A numerical simulation method for shield tool cutting reinforced concrete ground-connected wall

Abstract

The present invention discloses a numerical simulation method for shield tool cutting reinforced concrete ground-connected wall. The SOLIDWORKS three-dimensional drawing software is used to establish a cutter head body, a cutter and a reinforced concrete ground-connected wall model. Subsequently, in the ABAQUS finite element software, the material parameters, constraints, interactions and boundary conditions of each component of the three-dimensional model are defined respectively, so that the numerical simulation is closer to the actual cutting effect and reliable simulation data is obtained. The present invention proposes a rare numerical simulation method in China, which saves the manpower cost and material cost required for indoor or field tests. The cutting effect under different working conditions can be provided by changing the number of cutters, the layout position and the shield tunneling speed, thereby obtaining a better cutter head configuration and tunneling parameters, and providing a reference basis for actual engineering.

Description

Technical Field

[0001] The invention belongs to the technical field of shield engineering, and in particular relates to a numerical simulation method for shield tool cutting reinforced concrete ground-connected walls. Background Art

[0002] With the rapid development of rail transit, the subway network has gradually taken shape. During the construction process, it is common for new line tunnels to pass under existing stations. When building subway stations in my country, underground continuous walls are often used as the enclosure structure. The interval shield tunnel usually needs to pass through the ground-connected walls on both sides of the station when it passes under the station at a close distance. If glass fiber reinforcement is reserved, the shield can be easily broken. However, the construction speed of my country's subway is fast, and the line network is adjusted from time to time. The interval tunnel often needs to pass through the reinforced concrete ground-connected wall without reservation. According to incomplete statistics, in the current rail transit construction in Suzhou, Guangzhou, Hangzhou, Tianjin, Wuxi and other cities, the interval tunnel has encountered the situation of passing through the reinforced concrete ground-connected wall, and with the densification of the rail transit network, this situation will occur more and more frequently. The commonly used crossing method is to construct a vertical shaft from the ground, and use horizontal freezing, grouting and other methods to reinforce the soil at the bottom of the station in the vertical shaft, and then use the mining method to manually clear the obstacles. The manual obstacle removal method has high cost, long construction period and high risk. If the shield is used to directly cut through the reinforced concrete, it can effectively shorten the construction period, save costs, improve engineering safety, etc., and has significant economic and social benefits.

[0003] The technical bottleneck of shield tunneling for directly cutting reinforced concrete ground-anchored walls lies in the inadaptability of the cutter to the cutting material. Shield cutters are mainly designed for cutting natural rock and soil, while reinforced concrete is artificially cast from two materials with very different properties, and its material properties are significantly different from those of natural rock and soil. Shield tunneling for cutting reinforced concrete can easily lead to problems such as the cutterhead getting stuck, excessive vibration and impact, and excessive steel and concrete slag clogging the spiral excavator. At present, the technology of shield tunneling for directly cutting reinforced concrete piles is relatively mature, but the engineering risk is relatively high. The cutting of reinforced concrete ground-anchored walls is still in the exploratory stage and is only implemented in very few projects with relatively good construction conditions. Therefore, the core of shield tunneling cutting projects lies in the selection of reasonable cutterhead configuration and excavation parameters to ensure that the shield has the ability to cut reinforced concrete.

[0004] However, there is currently a lack of systematic research on shield cutting reinforced concrete ground-connected walls, and there are few construction methods for shield directly cutting reinforced concrete ground-connected walls across the country. Most of them are inventions that introduce shield cutting pile foundation obstacles or passing under existing station structures. For example, the cutter head configuration of invention CN103670428A can smoothly cut bridge piles, and CN114991790A and CN112983446A can smoothly cut station pile foundations at close range. However, facing the ground-connected wall enclosure structure whose reinforced concrete volume is much larger than the pile foundation, its cutter head torque can only be controlled within 60% of the rated power. Faced with the ground-connected wall enclosure structure whose reinforced concrete volume is much larger than the pile foundation, there is a risk of excessive cutter head torque, excessive tool damage, and the risk of too long steel bars blocking the screw machine. Invention patent CN112983441A only solves the problem of safety of close-range side-through of existing subway lines from the perspective of monitoring, but cannot solve the problem of reinforced concrete obstacles. Invention CN202310575482.2, based only on construction experience, fails to provide a research method for a shield machine cutting reinforced concrete ground-anchored wall.

[0005] Inventions CN202310839179.9, CN202310359976.7, and CN202311790561.1 provide indoor and field test schemes for shield cutting reinforced concrete ground-connected walls, which intuitively reflect the effect of tool cutting reinforced concrete. However, the labor and material costs of indoor and field test methods are huge, and it is difficult to design and realize the cutting effects and damage mechanisms under various tool configurations and different excavation parameters, and it is difficult to compare various working conditions, so it is difficult to propose a better cutter configuration and better excavation parameters. Summary of the invention

[0006] Purpose of the invention: The purpose of the present invention is to provide a numerical simulation method for shield cutters cutting reinforced concrete ground-connected walls. By changing the number of cutters, their layout and excavation speed, the cutting effects under different working conditions can be provided, thereby obtaining a better cutterhead configuration and excavation parameters. The problem of the difficulty in simulating passive rotation when hob-type cutters cut reinforced concrete is solved, making the numerical model more consistent with the actual cutting effect.

[0007] Technical solution: A numerical simulation method for shield tool cutting reinforced concrete ground-connected wall of the present invention comprises the following steps:

[0008] Step 1: construct a three-dimensional model, including a shield cutterhead model, a tool model, a cutterhead main body model, and a reinforced concrete ground-connected wall model;

[0009] Step 2: Import the 3D model into the software and define the material and section properties;

[0010] Step 3: Divide the three-dimensional model into grids;

[0011] Step 4: Define rigid constraints and binding constraints for the 3D model;

[0012] Step 5: define the interaction for the three-dimensional model;

[0013] Step 6: Create analysis steps;

[0014] Step 7: Set boundary conditions;

[0015] Step 8: Data analysis to achieve numerical simulation of shield tool cutting reinforced concrete ground-anchored wall.

[0016] Furthermore, step 1 specifically includes the following steps:

[0017] Step 1.1, establish a shield cutterhead model, which includes the cutterhead body and the cutter; the cutterhead is divided into rolling cutters and cutting cutters of different sizes; the cutting cutter is welded to the cutterhead and forms a rigid body with the cutterhead. It only rotates with the revolution of the cutterhead, generating tangential force, but cannot generate self-rotation; it is more complicated to establish rolling cutters, which requires the configuration of a cutter box, gasket, cutter shaft and the cutter itself; the cutter box, gasket and cutterhead are welded to form a rigid body, and the roller needs to be connected to the cutter box by the cutter shaft; when the cutterhead rotates, the roller rotates with the revolution of the cutterhead, generating tangential force; when the roller contacts reinforced concrete, the friction force is large enough to meet the self-rotation condition of the roller, and the roller rotates to generate rolling force;

[0018] Step 1.2: Create tools. According to the actual tool size requirements, use SOLIDWORKS software to build rolling tools and cutting tools. When building cutting tools, the size of the blade base needs to be adjusted; when building rolling tools, the size parameters of the blade, the inner diameter of the hob, and the overall thickness of the hob need to be adjusted.

[0019] Step 1.3, build the main model of the cutter head. The main body of the cutter head is used as the carrier for installing the tool. The three-dimensional model needs to be built according to the size of the actual drawing. For cutting tools, no space needs to be reserved. For rolling tools, a tool box needs to be reserved on the main body of the cutter head. After reserving the tool box, build the hob shaft and gaskets on both sides in the tool box to form the main body of the cutter head. When building the model, the tool box reserves gaps in two aspects. On the one hand, a gap is reserved between the hob and the shaft, that is, the thickness of the hob is slightly smaller than the wheelbase of the shaft; on the other hand, a gap is reserved between the shaft and the inner wall of the hob, that is, the diameter of the shaft is slightly smaller than the inner diameter of the hob.

[0020] Step 1.4, assemble the shield cutterhead, and use the face-to-face matching method to install the cutting tool to the corresponding position on the front of the cutterhead to form a rigid connection with the cutterhead; for rolling tools, two matching methods, coaxial and same width, are used. One of the rollers is installed in the reserved tool box position, and the remaining rollers are installed to the corresponding positions through array and rotation operations to form an assembly model of the cutterhead and the rollers, and finally form a shield cutterhead; the subsequent shield cutterhead model can form different shield cutterhead configurations by changing the position of the tool arrangement according to the above steps;

[0021] Step 1.5: Establish a reinforced concrete ground-anchored wall model. Use SOLIDWORKS modeling software to establish concrete and steel bar models respectively according to the actual drawing dimensions, and use concentric circles to assemble the concrete and steel bar groups into a reinforced concrete ground-anchored wall model.

[0022] Furthermore, step 2 is specifically as follows: in the Property module, select the constitutive, material and cross-sectional properties of the cutterhead body, tool, concrete and steel bar in the model in turn; the cutterhead body and tool use the rigid body constitutive model, and the cross-sectional property is a homogeneous entity; the concrete uses the extended Drucker-Prager constitutive model, and the cross-sectional property is a homogeneous entity; the steel bar uses the Johnson-Cook constitutive model, and the cross-sectional property is a homogeneous entity.

[0023] Furthermore, step 3 specifically includes the following steps:

[0024] Step 3.1, meshing. In the Mesh module, mesh the various parts of the model. The cutter body and the cutter are meshed using the free meshing technology, and the unit type is selected as C3D10M tetrahedral mesh. The steel bars and concrete are meshed using the structured meshing technology, and the unit type is selected as C3D8R hexahedral mesh. To simulate the failure behavior of steel bars and concrete, turn on the Element deletion option in the unit control.

[0025] Step 3.2, assemble the whole model. In the Assembly module, assemble the components of each model into a whole. According to the actual situation, place the reinforced concrete ground-connected wall directly in front of the cutterhead.

[0026] Furthermore, step 4 specifically includes the following steps:

[0027] Step 4.1, define rigid constraints. Define rigid constraints in the Interaction module. Perform rigid body constraints on the cutter head and the cutter respectively. The specific steps are as follows:

[0028] Step 4.1.1, define the cutter head main body constraint. The cutter head constraint is a rigid body constraint. First, create a reference point 1 at the geometric center of the cutter head. Then, select Create Constraint in the Constraint Manager, select Rigid Body as the type, specify the region as the entire cutter head, and select the created reference point 1 as the reference point. This completes the constraint operation of the cutter head main body.

[0029] Step 4.1.2, define tool constraints. The tool constraints are rigid body constraints. First, create a reference point 2 at the geometric center of the hob. Then, select Create Constraint in the Constraint Manager, select Rigid Body as the type, specify the entire hob as the Region, and select the already created reference point 2 as the Reference Point. Complete the definition. If the cutting tool is welded on the cutter head, there is no need to define a reference point.

[0030] Step 4.2, define binding constraints. The definition of binding TIE constraints is carried out in the Interaction module. First, create surface sets for the outer surface of the steel bar surface steel and the inner surface of the concrete surface concrete respectively. Then, select Create Constraint in the Constraint Manager, select Tie Binding as the type, select the established outer surface of the steel bar surface steel as the main surface, select the established inner surface of the concrete surface concrete as the slave surface, select surface to surface as the discrete method, and complete the definition.

[0031] Furthermore, step 5 specifically includes the following steps:

[0032] Step 5.1, define contact properties. The definition of contact properties is carried out in the Interaction module. First, create the interaction properties between the tool and the reinforced concrete. Select Create in the Interaction Property Manager, select General Contact as the type, and name it rigid-rein. Secondly, add normal behavior in the mechanical behavior options, and select "hard" contact for pressure transmission; then add tangential behavior, select penalty function for friction equation, and select 0.3 for friction coefficient to complete the definition;

[0033] Create the interaction between the hob and the cutter box. Select Create in the Interaction Property Manager, select Surface to Surface Contact, rigid-rigid for the type, then add normal behavior in the mechanical behavior options, select "hard" contact for pressure transfer; finally, add tangential behavior, select penalty function for the friction equation, and select 0.2 for the friction coefficient to complete the definition;

[0034] Step 5.2, define contact. The contact is defined in the Interaction module. The surface cutter of the tool outer surface and the surface rein of the mesh unit to be cut of the reinforced concrete ground-connected wall are used to establish a surface set to prepare for the subsequent contact operations of each component.

[0035] First, create the contact between the cutter and the reinforced concrete. Select Create in the Interaction Manager, select General Contact as the type, select the already created rigid-rein as the contact attribute, select the surface cutter set of the outer surface of the cutter as the first surface, select the surface rein set of the ground wall as the second surface, and set the hob surface as the main surface; secondly, in the Interaction Manager, create the contact between the hob and the tool box, select Surface Contact as the type, select the already created rigid-rigid as the contact attribute, select the inner surface of the hob as the first surface, select the tool shaft surface as the second surface, select the "penalty" contact method as the constraint equation, select Finite Slip as the slip formula, and finally complete the definition.

[0036] Furthermore, step 6 is specifically as follows: setting boundary conditions is performed in the Load module, and boundary conditions are set for the reinforced concrete ground-connected wall and the cutterhead theme respectively.

[0037] Furthermore, step 7 specifically includes the following steps:

[0038] Step 7.1, set the boundary conditions of the reinforced concrete ground-connected wall. In the Boundary Condition Manager, select Create Boundary Condition, select Symmetric / Antisymmetric / Asymmetric as the type, and select the four sides and one bottom of the ground-connected wall as the area.

[0039] Step 7.2, set the boundary conditions of the shield cutter head. In the Boundary Condition Manager, select Create Boundary Condition, select Speed / Acceleration as the Type, select the reference point 1 of the cutter head as the Area, and enter the propulsion speed V and the revolution speed VR of the cutter head. Complete the definition.

[0040] The present invention also discloses a computer device, comprising a memory, a processor and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the method of the present invention.

[0041] The present invention also discloses a computer-readable storage medium on which a computer program / instruction is stored. When the computer program / instruction is executed by a processor, the steps of the method of the present invention are implemented.

[0042] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages:

[0043] 1) The problem of difficulty in simulating passive rotation when hob-type tools cut reinforced concrete is solved, making the numerical model more consistent with the actual cutting effect.

[0044] 2) By changing the number of cutters, their layout and excavation speed, the cutting effects under different working conditions can be provided, thereby obtaining the optimal cutterhead configuration and excavation parameters.

[0045] 3) It saves the labor and material costs required for indoor or field tests and is repeatable. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 Numerical simulation step diagram;

[0047] Figure 2 Tool model diagram;

[0048] Figure 3 Schematic diagram of the reserved knife box on the knife disc body;

[0049] Figure 4 The main model of the cutter head;

[0050] Figure 5 Schematic diagram of shield cutterhead;

[0051] Figure 6 Establish a schematic diagram of reinforced concrete ground-connected wall;

[0052] Figure 7 Assembly simulation model;

[0053] Figure 8 Define the rigid constraint diagram;

[0054] Fig. 9 Schematic diagram of steel and concrete surface assembly;

[0055] Fig.10 Schematic diagram of the selection of the cutter and reinforced concrete mesh surface;

[0056] Fig.11 Comparative analysis chart of simulation load results and test data;

[0057] Fig.12 Schematic diagram of reinforced concrete cutting effect. DETAILED DESCRIPTION

[0058] The technical solution of the present invention is further described below in conjunction with the accompanying drawings.

[0059] A numerical simulation method for shield tool cutting reinforced concrete ground-connected wall was invented. Figure 1 As shown, the following steps are included:

[0060] Step 1: construct a three-dimensional model, including a shield cutterhead model, a tool model, a cutterhead main body model, and a reinforced concrete ground-connected wall model;

[0061] Step 2: Import the 3D model into the software and define the material and section properties;

[0062] Step 3: Divide the three-dimensional model into grids;

[0063] Step 4: Define rigid constraints and binding constraints for the 3D model;

[0064] Step 5: define the interaction for the three-dimensional model;

[0065] Step 6: Create analysis steps;

[0066] Step 7: Set boundary conditions;

[0067] Step 8: Data analysis to achieve numerical simulation of shield tool cutting reinforced concrete ground-anchored wall.

[0068] 1. According to the actual tool size requirements, such as Figure 2 As shown in the figure, SOLIDWORKS software is used to build rolling tools and cutting tools. Among them, when building cutting tools, more attention should be paid to the size of the blade base to facilitate subsequent assembly. When building rolling tools, more attention should be paid to the size parameters including the blade, the inner diameter of the hob, and the overall thickness of the hob.

[0069] 2. After the tool is created, use SOLIDWORKS software to create a 3D model of the tool disc body according to the actual size, such as Figure 3 As shown in the figure, a tool box is reserved for the rolling tool on the cutter body, and then the hob cutter shaft and the gaskets on both sides are built in the tool box to form the cutter body, see Figure 4 It should be noted that in order to ensure that the hob can passively rotate in the subsequent simulation, the cutter box needs to reserve gaps (<1mm) in two aspects when building the model: 1) a gap is reserved between the hob and the cutter shaft, that is, the hob thickness is slightly smaller than the cutter shaft distance 2) a gap is reserved between the cutter shaft and the inner wall of the hob, that is, the cutter shaft diameter is slightly smaller than the inner diameter of the hob.

[0070] 3. If Figure 5As shown in the figure, the cutting tool is installed at the corresponding position on the front of the cutter disc by face-to-face matching, forming a rigid connection with the cutter disc. Then, one of the hobs is installed in the reserved position of the cutter box by using the "coaxial" and "same width" matching methods, and the remaining hobs are installed in the corresponding positions through operations such as "array" and "rotation", forming an assembly model of the cutter disc and the hobs, and finally forming a shield cutter disc. The subsequent shield cutter disc model can form different cutter disc configurations by changing the position of the tool arrangement according to the above steps.

[0071] 4. If Figure 6 As shown, using SOLIDWORKS modeling software, according to the actual drawing size, the concrete and steel bar models are established respectively, and the concrete and steel bar groups are assembled into a reinforced concrete ground-connected wall model by using concentric circles. After the above modeling is completed, the 3D model is imported into ABAQUS finite element software for subsequent definition.

[0072] 5. In the Property module, select the constitutive, material and section properties of the cutterhead, cutter, concrete and steel in the model. The cutterhead and cutter use the rigid body constitutive model, and the section property is a homogeneous entity. For detailed material parameter values, please refer to Table 1; the concrete uses the extended Drucker-Prager constitutive model, and the section property is a homogeneous entity. For detailed material parameter values, please refer to Table 2; the steel bar uses the Johnson-Cook constitutive model, and the section property is a homogeneous entity. For detailed material parameter values, please refer to Table 3.

[0073] Table 1 Material parameter values ​​of the cutter head body and the cutter

[0074]

[0075] Table 2 Concrete material parameter values

[0076]

[0077] Table 3 Rebar material parameter values

[0078]

[0079] 6. First, in the Mesh module, use the free meshing technology for the cutter head and cutter in the model, and select C3D10M (tetrahedral mesh) as the unit type. Then, use the structured meshing technology for the steel bars and concrete, and select C3D8R (hexahedral mesh) as the unit type. To simulate the failure behavior of steel bars and concrete, turn on the Element deletion option in the unit control. Finally, in the Assembly module, assemble the components of each model into a whole. According to the actual situation, place the reinforced concrete ground wall in front of the cutter head, such as Figure 7 shown.

[0080] 7. If Figure 8 As shown, in the Interaction module, rigid body constraints are applied to the cutterhead body and the tool. First, create a reference point 1 at the geometric center of the cutterhead. Next, select Create Constraint in the Constraint Manager, select Rigid Body as the type, specify the entire cutterhead as the region, and select the already created reference point 1 as the reference point to complete the constraint operation of the cutterhead body. Then select any hob and create a reference point 2 at its geometric center. Finally, select Create Constraint in the Constraint Manager, select Rigid Body as the type, specify the entire hob as the region, and select the already created reference point 2 as the reference point to complete the definition.

[0081] 8. If Fig. 9 As shown in the figure, in the Interaction module, define the TIE constraint for the steel and concrete. First, create a surface set for the outer surface of the steel and the inner surface of the concrete, then select Create Constraint in the Constraint Manager, select Tie for the type, select the established outer surface of the steel as the main surface, select the established inner surface of the concrete as the secondary surface, select surface to surface for the discrete method, and complete the definition.

[0082] 9. Define the contact properties for the tool and reinforced concrete in the Interaction module. First, select Create in the Interaction Property Manager, select General Contact as the type, and name it rigid-rein. Secondly, add normal behavior in the mechanical behavior options, and select "hard" contact for pressure transfer; then add tangential behavior, select penalty function for the friction equation, and use 0.3 as the friction coefficient to complete the definition. Then, create the interaction between the hob and the tool box, select Create in the Interaction Property Manager, select Surface to Surface Contact, rigid-rigid as the type. Then add normal behavior in the mechanical behavior options, and select "hard" contact for pressure transfer. Finally, add tangential behavior, select penalty function for the friction equation, and use 0.2 as the friction coefficient to complete the definition.

[0083] 10. Fig.10 As shown, define "contact" for the cutter and reinforced concrete. First, establish a surface set for the outer surface of the cutter (surfacecutter) and the mesh unit to be cut of the reinforced concrete ground-connected wall (surface rein) to prepare for the "contact" operation of the subsequent components. Secondly, create the contact between the cutter and the reinforced concrete. Select Create in the Interaction Manager, select General Contact (Explicit) for Type, select the already created rigid-rein for Contact Properties, select the outer surface set of the cutter (surface cutter) for the first surface, select the ground-connected wall (surface rein) for the second surface, and set the hob surface as the main surface. Then, in the Interaction Manager, create "contact" between the hob and the tool box (cutting tools have no inner surface, so no setting is required), select Surface Contact (Explicit) for Type, select the already created rigid-rigid for Contact Properties, select the inner surface of the hob for the first surface, select the surface of the cutter shaft for the second surface, select the "penalty" contact method for the constraint equation, and select finite slip for the slip formula to complete the definition. Finally, in the Step module, create analysis step step1, select "Dynamic, Explicit" as the type, enter the time history length, and turn on the "Geometry Large Deformation" option.

[0084] 11. First, in the boundary condition Load module, select the boundary condition manager to create a boundary condition, select symmetric / antisymmetric / asymmetric as the type, select the four sides and one bottom of the ground-connected wall in the area, and complete the definition of the boundary condition of the reinforced concrete ground-connected wall. Then, select Create Boundary Condition in the Boundary Condition Manager, select Speed / Acceleration as the type, select the reference point 1 of the cutterhead in the area, enter the cutterhead's propulsion speed V and revolution speed VR, and complete the shield cutterhead definition.

[0085] 12. After completing the above steps, the numerical simulation of shield cutting reinforced concrete can be realized in ABAQUS finite element software. Fig.11 , 12 As shown in the figure, the failure mode of reinforced concrete can be directly reflected, and detailed data including the failure mechanism of reinforced concrete, failure stress distribution and cutter head load can be obtained. Subsequently, the design of different working conditions can be realized by changing the position and distribution of the cutter, the propulsion speed and revolution speed of the cutter head, and the result data under different working conditions can be obtained by repeating the above steps.

Claims

1. A numerical simulation method for shield tool cutting reinforced concrete ground-connected wall, characterized in that: The steps include: Step 1: construct a three-dimensional model, including a shield cutterhead model, a tool model, a cutterhead main body model, and a reinforced concrete ground-connected wall model; Step 2: Import the 3D model into the software and define the material and section properties; Step 3: Divide the three-dimensional model into grids; Step 4: Define rigid constraints and binding constraints for the 3D model; Step 4 specifically includes the following steps: Step 4.1, define rigid constraints. Define rigid constraints in the Interaction module. Perform rigid body constraints on the cutter head and the cutter respectively. The specific steps are as follows: Step 4.1.1, define the cutter head main body constraint. The cutter head constraint is a rigid body constraint. First, create a reference point 1 at the geometric center of the cutter head. Then, select Create Constraint in the Constraint Manager, select Rigid Body as the type, specify the region as the entire cutter head, and select the created reference point 1 as the reference point. This completes the constraint operation of the cutter head main body. Step 4.1.2, define tool constraints. The tool constraints are rigid body constraints. First, create a reference point 2 at the geometric center of the hob. Then, select Create Constraint in the Constraint Manager, select Rigid Body as the type, specify the entire hob as the Region, and select the already created reference point 2 as the Reference Point. Complete the definition. If the cutting tool is welded on the cutter head, there is no need to define a reference point. Step 4.2, define the binding constraint. The definition of the binding TIE constraint is carried out in the Interaction module. First, create a surface set for the outer surface of the steel bar surface steel and the inner surface of the concrete surface concrete. Then, select Create Constraint in the Constraint Manager, select Tie Binding as the type, select the established outer surface of the steel bar surface steel as the main surface, select the established inner surface of the concrete surface concrete as the secondary surface, select the surface to surface contact as the discrete method, and complete the definition. Step 5: define the interaction for the three-dimensional model; Step 6: Create analysis steps; Step 7: Set boundary conditions; Step 8: Data analysis to achieve numerical simulation of shield tool cutting reinforced concrete ground-anchored wall.

2. A numerical simulation method for shield tool cutting reinforced concrete ground-connected wall according to claim 1, characterized in that: Step 1 specifically includes the following steps: Step 1.1, establish a shield cutterhead model, which includes the cutterhead body and the cutter; the cutterhead is divided into rolling cutters and cutting cutters of different sizes; the cutting cutter is welded to the cutterhead and forms a rigid body with the cutterhead. It only rotates with the revolution of the cutterhead, generating tangential force, but cannot generate self-rotation; it is more complicated to establish rolling cutters, which requires the configuration of a cutter box, gasket, cutter shaft and the cutter itself; the cutter box, gasket and cutterhead are welded to form a rigid body, and the roller needs to be connected to the cutter box by the cutter shaft; when the cutterhead rotates, the roller rotates with the revolution of the cutterhead, generating tangential force; when the roller contacts reinforced concrete, the friction force is large enough to meet the self-rotation condition of the roller, and the roller rotates to generate rolling force; Step 1.2: Create tools. According to the actual tool size requirements, use SOLIDWORKS software to build rolling tools and cutting tools. When building cutting tools, the size of the blade base needs to be adjusted; when building rolling tools, the size parameters of the blade, the inner diameter of the hob, and the overall thickness of the hob need to be adjusted. Step 1.3, build the main model of the cutter head. The main body of the cutter head is used as the carrier for installing the tool. The three-dimensional model needs to be built according to the size of the actual drawing. For cutting tools, no space needs to be reserved. For rolling tools, a tool box needs to be reserved on the main body of the cutter head. After reserving the tool box, build the hob shaft and gaskets on both sides in the tool box to form the main body of the cutter head. When building the model, the tool box reserves gaps in two aspects. On the one hand, a gap is reserved between the hob and the shaft, that is, the thickness of the hob is slightly smaller than the wheelbase of the shaft; on the other hand, a gap is reserved between the shaft and the inner wall of the hob, that is, the diameter of the shaft is slightly smaller than the inner diameter of the hob. Step 1.4, assemble the shield cutterhead, and use the face-to-face matching method to install the cutting tool to the corresponding position on the front of the cutterhead to form a rigid connection with the cutterhead; for rolling tools, two matching methods, coaxial and same width, are used. One of the rollers is installed in the reserved tool box position, and the remaining rollers are installed to the corresponding positions through array and rotation operations to form an assembly model of the cutterhead and the rollers, and finally form a shield cutterhead; the subsequent shield cutterhead model can form different shield cutterhead configurations by changing the position of the tool arrangement according to the above steps; Step 1.5: Establish a reinforced concrete ground-anchored wall model. Use SOLIDWORKS modeling software to establish concrete and steel bar models respectively according to the actual drawing dimensions, and use concentric circles to assemble the concrete and steel bar groups into a reinforced concrete ground-anchored wall model.

3. A numerical simulation method for shield tool cutting reinforced concrete ground-connected wall according to claim 1, characterized in that: Step 2 is as follows: In the Property module, select the constitutive, material and cross-sectional properties of the cutterhead body, tool, concrete and steel bars in the model in turn; the cutterhead body and tool use the rigid body constitutive model, and the cross-sectional properties are homogeneous entities; the concrete uses the extended Drucker-Prager constitutive model, and the cross-sectional properties are homogeneous entities; the steel bars use the Johnson-Cook constitutive model, and the cross-sectional properties are homogeneous entities.

4. The numerical simulation method for shield tool cutting reinforced concrete ground-connected wall according to claim 1, characterized in that: Step 3 specifically includes the following steps: Step 3.1, meshing. In the Mesh module, mesh the various parts of the model. The cutter body and the cutter are meshed using the free meshing technology, and the unit type is selected as C3D10M tetrahedral mesh. The steel bars and concrete are meshed using the structured meshing technology, and the unit type is selected as C3D8R hexahedral mesh. To simulate the failure behavior of steel bars and concrete, turn on the Element deletion option in the unit control. Step 3.2, assemble the whole model. In the Assembly module, assemble the components of each model into a whole. According to the actual situation, place the reinforced concrete ground-connected wall directly in front of the cutterhead.

5. The numerical simulation method for shield tool cutting reinforced concrete ground-connected wall according to claim 1, characterized in that: Step 5 specifically includes the following steps: Step 5.1, define contact properties. The definition of contact properties is carried out in the Interaction module. First, create the interaction properties between the tool and the reinforced concrete. Select Create in the Interaction Property Manager, select General Contact as the type, and name it rigid-rein. Secondly, add normal behavior in the mechanical behavior options, and select "hard" contact for pressure transmission; then add tangential behavior, select penalty function for friction equation, and select 0.3 for friction coefficient to complete the definition; Create the interaction between the hob and the cutter box. Select Create in the Interaction Property Manager, select Surface to Surface Contact, rigid-rigid for the type, then add normal behavior in the mechanical behavior options, select "hard" contact for pressure transmission; finally, add tangential behavior, select penalty function for the friction equation, and select 0.2 for the friction coefficient to complete the definition; Step 5.2, define contact. The contact is defined in the Interaction module. The surface cutter of the tool outer surface and the surface rein of the mesh unit to be cut of the reinforced concrete ground-connected wall are used to establish a surface set to prepare for the subsequent contact operations of each component. First, create the contact between the cutter and the reinforced concrete. Select Create in the Interaction Manager, select General Contact as the type, select the already created Rigid-Rein as the contact attribute, select the surface cutter set of the outer surface of the cutter as the first surface, select the surface rein set of the ground-connected wall as the second surface, and set the surface of the hob as the main surface; secondly, in the Interaction Manager, create the contact between the hob and the tool box, select Surface Contact as the type, select the already created Rigid-Rigid as the contact attribute, select the inner surface of the hob as the first surface, select the tool shaft surface as the second surface, select the "Penalty" contact method for the constraint equation, select Finite Slip as the slip formula, and finally complete the definition.

6. The numerical simulation method for shield tool cutting reinforced concrete ground-connected wall according to claim 1, characterized in that: Step 6 is as follows: setting boundary conditions is performed in the Load module, and boundary conditions are set for the reinforced concrete ground-connected wall and the cutterhead theme respectively.

7. The numerical simulation method for shield tool cutting reinforced concrete ground-connected wall according to claim 1, characterized in that: Step 7 specifically includes the following steps: Step 7.1, set the boundary conditions of the reinforced concrete ground-connected wall. In the Boundary Condition Manager, select Create Boundary Condition, select Symmetric / Antisymmetric / Asymmetric as the type, and select the four sides and one bottom of the ground-connected wall as the area. Step 7.2, set the boundary conditions of the shield cutter head. Select Create Boundary Condition in the Boundary Condition Manager, select Speed / Acceleration as the type, select the reference point 1 of the cutter head as the area, enter the propulsion speed V and revolution speed VR of the cutter head, and complete the definition.

8. A computer device comprising a memory, a processor and a computer program stored in the memory, characterized in that: The processor executes the computer program to implement the steps of the method of claim 1.

9. A computer-readable storage medium having a computer program / instruction stored thereon, characterized in that: When the computer program / instructions are executed by a processor, the steps of the method according to claim 1 are implemented.

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