Finite Element-Near Field Dynamics Coupled Method and System for Anchoring Effect in Underground Engineering

Abstract

This invention belongs to the fields of geotechnical engineering and computational mechanics, and provides a finite element-peripheral dynamic coupling method and system for anchoring effects in underground engineering. The finite element-peripheral dynamic coupling method for anchoring effects in underground engineering includes: establishing a numerical model of the fractured surrounding rock in underground engineering based on periphery dynamics theory; constructing a corresponding anchor finite element model; for each anchor finite element model beam node, combining the numerical model of the fractured surrounding rock in underground engineering, establishing the coupling relationship between the beam node and the surrounding periphery dynamic material points; defining an interface key for each pair of beam nodes and their coupled periphery dynamic material points, and determining the mechanical behavior of the interface key; at each computation time step, performing force transfer and solving between the numerical model of the fractured surrounding rock in underground engineering and the anchor finite element model, updating the coupling relationship between the beam nodes and their coupled periphery dynamic material points, which can accurately simulate the anchoring effect in underground engineering.

Description

Technical Field

[0001] This invention belongs to the fields of geotechnical engineering and computational mechanics, and particularly relates to a finite element-near field dynamic coupling method and system for anchoring effect in underground engineering. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] Rock bolt support is a crucial measure for maintaining the stability of surrounding rock in underground engineering projects such as tunnels and caverns. The anchoring system involves complex interactions between fractured rock mass, grouting materials, and steel anchor bolts. In jointed rock masses, anchor bolts primarily bear shear loads, and their mechanical response may include multiple stages such as large deformation plastic yielding, grout interface debonding, and rock mass slippage along structural surfaces. Accurate simulation of this process is of great significance for support design and safety assessment. Existing numerical simulation methods have certain limitations. The finite element method faces challenges in handling discontinuous deformation and fracture problems in rock masses; the discrete element method is inefficient in simulating the deformation behavior of continuous anchor bolts; and simplifying the anchor bolt into a linear elastic beam element cannot accurately describe its large plastic shear deformation. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a finite element-near-field dynamic coupling method and system for anchoring effects in underground engineering, which can accurately simulate the anchoring effects in underground engineering.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: The first aspect of the present invention provides a finite element-near field dynamic coupling method for anchoring effect in underground engineering.

[0006] In one or more embodiments, a finite element-near-field dynamic coupling method for anchoring effects in underground engineering is provided, comprising: Based on peri-field dynamics theory, a numerical model of fractured surrounding rock in underground engineering is established. The rock mass is discretized into material points, and peri-field dynamic constitutive relations and fracture criteria between material points are defined. The anchor rods placed at the crack locations are discretized into Timoshenko beam elements, which are used as beam nodes. The corresponding anchor rod finite element model is constructed, and the elastic-plastic constitutive relation of the beam section is defined. For each anchor bolt finite element model beam node, combined with the numerical model of fractured surrounding rock in underground engineering, the coupling relationship between it and the surrounding near-field dynamic material points is established. Define an interface bond for each pair of beam nodes and the near-field dynamic material points coupled to them, and determine the mechanical behavior of the interface bond. At each computation time step, the force calculated for each interface key is applied as an external force to the corresponding near-field dynamic material point. The forces of all associated interface keys of each beam node are superimposed and applied as nodal loads to the anchor finite element model. The numerical model of the fractured surrounding rock in the underground engineering and the anchor finite element model are solved, and the coupling relationship between the beam node and its coupled near-field dynamic material point is updated.

[0007] As one implementation method, the process of establishing the coupling relationship between the beam nodes and the surrounding near-field dynamic material points is as follows: Define a three-dimensional spatial search area for each beam node; All near-field dynamic material points located within the search area are identified to form the associated material point set of the beam node.

[0008] As one implementation method, the radius of the search area From the formula Confirmed, among which Where is the anchor radius. The nominal thickness of the grouting layer. This is the expansion factor.

[0009] As one implementation method, the process of defining an interface bond for each pair of beam nodes and their coupled near-field dynamic material points, and determining the mechanical behavior of the interface bond, includes: Calculate the relative displacement vector between beam nodes and associated material points; The interaction force generated by the interface bond is calculated based on the relative displacement vector and the constitutive relation of the interface bond. The constitutive relation of the interface bond is used to describe the mechanical behavior of the interface from elastic bonding to damage softening and failure.

[0010] As one implementation method, the damage initiation criterion for the interface key adopts the quadratic nominal stress criterion, the expression of which is:

[0011] in, For the normal stress of the interface bond, and There are two tangential stresses. , and For the corresponding intensity parameter, <·> represents Macauley brackets.

[0012] As one implementation method, the elastoplastic constitutive relation of the beam section is described using the J2 plasticity theory framework.

[0013] As one implementation, the elastoplastic constitutive relations of the beam section include axial, bending, and shear responses; to describe the plastic behavior, a yield function based on the resultant force of the section and a plastic flow rule are introduced.

[0014] A second aspect of the present invention provides a finite element-near field dynamic coupling system for anchoring effect in underground engineering.

[0015] In one or more embodiments, a finite element-near-field dynamic coupling system for anchoring effects in underground engineering includes: The Numerical Model Construction Module for Fractured Surrounding Rock is used to establish a numerical model of fractured surrounding rock in underground engineering based on peri-field dynamics theory. It discretizes the rock mass into material points and defines the peri-field dynamic constitutive relations and fracture criteria between the material points. The anchor bolt finite element model construction module is used to discretize the anchor bolts placed at the crack location into Timoshenko beam elements, i.e., as beam nodes, to construct the corresponding anchor bolt finite element model and define the elastoplastic constitutive relation of the beam section. The module for establishing the coupling relationship between beam nodes and material points is used to establish the coupling relationship between the beam nodes of each anchor finite element model and the surrounding near-field dynamic material points, in conjunction with the numerical model of the fractured surrounding rock in underground engineering. The interface key definition and mechanical behavior determination module is used to define an interface key for each pair of beam nodes and the near-field dynamic material points coupled to them, and to determine the mechanical behavior of the interface key. The force transmission and coupling relationship update module is used to apply the force calculated by each interface key as an external force to the corresponding near-field dynamic material point at each calculation time step. The force of all associated interface keys of each beam node is superimposed and applied as a nodal load to the anchor finite element model. The module solves the numerical model of the fractured surrounding rock of the underground engineering and the anchor finite element model and updates the coupling relationship between the beam node and the near-field dynamic material point coupled with it.

[0016] A third aspect of the present invention provides a computer-readable storage medium.

[0017] A computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps in the finite element-near-field dynamic coupling method for anchoring effects in underground engineering as described above.

[0018] A fourth aspect of the present invention provides an electronic device.

[0019] An electronic device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps in the finite element-near-field dynamic coupling method for anchoring effect in underground engineering as described above.

[0020] Compared with the prior art, the beneficial effects of the present invention are: This invention couples finite element method with peri-field dynamics to simulate the anchoring effect in underground engineering. It combines peri-field dynamics, which describes material fracture, with finite element method, which describes large deformation of continuum. Furthermore, it simulates complex interfacial mechanical behavior through an interface bond model, providing a more comprehensive numerical basis for the analysis of anchoring effects in underground engineering. Attached Figure Description

[0021] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0022] Figure 1 This is a flowchart of the finite element-near-field dynamic coupling method for anchoring effect in underground engineering according to an embodiment of the present invention; Figure 2 This is the principle of constructing a numerical model for fractured surrounding rock in underground engineering according to an embodiment of the present invention; Figure 3 This is a finite element near-field dynamic coupling framework diagram of the anchoring effect in underground engineering according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the line-body contact and interface key according to an embodiment of the present invention; Figure 5 This is a schematic diagram of the numerical model of shearing of anchored jointed rock mass according to an embodiment of the present invention; Figure 6 This is a schematic diagram of the finite element-near-field dynamic coupling system for anchoring effect in underground engineering according to an embodiment of the present invention; Figure 7 This is a schematic diagram of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0023] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0024] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0025] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0026] Perifield dynamics is a nonlocal continuum theory based on integral equations, suitable for simulating the spontaneous fracture process of materials. The finite element method is highly efficient in simulating continuum structures. Therefore, constructing a coupled numerical simulation method that integrates the advantages of both is an effective way to accurately simulate the anchoring effect.

[0027] Figure 1 A schematic diagram of the finite element-near-field dynamic coupling method for anchoring effect in underground engineering, according to an embodiment of the present invention, is provided. Figure 1 The finite element-near field dynamic coupling method for anchoring effect in underground engineering in this embodiment may include the following steps S101 to S105.

[0028] The specific implementation process of steps S101 to S105 is as follows: Step S101: Based on peri-field dynamics theory, establish a numerical model of fractured surrounding rock in underground engineering, discretize the rock mass into material points, and define the peri-field dynamic constitutive relationship and fracture criterion between the material points.

[0029] Simulate a rock mass containing fractures at a predetermined dip angle. Discretize the rock mass domain into material points, with the spacing between the material points determined based on the model size and computational accuracy. Define constitutive parameters for near-field dynamics, such as Young's modulus, Poisson's ratio, and critical elongation. Set the bottom boundary of the model as a fixed constraint, and apply a horizontal displacement load to the top boundary.

[0030] according to Figure 2 As shown, the fractured rock mass is modeled using near-field dynamics theory. The rock mass is discretized into a series of material points. Its influence area Inner Neighbor Points The interaction between the elements is described by a force vector state function. The initiation and propagation of cracks in rock mass are simulated by defining a fracture criterion for the bond.

[0031] The governing equations of the near-field dynamics are integral equations, and their direct discretization scheme employs the classical meshless method:

[0032] in, It is the material density. It is acceleration. t It is time. x and q It is a point of matter. Therefore x Centered on, with radius spherical neighborhood, Indicates the near-field dynamic state. Indicates and q Related infinitesimal volumes, b It is physical density.

[0033] Step S102: Discretize the anchor rods placed at the crack locations into Timoshenko beam elements, i.e., beam nodes, construct the corresponding anchor rod finite element model, and define the elastoplastic constitutive relation of the beam section.

[0034] Anchor bolts are placed at the crack locations. The anchor bolts are discretized into multiple Timoshenko beam elements. The elastic modulus, Poisson's ratio, yield strength, and plastic hardening parameters of the anchor bolt material are defined. A finite element model based on Timoshenko beam theory is used to model the anchor bolts. This model describes the centerline displacement and section rotation of the beam. The section constitutive relations include axial, bending, and shear responses. To describe the plastic behavior, a yield function based on the resultant force of the section and a plastic flow rule are introduced.

[0035] To scientifically describe the mechanical response of anchor bolts under complex external forces, a complete geometric nonlinear Timoshenko beam theory is adopted.

[0036] First, assume , .in, u This is axial displacement. w This represents lateral displacement. u 0(x,t) is the neutral axis ( z Axial displacement of (=0). w 0 (x,t) It is the lateral deflection of the neutral axis, often abbreviated as... w(x, t) , (x,t) It is the cross section rotation angle (independent degree of freedom). The core assumptions are: (1) plane section assumption (the cross section remains plane after deformation, but is not necessarily perpendicular to the neutral axis); (2) considering finite deformation, the nonlinear term of the Green-Lagrange strain tensor (i.e., von Kármán strain) is introduced; (3) the material is linear elastic.

[0037] For the strain-displacement relationship, in the axial direction, there is the axial Green-Lagrange strain. The displacement field Substitution Among them, membrane strain It is the axial strain of the neutral axis, which includes the strain caused by the large deflection slope ( w / x The nonlinear term caused by von Kármán In the shear direction, there is engineering shear strain. .

[0038] First, based on the linear elastic stress-strain relationship The expression for the internal forces in the anchor section is obtained. (1) Axial force (2) Bending moment (3) Shear force (A shear correction factor was introduced) (to account for uneven distribution of shear stress in the cross section).

[0039] By considering the distributed axial force p x (x,t) lateral force p z (x,t) and distributed moment m(x,t) Including inertial forces, we obtain a set of nonlinear coupled equations:

[0040] This strongly nonlinear and strongly coupled set of partial differential equations fully describes the dynamic behavior of a beam considering finite deflection, shear deformation, and rotational inertia. To achieve numerical solutions for this model and characterize the plasticity of the anchor bolts, the following steps are used to implement finite element numerical solutions: Step a1: Discretize the anchor section using a layered fiber model. Apply a one-dimensional elastoplastic constitutive model (J2 plasticity theory) to each fiber layer independently, and calculate the axial force and bending moment by integrating the resultant force of the section. Step a2: Introduce a shear-plastic coupling mechanism and describe the combined plastic behavior of axial force, bending moment and shear force through the NMQ interaction yield surface; Step a3: Use the co-rotation coordinate system method to handle large rotation problems, and separate rigid body motion and deformation through coordinate transformation; Step a4: Apply the linear complementary algorithm to solve the elastic-plastic equation, transforming the plastic condition into a complementary constraint problem, thus avoiding the traditional Newton iteration; Step a5: Use an energy conservation time integration algorithm (such as the Simo algorithm) to ensure the numerical stability of the dynamic analysis.

[0041] Step S103: For each anchor bolt finite element model beam node, combined with the numerical model of the fractured surrounding rock in underground engineering, establish its coupling relationship with the surrounding near-field dynamic material points.

[0042] The process of establishing the coupling relationship between the beam nodes and the surrounding near-field dynamic material points is as follows: Define a three-dimensional spatial search region for each beam node; that is, spatial search and association: for each beam node... Define the search radius Search for and identify neighboring PD material points to form an association set. The radius of the search area. From the formula Confirmed, among which Where is the anchor radius. The nominal thickness of the grouting layer. This is the expansion factor.

[0043] All near-field dynamic material points located within the search area are identified to form the associated material point set of the beam node.

[0044] Step S104: Define an interface bond for each pair of beam nodes and the near-field dynamic material points coupled to them, such as... Figure 4 As shown, the mechanical behavior of the interface key is determined.

[0045] The process of defining an interface bond for each pair of beam nodes and their coupled near-field dynamic material points, and determining the mechanical behavior of that interface bond, includes: Calculate the relative displacement vector between beam nodes and associated material points; for example, calculate the displacement difference between associated material points and beam nodes. The calculation considers finite rotation of beam nodes, which is achieved through coordinate transformation.

[0046] The interaction forces generated by the interface bond are calculated based on the relative displacement vector and the constitutive relation of the interface bond. The constitutive relation of the interface bond is used to describe the mechanical behavior of the interface from elastic bonding to damage softening and eventual failure. Based on the material properties of the grout, the constitutive parameters of the interface bond are determined, including but not limited to stiffness parameters, strength parameters, and softening law parameters.

[0047] Specifically, an interface bond is defined for each pair of beam nodes and associated material points. The mechanical behavior of this interface bond is described using a mechanical model that includes elastic, damage, and failure stages. This model calculates the interfacial forces based on relative displacements and tracks the evolution of the interface state through damage variables.

[0048] The forces generated by the interface bonds are applied in reverse to the corresponding PD (peripheral dynamics) material points. At the same time, all interface bond forces acting on the same beam node are summed and applied as concentrated nodal forces and moments to the anchor finite element model.

[0049] The damage initiation criterion for the interface key adopts the quadratic nominal stress criterion, the expression of which is:

[0050] in, For the normal stress of the interface bond, and There are two tangential stresses. , and For the corresponding intensity parameter, <·> represents Macauley brackets.

[0051] Step S105: At each computation time step, the force calculated for each interface key is applied as an external force to the corresponding near-field dynamic material point. The forces of all associated interface keys of each beam node are superimposed and applied as nodal loads to the anchor finite element model. The numerical model of the fractured surrounding rock in the underground engineering and the anchor finite element model are solved, and the coupling relationship between the beam nodes and their coupled near-field dynamic material points is updated. Figure 5 As shown.

[0052] according to Figure 3 The solution is obtained using a time integration method. Within each time step, state updates, coupled calculations (spatial search, relative displacement calculation, constitutive invocation, force mapping), and system equation solving are performed sequentially. After calculation, multiple results are output, including the rock mass displacement field, damage field, anchor bolt internal force and plastic strain distribution, interface damage state, and the system's macroscopic load-displacement curves. These results are used to analyze the overall mechanical behavior and failure mechanism of the anchoring system.

[0053] This embodiment employs a finite element-near-field dynamics coupled method to construct a numerical simulation framework for analyzing the interaction between fractured surrounding rock and anchor support systems in underground engineering. This framework uses near-field dynamics to discretize and model the fractured rock mass using material points; and uses a finite element model based on Timoshenko beam theory to model the anchor bolts. A line-volume contact algorithm and an interface bond model are used to achieve mechanical coupling between the beam nodes and the surrounding near-field dynamic material points. The interface bond model is used to simulate the bonding, slippage, and debonding behavior of the grout. This coupled simulation method can simulate the elastic constraint, local plastic yielding, and progressive interface failure of the anchor bolts under the shear deformation of the surrounding rock.

[0054] like Figure 6 As shown, the finite element-near-field dynamic coupling system for anchoring effect in underground engineering provided by this embodiment of the invention can be implemented in software. The finite element-near-field dynamic coupling system for anchoring effect in underground engineering includes the following software modules: The numerical model construction module 601 for fractured surrounding rock is used to establish a numerical model of fractured surrounding rock in underground engineering based on peri-field dynamics theory, discretize the rock mass into material points, and define the peri-field dynamic constitutive relationship and fracture criterion between material points. The anchor bolt finite element model construction module 602 is used to discretize the anchor bolts placed at the crack location into Timoshenko beam elements, i.e., as beam nodes, to construct the corresponding anchor bolt finite element model and define the elastoplastic constitutive relation of the beam section. The beam node and material point coupling relationship establishment module 603 is used to establish the coupling relationship between the beam node and the surrounding near-field dynamic material points for each anchor finite element model, combined with the numerical model of the fractured surrounding rock of the underground engineering. Interface key definition and mechanical behavior determination module 604 is used to define an interface key for each pair of beam nodes and the near-field dynamic material points coupled to them, and to determine the mechanical behavior of the interface key. The force transmission and coupling relationship update module 605 is used to apply the force calculated by each interface key as an external force to the corresponding near-field dynamic material point at each calculation time step. The force of all associated interface keys of each beam node is superimposed and applied as a nodal load to the anchor finite element model. The numerical model of the fractured surrounding rock of the underground engineering and the anchor finite element model are solved, and the coupling relationship between the beam node and the near-field dynamic material point coupled with it is updated.

[0055] It should be noted that each module in the underground engineering anchoring effect finite element-near field dynamic coupling system of the present invention corresponds one-to-one with each step in the underground engineering anchoring effect finite element-near field dynamic coupling method in the above embodiments, and their specific implementation processes are the same, so they will not be repeated here.

[0056] The structure of the electronic device according to an embodiment of the present invention will be described in detail below. Figure 7 This is a schematic diagram of the composition structure of an electronic device provided in an embodiment of the present invention. It can be understood that... Figure 7 The diagram shows only an exemplary structure of the electronic device, not the entire structure. Some or all of the structures shown may be implemented as needed.

[0057] The electronic device provided in this embodiment of the invention includes: at least one processor 701, a memory 702, a user interface 703, and at least one network interface 704. The various components in the underground engineering anchoring effect finite element-peripheral dynamic coupling system are coupled together via a bus system 705. It can be understood that the bus system 705 is used to realize the connection and communication between these components. In addition to a data bus, the bus system 705 also includes a power bus, a control bus, and a status signal bus. However, for clarity, in... Figure 7 The general labeled all buses as Bus System 705.

[0058] The user interface 703 may include a monitor, keyboard, mouse, trackball, click wheel, buttons, touchpad, or touch screen.

[0059] It is understood that memory 702 can be volatile memory or non-volatile memory, or both. In this embodiment of the invention, memory 702 is capable of storing data to support the operation of the terminal. Examples of this data include any computer programs used to operate on the terminal, such as operating systems and applications. The operating system includes various system programs, such as framework layers, core library layers, driver layers, etc., used to implement various basic services and handle hardware-based tasks. Applications can include various applications.

[0060] In some embodiments, the underground engineering anchoring effect finite element-near-field dynamic coupling system provided by the present invention can be implemented using a combination of hardware and software. As an example, the underground engineering anchoring effect finite element-near-field dynamic coupling system provided by the present invention can be a processor in the form of a hardware decoding processor, which is programmed to execute the underground engineering anchoring effect finite element-near-field dynamic coupling method provided by the present invention. For example, the processor in the form of a hardware decoding processor can employ one or more application-specific integrated circuits (ASICs), DSPs, programmable logic devices (PLDs), complex programmable logic devices (CPLDs), field-programmable gate arrays (FPGAs), or other electronic components.

[0061] As an example, processor 701 can be an integrated circuit chip with signal processing capabilities, such as a general-purpose processor, a digital signal processor (DSP), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc., wherein the general-purpose processor can be a microprocessor or any conventional processor, etc.

[0062] As an example of the hardware implementation of the finite element-near field dynamic coupling system for anchoring effect in underground engineering provided in this embodiment of the invention, the device provided in this embodiment of the invention can be directly executed by a processor 701 in the form of a hardware decoding processor. For example, it can be executed by one or more application-specific integrated circuits (ASICs), DSPs, programmable logic devices (PLDs), complex programmable logic devices (CPLDs), field-programmable gate arrays (FPGAs), or other electronic components to implement the finite element-near field dynamic coupling method for anchoring effect in underground engineering provided in this embodiment of the invention.

[0063] The memory 702 in this embodiment of the invention is used to store various types of data to support the operation of the finite element-peripheral dynamic coupling system for anchoring effects in underground engineering, or to store data for execution. Figure 1 The program code for the method shown. Examples of this data include: any executable instructions for operating on an underground engineering anchoring effect finite element-peripheral dynamic coupling system, such as executable instructions that can be included in the executable instructions to implement the underground engineering anchoring effect finite element-peripheral dynamic coupling method of the present invention.

[0064] Specifically, according to embodiments of this application, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of this application include a computer program product comprising a computer program carried on a computer-readable medium, the computer program including functions for executing... Figure 1 The program code for the method shown. In such an embodiment, the computer program can be downloaded and installed from a network via a communication component, and / or installed from a removable medium. When the computer program is executed by the central processing unit, it performs the various functions defined in the apparatus of this application.

[0065] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, as well as combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart. Figure 1One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0066] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An underground engineering anchoring effect finite element-near field dynamics coupling method, characterized in that, include: Based on peri-field dynamics theory, a numerical model of fractured surrounding rock in underground engineering is established. The rock mass is discretized into material points, and peri-field dynamic constitutive relations and fracture criteria between material points are defined. The anchor rods placed at the crack locations are discretized into Timoshenko beam elements, which are used as beam nodes. The corresponding anchor rod finite element model is constructed, and the elastic-plastic constitutive relation of the beam section is defined. For each anchor bolt finite element model beam node, combined with the numerical model of fractured surrounding rock in underground engineering, the coupling relationship between it and the surrounding near-field dynamic material points is established. Define an interface bond for each pair of beam nodes and the near-field dynamic material points coupled to them, and determine the mechanical behavior of the interface bond. At each computation time step, the force calculated for each interface key is applied as an external force to the corresponding near-field dynamic material point. The forces of all associated interface keys of each beam node are superimposed and applied as nodal loads to the anchor finite element model. The numerical model of the fractured surrounding rock in the underground engineering and the anchor finite element model are solved, and the coupling relationship between the beam node and its coupled near-field dynamic material point is updated.

2. The underground engineering anchoring effect finite element-near field dynamics coupling method of claim 1, wherein, The process of establishing the coupling relationship between beam nodes and surrounding near-field dynamic material points is as follows: Define a three-dimensional spatial search area for each beam node; All near-field dynamic material points located within the search area are identified to form the associated material point set of the beam node.

3. The finite element-near-field dynamic coupling method for anchoring effect in underground engineering as described in claim 2, characterized in that, Radius of the search area From the formula Confirmed, among which Where is the anchor radius. The nominal thickness of the grouting layer. This is the expansion factor.

4. The finite element-near-field dynamic coupling method for anchoring effect in underground engineering as described in claim 1, characterized in that, The process of defining an interface bond for each pair of beam nodes and their coupled near-field dynamic material points, and determining the mechanical behavior of that interface bond, includes: Calculate the relative displacement vector between beam nodes and associated material points; The interaction force generated by the interface bond is calculated based on the relative displacement vector and the constitutive relation of the interface bond. The constitutive relation of the interface bond is used to describe the mechanical behavior of the interface from elastic bonding to damage softening and failure.

5. The finite element-near-field dynamic coupling method for anchoring effect in underground engineering as described in claim 4, characterized in that, The damage initiation criterion for the interface key adopts the second nominal stress criterion, the expression of which is: in, For the normal stress of the interface bond, and There are two tangential stresses. , and For the corresponding intensity parameter, <·> represents Macauley brackets.

6. The finite element-near-field dynamic coupling method for anchoring effect in underground engineering as described in claim 1, characterized in that, The elastoplastic constitutive relations of the beam section are described using the J2 plasticity theory framework.

7. The finite element-near-field dynamic coupling method for anchoring effect in underground engineering as described in claim 1, characterized in that, The elastoplastic constitutive relations of beam sections include axial, bending, and shear responses; to describe plastic behavior, a yield function based on the resultant force of the section and a plastic flow rule are introduced.

8. A finite element-near-field dynamic coupling system for anchoring effect in underground engineering, characterized in that, The finite element-near-field dynamic coupling method for anchoring effect in underground engineering, as described in any one of claims 1-7, includes: The Numerical Model Construction Module for Fractured Surrounding Rock is used to establish a numerical model of fractured surrounding rock in underground engineering based on peri-field dynamics theory. It discretizes the rock mass into material points and defines the peri-field dynamic constitutive relations and fracture criteria between the material points. The anchor bolt finite element model construction module is used to discretize the anchor bolts placed at the crack location into Timoshenko beam elements, i.e., as beam nodes, to construct the corresponding anchor bolt finite element model and define the elastoplastic constitutive relation of the beam section. The module for establishing the coupling relationship between beam nodes and material points is used to establish the coupling relationship between the beam nodes of each anchor finite element model and the surrounding near-field dynamic material points, in conjunction with the numerical model of the fractured surrounding rock in underground engineering. The interface key definition and mechanical behavior determination module is used to define an interface key for each pair of beam nodes and the near-field dynamic material points coupled to them, and to determine the mechanical behavior of the interface key. The force transmission and coupling relationship update module is used to apply the force calculated by each interface key as an external force to the corresponding near-field dynamic material point at each calculation time step. The force of all associated interface keys of each beam node is superimposed and applied as a nodal load to the anchor finite element model. The module solves the numerical model of the fractured surrounding rock of the underground engineering and the anchor finite element model and updates the coupling relationship between the beam node and the near-field dynamic material point coupled with it.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the steps in the finite element-near field dynamic coupling method for anchoring effect in underground engineering as described in any one of claims 1-7.

10. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the steps in the finite element-near field dynamic coupling method for anchoring effect in underground engineering as described in any one of claims 1-7.

Images