schematic diagram of the cutter of Figure 3 when the cutter is lowered.

[0042] Figure 6 is a top view structural schematic diagram of Figure 3 .

[0043] Figure 7 is a structural schematic diagram of the electromagnetic valve and the proportional directional control valve.

[0044] Figure 8 is a soil failure envelope diagram.

[0045] In the figure: 1, cabinet, 2, transmission shaft, 3, soil tank, 4, bottom base plate, 5, bottom panel, 6, tool holder, 7, tool, 8, rotary actuator, 9, load-torque sensor, 10, connecting plate, 11, telescopic drive element, 12, base, 13, guide rod, 14, guide sleeve, 15, displacement sensor, 16, connecting shaft, 17, air pump, 18, electromagnetic valve, 19, proportional directional control valve, 20, control console. DETAILED DESCRIPTION

[0046] As shown in Figure 1 and Figure 2 , the tool-soil interface adhesion property test system includes a cabinet 1, an adhesion force test mechanism, a rotary loading mechanism, and a data acquisition assembly. The adhesion force test mechanism is arranged on the cabinet 1, and the rotary loading mechanism is arranged in the cabinet 1.

[0047] The cabinet 1 is the shell and support structure of the experimental system, which provides a stable environment to protect the internal equipment and ensures the normal operation of the system. The rotary loading mechanism and the data acquisition assembly are built-in in the cabinet 1 to prevent external interference and influence, such as preventing water, gas, dust, and other external pollutants from entering.

[0048] As shown in Figures 3-6 , the adhesion force test mechanism includes a soil tank 3 arranged on the cabinet 1 for containing soil samples, a tool 7 in contact with the soil samples in the soil tank 3, a tool holder 6 connected to the tool 7, and a transmission shaft 2 connected to the tool holder 6. During the experiment, the tool 7 extends into the soil tank 3 and contacts the soil samples in the soil tank 3. The tool 7 has a flat bottom surface for contacting the surface of the soil samples in the soil tank 3, and the width of the bottom surface of the tool 7 is smaller than the width of the soil tank 3 to prevent friction or support between the tool and the edge of the soil tank, ensuring that the tool only receives the adhesion force generated by the contact surface with the soil samples and reducing the influence of other factors.

[0049] The rotary loading mechanism includes a loading mechanism and a rotary mechanism arranged on the loading mechanism, and the rotary mechanism is connected to the transmission shaft 2.

[0050] The loading mechanism includes a telescopic drive element 11, a base 12 arranged on the telescopic drive element 11, and a guide rod 13 arranged on the base 12, with the upper end of the guide rod 13 connected to the inner top of the cabinet 1.

[0051] The rotary mechanism includes a connecting plate 10 connected to the telescopic drive element 11, a rotary actuator 8 connected to the lower end of the connecting plate 10, and an output shaft of the rotary actuator 8 connected to the transmission shaft 2. A guide sleeve 14 is arranged on the connecting plate 10 to cooperate with the guide rod 13. The guide sleeve 14 allows the connecting plate 10 to move up and down along the guide rod 13 under the drive of the telescopic drive element 11, thereby realizing the up and down movement of the tool 7 and the loading or unloading of the tool 7 on the soil samples.

[0052] The telescopic driving elements 11 are connected to the lower end of the base 12, and the piston rods of the telescopic driving elements 11 pass through the base 12 and are connected to the lower end of the connecting plate 10. The telescopic driving elements 11 are two and are symmetrically arranged on the front and rear sides of the base 12. The rotary actuator 8 is connected to the lower end of the connecting seat 10, and the output shaft of the rotary actuator 8 passes through the connecting seat 10 and is connected to the transmission shaft 2.

[0053] The data acquisition assembly includes a load-torque sensor 9 and a displacement sensor 15 arranged on the rotary loading mechanism. Specifically, the load-torque sensor 9 is arranged between the rotary actuator 8 and the transmission shaft 2, one end of the load-torque sensor 9 is connected to the output shaft of the rotary actuator 8, and the other end is connected to the transmission shaft 2. The displacement sensor 15 is connected to the base plate 12, and cooperates with the telescopic driving element 11 to detect the displacement change of the cutter 7 in the process of applying load in real time.

[0054] The tool-soil interface adhesion characteristic test system further includes a control console 20 for collecting and saving the data generated by the load-torque sensor 9 and the displacement sensor 15, and issuing work instructions to each component according to the test requirements. The rotary actuator 8 and the telescopic driving element 11 can also be controlled through the control console 20. Through the displacement data received by the control console 20, the telescopic distance of the piston rod of the telescopic driving element 11 can be accurately controlled, so as to accurately control the application or removal of load to the cutter 7.

[0055] A bottom panel 5 is arranged on the cabinet 1, and a bottom base plate 4 is arranged on the bottom panel 5. The soil tank 3 is arranged on the bottom base plate 4. The bottom base plate 4 is used to install the soil tank 3, and the bottom panel 5 is used to support the bottom base plate 4 and the soil tank 3 arranged thereon. A flange is connected to the soil tank 3, and a threaded hole corresponding to the flange is arranged on the bottom base plate 4. A standard part is used to fix the soil tank 3 to the bottom base plate 4 through the flange.

[0056] The soil tank 3 is an annular tank body with a central part being hollow to form a through hole. Corresponding through holes are formed in the bottom base plate 4, the bottom panel 5, and the cabinet 1, and the transmission shaft 2 passes through the through holes. A connecting shaft 16 is connected to the lower end of the transmission shaft 2, and the connecting shaft 16 is connected to the load-torque sensor 9. The soil tank 3 is arranged above, and the rotary actuator 8 and the telescopic driving element 11 and other key components are arranged in the cabinet 1, which is convenient for the operator to operate, maintain and replace the soil sample. At the same time, the cabinet 1 can protect the key components in the cabinet from being contaminated by the soil sample. It is also convenient for the operator to more directly observe the cutting process and adjust it to meet the experimental requirements.

[0057] The upper end of the transmission shaft 2 protrudes from the soil tank 3, the cutter holder 6 is connected to the upper end of the transmission shaft 2, the cutter holder 6 has a downwardly extending connecting portion, the cutter 7 is connected to the lower end of the connecting portion, and the connecting portion has two portions symmetrically arranged on both sides of the transmission shaft 2. In this embodiment, the cutter holder 6 is connected to the transmission shaft 2 by a standard part, and the cutter holder 6 can also be connected by splines, claws, etc.

[0058] The telescopic drive elements 11 are two, and the piston rods of the two telescopic drive elements 11 are arranged on the front and rear sides of the rotary actuator 8, respectively, and the two telescopic drive elements 11 act synchronously to ensure smooth movement of the connecting plate 10 and uniform application of load.

[0059] As shown in Figure 7 The rotary actuator 8 and the telescopic drive element 11 in this embodiment are both driven by gas. The application also includes a pneumatic drive system, which includes a gas pump 17, a solenoid valve 18, and a proportional directional control valve 19. The gas pump 17 is connected to the solenoid valve 18 through a gas pipe, the solenoid valve 18 is connected to the proportional directional control valve 19 through a gas pipe, and the solenoid valve 18 and the proportional directional control valve 19 are arranged on the inner wall of the cabinet 1. The gas outlet of the proportional directional control valve 19 has two portions, which are connected to the rotary actuator 8 and the telescopic drive element 11 through gas pipes, respectively. The proportional directional control valve 19 can provide stable and controllable gas sources for the rotary actuator 8 and the telescopic drive element 11 as needed, so as to ensure that they can work in a predetermined manner to achieve precise control of the rotation angle of the rotary actuator 8 and the telescopic distance of the piston rod of the telescopic drive element 11. The rotary actuator 8 in this embodiment can also be a hydraulic rotary actuator, a motor rotary actuator, etc.; the telescopic drive element 11 can also be an electric push rod, a gas cylinder, a hydraulic push rod, etc.

[0060] Wheels are also arranged at the lower part of the cabinet 1, and the entire test system can be easily moved between the laboratory or different working areas, improving the flexibility and portability of the system.

[0061] The test method for measuring the adhesion properties of the cutter-soil interface is as follows:

[0062] S1, system setting: set the test system for measuring the adhesion properties of the cutter-soil interface as described above;

[0063] S2, soil sample preparation: start the gas pump 17 and the console 20; the telescopic drive element 11 acts to raise the cutter holder 6, then the cutter holder 6 and the soil tank 3 are removed, the soil sample required for the experiment is placed in the soil tank 3, and the surface of the soil sample is ensured to be flat, then the soil tank 3 containing the soil sample is installed on the cabinet 1, and the surface of the soil sample is ensured to be flat;

[0064] S3, cutter installation: install the cutter 7 on the cutter holder 6, and install the cutter holder 6 containing the cutter 7 on the top of the transmission shaft;

[0065] S4, Cutter-soil contact: The telescopic drive element 11 is activated, causing the cutter 7 to descend, and the lower surface of the cutter 7 contacts the upper surface of the soil sample in the soil trough 3.

[0066] S5. Cutter Rotation: The rotary actuator 8 actuates, driving the cutter 7 to rotate via the transmission shaft 2. The control console 20 controls the rotary actuator 8 to rotate by the predetermined angle required for the experiment. In this embodiment, the rotary actuator 8 drives the cutter to rotate 180°. During the rotation of the cutter 7, the control console 20 guides the downward movement of the cutter 7 by controlling the telescopic drive element 11 to apply the predetermined load required for the experiment to the soil sample, so as to realistically simulate the stress situation of the shield cutter during operation.

[0067] S6. Data recording and storage: Store the data recorded by the load-torque sensor 9 during the test process;

[0068] S7. Cutter-soil separation and cleaning: The telescopic drive element 11 is activated to separate the cutter 7 from the soil sample, clean the bottom surface of the cutter in contact with the soil sample, and flatten the surface of the soil sample.

[0069] S8. Multi-factor test: Repeat steps S2-S7 and conduct tests under different factor conditions. In this step, apply different vertical pressures to the soil sample with the cutter 7, and use different sliding speeds of the cutter 7, different soil moisture contents, cutters of different materials, and cutter surfaces with different roughness.

[0070] S9. Information Processing and Analysis: The console 20 processes the collected information; it calculates the normal stress, tangential force, and shear stress at the cutter-soil interface.

[0071] S10. Chart Drawing: Based on the calculation results, draw the following charts: Figure 8 The diagram shows the failure envelope of the soil. In the diagram, the normal stress σ is on the horizontal axis, the shear stress τ is on the vertical axis, and the intercept of the tangent line with the vertical axis is the adhesion force C. a The slope of the tangent is the coefficient of friction. The external friction angle between the cutting tool 7 and the soil sample is denoted as 7.

[0072] The formula relating shear stress, adhesive force, normal stress, and friction angle is:

[0073]

[0074] Where τ is the shear stress between the tool 7 and the soil sample, and C a The adhesive force is σ, which is the normal stress between the tool 7 and the soil sample. The external friction angle between the cutting tool 7 and the soil sample is denoted as 7.

[0075] The normal stress between the cutting tool 7 and the soil sample is expressed by the following formula:

[0076]

[0077] where σ is the normal stress between the tool 7 and the soil sample, F n is the vertical pressure applied by the tool to the soil sample, and A0 is the area of one tool 7.

[0078] The tangential force between the tool 7 and the soil sample is expressed by the following formula:

[0079]

[0080] where F t is the tangential force between the tool 7 and the soil sample, and d is the distance between the centers of the two blades,

[0081] M is the torque;

[0082] The shear stress between the tool 7 and the soil sample is expressed by the following formula:

[0083]

[0084] where τ is the shear stress between the tool 7 and the soil sample, F t is the tangential force between the tool 7 and the soil sample, and A0 is the area of one tool 7.

[0085] Through the six sets of normal stress and shear stress data, the soil failure envelope diagram can be obtained, in which the intercept C a of the tangent line with the vertical axis is the adhesion force, and the slope of the tangent line is the friction coefficient, is the soil-tool friction angle.

Claims

1. A test system for measuring the adhesion properties of a tool-soil interface, characterized by, The device comprises a cabinet for accommodating a rotary loading mechanism and a data acquisition assembly; a sticking force testing mechanism comprising a soil groove arranged on the cabinet, a cutter in contact with a soil sample in the soil groove, a cutter seat in contact with the cutter, and a transmission shaft in contact with the cutter seat; the rotary loading mechanism comprises a loading mechanism and a rotary mechanism arranged on the loading mechanism, and the rotary mechanism is in contact with the transmission shaft; the data acquisition assembly comprises a load-torque sensor and a displacement sensor arranged on the rotary loading mechanism.

2. The test system for measuring the adhesion properties of a tool-soil interface according to claim 1, wherein, The loading mechanism comprises a telescopic driving element, a base arranged on the telescopic driving element, and a guide rod arranged on the base, and the upper end of the guide rod is in contact with the inner top of the cabinet.

3. The test system for measuring the adhesion properties of a tool-soil interface according to claim 2, wherein, The rotary mechanism comprises a connecting plate connected to the telescopic driving element, a rotary actuator connected to the lower end of the connecting plate, and an output shaft of the rotary actuator is in contact with the transmission shaft, and a guide sleeve cooperating with the guide rod is arranged on the connecting plate.

4. The test system for measuring the adhesion properties of a tool-soil interface of claim 1, wherein, The device further comprises a control console for collecting and saving data generated by the data acquisition assembly and issuing work instructions to each component.

5. The test system for measuring the adhesion properties of a tool-soil interface according to claim 3, wherein, The device further comprises a pneumatic driving system comprising a gas pump, a solenoid valve connected to the gas pump through a gas conveying pipe, and a proportional directional control valve connected to the solenoid valve through a gas conveying pipe, and the proportional directional control valve is connected to the rotary actuator and the telescopic driving element through a gas conveying pipe.

6. The test system for measuring the adhesion properties of a tool-soil interface of claim 1, wherein, The soil groove is an annular groove body, and the central part is a through hole, and a through hole corresponding to the through hole is formed on the cabinet, and the transmission shaft is arranged in the through holes of the soil groove and the cabinet.

7. A test method for measuring the adhesion properties of a tool-soil interface, characterized by, The device comprises the following steps: S1, system setting: setting a test system for measuring the sticking characteristics of the cutter-soil interface according to any one of claims 1-4; S2, soil sample preparation: the telescopic driving element is actuated to raise the cutter seat, then the cutter seat and the soil groove are removed, the soil sample required for the experiment is placed in the soil groove, and the soil groove containing the soil sample is installed on the cabinet; S3, cutter installation: the cutter is installed on the cutter seat, and the cutter seat with the cutter is installed on the top of the rotary shaft; S4, cutter-soil contact: the telescopic driving element is actuated to lower the cutter, and the cutter is in contact with the soil sample in the soil groove; S5, cutter rotation: the rotary actuator is actuated to rotate the cutter through the transmission shaft by a predetermined angle required for the experiment; S6, data recording and saving: saving the data recorded by the load-torque sensor and the displacement sensor; S7, cutter-soil separation and cleaning: the telescopic driving element is actuated to separate the cutter from the soil sample, the bottom surface of the cutter in contact with the soil sample is cleaned, and the surface of the soil sample is flattened; S8, multi-factor testing: repeating steps S2-S7 to perform experiments under different factor conditions; S9, information processing and analysis: the collected information is processed by the control console to calculate the normal stress, tangential force and shear stress of the cutter-soil interface; S10, chart drawing: according to the calculation results, a failure envelope diagram is drawn.

8. The test method of measuring the adhesion properties of a tool-soil interface according to claim 7, wherein, During the cutter rotation in step S5, the telescopic driving element applies a load to the cutter towards the soil sample.

9. The test method of measuring the adhesion properties of a tool-soil interface according to claim 7, wherein, The calculation formulas of the normal stress, tangential force and shear stress of the cutter-soil interface are respectively: The formula of the normal stress between the cutter and the soil sample is: Wherein, σ is the normal stress between the cutter 7 and the soil sample, F n is the vertical pressure applied by the cutter to the soil sample, A0 is the area of one cutter 7; The formula of the tangential force between the cutter and the soil sample is: The formula of the shear stress between the cutter and the soil sample is: where F t is the tangential force between the tool 7 and the soil sample, d is the distance between the centers of the two blades, and M is the torque. The formula of the shear stress between the tool and the pattern is: where τ is the shear stress between the tool 7 and the soil sample, F t is the tangential force between the tool 7 and the soil sample, and A0is the area of one tool 7.

10. The test method of measuring the adhesion properties of a tool-soil interface according to claim 7, wherein, In the damage envelope diagram, the normal stress σ is the horizontal axis, the shear stress τ is the vertical axis, and the intercept of the tangent line with the vertical axis is the adhesion C a The slope of the tangent line is the friction coefficient, The external friction angle of the tool and the soil sample; the relationship formula among the shear stress, the adhesion, the normal stress, and the friction angle is: where τ is the shear stress between the tool 7 and the soil sample, C a is the adhesion force, σ is the normal stress between the tool 7 and the soil sample, is the external friction angle between the tool 7 and the soil sample.

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