Shield tunnel synchronous grouting dynamic simulation method and system under action of dynamic water

Abstract

The invention provides a dynamic simulation method and system for synchronous grouting of a shield tunnel under the action of dynamic water, and relates to the technical field of tunnel and underground engineering, and the method comprises the following steps: obtaining a shield tail gap geometric parameter, a stratum characteristic parameter, an underground water dynamic parameter, an initial slurry physical property parameter and a shield propulsion parameter of a to-be-constructed area; establishing a geometric model according to the shield tail gap geometric parameters and the shield propulsion parameters; setting dynamic boundary conditions and physical parameters according to the geometric model, the stratum characteristic parameters, the underground water dynamic parameters, the initial slurry physical parameters and the shield propulsion parameters to obtain a computational domain and a dynamic grid rule; performing simulation according to the computational domain and the dynamic grid rule to obtain slurry distribution data; obtaining an evaluation result according to the slurry distribution data; and performing parameter optimization according to an evaluation result to obtain optimized slurry physical property parameters. According to the method, the influence of flowing water on the slurry diffusion process is accurately quantified by constructing comparative simulation under the flowing water condition and the non-flowing water condition.

Description

Technical Field

[0001] The invention relates to the technical field of tunnels and underground engineering, and in particular to a method and system for dynamic simulation of synchronous grouting of a shield tunnel under the action of dynamic water. Background Art

[0002] Synchronous grouting is one of the conventional processes in shield tunnels. The stability of the stratum and the segments is maintained by injecting slurry into the gap formed by the hollowing of the shield tail. Generally speaking, synchronous grouting and hollowing of the shield tail are carried out simultaneously, and the gap is filled with slurry the moment it is generated. Therefore, synchronous grouting is a dynamic process that continues along the longitudinal direction of the tunnel. The grouting time at the starting position of the hollowing of the shield tail is the longest in the whole process, while the grouting time at the stopping position of the hollowing of the shield tail is the shortest. The grouting time affects the penetration effect of the slurry in the stratum, so the distribution law of the slurry along the longitudinal direction of the tunnel should be uneven. In existing studies, the grouting layer along the longitudinal direction of the tunnel is mostly regarded as a uniform layer of equal thickness.

[0003] In addition, there is dynamic water in the water-rich strata, and the slag discharge from the shield tail excavation surface will cause pressure loss, which may be lower than the pressure at the shield tail grouting position. The pressure difference between the excavation surface and the shield tail will also cause dynamic water or aggravate dynamic water. Under the action of dynamic water, the slurry will be washed away by the water flow, resulting in a decrease in the grouting effect, or even insufficient grouting affecting the safety of the project. Current technologies mostly use empirical formulas or simplified models to analyze the diffusion of slurry under the action of dynamic water, but most of these methods ignore the interaction process between slurry and groundwater, and it is difficult to accurately simulate the influence of dynamic water on slurry in the dynamic process, and it is impossible to provide effective theoretical and data support for optimizing grouting parameters.

[0004] Based on the above-mentioned defects of the prior art, there is an urgent need for a dynamic simulation method and system for synchronous grouting of a shield tunnel under the action of dynamic water. Summary of the invention

[0005] The purpose of the present invention is to provide a method and system for dynamic simulation of synchronous grouting of a shield tunnel under dynamic water action to improve the above problems. In order to achieve the above purpose, the technical solution adopted by the present invention is as follows: In a first aspect, the present application provides a method for dynamic simulation of synchronous grouting of a shield tunnel under dynamic water action, comprising: Obtain the shield tail gap geometry parameters, formation characteristic parameters, groundwater dynamic parameters, initial slurry physical parameters and shield propulsion parameters in the area to be constructed; According to the geometric parameters of the shield tail gap and the shield propulsion parameters, combined with the design requirements of the grouting port, the inlet boundary, the outlet boundary and the moving boundary, a geometric model of the initial state of the shield tail being free is established through mesh division and boundary setting; According to the geometric model, the formation characteristic parameters, the groundwater dynamic parameters, the initial slurry physical property parameters and the shield propulsion parameters, dynamic boundary conditions and physical parameters are set, and dynamic grid generation rules are completed to obtain the calculation domain and dynamic grid rules of the synchronous grouting process; Simulation is performed according to the calculation domain and dynamic grid rules, and slurry distribution data of the shield tail gap and the formation area under the conditions of no moving water and moving water are obtained by setting the boundary calculations of the conditions of no moving water and moving water respectively; Calculating the grouting efficiency under dynamic water conditions according to the slurry distribution data and evaluating to obtain an evaluation result; If the evaluation result does not meet the preset engineering requirements, the initial slurry physical property parameters are optimized according to the evaluation result to obtain final optimized slurry physical property parameters.

[0006] In a second aspect, the present application also provides a dynamic simulation system for synchronous grouting of a shield tunnel under dynamic water action, comprising: The acquisition module is used to obtain the shield tail gap geometry parameters, formation characteristic parameters, groundwater dynamic parameters, initial slurry physical parameters and shield propulsion parameters of the area to be constructed; A construction module is used to establish a geometric model of the initial state of the shield tail being free of air through meshing and boundary setting according to the geometric parameters of the shield tail gap and the shield propulsion parameters, combined with the design requirements of the grouting port, the inlet boundary, the outlet boundary and the moving boundary; An assignment module is used to set dynamic boundary conditions and physical parameters according to the geometric model, the formation characteristic parameters, the groundwater dynamic parameters, the initial slurry physical property parameters and the shield propulsion parameters, and complete the generation rules of the dynamic grid to obtain the calculation domain and dynamic grid rules of the synchronous grouting process; A simulation module is used to perform simulation according to the calculation domain and dynamic grid rules, and obtain slurry distribution data of the shield tail gap and the formation area under the conditions of no moving water and moving water by setting the boundaries of the conditions of no moving water and moving water respectively; An evaluation module, used to calculate the grouting efficiency under dynamic water conditions according to the slurry distribution data and evaluate to obtain an evaluation result; The optimization module optimizes the initial slurry physical property parameters according to the evaluation results to obtain final optimized slurry physical property parameters if the evaluation results do not meet the preset engineering requirements.

[0007] The beneficial effects of the present invention are: The present invention accurately quantifies the influence of dynamic water on the slurry diffusion process by constructing comparative simulations under dynamic water and non-dynamic water conditions, and uses the grouting efficiency as a quantitative indicator to scientifically evaluate the grouting effect under dynamic water conditions, providing a reliable theoretical basis for engineering safety in complex water-rich strata. By adopting dynamic meshing technology, the present invention can generate meshes in real time, continuously update the mesh structure in the calculation domain with the dynamic process of shield advancement, effectively cope with complex working conditions such as shield tail gap changes and dynamic deformation of strata, and realize high-precision simulation of the synchronous grouting process. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0009] Figure 1 A schematic flow chart of a method for dynamic simulation of synchronous grouting in a shield tunnel under dynamic water action as described in an embodiment of the present invention; Figure 2 Schematic diagram of a dynamic simulation system for synchronous grouting of a shield tunnel under dynamic water action according to an embodiment of the present invention Figure 3 It is a flowchart of the implementation of the dynamic simulation technology of synchronous grouting in a shield tunnel described in an embodiment of the present invention; Figure 4 It is a schematic diagram of a geometric model of the initial state of the shield tail being free from air described in an embodiment of the present invention; Figure 5 It is a schematic diagram of the slurry diffusion effect under the condition of no moving water; Figure 6 Schematic diagram of slurry diffusion effect under dynamic water conditions.

[0010] Markings in the figure: 1. Strata; 2. Grouting pipe; 3. Shield tail gap; 4. Moving boundary; 5. Grouting port; 6. Inlet boundary; 7. Outlet boundary; 901. Acquisition module; 902. Construction module; 903. Assignment module; 904. Simulation module; 905. Evaluation module; 906. Optimization module. DETAILED DESCRIPTION

[0011] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0012] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. At the same time, in the description of the present invention, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0013] Embodiment 1: This embodiment provides a dynamic simulation method for synchronous grouting in a shield tunnel under the action of dynamic water.

[0014] See also Figure 1 , the figure shows that the method includes steps S100 to S600.

[0015] Step S100, obtaining the shield tail gap 3 geometric parameters, formation characteristic parameters, groundwater dynamic parameters, initial slurry physical property parameters and shield propulsion parameters of the area to be constructed; It should be noted that the geometric parameters of the shield tail gap 3 are used to describe the initial spatial morphology between the shield tail and the formation 1, providing a spatial framework for establishing the geometric model; the formation characteristic parameters (such as permeability and porosity) determine the penetration and diffusion behavior of the slurry in the formation 1, and are the core basis for establishing the porous media model; the groundwater dynamic parameters (such as dynamic water velocity and water pressure) directly affect the distribution law and scouring effect of the slurry under dynamic water conditions; the initial slurry physical properties (such as density and viscosity) are closely related to the fluidity and filling performance of the slurry, and are the key factors in controlling the grouting effect; the shield propulsion parameters (such as propulsion speed) provide dynamic characteristics of time and space for dynamic grid generation and boundary condition setting.

[0016] In practical applications, obtaining these parameters requires a combination of field surveys, laboratory tests, and engineering experience. For example, formation characteristic parameters can be obtained through geotechnical tests, groundwater dynamic parameters can be measured through groundwater velocity and pressure monitoring systems, and slurry physical parameters need to be tested by equipment such as hydrometers and rotational viscometers. The accuracy and representativeness of these data directly determine the reliability of subsequent simulation calculations and engineering applicability.

[0017] Step S200, according to the geometric parameters of the shield tail gap 3 and the shield propulsion parameters, combined with the design requirements of the grouting port 5, the inlet boundary 6, the outlet boundary 7 and the moving boundary 4, a geometric model of the shield tail empty initial state is established through mesh division and boundary setting; Specifically, the implementation process of the dynamic simulation technology of synchronous grouting in shield tunnels is as follows: Figure 3 shown.

[0018] Further, step S200 includes step S210 to step S230.

[0019] Step S210, according to the geometric parameters of the shield tail gap 3 and the shield propulsion parameters, a geometric framework model is established by combining the shield propulsion path and the shape of the shield tail clearance, and a basic geometric framework for describing the shield tail gap 3 area is generated; Step S220, based on the preset design requirements of the grouting port 5, the inlet boundary 6 and the outlet boundary 7, the functional requirements of different boundaries are classified, and the interaction between each boundary and the external environment is defined to obtain the physical boundary conditions; Step S230: Perform meshing processing according to the physical boundary conditions of the basic geometric framework to obtain a geometric model.

[0020] It should be noted that the geometric parameters of the shield tail gap 3 determine the basic form of the shield tail space, while the shield propulsion parameters constrain the dynamic changes of the propulsion speed and path, so that the geometric framework can reflect the dynamic characteristics of the shield tail de-airing area during the actual construction process. On this basis, according to the design requirements of the grouting port 5, the inlet boundary 6 and the outlet boundary 7, the functional requirements of these boundaries are classified, and their interaction with the external environment is clarified. Figure 4 As shown in the figure, the grouting port 5 is used as a pressure boundary to ensure that the slurry is injected into the gap at a preset pressure; the inlet boundary 6 simulates the groundwater flow rate to load the dynamic water condition; the outlet boundary is set to zero pressure or groundwater pressure according to the specific working conditions to ensure that the boundary conditions are consistent with the actual project. The loading of this boundary condition transforms the geometric framework into a model with real physical meaning through the assignment of physical properties. Subsequently, according to the defined geometric framework and physical boundary conditions, a reasonable meshing strategy is used to discretize the computational domain to generate a geometric model that can support dynamic simulation.

[0021] Step S300, setting dynamic boundary conditions and physical parameters according to the geometric model, formation characteristic parameters, groundwater dynamic parameters, initial slurry physical parameters and shield propulsion parameters, and completing the generation rules of the dynamic grid to obtain the calculation domain and dynamic grid rules of the synchronous grouting process; Further, step S300 includes step S310 to step S330.

[0022] Step S310: According to the framework area of ​​the geometric model and the formation characteristic parameters, by loading the formation permeability characteristics and the porous medium model, a first calculation domain having a description of the permeability characteristics is obtained; Step S320, performing boundary condition loading processing based on groundwater dynamic parameters and initial slurry physical property parameters, by respectively setting pressure boundary conditions for the grouting port 5, setting velocity boundary conditions for the inlet boundary 6, setting pressure boundary conditions for the outlet boundary 7, and setting a propulsion speed for the moving boundary 4 in combination with the shield propulsion parameters, to obtain a second calculation domain with physical boundary conditions; Step S330: Perform dynamic meshing processing according to the second computational domain, by adding meshes layer by layer along the shield advancement direction, and performing mesh refinement processing on the grouting area and the flow area, to obtain the final computational domain and dynamic mesh rules.

[0023] It is understandable that the grouting process under the action of dynamic water is a two-phase flow problem of interaction between slurry and water. Preferably, the VOF method in CFD is used for simulation.

[0024] The VOF equation is: ; in, is the fluid volume function, is the ratio of the target fluid volume in the unit to the unit volume; For time; is the fluid velocity.

[0025] The interface between phases can be determined by the fluid volume function, and thus the spatial distribution law of the slurry can be determined, specifically: ; Specifically, a porous medium model is used to simulate the formation 1, and the permeability characteristics of the target formation to be studied are reflected by parameters such as porosity; a hydrometer is used to test the slurry density, and a rotational viscometer is used to test the slurry viscosity, which are used as the input parameters of the slurry. A pressure boundary is used at the grouting port 5 to set the grouting pressure to be studied. The slurry volume fraction is set to only allow the slurry to flow in. A velocity boundary is used at the inlet boundary 6 to set the dynamic water flow rate to be studied. The slurry volume fraction is set to 0, and only water is allowed to flow in. When the groundwater does not have obvious water pressure, the outlet boundary is a pressure boundary with a pressure of 0; when the groundwater pressure is large, the outlet boundary is set to the water pressure to be studied. According to the shield tail de-airing speed in the project, the moving speed of the moving boundary 4 is determined.

[0026] Furthermore, a dynamic mesh is used to realize the process of real-time generation of the mesh as the moving boundary 4 moves. The dynamic mesh generation methods include smoothing, layering and reconstruction. The smoothing method is applicable to all mesh types and allows the mesh to be deformed and extruded, but the number of meshes and nodes does not change, and it is not applicable to large deformation situations. The layering method is applicable to quadrilateral and prismatic meshes. New meshes are generated by adding dynamic layers. Due to the regularity of the generated mesh, the calculation efficiency is high. The reconstruction method is applicable to triangular and tetrahedral meshes. New meshes are generated by adding meshes. It is applicable to complex model situations, but the calculation efficiency is low. Due to the model regularity of the synchronous grouting simulation process and the large deformation, the layering method is selected as the dynamic mesh generation method.

[0027] When using the layer-laying method to generate a grid, the following conditions must be met to determine the generation criteria for the new grid: ; in, is the unit height of the adjacent layer of moving boundary 4; is the ideal unit height; is the splitting factor. These parameters can be used to set the generation time and size of new grids. As the moving boundary 4 moves, the height of the adjacent grids increases. Gradually increasing, greater than A new grid is generated when the shield tail gap is gradually generated. Similarly, the process of gradually generating the synchronous grouting shield tail gap is realized by continuously generating grids.

[0028] Step S400, simulating according to the calculation domain and dynamic grid rules, and obtaining slurry distribution data of the shield tail gap 3 and the formation 1 area under the conditions of no moving water and moving water by setting the boundaries of the conditions of no moving water and moving water respectively; Further, step S400 includes step S410 to step S430.

[0029] Step S410, performing model initialization processing according to the calculation domain and dynamic grid rules, by defining the initial distribution state of the fluid in the calculation domain and combining the initial positions and boundary relationships of the slurry and groundwater in the calculation domain, an initial calculation model is obtained; Step S420, loading and calculating boundary conditions according to the initial calculation model, respectively setting the fluid boundaries under the condition of no moving water and the condition of moving water, running the fluid interaction calculation within the time step, simulating the diffusion process of the slurry in the formation 1, and obtaining the spatial distribution state of the slurry under the condition of no moving water and the condition of moving water; Step S430, perform slurry distribution monitoring and processing according to the spatial distribution state of the slurry, identify the spatial distribution characteristics of the slurry in each area by determining the multiphase flow volume fraction in the grid, and obtain the slurry distribution data in the shield tail gap 3 and the formation 1 area under the conditions of no moving water and moving water.

[0030] Specifically, the volume fraction of the slurry in the grouting pipe 2 is set to 1, and the pressure is the grouting pressure; while the initial volume fraction and pressure of the slurry in the formation 1 are both set to 0, and the dynamic water velocity of the groundwater is defined by the inlet boundary 6. This initialization process simplifies the complexity of the slurry flow in the grouting pipe 2, so that the calculation focuses more on the slurry diffusion behavior in the formation 1 and the shield tail gap 3, and provides a clear starting point for subsequent simulation calculations. On the basis of the initial calculation model, the boundary conditions of the non-dynamic water condition and the dynamic water condition are loaded, and the fluid interaction calculation within the time step is run. Under the non-dynamic water condition, the outlet boundary pressure is set to 0, while under the dynamic water condition, it is set to the corresponding pressure boundary in combination with the pressure distribution of the groundwater; at the same time, the diffusion process of the slurry in the formation 1 is dynamically simulated by setting the number of time steps and the time step. Through these settings, the model can capture the fluid interaction behavior of the slurry under the combined action of the penetration of the formation 1, the groundwater flow and the boundary pressure, so as to obtain the spatial distribution state of the slurry under the non-dynamic water condition and the dynamic water condition, providing accurate calculation results for subsequent monitoring and analysis. Finally, based on the multiphase flow volume fraction method, the calculation results under the conditions of no moving water and moving water are monitored for slurry distribution. By determining the multiphase flow volume fraction in the grid (i.e., the ratio of the target fluid volume to the unit volume in the grid), the spatial distribution characteristics of the slurry in each area in the calculation domain are identified. This process can not only monitor the injection volume of slurry in the shield tail gap 3 and the formation 1 in real time, but also analyze the diffusion characteristics and proportion of slurry in different areas, and obtain the slurry distribution data in the shield tail gap 3 and the formation 1 area under the conditions of no moving water and moving water. The slurry diffusion effects under the conditions of no moving water and under the action of moving water are shown as follows: Figure 5 and Figure 6As shown. Under the condition of no moving water, the slurry is mainly affected by the permeability characteristics of the formation and the grouting pressure, showing a relatively regular and uniform diffusion state. In the simulation of moving water conditions, by introducing the moving water velocity as a boundary condition, the scouring effect of the water flow on the slurry is apparent, resulting in a significant disturbance in the diffusion direction of the slurry.

[0031] Step S500, calculating the grouting efficiency under dynamic water conditions according to the slurry distribution data and evaluating to obtain an evaluation result; Further, step S500 includes step S510 to step S530.

[0032] Step S510: Calculate the target fluid volume according to the slurry distribution data, accumulate the volume distribution of the slurry in all grids through the multiphase flow volume fraction in each grid, and obtain the slurry volume in the formation area under the condition of no moving water and the condition of moving water; Step S520, according to the slurry volume in the formation area and the preset grouting effectiveness formula, by calculating the ratio of the slurry volume under the dynamic water condition to the slurry volume under the non-dynamic water condition, the influence of the dynamic water condition on the slurry diffusion behavior is quantified to obtain the grouting effectiveness; Step S530, analyzing the grouting effect under dynamic water conditions according to the grouting efficiency, judging the actual effect of the grouting process under dynamic water conditions by describing the numerical range of the grouting efficiency and the influence of dynamic water on the diffusion of the slurry, and obtaining an evaluation result based on the grouting efficiency.

[0033] It should be noted that in order to analyze the grouting effect under dynamic water conditions, the grouting efficiency is defined as: ; in, To ensure efficient grouting; is the volume of slurry in formation 1 under dynamic water conditions; is the volume of slurry in the water-free formation 1. Through the quantitative analysis of grouting efficiency, the degree of weakening of grouting effect by dynamic water is clarified.

[0034] Step S600: If the evaluation result does not meet the preset engineering requirements, the initial slurry physical property parameters are optimized according to the evaluation result to obtain the final optimized slurry physical property parameters.

[0035] Further, step S600 includes step S610 to step S630.

[0036] Step S610: Compare the evaluation results with the preset engineering requirements to identify whether the current grouting conditions meet the engineering requirements; if the grouting efficiency is lower than the engineering requirements, the parameters need to be optimized; if they are satisfied, the optimization process ends; Step S620, adjusting the initial slurry physical property parameters by optimizing the slurry physical property parameters and process parameters, adjusting the influencing factors on the slurry diffusion behavior under dynamic water conditions, generating a new combination of physical property parameters and process parameters, and obtaining optimized slurry physical property parameters; Step S630, perform simulation analysis based on the optimized slurry physical property parameters, repeatedly run the grouting process simulation under non-moving water conditions and moving water conditions, obtain a new grouting efficiency, and form a cyclic optimization mechanism until the evaluation results meet the preset engineering requirements.

[0037] It can be understood that the technical effects of the above steps are reflected in the following aspects: First, through the closed-loop optimization mechanism, the dynamic adjustment capability of the grouting design is ensured, making the design process more flexible and efficient; second, through parameter optimization, the diffusion effect of the slurry and the grouting efficiency under dynamic water conditions are significantly improved, thereby enhancing construction safety and engineering adaptability; third, through the combination of simulation and optimization, a scientific basis for grouting parameter adjustment is provided, avoiding the blindness of traditional empirical design, and providing strong technical support for grouting technology in shield tunnel construction under complex geological conditions.

[0038] Embodiment 2: like Figure 2 As shown, this embodiment provides a dynamic simulation system for synchronous grouting of a shield tunnel under dynamic water action, and the system includes: Acquisition module 901, used to acquire shield tail gap geometric parameters, formation characteristic parameters, groundwater dynamic parameters, initial slurry physical parameters and shield propulsion parameters in the area to be constructed; The construction module 902 is used to establish a geometric model of the initial state of the shield tail being free of air through meshing and boundary setting according to the geometric parameters of the shield tail gap and the shield propulsion parameters, combined with the design requirements of the grouting port, the inlet boundary, the outlet boundary and the moving boundary; The assignment module 903 is used to set dynamic boundary conditions and physical parameters according to the geometric model, formation characteristic parameters, groundwater dynamic parameters, initial slurry physical parameters and shield propulsion parameters, and complete the generation rules of the dynamic grid to obtain the calculation domain and dynamic grid rules of the synchronous grouting process; The simulation module 904 is used to perform simulation according to the calculation domain and the dynamic grid rule, and obtain the slurry distribution data of the shield tail gap and the formation area under the conditions of no moving water and moving water by setting the boundary calculation of the conditions of no moving water and moving water respectively; Evaluation module 905, used to calculate the grouting efficiency under dynamic water conditions according to the slurry distribution data and evaluate to obtain an evaluation result; Optimization module 906, if the evaluation result does not meet the preset engineering requirements, the initial slurry physical property parameters are optimized according to the evaluation result to obtain the final optimized slurry physical property parameters.

[0039] In a specific embodiment of the present invention, the construction module 902 includes: The first construction unit is used to establish a geometric framework model according to the shield tail gap geometric parameters and shield propulsion parameters by combining the shield propulsion path and the shape of the shield tail clearance, so as to generate a basic geometric framework for describing the shield tail gap area; The second construction unit, based on the design requirements of the preset grouting port, inlet boundary and outlet boundary, classifies the functional requirements of different boundaries and defines the interaction between each boundary and the external environment to obtain the physical boundary conditions; The third construction unit is used to perform meshing processing according to the physical boundary conditions of the basic geometric framework to obtain a geometric model.

[0040] In a specific implementation of the present invention, the assignment module 903 includes: A first value assignment unit is used to obtain a first calculation domain with a permeability characteristic description by loading the formation permeability characteristic and the porous medium model according to the framework area of ​​the geometric model and the formation characteristic parameters; The second assignment unit performs boundary condition loading processing based on groundwater dynamic parameters and initial slurry physical property parameters, and sets pressure boundary conditions for the grouting port, velocity boundary conditions for the inlet boundary, and pressure boundary conditions for the outlet boundary, and sets the propulsion speed for the moving boundary in combination with the shield propulsion parameters, thereby obtaining a second calculation domain with physical boundary conditions; The third assignment unit is used to perform dynamic mesh division processing according to the second calculation domain, by adding meshes layer by layer along the shield advancement direction, and refining the meshes in the grouting area and the flow area, so as to obtain the final calculation domain and dynamic mesh rules.

[0041] In a specific embodiment disclosed in the present invention, the simulation module 904 includes: The first simulation unit is used to perform model initialization processing according to the calculation domain and dynamic grid rules, and obtain the initial calculation model by defining the initial distribution state of the fluid in the calculation domain and combining the initial position and boundary relationship of the slurry and groundwater in the calculation domain; The second simulation unit is used to load and calculate the boundary conditions according to the initial calculation model, and to simulate the diffusion process of the slurry in the formation by setting the fluid boundaries under the conditions of no moving water and moving water respectively, and running the fluid interaction calculation within the time step, so as to obtain the spatial distribution state of the slurry under the conditions of no moving water and moving water; The third simulation unit is used to monitor and process the slurry distribution according to the spatial distribution state of the slurry. By determining the volume fraction of the multiphase flow in the grid, the spatial distribution characteristics of the slurry in each area are identified, and the slurry distribution data in the shield tail gap and the formation area under the conditions of no moving water and moving water are obtained.

[0042] In a specific embodiment of the present invention, the evaluation module 905 includes: The first evaluation unit is used to calculate the target fluid volume according to the slurry distribution data, and to accumulate the volume distribution of the slurry in all grids through the multiphase flow volume fraction in each grid to obtain the slurry volume in the formation area under the non-flowing water condition and the flowing water condition; The second evaluation unit is used to quantify the influence of the dynamic water condition on the diffusion behavior of the slurry by calculating the ratio of the slurry volume under the dynamic water condition to the slurry volume under the non-dynamic water condition according to the slurry volume in the formation area and the preset grouting effectiveness formula, so as to obtain the grouting effectiveness; The third evaluation unit is used to analyze the grouting effect under dynamic water conditions according to the grouting efficiency. By describing the numerical range of the grouting efficiency and the influence of dynamic water on the diffusion of the slurry, the actual effect of the grouting process under dynamic water conditions is judged to obtain the evaluation result based on the grouting efficiency.

[0043] In a specific embodiment of the present invention, the optimization module 906 includes: The first optimization unit is used to compare the evaluation results with the preset engineering requirements to identify whether the current grouting conditions meet the engineering requirements; if the grouting efficiency is lower than the engineering requirements, the parameters need to be optimized; if they are satisfied, the optimization process ends; The second optimization unit is used to adjust the initial slurry physical property parameters by optimizing the slurry physical property parameters and process parameters, adjusting the influencing factors on the slurry diffusion behavior under dynamic water conditions, generating new physical property parameter and process parameter combinations, and obtaining optimized slurry physical property parameters; The third optimization unit is used to perform simulation analysis based on the optimized slurry physical property parameters, repeatedly run the grouting process simulation under non-moving water conditions and moving water conditions, obtain a new grouting efficiency, and form a cyclic optimization mechanism until the evaluation results meet the preset engineering requirements.

[0044] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A dynamic simulation method for synchronous grouting of a shield tunnel under dynamic water action, characterized in that: include: Obtain the shield tail gap geometry parameters, formation characteristic parameters, groundwater dynamic parameters, initial slurry physical parameters and shield propulsion parameters in the area to be constructed; According to the geometric parameters of the shield tail gap and the shield propulsion parameters, combined with the design requirements of the grouting port, the inlet boundary, the outlet boundary and the moving boundary, a geometric model of the initial state of the shield tail being free is established through mesh division and boundary setting; According to the geometric model, the formation characteristic parameters, the groundwater dynamic parameters, the initial slurry physical property parameters and the shield propulsion parameters, dynamic boundary conditions and physical parameters are set, and dynamic grid generation rules are completed to obtain the calculation domain and dynamic grid rules of the synchronous grouting process; Simulation is performed according to the calculation domain and dynamic grid rules, and slurry distribution data of the shield tail gap and the formation area under the conditions of no moving water and moving water are obtained by setting the boundary calculations of the conditions of no moving water and moving water respectively; Calculating the grouting efficiency under dynamic water conditions according to the slurry distribution data and evaluating to obtain an evaluation result; If the evaluation result does not meet the preset engineering requirements, the initial slurry physical property parameters are optimized according to the evaluation result to obtain final optimized slurry physical property parameters.

2. The method for dynamic simulation of synchronous grouting of a shield tunnel under dynamic water action according to claim 1 is characterized in that: According to the geometric parameters of the shield tail gap and the shield propulsion parameters, combined with the design requirements of the grouting port, the inlet boundary, the outlet boundary and the moving boundary, a geometric model of the initial state of the shield tail being free is established through mesh division and boundary setting, including: According to the shield tail gap geometric parameters and the shield propulsion parameters, a geometric framework model is established by combining the shield propulsion path and the shape of the shield tail clearance to generate a basic geometric framework for describing the shield tail gap area; Based on the design requirements of the preset grouting ports, inlet boundaries and outlet boundaries, the physical boundary conditions are obtained by classifying the functional requirements of different boundaries and defining the interaction between each boundary and the external environment; A meshing process is performed according to the physical boundary conditions of the basic geometric framework to obtain a geometric model.

3. The method for dynamic simulation of synchronous grouting of a shield tunnel under dynamic water action according to claim 1 is characterized in that: According to the geometric model, the formation characteristic parameters, the groundwater dynamic parameters, the initial slurry physical property parameters and the shield propulsion parameters, dynamic boundary conditions and physical parameters are set, and dynamic grid generation rules are completed to obtain the calculation domain and dynamic grid rules of the synchronous grouting process, including: According to the framework area of ​​the geometric model and the formation characteristic parameters, a first calculation domain having a description of the permeability characteristics is obtained by loading the formation permeability characteristics and the porous medium model; Based on the groundwater dynamic parameters and the initial slurry physical property parameters, boundary condition loading processing is performed, by respectively setting pressure boundary conditions for the grouting port, setting velocity boundary conditions for the inlet boundary, setting pressure boundary conditions for the outlet boundary, and setting the propulsion speed for the moving boundary in combination with the shield propulsion parameters, so as to obtain a second calculation domain with physical boundary conditions; Dynamic meshing is performed according to the second computational domain, by adding meshes layer by layer along the shield advancement direction, and by refining the meshes in the grouting area and the flow area, so as to obtain the final computational domain and dynamic mesh rules.

4. The method for dynamic simulation of synchronous grouting of a shield tunnel under dynamic water action according to claim 1 is characterized in that: According to the calculation domain and dynamic grid rules, simulation is performed, and the slurry distribution data of the shield tail gap and the formation area under the conditions of no moving water and moving water are obtained by setting the boundary calculation of the conditions of no moving water and moving water respectively, including: Performing model initialization processing according to the computational domain and dynamic grid rules, and obtaining an initial computational model by defining an initial distribution state of the fluid in the computational domain and combining initial positions and boundary relationships of the slurry and groundwater in the computational domain; According to the initial calculation model, boundary condition loading and calculation processing are performed, and fluid boundaries under non-moving water conditions and moving water conditions are set respectively, and fluid interaction calculation within the running time step is performed to simulate the diffusion process of slurry in the formation, so as to obtain the spatial distribution state of slurry under non-moving water conditions and moving water conditions; The slurry distribution monitoring and processing is performed according to the slurry spatial distribution state, and the spatial distribution characteristics of the slurry in each area are identified by determining the multiphase flow volume fraction in the grid, so as to obtain the slurry distribution data in the shield tail gap and the formation area under the conditions of no moving water and moving water.

5. The method for dynamic simulation of synchronous grouting of a shield tunnel under dynamic water action according to claim 1 is characterized in that: The grouting efficiency under dynamic water conditions is calculated based on the slurry distribution data and evaluated to obtain evaluation results, including: The target fluid volume is calculated based on the slurry distribution data. The volume fraction of the multiphase flow in each grid is used to accumulate the volume distribution of the slurry in all grids to obtain the slurry volume in the formation area under the conditions of no moving water and moving water. According to the slurry volume in the formation area and a preset grouting effectiveness formula, the slurry volume under the water-moving condition is calculated by ratio with the slurry volume under the water-free condition, so as to quantify the influence of the water-moving condition on the slurry diffusion behavior and obtain the grouting effectiveness; The grouting effect under dynamic water conditions is analyzed according to the grouting efficiency. By describing the numerical range of the grouting efficiency and the influence of dynamic water on the diffusion of slurry, the actual effect of the grouting process under dynamic water conditions is judged to obtain an evaluation result based on the grouting efficiency.

6. A dynamic simulation system for synchronous grouting of a shield tunnel under dynamic water action, characterized in that: include: The acquisition module is used to obtain the shield tail gap geometry parameters, formation characteristic parameters, groundwater dynamic parameters, initial slurry physical parameters and shield propulsion parameters of the area to be constructed; A construction module is used to establish a geometric model of the initial state of the shield tail being free of air through meshing and boundary setting according to the geometric parameters of the shield tail gap and the shield propulsion parameters, combined with the design requirements of the grouting port, the inlet boundary, the outlet boundary and the moving boundary; An assignment module is used to set dynamic boundary conditions and physical parameters according to the geometric model, the formation characteristic parameters, the groundwater dynamic parameters, the initial slurry physical property parameters and the shield propulsion parameters, and complete the generation rules of the dynamic grid to obtain the calculation domain and dynamic grid rules of the synchronous grouting process; A simulation module is used to perform simulation according to the calculation domain and dynamic grid rules, and obtain slurry distribution data of the shield tail gap and the formation area under the conditions of no moving water and moving water by setting the boundaries of the conditions of no moving water and moving water respectively; An evaluation module, used to calculate the grouting efficiency under dynamic water conditions according to the slurry distribution data and evaluate to obtain an evaluation result; The optimization module optimizes the initial slurry physical property parameters according to the evaluation results to obtain final optimized slurry physical property parameters if the evaluation results do not meet the preset engineering requirements.

7. A dynamic simulation system for synchronous grouting of a shield tunnel under dynamic water action according to claim 6, characterized in that: The building blocks include: The first construction unit is used to establish a geometric framework model according to the shield tail gap geometric parameters and the shield propulsion parameters by combining the shield propulsion path and the shape of the shield tail clearance, so as to generate a basic geometric framework for describing the shield tail gap area; The second construction unit, based on the design requirements of the preset grouting port, inlet boundary and outlet boundary, classifies the functional requirements of different boundaries and defines the interaction between each boundary and the external environment to obtain the physical boundary conditions; The third construction unit is used to perform meshing processing according to the physical boundary conditions of the basic geometric framework to obtain a geometric model.

8. The dynamic simulation system for synchronous grouting of a shield tunnel under dynamic water action according to claim 6 is characterized in that: The assignment module comprises: A first value assignment unit is used to obtain a first calculation domain with a permeability characteristic description by loading the formation permeability characteristic and the porous medium model according to the framework area of ​​the geometric model and the formation characteristic parameters; The second assignment unit performs boundary condition loading processing based on the groundwater dynamic parameters and the initial slurry physical property parameters, and obtains a second calculation domain with physical boundary conditions by respectively setting pressure boundary conditions for the grouting port, setting velocity boundary conditions for the inlet boundary, and setting pressure boundary conditions for the outlet boundary, and setting the advancement speed for the moving boundary in combination with the shield advancement parameters; The third assignment unit is used to perform dynamic mesh division processing according to the second calculation domain, by adding meshes layer by layer along the shield advancement direction, and refining the meshes in the grouting area and the flow area, to obtain the final calculation domain and dynamic mesh rules.

9. The dynamic simulation system for synchronous grouting of a shield tunnel under dynamic water action according to claim 6 is characterized in that: The simulation module comprises: A first simulation unit is used to perform model initialization processing according to the calculation domain and the dynamic grid rule, and obtain an initial calculation model by defining the initial distribution state of the fluid in the calculation domain and combining the initial positions and boundary relationships of the slurry and groundwater in the calculation domain; The second simulation unit is used to load and calculate the boundary conditions according to the initial calculation model, and to simulate the diffusion process of the slurry in the formation by setting the fluid boundaries under the condition of no moving water and the condition of moving water respectively, and to obtain the spatial distribution state of the slurry under the condition of no moving water and the condition of moving water; The third simulation unit is used to monitor and process the slurry distribution according to the spatial distribution state of the slurry, identify the spatial distribution characteristics of the slurry in each area by determining the multiphase flow volume fraction in the grid, and obtain the slurry distribution data in the shield tail gap and the formation area under the conditions of no moving water and moving water.

10. The dynamic simulation system for synchronous grouting of a shield tunnel under dynamic water action according to claim 6, characterized in that: The evaluation module includes: The first evaluation unit is used to calculate the target fluid volume according to the slurry distribution data, and to accumulate the volume distribution of the slurry in all grids through the multiphase flow volume fraction in each grid to obtain the slurry volume in the formation area under the non-flowing water condition and the flowing water condition; The second evaluation unit is used to quantify the influence of the dynamic water condition on the diffusion behavior of the slurry by calculating the ratio of the slurry volume under the dynamic water condition to the slurry volume under the non-dynamic water condition according to the slurry volume in the formation area and a preset grouting effectiveness formula, so as to obtain the grouting effectiveness; The third evaluation unit is used to analyze the grouting effect under dynamic water conditions according to the grouting efficiency. By describing the numerical range of the grouting efficiency and the influence of dynamic water on the diffusion of slurry, the actual effect of the grouting process under dynamic water conditions is judged to obtain an evaluation result based on the grouting efficiency.

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