Three-dimensional parameterized simulation calculation method for duct piece structure of heading machine

Abstract

The invention relates to a tunneling machine duct piece design technology, discloses a three-dimensional parameterization simulation calculation method for a tunneling machine duct piece structure, and solves the problems of complex manual modeling, low efficiency, time-consuming calculation and the like in an existing tunneling machine duct piece modeling and simulation scheme based on a simplified three-dimensional model. The method comprises the following steps: calling a model initialization command set to initialize a modeling environment, and calling a basic parameter command set to establish a basic parameter system; the load analysis command set is called to calculate and process the formation pressure borne by the duct piece, and the load borne by the duct piece is obtained; calling the structure modeling command set to construct and obtain a heading machine three-dimensional segment calculation model comprising nodes, beam units and spring units; calling a calculation analysis command set to carry out automatic simulation solving processing on the three-dimensional segment calculation model, and automatically outputting a calculation result; and obtaining a calculation result, calling a reinforcement analysis module and a structure calculation report module, and automatically obtaining recommended segment reinforcement information and a structure calculation report.

Description

Technical Field

[0001] The invention relates to a tunnel boring machine segment design technology, and in particular to a three-dimensional parameterized simulation calculation method for a tunnel boring machine segment structure. Background Art

[0002] In underground engineering construction, shield construction technology is widely used in underground engineering projects under various complex geological conditions because of its low impact on the environment and high construction efficiency. As the core structure in shield construction, the design quality of the tunnel boring machine segments is directly related to the overall stability and durability of the tunnel. The tunnel boring machine segments are generally made of high-strength reinforced concrete materials and assembled in sections to form a tunnel lining structure. Their stress performance, deformation resistance, durability and other characteristics are crucial to the safety of the tunnel. Faced with complex and changeable geological conditions, accurately simulating and evaluating the mechanical behavior of the segments under different stress conditions is an important part of the design that cannot be ignored. Therefore, the research on the design and simulation analysis of tunnel boring machine segments has become a hot topic in the current academic and engineering circles.

[0003] Existing modeling and simulation schemes for tunnel boring machine segments are mainly divided into two types: two-dimensional models and three-dimensional models. Among them, although the two-dimensional model has a fast calculation speed, it is difficult to accurately reflect the actual stress state of the segment; the three-dimensional model is divided into a refined three-dimensional model and a simplified three-dimensional model. Among them, although the refined three-dimensional model has high accuracy, the modeling process is complex, there are many parameters, the calculation cost is high, and it is difficult to converge; in contrast, the simplified three-dimensional model simplifies the tunnel boring machine segment structure into beam units, and uses spring units to simulate the connection between the segments and the interaction between the segments and the formation. Through reasonable simplification and parameterization settings, it can ensure the calculation accuracy, and has the characteristics of high calculation efficiency and flexible and adjustable parameters. Therefore, the simplified three-dimensional model is currently widely used in the modeling and simulation analysis of tunnel boring machine segments.

[0004] However, in the traditional technology, the modeling and simulation scheme of the tunnel boring machine segment based on the simplified three-dimensional model mainly relies on manual definition and construction of the model to simulate the complex mechanical interaction between the tunnel boring machine segment structure and the stratum. The specific implementation process includes the following: 1. Artificial parameter definition and modeling In this process, researchers manually defined various parameters of the simplified 3D model based on the actual needs of the shield tunnel project, including the stiffness characteristics of the segment structure, the spring stiffness between the stratum and the segment, and the joint characteristics between the segment rings. These parameters are usually set in combination with engineering experience, geological survey data and design standards. The modeling process is usually carried out through professional modeling software and requires gradual adjustment and verification. The steps are as follows: (1) Input structural parameters: define the geometric dimensions, material properties and cross-sectional properties of the segment.

[0005] (2) Setting spring units: According to the elastic modulus of the stratum and the soil properties, the stiffness parameters of each spring unit are set to simulate the interaction between the segment and the surrounding strata.

[0006] (3) Determine boundary conditions: Set the boundary conditions and external loads of the model, such as formation stress, groundwater pressure, and construction disturbance effects.

[0007] (4) Calibration model: Through multiple simulations and adjustments, the model parameters are optimized so that the simulation results are consistent with the expected engineering data or experimental results.

[0008] 2. Segmented beam elements and local refinement models In this process, in order to improve the accuracy of the model, the tunnel boring machine segment is usually discretized into multiple beam units, which are connected to springs of different stiffness to form a parameterized finite element model. For complex working conditions, such as uneven strata or asymmetric load conditions, local areas may be further refined to capture stress concentration and deformation behavior, which is suitable for analyzing local stress characteristics and sensitive areas.

[0009] 3. Static and dynamic simulation analysis In this process, based on the simplified three-dimensional model constructed, the researchers used numerical simulation tools to analyze the structural behavior of the shield tunnel in different construction stages and long-term operation. This includes static analysis (such as structural stability and ground deformation) and dynamic analysis (such as construction disturbance effects and ground consolidation effects), which are often used to evaluate ground settlement, segment stress distribution, structural stability, etc., and assist engineering design and construction decisions.

[0010] The defects of the above-mentioned traditional technology based on simplified three-dimensional model of tunnel boring machine segment modeling and simulation scheme include: (1) Manual modeling is difficult and the operation is cumbersome The entire modeling process requires a lot of manual intervention, especially in the process of setting parameters and modeling. Researchers need to comprehensively consider complex geological conditions, structural characteristics and construction conditions. Manually inputting and adjusting each parameter calculation formula is not only time-consuming, but also easy to introduce human errors, resulting in inaccurate or unstable models. Especially in projects with complex strata and significant structural nonlinearity, manual modeling is difficult to achieve fast and accurate simulation.

[0011] (2) Parameter adjustment is complex and inefficient The parameterization process of the model involves a large number of interrelated variables, such as segment stiffness, interface stiffness characteristics, and formation spring stiffness. Researchers need to gradually optimize these parameters to ensure that the model can reasonably reflect the stress and deformation characteristics in actual engineering. However, the parameter setting and model verification process is very time-consuming, especially when facing long-distance or deep-buried tunnel projects, which is inefficient and difficult to meet the needs of rapid engineering response.

[0012] (3) High computational complexity and high resource consumption The setting of multiple simplified 3D model units and the interaction between complex boundary conditions and strata lead to complex simulation calculations and long calculation time, especially when high-precision simulation or multi-field coupling analysis is required, which consumes huge computing resources. This also limits the application scope of simulation methods based on simplified 3D models in actual engineering, especially in situations where rapid adjustment of plans or real-time construction monitoring are required, which makes it difficult to meet the needs of engineering progress and optimized design.

[0013] In summary, the existing modeling and simulation schemes for tunnel boring machine segments based on simplified three-dimensional models have problems such as difficulty in manual modeling, complex parameter adjustment, low efficiency, and high overall simulation calculation complexity, which makes it difficult to meet the actual needs of rapid engineering decision-making and optimized design. These problems highlight the limitations of the model in practical applications, and there is an urgent need to improve modeling and simulation technology to improve efficiency and accuracy. Summary of the invention

[0014] The technical problem to be solved by the present invention is to propose a three-dimensional parametric simulation calculation method for a tunnel boring machine segment structure, so as to solve the problems of complex manual modeling, low efficiency and time-consuming calculation in the existing tunnel boring machine segment modeling and simulation scheme based on a simplified three-dimensional model.

[0015] The technical solution adopted by the present invention to solve the above technical problems is: A three-dimensional parametric simulation calculation method for a tunnel boring machine segment structure comprises the following steps: S1. Calling the model initialization command set to initialize the modeling environment, and calling the basic parameter command set to establish a basic parameter system including material attribute parameters, geometric feature parameters and formation characteristic parameters; S2. Calling a load analysis command set to calculate the formation pressure on the segment and obtain the load on the segment; S3, calling the structural modeling command set to construct a three-dimensional segment calculation model of the tunnel boring machine including nodes, beam units and spring units; S4, calling the calculation and analysis command set to automatically simulate and solve the three-dimensional segment calculation model of the tunnel boring machine, and automatically output the calculation results; S5. Obtain calculation results, call the reinforcement analysis module and the structural calculation report module, and automatically obtain the recommended tunnel boring machine segment reinforcement information and structural calculation report.

[0016] Furthermore, in step S1, the calling of the model initialization command set to initialize the modeling environment includes: Clear historical data and define the current simulation file and title, initialize the simulation environment, set the international unit system and convert to the cylindrical coordinate system.

[0017] Furthermore, in step S1, the calling of the basic parameter command set to establish a basic parameter system including material property parameters, geometric characteristic parameters and formation characteristic parameters includes: Call the material parameter definition function command set to define the segment elastic modulus, density and Poisson's ratio parameters; Call the geometric feature parameter definition command set to define the segment outer diameter, ring width, wall thickness, number of segment blocks, total number of inter-ring bolts, capping block offset angle, capping block inner ring size, adjacent block inner ring size, inter-ring bolt radial and tangential stiffness, and annular bolt bending stiffness parameters; The formation characteristic parameter definition command set is called to define the segment burial depth, groundwater level depth, ground overload, surrounding rock weight, surrounding rock grade and recommended values ​​of geotechnical design parameters.

[0018] Furthermore, in step S2, the calling of the load analysis command set to calculate the formation pressure on the segment to obtain the load on the segment includes: Obtain the input geometric characteristic parameters and stratum characteristic parameters, call the load calculation command set, and calculate the vertical earth pressure, lateral earth pressure, lateral water pressure and stratum resistance load; Obtain global coordinate positioning data, call the global coordinate conversion command set, transform local load components from the local coordinate system to the global coordinate system, obtain global load component values, and make the load distribution conform to the actual stress conditions of the segment.

[0019] Furthermore, in step S3, the calling of the structural modeling command set to construct a three-dimensional segment calculation model of the roadheader including nodes, beam units and spring units includes: Obtain the input segment geometry parameters, call the node generation command set to automatically generate node coordinates and establish nodes; Obtain the input material parameters, call the beam unit generation command set, and assign corresponding parameters to the unit properties to establish the beam unit for simulating the segment structure; Call the segment annular and inter-annular generation command set to create annular and inter-annular spring units connected to the beam unit, use the inter-annular radial spring unit and the inter-annular tangential spring unit to simulate the tangential and radial performance of the inter-annular bolts, and use the annular bending spring unit to simulate the annular bending performance of the annular bolts; Obtain the input soil layer parameters, call the command set for generating foundation springs, and generate foundation springs connected to the beam unit nodes for simulating the interaction between the pipe segment and the soil layer; Obtain the calculated global load component values, call the load application command set, and apply the load to the beam element nodes; Call the constraint addition command set to simulate the constraint effect of the stratum on the tunnel boring machine segment by constraining the horizontal and vertical displacements of the stratum spring nodes. By constraining the vertical displacement of the highest node of the beam unit, ensure that the top node of the segment is only affected by the vertical earth pressure.

[0020] Furthermore, in step S4, the calling of the calculation and analysis command set to automatically simulate and solve the three-dimensional segment calculation model of the tunnel boring machine and automatically output the calculation results includes: Enter the solution module and set the simulation solution type through static analysis to perform static analysis; Control the nonlinear analysis through load step and sub-step settings; Call the criterion command set to set the convergence criterion and start iterative calculation; Obtain the calculation results of the beam unit nodes and extract and process the displacement and internal force data; Call the post-processing visualization command set to obtain displacement and internal force data, and automatically output the internal force cloud diagram including the bending moment, shear force, axial force of the segment structure and the deformed structure.

[0021] Furthermore, the control processing of the nonlinear analysis by setting the load step and sub-step includes: Define the number of substeps in a load step to control the load application rate; set the time step increment to ensure the stability of the calculation process; adjust the load increment size to optimize the iterative calculation efficiency.

[0022] Furthermore, the setting process of the convergence criterion includes: Set convergence criteria for forces, displacements, moments, and rotations; define tolerances; and adjust convergence parameters.

[0023] Furthermore, the iterative calculation includes: optimizing the iteration strategy during the iteration process; the optimization of the iteration strategy includes: improving the stability of the solution by activating the linear search function; handling complex nonlinear problems by increasing the maximum number of equilibrium iterations; and achieving adaptive control of the calculation process by adjusting the number of load sub-steps.

[0024] Further, in step S5, the calculation results are obtained, the reinforcement analysis module and the structure calculation report module are called, and the recommended tunnel boring machine segment reinforcement information and the structure calculation report are automatically obtained, including: Obtain the generated displacement and internal force data, call the reinforced concrete reinforcement module to automatically analyze the data, and obtain the tunnel boring machine segment reinforcement data; Obtain model parameters, model displacement and internal force data, cloud map and reinforcement data, call the structural calculation report generation module, and obtain the structural calculation report.

[0025] The beneficial effects of the present invention are: (1) Simplify the modeling process and reduce the complexity of manual operations: The present invention simplifies the process of building a three-dimensional segment calculation model of a tunnel boring machine by introducing an integrated command set and a functional module set into automated modeling. Researchers only need to make a small amount of necessary input, and the system can automatically complete the construction and setting of the model, reducing the number of manual operation steps and complexity, reducing the risk of human errors, and improving the convenience and reliability of modeling.

[0026] (2) Optimize the parameterization process and improve modeling and adjustment efficiency: The present invention adopts optimization algorithm to realize automatic calculation and adjustment of model parameters. Researchers only need to input key design parameters, such as the geometric dimensions of the segments and basic characteristics of the formation. The system will automatically generate spring stiffness, beam unit parameters, etc. through intelligent optimization algorithm, which significantly improves the efficiency of parametric modeling and meets the needs of rapid response and adjustment of the project.

[0027] (3) Improve computing efficiency and reduce resource consumption: The present invention reduces the number of iterations of nonlinear analysis by optimizing the solution process, improves the simulation calculation speed, realizes fast simulation, saves computing resources and time, and meets the needs of solution adjustment.

[0028] (4) Automatically generate segment internal force results: The present invention can automatically calculate and generate internal force results such as bending moment, shear force and axial force of the segment, avoiding tedious manual calculation and manual operation processes; after the simulation is completed, the system automatically outputs key mechanical indicators to facilitate rapid analysis and evaluation of the structural performance of the tunnel boring machine segment, providing a reliable mechanical basis for engineering design and construction.

[0029] In summary, the present invention will greatly improve the efficiency and accuracy of the parametric modeling and simulation process of the tunnel boring machine segments, and provide more efficient, intelligent and reliable technical support for the design and construction of complex tunnel projects. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1The present invention is a flow chart of the three-dimensional parametric simulation calculation method for the tunnel boring machine segment structure.

[0031] Figure 2 Schematic diagram of the three-dimensional segment calculation model of the tunnel boring machine based on a simplified three-dimensional model.

[0032] Figure 3 It is a diagram of the implementation process of the three-dimensional parametric simulation calculation of the tunnel boring machine segment structure in an embodiment of the present invention.

[0033] Markings in the figure: 1 is the beam unit, 2 is the annular bending spring unit, 3 is the inter-annular radial tangential spring unit, and 4 is the formation spring unit. DETAILED DESCRIPTION

[0034] The present invention aims to provide a three-dimensional parametric simulation calculation method for the segment structure of a tunnel boring machine, so as to solve the problems of complex manual modeling, low efficiency and time-consuming calculation in the existing tunnel boring machine segment modeling and simulation scheme based on simplified three-dimensional models. The core idea is to introduce integrated command sets and functional module sets into automated modeling, so that researchers only need to set a small number of key parameters. The system can quickly build a tunnel boring machine segment structure model by calling various command sets and parameter systems, avoiding repetitive modeling work, thereby improving modeling efficiency; when the segment structure needs to be modified, only the relevant parameters need to be adjusted to achieve batch update of the model, which also improves the modification efficiency of the model; in addition, during the simulation process, the present invention optimizes the solution process, reduces the number of iterations of nonlinear analysis, improves the simulation calculation speed, realizes fast simulation, saves computing resources and time, and meets the needs of scheme adjustment.

[0035] For ease of understanding, the 3D segment calculation model of the tunnel boring machine based on the simplified 3D model is first explained. The 3D segment of the tunnel boring machine is the modeling object, and its specific structural components include: segment capping block, segment adjacent block, segment standard block, segment annular bolts, segment inter-ring bolts, grouting holes, lifting holes, inter-ring gaskets and caulking. The 3D segment calculation model is simplified on this basis, see Figure 2 The segment capping block, segment adjacent block and segment standard block are simulated by beam unit 1, the segment annular bolts are simulated by annular bending spring unit 2, the segment inter-annular bolts are simulated by inter-annular radial tangential spring unit 3, and the action between the segment and the soil is simulated by stratum spring unit 4.

[0036] Among them, beam unit 1 adopts BEAM3 unit, which is mainly used to simulate the bending stiffness of the segment. Its cross-sectional characteristics are usually defined by real constants, and different cross-sectional parameters may be equipped to meet the force requirements under different working conditions; annular bending spring unit 2 adopts COMBIN39 unit, which is connected with the segment beam unit and is used to simulate the bending stiffness of the annular bolt. This unit can accurately reflect the mechanical properties of the annular joint and plays an important role in ensuring the stability of the overall structure; inter-annular radial tangential spring unit 3 adopts COMBIN39 unit, which is used to simulate the radial shear stiffness and tangential shear stiffness of the inter-annular bolt, which is crucial to ensure the connection performance between segment rings; stratum spring unit 4 adopts COMBIN39 unit, which is used to simulate the supporting effect of the stratum on the tunnel boring machine segment. The stiffness parameters of the stratum spring are determined according to the geological conditions and can effectively simulate the interaction between the stratum and the segment.

[0037] The process of the three-dimensional parameterized simulation calculation method for the tunnel boring machine segment structure provided by the present invention is shown in Figure 1 , which realizes fast and accurate parametric modeling and simulation analysis of the tunnel boring machine segment structure by executing the following steps in sequence: S1. Call the model initialization command set to initialize the modeling environment, and call the basic parameter command set to establish a basic parameter system including material property parameters, geometric feature parameters and formation characteristic parameters.

[0038] In this step, the initialization process includes: clearing historical data and defining the current simulation file and title, obtaining current engineering data, initializing the simulation environment, setting the international system of units and converting to a cylindrical coordinate system.

[0039] Calling the basic parameter command set to establish a basic parameter system including material attribute parameters, geometric characteristic parameters and formation characteristic parameters includes: (1) Call the material parameter definition function command set to define parameters such as the elastic modulus, density and Poisson's ratio of the segment.

[0040] (2) Call the geometric feature parameter definition command set to define parameters such as the outer diameter of the segment, ring width, wall thickness, number of segment blocks, total number of inter-ring bolts, capping block offset angle, capping block ring inner size, adjacent block ring inner size, inter-ring bolt radial and tangential stiffness, and annular bolt bending stiffness.

[0041] (3) Call the formation characteristic parameter definition command set to define parameters such as segment burial depth, groundwater level depth, ground overload, surrounding rock weight, surrounding rock grade, and recommended values ​​of geotechnical design parameters.

[0042] S2. Call the load analysis command set to calculate the formation pressure on the segment and obtain the load on the segment.

[0043] In this step, by obtaining the input geometric characteristic parameters and formation characteristic parameters, the load calculation command set is called to calculate the vertical earth pressure, lateral earth pressure, lateral water pressure and formation resistance load; by obtaining the global coordinate positioning data, the global coordinate conversion command set is called to convert the local load components from the local coordinate system to the global coordinate system, and the global load component values ​​are obtained so that the load distribution meets the actual stress conditions of the segment.

[0044] S3. Call the structural modeling command set to construct a three-dimensional segment calculation model of the tunnel boring machine including nodes, beam units and spring units.

[0045] In this step, the specific implementation process of constructing the three-dimensional segment calculation model of the tunnel boring machine is as follows: (1) Obtain the input segment geometry parameters, call the node generation command set, automatically generate node coordinates and establish nodes.

[0046] (2) Obtain the input material parameters, call the beam element generation command set, and assign the corresponding parameters to the element properties to establish the beam element for simulating the segment structure.

[0047] (3) Call the segment annular and inter-annular generation command set to create annular and inter-annular spring units connected to the beam unit. Use the inter-annular radial spring unit and inter-annular tangential spring unit to simulate the tangential and radial properties of the inter-annular bolts. Use the annular bending spring unit to simulate the annular bending properties of the annular bolts.

[0048] (4) Obtain the input soil layer parameters, call the command set to generate foundation springs, and generate foundation springs connected to the beam unit nodes to simulate the interaction between the pipe segment and the soil layer.

[0049] (5) Obtain the calculated global load component values ​​and call the load application command set to apply the load to the beam element nodes.

[0050] (6) Call the constraint addition command set to simulate the constraint effect of the stratum on the tunnel boring machine segment by constraining the horizontal and vertical displacements of the stratum spring nodes. By constraining the vertical displacement of the highest node of the beam unit, it is ensured that the top node of the segment is only affected by the vertical earth pressure, accurately simulating the load distribution of the surface on the top of the segment.

[0051] S4. Call the calculation and analysis command set to automatically simulate and solve the three-dimensional segment calculation model of the tunnel boring machine, and automatically output the calculation results.

[0052] In this step, the specific implementation process of automatic simulation solution processing is as follows: (1) Enter the solution module and set the simulation solution type through static analysis to perform static analysis.

[0053] (2) Control the nonlinear analysis through load step and substep settings, including: defining the number of substeps in the load step to control the load application rate; setting the time step increment to ensure the stability of the calculation process; adjusting the load increment size to optimize the iterative calculation efficiency.

[0054] (3) Call the criterion command set to set the convergence criterion and start the iterative calculation. The setting of the convergence criterion includes: setting the convergence criteria of force, displacement, bending moment and rotation angle; defining the allowable error range to ensure the calculation accuracy; adjusting the convergence parameters to ensure the reliability of the calculation results; optimizing the iteration strategy during the iteration process: improving the stability of the solution by activating the linear search function; handling complex nonlinear problems by increasing the maximum number of equilibrium iterations; and achieving adaptive control of the calculation process by adjusting the number of load sub-steps.

[0055] (4) Obtain the calculation results of the beam unit nodes and extract and process the displacement and internal force data.

[0056] (5) Call the post-processing visualization command set to obtain displacement and internal force data, and automatically output the internal force cloud diagram including the bending moment, shear force, axial force of the segment structure and the deformed structure.

[0057] S5. Obtain the calculation results, call the reinforcement analysis module and the structural calculation report module, and automatically obtain the recommended tunnel boring machine segment reinforcement information and structural calculation report.

[0058] In this step, by obtaining the generated displacement and internal force data, the reinforced concrete reinforcement module is called to automatically analyze the data to obtain the reinforcement data of the tunnel boring machine segment; by obtaining the model parameters, model displacement and internal force data, cloud map and reinforcement data, the structural calculation report generation module is called to obtain the structural calculation report.

[0059] Taking the parametric modeling and simulation of the three-dimensional segment of the tunnel boring machine based on the ANSYS platform as an example, this embodiment adopts the APDL command flow (ANSYS parametric design language) method. First, the material properties, geometric dimensions and load parameters are set through parametric definition, and then nodes and units are automatically generated based on these parameters. The load on the segment is automatically calculated and applied based on these parameters, which can realize the rapid parametric modeling of the tunnel boring machine segment. Finally, by setting iterative calculation control parameters and post-processing commands, the solution of the structural response and the display of the results are completed.

[0060] Since the present embodiment defines the model in a parametric manner and calls a fixed-function command set to perform modeling set simulation, there is no need to repeat the modeling operation, thereby significantly improving the analysis efficiency. Secondly, when the segment parameters need to be modified, only the corresponding input parameters need to be adjusted to quickly complete the new analysis, thereby improving the design optimization efficiency.

[0061] See also Figure 3 The implementation process of the three-dimensional parametric simulation calculation of the tunnel boring machine segment structure in this embodiment is as follows: 1. Initialization settings: Use the / clear command to clear all historical data in the current database to prevent historical data from interfering with the current modeling. Use the / filename command to define the name of the current simulation file, use the / title command to set the analysis title, use the / units,si command to specify the use of the International System of Units (SI), and finally use the csys,1 command to specify the use of the cylindrical coordinate system.

[0062] 2. Call the basic parameter command set to establish the basic parameter system: Segment material property settings: Use The command defines the geometry parameter group, material parameter group and load parameter group to establish the basic parameter system. Set the basic characteristic parameters of the segment material, such as elastic modulus, density and Poisson's ratio. Specifically, use the mp command to specify these material parameters for the segment structure.

[0063] Define the geometric characteristic parameters of the segment and the formation characteristic parameters: define the geometric characteristic parameters of the segment, including outer diameter, ring width, wall thickness, etc.; at the same time, set the formation characteristic parameters, including cover thickness, groundwater depth, surrounding rock weight, etc. These parameters will be stored in the corresponding parameter array for subsequent calculation and analysis.

[0064] 3. Calculation of load on the segment: The vertical earth pressure on the segment is calculated according to the following formula: ; The lateral earth pressure on the segment is calculated according to the following formula: ; ; The lateral water pressure on the segment is calculated according to the following formula: ; ; The vertical water buoyancy on the segment is calculated according to the following formula: ; The formation resistance of the segment is calculated according to the following formula: ; in: is the vertical earth pressure; is the lateral earth pressure on the pipe top; is the lateral earth pressure at the pipe bottom; is the lateral water pressure on the pipe top; is the lateral water pressure at the bottom of the pipe; is water buoyancy; is the formation resistance; is the buried depth of the pipe segment; is the depth of groundwater level; For ground overload; is the outer diameter of the segment; is the floating weight; It is natural heavy; It is water weight; is the lateral pressure coefficient.

[0065] 4. Node and unit creation: According to the geometric characteristic parameters, the node generation command set is called to automatically calculate the node coordinates, and the nodes are created through the n command. And according to the material properties and geometric characteristic parameters, the unit generation command set is called to create units in the following way: Create beam elements using the et,1,beam3 command.

[0066] Use the et,2,combin39 command to create the annular bending spring element.

[0067] Use the et,3,combin39 command to create the formation spring element.

[0068] Use the et,4,combin39 command to create the inter-ring radial spring element.

[0069] Use the et,5,combin39 command to create the inter-annular tangential spring element.

[0070] 5. Load application: First, obtain the load calculation results and convert the load in the cylindrical coordinate system into components in the global coordinate system: Vertical load calculation formula: ; in, It is i The node in k The vertical load on the ring, It is k The bottom pressure of the ring, and is the vertical distance between adjacent nodes.

[0071] Horizontal load calculation formula: ; in, It is i The node in k Horizontal load on the ring, It is k Horizontal pressure of the ring, and is the horizontal distance between adjacent nodes.

[0072] Then, the load application command set is called, in which the f command is mainly used to apply the above-mentioned calculated load components to the corresponding nodes of the beam element.

[0073] 6. Boundary conditions and constraint settings: Call the constraint adding command set. The command set mainly uses the d command to realize the displacement constraint of the stratum elastic pipe node and the vertical displacement of the highest point node of the beam unit to simulate the constraint conditions of the tunnel boring machine segment in the actual engineering. Through the above steps, the three-dimensional calculation model of the tunnel boring machine segment structure has been obtained.

[0074] 7. Automatic simulation solution settings for three-dimensional calculation models: Enter the solution stage, use the / solu command to enter the solver, set ANTYPE, STATIC for static analysis.

[0075] 8. Solving iterative calculation control and executing solution: The implementation of the iterative calculation steps includes: 1. The control of nonlinear analysis is realized through the setting of load steps and substeps. The specific implementation method is as follows: (1) Use the / NSUBST command to define the number of substeps in a load step and control the load application rate.

[0076] (2) Use the TIME command to set the time step increment to ensure the stability of the calculation process.

[0077] (3) Use the ACEL command to adjust the load increment size and optimize the iterative calculation efficiency.

[0078] 2. Establish a convergence criterion control system, the specific implementation method is: (1) Use the SOLVE command in combination with the OUTRES command to set the convergence criteria for force, displacement, moment, and rotation.

[0079] (2) Use the TOLER command to define the allowable error range to ensure calculation accuracy.

[0080] (3) Activate the nonlinear geometry option by adjusting the parameters in the SOLVE command, such as NLGEOM,ON, to ensure the reliability of the calculation results.

[0081] 3. Optimize the iteration strategy, the specific implementation is as follows: (1) Activate the linear search function in the / SOLU module to improve the stability of the solution.

[0082] (2) Increase the maximum number of equilibrium iterations and handle complex nonlinear problems by adjusting the ITER parameters in the / SOLU module.

[0083] (3) Adjust the number of load substeps and realize adaptive control of the calculation process through the SUBST parameter in the / SOLU module.

[0084] 4. By calling the solution and settlement command set, mainly use the solve command to perform iterative calculation and solution until the calculation is completed after convergence.

[0085] 9. Output analysis results: 1. Extraction and visualization of calculation results. The specific implementation methods are as follows: (1) Call the post-processing and internal force extraction command set. The main command of the command set is / POST1. Enter the post-processing module, select specific units and nodes, and use the ETABLE and PLNSOL main commands to extract the key calculation data such as the bending moment, shear force, axial force and deformation of the pipe segment.

[0086] (2) Call the visualization command set. The main command of the command set is the Eplot command. The Eplot command is used to automatically generate the internal force cloud map of the structure. The Eplot command is used to generate visualization results such as the internal force cloud map and the deformation cloud map.

[0087] 2. Data collation and output, the specific implementation method is: (1) Call the data integration command set. The main commands of the command set are and Command to create a calculation data table to store the generated displacement, internal force and other calculation data.

[0088] (2) Call the data processing command set. The main commands of the command set are Command to extract the maximum bending moment, shear force, axial force and displacement data of the segment for subsequent analysis.

[0089] (3) Call the reinforced concrete reinforcement module, import the maximum bending moment, shear force, axial force and displacement data into the module, automatically analyze the data, and obtain the reinforcement data of the tunnel boring machine segment.

[0090] (4) Obtain model parameters, segment displacement and internal force data, cloud map and reinforcement data, and call the structural calculation report generation module. The main commands of the module are and , obtain the structural calculation report.

[0091] Based on the above embodiments, the tunnel boring machine segment structure model can be quickly constructed by calling various command sets and parameter systems. Figure 3It can be seen that in the entire process, except for some key parameters that need to be manually input, the rest are automatically processed by the system, avoiding repetitive modeling work and thus improving modeling efficiency; secondly, when the segment structure needs to be modified, only the relevant parameters need to be adjusted to achieve batch update of the model, which improves the modification efficiency of the model.

[0092] Finally, it should be noted that the above embodiments are only preferred implementations and are not intended to limit the present invention. It should be pointed out that for those skilled in the art, several modifications, equivalent replacements, improvements, etc. can be made without departing from the scope of the present invention and the scope of protection of the claims, and all of these should be included in the protection scope of the present invention.

Claims

1. A three-dimensional parametric simulation calculation method for a tunnel boring machine segment structure, characterized in that: The following steps are involved: S1. Calling the model initialization command set to initialize the modeling environment, and calling the basic parameter command set to establish a basic parameter system including material attribute parameters, geometric feature parameters and formation characteristic parameters; S2. Calling a load analysis command set to calculate the formation pressure on the segment and obtain the load on the segment; S3, calling the structural modeling command set to construct a three-dimensional segment calculation model of the tunnel boring machine including nodes, beam units and spring units; S4, calling the calculation and analysis command set to automatically simulate and solve the three-dimensional segment calculation model of the tunnel boring machine, and automatically output the calculation results; S5. Obtain calculation results, call the reinforcement analysis module and the structural calculation report module, and automatically obtain the recommended tunnel boring machine segment reinforcement information and structural calculation report.

2. A three-dimensional parametric simulation calculation method for a tunnel boring machine segment structure according to claim 1, characterized in that: In step S1, the calling of the model initialization command set to initialize the modeling environment includes: Clear historical data and define the current simulation file and title, initialize the simulation environment, set the international unit system and convert to the cylindrical coordinate system.

3. A three-dimensional parametric simulation calculation method for a tunnel boring machine segment structure according to claim 1, characterized in that: In step S1, the calling of the basic parameter command set to establish a basic parameter system including material property parameters, geometric characteristic parameters and formation characteristic parameters includes: Call the material parameter definition function command set to define the segment elastic modulus, density and Poisson's ratio parameters; Call the geometric feature parameter definition command set to define the segment outer diameter, ring width, wall thickness, number of segment blocks, total number of inter-ring bolts, capping block offset angle, capping block inner ring size, adjacent block inner ring size, inter-ring bolt radial and tangential stiffness, and annular bolt bending stiffness parameters; The formation characteristic parameter definition command set is called to define the segment burial depth, groundwater level depth, ground overload, surrounding rock weight, surrounding rock grade and recommended values ​​of geotechnical design parameters.

4. A three-dimensional parametric simulation calculation method for a tunnel boring machine segment structure according to claim 1, characterized in that: In step S2, the calling of the load analysis command set to calculate the formation pressure on the segment to obtain the load on the segment includes: Obtain the input geometric characteristic parameters and stratum characteristic parameters, call the load calculation command set, and calculate the vertical earth pressure, lateral earth pressure, lateral water pressure and stratum resistance load; Obtain global coordinate positioning data, call the global coordinate conversion command set, transform local load components from the local coordinate system to the global coordinate system, obtain global load component values, and make the load distribution conform to the actual stress conditions of the segment.

5. A three-dimensional parametric simulation calculation method for a tunnel boring machine segment structure according to claim 1, characterized in that: In step S3, the calling of the structural modeling command set to construct a three-dimensional segment calculation model of the roadheader including nodes, beam units and spring units includes: Obtain the input segment geometry parameters, call the node generation command set to automatically generate node coordinates and establish nodes; Obtain the input material parameters, call the beam unit generation command set, and assign corresponding parameters to the unit properties to establish the beam unit for simulating the segment structure; Call the segment annular and inter-annular generation command set to create annular and inter-annular spring units connected to the beam unit, use the inter-annular radial spring unit and the inter-annular tangential spring unit to simulate the tangential and radial performance of the inter-annular bolts, and use the annular bending spring unit to simulate the annular bending performance of the annular bolts; Obtain the input soil layer parameters, call the command set for generating foundation springs, and generate foundation springs connected to the beam unit nodes for simulating the interaction between the pipe segment and the soil layer; Obtain the calculated global load component values, call the load application command set, and apply the load to the beam element nodes; Call the constraint addition command set to simulate the constraint effect of the stratum on the tunnel boring machine segment by constraining the horizontal and vertical displacements of the stratum spring nodes. By constraining the vertical displacement of the highest node of the beam unit, ensure that the top node of the segment is only affected by the vertical earth pressure.

6. A three-dimensional parametric simulation calculation method for a tunnel boring machine segment structure according to claim 1, characterized in that: In step S4, the calling of the calculation and analysis command set automatically simulates and solves the three-dimensional segment calculation model of the tunnel boring machine and automatically outputs the calculation results, including: Enter the solution module and set the simulation solution type through static analysis to perform static analysis; Control the nonlinear analysis through load step and sub-step settings; Call the criterion command set to set the convergence criterion and start iterative calculation; Obtain the calculation results of the beam unit nodes and extract and process the displacement and internal force data; Call the post-processing visualization command set to obtain displacement and internal force data, and automatically output the internal force cloud diagram including the bending moment, shear force, axial force of the segment structure and the deformed structure.

7. A three-dimensional parametric simulation calculation method for a tunnel boring machine segment structure according to claim 6, characterized in that: The control processing of nonlinear analysis through load step and sub-step setting includes: Define the number of substeps in a load step to control the load application rate; set the time step increment to ensure the stability of the calculation process; adjust the load increment size to optimize the iterative calculation efficiency.

8. A three-dimensional parametric simulation calculation method for a tunnel boring machine segment structure according to claim 6, characterized in that: The process of setting the convergence criterion includes: Set convergence criteria for forces, displacements, moments, and rotations; define tolerances; and adjust convergence parameters.

9. A three-dimensional parametric simulation calculation method for a tunnel boring machine segment structure according to claim 6, characterized in that: The iterative calculation includes: optimizing the iteration strategy during the iteration process; the optimization of the iteration strategy includes: improving the stability of the solution by activating the linear search function; dealing with nonlinear problems by increasing the maximum number of equilibrium iterations; and achieving adaptive control of the calculation process by adjusting the number of load sub-steps.

10. A three-dimensional parametric simulation calculation method for a tunnel boring machine segment structure according to claim 1, characterized in that: In step S5, the calculation results are obtained, and the reinforcement analysis module and the structure calculation report module are called to automatically obtain the recommended tunnel boring machine segment reinforcement information and the structure calculation report, including: Obtain the generated displacement and internal force data, call the reinforced concrete reinforcement module to automatically analyze the data, and obtain the tunnel boring machine segment reinforcement data; Obtain model parameters, model displacement and internal force data, cloud map and reinforcement data, call the structural calculation report generation module, and obtain the structural calculation report.

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