Experimental equipment and method for measuring interface adhesion strength of soil and shield cutter head under seepage action

Abstract

The invention discloses experimental equipment and method for determining the interface adhesion strength of soil and a shield cutter head under the action of seepage, the experimental equipment comprises a soil sample negative pressure seepage device and an adhesion strength measuring device, the soil sample negative pressure seepage device comprises a support and a permeator, the support is provided with a holder and a water supply system, and the permeator is clamped on the holder. The research blank that the influence of underground water seepage on the adhesion strength is not considered in existing shield adhesion research is filled, and meanwhile the problems that existing adhesion research experiment equipment is expensive, and the operation process is complex are solved. According to the invention, the adhesion strength between different types of viscous soil and the surface of the metal flat plate can be measured under different loading pressures under the seepage action of different properties of underground water, different seepage negative pressures, different time and other conditions under different dry densities; and a basis is provided for adhesion evaluation during shield tunneling in soil under the action of underground water seepage under different conditions in actual engineering.

Description

Technical Field

[0001] The invention belongs to the technical field of tunnel and underground space engineering, and particularly relates to an experimental device and method for measuring the adhesion strength of the interface between soil and a shield cutter head under the action of seepage flow. Background Art

[0002] As a main tool for subway construction, the earth pressure balance shield has the advantages of less impact on the surrounding environment, fast construction speed, stable excavation working face, high efficiency, low labor intensity of workers, and no need for mud treatment equipment. When the shield machine tunnels in cohesive soil, due to the action of groundwater and the propulsion force, the excavated soil often adheres to the cutter and the transportation system, causing blockage, which limits the tunneling speed of the shield, aggravates the wear of the cutter head, delays the construction period, and increases the construction cost.

[0003] Seepage is an important cause of soil structure damage and the change of its engineering properties. When the soil undergoes seepage of groundwater with various properties, a series of physical and chemical interactions between water and soil will inevitably lead to changes in the soil composition, structure and its engineering properties, and then have an unknown impact on the behavior of the soil adhering to the cutter head during shield excavation. Therefore, it is of great significance to explore the variation law and mechanism of the influence of groundwater seepage on soil adhesion characteristics for tunnel engineering using shields.

[0004] Regarding the many factors affecting soil adhesion, the existing research mainly focuses on factors such as soil properties and water content. Due to the limitations of experimental equipment and experimental methods, no research has considered the influence of seepage on soil adhesion. The invention proposes an experimental device and method that can measure the soil adhesion characteristics under the action of seepage, filling the technical gap in the measurement of soil adhesion characteristics in existing research. Summary of the Invention

[0005] The technical problem to be solved by the invention is to provide an experimental device and method for measuring the adhesion strength of the interface between soil and a shield cutter head under the action of seepage flow in view of the above-mentioned deficiencies of the existing technology. The device and method mainly simulate the working conditions of cohesive soil under the action of groundwater seepage and cohesive soil acting on the metal surface with different pressures through a soil sample negative pressure seepage device and an adhesion strength measuring device, and measure the adhesion strength under the above-mentioned working conditions, so as to obtain the measurement data of the adhesion strength of the interface between soil and a shield cutter head under the action of groundwater seepage.

[0006] To solve the above technical problems, the technical solution adopted by the present invention is: an experimental device for measuring the adhesion strength of the soil-shield cutter head interface under seepage action, which is characterized in that it includes a soil sample negative pressure seepage device and an adhesion strength measurement device. The soil sample negative pressure seepage device includes a bracket and a penetrator; a gripper is installed on the bracket, and the penetrator is clamped on the gripper; a water supply system is installed on the bracket and above the penetrator. The water supply system includes a water supply tank and a water inlet pipe. The lower part of the water supply tank is provided with a water outlet, and the water inlet pipe is connected to the water outlet;

[0007] The penetrator includes a seepage top cover, a silica gel tube, a first permeable stone, a soil sample container, a second permeable stone and a seepage bottom cover. Through holes are provided on both the seepage top cover and the seepage bottom cover. The seepage top cover, the seepage bottom cover, the first permeable stone, the second permeable stone and the soil sample container have the same outer diameter. The inner diameter of the silica gel tube is slightly smaller than the outer diameter of the soil sample container. Both the upper and lower parts of the soil sample container are open;

[0008] A negative pressure system is arranged on the bracket and below the penetrator. The negative pressure system includes a vacuum barrel, a sealing cover, an air extraction pipe and a vacuum pump. The sealing cover is provided with a water inlet, an air outlet and a pressure gauge for monitoring the pressure inside the barrel. The air outlet is connected to the vacuum pump through the air extraction pipe;

[0009] The adhesion strength measurement device includes a pulling system. The pulling system includes a telescopic motor, a force transmission rod, a tensile force sensor and a metal plate. One end of the force transmission rod is connected to the telescopic motor, the other end of the force transmission rod is connected to the metal plate, and the tensile force sensor is installed on the force transmission rod.

[0010] The above experimental device for measuring the adhesion strength of the soil-shield cutter head interface under seepage action is characterized in that the bracket includes a base and a vertical rod. The vertical rod is vertically fixed on the base, and the gripper is movably installed on the vertical rod.

[0011] The above experimental device for measuring the adhesion strength of the soil-shield cutter head interface under seepage action is characterized in that the pulling system further includes a frame. The frame includes a top plate and a bottom plate arranged at intervals, and the telescopic motor is installed on the top plate.

[0012] The above experimental device for measuring the adhesion strength of the soil-shield cutter head interface under seepage action is characterized in that a positioner for determining the placement position of the soil sample container, a fixing seat and fixing bolts for fixing the soil sample container are arranged on the bottom plate.

[0013] The above experimental equipment for measuring the adhesion strength of the soil-shield cutter head interface under seepage action is characterized in that it further includes a controller, and the controller is electrically connected to the telescopic motor and the tension sensor respectively. The controller can control the telescopic motor and display the reading of the tension sensor.

[0014] The above experimental equipment for measuring the adhesion strength of the soil-shield cutter head interface under seepage action is characterized in that the penetrator is composed of the seepage top cover, the first permeable stone, the soil sample container, the second permeable stone and the seepage bottom cover stacked in sequence and then tightened with the silica gel tube.

[0015] The above experimental equipment for measuring the adhesion strength of the soil-shield cutter head interface under seepage action is characterized in that the edges of the seepage top cover, the soil sample container and the seepage bottom cover are all chamfered for easy installation.

[0016] Furthermore, the present invention provides a method for measuring the soil adhesion strength at the interface between the shield cutter head and the soil under seepage action by using the above experimental equipment, which is characterized by including the following steps:

[0017] Step 1: Prepare the soil sample, specifically including: calculating the soil mass according to the following formula, mixing soil and water according to the preset dry density and initial water content, and filling the soil sample container after fully stirring evenly. The soil mass calculation formula is:

[0018] m = ρ d ·(1 + ω)·V

[0019] where m is the required soil mass, in g; ρ d is the soil dry density, in g / cm 3 ; ω is the initial water content of the soil sample, in 1; V is the internal volume of the soil sample container, in cm 3 .

[0020] Step 2: Assemble the penetrator, specifically including: stacking the seepage top cover, the first permeable stone, the soil sample container filled with the soil sample, the second permeable stone and the seepage bottom cover in sequence. Filter paper can be placed between the soil sample container and the first permeable stone and between the soil sample container and the second permeable stone, and then the silica gel tube is sleeved outside to ensure that all components are closely fitted;

[0021] Step 3: Assemble the seepage device, specifically including: fixing the penetrator with a clamp, connecting the water supply tank and the seepage top cover with an inlet pipe after ensuring the soil sample is horizontal, connecting the seepage bottom cover and the water inlet with an outlet pipe, and connecting the air outlet and the vacuum pump with an extraction pipe;

[0022] Step 4: Add seepage solution to the water supply tank;

[0023] Step 5: Turn on the vacuum pump to maintain the negative pressure in the vacuum barrel at the required level and start the seepage;

[0024] Step 6: After the seepage ends, turn off the vacuum pump, remove the soil sample container containing the soil sample, and weigh it;

[0025] Step 7: Place the soil sample container containing the soil sample on the bottom plate according to the locator, and tighten the fixing bolts to fix the soil sample container;

[0026] Step 8: Control the telescopic motor to lower the force transfer rod so that the metal plate contacts the surface of the soil sample, and maintain a certain pressure to load the soil sample;

[0027] Step 9: Control the telescopic motor to raise the force transfer rod so that the metal plate separates from the surface of the soil sample, record the maximum tension of the tension sensor during the separation process, and denote it as Fmax;

[0028] Step 10: Calculate the adhesion strength between the soil sample and the metal interface according to the formula. The adhesion strength calculation formula is as follows:

[0029]

[0030] where α is the adhesion strength between the soil and the metal interface, with the unit of Pa; F max is the maximum tension, with the unit of N; m is the mass of the metal plate, with the unit of kg; g is the acceleration due to gravity, taking 10 N / kg; D is the inner diameter of the sample container, with the unit of m.

[0031] The present invention has the following advantages compared with the prior art:

[0032] 1. The present invention mainly realizes the simulation of working conditions such as the seepage of cohesive soil under the action of groundwater and the action of cohesive soil on the metal surface under different pressures through the soil sample negative pressure seepage device and the adhesion strength measurement device, and the determination of the adhesion strength under the above working conditions, and can obtain the measurement data of the adhesion strength between the soil and the shield cutter head interface under the action of groundwater seepage.

[0033] 2. The experimental equipment of the present invention includes an independent soil sample container with openings at both the top and bottom, which can be freely switched between the soil sample negative pressure seepage equipment and the adhesion strength measurement equipment, reducing the disturbance to the internal structure of the soil body and the surface of the soil sample, and making the measurement of the adhesion strength between the soil and the shield cutter head interface under the seepage action more accurate.

[0034] 3. The water supply tank of the present invention can hold electrolyte solutions of different types and concentrations, and the negative pressure system can control different magnitudes of negative pressure. Through the water supply system and the negative pressure system, seepage of groundwater with different physical and chemical properties and different seepage flows is carried out on the soil sample, and the response law of the adhesion strength between the soil and the shield cutter head interface under the actual groundwater seepage action can be obtained.

[0035] 4. In addition to being able to reproduce different shield excavation conditions, the soil sample negative pressure seepage device of the present invention can further increase the saturation degree of the soil sample, avoiding the difference between the saturation degree of the soil sample and the actual situation, which may lead to the distortion of the response law of the adhesion strength at the interface between the soil and the shield cutter head.

[0036] 5. The adhesion strength measuring device of the present invention is easy to operate. When measuring, the displacement size of the metal plate per unit time is set by the telescopic motor, and the adhesion force is measured in combination with the tension sensor, realizing the accurate measurement of the adhesion force and reducing the interference of other factors when using traditional measuring equipment.

[0037] 6. The equipment of the present invention can measure the adhesion strength between different types of cohesive soils with different dry densities and metal flat plate surfaces under the seepage action of different properties of groundwater, different seepage negative pressures, different times, etc. under different loading pressures, providing a basis for the adhesion evaluation during shield tunneling in soils under the seepage action of groundwater in different situations. It fills the research gap in the existing shield adhesion research that does not consider the influence of groundwater seepage on the adhesion strength, and at the same time overcomes the problems of expensive experimental equipment and complex operation procedures in the current adhesion research.

[0038] The following combines the drawings and embodiments to make a further detailed description of the technical solution of the present invention. Description of the Drawings

[0039] Figure 1 It is a schematic structural diagram of the soil sample negative pressure seepage device in the experimental equipment for measuring the adhesion strength at the interface between the soil and the shield cutter head under the seepage action of the present invention.

[0040] Figure 2 It is a schematic structural diagram of the adhesion strength measuring device in the experimental equipment for measuring the adhesion strength at the interface between the soil and the shield cutter head under the seepage action of the present invention.

[0041] Figure 3 It is a schematic structural diagram of the penetrator of the present invention.

[0042] Figure 4 It is a schematic diagram of the details of the bottom plate of the present invention.

[0043] Figure 5 It is a curve showing the change of the adhesion force with the seepage time of loess after the seepage action of deionized water in Example 2 of the present invention.

[0044] Figure 6 It is a curve showing the change of the adhesion force with the electrolyte concentration of loess in Example 2 of the present invention under the seepage action of different concentrations and different types of electrolyte solutions under the same loading pressure.

[0045] Description of the Reference Numerals:

[0046] 11—Base; 12—Vertical rod; 13—Clamp

[0047] 2—Water supply tank; 3—Water inlet pipe; 4—Permeator

[0048] 41—Seepage top cover; 42—Silicone tube; 43—First permeable stone

[0049] 44—Soil sample container; 45—Second permeable stone; 46—Seepage bottom cover

[0050] 5—Outlet pipe; 61—Vacuum barrel; 62—Sealing cover

[0051] 63—Inlet; 64—Pressure gauge; 65—Outlet for gas

[0052] 7—Suction pipe; 8—Vacuum pump; 91—Top plate

[0053] 92—Bottom plate; 10—Retractable motor; 14—Force transfer rod

[0054] 15—Tensile sensor; 16—Metal plate; 17—Locator

[0055] 18—Fixed seat; 19—Fixed bolt; 20—Controller Specific implementation mode

[0056] To make the above objects, features and advantages of the present invention more obvious and understandable, the specific implementation mode of the present invention will be described in detail below with reference to the embodiments. Unless otherwise specified, the technical means used in the following embodiments are conventional means well known to those skilled in the art. The materials, reagents, etc. used in the following embodiments can be obtained from commercial channels unless otherwise specified

[0057] The content of the present invention will be specifically described below with reference to the embodiments. The following description is not a limitation of the present invention

[0058] Embodiment 1

[0059] As Figures 1 to 4 shown, the experimental equipment for measuring the adhesion strength of the soil - shield cutter head interface under seepage in this embodiment includes a soil sample negative pressure seepage device and an adhesion strength measurement device

[0060] The soil sample negative pressure seepage device includes a bracket and a permeator 4; a clamp 13 is installed on the bracket, and the permeator 4 is clamped on the clamp 13; a water supply system is installed above the permeator 4 on the bracket, and the water supply system includes a water supply tank 2 and a water inlet pipe 3. The lower part of the water supply tank 2 is provided with a water outlet, and the water inlet pipe 3 is connected to the water outlet

[0061] The penetrator 4 includes a seepage top cover 41, a silica gel tube 42, a first permeable stone 43, a soil sample container 44, a second permeable stone 45, and a seepage bottom cover 46. Through holes are provided on both the seepage top cover 41 and the seepage bottom cover 46. The seepage top cover 41, the seepage bottom cover 46, the first permeable stone 43, the second permeable stone 45, and the soil sample container 44 have the same outer diameter. The inner diameter of the silica gel tube 42 is slightly smaller than the outer diameter of the soil sample container 44. Both the upper and lower parts of the soil sample container 44 are open.

[0062] A negative pressure system is provided on the bracket and below the penetrator 4. The negative pressure system includes a vacuum barrel 61, a sealing cover 62, an air extraction pipe 7, and a vacuum pump 8. The sealing cover 62 is provided with a water inlet 63, an air outlet 65, and a pressure gauge 64 that can monitor the pressure inside the barrel. The air outlet 65 is connected to the vacuum pump 8 through the air extraction pipe 7.

[0063] In this embodiment, the vacuum pump 8 is an RS-1 type rotary vane vacuum pump, purchased from Nanjing Whale Bow Sports Goods Co., Ltd.

[0064] The adhesion strength measuring device includes a pulling system. The pulling system includes a telescopic motor 10, a force transmission rod 14, a tension sensor 15, and a metal plate 16. One end of the force transmission rod 14 is connected to the telescopic motor 10, and the other end of the force transmission rod 14 is connected to the metal plate 16. The tension sensor 15 is installed on the force transmission rod 14.

[0065] In this embodiment, the telescopic motor 10 is a BJXL type stepping electric push rod machine, purchased from Longyi Technology Manufacturing Factory; the tension sensor 15 is an SBT620 type tension sensor, purchased from Guangzhou Sibatuo Electronic Technology Co., Ltd.

[0066] In this embodiment, the bracket includes a base 11 and a vertical rod 12. The vertical rod 12 is vertically fixed on the base 11. The gripper 13 is movably installed at any position on the vertical rod 12.

[0067] In this embodiment, the pulling system further includes a frame. The frame includes a top plate 91 and a bottom plate 92 arranged at intervals. The telescopic motor 10 is installed on the top plate 91.

[0068] In this embodiment, a locator 17 for determining the placement position of the soil sample container 44, a fixing seat 18 for fixing the soil sample container, and fixing bolts 19 are provided on the bottom plate 92.

[0069] In this embodiment, a controller 20 is further included. The controller 20 is electrically connected to the telescopic motor 10 and the tension sensor 15 respectively. The controller 20 can control the telescopic motor 10 and display the reading of the tension sensor 20.

[0070] In this embodiment, the permeator 4 is composed of a seepage top cover 41, a first permeable stone 43, a soil sample container 44, a second permeable stone 45, and a seepage bottom cover 46 stacked in sequence and tightened with a silica gel tube 42.

[0071] In this embodiment, chamfers are made at the edges of the seepage top cover 41, the soil sample container 44, and the seepage bottom cover 46 to facilitate installation.

[0072] In this embodiment, the metal plate 16 is made of stainless steel.

[0073] Embodiment 2

[0074] This embodiment provides a method for measuring the soil adhesion strength at the interface between a shield cutter head and soil under seepage using the experimental equipment for measuring the adhesion strength at the interface between soil and a shield cutter head under seepage in Embodiment 1, specifically including:

[0075] Step 1: Prepare a soil sample, specifically including: calculate the soil mass according to the following formula, mix soil and water according to a preset dry density and an initial water content, and fill the soil sample container 44 after fully stirring evenly. The preset dry density is 1.5 g / cm 3 ; the initial water content is 13%; the soil is loess; the soil mass calculation formula is: the soil mass calculation formula is:

[0076] m = ρ d ·(1 + ω)·V;

[0077] where m is the required soil mass, in g; ρ d is the soil dry density, in g / cm 3 ; ω is the initial water content of the soil sample, in 1; V is the internal volume of the soil sample container, in cm 3 .

[0078] Step 2: Assemble the permeator 4, specifically including: stack the seepage top cover 41, the first permeable stone 43, the soil sample container 44 filled with the soil sample, the second permeable stone 45, and the seepage bottom cover 46 in sequence. Filter paper can be placed between the soil sample container 44 and the first permeable stone 43 and between the soil sample container 44 and the second permeable stone 45, and then the silica gel tube 42 is sleeved outside, and it is ensured that the components are closely fitted;

[0079] Step 3: Assemble the seepage device, specifically including: fix the permeator 4 with a gripper 13, connect the water supply tank 2 and the seepage top cover 41 with a water inlet pipe 3 after ensuring the soil sample is horizontal, connect the seepage bottom cover 46 and the water inlet 63 with a water outlet pipe 5, and connect the air outlet 65 and the vacuum pump 8 with an air extraction pipe 7;

[0080] Step 4: Add the seepage solution into the water supply tank 2; the seepage solution is deionized water and KCl, MgCl2, and FeCl3 solutions with concentrations of 1%, 5%, 10%, 15%, and 20%.

[0081] Step 5: Turn on the vacuum pump 8 to maintain the negative pressure inside the vacuum barrel 61 at the required magnitude and start seepage; the negative pressure inside the barrel is 0.8 MPa, the seepage time of deionized water is 0 - 7 hours; the seepage time of the electrolyte solution is 3 h.

[0082] Step 6: After the seepage ends, turn off the vacuum pump 8, remove the soil sample container 44 containing the soil sample, and weigh it.

[0083] Step 7: Place the soil sample container 44 containing the soil sample on the bottom plate 92 according to the locator 17, and tighten the fixing bolt 19 to fix the soil sample container 44.

[0084] Step 8: Control the telescopic motor 10 to lower the force transmission rod 14 so that the metal plate 16 contacts the surface of the soil sample, maintain a certain pressure to load the soil sample, the loading pressure is 2 kPa, and the loading time is 1 min.

[0085] Step 9: Control the telescopic motor 10 to raise the force transmission rod 14 at a speed of 5 mm / min so that the metal plate 16 separates from the surface of the soil sample, record the maximum tensile force of the tensile force sensor during the separation process, and denote it as Fmax.

[0086] Step 10: Calculate the adhesion strength between the soil sample and the metal interface according to the formula. The adhesion strength calculation formula is as follows:

[0087]

[0088] where α is the adhesion strength between the soil and the metal interface, with the unit of Pa; Fmax is the maximum tensile force, with the unit of N; m is the mass of the metal plate, with the unit of kg; g is the acceleration due to gravity; D is the inner diameter of the soil sample container, with the unit of m.

[0089] Figure 5 is the adhesion force of the loess in Example 2 after being seeped with deionized water for different times. From Figure 5 It can be seen that as the seepage time increases, the adhesion force of the soil sample basically reaches a stable state after the seepage time reaches 180 min, about 4.6 N. Therefore, it is recommended that the seepage time should not be less than 3 h during the experiment to make the seepage reach a stable state. Figure 6 is the curve of the adhesion force of the loess in Example 2 varying with the electrolyte concentration under the seepage action of different concentrations and different types of electrolyte solutions under the same loading pressure. According to Figure 6It can be seen that when the seepage solution is KCl solution, with the increase of the electrolyte concentration, the adhesion force does not show an obvious change trend and remains at about 4.6 N all the time; when the seepage solution is MgCl2 solution, with the increase of the electrolyte concentration, the adhesion force reaches the maximum of about 6 N at the electrolyte concentration of 1%, and with the further increase of the electrolyte concentration, the adhesion force decreases slightly; when the seepage solution is FeCl3 solution, the adhesion force rapidly increases to about 8 N when the electrolyte concentration increases from 0% to 1%, and with the further increase of the electrolyte concentration, the adhesion force first increases and then decreases. The adhesion force increases with the increase of the valence state of the electrolyte cation. Because with the increase of the cation valence state, the compression effect of metal cations on the soil double layer during the seepage process gradually enhances, which makes the soil with a higher valence state cation seepage have a thinner double layer, which increases the van der Waals force between soil particles and the metal surface, thus resulting in a greater adhesion force.

[0090] As described above, it is only a preferred embodiment of the present invention and does not impose any limitation on the present invention. Any simple modification, change and equivalent structural change made to the above embodiments according to the technical essence of the invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. An experimental device for measuring the adhesion strength of the interface between soil and a shield cutter head under seepage action, characterized in that, It includes a soil sample negative pressure seepage device and an adhesion strength measurement device. The soil sample negative pressure seepage device includes a bracket and a penetrator (4); a gripper (13) is installed on the bracket, and the penetrator (4) is clamped on the gripper (13); a water supply system is installed on the bracket and above the penetrator (4). The water supply system includes a water supply tank (2) and a water inlet pipe (3). The lower part of the water supply tank (2) is provided with a water outlet, and the water inlet pipe (3) is connected to the water outlet; The penetrator (4) includes a seepage top cover (41), a silica gel tube (42), a first permeable stone (43), a soil sample container (44), a second permeable stone (45) and a seepage bottom cover (46). Through holes are provided on both the seepage top cover (41) and the seepage bottom cover (46). The seepage top cover (41), the seepage bottom cover (46), the first permeable stone (43), the second permeable stone (45) and the soil sample container (44) have the same outer diameter. The inner diameter of the silica gel tube (42) is slightly smaller than the outer diameter of the soil sample container (44). Both the upper and lower parts of the soil sample container (44) are open; A negative pressure system is arranged on the bracket and below the penetrator (4). The negative pressure system includes a vacuum bucket (61), a sealing cover (62), an air extraction pipe (7) and a vacuum pump (8). The sealing cover (62) is provided with a water inlet (63), an air outlet (65) and a pressure gauge (64) that can monitor the pressure inside the bucket. The air outlet (65) and the vacuum pump (8) are connected through the air extraction pipe (7); The adhesion strength measurement device includes a pulling system. The pulling system includes a telescopic motor (10), a force transmission rod (14), a tension sensor (15) and a metal plate (16). One end of the force transmission rod (14) is connected to the telescopic motor (10), and the other end of the force transmission rod (14) is connected to the metal plate (16). The tension sensor (15) is installed on the force transmission rod (14).

2. The experimental equipment for measuring the adhesion strength of the soil and the shield cutter head interface under seepage action according to claim 1, characterized in that The bracket includes a base (11) and a vertical rod (12). The vertical rod (12) is vertically fixed on the base (11), and the gripper (13) is movably installed on the vertical rod (12).

3. The experimental equipment for measuring the adhesion strength of the soil and the shield cutter head interface under seepage action according to claim 1, characterized in that, The pulling system further includes a frame. The frame includes a top plate (91) and a bottom plate (92) arranged at intervals. The telescopic motor (10) is installed on the top plate (91).

4. The experimental equipment for measuring the adhesion strength of the soil and the shield cutter head interface under seepage action according to claim 1, characterized in that, A positioner (17) for determining the placement position of the soil sample container (44), a fixing seat (18) for fixing the soil sample container and a fixing bolt (19) are arranged on the bottom plate (92).

5. The experimental equipment for measuring the adhesion strength of the soil and the shield cutter head interface under seepage action according to claim 1, characterized in that, It further includes a controller (20). The controller (20) is electrically connected to the telescopic motor (10) and the tension sensor (15) respectively. The controller (20) can control the telescopic motor (10) and display the reading of the tension sensor (20).

6. The experimental equipment for measuring the adhesion strength of the soil and the shield cutter head interface under seepage action according to claim 1, characterized in that, The penetrator (4) is composed of the seepage top cover (41), the first permeable stone (43), the soil sample container (44), the second permeable stone (45) and the seepage bottom cover (46) stacked in sequence and then tightened with the silica gel tube (42).

7. The experimental equipment for measuring the adhesion strength of the soil and the shield cutter head interface under seepage action according to claim 1, characterized in that, The edges of the seepage top cover (41), the soil sample container (44) and the seepage bottom cover (46) are all chamfered for easy installation.

8. A method for measuring the soil adhesion strength at the interface between the shield cutter head and the soil under the action of seepage using the experimental equipment described in any one of claims 1 to 7, characterized in that, It includes: Step 1: Prepare the soil sample, specifically including: calculating the soil mass according to the following formula, mixing soil and water according to the preset dry density and initial water content, and filling the soil sample container after fully stirring evenly. The soil mass calculation formula is: m = ρ d ·(1 + ω)·V; where m is the required soil mass in g; ρ d is the dry density of the soil in g / cm 3 ; ω is the initial moisture content of the soil sample in 1; V is the internal volume of the soil sample container in cm 3 . Step 2: Assemble the permeameter (4), specifically including: stacking the seepage top cover (41), the first permeable stone (43), the soil sample container (44) filled with the soil sample, the second permeable stone (45) and the seepage bottom cover (46) in sequence. Filter paper can be placed between the soil sample container (44) and the first permeable stone (43) and between the soil sample container (44) and the second permeable stone (45). Then, put the silica gel tube (42) on the outside and ensure that all components are closely fitted; Step 3: Assemble the seepage device, specifically including: fixing the permeameter (4) with the gripper (13), connecting the water supply tank (2) and the seepage top cover (41) with the water inlet pipe (3) after ensuring the soil sample is horizontal, connecting the seepage bottom cover (46) and the water inlet (63) with the outlet pipe (5), and connecting the air outlet (65) and the vacuum pump (8) with the air extraction pipe (7); Step 4: Add seepage solution to the water supply tank (2); Step 5: Turn on the vacuum pump (8) to maintain the negative pressure in the vacuum barrel (61) at the required value to start seepage; Step 6: After the seepage ends, turn off the vacuum pump (8), remove the soil sample container (44) filled with the soil sample and weigh it; Step 7: Place the soil sample container (44) filled with the soil sample on the bottom plate (92) according to the locator (17), and tighten the fixing bolt (19) to fix the soil sample container (44); Step 8: Control the telescopic motor (10) to lower the force transmission rod (14) so that the metal plate (16) contacts the soil sample surface, and maintain a certain pressure to load the soil sample; Step 9: Control the telescopic motor (10) to raise the force transmission rod (14) so that the metal plate (16) separates from the soil sample surface, and record the maximum tension of the tension sensor during the separation process, denoted as Fmax; Step 10: Calculate the adhesion strength between the soil sample and the metal interface according to the formula. The adhesion strength calculation formula is: where α is the adhesion strength at the soil-metal interface, with the unit of Pa; F max is the maximum tensile force, with the unit of N; m is the mass of the metal plate, with the unit of kg; g is the acceleration due to gravity; D is the inner diameter of the soil sample container, with the unit of m.

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