WO2023202088A1

WO2023202088A1 - Mud cake formation prevention steel plate for shield cutter head, and simulation test table and test method for characteristic testing thereof

Info

Publication number: WO2023202088A1
Application number: PCT/CN2022/137067
Authority: WO
Inventors: 赵海雷; 曾垂刚; 王国安; 王利明; 李治国; 杨振兴; 韩伟锋; 王云峰; 王亚峰; 王世强; 陈纯洁; 王发民; 吴磊; 李晨阳; 杨新举; 翟乾智; 秦银平; 吕乾乾; 孙飞祥
Original assignee: 盾构及掘进技术国家重点实验室; 中铁隧道局集团有限公司
Priority date: 2022-04-15
Filing date: 2022-12-06
Publication date: 2023-10-26

Abstract

A mud cake formation prevention steel plate for a shield cutter head, and a simulation test table and test method for characteristic testing thereof. The steel plate is installed on a shield cutter head, is snap-fitted to a rake face (1) of a cutting bit on a cutter head, is consistent with the rake face (1) of the cutting bit on the cutter head in shape, position and size, and is connected to the rake face (1) by means of a bolt; the steel plate is made of one of molybdenum-vanadium alloy and Q235/Q245, and the smoothness of the upper surface thereof is less than 0.1. Equivalently, a layer of tempered film beneficial to mud sliding is additionally arranged on the cutting bit, and the tempered film has a set of detection platform so as to be adjusted and replaced in real time under different working conditions. Information of a cutting face can be quickly obtained, and the problem in the prior art that mud cake formation on a shield cutter head affects the outflow of mud, and thus affects the overall working state is solved.

Description

An anti-mud cake steel plate for shield cutterhead and a simulation test bench and test method for its characteristic testing

Technical field

The invention relates to a testing device for shield construction equipment, and in particular to an anti-sludge cake steel plate for a shield cutterhead and a simulation test bench and test method for characteristic testing thereof.

Background technique

In shield tunneling operations, the strata at the top of the tunnel are mainly silty clay, silty sand, clay, breccia soil, and pebble soil. The strata that the tunnel passes through include: 16% silty clay, 11% silty sand, 8% clay, 15% breccia soil, 5% pebble soil, 25% strongly weathered mudstone, and 14% weathered mudstone. , moderately weathered gravelly muddy sandstone accounts for 2%. Karst also exists in local locations.

Clay and strongly weathered mudstone contain a large amount of viscous minerals and have strong soil adhesion. The sticky particles have a certain ability to absorb water, expand and adsorb. The clay cut by the tool easily adheres to the cutterhead panel and the cutterhead opening, and is difficult to flow out of the bin. It is prone to stagnant discharge and accumulation at the bottom of the bin. Adhesion The cohesive soil on the cutterhead forms a mud cake on the cutterhead panel under the action of extrusion, and the mud cakes the cutterhead opening, causing poor circulation in the warehouse and reducing the tunneling efficiency. Over 2,400 meters, the prevention and control of mud cake on the cutterhead during the shield tunneling process of this project is a major difficulty.

At this stage, the analysis and prediction of cutterhead mud cake data are mainly focused on simulating on-site working conditions. For example, in the published Chinese patent documents, the application number is CN201810116195.4, which is called a soil cutting machine. The patented experimental device and method for simulating mud cake on the pressure-balanced shield cutterhead. By simulating the tunneling of the shield in specific soil, adjusting the cutter layout and construction parameters, and observing the distribution and shape of the mud cake, it provides a basis for studying the mud cake phenomenon. Provide the basis for the generation mechanism and mud cake prevention and disposal methods. Another example is the application number CN 202110140730.1, which is called a simulation system for regulating mud cake on the shield cutterhead. It also provides a basis for mud cake prevention and disposal methods through the simulation of the cutterhead.

However, the applicant believes that the current technology mainly lies in simulating the cutterhead system, measuring the real-time temperature and pressure on the cutterhead, and then improving the cutterhead based on the sample conditions. However, in actual operations, it is known that the cutting angle on the cutterhead, and The cutting temperature and adjustable space are actually very low, and most of the time it is not possible to make appropriate adjustments.

Contents of the invention

The purpose of the present invention is to solve the problem in the prior art that there is a lack of targeted simulation equipment and that in actual work, the agglomeration of mud on the shield cutterhead affects the flow of mud, thereby affecting the overall working state.

The specific solution of the present invention is to design an anti-sludge cake steel plate for a shield cutterhead, which is installed on the shield cutterhead. Specifically, it is clamped on the rake surface of the cutter head on the cutterhead and is connected with the upper blade of the cutterhead. The shape and size of the rake surface of the head are consistent and are connected to the rake surface via bolts. The steel plate is made of one of molybdenum vanadium alloy or Q235/Q245, and the upper surface smoothness is less than 0.1.

For this steel plate, it also relates to a simulation test bench for testing the characteristics of the steel plate, including a test bench. The test bench includes a lower storage support area and an upper equipment inclination angle area. The lower storage support area and the upper equipment inclination angle area are provided with The hinge structure components are connected by hinges. An experimental plate support platform driven by a two-way motor is installed in the inclination area of the upper equipment. The experimental plate support platform is installed on the door-shaped bracket and includes a bottom rotating shaft and a bottom rotating shaft. Claws on the shaft, the claws clamp an experimental board with a length of 40 to 60cm and a width of 40 to 60cm.

The rotating shaft is installed on the top of the portal bracket via a bearing, and its input end is connected to the output shaft of the bidirectional motor. The material of the experimental plate corresponds to the steel plate, and the corresponding material is made of molybdenum vanadium alloy, Q235/Q245 Made of one, the upper surface smoothness is less than 0.1, the lower storage support area is equipped with a mixing barrel, a sample box and a number of experimental plates to be tested. The sample box is a hollow cylindrical barrel with an inner diameter of less than 8cm. The sample box to be tested is The test board is vertically clamped in the lower storage support area.

The lower storage support area and the upper equipment inclination area are provided with an angle support measuring mechanism. The angle support measuring mechanism includes a chute rod and a locking bolt. The top end of the chute rod is connected to the upper equipment inclination angle via a rotating shaft. The bottom edge of the area, the chute rod is provided with a chute, the bottom frame of the upper equipment inclination area is provided with a horizontal groove, the locking bolt passes through the chute and the horizontal groove and is fixed to the upper part of the lower storage support area On the edge, the chute is provided with a scale line to guide the installation angle of the lower storage support area and the upper equipment inclination range. The lower surface smoothness of the experimental board is less than 0.16.

The two-way motor is also connected to a control mechanism, and the control mechanism is provided with a display screen and buttons to control the opening and closing, steering and rotation speed of the two-way motor.

A tension gauge positioning clip is mounted on the edge of the test board. The head of the tension gauge is hung on the tension gauge positioning clip, and the tail end is embedded in the sample box. The tension gauge positioning clip includes a [shaped clamp body and a clamp The body slides a roller mounted on the edge of the experimental board.

The surface of the experimental board is marked with marking lines drawn by a marker or marked lines projected by an optical mechanism. The optical mechanism includes a transverse light column that emits grid-like optical lines, and support columns on both sides of the transverse light column. The support column is clamped on the clamp.

It also relates to a test method for testing the properties of the steel plate in the mud cake of the shield, using the simulation experimental device for testing the properties of the steel plate in the mud cake of the shield, including the following steps.

(1) Clay preparation: (a) Weigh 300g of natural clay or simulated shield tunneling site cost clay, and pour it into a mixing bucket; (b) Weigh 20g of Grade II bentonite, pour it into the above mixing bucket, and mix it at 60-120 Stir evenly through the motor at a speed of 60-120 rpm; (c) Use a measuring cylinder to measure 100ml of tap water, slowly pour it into the above mixing barrel, and stir evenly again at a speed of 60-120 rpm; (d) Place the prepared Put the clay into a dry sample box, and weigh the total mass of the clay and sample box.

(2) Clay sliding starting angle test: (a) Select an imitation cutting surface panel with the same material as the cutting surface as the experimental board. The installation inclination of the experimental board relative to the horizontal plane is first adjusted to 0°, and then the sample box containing the clay is Place it on the upper part of the steel plate, with one end of the tensile gauge hung in the sample box and the other end hung on the edge of the test plate; (b) By causing the test plate to rotate, gradually adjust the rotational inclination of the test plate until the sample The box starts to rotate on the surface of the steel plate, records the sliding starting angle, and simultaneously measures the tensile force of the tensile gauge, which is converted into the friction force of the steel plate against the clay through calculation; (c) Use the same steps to make the installation inclination angles of the rotating shaft of the experimental plate respectively. Adjust to 5° and 10° to simulate the tilt of the cutter head, conduct repeated tests, and record the data to obtain the clay starting angle and starting tensile test data.

(3) Data analysis was used to determine the impact of the installation inclination angle on the starting angle, and to verify the mud viscous adsorption capacity of the material of the experimental plate.

A pre-step is added before step (1). The pre-step includes extracting 500g of clay from the site. The experimental plate is formed by stacking two layers of steel, molybdenum-vanadium alloy, 65Mn, and chromium-nickel alloy.

In the specific implementation, step (4) adjustment is also included. The step (4) adjustment includes introducing an auxiliary plate to improve the cutting surface friction when the starting angle at any installation angle is greater than 30 degrees in the result of step (3). The auxiliary plate and the cutting surface are fixed through hexagon socket bolts and screw holes. The test method for the performance of the auxiliary plate is as shown in steps (1) to (3).

In the specific implementation, in the step (2), the rotation speed is less than 6 rpm, and step (5) fatigue test is also included. The step (5) includes controlling the experimental plate to rotate in both directions within the starting angle for more than 3 days, Then measure the surface friction and flatness error of the area where the sample box is located on the experimental board.

In the specific implementation, step (1) is replaced by using a graduated cylinder to measure 20 ml of tap water to form clay B, and then measure the sliding starting angle of the experimental plate when the clay B is in the sample box.

The beneficial effects of the present invention are: different from the existing technology, it is proposed for the first time to study mud cakes, and then find the most suitable steel sheet for that year's mud cakes based on the data of the mud cakes. The further steel sheets are equivalent to adding a layer of benefit to the cutter head. The tempered membrane for mud sliding, and the tempered membrane itself has a detection platform, which can be adjusted and replaced in real time under different working conditions, greatly increasing the space for changing the properties of the cutter head.

Specifically, the blade installed on the rake surface of the cutter head, which is the main working surface, can greatly reduce the adhesion of mud on the main cutting surface due to its superior low surface friction characteristics. At the same time, different blade materials can It is suitable for different requirements of different excavation soil layers, while ensuring the cost, and maximizing the avoidance of clogging caused by the reciprocating beating of mud on the steel sheet; the double-sided design of the test board facilitates improved test efficiency and reduces the number of test boards.

The simulated test platform has a simple structure, occupies a small area, and can be operated by connecting a circuit. It has low requirements on the test site. The test results can basically be obtained on the spot. The test time is short. The cutting surface of the shield head can be simulated at multiple angles to ensure the test results. of precision. The operating platform can measure multiple sets of data at the same time and has various functions. In the present invention, through the study of the mud viscosity between the cutting surface and the mud, it can be concluded that what materials and at what angles there is a reciprocating flow, and the reciprocating flow is the mud channel. The key to congestion is found in the research of this invention. Data on the mud viscosity of blades of different materials under different working environments can be obtained, which can determine whether the mud channel will be blocked in specific work in the future. If there are hidden dangers, We can also promptly propose solutions to change the material of the cutting surface of the cutter head, and at the same time verify whether the solution is reasonable.

Description of the drawings

Figure 1 is a front view of the structure of the present invention.

Figure 2 is a top view of the structure of the present invention.

Figure 3 is a left side view of the structure of the present invention.

Figure 4 is a right side view of the structure of the present invention.

Figure 5 is a rear view of the structure of the present invention.

Fig. 6 is a rear view of another state of the present invention.

Figure 7 is a perspective view of the present invention.

Figure 8 is a perspective view from another angle of the present invention.

Figure 9 is a schematic diagram of the blade position of the blade involved.

Fig. 10 is a perspective view of another measurement state in the present invention.

Figure 11 is the relationship curve of the influence of inclination angle on the initial inclination angle of clay sliding.

Figure 12 is the relationship curve of the influence of multi-material inclination angle on the starting inclination angle of clay sliding.

Figure 13 is the fitting relationship between K and the critical speed of clay sliding on the steel plate.

Names of each component in the picture: 1. Rake surface; 2. Lower storage support area; 3. Upper equipment inclination area; 4. Hinge structural components; 5. Control mechanism.

21. Experimental plate support table; 22. Two-way motor; 23. Portal bracket; 24. Bottom rotating shaft; 25. Claw; 26. Experimental plate; 27. Bearing.

31. Locking bolt; 32. Chute; 33. Horizontal slot; 34. Experimental plate mounting clamp; 35. Mixing barrel; 36. Sample box mounting plate.

6. Sample box; 7. Tension gauge; 8. Tension gauge positioning clip; 9. Optical mechanism; 10. Plate; 11. Mud marks.

81. Clamp body; 82. Roller.

91. Support column; 92. Horizontal light column.

Detailed ways

The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described here are only used to illustrate and explain the present invention, and are not intended to limit the present invention.

Example 1

A simulation experimental device used to test the properties of steel plates in the mud cake formation of shields. Refer to Figures 1 to 9. An anti-mud cake steel plate for shield cutterheads is designed, which is installed on the shield cutterhead. Specifically The rake surface of the cutter head is clamped on the cutter head, and is consistent with the rake surface shape and size of the cutter head on the cutter head. It is connected to the rake surface through bolts. The steel plate is made of molybdenum vanadium alloy, Q235 Made of one of /Q245, the upper surface finish is less than 0.1. The function of the steel plate is to add a layer of protection to the surface of the cutterhead that passes through the mud to prevent mud from adhering.

For this steel plate, it also relates to a simulation test bench for testing the characteristics of the steel plate, including a test bench. The test bench includes a lower storage support area and an upper equipment inclination angle area. The lower storage support area and the upper equipment inclination angle area are provided with The hinge structure components are connected by hinges. An experimental plate support platform driven by a two-way motor is installed in the inclination area of the upper equipment. The experimental plate support platform is installed on the door-shaped bracket and includes a bottom rotating shaft and a bottom rotating shaft. The claws on the shaft hold an experimental board 40 to 60cm long and 40 to 60cm wide; the rotating shaft is installed on the top of the portal bracket via a bearing, and its input end is connected to the bidirectional motor. Output shaft, the test plate is made of the same material as the steel plate, and is made of one of molybdenum-vanadium alloys or Q235/Q245. The upper surface finish is less than 0.1. A mixing barrel, sample box and Several experimental boards to be tested, the sample box is in the shape of a hollow cylindrical barrel with an inner diameter of less than 8cm, and the experimental boards to be tested are vertically clamped in the lower storage support area.

(1) Clay preparation: (a) Weigh 300g of natural clay or simulated shield tunneling site cost clay, and pour it into a mixing bucket; (b) Weigh 20g of Grade II bentonite, pour it into the above mixing bucket, and mix it at 60-120 Stir evenly through the motor at a speed of 60-120 rpm; (c) Use a measuring cylinder to measure 100ml of tap water, slowly pour it into the above-mentioned mixing barrel, and stir evenly again at a speed of 60-120 rpm; (5) Place the prepared Put the clay into a dry sample box, and weigh the total mass of the clay and sample box.

During the work, two different types of mirror steel plates are used, namely Q345 steel plate and molybdenum vanadium alloy. Each steel plate has two different finishes, front and back. A multi-functional steel plate clamping device is used to adjust the steel plates to different angles. Fixed, record the starting angle of the clay sliding on the surface of the steel plate, the speed of the sliding and the amount of mud left. At the same time, use a tensile gauge to test the tensile force of the clay when it slides, and convert it into the sliding friction of the steel plate. First make clay, or sample the discharged mud soil from the construction layer, and then measure it on different test boards to measure its sliding angle, especially the static friction angle and sliding tension. After determining the most suitable experimental plate material, a steel plate of the same material is selected and installed on the blade, which can complete the transition from experiment to actual combat, achieve smooth output of mud during the excavation process, and prevent blockage caused by beating.

The following is an example of a single work process. First, prepare the clay: (1) Weigh 300g of natural clay and pour it into the mixing bucket; (2) Weigh 20g of grade II bentonite, pour it into the above mixing bucket, and stir evenly; (3) Use a graduated cylinder to measure 100ml of tap water , slowly pour into the above-mentioned mixing bucket, and stir evenly; (4) Put the prepared clay into a dry sample box, and weigh the total mass of the clay and sample box. Secondly, the clay sliding starting angle test was carried out. When working, adjust the inclination area of the upper equipment so that the installation inclination of the specially processed experimental plate is first adjusted to 0°, and then place the sample box containing clay on the upper part of the steel plate; (2) Gradually adjust the steel plate through the control system until the clay starts to rotate on the surface of the steel plate, record the sliding starting angle, and measure the tension of the tensile gauge at the same time, and convert it into the friction force of the steel plate against the clay through calculation; (3) Use the same steps to adjust the installation inclination angle of the steel plate Adjust to 5° and 10° respectively, conduct repeated tests, and record the data. The specific data are shown in Table 1.

Table 1 Clay starting angle and starting tensile test data.

Then conduct data analysis: Based on the experimental data, the influence of the installation inclination angle on the clay sliding initiation angle was analyzed. The study found that under this experimental condition, as the installation inclination angle increased, the clay sliding initiation angle gradually decreased, that is, as the installation inclination angle increased, the clay sliding initiation angle gradually decreased. The increase of the inclination angle is more and more conducive to the sliding of clay from the surface of the steel plate. As shown in Figure 11, taking Q345 steel plate, Ra0.012 as a representative, the relationship curve of the influence of the installation inclination angle on the starting inclination angle of clay sliding is drawn.

Furthermore, the influence of steel properties on the starting angle can be analyzed:

The characteristics of steel in this study mainly include the type of steel and the influence of smoothness. According to data analysis, as shown in Figure 4, through the comparison of curve Q345 (Ra0.012) and curve Q345 (Ra0.2), the molybdenum vanadium alloy curve (Ra0 .012) and the curve (Ra0.2), it can be concluded that for the same steel material, when the smoothness is different, it has a greater impact on the starting inclination angle of clay sliding, that is, the better the smoothness, the greater the starting angle under the same conditions. Small, that is, under the same slip length, it can buy more time for the clay to slide on the steel plate; by comparing the curve Q345 (Ra0.012) with the molybdenum vanadium alloy curve (Ra0.012), the curve Q345 (Ra0.2) Comparing with the molybdenum-vanadium alloy curve (Ra0.2), it can be concluded that for different steel materials with the same smoothness, the molybdenum-vanadium alloy steel plate has a better anti-sludge cake effect than the Q345 steel plate. Molybdenum vanadium alloy can be specifically Cr12, Cr16, Cr20, Q235 can also be replaced by Q225, Q245. Furthermore, the influence of steel properties on clay sliding friction was analyzed.

In view of the fact that the sliding friction force of the indoor test steel plate against the clay is not easy to obtain directly, the method of directly measuring the pulling force when the clay slides is used. According to F sliding force = F pulling force + F friction force, the friction force when the clay slides down is converted. That is, when the sliding force is constant, the greater the measured pulling force, the smaller the friction force the clay receives when sliding down, and the less likely it is for mud cake to form. In order to facilitate calculation, this analysis adopts the installation inclination angle of 0°. The total mass of the clay box sample box is 286g. The specific tensile test data and calculated friction force are shown in Table 4. Through Q345 (Ra0.012) and Comparison of friction data of Q345 (Ra0.2), as well as friction data of molybdenum vanadium alloy (Ra0.012) and molybdenum vanadium alloy (Ra0.2) shows that for the same steel plate, the higher the smoothness, the smaller the friction; through Q345 Comparing the friction data of (Ra0.012) and molybdenum vanadium alloy (Ra0.012), and comparing the friction data of Q345 (Ra0.2) and molybdenum vanadium alloy (Ra0.2), it can be seen that when the smoothness is the same, the molybdenum vanadium alloy steel plate The friction force on the clay is less than the friction force on the Q345 steel plate. The test process is shown in Figure 5.

Table 2: Friction force statistics of different materials and smooth surfaces at an installation angle of 0°.

Furthermore, a test and analysis of the impact of cutterhead speed on mud cake was carried out.

Test steps: (1) Weigh the prepared clay, fix the contact area between the clay and the steel plate, ensure that the contact area remains consistent for each test, and then press the top of the clay with the same force to make the clay and the steel plate adhere;

(2) Adjust the multifunctional steel plate clamping device to rotate at different speeds and record the sliding condition of the clay on the steel plate;

(3) Weigh different masses of clay and repeat the above test.

Data analysis: Through the above tests, data on the impact of the cutterhead speed of the same steel plate and the same finish on the sliding of clay of different qualities were obtained, and the test phenomena were recorded. The test data are specifically shown in Table 3. From the data analysis in the table, it can be seen that for a fixed mass per unit area, the faster the steel plate rotates, the less conducive it is to the sliding of clay, and the easier it is to accumulate and form a mud cake. The specific phenomenon in the test is that as the steel plate rotates, the clay During the 0-360° rotation, it will swing back and forth without falling off. When the speed of the steel plate is below the critical speed, the soil will slide off the edge of the steel plate during the 0-180° rotation.

Table 3 Statistical table of the influence of steel plate speed on clay sliding.

Since the contact area between clay of different qualities and the steel plate is the same, the clay mass per unit area and the steel plate speed can be used to form a corresponding relationship to provide parameter basis for the on-site shield machine excavation penetration and cutterhead speed setting. The contact area between the fixed clay and the steel plate in this scheme is 50cm2, and the set mass of clay per unit area is represented by the symbol K. Based on the data in Table 3, a one-to-one correspondence between K and the critical speed of clay sliding on the steel plate is formed, as shown in Table 4. Figure 13 shows the fitting relationship between K and the critical speed of clay sliding on the steel plate.

Table 4 Correspondence between K and critical speed of steel plate clay sliding.

K(g/cm ²) K(g/cm ² )	33	44	55
临界转速(r/min)Critical speed (r/min)	11	22	33

Based on the data in Table 4, the data was fitted and the processing results are shown in Figure 12. The curve is approximately a straight line.

In the specific work, boards were erected over the lower storage support area to catch the falling mud cake.

Finally, test conclusions and suggestions are drawn for the case where clay is used as the material.

(1) For different installation inclination angles of the same steel plate, the greater the installation inclination angle, the smaller the starting angle of clay sliding, which is more conducive to the discharge of clay. It is recommended that the installation inclination angle be appropriately increased while ensuring the strength of the cutterhead opening.

(2) For different finishes of the same steel plate, the higher the surface finish, the smaller the clay sliding starting angle under the same installation inclination angle, which is more conducive to the discharge of clay soil soil. It is recommended that the rough steel plate surface at the opening of the existing shield machine's cutterhead be installed with a high-gloss mirror steel plate and field tests be carried out.

(3) Through the comparison of tests between Q345 steel plate and molybdenum-vanadium alloy steel plate, in terms of anti-sludge cake, molybdenum-vanadium alloy steel plate has better performance than Q345 steel plate, but compared with the rough surface of traditional steel, both steels can Obvious advantages. It is recommended that two kinds of steel plates be installed at the site where the cutterhead is supported for testing to determine which material is more economical and reasonable to use in the future.

(4) The speed of the cutterhead has a great influence on the sliding of clay on the steel plate. For clay with a certain unit area mass, when the speed of the cutterhead is below the critical speed, the clay can smoothly slide off the edge of the steel plate. When the speed of the cutterhead When the speed is above the critical speed, the stickiness will swing left and right with the 360° rotation of the steel plate, making it difficult to slip off the surface of the steel plate. It is recommended that when digging into strata prone to mud cake, the cutterhead speed should be adjusted in a timely manner according to the amount of slag.

In the specific implementation, by following the above method, targeted conclusions can be drawn for different soil conditions, and then combined with cost control, the most suitable material can be selected as steel sheets to be laid on the main cutting surface of shield cutting, adjusting and improving The channel condition of mud retention.

Finally, it should be noted that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, it is still The technical solutions described in the foregoing embodiments may be modified, or some of the technical features may be equivalently replaced. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

An anti-sludge cake steel plate for shield cutterheads, which is characterized in that: it is installed on the shield cutterhead, specifically clamped on the rake surface of the cutter head on the cutterhead, and the rake surface of the cutter head on the cutterhead. The shape and size are consistent and connected to the rake surface via bolts. The steel plate is made of one of molybdenum vanadium alloy or Q235/Q245, and the upper surface smoothness is less than 0.1.
A simulation test bench for testing the characteristics of steel plates, characterized by: including a test bench, the test bench includes a lower storage support area and an upper equipment inclination area, the lower storage support area and the upper equipment inclination area are provided with hinges The structural components are connected by hinges. An experimental plate support table driven by a bidirectional motor is installed in the inclination area of the upper equipment. The experimental plate support table is installed on the door-shaped bracket and includes a bottom rotating shaft and is installed on the bottom rotating shaft. Claws, the claws clamp an experimental board with a length of 40 to 60cm and a width of 40 to 60cm;

The rotating shaft is installed on the top of the portal bracket via a bearing, and its input end is connected to the output shaft of the bidirectional motor. The material of the experimental plate corresponds to the steel plate, and the corresponding material is made of molybdenum vanadium alloy, Q235/Q245 Made of one, the upper surface smoothness is less than 0.1, the lower storage support area is equipped with a mixing barrel, a sample box and a number of experimental plates to be tested. The sample box is a hollow cylindrical barrel with an inner diameter of less than 8cm. The sample box to be tested is The test board is vertically clamped in the lower storage support area.
The simulation experimental device for testing the properties of steel plates in shield mud cake performance as claimed in claim 1, characterized in that: the lower storage support area and the upper equipment inclination area are provided with angle support measurement mechanisms, and the angle support The measuring mechanism includes a chute rod and a locking bolt. The top of the chute rod is connected and installed on the bottom edge of the inclination area of the upper equipment through a rotating shaft. The chute rod is provided with a chute, and the bottom frame of the inclination area of the upper equipment is provided with a chute. There is a horizontal groove, and the locking bolt passes through the chute and the horizontal groove and is fixed on the upper edge of the lower storage support area. The chute is provided with a scale to guide the lower storage support area and the upper part. The installation angle of the equipment inclination range, the smoothness of the lower surface of the test board is less than 0.16.
The simulation experimental device for testing the properties of steel plates and the performance of shield mud cakes according to claim 1, characterized in that: the two-way motor is also connected to a control mechanism, and the control mechanism is provided with a display screen and buttons to Control the opening and closing, steering and rotation speed of the bidirectional motor.
The simulation experimental device for testing the properties of steel plates in shield mud cake performance as claimed in claim 3, characterized in that: the edge of the test plate is equipped with a tension meter positioning clip, and the head of the tension meter is hung on the On the tension gauge positioning clip, the tail end is embedded in the sample box. The tension gauge positioning clip includes a [shaped clamp body and a roller in the clamp body that is slidably mounted on the edge of the test plate.
The simulation experimental device for testing the properties of steel plates in the mud cake performance of shields as claimed in claim 2, characterized in that: the surface of the experimental plate is marked with marking lines drawn by a marker or marked lines projected by an optical mechanism. , the optical mechanism includes a transverse light column that emits grid-like optical lines, and support columns on both sides of the transverse light column, and the support columns are clamped on the clamp.
A test method for testing the properties of steel plates in the mud cake of a shield, using a simulation experimental device for testing the properties of steel plates in the mud cake of a shield as claimed in claim 2, characterized in that it includes the following steps:

(1) Clay preparation: (a) Weigh 300g of natural clay or simulated shield tunneling site cost clay, and pour it into a mixing bucket; (b) Weigh 20g of Grade II bentonite, pour it into the above mixing bucket, and mix it at 60-120 Stir evenly through the motor at a speed of 60-120 rpm; (c) Use a measuring cylinder to measure 100ml of tap water, slowly pour it into the above-mentioned mixing barrel, and stir evenly again at a speed of 60-120 rpm; (5) Place the prepared Put the clay into a dry sample box, and weigh the total mass of the clay and sample box;

(2) Clay sliding starting angle test: (a) Select an imitation cutting surface panel with the same material as the cutting surface as the experimental board. The installation inclination of the experimental board relative to the horizontal plane is first adjusted to 0°, and then the sample box containing the clay is Place it on the upper part of the steel plate, with one end of the tensile gauge hung in the sample box and the other end hung on the edge of the test plate; (b) By causing the test plate to rotate, gradually adjust the rotational inclination of the test plate until the sample The box starts to rotate on the surface of the steel plate, records the sliding starting angle, and simultaneously measures the tensile force of the tensile gauge, which is converted into the friction force of the steel plate against the clay through calculation; (c) Use the same steps to make the installation inclination angles of the rotating shaft of the experimental plate respectively. Adjust to 5° and 10° to simulate the tilt of the cutter head, conduct repeated tests, and record the data to obtain the clay starting angle and starting tensile test data;

(3) Data analysis to determine the impact of the installation inclination angle on the starting angle, and verify the mud viscous adsorption capacity of the experimental plate material;

A pre-step is added before step (1). The pre-step includes extracting 500g of clay from the site. The experimental plate is formed by stacking two layers of steel, molybdenum-vanadium alloy, 65Mn, and chromium-nickel alloy.
The method for testing the mud viscosity adsorption capacity of the cutting surface material in the shield cutterhead according to claim 7, characterized in that it further includes step (4) adjustment, and the step (4) adjustment includes when in step (3) In the results, when the starting angle at any installation angle is greater than 30 degrees, an auxiliary plate is introduced to increase the friction of the cutting surface. The auxiliary plate and the cutting surface are fixed through hexagon socket bolts and screw holes. The test method for the performance of the auxiliary plate is as follows: As shown in (1) to (3)
The method for testing the mud viscosity adsorption capacity of the cutting surface material in the shield cutterhead according to claim 7, characterized in that: in the step (2), the rotational speed of the rotation is less than 6 rpm, and further includes the step (5 ) Fatigue test, the step (5) includes controlling the experimental plate to rotate in both directions within the starting angle for more than 3 days, and then measuring the surface friction and flatness error of the area where the sample box is located on the experimental plate.
The method for testing the mud viscosity adsorption capacity of the cutting surface material in the shield cutterhead according to claim 7, characterized in that: in step (1), 20 ml of tap water is measured with a graduated cylinder to form clay B, and then the The sliding starting angle of the experimental plate when clay B is in the sample box.