A dynamic simulation method and system for synchronous grouting of shield tunnels under the action of flowing water

Abstract

The present invention provides a dynamic simulation method and system for synchronous grouting of shield tunnels under the action of flowing water, which relates to the technical field of tunnels and underground engineering, and includes: obtaining the geometric parameters of the tail gap of the shield, formation characteristic parameters, groundwater dynamics parameters, initial slurry physical property parameters and shield propulsion parameters in the area to be constructed; establishing a geometric model according to the geometric parameters of the tail gap of the shield and the shield propulsion parameters; setting dynamic boundary conditions and physical parameters according to the geometric model, formation characteristic parameters, groundwater dynamics parameters, initial slurry physical property parameters and shield propulsion parameters to obtain a computational domain and dynamic grid rules; performing simulation according to the computational domain and dynamic grid rules to obtain slurry distribution data; obtaining an evaluation result according to the slurry distribution data; performing parameter optimization according to the evaluation result to obtain optimized slurry physical property parameters. The present invention accurately quantifies the influence of flowing water on the slurry diffusion process by constructing a comparative simulation under flowing water and non-flowing water conditions.

Description

Technical Field

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

[0002] Synchronous grouting is one of the conventional processes for shield tunnels. By injecting grout into the gap formed by the shield tail void, the stability of the stratum and the segment is maintained. Generally, synchronous grouting is carried out simultaneously with the shield tail void, and the gap is filled with grout instantaneously when it is generated. Therefore, synchronous grouting is a dynamic process that continuously progresses along the longitudinal direction of the tunnel. The starting position of the shield tail void has the longest grouting time during the whole process, while the stopping position of the shield tail void has the shortest grouting time. The grouting time affects the penetration effect of the grout in the stratum, so the distribution law of the grout along the longitudinal direction of the tunnel should be non-uniform. In existing research, the grouting layer along the longitudinal direction of the tunnel is mostly regarded as a uniform layer with equal thickness.

[0003] In addition, there is flowing water in the water-rich stratum. The slag discharge at the excavation face of the shield tail will cause pressure loss, which may be lower than the pressure at the grouting position of the shield tail. The pressure difference between the excavation face and the shield tail will also cause or intensify the flowing water. Under the action of flowing water, the grout will be washed away by the water flow, resulting in a reduction in the grouting effect, and even insufficient grouting, which affects the engineering safety. Current technologies mostly analyze the diffusion of grout under the action of flowing water through empirical formulas or simplified models, but these methods mostly ignore the interaction process between the grout and groundwater, and it is difficult to accurately simulate the influence of flowing water on the grout during the dynamic process, and cannot provide effective theoretical and data support for optimizing grouting parameters.

[0004] Based on the above defects of the existing technology, there is an urgent need for a dynamic simulation method and system for synchronous grouting of shield tunnels under the action of flowing water. Summary of the Invention

[0005] The purpose of the present invention is to provide a dynamic simulation method and system for synchronous grouting of shield tunnels under the action of flowing water to improve the above problems. To achieve the above purpose, the technical solutions adopted by the present invention are as follows:

[0006] In the first aspect, the present application provides a dynamic simulation method for synchronous grouting of shield tunnels under the action of flowing water, including:

[0007] Obtain the geometric parameters of the shield tail gap, stratum characteristic parameters, groundwater dynamics parameters, initial grout physical property parameters, and shield tunneling parameters of the area to be constructed;

[0008] According to the geometric parameters of the shield tail gap and the shield tunneling parameters, combined with the design requirements of the grouting port, inlet boundary, outlet boundary, and moving boundary, establish a geometric model of the initial state of the shield tail void through mesh generation and boundary setting;

[0009] Set dynamic boundary conditions and physical parameters according to the geometric model, the formation characteristic parameters, the groundwater dynamics parameters, the initial slurry physical properties parameters, and the shield tunneling parameters, and complete the generation rules of dynamic grids to obtain the calculation domain and dynamic grid rules for the synchronous grouting process;

[0010] Conduct simulations according to the calculation domain and dynamic grid rules, and obtain the slurry distribution data in the shield tail clearance and formation area under static water conditions and dynamic water conditions by separately setting boundary conditions for static water conditions and dynamic water conditions;

[0011] Calculate the grouting efficiency under dynamic water conditions based on the slurry distribution data and conduct an evaluation to obtain an evaluation result;

[0012] If the evaluation result does not meet the preset engineering requirements, optimize the initial slurry physical properties parameters according to the evaluation result to obtain the final optimized slurry physical properties parameters.

[0013] In a second aspect, the present application also provides a dynamic simulation system for synchronous grouting of shield tunnels under the action of dynamic water, including:

[0014] An acquisition module, configured to acquire the geometric parameters of the shield tail clearance, the formation characteristic parameters, the groundwater dynamics parameters, the initial slurry physical properties parameters, and the shield tunneling parameters of the area to be constructed;

[0015] A construction module, configured to establish a geometric model of the initial state of shield tail void according to the geometric parameters of the shield tail clearance and the shield tunneling parameters, in combination with the design requirements of the grouting port, the inlet boundary, the outlet boundary, and the moving boundary, through mesh division and boundary setting;

[0016] An assignment module, configured to set dynamic boundary conditions and physical parameters according to the geometric model, the formation characteristic parameters, the groundwater dynamics parameters, the initial slurry physical properties parameters, and the shield tunneling parameters, and complete the generation rules of dynamic grids to obtain the calculation domain and dynamic grid rules for the synchronous grouting process;

[0017] A simulation module, configured to conduct simulations according to the calculation domain and dynamic grid rules, and obtain the slurry distribution data in the shield tail clearance and formation area under static water conditions and dynamic water conditions by separately setting boundary conditions for static water conditions and dynamic water conditions;

[0018] An evaluation module, configured to calculate the grouting efficiency under dynamic water conditions based on the slurry distribution data and conduct an evaluation to obtain an evaluation result;

[0019] An optimization module, if the evaluation result does not meet the preset engineering requirements, optimize the initial slurry physical properties parameters according to the evaluation result to obtain the final optimized slurry physical properties parameters.

[0020] The beneficial effects of the present invention are as follows:

[0021] By constructing a comparative simulation under dynamic water and non-dynamic water conditions, the present invention accurately quantifies the influence of dynamic water on the slurry diffusion process. Using the quantitative index of grouting efficiency, it scientifically evaluates the grouting effect under dynamic water conditions, providing a reliable theoretical basis for the engineering safety in complex water-rich strata. By adopting the dynamic mesh division technology, it can generate meshes in real time and continuously update the mesh structure within the calculation domain with the dynamic process of shield tunneling, effectively coping with complex working conditions such as the change of tail clearance and the dynamic deformation of the stratum, and realizing the high-precision simulation of the synchronous grouting process. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0023] Figure 1 It is a schematic flow chart of a method for dynamic simulation of synchronous grouting of shield tunnels under the action of dynamic water described in the embodiments of the present invention;

[0024] Figure 2 It is a schematic structural diagram of a system for dynamic simulation of synchronous grouting of shield tunnels under the action of dynamic water described in the embodiments of the present invention

[0025] Figure 3 It is a technical implementation flow chart of the dynamic simulation of synchronous grouting of shield tunnels described in the embodiments of the present invention;

[0026] Figure 4 It is a schematic diagram of the geometric model of the initial state of tail void of the shield;

[0027] Figure 5 It is a schematic diagram of the slurry diffusion effect under non-dynamic water conditions;

[0028] Figure 6 It is a schematic diagram of the slurry diffusion effect under dynamic water conditions.

[0029] Markings in the figure: 1, stratum; 2, grouting pipe; 3, tail clearance; 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 OF THE EMBODIMENTS

[0030] To make the objectives, 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 with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. The components of the embodiments of the present invention usually described and illustrated in the accompanying 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 accompanying drawings is not intended to limit the scope of the claimed present invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0031] It should be noted that similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. At the same time, in the description of the present invention, the terms "first", "second", etc. are only used for differential description and cannot be construed as indicating or implying relative importance.

[0032] Embodiment 1:

[0033] This embodiment provides a dynamic simulation method for synchronous grouting of shield tunnels under the action of moving water.

[0034] See Figure 1 , which shows that this method includes step S100 to step S600.

[0035] Step S100: Obtain the geometric parameters of the tail clearance 3, formation property parameters, groundwater dynamics parameters, initial slurry physical property parameters, and shield tunneling parameters of the area to be constructed;

[0036] It should be noted that the geometric parameters of the tail clearance 3 are used to describe the initial spatial form between the tail of the shield and the formation 1, providing a spatial framework for establishing a geometric model; the formation property 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 a porous medium model; the groundwater dynamics parameters (such as moving water velocity and water pressure) directly affect the distribution law and scouring effect of the slurry under the condition of moving water; the initial slurry physical property parameters (such as density and viscosity) are closely related to the fluidity and filling performance of the slurry and are the key factors for controlling the grouting effect; the shield tunneling parameters (such as tunneling speed) provide the dynamic characteristics of time and space for dynamic mesh generation and boundary condition setting.

[0037] In practical applications, obtaining these parameters requires a combination of various means such as on-site surveys, laboratory tests, and engineering experience. For example, formation characteristic parameters can be obtained through geotechnical tests, groundwater dynamics parameters can be measured by an underground water flow velocity and pressure monitoring system, and slurry physical property parameters need to be tested by equipment such as a hydrometer and a rotational viscometer. The accuracy and representativeness of these data directly determine the reliability and engineering applicability of subsequent simulation calculations.

[0038] Step S200: According to the geometric parameters of the tail clearance 3 and the shield tunneling parameters, combined with the design requirements of the grouting port 5, the inlet boundary 6, the outlet boundary 7, and the moving boundary 4, establish a geometric model of the initial state of tail void by means of mesh generation and boundary setting.

[0039] Specifically, the implementation process of the synchronous grouting dynamic simulation technology for shield tunnels is as Figure 3 shown.

[0040] Furthermore, step S200 includes steps S210 to S230.

[0041] Step S210: According to the geometric parameters of the tail clearance 3 and the shield tunneling parameters, establish a geometric framework model by combining the shield tunneling path and the shape of the tail void, and generate a basic geometric framework for describing the area of the tail clearance 3.

[0042] Step S220: Based on the design requirements of the preset grouting port 5, the inlet boundary 6, and the outlet boundary 7, classify the functional requirements of different boundaries, and define the interaction between each boundary and the external environment to obtain physical boundary conditions.

[0043] Step S230: Perform mesh generation processing according to the physical boundary conditions of the basic geometric framework to obtain a geometric model.

[0044] It should be noted that the geometric parameters of the tail clearance 3 determine the basic shape of the tail space, while the shield tunneling parameters are constrained by the dynamic changes in the tunneling speed and path, enabling the geometric framework to reflect the dynamic characteristics of the tail void 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, classify the functional requirements of these boundaries and clarify their interaction with the external environment. As Figure 4As shown, the grouting port 5 serves as a pressure boundary to ensure that the grout is injected into the gap at a preset pressure; the inlet boundary 6 simulates the groundwater flow velocity to load the dynamic water conditions; 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 such boundary conditions transforms the geometric framework into a model with real physical significance through the assignment of physical properties. Subsequently, according to the defined geometric framework and physical boundary conditions, a reasonable mesh generation strategy is adopted to discretize the computational domain and generate a geometric model that can support dynamic simulation.

[0045] Step S300: Set the dynamic boundary conditions and physical parameters according to the geometric model, formation characteristic parameters, groundwater dynamics parameters, initial grout physical properties parameters, and shield tunneling parameters, and complete the generation rules of the dynamic mesh to obtain the computational domain and dynamic mesh rules for the synchronous grouting process;

[0046] Furthermore, step S300 includes steps S310 to S330.

[0047] 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, obtain the first computational domain with the description of permeability characteristics;

[0048] Step S320: Perform boundary condition loading processing based on the groundwater dynamics parameters and the initial grout physical properties parameters. By respectively setting the pressure boundary condition for the grouting port 5, the velocity boundary condition for the inlet boundary 6, the pressure boundary condition for the outlet boundary 7, and combining the shield tunneling parameters to set the propulsion velocity for the moving boundary 4, obtain the second computational domain with physical boundary conditions;

[0049] Step S330: Perform dynamic mesh division processing according to the second computational domain. By gradually increasing the mesh layer by layer along the shield tunneling direction and refining the mesh for the grouting area and the flow area, obtain the final computational domain and dynamic mesh rules.

[0050] It can be understood that the grouting process under the action of dynamic water is a two-phase flow problem of the interaction between the grout and water. Preferably, the VOF method in CFD is selected for simulation.

[0051] Among them, the VOF equation is:

[0052] ;

[0053] Among them, is the volume of fluid function, is the ratio of the volume of the target fluid in the cell to the cell volume; is the time; is the fluid velocity.

[0054] The interface between phases can be determined through the fluid volume function, thereby determining the spatial distribution law of the slurry, specifically as follows:

[0055] ;

[0056] 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 through parameters such as porosity; a hydrometer is used to measure the slurry density, and a rotational viscometer is used to measure the slurry viscosity, which are used as input parameters of the slurry. A pressure boundary is adopted at the grouting port 5, and the grouting pressure to be studied is set. The slurry volume fraction is set, and only the slurry is allowed to flow in. A velocity boundary is adopted at the inlet boundary 6, and the dynamic water flow velocity to be studied is set. The slurry volume fraction is set to 0, and only water is allowed to flow in. When the groundwater does not have an 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 voiding speed in the project, the moving speed of the moving boundary 4 is determined.

[0057] Furthermore, dynamic meshing is used to realize the process of real-time generation of meshes as the moving boundary 4 moves. The dynamic meshing generation methods include smoothing, layering, and remeshing. The smoothing method is applicable to all mesh types, allowing the mesh to deform and be extruded, but the number of meshes and nodes does not change, and it is not applicable to large deformation cases. The layering method is applicable to quadrilateral and prismatic meshes, and new meshes are generated by adding dynamic layers. Since the generated meshes are regular, the calculation efficiency is relatively high. The remeshing method is applicable to triangular and tetrahedral meshes, and new meshes are generated by adding meshes, which is applicable to complex models, but the calculation efficiency is low. Since the model of the synchronous grouting simulation process is regular and undergoes large deformation, the layering method is selected as the dynamic meshing generation method.

[0058] When using the layering method to generate meshes, the generation criterion of new meshes needs to meet the following conditions:

[0059] ;

[0060] Among them, is the unit height of the adjacent layer of the moving boundary 4; is the ideal unit height; is the splitting factor, and the generation time and size of new meshes can be set through these parameters. As the moving boundary 4 moves, the height of the adjacent layer meshes gradually increases. When it is greater than , new meshes are generated. And so on, the process of gradually generating the shield tail gap during synchronous grouting is realized through the continuous generation of meshes.

[0061] Step S400: Perform simulations according to the computational domain and dynamic mesh rules. By separately setting the boundary conditions of the static water condition and the flowing water condition, obtain the slurry distribution data in the tail shield gap 3 and the formation 1 area under the static water condition and the flowing water condition.

[0062] Furthermore, step S400 includes steps S410 to S430.

[0063] Step S410: Perform model initialization processing according to the computational domain and dynamic mesh rules. By defining the initial distribution state of the fluid in the computational domain and combining the initial positions and boundary relationships of the slurry and groundwater in the computational domain, obtain the initial computational model.

[0064] Step S420: Perform boundary condition loading and computational processing based on the initial computational model. By separately setting the fluid boundaries under the static water condition and the flowing water condition, perform the fluid interaction calculation within the time step, and simulate the diffusion process of the slurry in the formation 1 to obtain the slurry spatial distribution state under the static water condition and the flowing water condition.

[0065] Step S430: Perform slurry distribution monitoring processing based on the slurry spatial distribution state. By determining the volume fraction of the multiphase flow in the grid, identify the spatial distribution characteristics of the slurry in each area, and obtain the slurry distribution data in the tail shield gap 3 and the formation 1 area under the static water condition and the flowing water condition.

[0066] Specifically, the slurry volume fraction 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 flow 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, making the calculation more focused on the slurry diffusion behavior in the formation 1 and the shield tail gap 3, and at the same time provides a clear starting point for subsequent simulation calculations. Based on the initial calculation model, the boundary conditions of no flowing water condition and flowing water condition are loaded, and the fluid interaction calculation within the time step is run. Under the no flowing water condition, the outlet boundary pressure is set to 0, and under the flowing water condition, it is set to the corresponding pressure boundary in combination with the pressure distribution of the groundwater; at the same time, by setting the number of time steps and the time step length, the diffusion process of the slurry in the formation 1 is dynamically simulated. Through these settings, the model can capture the fluid interaction behavior of the slurry under the combined action of the penetration of the slurry in the formation 1, the groundwater flow, and the boundary pressure, so as to obtain the spatial distribution state of the slurry under the no flowing water condition and the flowing water condition, providing accurate calculation results for subsequent monitoring and analysis. Finally, based on the method of the multiphase flow volume fraction, the slurry distribution monitoring process is carried out on the calculation results under the no flowing water condition and the flowing water condition. By determining the multiphase flow volume fraction within the grid (i.e., the ratio of the volume of the target fluid in the grid to the unit volume), the spatial distribution characteristics of the slurry in each region within the calculation domain are identified. This process can not only monitor the injection volume of the slurry in the shield tail gap 3 and the formation 1 in real time, but also analyze the diffusion characteristics and proportion of the slurry in different regions, and obtain the slurry distribution data in the shield tail gap 3 and the formation 1 regions under the no flowing water condition and the flowing water condition. The slurry diffusion effects under the no flowing water condition and the flowing water action are respectively as Figure 5 and Figure 6 shown. Under the no flowing water condition, the slurry is mainly affected by the formation penetration characteristics and the grouting pressure, showing a relatively regular and uniform diffusion state. In the simulation of the flowing water condition, by introducing the dynamic flow velocity as the boundary condition, the scouring effect of the water flow on the slurry appears, resulting in a significant interference in the diffusion direction of the slurry.

[0067] Step S500: Calculate the grouting efficiency under the flowing water condition according to the slurry distribution data and conduct an evaluation to obtain an evaluation result;

[0068] Furthermore, step S500 includes step S510 to step S530.

[0069] Step S510: Conduct a calculation process for the volume of the target fluid according to the slurry distribution data. By the multiphase flow volume fraction within each grid, accumulate the volume distribution of the slurry in all grids to obtain the slurry volume in the formation region under the no flowing water condition and the flowing water condition;

[0070] Step S520: According to the slurry volume in the formation area and the preset grouting efficiency formula, by calculating the ratio of the slurry volume under the dynamic water condition to the slurry volume under the static water condition, quantify the influence of the dynamic water condition on the slurry diffusion behavior to obtain the grouting efficiency.

[0071] Step S530: Analyze the grouting effect under the dynamic water condition based on the grouting efficiency. By describing the numerical range of the grouting efficiency and the influence of dynamic water on the slurry diffusion, judge the actual effect of the grouting process under the dynamic water condition to obtain the evaluation result based on the grouting efficiency.

[0072] It should be noted that to analyze the grouting effect under the dynamic water condition, the grouting efficiency is defined as:

[0073] ;

[0074] where is the grouting efficiency; is the slurry volume in formation 1 under the dynamic water condition; is the slurry volume in formation 1 under the static water condition. Through the quantitative analysis of the grouting efficiency, the weakening degree of the dynamic water on the grouting effect is clarified.

[0075] Step S600: If the evaluation result does not meet the preset engineering requirements, optimize the initial slurry physical property parameters according to the evaluation result to obtain the final optimized slurry physical property parameters.

[0076] Furthermore, step S600 includes steps S610 to S630.

[0077] Step S610: Compare the evaluation result with the preset engineering requirements to identify whether the engineering requirements are met under the current grouting conditions; if the grouting efficiency is lower than the engineering requirements, the parameters need to be optimized; if it is met, the optimization process ends.

[0078] Step S620: Adjust the initial slurry physical property parameters by optimizing the physical property parameters and process parameters of the slurry, adjust the influencing factors of the slurry diffusion behavior under the dynamic water condition, generate a new combination of physical property parameters and process parameters to obtain the optimized slurry physical property parameters.

[0079] Step S630: Conduct simulation analysis according to the optimized slurry physical property parameters, repeat the simulation of the grouting process under the static water condition and the dynamic water condition, obtain the new grouting efficiency, and form a cyclic optimization mechanism until the evaluation result meets the preset engineering requirements.

[0080] 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 ability of 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, enhancing the construction safety and engineering adaptability; third, through the combination of simulation and optimization, a scientific basis for adjusting grouting parameters is provided, avoiding the blindness of traditional empirical design, and providing strong technical support for the grouting technology of shield tunnel construction under complex geological conditions.

[0081] Embodiment 2:

[0082] As Figure 2 shown, this embodiment provides a dynamic simulation system for synchronous grouting of shield tunnels under the action of dynamic water. The system includes:

[0083] An acquisition module 901, configured to acquire the geometric parameters of the shield tail clearance, formation characteristic parameters, groundwater dynamics parameters, initial slurry physical property parameters, and shield propulsion parameters of the area to be constructed;

[0084] A construction module 902, configured to establish a geometric model of the initial state of shield tail void according to the geometric parameters of the shield tail clearance and the shield propulsion parameters, combined with the design requirements of the grouting port, inlet boundary, outlet boundary, and moving boundary, through mesh division and boundary setting;

[0085] An assignment module 903, configured to set dynamic boundary conditions and physical parameters according to the geometric model, formation characteristic parameters, groundwater dynamics parameters, initial slurry physical property parameters, and shield propulsion parameters, and complete the generation rules of dynamic meshes, to obtain the computational domain and dynamic mesh rules of the synchronous grouting process;

[0086] A simulation module 904, configured to perform simulation according to the computational domain and dynamic mesh rules, and obtain the slurry distribution data of the shield tail clearance and the formation area under the conditions of no dynamic water and dynamic water by respectively setting the boundary calculations of no dynamic water condition and dynamic water condition;

[0087] An evaluation module 905, configured to calculate the grouting efficiency under the dynamic water condition according to the slurry distribution data and perform an evaluation to obtain an evaluation result;

[0088] An optimization module 906, if the evaluation result does not meet the preset engineering requirements, then perform parameter optimization on the initial slurry physical property parameters according to the evaluation result to obtain the final optimized slurry physical property parameters.

[0089] In a specific implementation manner disclosed in the present invention, the construction module 902 includes:

[0090] The first construction unit is used to establish a geometric framework model by combining the shield tunneling path and the shape of the shield tail void according to the geometric parameters of the shield tail clearance and the shield tunneling parameters, and generate a basic geometric framework for describing the shield tail clearance area;

[0091] The second construction unit, based on the design requirements of the preset grouting ports, inlet boundaries, and outlet boundaries, classifies the functional requirements of different boundaries and defines the interaction between each boundary and the external environment to obtain physical boundary conditions;

[0092] The third construction unit is used to perform mesh division processing according to the physical boundary conditions of the basic geometric framework to obtain a geometric model.

[0093] In a specific embodiment disclosed by the present invention, the assignment module 903 includes:

[0094] The first assignment unit is used to obtain a first computational domain with a description of the seepage characteristics by loading the formation seepage characteristics and the porous medium model according to the framework area of the geometric model and the formation characteristic parameters;

[0095] The second assignment unit performs boundary condition loading processing based on the groundwater dynamics parameters and the initial slurry physical properties parameters. By respectively setting a pressure boundary condition for the grouting port, a velocity boundary condition for the inlet boundary, a pressure boundary condition for the outlet boundary, and setting a propulsion velocity for the moving boundary in combination with the shield tunneling parameters, a second computational domain with physical boundary conditions is obtained;

[0096] The third assignment unit is used to perform dynamic mesh division processing according to the second computational domain. By gradually increasing the mesh layer by layer along the shield tunneling direction and performing mesh refinement processing on the grouting area and the flow area, the final computational domain and the dynamic mesh rules are obtained.

[0097] In a specific embodiment disclosed by the present invention, the simulation module 904 includes:

[0098] The first simulation unit is used to perform model initialization processing according to the computational domain and the dynamic mesh rules. By defining the initial distribution state of the fluid in the computational domain and combining the initial positions and boundary relationships of the slurry and groundwater in the computational domain, an initial computational model is obtained;

[0099] The second simulation unit is used to perform boundary condition loading and calculation processing according to the initial computational model. By respectively setting the fluid boundaries under the conditions of no flowing water and flowing water, running the fluid interaction calculation within the time step length, and simulating the diffusion process of the slurry in the formation, the spatial distribution states of the slurry under the conditions of no flowing water and flowing water are obtained;

[0100] The third simulation unit is used to monitor and process the slurry distribution according to the slurry spatial distribution state. By determining the multiphase flow volume fraction in the grid, it identifies the spatial distribution characteristics of the slurry in each area, and obtains the slurry distribution data in the shield tail gap and the formation area under static water conditions and flowing water conditions.

[0101] In a specific embodiment disclosed by the present invention, the evaluation module 905 includes:

[0102] The first evaluation unit is used to calculate and process the volume of the target fluid according to the slurry distribution data. By the multiphase flow volume fraction in each grid, it accumulates the volume distribution of the slurry in all grids, and obtains the slurry volume in the formation area under static water conditions and flowing water conditions.

[0103] The second evaluation unit is used to quantify the influence of flowing water conditions on the slurry diffusion behavior according to the slurry volume in the formation area and the preset grouting efficiency formula. By calculating the ratio of the slurry volume under flowing water conditions to the slurry volume under static water conditions, it obtains the grouting efficiency.

[0104] The third evaluation unit is used to analyze the grouting effect under flowing water conditions according to the grouting efficiency. By describing the numerical range of the grouting efficiency and the influence of flowing water on the slurry diffusion, it judges the actual effect of the grouting process under flowing water conditions, and obtains the evaluation result based on the grouting efficiency.

[0105] In a specific embodiment disclosed by the present invention, the optimization module 906 includes:

[0106] The first optimization unit is used to compare the evaluation result with the preset engineering requirements to identify whether the current grouting conditions meet the engineering needs. If the grouting efficiency is lower than the engineering requirements, the parameters need to be optimized. If it meets the requirements, the optimization process ends.

[0107] The second optimization unit is used to adjust the initial slurry physical property parameters. By optimizing the physical property parameters and process parameters of the slurry, it adjusts the influencing factors of the slurry diffusion behavior under flowing water conditions, generates a new combination of physical property parameters and process parameters, and obtains the optimized slurry physical property parameters.

[0108] The third optimization unit is used to perform simulation analysis according to the optimized slurry physical property parameters. It repeats the simulation of the grouting process under static water conditions and flowing water conditions to obtain a new grouting efficiency, and forms a cyclic optimization mechanism until the evaluation result reaches the preset engineering requirements.

[0109] As mentioned above, the above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of changes or substitutions, which should be covered within 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 the final optimized slurry physical property parameters; Among them, according to the geometric model, the formation characteristic parameters, the groundwater dynamic parameters, the initial slurry physical parameters and the shield propulsion parameters, the dynamic boundary conditions and physical parameters are set, and the generation rules of the dynamic grid 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; Performing dynamic mesh division 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; Among them, simulation is performed according to the calculation domain and dynamic grid rules, 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 boundaries 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.

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: 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.

4. A dynamic simulation system for synchronous grouting of a shield tunnel under dynamic water, 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; An optimization module, if the evaluation result does not meet the preset engineering requirements, then optimize the initial slurry physical property parameters according to the evaluation result to obtain the final optimized slurry physical property parameters; Wherein, the assignment module 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 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 performing mesh refinement processing on the grouting area and the flow area, so as to obtain the final calculation domain and dynamic mesh rules; Wherein, the simulation module includes: 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.

5. A dynamic simulation system for synchronous grouting of a shield tunnel under dynamic water action according to claim 4, 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.

6. The dynamic simulation system for synchronous grouting of a shield tunnel under dynamic water action according to claim 4 is 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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