Rock damage simulation method and device

Abstract

The invention provides a rock damage simulation method and device, and relates to the technical field of rock engineering. The method comprises the following steps: applying a load to a numerical model of a rock to be measured, simulating the numerical model based on least square near-field dynamics, and judging whether the numerical model has tensile failure and / or shear failure by utilizing a maximum principal stress criterion and a Mohr-Coulomb criterion; when the numerical model is not damaged, increasing the load applied to the numerical model until any damage occurs to the numerical model; and judging whether the current total load step reaches a preset total step number or not after the damage occurs, if the current load is not kept unchanged, continuing to apply the load to the numerical model until the current total load step reaches the preset total step number. According to the method, two criteria are used for identifying different damage behaviors of the rock, tensile damage and shear damage of the rock can be accurately described, the rock damage process is more accurately simulated, and disaster prediction and prevention and control in the field of rock engineering are facilitated.

Description

Technical Field

[0001] The present invention relates to the field of rock engineering technology, and in particular to a rock destruction simulation method and device. Background Art

[0002] Rock failure is often a precursor to geological disasters such as earthquakes, rock collapses and volcanic eruptions, and plays an important role in assessing the stability and safety of rock engineering facilities, such as deep geological disposal of nuclear waste, deep geothermal mining and deep mining. Numerical simulation is an important way to study rock failure, which has the advantages of low cost and repeatability. In rock engineering, naturally existing cracks and their propagation processes are usually involved. Since the classical continuum theory uses spatial derivatives in its formulas and assumes that the material is continuous when deformed, the traditional continuum mechanics method represented by the finite element method has essential difficulties in predicting discontinuous behaviors such as material damage and fracture.

[0003] In view of the shortcomings of the classical continuum theory, the peridynamic method based on nonlocal interaction and spatial integration has been proposed. The governing equations of the peridynamic theory are defined by integral equations and are still valid at discontinuities, so they are more suitable for the failure analysis of materials and structures. In actual engineering, rocks are often subjected to compressive stresses. Under the action of compressive stress, rocks often undergo different types of failure behaviors or multiple types of mixed failure behaviors, such as tensile failure, shear failure, and mixed failure of tensile failure and shear failure. Peridynamics usually uses a single criterion such as bond elongation to describe rock failure, but it is difficult to accurately describe the different failure behaviors of rocks. Summary of the invention

[0004] The present disclosure aims to solve one of the technical problems in the related art at least to some extent.

[0005] To this end, the first embodiment of the present disclosure proposes a rock destruction simulation method, comprising the following steps: S1, meshing the three-dimensional geometric model of the rock to be tested, constructing the numerical model, and using the mesh nodes in the numerical model as peridynamic particles; S2, applying a load to the numerical model, simulating the numerical model based on least squares peridynamics, and determining whether tensile failure and / or shear failure occurs to the numerical model using a maximum principal stress criterion and a Moore-Coulomb criterion; S3, in response to the numerical model not having the tensile failure and / or the shear failure, gradually loading the numerical model with load steps, increasing the load applied to the numerical model in the next load step, returning to step S2, and performing calculation for the next load step until the numerical model has the tensile failure and / or the shear failure; S4, determining that the tensile failure and / or the shear failure occurs in the numerical model, and judging whether the current total load step reaches a preset total step number; S5, in response to the current total load step not reaching the preset total number of steps, returning to step S2 to perform calculation of the next load step until the current total load step reaches the preset total number of steps.

[0006] In some embodiments of the present disclosure, the use of the maximum principal stress criterion and the Moore-Coulomb criterion to determine whether the numerical model has tensile failure and / or shear failure includes: Calculating a stiffness matrix and a load matrix of the numerical model; Solving the overall equilibrium equation according to the stiffness matrix and the load matrix to obtain a displacement matrix of each grid node; Determine the stress matrix of each grid node according to the displacement matrix of each grid node; Solving the characteristic equation based on the stress matrix of each node to obtain the maximum principal stress and the minimum principal stress of each peridynamic bond in the numerical model; Determining whether tensile failure occurs in the numerical model according to the maximum principal stress and the maximum principal stress criterion; Whether shear failure occurs in the numerical model is determined according to the maximum principal stress, the minimum principal stress and the Mohr-Coulomb criterion.

[0007] In some embodiments of the present disclosure, judging whether tensile failure occurs in the numerical model according to the maximum principal stress and the maximum principal stress criterion includes: In response to the presence of a peridynamic bond in the numerical model having a maximum principal stress greater than a uniaxial tensile strength, determining that the numerical model has tensile failure; Alternatively, in response to the absence of a peridynamic bond in the numerical model whose maximum principal stress is greater than the uniaxial tensile strength, it is determined that the numerical model has not undergone tensile failure.

[0008] In some embodiments of the present disclosure, judging whether shear failure occurs in the numerical model according to the maximum principal stress, the minimum principal stress and the Mohr-Coulomb criterion includes: Calculating the maximum shear stress and the shear failure critical condition of each peridynamic bond according to the maximum principal stress and the minimum principal stress; In response to the presence of a peridynamic bond in the numerical model where the maximum shear stress is greater than the shear failure critical condition, determining that shear failure occurs in the numerical model; Alternatively, in response to the absence of a peridynamic bond in the numerical model whose maximum shear stress is greater than the shear failure critical condition, it is determined that the numerical model does not suffer shear failure.

[0009] In some embodiments of the present disclosure, after determining that the tensile failure and / or the shear failure occurs in the numerical model, the method further includes: determining the degree of damage of each of the peridynamic particles under each load step.

[0010] The second aspect of the present disclosure provides a rock destruction simulation device, comprising: A construction module is used to mesh the three-dimensional geometric model of the rock to be tested, construct the numerical model, and use the mesh nodes in the numerical model as peridynamic particles; A first test module is used to apply a load to the numerical model, simulate the numerical model based on least squares peridynamics, and determine whether tensile failure and / or shear failure occurs to the numerical model using a maximum principal stress criterion and a Moore-Coulomb criterion; if the tensile failure and / or shear failure does not occur to the numerical model, gradually load the numerical model with load steps, increase the load applied to the numerical model in the next load step, and perform calculations for the next load step until the tensile failure and / or shear failure occurs to the numerical model; The second test module is used to determine whether the tensile failure and / or the shear failure occurs in the numerical model, and judge whether the current total load step reaches the preset total number of steps. When the current total load step does not reach the preset total number of steps, the current load is maintained to repeatedly execute the step of applying the load to the numerical model, and the next load step is calculated until the current total load step reaches the preset total number of steps.

[0011] In some embodiments of the present disclosure, the first test module is specifically used to: Calculating a stiffness matrix and a load matrix of the numerical model; Solving the overall equilibrium equation according to the stiffness matrix and the load matrix to obtain a displacement matrix of each grid node; Determine the stress matrix of each grid node according to the displacement matrix of each grid node; Solving the characteristic equation based on the stress matrix of each node to obtain the maximum principal stress and the minimum principal stress of each peridynamic bond in the numerical model; Determining whether tensile failure occurs in the numerical model according to the maximum principal stress and the maximum principal stress criterion; Whether shear failure occurs in the numerical model is determined according to the maximum principal stress, the minimum principal stress and the Mohr-Coulomb criterion.

[0012] In some embodiments of the present disclosure, the device further comprises a determination module; wherein the determination module is used to: determine the degree of damage of each of the peridynamic particles under each load step after determining that the numerical model has undergone the tensile failure and / or the shear failure.

[0013] A third aspect of the present disclosure provides an electronic device, comprising: a processor, and a memory communicatively connected to the processor; The memory stores computer-executable instructions; The processor executes the computer-executable instructions stored in the memory to implement the method described in the first aspect.

[0014] The fourth aspect of the present disclosure provides a computer-readable storage medium, characterized in that the computer-readable storage medium stores computer execution instructions, and when the computer execution instructions are executed by a processor, they are used to implement the method described in the first aspect.

[0015] The rock destruction simulation method provided by the present disclosure uses the maximum principal stress criterion and the Moore-Coulomb criterion to identify the rock destruction behavior, accurately describe the tensile failure and shear failure of the rock, and more accurately simulate the rock destruction process. Applying the method described in this embodiment to actual engineering scenarios is beneficial to disaster prediction and prevention in the field of rock engineering. In addition, since this embodiment adopts the least squares peridynamic simulation method, it can eliminate the boundary effect error and cumbersome operations such as setting material layers generated by the traditional peridynamic method calculation, greatly simplify the load and boundary condition application process, and reduce the calculation error at the model boundary.

[0016] Additional aspects and advantages of the present disclosure will be given in part in the following description and in part will be obvious from the following description or learned through practice of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and / or additional aspects and advantages of the present disclosure will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which: Figure 1 A schematic diagram of a flow chart of a rock destruction simulation method provided by an embodiment of the present disclosure; Figure 2 A schematic diagram of a peridynamic neighborhood in a numerical model provided in an embodiment of the present disclosure; Figure 3 A schematic diagram of a Mohr-Coulomb failure criterion circle provided by an embodiment of the present disclosure; Figure 4 A schematic flow chart of another rock destruction simulation method provided by an embodiment of the present disclosure; Figure 5A schematic diagram of a rock destruction simulation device provided in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0018] Embodiments of the present disclosure are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present disclosure, and should not be construed as limiting the present disclosure.

[0019] It should be noted that conventional bond-based and state-based peridynamic theories have surface effects and require volume corrections, so the present disclosure proposes a destruction simulation method based on least squares peridynamics to accurately describe the destruction behavior of rocks while eliminating the disadvantages of boundary effects in peridynamics. The least squares peridynamics method has the same calculation framework and process as the finite element method, which is conducive to the coupling of the peridynamic method and the finite element method, thereby improving the calculation efficiency. Among them, least squares peridynamics adopts the interaction of peridynamics and the concept of least squares, and is derived in combination with Taylor series expansion. Specifically, the rock destruction simulation method and device of the embodiment of the present disclosure are described below with reference to the accompanying drawings.

[0020] Figure 1 The following is a flow chart of a rock destruction simulation method provided by an embodiment of the present disclosure. Figure 1 As shown, the rock destruction simulation method may include the following steps: Step 101, meshing the three-dimensional geometric model of the rock to be tested, constructing a numerical model, and using the mesh nodes in the numerical model as peridynamic particles.

[0021] In some embodiments of the present disclosure, local mesh refinement can be performed on the key areas of interest according to the analysis needs, and mainstream meshing software can be used to generate and finally establish a numerical model of the rock to be tested. The material parameters in the numerical model are set according to the property information of the rock to be tested, including: material density ρ , elastic modulus E , Poisson's ratio ν ,tensile strength σ t , Cohesion c and internal friction angle φ .

[0022] Step 102 , applying a load to the numerical model, simulating the numerical model based on least squares peridynamics, and using the maximum principal stress criterion and the Mohr-Coulomb criterion to determine whether the numerical model has tensile failure and / or shear failure.

[0023] It should be noted that the load may be a displacement load, a force load, etc. Accordingly, when applying the load, boundary conditions may also be imposed on the numerical model according to calculation requirements, such as displacement constraints.

[0024] In order to accurately describe the different failure behaviors in rock failure simulation, the disclosed embodiment combines the least squares peridynamics, and adopts the maximum principal stress criterion and the Mohr-Coulomb criterion to respectively identify the tensile failure and shear failure of the numerical model. In one implementation, the stiffness matrix and the load matrix of the numerical model can be calculated; according to the stiffness matrix and the load matrix, the overall equilibrium equation is solved to obtain the displacement matrix of each grid node; according to the displacement matrix of each grid node, the stress matrix of each grid node is determined; based on the stress matrix of each node, the characteristic equation is solved to obtain the maximum principal stress and the minimum principal stress of each peridynamic bond in the numerical model; according to the maximum principal stress and the maximum principal stress criterion, it is judged whether the numerical model has tensile failure; according to the maximum principal stress, the minimum principal stress and the Mohr-Coulomb criterion, it is judged whether the numerical model has shear failure.

[0025] Figure 2 A schematic diagram of a peridynamic neighborhood in a numerical model provided in an embodiment of the present disclosure. Figure 2 As shown in Figure 2, the mesh nodes in the numerical model are used as peridynamic particles. , in its neighborhood there are The displacement sets of these nodes are: (1) Among them, the subscript Represents the grid node The first Neighborhood member grid nodes , and its first member is itself , , , Represents the grid nodes Displacement in three directions.

[0026] (2) in, is the set of displacements of all mesh nodes (global displacement vector), is the mapping matrix.

[0027] Stiffness matrix of the numerical model Equal to the body stiffness matrix and the boundary surface stiffness matrix The sum is expressed as follows: (3) Body stiffness matrix As shown below: (4) The H matrix is ​​calculated as follows: (5) in, Represents a grid node With the neighborhood Neighborhood members Key state parameters for bonds between grid nodes For an unbroken bond it is equal to 1, for a broken bond it is equal to 0, the bond status can be determined by the failure criterion. It is the weight function of the key, which indicates the strength of the interaction between nodes in the neighborhood, and is generally related to the distance. The G matrix is ​​expressed as follows: (6) Among them, the D matrix is ​​the material stiffness matrix, as shown in formula (7), and the C matrix is ​​shown in formula (8).

[0028] (7) Among them, E and ν are the elastic modulus and Poisson’s ratio of the material, respectively.

[0029] (8) Among them, the subscript Representation Node With its The bonds between family members (k = 1, 2, 3) is defined as: (9) in, The definition is as follows: (10) Where k = 1, 2, 3; the matrix A and The definition is as follows: (11) in, (j=1,2,3) are the distances between nodes in the neighborhood in the x, y, and z directions respectively.

[0030] Boundary surface stiffness matrix K s As shown below: (12) Among them, the M, D, and C matrices are calculated by the above formulas. and is the weight of the Gaussian integral, calculated in the same way as the finite element method, represents the shape function, and the four-node element is as shown in formula (13), , The matrix definition is as shown in formula (14), the N matrix is ​​expressed by formula (15), and the component definition is shown in formula (16).

[0031] (13) (14) in, I is an identity matrix of size 3×3.

[0032] (15) (16) (17) Calculate the load matrix F First, external physical force b Acting load matrix F b The definition is as follows: (18) Load matrix for external surface traction F s The definition is as follows: (19) in, T is the external traction on the surface boundary.

[0033] Load matrix for the numerical model The calculation is as follows: (20) Solve the overall equilibrium equation: Solve the node displacement matrix based on the mechanical equilibrium equation. First, the mass matrix needs to be solved in the dynamics problem. L : (twenty one) in, ρ is the material density.

[0034] The equations solved for the dynamics are: (twenty two) The equation to be solved in statics is: (twenty three) Solve the equilibrium equations (22) or (23) to obtain the displacement matrix of each grid node u .

[0035] The stress matrix of each mesh node can be calculated based on the displacement matrix and physical equation of each mesh node. , the calculation formula is as follows: (twenty four) in, For the The displacement matrix of the mesh nodes.

[0036] The stress matrix of each grid node is obtained by formula (24): , solving the characteristic equation to obtain the maximum principal stress of each peridynamic bond in the numerical model and minimum principal stress . where the maximum principal stress of each peridynamic bond is and minimum principal stress The definition is as follows: (25) (26) In some embodiments of the present disclosure, in each load step, it is checked whether the stress of all bonds in the neighborhood of each node in the numerical model reaches the failure condition. If the failure condition is met, the state of the marked bond is is 0. According to the maximum principal stress and the maximum principal stress criterion, it is judged whether the numerical model has tensile failure. According to the maximum principal stress, the minimum principal stress and the Mohr-Coulomb criterion, it is judged whether the numerical model has shear failure.

[0037] The maximum principal stress criterion is implemented as follows: As long as the maximum principal stress of the bond reaches the uniaxial tensile strength , the bond will undergo tensile failure: (27) When there is a peridynamic bond with a maximum principal stress greater than the uniaxial tensile strength in the numerical model, it is determined that the numerical model has tensile failure. When there is no peridynamic bond with a maximum principal stress greater than the uniaxial tensile strength in the numerical model, it is determined that the numerical model has not tensile failure.

[0038] The specific expression of the Mohr-Coulomb criterion is: (28) in, It is cohesion. is the internal friction angle. Figure 3 A schematic diagram of a Mohr-Coulomb failure criterion circle provided in an embodiment of the present disclosure.

[0039] According to the maximum principal stress and minimum principal stress , calculate the maximum shear stress for each peridynamic bond and critical conditions for shear failure : (29) The implementation process of the Mohr-Coulomb criterion is as follows: as long as the maximum shear stress of the bond reaches the critical condition of shear failure, the bond will undergo tensile failure: (30) When there is a maximum shear stress in the numerical model Greater than the critical condition of shear failure The peridynamic key of the numerical model is to determine the shear failure. When there is no maximum shear stress in the numerical model, Greater than the critical condition of shear failure The peridynamic bond of the numerical model was determined to be free of shear failure.

[0040] Step 103, in response to the numerical model not having tensile failure and / or shear failure, gradually loading the numerical model with load steps, increasing the load applied to the numerical model in the next load step, returning to execute step 102, and performing calculation for the next load step until tensile failure and / or shear failure occurs in the numerical model.

[0041] It can be understood that under the current load step, the numerical model does not undergo tensile failure and / or shear failure (i.e., no bond breaking behavior occurs), so the load is increased on the basis of the load of the current load step. , continue to apply load to the numerical model and perform calculation for the next load step until tensile failure and / or shear failure occurs in the numerical model, and then stop increasing the load.

[0042] Step 104 , determining whether tensile failure and / or shear failure occurs in the numerical model, and judging whether the current total load step reaches a preset total step number.

[0043] Step 105, in response to the current total load step not reaching the preset total number of steps, return to step 102 to calculate the next load step until the current total load step reaches the preset total number of steps.

[0044] After tensile failure and / or shear failure occurs in the numerical model, if the current total load step does not reach the preset total number of steps, the current load is kept unchanged and the load is continued to be applied to the numerical model with the same load size, in order to observe the failure behavior of the numerical model within a certain period of time after tensile failure and / or shear failure occurs. For example, the order of tensile failure and shear failure of the rock to be tested, and the failure of the bonds between each grid node under each load step (that is, understanding the mapping relationship between the load-load step-failure type of each bond) are helpful for disaster prediction and prevention in the field of rock engineering.

[0045] In order to more comprehensively describe the destructive behavior of the numerical model after it is destroyed, in some embodiments of the present disclosure, after determining that the numerical model has tensile failure and / or shear failure, the damage degree of each peridynamic particle under each load step can be determined in the process of continuing to apply load to the numerical model with the same load size, which is helpful for understanding the destructive behavior type and damage degree during the failure process of the rock to be tested, and further benefits the disaster prediction and prevention in the field of rock engineering. i The degree of damage can be given locally as the ratio of the amount of broken bonds to the total amount of interactions in a family: (31) in, μ ( i , j ) represents the scalar factor for bond breaking, is the area of ​​a neighborhood (family), For grid nodes volume.

[0046] By implementing the disclosed embodiment, the maximum principal stress criterion and the Moore-Coulomb criterion are used to identify rock failure behavior, accurately describe the tensile failure and shear failure of rocks, and accurately simulate the mixed failure mode of tensile failure and shear failure of rocks in actual scenarios. Applying the method described in this embodiment to actual engineering scenarios is beneficial to disaster prediction and prevention in the field of rock engineering. In addition, since this embodiment adopts the least squares peridynamic simulation method, it can eliminate the boundary effect errors and cumbersome operations such as setting material layers generated by the traditional peridynamic method calculation, greatly simplify the process of applying loads and boundary conditions, and reduce the calculation errors at the model boundaries.

[0047] In order to better understand the rock destruction simulation method provided by the embodiment of the present disclosure, the following will be combined with Figure 4 Describe in detail. Figure 4 FIG. 1 is a flow chart of another rock destruction simulation method provided by an embodiment of the present disclosure. Figure 4 As shown, a numerical model of the rock to be tested is constructed (401), the current total load step n=1 is initialized (402), and a load is applied to the numerical model (403). The maximum principal stress criterion and the Mohr-Coulomb criterion are used to determine whether the numerical model has tensile failure and / or shear failure (404). If the numerical model has not undergone tensile failure and / or shear failure, a load is added based on the current load. , and the current total load step n=n+1 (405), return to the step of applying load to the numerical model (403), until the numerical model undergoes tensile failure and / or shear failure. After determining that the numerical model undergoes tensile failure and / or shear failure, determine whether the current total load step n reaches the preset total number of steps N (406). If the current total load step n does not reach the preset total number of steps N, the current total load step n=n+1 (407), and the current load size is kept unchanged, return to the step of applying load to the numerical model (403), and perform the calculation of the next load step until the current total load step n reaches the preset total number of steps N, and complete the failure simulation of the rock to be tested.

[0048] Figure 5 Schematic diagram of a rock destruction simulation device provided by an embodiment of the present disclosure. Figure 5 As shown, the rock destruction simulation device may include: a construction module 501 , a first test module 502 , and a second test module 503 .

[0049] The construction module 501 is used to mesh the three-dimensional geometric model of the rock to be tested, construct a numerical model, and use the mesh nodes in the numerical model as peridynamic particles; The first test module 502 is used to apply a load to the numerical model, simulate the numerical model using least squares peridynamics, determine whether the numerical model has tensile failure and / or shear failure using the maximum principal stress criterion and the Moore-Coulomb criterion, and when the numerical model has not undergone tensile failure and / or shear failure, gradually load the numerical model with load steps, increase the load applied to the numerical model in the next load step, repeat the steps of applying the load to the numerical model and determining whether the numerical model has undergone tensile failure and / or shear failure, and perform calculations for the next load step until tensile failure and / or shear failure occurs to the numerical model; The second test module 503 is used to determine whether the numerical model has tensile failure and / or shear failure, and to judge whether the current total load step has reached a preset total number of steps. When the current total load step has not reached the preset total number of steps, the current load is maintained to repeatedly execute the steps of applying the load to the numerical model and judging whether the numerical model has tensile failure and / or shear failure, and the calculation of the next load step is performed until the current total load step reaches the preset total number of steps.

[0050] In some embodiments of the present disclosure, the first test module 502 is specifically used to: calculate the stiffness matrix and load matrix of the numerical model; solve the overall equilibrium equation according to the stiffness matrix and the load matrix to obtain the displacement matrix of each grid node; determine the stress matrix of each grid node according to the displacement matrix of each grid node; solve the characteristic equation based on the stress matrix of each node to obtain the maximum principal stress and minimum principal stress of each peridynamic bond in the numerical model; determine whether the numerical model has tensile failure according to the maximum principal stress and the maximum principal stress criterion; determine whether the numerical model has shear failure according to the maximum principal stress, the minimum principal stress and the Mohr-Coulomb criterion.

[0051] In some embodiments of the present disclosure, Figure 5 Based on the embodiment shown, the rock failure simulation device may further include a determination module, wherein the determination module is used to determine the damage degree of each peridynamic particle under each load step after determining that the numerical model has tensile failure and / or shear failure.

[0052] Regarding the device in the above embodiment, the specific manner in which each module performs operations has been described in detail in the embodiment of the method, and will not be elaborated here.

[0053] In order to implement the above embodiments, the present disclosure also proposes an electronic device, including: a processor, and a memory communicatively connected to the processor; the memory stores computer-executable instructions; the processor executes the computer-executable instructions stored in the memory to implement the method provided by the above embodiments.

[0054] In order to implement the above embodiments, the present disclosure further proposes a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, they are used to implement the methods provided by the above embodiments.

[0055] In the description of the aforementioned embodiments, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present disclosure. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0056] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present disclosure, "plurality" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0057] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code that includes one or more executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present disclosure includes additional implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present disclosure belong.

[0058] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples (non-exhaustive list) of computer-readable media include the following: an electrical connection with one or more wires (electronic device), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways if necessary, and then stored in a computer memory.

[0059] It should be understood that the various parts of the present disclosure can be implemented in hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, multiple steps or methods can be implemented in software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0060] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

[0061] In addition, each functional unit in each embodiment of the present disclosure may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0062] The storage medium mentioned above may be a read-only memory, a disk or an optical disk, etc. Although the embodiments of the present disclosure have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations of the present disclosure. A person of ordinary skill in the art may change, modify, replace and modify the above embodiments within the scope of the present disclosure.

Claims

1. A rock destruction simulation method, characterized in that: The following steps are involved: S1, meshing the three-dimensional geometric model of the rock to be tested, constructing a numerical model, and using the mesh nodes in the numerical model as peridynamic particles; S2, applying a load to the numerical model, simulating the numerical model based on least squares peridynamics, and determining whether tensile failure and / or shear failure occurs to the numerical model using a maximum principal stress criterion and a Moore-Coulomb criterion; S3, in response to the numerical model not having the tensile failure and / or the shear failure, gradually loading the numerical model with load steps, increasing the load applied to the numerical model in the next load step, returning to step S2, and performing calculation for the next load step until the numerical model has the tensile failure and / or the shear failure; S4, determining that the tensile failure and / or the shear failure occurs in the numerical model, and judging whether the current total load step reaches a preset total step number; S5, in response to the current total load step not reaching the preset total number of steps, returning to step S2 to perform calculation of the next load step until the current total load step reaches the preset total number of steps.

2. The method according to claim 1, characterized in that: The simulating the numerical model based on least squares peridynamics and judging whether the numerical model has tensile failure and / or shear failure by using the maximum principal stress criterion and the Mohr-Coulomb criterion include: Calculating a stiffness matrix and a load matrix of the numerical model; Solving the overall equilibrium equation according to the stiffness matrix and the load matrix to obtain a displacement matrix of each grid node; Determine the stress matrix of each grid node according to the displacement matrix of each grid node; Solving the characteristic equation based on the stress matrix of each node to obtain the maximum principal stress and the minimum principal stress of each peridynamic bond in the numerical model; Determining whether tensile failure occurs in the numerical model according to the maximum principal stress and the maximum principal stress criterion; Whether shear failure occurs in the numerical model is determined according to the maximum principal stress, the minimum principal stress and the Mohr-Coulomb criterion.

3. The method according to claim 2, characterized in that The step of judging whether tensile failure occurs in the numerical model according to the maximum principal stress and the maximum principal stress criterion includes: In response to the presence of a peridynamic bond in the numerical model having a maximum principal stress greater than a uniaxial tensile strength, determining that the numerical model has tensile failure; Alternatively, in response to the absence of a peridynamic bond in the numerical model whose maximum principal stress is greater than the uniaxial tensile strength, it is determined that the numerical model has not undergone tensile failure.

4. The method according to claim 2, characterized in that: The determining whether shear failure occurs in the numerical model according to the maximum principal stress, the minimum principal stress and the Mohr-Coulomb criterion includes: Calculating the maximum shear stress and the shear failure critical condition of each peridynamic bond according to the maximum principal stress and the minimum principal stress; In response to the presence of a peridynamic bond in the numerical model where the maximum shear stress is greater than the shear failure critical condition, determining that shear failure occurs in the numerical model; Alternatively, in response to the absence of a peridynamic bond in the numerical model whose maximum shear stress is greater than the shear failure critical condition, it is determined that the numerical model does not suffer shear failure.

5. The method according to claim 1, characterized in that After determining that the tensile failure and / or the shear failure occurs in the numerical model, the method further includes: The damage level of each of the peridynamic particles at each load step is determined.

6. A rock destruction simulation device, characterized in that: include: A construction module is used to mesh the three-dimensional geometric model of the rock to be tested, construct a numerical model, and use the mesh nodes in the numerical model as peridynamic particles; A first test module is used to apply a load to the numerical model, simulate the numerical model based on least squares peridynamics, and determine whether tensile failure and / or shear failure occurs to the numerical model using a maximum principal stress criterion and a Moore-Coulomb criterion; if the tensile failure and / or shear failure does not occur to the numerical model, gradually load the numerical model with load steps, increase the load applied to the numerical model in the next load step, and perform calculations for the next load step until the tensile failure and / or shear failure occurs to the numerical model; The second test module is used to determine whether the tensile failure and / or the shear failure occurs in the numerical model, and judge whether the current total load step reaches the preset total number of steps. When the current total load step does not reach the preset total number of steps, the current load is maintained to repeatedly execute the step of applying the load to the numerical model, and the next load step is calculated until the current total load step reaches the preset total number of steps.

7. The device according to claim 6, characterized in that The first test module is specifically used for: Calculating a stiffness matrix and a load matrix of the numerical model; Solving the overall equilibrium equation according to the stiffness matrix and the load matrix to obtain a displacement matrix of each grid node; Determine the stress matrix of each grid node according to the displacement matrix of each grid node; Solving the characteristic equation based on the stress matrix of each node to obtain the maximum principal stress and the minimum principal stress of each peridynamic bond in the numerical model; Determining whether tensile failure occurs in the numerical model according to the maximum principal stress and the maximum principal stress criterion; Whether shear failure occurs in the numerical model is determined according to the maximum principal stress, the minimum principal stress and the Mohr-Coulomb criterion.

8. The device according to claim 6, characterized in that The device further includes a determination module; wherein the determination module is configured to: After determining that the tensile failure and / or the shear failure occurs in the numerical model, the damage degree of each of the peridynamic particles under each load step is determined.

9. An electronic device, characterized in that: include: A processor, and a memory communicatively connected to the processor; The memory stores computer-executable instructions; The processor executes the computer-executable instructions stored in the memory to implement the method according to any one of claims 1 to 5.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer-executable instructions, which are used to implement the method according to any one of claims 1 to 5 when executed by a processor.

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