Ship lock foundation pit anti-inrush calculation method and device based on finite element analysis

Abstract

This invention discloses a method and apparatus for calculating the anti-surge resistance of lock foundation pits based on finite element analysis, relating to the field of lock foundation pit technology or other related technical fields. The method includes: calling a three-dimensional fluid-structure interaction finite element model of the lock foundation pit to obtain elevation information of multiple excavation steps during the excavation process; inputting the elevation information into the three-dimensional fluid-structure interaction finite element model, calculating stress parameters for different soil layer types at each excavation step using the model; analyzing the stress parameters for different soil layer types at each excavation step using a predetermined shear stress detection criterion, determining the soil stability of the lock foundation pit, and outputting the anti-surge resistance judgment result of the lock foundation pit. This invention solves the technical problem in related technologies where the change in soil stress cannot be analyzed when verifying the anti-surge resistance stability of lock foundation pits against confined water, resulting in potential safety hazards in the project.

Description

Technical Field

[0001] This invention relates to the field of lock foundation pit technology or other related fields. Specifically, it relates to a method and apparatus for calculating the anti-surge of lock foundation pits based on finite element analysis. Background Technology

[0002] In lock foundation pit engineering, the sudden surge of confined water is a major safety hazard that can lead to pit instability, surface subsidence, cracking of surrounding structures, and even collapse. Due to the high groundwater level, thick aquifer, and large excavation depth (often exceeding 20m), the imbalance between the pressure of the confined water and the weight of the overlying impermeable layer can easily trigger a sudden surge disaster. On the other hand, the excavation depth of the foundation pit is often quite large (lock foundation pits are often more than 20m deep), which significantly weakens the thickness of the impermeable layer and significantly increases the risk of confined water damage.

[0003] In related technologies, the stability of the foundation pit against sudden inrush of confined water is generally verified by the pressure balance method (or "soil weight-water pressure balance method") according to the provisions of Article C.0.1 of the Technical Specification for Foundation Pit Support (JGJ 120-2012). The basic principle of this method is to compare the self-weight of the soil (including the buoyancy of groundwater) above the top surface of the confined water layer below the bottom of the pit with the supporting force of the confined water on the bottom of the pit.

[0004] However, the above-mentioned schemes have significant technical flaws: they only consider the gravity of the soil, neglecting the actual mechanical responses such as elastic deformation and stress redistribution. In reality, during the unloading process of the foundation pit excavation, the impermeable soil (such as clay layer) will undergo rebound deformation due to unloading, forming tensile stress zones internally, and the shear stress state will undergo nonlinear evolution. These factors directly affect its ability to resist damage from confined water. Furthermore, the above-mentioned schemes often deem "unsafe" even when the thickness of the impermeable layer is slightly insufficient, forcibly requiring additional engineering safety measures, leading to a significant increase in project costs.

[0005] There is currently no effective solution to the above problems. Summary of the Invention

[0006] This invention provides a method and apparatus for calculating the anti-surge resistance of lock foundation pits based on finite element analysis, which at least solves the technical problem in related technologies where the change of soil stress cannot be analyzed when verifying the anti-surge resistance stability of confined water in lock foundation pits, resulting in potential safety hazards in the project.

[0007] According to one aspect of the present invention, a method for calculating the anti-surge resistance of a lock foundation pit based on finite element analysis is provided, comprising: calling a three-dimensional fluid-structure interaction finite element model of the lock foundation pit, wherein the three-dimensional fluid-structure interaction finite element model is used to simulate the interaction between groundwater seepage pressure and soil deformation of the target lock; acquiring elevation information of multiple excavation steps during the excavation process of the lock foundation pit; inputting the elevation information into the three-dimensional fluid-structure interaction finite element model, calculating stress parameters of different soil layer types in each excavation step through the three-dimensional fluid-structure interaction finite element model; analyzing the stress parameters of different soil layer types in each excavation step using a predetermined shear stress detection criterion, determining the soil stability of the lock foundation pit, and outputting the anti-surge resistance judgment result of the lock foundation pit.

[0008] Optionally, before calling the three-dimensional fluid-structure interaction finite element model of the lock pit, the method further includes: acquiring regional data of the lock pit before excavation; modeling the excavation area based on the regional data and fluid-structure interaction analysis principles, and outputting basic model parameters, wherein the basic model parameters include: top elevation, bottom elevation, stratum elevation, and model foundation coordinate axes, the stratum elevation being the boundary between the confined aquifer and the impermeable layer; determining the model bottom based on the bottom elevation and the stratum elevation, and setting the model bottom as the fixed constraint boundary of the model; determining the model's horizontal symmetric constraint boundary based on the bottom elevation, the top elevation, and the surrounding interception positions; determining the top elevation of the confined aquifer and the confined aquifer pressure head height based on the pre-acquired confined aquifer location information and geological survey report, to determine the seepage boundary around the model; and generating the three-dimensional fluid-structure interaction finite element model of the lock pit based on the model's fixed constraint boundary, the model's horizontal symmetric constraint boundary, and the model's surrounding seepage boundary.

[0009] Optionally, after generating the three-dimensional fluid-structure interaction finite element model of the lock foundation pit, the method further includes: determining the various soil layer types to be filled in the lock foundation pit based on the geological survey report obtained after surveying the lock foundation pit; obtaining the elastic modulus, soil density, Poisson's ratio, cohesion, internal friction angle and permeability coefficient corresponding to each soil layer type, and obtaining the relevant calculation parameters of the soil layer.

[0010] Optionally, the step of obtaining elevation information of multiple excavation steps in the process of excavating the lock foundation pit includes: dividing the foundation pit excavation process into multiple excavation steps based on soil-related calculation parameters of various soil types in the lock foundation pit; determining the corresponding foundation pit excavation elevation information and foundation pit bottom elevation information for each excavation step, thereby obtaining the elevation information of the multiple excavation steps.

[0011] Optionally, the step of inputting the elevation information into the three-dimensional fluid-structure interaction finite element model and calculating the stress parameters of different soil layer types for each excavation step using the three-dimensional fluid-structure interaction finite element model includes: dividing the three-dimensional fluid-structure interaction finite element model into a mesh according to a preset soil mesh division precision, and outputting a model mesh element set; inputting the elevation information corresponding to each excavation step and the soil layer-related calculation parameters corresponding to each soil layer type into the three-dimensional fluid-structure interaction finite element model, and using the model mesh element set to perform simulation evolution operations of the displacement field and stress field for each excavation step; during the simulation evolution process, calculating the vertical displacement, pressure head, vertical stress, and shear stress values ​​for each soil layer type to obtain the stress parameters of different soil layer types for each excavation step.

[0012] Optionally, during the simulation evolution process, the steps of calculating the vertical displacement, pressure head, vertical stress, and shear stress values ​​of each soil layer type to obtain the stress parameters of different soil layer types in each excavation step include: in each excavation step, extracting the maximum shear stress component of all soil layer types at the Gaussian point of the soil; generating a three-dimensional shear stress field distribution map based on the maximum shear stress component through spatial interpolation; determining the shear stress value of each soil layer type based on the three-dimensional shear stress field distribution map; and storing the three-dimensional shear stress field distribution map in the storage module of the three-dimensional fluid-structure interaction finite element model in the form of isosurfaces and slices.

[0013] Optionally, the step of analyzing the stress parameters of different soil layer types in each excavation step using a predetermined shear stress detection criterion, determining the soil stability of the lock pit, and outputting the lock pit's anti-surge judgment result includes: performing sensitivity analysis on the non-uniformity of stratum distribution, the non-uniformity of soil shear strength index, and the change of confined hydraulic head based on the stress parameters of different soil layer types in each excavation step; selecting the modified Mohr-Coulomb criterion as the predetermined shear stress detection criterion based on the sensitivity analysis results and the structural characteristics of each soil layer type; obtaining the structural strength parameters and structural attenuation coefficient, and inputting the structural strength parameters and structural attenuation coefficient into the modified Mohr-Coulomb criterion to obtain the revised values ​​of soil layer parameters for different soil layer types in each excavation step; determining the soil stability of the lock pit by combining the revised values ​​of soil layer parameters for different soil layer types in each excavation step, and outputting the lock pit's anti-surge judgment result.

[0014] According to another aspect of the present invention, a calculation device for anti-surge intrusion of a lock foundation pit based on finite element analysis is also provided, comprising: a model calling unit for calling a three-dimensional fluid-structure coupled finite element model of the lock foundation pit, wherein the three-dimensional fluid-structure coupled finite element model is used to simulate the interaction between groundwater seepage pressure and soil deformation of the target lock; an excavation step elevation acquisition unit for acquiring elevation information of multiple excavation steps during the excavation process of the lock foundation pit; a stress calculation unit for inputting the elevation information into the three-dimensional fluid-structure coupled finite element model and calculating stress parameters of different soil layer types in each excavation step through the three-dimensional fluid-structure coupled finite element model; and a soil stability analysis unit for analyzing the stress parameters of different soil layer types in each excavation step using a predetermined shear stress detection criterion, determining the soil stability of the lock foundation pit, and outputting the anti-surge intrusion judgment result of the lock foundation pit.

[0015] According to another aspect of the present invention, a computer-readable storage medium is also provided, the computer-readable storage medium including a stored computer program, wherein, when the computer program is executed, it controls the device where the computer-readable storage medium is located to execute the above-mentioned method for calculating anti-surge inrush in lock foundation pit based on finite element analysis.

[0016] According to another aspect of the present invention, an electronic device is also provided, including one or more processors and a memory, the memory being used to store one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors cause the one or more processors to implement the above-described method for calculating anti-surge inrush resistance of lock foundation pit based on finite element analysis.

[0017] According to another aspect of the present invention, a computer program product is also provided, including a computer program that, when executed by a processor, implements the steps of the calculation method for anti-surge inrush of a lock foundation pit based on finite element analysis as described above.

[0018] In this disclosure, a three-dimensional fluid-structure interaction finite element model of the lock foundation pit is invoked. The three-dimensional fluid-structure interaction finite element model is used to simulate the interaction between groundwater seepage pressure and soil deformation in the target lock. Elevation information of multiple excavation steps during the excavation of the lock foundation pit is obtained. The elevation information is input into the three-dimensional fluid-structure interaction finite element model, and the stress parameters of different soil layer types in each excavation step are calculated through the three-dimensional fluid-structure interaction finite element model. The stress parameters of different soil layer types in each excavation step are analyzed using a predetermined shear stress detection criterion to determine the soil stability of the lock foundation pit and output the anti-surge judgment result of the lock foundation pit.

[0019] In this disclosure, by introducing fluid-structure interaction finite element analysis and a predetermined shear stress detection criterion, the stress parameters of different soil types at different excavation stages of the lock foundation pit can be calculated, thereby completing the dynamic evolution simulation of the model, improving the accuracy of the lock foundation pit's anti-surge stability assessment, enhancing the adaptability to geological uncertainties and water level fluctuations, and improving construction safety. This solves the technical problem in related technologies where the change of soil stress cannot be analyzed when verifying the anti-surge stability of the lock foundation pit under confined water, resulting in potential safety hazards in the project. Attached Figure Description

[0020] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0021] Figure 1 This is a flowchart of an optional calculation method for anti-surge intrusion of a lock foundation pit based on finite element analysis according to an embodiment of the present invention;

[0022] Figure 2 This is a schematic diagram of an optional three-dimensional finite element mesh calculation model according to an embodiment of the present invention;

[0023] Figure 3(a) is a three-dimensional vertical displacement diagram of an optional excavation step elevation of -1.00m according to an embodiment of the present invention;

[0024] Figure 3(b) is a schematic diagram of the pressure head parameters for an optional excavation step elevation of -1.00m according to an embodiment of the present invention;

[0025] Figure 3(c) is a vertical displacement diagram of an optional excavation step elevation of -1.00m according to an embodiment of the present invention;

[0026] Figure 3(d) is a vertical stress diagram of an optional excavation step elevation of -1.00m according to an embodiment of the present invention;

[0027] Figure 3(e) is a schematic diagram of an optional excavation step elevation of -1.00m according to an embodiment of the present invention;

[0028] Figure 4(a) is a three-dimensional vertical displacement diagram of an optional excavation step elevation of -2.00m according to an embodiment of the present invention;

[0029] Figure 4(b) is a schematic diagram of the pressure head parameters for an optional excavation step elevation of -2.00m according to an embodiment of the present invention;

[0030] Figure 4(c) is a vertical displacement diagram of an optional excavation step elevation of -2.00m according to an embodiment of the present invention;

[0031] Figure 4(d) is a vertical stress diagram of an optional excavation step elevation of -2.00m according to an embodiment of the present invention;

[0032] Figure 4(e) is a schematic diagram of an optional excavation step elevation of -2.00m according to an embodiment of the present invention;

[0033] Figure 5(a) is a three-dimensional vertical displacement diagram of an optional excavation step elevation of -4.00m according to an embodiment of the present invention;

[0034] Figure 5(b) is a schematic diagram of the pressure head parameters for an optional excavation step elevation of -4.00m according to an embodiment of the present invention;

[0035] Figure 5(c) is a vertical displacement diagram of an optional excavation step elevation of -4.00m according to an embodiment of the present invention;

[0036] Figure 5(d) is a vertical stress diagram of an optional excavation step elevation of -4.00m according to an embodiment of the present invention;

[0037] Figure 5(e) is a schematic diagram of an optional excavation step elevation of -4.00m according to an embodiment of the present invention;

[0038] Figure 6(a) is a three-dimensional vertical displacement diagram of an optional excavation step elevation of -4.9m according to an embodiment of the present invention;

[0039] Figure 6(b) is a schematic diagram of the pressure head parameters for an optional excavation step elevation of -4.9m according to an embodiment of the present invention;

[0040] Figure 6(c) is a vertical displacement diagram of an optional excavation step elevation of -4.9m according to an embodiment of the present invention;

[0041] Figure 6(d) is a vertical stress diagram of an optional excavation step elevation of -4.9m according to an embodiment of the present invention;

[0042] Figure 6(e) is a schematic diagram of an optional excavation step elevation of -4.9m according to an embodiment of the present invention;

[0043] Figure 7 This is a schematic diagram of an optional finite element analysis-based anti-surge calculation device for a lock pit according to an embodiment of the present invention;

[0044] Figure 8 This is a hardware structure block diagram of an electronic device (or mobile device) that performs a calculation method for anti-surge intrusion in a lock pit based on finite element analysis according to an embodiment of the present invention. Detailed Implementation

[0045] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0046] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0047] To facilitate understanding of the present invention by those skilled in the art, some terms or nouns involved in the various embodiments of the present invention are explained below:

[0048] Finite Element Analysis (FEA) discretizes a continuum into a finite number of elements and uses numerical calculations to solve for the distribution of soil displacement, stress, and strain, thereby simulating the entire process of resisting sudden surges in a lock pit.

[0049] Vertical displacement (VD) reflects the amount of soil deformation along the direction of gravity under excavation unloading. It is used to identify the rebound area and deformation concentration area at the bottom of the pit and to judge the stability trend of the soil.

[0050] Pressure head (PH) represents the hydrostatic pressure height of confined water at a certain point. It is a key parameter for calculating the jacking force of confined water and directly affects the effective stress state of the soil.

[0051] Vertical stress (VS) is the internal force that soil bears in the vertical direction. Tensile stress is negative and compressive stress is positive. The process of transitioning from compression to tension is an important indicator of a sudden surge.

[0052] Shear stress (SS) is the tangential stress generated by the relative sliding tendency between particles within the soil. Its value is compared with the shear strength of the soil to determine whether shear failure has occurred.

[0053] The Young's Modulus is a parameter that measures the ability of soil to resist elastic deformation and determines the stress-strain relationship.

[0054] Poisson's ratio describes the ratio of lateral deformation to longitudinal deformation of soil under stress, and affects the stress field distribution and the overall stiffness response of the soil.

[0055] Cohesion, the internal cohesion between soil particles, is an important component of shear strength, and plays a crucial role in the structural stability of cohesive soils.

[0056] The angle of internal friction is a parameter that reflects the frictional resistance between soil particles and determines the soil's resistance to sliding under shear loads.

[0057] The permeability coefficient is a parameter that characterizes the ability of soil to allow water to pass through it. It is used to calculate the distribution of the seepage field and the evolution of hydraulic head in confined water.

[0058] The Mohr-Coulomb Criterion (MC) is a strength theory describing soil shear failure. It uses cohesion and internal friction angle as parameters to determine whether shear stress exceeds the limit.

[0059] It should be noted that in this disclosure, customer information is collected and analyzed, and users are provided with corresponding operation entry points to choose whether to agree to or reject the automated decision results; if the user chooses to reject, the process will proceed to the expert decision-making process.

[0060] The following embodiments of the present invention can be applied to various systems / applications / equipment for calculating the anti-surge of lock foundation pits based on finite element analysis. For example, they are suitable for large-scale deep foundation pit engineering scenarios in high-water areas such as riverbanks, coastal areas, and waterway hubs, including lock foundation pits, port and wharf foundation pits, and waterway hub foundation pits. The present invention, by introducing fluid-structure interaction finite element analysis and a modified Mohr-Coulomb shear failure criterion, achieves dynamic evolution simulation of the stress-strain-shear stress state of the impermeable layer in the foundation pit under the action of confined water. This improves the scientific accuracy and precision of the anti-surge stability assessment, effectively reduces the overly conservative design caused by the traditional pressure balance method, reduces unnecessary reinforcement work, saves construction costs, and enhances the adaptability to geological uncertainties and water level fluctuations, thereby improving construction safety and design economy.

[0061] The present invention will now be described in detail with reference to various embodiments.

[0062] Example 1

[0063] According to an embodiment of the present invention, an embodiment of a calculation method for anti-surge inrush in lock pit based on finite element analysis is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0064] Figure 1 This is a flowchart of an optional calculation method for anti-surge inrush in a lock pit based on finite element analysis according to an embodiment of the present invention, such as... Figure 1 As shown, the method includes the following steps S101 to S104. The present invention will be described below in conjunction with each implementation step.

[0065] Optionally, before calling the three-dimensional fluid-structure interaction finite element model of the lock pit, the process includes: acquiring regional data of the lock pit before excavation; modeling the excavation area based on the regional data and fluid-structure interaction analysis principles, and outputting basic model parameters, including: top elevation, bottom elevation, ground elevation, and basic model coordinate axes, with the ground elevation being the boundary between the confined aquifer and the impermeable layer; determining the bottom of the model based on the bottom elevation and ground elevation, and setting the bottom of the model as the fixed constraint boundary; determining the horizontal symmetric constraint boundary of the model based on the bottom elevation, top elevation, and surrounding cut-off positions; determining the top elevation of the confined aquifer and the pressure head height of the confined aquifer based on the pre-acquired confined aquifer location information and geological survey report, to determine the seepage boundary around the model; and generating a three-dimensional fluid-structure interaction finite element model of the lock pit based on the fixed constraint boundary, the horizontal symmetric constraint boundary, and the seepage boundary around the model.

[0066] This embodiment acquires regional data of the lock pit, including but not limited to topography, geological borehole profiles, groundwater level monitoring records, and engineering layout plans, providing a spatial and physical information foundation for subsequent modeling. Then, based on the regional data of the lock pit and the principles of fluid-structure interaction analysis, preliminary geometric and boundary conditions are defined for the excavation area, which helps to construct a three-dimensional numerical model that conforms to the actual engineering scale and geological distribution. Optionally, the basic parameters of the model in this embodiment may include top elevation, bottom elevation, stratum elevation, and model foundation coordinate axes. The stratum elevation is the boundary between the confined aquifer and the impermeable layer. This parameter directly affects the starting position of the confined water's supporting effect, helping to accurately delineate the coupling interface between the seepage field and the stress field.

[0067] Furthermore, based on the bottom elevation and the stratum elevation, this embodiment determines the vertical boundary position of the model bottom and sets this boundary as a fixed constraint boundary to simulate the rigid blocking effect of the lower impermeable layer on soil deformation. This helps limit the overall displacement of the model bottom during excavation and unloading, making the calculation results closer to the actual stratum constraint conditions. Based on the bottom elevation, top elevation, and the surrounding interception positions, this embodiment determines the horizontal boundary range of the model and sets the two side boundaries of the model as horizontally symmetrical constraint boundaries. This reduces the computational domain size and simulates the mechanical state where soil displacement tends to zero far from the foundation pit area, which helps reduce computational resource consumption and improve numerical convergence stability.

[0068] It should be noted that this embodiment extracts the top elevation of the confined aquifer and the pressure head of the confined water as the core input parameters for the seepage boundary conditions. These parameters define the seepage boundary around the model, ensuring that the head distribution is consistent with the actual hydrogeological conditions. This helps to accurately reflect the distribution characteristics of the pressure distribution of confined water on the foundation pit floor. Based on the model's fixed constraint boundary, horizontal symmetric constraint boundary, and seepage boundary around the model, this embodiment generates a three-dimensional fluid-structure interaction finite element model of the lock foundation pit. This model integrates the soil deformation boundary and the groundwater flow boundary.

[0069] Optionally, after generating the three-dimensional fluid-structure coupled finite element model of the lock pit, the method further includes: determining the various soil types to be filled in the lock pit based on the geological survey report obtained after the investigation of the lock pit; obtaining the elastic modulus, soil density, soil Poisson's ratio, cohesion, internal friction angle and permeability coefficient corresponding to each soil type, and obtaining the relevant calculation parameters of the soil.

[0070] This embodiment, based on the geological survey report obtained after investigating the lock pit, identifies and classifies various soil layers to be filled within the pit area, including clay, sand, high-pressure jet grouting, grout, and concrete structural layers. This helps to clarify the spatial distribution and physical property differences of each soil layer. Furthermore, based on the indoor test data and in-situ test results of each soil layer in the geological survey report, this embodiment obtains the elastic modulus, soil density, Poisson's ratio, cohesion, internal friction angle, and permeability coefficient for each soil layer type, forming a complete set of calculation parameters related to the soil layers. Among these, the elastic modulus characterizes the stiffness response of the soil in the elastic stage; cohesion and internal friction angle are used to construct shear failure criteria; the permeability coefficient controls the conduction capacity of the seepage field; soil density participates in the calculation of volume forces and effective stress; and Poisson's ratio affects the lateral distribution characteristics of the stress field. These parameters collectively constitute the input basis for the finite element analysis.

[0071] It should be noted that this embodiment adopts a differentiated parameter value strategy for different soil types. For example, the resilient modulus is used as the Young's modulus for clay layers, 1.5 times the deformation modulus is used as the elastic modulus for sandy soil layers, and the high-pressure shotcrete reinforced soil and grout are set according to the test values ​​of similar projects. The concrete parameters are taken according to the specifications. This approach helps to match the actual deformation and strength characteristics of different materials under excavation disturbance, making the response of the numerical model in multi-layer heterogeneous strata closer to the field behavior.

[0072] Step S101: Call the three-dimensional fluid-structure interaction finite element model of the lock foundation pit, wherein the three-dimensional fluid-structure interaction finite element model is used to simulate the interaction between groundwater seepage pressure and soil deformation of the target lock.

[0073] In practical applications, this embodiment can utilize a three-dimensional fluid-structure interaction finite element model of the lock pit. This model, based on fluid-structure interaction theory, can simultaneously solve the stress-strain field of the soil and the seepage-head field of groundwater, enabling bidirectional interactive simulation between changes in confined water pressure and soil displacement response. The model treats the soil as a porous medium, assigning each soil layer an independent permeability coefficient and constitutive relation. This allows the increase in pore water pressure caused by rising water pressure to dynamically alter the effective stress of the soil, thereby inducing soil deformation. This soil deformation, in turn, affects the geometry of the seepage channels and the hydraulic gradient distribution, helping to realistically reproduce the coupled evolution process of soil rebound, head rise, and stress redistribution during pit excavation.

[0074] Step S102: Obtain elevation information for multiple excavation steps during the excavation of the lock foundation pit.

[0075] Optionally, the step of obtaining elevation information of multiple excavation steps in the process of excavating the lock foundation pit includes: dividing the foundation pit excavation process into multiple excavation steps based on the soil-related calculation parameters of various soil types in the lock foundation pit; determining the corresponding foundation pit excavation elevation information and foundation pit bottom elevation information for each excavation step, thereby obtaining the elevation information of multiple excavation steps.

[0076] Based on the relevant calculation parameters of various soil types in the lock pit, this embodiment divides the pit excavation process into multiple excavation steps, combining the stratum boundary elevation and the top elevation of the confined aquifer. This ensures that the boundary of each excavation step is coordinated with the key soil layer interface (such as the boundary between clay and sand layers), which helps to accurately capture the stress redistribution characteristics when different soil stiffness and permeability switch in numerical simulation, and avoids missing key mechanical response nodes due to overly coarse division of excavation steps.

[0077] Furthermore, in this embodiment, the corresponding excavation elevation information and the bottom elevation information of the foundation pit are determined for each excavation step. For example, in the planned lock foundation pit project, the excavation elevation gradually increases from -1.00m to -4.90m in increments of 0.5m to 1.0m, ensuring that each excavation step can reflect the stage-by-stage cumulative effect of soil unloading and the pressure of the pressurized water. The bottom elevation information of the foundation pit is used as the final excavation target to define the stress concentration area and tensile stress formation range at the bottom of the model. This step-by-step setting method can systematically track the gradual change trend of vertical displacement growth, the critical point of stress conversion from compression to tension, and the shear stress level.

[0078] Step S103: Input the elevation information into the three-dimensional fluid-structure interaction finite element model, and calculate the stress parameters of different soil layer types in each excavation step through the three-dimensional fluid-structure interaction finite element model.

[0079] Optionally, the steps of inputting elevation information into a three-dimensional fluid-structure interaction finite element model and calculating stress parameters for different soil layer types at each excavation step using the three-dimensional fluid-structure interaction finite element model include: meshing the three-dimensional fluid-structure interaction finite element model according to a preset soil meshing precision and outputting a model mesh element set; inputting the elevation information corresponding to each excavation step and the soil layer-related calculation parameters corresponding to each soil layer type into the three-dimensional fluid-structure interaction finite element model, and using the model mesh element set to perform simulation evolution operations on the displacement field and stress field of each excavation step; during the simulation evolution process, calculating the vertical displacement, pressure head, vertical stress, and shear stress values ​​for each soil layer type to obtain the stress parameters for different soil layer types at each excavation step.

[0080] This embodiment meshes the three-dimensional fluid-structure interaction finite element model according to a preset soil meshing precision. For example, the mesh element size is controlled to be 0.5m or less, allowing for sufficient analysis of key stress gradient regions near the confined aquifer top, impermeable layer interface, and excavation face. The resulting model mesh element set helps improve the calculation accuracy of local stress concentration and shear stress evolution paths. Furthermore, this embodiment inputs the elevation information corresponding to each excavation step and the soil-related calculation parameters corresponding to each soil type into the three-dimensional fluid-structure interaction finite element model. Combined with the model mesh element set, the simulation evolution operations of displacement and stress fields are executed step by step. This ensures that the boundary condition updates of each excavation step are collaboratively driven by the soil parameters to propel the finite element solver, achieving coupled iterative calculation of seepage-consolidation-shear. During the simulation evolution process, this embodiment synchronously outputs the vertical displacement, pressure head, vertical stress, and shear stress values ​​for each soil layer type. The vertical displacement reflects the rebound trend of the soil, the pressure head characterizes the strength of the confined water support, the vertical stress identifies the critical point of the compression-tension transition, and the shear stress assesses the reserve state of shear strength. Finally, a set of stress parameters for different soil layer types under each excavation step is formed, which helps to construct a multi-dimensional and hierarchical stability assessment basis.

[0081] Optionally, during the simulation evolution process, the steps of calculating the vertical displacement, pressure head, vertical stress, and shear stress values ​​of each soil layer type to obtain the stress parameters of different soil layer types in each excavation step include: extracting the maximum shear stress component of all soil layer types at the Gaussian point of the soil in each excavation step; generating a three-dimensional shear stress field distribution map based on the maximum shear stress component through spatial interpolation; determining the shear stress value of each soil layer type based on the three-dimensional shear stress field distribution map; and storing the three-dimensional shear stress field distribution map in the storage module of the three-dimensional fluid-structure interaction finite element model in the form of isosurfaces and slices.

[0082] In this embodiment, the maximum shear stress component at the Gaussian point of the soil is extracted for all soil types in each excavation step. This component is calculated by the finite element solver at the integration point based on the principal direction of the stress tensor, which helps to capture local stress concentration areas of potential shear failure surfaces within the soil, ensuring that the calculation results are not limited to element average values. Furthermore, based on the extracted maximum shear stress components at each Gaussian point, this embodiment reconstructs a continuous three-dimensional shear stress field distribution map using spatial interpolation algorithms (such as trilinear interpolation or Kriging interpolation). This transforms the discrete integration point data into a continuous stress field covering the entire model domain, helping to reveal the spatial evolution of shear stress in key areas such as the top of the impermeable layer, the edge of the excavation face, and the periphery of the jet grouting piles.

[0083] It should be noted that this embodiment, based on a three-dimensional shear stress field distribution map and combined with spatial zoning information of soil layer types, statistically extracts and analyzes shear stress values ​​for each type of soil region, distinguishing the shear stress response characteristics of different materials such as clay, sand, and reinforced soil, thus giving the shear stress values ​​of each soil layer a clear physical property attribution. Furthermore, this embodiment stores the three-dimensional shear stress field distribution map in the storage module of the three-dimensional fluid-structure interaction finite element model in the form of isosurfaces and slices. The isosurfaces present the connected shape of high shear stress areas, and the slices show the stress gradient distribution in vertical or horizontal profiles. This storage method facilitates rapid retrieval of shear stress evolution characteristics under historical conditions in subsequent sensitivity analysis or design optimization, and supports multi-condition comparative analysis and visualization verification of calculation results.

[0084] Step S104: Analyze the stress parameters of different soil types in each excavation step using a predetermined shear stress detection criterion, determine the soil stability of the lock pit, and output the lock pit anti-surge judgment result.

[0085] Optionally, the steps of analyzing the stress parameters of different soil layer types at each excavation step using a predetermined shear stress testing criterion, determining the soil stability of the lock pit, and outputting the lock pit's anti-surge judgment result include: conducting sensitivity analysis on the non-uniformity of stratum distribution, the non-uniformity of soil shear strength index, and the change of confined hydraulic head based on the stress parameters of different soil layer types at each excavation step; selecting the modified Mohr-Coulomb criterion as the predetermined shear stress testing criterion based on the sensitivity analysis results and the structural characteristics of each soil layer type; obtaining the structural strength parameters and structural attenuation coefficient, and inputting the structural strength parameters and structural attenuation coefficient into the modified Mohr-Coulomb criterion to obtain the revised values ​​of soil layer parameters for different soil layer types at each excavation step; determining the soil stability of the lock pit by combining the revised values ​​of soil layer parameters for different soil layer types at each excavation step, and outputting the lock pit's anti-surge judgment result.

[0086] In this embodiment, the unevenness of the stratum distribution can be calculated based on the stress parameters of different soil layer types at each excavation step. By adjusting the elevation of the top plate of the confined aquifer within the allowable deviation range of the survey report, the impact of local thinning or thickening of the aquitard on the shear stress transmission path can be simulated. At the same time, the unevenness of the soil shear strength index can be calculated in multiple scenarios. For example, the average, characteristic, and minimum values ​​of cohesion and internal friction angle can be used as input parameters to reflect the spatial variability of soil parameters. For example, for the change of confined water head, the water head height can be increased or decreased in 1m increments according to the water level fluctuation range during the flood season and the dry season to analyze the sensitivity of water pressure changes to shear stress accumulation. Sensitivity analysis helps to construct a multi-dimensional risk boundary. Furthermore, in this embodiment, the predetermined shear stress detection criterion is selected as the modified Mohr-Coulomb criterion. This criterion introduces structural strength parameters and structural attenuation coefficients to characterize the mechanical behavior of cemented clay as it gradually deteriorates from an intact structure to a damaged state under the coupled action of unloading and seepage. It is applicable to the engineering scenario in this embodiment where the clay layer is the confined impermeable layer, and helps to overcome the limitation of the traditional Mohr-Coulomb criterion in ignoring the structural failure of the soil.

[0087] It should be noted that this embodiment obtains structural strength parameters and structural attenuation coefficients. The structural strength parameters include the initial cohesion and internal friction angle under intact structural conditions, as well as the strength degradation amplitude caused by structural damage. The structural attenuation coefficient is determined based on field sampling tests or similar engineering experience, and its value range can be set from 0 to 1, where 0 indicates no structural damage and 1 indicates complete loss of cohesion. These parameters are input into the modified Mohr-Coulomb criterion to achieve dynamic correction of the ultimate shear stress, allowing the shear strength to adaptively decrease with the degree of soil structural damage. Finally, this embodiment combines the revised soil layer parameter values ​​for different soil types at each excavation step with the actual calculated shear stress value and the corrected ultimate shear stress value. When the maximum shear stress in all excavation steps is less than the corrected ultimate shear stress of the corresponding soil layer, it is determined to be stable against inrush, and the output judgment result is "no inrush risk." Through the synergistic constraint of structural evolution mechanism and parameter uncertainty, the judgment result has mechanical mechanism support and engineering adaptability.

[0088] Through the above steps, a three-dimensional fluid-structure interaction finite element model of the lock pit can be invoked. The three-dimensional fluid-structure interaction finite element model is used to simulate the interaction between groundwater seepage pressure and soil deformation in the target lock. Elevation information of multiple excavation steps during the excavation of the lock pit can be obtained. The elevation information is input into the three-dimensional fluid-structure interaction finite element model, and the stress parameters of different soil layer types in each excavation step are calculated through the three-dimensional fluid-structure interaction finite element model. The stress parameters of different soil layer types in each excavation step are analyzed using a predetermined shear stress detection criterion to determine the soil stability of the lock pit and output the anti-surge judgment result of the lock pit. In this embodiment, by introducing fluid-structure interaction finite element analysis and a predetermined shear stress detection criterion, the stress parameters of different soil types at different excavation steps of the lock foundation pit can be calculated, thereby completing the dynamic evolution simulation of the model, improving the accuracy of the lock foundation pit's anti-surge stability assessment, enhancing the adaptability to geological uncertainties and water level fluctuations, and improving construction safety. This solves the technical problem in related technologies where the change of soil stress cannot be analyzed when verifying the anti-surge stability of the lock foundation pit under confined water, resulting in potential safety hazards in the project.

[0089] The following describes in detail another optional implementation method.

[0090] This invention proposes a calculation method for resisting sudden surge of confined water in lock foundation pits based on finite element analysis. Taking the Weishan Third Line Lock foundation pit project as an example, the control method is explained.

[0091] Step S1: Establish a finite element model based on fluid-structure interaction theory.

[0092] Based on the general principles and characteristics of fluid-structure interaction (FSI) computational analysis, and considering the actual conditions of the foundation pit, a detailed model of the excavation area is performed during the calculation. Taking the modeling of the Weishan Three-Line Ship Lock foundation pit project as an example... Figure 2 This is a schematic diagram of an optional three-dimensional finite element mesh calculation model according to an embodiment of the present invention. Figure 2 In the model, the top elevation is 4.00 m (original ground level), and the bottom elevation is -50.00 m (elevation of the bottom impermeable layer). The ground elevation of -10.85 m is the boundary between the sand layer (confined aquifer) and the clay layer (impermeable layer). The model's X-axis boundary is -138.00 m to 138.00 m (20 m outside the top of the slope, determined according to slope stability and construction traffic requirements), and the Y-axis boundary is -81.00 m to 89.00 m (20 m outside the top of the slope).

[0093] Step S2: Set boundary conditions, calculation parameters, and calculation conditions.

[0094] (1) The boundary conditions around the calculation area are assumed to be: 1) Displacement boundary: The bottom of the model is a fixed constraint boundary, and the surrounding area is a horizontal symmetrical constraint boundary. 2) The seepage boundary around the model is determined by the known confined water. According to the geological survey report of the Weishan Three-Line Ship Lock Pit Project, the top elevation of the confined water layer is -10.85m, corresponding to a pressure head of 12.38m.

[0095] (2) Calculate the parameters.

[0096] The mechanical and seepage parameters of various materials used in the calculations are mainly based on the geological survey report and selected by comprehensively considering engineering experience, as shown in Table 1 below. It should be noted that this embodiment considers the lock excavation condition; the resilient modulus is used as the elastic modulus for the clay layer, i.e., E=Er=15MPa; 1.5 times the deformation modulus is used as the elastic modulus for the sand layer, i.e., E=1.5. E0=45Mpa; the soil reinforced by high-pressure jet grouting uses the test value of 72Mpa from similar projects; the elastic modulus of concrete uses the value specified in the standard.

[0097] Table 1 Relevant Calculation Parameters

[0098]

[0099] (3) Calculate the working conditions.

[0100] According to Article C.0.1 of the "Technical Specification for Foundation Pit Support" (JGJ 120-2012), the stability of the pit bottom under the action of confined water was verified. When the excavation elevation of the foundation pit is above -1.0m, there is no risk of sudden heave. To reduce the workload of finite element calculation, a step-by-step excavation calculation method was adopted based on the characteristics of the foundation pit. The calculation was divided into 5 steps, with corresponding foundation pit excavation elevations of -1.00m, -2.00m, -3.00m, -4.00m, and -4.90m (foundation pit bottom elevation).

[0101] Step S3: Divide the computational grid.

[0102] The soil mesh division accuracy is 0.5m. Taking the Weishan Third Line Ship Lock foundation pit project as an example, a total of 156,326 nodes and 147,612 units were generated.

[0103] Step S4: 3D finite element calculation results and analysis.

[0104] The calculations include vertical displacement, pressure head, vertical stress, and shear stress values ​​of each soil layer, as well as the evolution of displacement and stress fields at each excavation step. The following example, using the Weishan Third Line Ship Lock foundation pit project, illustrates the vertical displacement, pressure head, vertical stress, and shear stress values ​​of each soil layer.

[0105] Figure 3(a) illustrates the three-dimensional vertical displacement diagram at an excavation step elevation of -1.00m. This displacement diagram is derived from a finite element model established using fluid-structure interaction theory. In Figure 3(a), the values ​​are positive at the top and negative at the bottom. Figure 3(b) illustrates the pressure head parameters at an excavation step elevation of -1.00m. Figure 3(c) illustrates the vertical displacement diagram at an excavation step elevation of -1.00m. Figure 3(d) illustrates the vertical stress diagram at an excavation step elevation of -1.00m (with positive tension and negative compressive stress in Figure 3(d)). Figure 3(e) illustrates the shear stress level at an excavation step elevation of -1.00m.

[0106] Figure 4(a) illustrates the three-dimensional vertical displacement diagram at an excavation step elevation of -2.00m. This displacement diagram is derived from a finite element model established using fluid-structure interaction theory. In Figure 4(a), the values ​​are positive at the top and negative at the bottom. Figure 4(b) illustrates the pressure head parameters at an excavation step elevation of -2.00m. Figure 4(c) illustrates the vertical displacement diagram at an excavation step elevation of -2.00m. Figure 4(d) illustrates the vertical stress diagram at an excavation step elevation of -2.00m (with negative tension and positive compression in Figure 4(d)). Figure 4(e) illustrates the shear stress level at an excavation step elevation of -2.00m.

[0107] It should be noted that this embodiment does not show schematic diagrams of various stress parameters at an excavation step elevation of -3.00m.

[0108] Figure 5(a) illustrates the three-dimensional vertical displacement diagram at an excavation step elevation of -4.00m. This displacement diagram is derived from a finite element model established using fluid-structure interaction theory. In Figure 5(a), the values ​​are positive at the top and negative at the bottom. Figure 5(b) illustrates the pressure head parameters at an excavation step elevation of -4.00m. Figure 5(c) illustrates the vertical displacement diagram at an excavation step elevation of -4.00m. Figure 5(d) illustrates the vertical stress diagram at an excavation step elevation of -4.00m (with negative tension and positive compression in Figure 5(d)). Figure 5(e) illustrates the shear stress level at an excavation step elevation of -4.00m.

[0109] Figure 6(a) illustrates the three-dimensional vertical displacement diagram at an excavation step elevation of -4.9m. This displacement diagram is derived from a finite element model established using fluid-structure interaction theory. In Figure 6(a), the values ​​are positive at the top and negative at the bottom. Figure 6(b) illustrates the pressure head parameters at an excavation step elevation of -4.9m. Figure 6(c) illustrates the vertical displacement diagram at an excavation step elevation of -4.9m. Figure 6(d) illustrates the vertical stress diagram at an excavation step elevation of -4.9m (with negative tension and positive compression in Figure 6(d)). Figure 6(e) illustrates the shear stress level at an excavation step elevation of -4.9m.

[0110] The calculation results for each working condition are shown in Table 2.

[0111] Table 2. Statistical Table of Vertical Displacement and Tensile Stress under Various Excavation Conditions

[0112]

[0113] Taking the Weishan Third-Line Ship Lock foundation pit project as an example, simulation results show that with the increase of excavation unloading depth, the rebound deformation of the soil at the bottom of the pit is significant, and the peak vertical displacement increases from 9.48 cm to 12.30 cm. Simultaneously, the minimum vertical stress undergoes a transition from compression to tension (from 15.59 kPa to -7.21 kPa). At an excavation elevation of -4.9 m, significant tensile stress concentration occurs in the top plate of the confined layer and the surrounding area of ​​the excavation face. The formation mechanism of this tensile stress zone is that the surface soil is mainly driven by rebound deformation, while the top of the confined layer is controlled by the pressure from the confined water and the sudden drop in effective stress caused by the removal of the overlying load.

[0114] Step S5: Sensitivity analysis.

[0115] Due to the uneven distribution of geological strata and the unevenness of soil shear strength indices, and considering the seasonal variation of confined water head, a sensitivity analysis is required on the calculation results of step S4. After the sensitivity analysis, if the average value is used as the evaluation standard, a safety factor of 1.1-1.3 can be reserved, the specific amount of which can be determined based on practical experience in the engineering area.

[0116] It should be noted that the heterogeneity of the strata distribution can be determined based on the nearby borehole data in the geological survey report, and can be calculated by trial calculations from low to high according to the top elevation of the confined aquifer. The heterogeneity of the soil shear strength index can be determined based on the soil shear strength index in the geological survey report, and generally requires trial calculations of the average value, characteristic value, and minimum value.

[0117] In addition, the change of the confined water head with the season can be calculated according to the water head between the flood season and the dry season. In this embodiment, the calculation can be performed in 1m increments.

[0118] Step S6: Determine the failure criteria of the soil at the bottom of the pit and assess the anti-surge stability of the lock foundation pit project.

[0119] When determining the failure criterion for soil structures, it is necessary to consider the structural characteristics of the soil (cementation, porosity, particle arrangement), stress state, and engineering conditions. This should be achieved through a three-step method: theoretical derivation, laboratory testing, and field verification. The final criterion should quantitatively describe the entire process of soil failure from elastic deformation to structural damage and ultimately overall instability, while also being compatible with the three key characteristics of soil structural failure: gradualism, anisotropy, and stress path correlation. The overlying impermeable layer is cohesive soil with strong cementation and structure. The initial failure of cemented structural soil is characterized by a sudden drop in strength, requiring a focus on the structural yield stress. In this embodiment, a modified Mohr-Coulomb criterion is adopted.

[0120] Basic framework: Mohr-Coulomb shear stress failure criterion ;in, For the shear stress of the soil, The normal stress parameter of the soil is given.

[0121] Structural Correction: Introducing structural strength parameters and structural attenuation coefficient D (0≤D≤1, D=0 for intact structure, D=1 for complete structural failure), the corrected structure is as follows: ,in , The cohesion and internal friction angle of the intact soil structure. , D represents the magnitude of strength degradation caused by structural damage, and D is the structural attenuation coefficient.

[0122] Taking the Weishan Third Line Ship Lock foundation pit project as an example, the calculation results in Table 2 above show that when the excavation reaches -4.9m, although there is local tensile stress, the shear stress level (0.21-0.35) throughout the process is always much less than the ultimate state of 1.0, indicating that the soil has sufficient shear strength reserves, no shear instability has occurred, and there is no risk of sudden water inrush.

[0123] The above embodiments, by introducing a three-dimensional finite element analysis framework based on fluid-structure interaction, achieve a refined simulation of the entire process of soil deformation and the interaction of confined water pressure during foundation pit excavation. This can objectively reflect the vertical displacement evolution, stress redistribution, and shear stress accumulation characteristics of the soil under the combined action of unloading and water pressure support. This breaks through the simplified assumption of the traditional pressure balance method that only relies on the weight-water head ratio, and makes the judgment of anti-surge stability based on the real stress-strain response.

[0124] Furthermore, by constructing a multi-condition step-by-step excavation simulation mechanism, combined with high-precision grid division and differentiated assignment of soil layer parameters, this invention can accurately capture the formation and development process of tensile stress in the top plate area of ​​the impermeable layer, as well as the spatial distribution law of shear stress at the interface of clay layer, sand layer and reinforced structure, providing visualized and quantifiable data support for identifying potential instability areas.

[0125] This invention employs sensitivity analysis to systematically cover formation heterogeneity, shear strength parameter variability, and seasonal fluctuations in confined hydraulic head, enabling stability assessment results to accommodate uncertainties in geological and hydrological conditions and effectively reducing engineering redundancy caused by single or conservative parameter settings.

[0126] This invention introduces a modified Mohr-Coulomb criterion, which integrates soil structural strength parameters and structural attenuation coefficients to couple shear strength determination with the soil cementation degradation process. This enables the simulation of progressive failure from elastic deformation to structural failure, improves the applicability of the criterion to cemented clay impermeable layers, and avoids the underestimation or neglect of soil shear strength reserves by traditional methods.

[0127] The following is a detailed description with reference to another embodiment.

[0128] Example 2

[0129] The anti-surge calculation device for lock pit based on finite element analysis provided in this embodiment includes multiple implementation units, each of which corresponds to a specific implementation step in the above embodiment one.

[0130] Figure 7 This is a schematic diagram of an optional finite element analysis-based anti-surge calculation device for lock foundation pits according to an embodiment of the present invention, as shown below. Figure 7 As shown, the anti-surge calculation device for lock pit foundation pit based on finite element analysis may include: model calling unit 71, excavation step elevation acquisition unit 72, stress calculation unit 73, and soil stability analysis unit 74.

[0131] Among them, the model calling unit 71 is used to call the three-dimensional fluid-structure coupled finite element model of the lock foundation pit. The three-dimensional fluid-structure coupled finite element model is used to simulate the interaction between the groundwater seepage pressure and soil deformation of the target lock.

[0132] The excavation step elevation acquisition unit 72 is used to acquire elevation information of multiple excavation steps during the excavation of the lock foundation pit.

[0133] The stress calculation unit 73 is used to input elevation information into the three-dimensional fluid-structure interaction finite element model and calculate the stress parameters of different soil layer types in each excavation step through the three-dimensional fluid-structure interaction finite element model.

[0134] The soil stability analysis unit 74 is used to analyze the stress parameters of different soil layer types in each excavation step using a predetermined shear stress detection criterion, determine the soil stability of the lock pit, and output the lock pit anti-surge judgment result.

[0135] The aforementioned calculation device for anti-surge intrusion of the lock foundation pit based on finite element analysis can call the three-dimensional fluid-structure coupled finite element model of the lock foundation pit through the model calling unit 71. The three-dimensional fluid-structure coupled finite element model is used to simulate the interaction between groundwater seepage pressure and soil deformation of the target lock. The elevation information of multiple excavation steps in the excavation process of the lock foundation pit is obtained through the excavation step elevation acquisition unit 72. The elevation information is input into the three-dimensional fluid-structure coupled finite element model through the stress calculation unit 73. The stress parameters of different soil layer types in each excavation step are calculated through the three-dimensional fluid-structure coupled finite element model. The stress parameters of different soil layer types in each excavation step are analyzed by the soil stability analysis unit 74 using a predetermined shear stress detection criterion to determine the soil stability of the lock foundation pit and output the anti-surge judgment result of the lock foundation pit. In this embodiment, by introducing fluid-structure interaction finite element analysis and a predetermined shear stress detection criterion, the stress parameters of different soil types at different excavation steps of the lock foundation pit can be calculated, thereby completing the dynamic evolution simulation of the model, improving the accuracy of the lock foundation pit's anti-surge stability assessment, enhancing the adaptability to geological uncertainties and water level fluctuations, and improving construction safety. This solves the technical problem in related technologies where the change of soil stress cannot be analyzed when verifying the anti-surge stability of the lock foundation pit under confined water, resulting in potential safety hazards in the project.

[0136] Optionally, the finite element analysis-based anti-surge calculation device for lock foundation pits further includes: a lock foundation pit area data acquisition unit, used to acquire area data of the lock foundation pit before calling the three-dimensional fluid-structure interaction finite element model of the lock foundation pit and before carrying out the excavation operation of the lock foundation pit; a modeling unit, used to model the excavation area of ​​the foundation pit based on the area data of the lock foundation pit and the principles of fluid-structure interaction analysis, and output the basic parameters of the model, wherein the basic parameters of the model include: top elevation, bottom elevation, stratum elevation, and model foundation coordinate axes, and the stratum elevation is the boundary between the confined aquifer and the impermeable layer; and a first boundary determination unit, used for... The model bottom is determined based on the bottom elevation and the stratum elevation, and the bottom of the model is set as the fixed constraint boundary of the model. The second boundary determination unit is used to determine the horizontal symmetric constraint boundary of the model based on the bottom elevation, the top elevation, and the surrounding interception positions. The third boundary determination unit is used to determine the top elevation of the confined aquifer and the pressure head height of the confined aquifer based on the pre-acquired confined aquifer location information and the geological survey report, so as to determine the seepage boundary around the model. The model generation unit is used to generate a three-dimensional fluid-structure interaction finite element model of the lock pit based on the fixed constraint boundary, the horizontal symmetric constraint boundary, and the seepage boundary around the model.

[0137] Optionally, the calculation device for anti-surge inrush in lock foundation pit based on finite element analysis further includes: a soil type determination unit, used to determine the various soil types to be filled in the lock foundation pit based on the geological survey report obtained after the three-dimensional fluid-structure coupled finite element model of the lock foundation pit is generated; and a soil parameter acquisition module, used to obtain the elastic modulus, soil density, Poisson's ratio, cohesion, internal friction angle and permeability coefficient corresponding to each soil type, so as to obtain the relevant calculation parameters of the soil.

[0138] Optionally, the excavation step elevation acquisition unit includes: an excavation step division module, used to divide the excavation process of the lock pit into multiple excavation steps based on the relevant calculation parameters of soil layers of various soil types; and an excavation step elevation determination module, used to determine the corresponding excavation elevation information and bottom elevation information of the pit for each excavation step, thereby obtaining the elevation information of multiple excavation steps.

[0139] Optionally, the stress calculation unit includes: a mesh generation module, used to mesh the three-dimensional fluid-structure interaction finite element model according to a preset soil mesh generation precision, and output a model mesh element set; a model evolution module, used to input the elevation information corresponding to each excavation step and the soil-related calculation parameters corresponding to each soil layer type into the three-dimensional fluid-structure interaction finite element model, and use the model mesh element set to perform simulation evolution operations of the displacement field and stress field of each excavation step; and a soil layer stress calculation module, used to calculate the vertical displacement, pressure head, vertical stress, and shear stress values ​​of each soil layer type during the simulation evolution process, and obtain the stress parameters of different soil layer types for each excavation step.

[0140] Optionally, the soil stress calculation module includes: a shear stress component extraction module, used to extract the maximum shear stress component of all soil types at the Gaussian point of the soil in each excavation step; a shear stress field distribution map generation module, used to generate a three-dimensional shear stress field distribution map based on the maximum shear stress component through spatial interpolation; a shear stress value determination module, used to determine the shear stress value of each soil type based on the three-dimensional shear stress field distribution map; and a shear stress value storage module, used to store the three-dimensional shear stress field distribution map in the form of isosurfaces and slices in the storage module of the three-dimensional fluid-structure interaction finite element model.

[0141] Optionally, the soil stability analysis unit includes: a sensitivity analysis module, used to perform sensitivity analysis on the heterogeneity of stratum distribution, the heterogeneity of soil shear strength index, and the change of confined hydraulic head based on the stress parameters of different soil layer types in each excavation step; a criterion selection module, used to select a predetermined shear stress detection criterion as the modified Mohr-Coulomb criterion based on the sensitivity analysis results and the structural characteristics of each soil layer type; a soil layer parameter revision module, used to obtain structural strength parameters and structural attenuation coefficients, and input the structural strength parameters and structural attenuation coefficients into the modified Mohr-Coulomb criterion to obtain the revised values ​​of soil layer parameters for different soil layer types in each excavation step; and a lock pit anti-surge determination module, used to determine the soil stability of the lock pit by combining the revised values ​​of soil layer parameters for different soil layer types in each excavation step, and output the lock pit anti-surge determination results.

[0142] The aforementioned calculation device for anti-surge inrush in lock pits based on finite element analysis may also include a processor and a memory. The aforementioned model calling unit 71, excavation step elevation acquisition unit 72, stress calculation unit 73, soil stability analysis unit 74, etc., are all stored in the memory as program units, and the processor executes the aforementioned program units stored in the memory to realize the corresponding functions.

[0143] The aforementioned processor contains a kernel, which retrieves the corresponding program units from memory. One or more kernels can be configured, and the calculation of confined water inrush resistance in the lock pit based on finite element analysis can be achieved by adjusting the kernel parameters.

[0144] The aforementioned memory may include non-permanent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM, and the memory includes at least one memory chip.

[0145] According to another aspect of the present invention, a computer-readable storage medium is also provided, the computer-readable storage medium including a stored computer program, wherein, when the computer program is running, it controls the device where the computer-readable storage medium is located to execute any of the above-described methods for calculating the anti-surge of lock foundation pit based on finite element analysis.

[0146] According to another aspect of the present invention, an electronic device is also provided, including one or more processors and a memory, wherein the memory is used to store one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors cause the one or more processors to implement the finite element analysis-based calculation method for anti-surge intrusion in lock foundation pits as described in any of the embodiments of the present invention.

[0147] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the calculation method for anti-surge inrush of lock foundation pit based on finite element analysis described in various embodiments of this application.

[0148] This application also provides a computer program product, including a non-volatile computer-readable storage medium storing a computer program, which, when executed by a processor, implements the steps of the calculation method for anti-surge inrush of lock foundation pit based on finite element analysis described in various embodiments of this application.

[0149] Figure 8 This is a hardware structure block diagram of an electronic device (or mobile device) that performs a calculation method for anti-surge inrush in a lock pit based on finite element analysis, according to an embodiment of the present invention. Figure 8 As shown, an electronic device may include one or more ( Figure 8 The processor (which may include, but is not limited to, a microprocessor MCU or a programmable logic device FPGA, etc.) and memory 804 for storing data are also included. In addition, it may include: a display, an input / output interface (I / O interface), a universal serial bus (USB) port (which may be included as one of the ports of the I / O interface), a network interface, a keyboard, a power supply, and / or a camera. Those skilled in the art will understand that... Figure 8 The structure shown is for illustrative purposes only and does not limit the structure of the electronic device described above. For example, the electronic device may also include components that are more... Figure 8 The more or fewer components shown, or having the same Figure 8 The different configurations shown.

[0150] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0151] In the above embodiments of the present invention, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0152] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units can be a logical functional division, and in actual implementation, there may be other division methods. For instance, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling, direct coupling, or communication connection may be through some interfaces; the indirect coupling or communication connection between units or modules may be electrical or other forms.

[0153] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0154] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0155] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0156] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A calculation method for anti-surge inrush resistance of lock foundation pit based on finite element analysis, characterized in that, include: The three-dimensional fluid-structure interaction finite element model of the lock foundation pit is invoked, wherein the three-dimensional fluid-structure interaction finite element model is used to simulate the interaction between groundwater seepage pressure and soil deformation of the target lock. Obtain elevation information for multiple excavation steps during the excavation of the lock foundation pit; The elevation information is input into the three-dimensional fluid-structure interaction finite element model, and the stress parameters of different soil layer types in each excavation step are calculated through the three-dimensional fluid-structure interaction finite element model. The stress parameters of different soil layer types in each excavation step are analyzed using a predetermined shear stress detection criterion to determine the soil stability of the lock pit and output the lock pit anti-surge judgment result.

2. The calculation method for anti-surge inrush in lock foundation pits according to claim 1, characterized in that, Before calling the three-dimensional fluid-structure interaction finite element model of the lock foundation pit, the following is also included: Before carrying out the excavation of the lock foundation pit, obtain the regional data of the lock foundation pit; Based on the regional data of the lock pit and the principle of fluid-structure interaction analysis, the excavation area of ​​the pit is modeled and the basic parameters of the model are output. The basic parameters of the model include: top elevation, bottom elevation, stratum elevation and model foundation coordinate axis. The stratum elevation is the boundary between the confined aquifer and the impermeable layer. Based on the bottom elevation and the stratum elevation, the bottom of the model is determined, and the bottom of the model is set as the fixed constraint boundary of the model; Based on the bottom elevation, the top elevation, and the surrounding intercepted positions, the horizontal symmetry constraint boundary of the model is determined; Based on the pre-acquired information on the location of the confined aquifer and the geological survey report, the elevation of the top of the confined aquifer and the pressure head of the confined aquifer are determined to determine the seepage boundary around the model. Based on the fixed constraint boundary of the model, the horizontal symmetric constraint boundary of the model, and the seepage boundary around the model, the three-dimensional fluid-structure interaction finite element model of the lock pit is generated.

3. The calculation method for anti-surge inrush in lock foundation pit according to claim 2, characterized in that, After generating the three-dimensional fluid-structure interaction finite element model of the lock foundation pit, the following steps are also included: Based on the geological survey report obtained after the investigation of the lock foundation pit, the various soil layer types to be filled in the lock foundation pit were determined. The elastic modulus, soil density, Poisson's ratio, cohesion, internal friction angle, and permeability coefficient of each soil layer type are obtained to obtain the relevant calculation parameters of the soil layer.

4. The calculation method for anti-surge inrush resistance of the lock foundation pit according to claim 1, characterized in that, The steps for obtaining elevation information for multiple excavation steps during the lock pit excavation process include: Based on the soil-related calculation parameters of various soil types in the lock pit, the pit excavation process is divided into multiple excavation steps. For each excavation step, the corresponding foundation pit excavation elevation information and foundation pit bottom elevation information are determined to obtain the elevation information of the multiple excavation steps.

5. The calculation method for anti-surge inrush in lock foundation pit according to claim 1, characterized in that, The steps of inputting the elevation information into the three-dimensional fluid-structure interaction finite element model and calculating the stress parameters of different soil layer types at each excavation step using the three-dimensional fluid-structure interaction finite element model include: The three-dimensional fluid-structure interaction finite element model is meshed according to the preset soil meshing accuracy, and the model mesh element set is output. The elevation information corresponding to each excavation step and the soil-related calculation parameters corresponding to each soil layer type are input into the three-dimensional fluid-structure coupled finite element model, and the displacement field and stress field of each excavation step are simulated and evolved using the model mesh element set. During the simulation evolution process, the vertical displacement, pressure head, vertical stress, and shear stress values ​​of each soil layer type are calculated to obtain the stress parameters of different soil layer types for each excavation step.

6. The calculation method for anti-surge inrush in lock pits according to claim 5, characterized in that, The steps involved in the simulation evolution process, including calculating the vertical displacement, pressure head, vertical stress, and shear stress values ​​for each soil layer type to obtain the stress parameters for different soil layer types at each excavation step, include: In each excavation step, the maximum shear stress component at the Gaussian point of the soil mass is extracted for all soil layer types. Based on the maximum shear stress component, a three-dimensional shear stress field distribution map is generated by spatial interpolation. Based on the three-dimensional shear stress field distribution map, the shear stress values ​​for each soil layer type are determined; The three-dimensional shear stress field distribution map is stored in the storage module of the three-dimensional fluid-structure interaction finite element model in the form of isosurfaces and slices.

7. The calculation method for anti-surge inrush in lock foundation pits according to claim 1, characterized in that, The steps for analyzing stress parameters of different soil types at each excavation step using predetermined shear stress testing criteria, determining soil stability of the lock pit, and outputting the lock pit's resistance to sudden heave include: Based on the stress parameters of different soil layer types in each excavation step, a sensitivity analysis was conducted on the non-uniformity of stratum distribution, the non-uniformity of soil shear strength index, and the change of confined hydraulic head. Based on the sensitivity analysis results and the structural characteristics of each soil layer type, the predetermined shear stress detection criterion is selected as the modified Mohr-Coulomb criterion. Obtain structural strength parameters and structural attenuation coefficients, and input the structural strength parameters and structural attenuation coefficients into the modified Mohr-Coulomb criterion to obtain revised values ​​of soil layer parameters for different soil layer types in each excavation step; The soil stability of the lock pit is determined by combining the revised values ​​of soil parameters for different soil types in each excavation step, and the results of the lock pit's anti-surge judgment are output.

8. A calculation device for anti-surge inrush in lock pits based on finite element analysis, characterized in that, include: The model calling unit is used to call the three-dimensional fluid-structure interaction finite element model of the lock pit, wherein the three-dimensional fluid-structure interaction finite element model is used to simulate the interaction between groundwater seepage pressure and soil deformation of the target lock. The excavation step elevation acquisition unit is used to acquire elevation information of multiple excavation steps during the excavation of the lock foundation pit; The stress calculation unit is used to input the elevation information into the three-dimensional fluid-structure coupled finite element model and calculate the stress parameters of different soil layer types in each excavation step through the three-dimensional fluid-structure coupled finite element model. The soil stability analysis unit is used to analyze the stress parameters of different soil layer types in each excavation step using a predetermined shear stress detection criterion, determine the soil stability of the lock pit, and output the lock pit anti-surge judgment result.

9. An electronic device, characterized in that, It includes one or more processors and a memory, the memory being used to store one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors cause the one or more processors to implement the calculation method for anti-surge of lock foundation pit based on finite element analysis as described in any one of claims 1 to 7.

10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the calculation method for anti-surge inrush of lock foundation pit based on finite element analysis as described in any one of claims 1 to 7.

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