Simulation method and system for anchoring of surrounding rock of underground engineering based on near-field dynamics

Abstract

The present application belongs to the field of geotechnical engineering and computational mechanics, and provides a near-field dynamics-based underground engineering surrounding rock anchoring simulation method and system, which comprises: establishing a surrounding rock near-field dynamics discrete model and a rock bolt-grouting body near-field dynamics discrete model according to the geological conditions and anchoring design parameters of the surrounding rock of the underground engineering; constructing a double-neighborhood near-field dynamics constitutive relationship and a fracture criterion for the surrounding rock area and the rock bolt-grouting body area; identifying an interface area between the rock bolt-grouting body area and the surrounding rock area, defining an interface bond for three-dimensional material points across the interface, establishing an interface bond constitutive relationship and a debonding slip failure criterion; combining boundary conditions and initial conditions, using a self-adaptive dynamic relaxation time integration algorithm to solve the pre-constructed global double-neighborhood near-field dynamics control equation in parallel to obtain the three-dimensional displacement field, damage field and interface state evolution results of the surrounding rock and the rock bolt. It can realize efficient simulation of large-scale three-dimensional anchoring systems.

Description

Technical Field

[0001] This invention belongs to the fields of geotechnical engineering and computational mechanics, and particularly relates to a method and system for simulating the anchoring of surrounding rock in underground engineering based on near-field dynamics. 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] Anchoring systems consist of three parts: steel anchor bolts, grouting material, and fractured surrounding rock. These three components interact with highly nonlinear mechanical forces, including complex behaviors such as bond-slip-debonding at the grouting interface, shear failure of the surrounding rock along structural planes, and large plastic deformation of the anchor bolt itself. Anchoring system support is a core technical means to maintain the stability of surrounding rock in underground engineering projects such as tunnels and caverns. Accurately simulating the anchoring system support process is of significant engineering importance for the design and safety assessment of underground engineering support systems.

[0004] In traditional Peridynamics (PD) methods for simulating the support process of anchoring systems, it is required that all material points in the computational domain adopt the same neighborhood radius (i.e., uniform neighborhood). This makes local densification discretization ineffective: if material points are densified in key areas (such as near the anchoring interface), the neighborhood of the material points in this area will contain a large number of neighboring points, which drastically increases the computational load while providing only limited improvement in accuracy; if non-uniform discretization is forcibly adopted, the interaction between material points no longer satisfies Newton's third law due to the inconsistent neighborhood sizes of different material points, resulting in non-conservation of linear momentum and generating "ghost force" numerical errors, which severely distort the calculation results and prevent the simulation results from being applied to actual engineering. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a method and system for simulating the anchoring of surrounding rock in underground engineering based on peri-field dynamics. This method can model both the anchor bolt and the surrounding rock as three-dimensional entities and perform non-uniform discretization of material points. It describes the complex mechanical behavior of the anchoring interface through an interface bond model, introduces double-neighbor peri-field dynamics to achieve momentum conservation under non-uniform discretization, and achieves efficient simulation of large-scale three-dimensional anchoring systems based on GPU parallel computing.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: The first aspect of the present invention provides a simulation method for anchoring surrounding rock in underground engineering based on near-field dynamics.

[0007] In one or more embodiments, a method for simulating the anchoring of surrounding rock in underground engineering based on near-field dynamics is provided, comprising: Based on the geological conditions of the surrounding rock and the anchoring design parameters of the underground engineering, three-dimensional geometric models of the surrounding rock domain and the anchor-grouting body composite domain are established respectively. Then, the three-dimensional material points of each domain are non-uniformly discretized to obtain the near-field dynamic discretization model of the surrounding rock and the near-field dynamic discretization model of the anchor-grouting body, and the neighborhood radius is independently defined for each three-dimensional material point. Construct the near-field dynamic constitutive relations and fracture criteria of the two neighboring domains of the surrounding rock domain and the anchor bolt-grouting body domain; identify the interface region between the anchor bolt-grouting body domain and the surrounding rock domain, define the interface bond for the three-dimensional material point pairs across the interface, and establish the interface bond constitutive relations and debonding slip failure criteria. Based on the discrete model of peri-field dynamics of surrounding rock and the discrete model of peri-field dynamics of anchor bolt and grouting body, the constitutive relations and fracture criteria of peri-field dynamics of the surrounding rock domain and the anchor bolt and grouting body domain, as well as the constitutive relations of interface bonds and the debonding and slip failure criteria, and combined with boundary conditions and initial conditions, the pre-constructed global double-neighbor peri-field dynamic control equations are solved in parallel using an adaptive dynamic relaxation time integral algorithm, so as to obtain the three-dimensional displacement field, damage field and interface state evolution results of the surrounding rock and anchor bolt.

[0008] As one implementation method, the three-dimensional geometric model of the surrounding rock domain is: a cuboid rock block containing pre-set joint surfaces, with the joint surfaces pre-embedded in the model in the form of geometric surfaces; The three-dimensional geometric model of the anchor bolt-grouting composite domain is: a cylinder passing through the joint surface, where the inner cylinder is the anchor bolt steel and the outer annular region is the grouting body.

[0009] As one implementation method, the process of non-uniformly discretizing three-dimensional material points in each domain includes: Based on the geometric characteristics and computational accuracy requirements of the surrounding rock domain and the anchor-grouting composite domain, corresponding heterogeneous adaptive finite element meshes are generated respectively. Each domain heterogeneous adaptive finite element mesh is transformed into a corresponding near-field dynamic non-uniform discrete material point. Each near-field dynamic non-uniform discrete material point inherits the geometric center coordinates, volume, and material properties of the corresponding mesh element. The distribution of material points is densified in the neighborhood region of the anchoring interface with a preset radius. The neighborhood radius of each material point is determined independently based on the local material point spacing.

[0010] As one implementation method, the global dual-neighborhood peri-field dynamics control equations include positive integral terms from the neighborhood and corrected integral terms from the dual neighborhood. Together, they ensure the conservation of linear momentum under non-uniform discretization and eliminate ghost force numerical errors.

[0011] As one implementation method, the near-field dynamic constitutive relation and fracture criterion of the two-neighbor domain of the surrounding rock domain are as follows: the near-field dynamic constitutive relation of the two-neighbor domain adopts a bond-based elastic-brittle constitutive model, and the bonds at the joint surface are simulated by a pre-set critical elongation rate to simulate the weakening effect of the joint surface. The near-field dynamic constitutive relation and fracture criterion of the anchor bolt-grouting composite domain in the two neighboring regions are as follows: In the anchor bolt-grout composite domain, the anchor bolt steel adopts a state-based elastoplastic near-field dynamic constitutive model, the plastic yield criterion adopts the von Mises criterion, and the elastoplastic constitutive integration is performed by the radial back mapping algorithm; the grout adopts a bond-based elastoplastic constitutive model, and its micromodulus parameter is determined by the elastic modulus and fracture toughness of the grout.

[0012] As one implementation method, the criterion for identifying the interface region between the anchor bolt-grouting body domain and the surrounding rock domain is: the distance between the material points in the anchor bolt-grouting body domain and the material points in the surrounding rock domain does not exceed the interface bond search radius, which is determined by the grouting layer thickness and the spacing between the material points.

[0013] As one implementation method, the interfacial bond constitutive model describes the entire mechanical behavior of the anchoring interface from elastic bonding to damage softening and finally complete debonding, which includes: The damage initiation criterion for the interface key adopts the second nominal stress criterion; Damage evolution is described using the BK criterion based on mixed-mode fracture energy; When the interface bond damage variable reaches 1, the interface bond is completely ineffective, and only the normal compressive contact is retained to prevent material point penetration.

[0014] As one implementation method, a GPU parallel computing architecture is adopted to solve the pre-built global double neighborhood near-field dynamic control equations in parallel computing. During the parallel computing process, a spatial hash grid is used to spatially index the material points, and the three-dimensional computing domain is divided into uniform grid units. Each material point is mapped to the corresponding hash bucket according to its coordinates, so as to achieve fast retrieval of neighborhood material points with O(1) complexity. The material points in the surrounding rock domain, the material points in the anchor bolt-grouting body domain, and the interface key information are stored in the GPU memory respectively, and the GPU memory access mode is optimized by using a structure array memory layout. Each material point is assigned a GPU thread, and each thread independently calculates the bond force contribution in the neighborhood of that material point, while automatically accumulating the dual neighborhood correction contribution. The mechanical calculation of the interface bond is executed as an independent GPU kernel function, and the interface bond force is applied to the corresponding material points in the surrounding rock domain and the anchor-grouting body domain, respectively.

[0015] A second aspect of the present invention provides a simulation system for anchoring surrounding rock in underground engineering based on near-field dynamics.

[0016] In one or more embodiments, an underground engineering surrounding rock anchoring simulation system based on near-field dynamics includes: The three-dimensional material point discretization module is used to establish three-dimensional geometric models of the surrounding rock domain and the anchor-grouting body composite domain according to the geological conditions of the surrounding rock and the anchor design parameters of the underground engineering. Then, the three-dimensional material points are non-uniformly discretized in each domain to obtain the near-field dynamic discretization model of the surrounding rock and the near-field dynamic discretization model of the anchor-grouting body, and the neighborhood radius is independently defined for each three-dimensional material point. The constitutive relation construction module is used to construct the near-field dynamic constitutive relation and fracture criterion of the two neighboring domains of the surrounding rock domain and the anchor bolt-grouting body domain; identify the interface region between the anchor bolt-grouting body domain and the surrounding rock domain; define the interface bond for the three-dimensional material point pairs across the interface; and establish the interface bond constitutive relation and debonding slip failure criterion. The parallel solution module is used to solve the pre-constructed global double-neighbor near-field dynamic control equations in parallel based on the discrete models of the surrounding rock near-field dynamics and the anchor-grouting body near-field dynamics, the constitutive relations and fracture criteria of the two-neighbor near-field dynamics of the surrounding rock domain and the anchor-grouting body domain, the constitutive relations of the interface bonds and the debonding and slip failure criteria, and the boundary conditions and initial conditions.

[0017] A third aspect of the present invention provides an electronic device.

[0018] 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 above-described simulation method for anchoring surrounding rock in underground engineering based on near-field dynamics.

[0019] Compared with the prior art, the beneficial effects of the present invention are: This invention models both the surrounding rock and the anchor-grouting body as three-dimensional entities. Through heterogeneous adaptive mesh generation and material point transformation, non-uniform discrete models of the peri-field dynamics of each domain are obtained. The invention introduces the theory of dual-neighborhood peri-field dynamics, allowing different material points within the computational domain to have their own independent neighborhood radii. A dual-neighborhood correction term ensures the conservation of linear momentum under non-uniform discretization, fundamentally eliminating numerical errors caused by "ghost forces." The surrounding rock domain adopts an elastic-brittle bond constitutive model, the anchor domain adopts a state-based elastic-plastic constitutive model, and the grouting body adopts an elastic-brittle bond constitutive model. Interface bonds are defined at the anchoring interface, and a cohesive constitutive model incorporating damage initiation and evolution is used to describe the entire bonding-damage-debonding process of the interface. Based on a GPU parallel computing architecture and combined with spatial hashing grid technology, rapid neighborhood construction is achieved. An adaptive dynamic relaxation algorithm is used to efficiently solve the global equations, realizing a full three-dimensional high-precision simulation of the anchoring system, significantly improving computational efficiency and providing an effective tool for the refined analysis of anchoring effects in underground engineering. Attached Figure Description

[0020] 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.

[0021] Figure 1 This is a flowchart of the simulation method for anchoring surrounding rock in underground engineering based on near-field dynamics according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the non-uniform dispersion of three-dimensional material points in the surrounding rock domain and the anchor-grouting body composite domain according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the dual neighborhood of an embodiment of the present invention; Figure 4 This is a schematic diagram of the interface key recognition and constitutive model according to an embodiment of the present invention; Figure 5 This is a schematic diagram of the GPU parallel computing architecture and spatial hash grid according to an embodiment of the present invention; Figure 6 This is a schematic diagram of a three-dimensional shear numerical model of anchored jointed rock mass according to an embodiment of the present invention. Detailed Implementation

[0022] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0023] 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.

[0024] 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.

[0025] Figure 1 A schematic diagram of the simulation method for anchoring surrounding rock in underground engineering based on near-field dynamics, according to an embodiment of the present invention, is provided. Figure 1 The simulation method for anchoring surrounding rock in underground engineering based on near-field dynamics in this embodiment may include the following steps S1 to S3.

[0026] The specific implementation process of steps S1 to S3 is as follows: Step S1: Based on the geological conditions of the surrounding rock and the anchoring design parameters, establish three-dimensional geometric models of the surrounding rock domain and the anchor-grouting composite domain, respectively. Then, perform non-uniform discretization of the three-dimensional material points in each domain to obtain the near-field dynamic discretization model of the surrounding rock and the near-field dynamic discretization model of the anchor-grouting composite domain. Define an independent neighborhood radius for each three-dimensional material point, such as... Figure 2 As shown.

[0027] Based on the actual engineering situation, a three-dimensional geometric model of the surrounding rock zone and a three-dimensional geometric model of the anchor bolt-grouting body composite zone were established. Among them, such as... Figure 6 As shown, the three-dimensional geometric model of the surrounding rock domain is a cuboid rock block with pre-defined joint surfaces, which are pre-embedded in the model in the form of geometric surfaces. The three-dimensional geometric model of the anchor bolt-grouting composite domain is a cylinder passing through the joint surfaces, where the inner cylinder is the anchor bolt steel and the outer annular region is the grouting body.

[0028] The non-uniform discretization here is based on the triangular / tetrahedral element mesh obtained by discretization using finite element software, etc. The centroid of each triangle is defined as a material point, and the volume of the tetrahedron is defined as the volume of the material point.

[0029] In step S1, the process of non-uniform discretization of three-dimensional material points in each domain includes: Step S11: Generate heterogeneous adaptive finite element meshes for the surrounding rock domain and the anchor-grouting composite domain according to their geometric characteristics and calculation accuracy requirements.

[0030] To improve simulation accuracy in critical areas, we refine the mesh near joint surfaces, the anchor-surrounding rock interface, and stress concentration zones. We use a coarser mesh further away from critical areas to reduce overall computational cost.

[0031] Step S12: Transform the finite element mesh into near-field dynamic non-uniform discrete material points. Each material point inherits the geometric center coordinates, volume, and material properties of the corresponding mesh element.

[0032] The geometric center of each finite element is taken as the coordinates of the material point, the volume of the element is taken as the volume of the material point, and the material properties of the element are assigned to the corresponding material point. Thus, the surrounding rock domain, the grouting body domain, and the anchor domain each obtain their corresponding sets of material points, which together constitute the global material point model.

[0033] Step S13: Densify the distribution of material points in the region near the anchoring interface to improve the accuracy of interface behavior simulation; wherein, the neighborhood radius of each material point is determined independently based on the local material point spacing, thereby achieving a reasonable configuration of non-uniform neighborhoods.

[0034] Neighborhood radius of each material point Based on its local material point spacing dx Determined independently, usually taken ( (This is a constant coefficient, usually taken as 3), thus achieving a reasonable configuration of non-uniform neighborhoods with smaller neighborhood radii in encrypted regions and larger neighborhood radii in sparse regions.

[0035] This embodiment models both the anchor bolt and the surrounding rock as three-dimensional solids and discretizes them into material points, completely abandoning the traditional approach of simplifying the anchor bolt to a one-dimensional beam element. This approach accurately reflects the three-dimensional stress state within the anchor bolt cross-section, the true contact relationship between the anchor bolt and the grouting body, and the plastic behavior of the anchor bolt under large deformation, significantly improving the accuracy of the anchoring effect simulation. Within a unified near-field dynamics framework, it simultaneously describes the fracture damage of the surrounding rock and the large elastoplastic deformation of the anchor bolt, eliminating the need for coupling between different numerical methods and avoiding the accumulation of numerical errors and information loss at the coupling interface.

[0036] Traditional peridynamics requires all matter points to have the same neighborhood radius, which leads to asymmetric interactions between matter points in non-uniform discretization, non-conservation of linear momentum, and numerical errors caused by "ghost forces." Dual-Horizon Peridynamics (DH-PD) introduces the concept of dual neighborhoods, allowing each matter point to have an independent neighborhood radius while ensuring global momentum conservation.

[0037] like Figure 3 As shown, for a matter point its neighborhood Includes all with Distance not exceeding The matter point; its dual neighborhood Then it includes all of the following: For a given neighborhood member, all neighborhood radii are large enough to be "seen". The material point.

[0038] The core of dual-neighborhood peri-field dynamics lies in allowing different material points within the computational domain to have their own independent neighborhood radii, and ensuring momentum conservation in non-uniform neighborhoods by introducing the concept of dual neighborhoods.

[0039] For matter points Its neighborhood is defined as: (1) in For matter points The neighborhood radius can vary with the location of the material point, taking a smaller value in densely populated regions and a larger value in sparse regions.

[0040] Dual neighborhood is defined as all neighborhoods containing The set of matter points: (2) The definition of dual neighborhood implies: If and only if .

[0041] The governing equations for the two-neighbor peridynamics are: (3) in, For material density, For acceleration, For matter points right The density of applied bond forces, This represents the body density. The first integral term in the governing equation is calculated from the neighborhood. Internal matter point pairs The force, the second integral term is calculated from the dual neighborhood. Internal matter point pairs The reaction force; it is this dual neighborhood correction term that ensures the conservation of linear momentum in the non-uniform neighborhood, fundamentally eliminating the numerical error of "ghost force". This equation is a direct generalization of the traditional peri-field dynamics governing equation. When the neighborhood radii of all material points are the same, The above equation degenerates into the governing equation of traditional near-field dynamics.

[0042] Step S2: Construct the near-field dynamic constitutive relations and fracture criteria of the two neighboring domains of the surrounding rock domain and the anchor bolt-grouting body domain; identify the interface region between the anchor bolt-grouting body domain and the surrounding rock domain, define the interface bond for the three-dimensional material point pairs crossing the interface, and establish the interface bond constitutive relations and debonding slip failure criteria.

[0043] A key characteristic of dual-neighborhood near-field dynamics is that the contribution of the dual neighborhood requires no additional traversal overhead and is automatically accumulated when calculating the bond forces in the neighborhood of each material point. Specifically, when calculating the bond forces in the neighborhood of each material point... Matter points in its neighborhood When the bond force is applied, the opposite force is simultaneously applied. Accumulated to The combined force can automatically calculate the dual neighborhood correction term without introducing any additional computational overhead.

[0044] For group near-field dynamics (BB-PD), matter points Matter points in its neighborhood ( The applied bond force density is: (4) Matter Point right ( The applied reverse bond force density is: (5) in, and Based on matter points and The micro-elastic modulus of their respective neighborhood radii. The elongation of the bond. Let be the unit direction vector of the bond. Since the neighborhood radii of different material points are different, That is, a single bond no longer satisfies Newton's third law; however, the global momentum conservation is guaranteed by the correction of the dual neighborhood integral term.

[0045] The near-field dynamic constitutive relations of the two-neighbor domain in the surrounding rock domain are derived using a bond-based elastobrittle constitutive model. The force density function is: (6) in, The micromodulus constant of the surrounding rock is derived from the elastic modulus. and neighborhood radius Sure; Elongation of the bond; For the state function of the bond, when the bond elongation exceeds a critical value... At that time, the bond undergoes irreversible breakage. Set to 0.

[0046] Critical elongation of the bond fracture energy of surrounding rock Sure: (7) in, This is the average of the neighborhood radii of the two material points that form the bond.

[0047] The bonds at the joint surfaces are controlled by pre-setting the critical elongation. This simulates the weakening effect of joint surfaces, thus naturally achieving the mechanical description of joint surfaces within the near-field dynamics framework without introducing additional contact algorithms.

[0048] Damage variables at material points Defined as: (8) The anchor steel is modeled using a state-based elastoplastic near-field dynamic constitutive model (OSB-PD), which can describe the volumetric and shear deformation of the material and is suitable for simulating large plastic deformations of metallic materials. The von Mises criterion is used for plastic yielding, and plastic correction is achieved by performing a radial back-mapping algorithm at each material point. The grout body is modeled using a bond-based elastoplastic-brittle constitutive model, and its micromodulus parameters are determined by the elastic modulus and fracture toughness of the grout body.

[0049] Yield function Defined as: (9) in, For the deviatoric stress tensor, To adapt to equivalent plastic strain The evolving isotropic hardening yield stress was determined; an elastoplastic constitutive integral was performed at each material point using a radial back-mapping algorithm. The grout was modeled as a bond-based elastoplastic-brittle constitutive model, with its micromodulus parameters determined by the elastic modulus and fracture toughness of the grout.

[0050] This embodiment introduces dual-neighborhood near-field dynamics, which allows different material points in the computational domain to have their own independent neighborhood radii. The linear momentum conservation under non-uniform discretization is guaranteed by the dual-neighborhood correction term, which fundamentally eliminates the numerical error of "ghost force" and achieves local densification of key regions without reducing the computational accuracy.

[0051] Identify the interface region between the anchor bolt-grouting body domain and the surrounding rock domain, define interfacial bonds for three-dimensional material point pairs crossing the interface, and establish an interfacial bond constitutive model describing the bonding, damage, and debonding behavior of the anchorage interface, such as... Figure 4 As shown. The identification criterion for interface keys is: material points. Belongs to the anchor bolt-grouting body domain, material point It belongs to the surrounding rock zone, and the distance between the two satisfies ,in The search radius for the interface key is determined by the grouting layer thickness. Spacing between material points Jointly determined: (10) in, The expansion factor (usually taken as 1.0~1.5) is used to ensure that all material points in the interface region are included in the interface bond system.

[0052] The interface bond constitutive model describes the mechanical behavior of the anchoring interface from elastic bonding to damage softening and finally complete debonding; the mechanical behavior of the interface bond is described by a cohesive constitutive model that includes four stages: elasticity, damage initiation, damage evolution and complete failure.

[0053] Elastic phase: The traction force-displacement relationship of the interface bond is linear. (11) in, , , These are the interface stiffness parameters in the normal and two tangential directions, respectively, which are determined by the elastic modulus of the grout and the interface thickness.

[0054] Damage initiation: The damage initiation criterion for the interface bond adopts the second nominal stress criterion. (12) in, The normal traction force of the interface key. and There are two tangential traction forces. , and For the corresponding strength parameters, The brackets are for Macauley.

[0055] Damage evolution: It is described by the BK criterion based on the fracture energy of the mixed mode.

[0056] Damage variables Defined as: (13) in, For the equivalent displacement of the hybrid mode, This is the equivalent displacement at the onset of damage. The equivalent displacement at complete failure is determined by the BK mixed-mode fracture energy criterion: (14) in, , For normal and tangential fracture energies, This is the BK index.

[0057] Complete Failure: Damage Variables of Interface Keys The interface key becomes completely ineffective when the relative displacement monotonically increases to 1, that is, when... At this time, the interface key becomes completely ineffective and no longer transmits any traction force, only maintaining normal compression contact to prevent material point penetration.

[0058] Step S3: Based on the discrete model of the peri-field dynamics of the surrounding rock and the discrete model of the peri-field dynamics of the anchor bolt and the grouting body, the constitutive relations and fracture criteria of the peri-field dynamics of the surrounding rock domain and the anchor bolt and grouting body domain, as well as the constitutive relations of the interface bond and the debonding and slip failure criteria, and combined with the boundary conditions and initial conditions, the pre-constructed global double-neighbor peri-field dynamics control equations are solved in parallel using an adaptive dynamic relaxation time integral algorithm to obtain the three-dimensional displacement field, damage field and interface state evolution results of the surrounding rock and the anchor bolt.

[0059] Interface Key The resulting traction vector Apply as follows: to the anchor bolt-grouting body area material points. Apply force For the material points in the surrounding rock domain Apply force (Action and reaction forces). The interfacial bond force on each material point is the sum of all its associated interfacial bond forces, which is added as a volumetric force density term to the peri-field dynamics governing equations.

[0060] In the specific implementation process, a GPU parallel computing architecture is adopted to solve the pre-constructed global dual-neighborhood near-field dynamics control equations in parallel. For example... Figure 5 As shown, the implementation of the GPU parallel computing architecture includes: (a) Spatial hash grid technology is used to index material points in space. The three-dimensional computational domain is divided into uniform grid units. Each material point is mapped to the corresponding hash bucket according to its coordinates, so as to realize fast retrieval of neighborhood material points with O(1) complexity. The three-dimensional computational domain is divided into sections with side lengths of... A spatial hash table is established using uniform grid cells. Each material point is determined based on its coordinates. Mapped to hash bucket: (15) in, , , , For large prime numbers, This is the size of the hash table. During neighborhood search, it is only necessary to traverse the grid cell containing the target material point and its neighbors. A grid cell is used to achieve fast neighborhood retrieval with O(1) complexity.

[0061] (b) The material points of the surrounding rock domain, the material points of the anchor bolt-grouting body domain, and the interface key information are stored in the GPU memory respectively, and the GPU memory access mode is optimized by using the structure array (SoA) memory layout. The structure array (SoA) memory layout is adopted to store the coordinates, displacement, velocity, acceleration, physical force and other attributes of the material points as contiguous arrays, which makes full use of the GPU’s merged memory access feature and maximizes memory bandwidth utilization.

[0062] (c) Allocate a GPU thread for each material point, and each thread independently calculates the neighborhood of that material point. The bond force contribution of all material points (corresponding to the first integral term of the governing equation) is calculated, and the reverse bond force is automatically accumulated to the current material point when traversing the neighborhood of other material points (corresponding to the contribution of the dual neighborhood, i.e. the second integral term of the governing equation), without the need for additional traversal overhead. Design two types of GPU kernel functions: Intradomain bond force kernel function: Allocate one GPU thread for each material point, and each thread traverses the neighborhood of that material point. For all material points within the range, calculate the bond force contribution and accumulate it to the resultant force; at the same time, accumulate the anti-bond force to the resultant force of the neighboring material points through atomic operations, automatically realizing the accumulation of the dual neighborhood contribution without additional traversal; Interface bond force kernel function: Allocate a GPU thread for each interface bond, calculate the interface traction force and accumulate the resultant force to the material points at both ends through atomic operations.

[0063] (d) The mechanical calculation of the interface bond is executed as an independent GPU kernel function, and the interface bond force is applied to the corresponding material points in the surrounding rock domain and the anchor-grouting body domain, respectively.

[0064] The quasi-static problem is solved using the Adaptive Dynamic Relaxation (ADR) algorithm, which adaptively adjusts the damping coefficient at each time step. To accelerate convergence, it eliminates the need to assemble the global stiffness matrix, is fully compatible with the meshless nature of near-field dynamics, and is easily parallelized on a GPU. After computation, the outputs are: the three-dimensional displacement field and damage field of the surrounding rock domain. ; Three-dimensional displacement field and equivalent plastic strain distribution in the anchor bolt domain Three-dimensional displacement field and damage distribution in the grouting body domain; damage state of interfacial bonds. Spatial distribution; macroscopic load-displacement curve of the system.

[0065] This embodiment is based on a GPU parallel computing architecture and combines spatial hash grid technology to achieve rapid construction of neighborhoods, which greatly improves the computational efficiency of large-scale three-dimensional anchoring systems and makes it possible to perform fine-grained three-dimensional simulations at the engineering scale.

[0066] The underground engineering surrounding rock anchoring simulation method based on peri-field dynamics in this invention can treat both the anchor bolt and the surrounding rock as three-dimensional entities, directly adopt a unified peri-field dynamics framework for full three-dimensional high-precision simulation, allow non-uniform material points to be discretized without introducing "ghost force" numerical errors, and take into account computational efficiency.

[0067] In one or more embodiments, a simulation system for anchoring surrounding rock in underground engineering based on peridynamics is also provided, which can be implemented in software. The simulation system for anchoring surrounding rock in underground engineering based on peridynamics includes the following software modules: The three-dimensional material point discretization module is used to establish three-dimensional geometric models of the surrounding rock domain and the anchor-grouting body composite domain according to the geological conditions of the surrounding rock and the anchor design parameters of the underground engineering. Then, the three-dimensional material points are non-uniformly discretized in each domain to obtain the near-field dynamic discretization model of the surrounding rock and the near-field dynamic discretization model of the anchor-grouting body, and the neighborhood radius is independently defined for each three-dimensional material point. The constitutive relation construction module is used to construct the near-field dynamic constitutive relation and fracture criterion of the two neighboring domains of the surrounding rock domain and the anchor bolt-grouting body domain; identify the interface region between the anchor bolt-grouting body domain and the surrounding rock domain; define the interface bond for the three-dimensional material point pairs across the interface; and establish the interface bond constitutive relation and debonding slip failure criterion. The parallel solution module is used to solve the pre-constructed global double-neighbor near-field dynamic control equations in parallel based on the discrete models of the surrounding rock near-field dynamics and the anchor-grouting body near-field dynamics, the constitutive relations and fracture criteria of the two-neighbor near-field dynamics of the surrounding rock domain and the anchor-grouting body domain, the constitutive relations of the interface bonds and the debonding and slip failure criteria, and the boundary conditions and initial conditions.

[0068] It should be noted that each module in the underground engineering surrounding rock anchoring simulation system based on near-field dynamics in this embodiment corresponds one-to-one with each step in the underground engineering surrounding rock anchoring simulation method based on near-field dynamics in the above embodiment, and their specific implementation processes are the same, so they will not be repeated here.

[0069] The structure of the electronic device according to an embodiment of the present invention will be described in detail below. The electronic device provided in this embodiment includes at least one processor, a memory, a user interface, and at least one network interface. The various components in the underground engineering surrounding rock anchoring simulation system based on near-field dynamics are coupled together through a bus system. It can be understood that the bus system is used to realize the connection and communication between these components. In addition to a data bus, the bus system also includes a power bus, a control bus, and a status signal bus. The user interface may include a display, keyboard, mouse, trackball, click wheel, buttons, a touchpad, or a touch screen, etc.

[0070] It is understood that the memory can be volatile memory or non-volatile memory, or both. The memory in this embodiment of the invention 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 the framework layer, core library layer, driver layer, etc., used to implement various basic services and handle hardware-based tasks. Applications can include various applications.

[0071] In some embodiments, the underground engineering surrounding rock anchoring simulation system based on peridynamics provided in this invention can be implemented using a combination of hardware and software. For example, the underground engineering surrounding rock anchoring simulation system based on peridynamics provided in this invention can be a processor in the form of a hardware-decoded processor, programmed to execute the underground engineering surrounding rock anchoring simulation method based on peridynamics provided in this invention. For instance, the hardware-decoded 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.

[0072] As an example, a processor 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., where a general-purpose processor can be a microprocessor or any conventional processor, etc.

[0073] As an example of the hardware implementation of the underground engineering surrounding rock anchoring simulation system based on peri-field dynamics provided in this embodiment of the invention, the device provided in this embodiment of the invention can be directly executed by a processor 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 underground engineering surrounding rock anchoring simulation method based on peri-field dynamics provided in this embodiment of the invention.

[0074] The memory in this embodiment of the invention is used to store various types of data to support the operation of the underground engineering surrounding rock anchoring simulation system based on near-field dynamics, or to store data for execution. Figure 1 The program code for the method shown. Examples of this data include: any executable instructions for operation on a peridynamic-based underground engineering surrounding rock anchoring simulation system, such as executable instructions that can be included in the executable instructions to implement the peridynamic-based underground engineering surrounding rock anchoring simulation method of the embodiments of the present invention.

[0075] 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.

[0076] 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 1 One or more processes and / or boxesFigure 1 A device that provides the functions specified in one or more boxes.

[0077] 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. A simulation method for anchoring surrounding rock in underground engineering based on near-field dynamics, characterized in that, include: Based on the geological conditions of the surrounding rock and the anchoring design parameters of the underground engineering, three-dimensional geometric models of the surrounding rock domain and the anchor-grouting body composite domain are established respectively. Then, the three-dimensional material points of each domain are non-uniformly discretized to obtain the near-field dynamic discretization model of the surrounding rock and the near-field dynamic discretization model of the anchor-grouting body, and the neighborhood radius is independently defined for each three-dimensional material point. Construct the near-field dynamic constitutive relations and fracture criteria of the two neighboring domains of the surrounding rock domain and the anchor bolt-grouting body domain; identify the interface region between the anchor bolt-grouting body domain and the surrounding rock domain, define the interface bond for the three-dimensional material point pairs across the interface, and establish the interface bond constitutive relations and debonding slip failure criteria. Based on the discrete model of peri-field dynamics of surrounding rock and the discrete model of peri-field dynamics of anchor bolt and grouting body, the constitutive relations and fracture criteria of peri-field dynamics of the surrounding rock domain and the anchor bolt and grouting body domain, as well as the constitutive relations of interface bonds and the debonding and slip failure criteria, and combined with boundary conditions and initial conditions, the pre-constructed global double-neighbor peri-field dynamic control equations are solved in parallel using an adaptive dynamic relaxation time integral algorithm, so as to obtain the three-dimensional displacement field, damage field and interface state evolution results of the surrounding rock and anchor bolt.

2. The method for simulating the anchoring of surrounding rock in underground engineering based on near-field dynamics as described in claim 1, characterized in that, The three-dimensional geometric model of the surrounding rock domain is: a cuboid rock block containing pre-defined joint surfaces, with the joint surfaces pre-embedded in the model in the form of geometric surfaces; The three-dimensional geometric model of the anchor bolt-grouting composite domain is: a cylinder passing through the joint surface, where the inner cylinder is the anchor bolt steel and the outer annular region is the grouting body.

3. The method for simulating the anchoring of surrounding rock in underground engineering based on near-field dynamics as described in claim 1, characterized in that, The process of non-uniform discretization of three-dimensional material points in each domain includes: Based on the geometric characteristics and computational accuracy requirements of the surrounding rock domain and the anchor-grouting composite domain, corresponding heterogeneous adaptive finite element meshes are generated respectively. Each domain heterogeneous adaptive finite element mesh is transformed into a corresponding near-field dynamic non-uniform discrete material point. Each near-field dynamic non-uniform discrete material point inherits the geometric center coordinates, volume, and material properties of the corresponding mesh element. The distribution of material points is densified in the neighborhood region of the anchoring interface with a preset radius. The neighborhood radius of each material point is determined independently based on the local material point spacing.

4. The method for simulating the anchoring of surrounding rock in underground engineering based on near-field dynamics as described in claim 1, characterized in that, The global double-neighborhood peri-field dynamics control equations include positive integral terms from the neighborhood and corrected integral terms from the dual neighborhood. Together, they ensure the conservation of linear momentum under non-uniform discretization and eliminate ghost force numerical errors.

5. The method for simulating the anchoring of surrounding rock in underground engineering based on near-field dynamics as described in claim 1, characterized in that, The constitutive relation and fracture criterion of the two-neighbor peri-field dynamics of the surrounding rock domain are as follows: The constitutive relation of the two-neighbor peri-field dynamics of the surrounding rock domain adopts a bond-based elastic-brittle constitutive model, and the bonds at the joint surface are simulated by a pre-set critical elongation to simulate the weakening effect of the joint surface. The near-field dynamic constitutive relation and fracture criterion of the anchor bolt-grouting composite domain in the two neighboring regions are as follows: In the anchor bolt-grout composite domain, the anchor bolt steel adopts a state-based elastoplastic near-field dynamic constitutive model, the plastic yield criterion adopts the von Mises criterion, and the elastoplastic constitutive integration is performed by the radial back mapping algorithm; the grout adopts a bond-based elastoplastic constitutive model, and its micromodulus parameter is determined by the elastic modulus and fracture toughness of the grout.

6. The method for simulating the anchoring of surrounding rock in underground engineering based on near-field dynamics as described in claim 1, characterized in that, The criterion for identifying the interface region between the anchor bolt-grouting body region and the surrounding rock region is: the distance between the material points in the anchor bolt-grouting body region and the material points in the surrounding rock region does not exceed the interface bond search radius, which is determined by the grouting layer thickness and the spacing between the material points.

7. The method for simulating the anchoring of surrounding rock in underground engineering based on near-field dynamics as described in claim 1, characterized in that, The interfacial bond constitutive model describes the entire mechanical behavior of the anchorage interface from elastic bonding to damage softening and finally complete debonding, which includes: The damage initiation criterion for the interface key adopts the second nominal stress criterion; Damage evolution is described using the BK criterion based on mixed-mode fracture energy; When the interface bond damage variable reaches 1, the interface bond is completely ineffective, and only the normal compressive contact is retained to prevent material point penetration.

8. The method for simulating the anchoring of surrounding rock in underground engineering based on near-field dynamics as described in claim 1, characterized in that, The GPU parallel computing architecture is adopted to solve the pre-built global double neighborhood near field dynamics control equations in parallel computing. During the parallel computing process, the spatial hash grid is used to index the material points in space. The three-dimensional computing domain is divided into uniform grid units. Each material point is mapped to the corresponding hash bucket according to its coordinates, realizing fast retrieval of neighborhood material points with O(1) complexity. The material points in the surrounding rock domain, the material points in the anchor bolt-grouting body domain, and the interface key information are stored in the GPU memory respectively, and the GPU memory access mode is optimized by using a structure array memory layout. Each material point is assigned a GPU thread, and each thread independently calculates the bond force contribution in the neighborhood of that material point, while automatically accumulating the dual neighborhood correction contribution. The mechanical calculation of the interface bond is executed as an independent GPU kernel function, and the interface bond force is applied to the corresponding material points in the surrounding rock domain and the anchor-grouting body domain, respectively.

9. A simulation system for anchoring surrounding rock in underground engineering based on near-field dynamics, characterized in that, The underground engineering surrounding rock anchoring simulation method based on near-field dynamics as described in any one of claims 1-8 includes: The three-dimensional material point discretization module is used to establish three-dimensional geometric models of the surrounding rock domain and the anchor-grouting body composite domain according to the geological conditions of the surrounding rock and the anchor design parameters of the underground engineering. Then, the three-dimensional material points are non-uniformly discretized in each domain to obtain the near-field dynamic discretization model of the surrounding rock and the near-field dynamic discretization model of the anchor-grouting body, and the neighborhood radius is independently defined for each three-dimensional material point. The constitutive relation construction module is used to construct the near-field dynamic constitutive relation and fracture criterion of the two neighboring domains of the surrounding rock domain and the anchor bolt-grouting body domain; identify the interface region between the anchor bolt-grouting body domain and the surrounding rock domain; define the interface bond for the three-dimensional material point pairs across the interface; and establish the interface bond constitutive relation and debonding slip failure criterion. The parallel solution module is used to solve the pre-constructed global double-neighbor near-field dynamic control equations in parallel based on the discrete models of the surrounding rock near-field dynamics and the anchor-grouting body near-field dynamics, the constitutive relations and fracture criteria of the two-neighbor near-field dynamics of the surrounding rock domain and the anchor-grouting body domain, the constitutive relations of the interface bonds and the debonding and slip failure criteria, and the boundary conditions and initial conditions.

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 simulation method for anchoring surrounding rock in underground engineering based on near-field dynamics as described in any one of claims 1-8.

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