Rock loading and unloading response simulation method and related device

Abstract

The invention belongs to a rock test simulation method, and aims to solve the technical problems of insufficient model adaptability, lack of cyclic loading and unloading simulation and difficulty in parameter calibration due to dependence on a continuous medium mechanical model method when mechanical behaviors of rocks under cyclic loading and unloading conditions are simulated at present. According to the rock loading and unloading response simulation method and the related device, a compression hardening loading and unloading model is constructed, and the compression hardening loading and unloading model comprises a loading particle deformation constitutive model, an unloading particle deformation constitutive model, a tensile deformation constitutive model and a shear deformation constitutive model. A loading particle deformation constitutive model and an unloading particle deformation constitutive model are added in the compression hardening loading and unloading model, the rock compression hardening cyclic loading and unloading model is suitable for rock compression hardening cyclic loading and unloading simulation, and the hardening characteristic and the softening characteristic of the rock under the cyclic loading and unloading condition can be accurately reflected by finely depicting the interaction of particles in the rock to be tested.

Description

Technical Field

[0001] The present application relates to a rock testing simulation method, and specifically to a rock loading and unloading response simulation method and related devices. Background Art

[0002] The deformation, hardening and failure mechanism of rocks under external pressure is one of the core contents of rock mechanics research. In recent years, with the rapid development of computer technology and numerical simulation methods, the use of numerical models to simulate the mechanical behavior of rocks has become an important research method.

[0003] At present, the simulation of the mechanical behavior of rocks under cyclic loading and unloading conditions mostly relies on continuum mechanics models, which have great limitations in describing the hardening and softening characteristics of rocks. This is mainly reflected in the following three aspects: (1) Insufficient model adaptability: Existing continuum mechanics models are often unable to accurately reflect the true mechanical behavior of rocks under cyclic loading and unloading conditions when describing the hardening and softening characteristics of rocks. There are large errors in simulating the plastic deformation, damage accumulation and failure process of rocks.

[0004] (2) Lack of cyclic loading and unloading simulation: Although the discrete element method used in the field of rock mechanics simulation has certain advantages in simulating rock failure, there are no mature models and methods to achieve the simulation of cyclic loading and unloading of rocks. This also limits the application scope of the discrete element method in the field of rock mechanics, especially in studying the mechanical behavior of rocks under complex stress conditions.

[0005] (3) Difficulty in parameter calibration: Parameter calibration in the discrete element method is a complex and time-consuming process. Currently, there is still a lack of a systematic method to accurately calibrate the parameters in the discrete element model, which makes it difficult to ensure the reliability and accuracy of the simulation results. Summary of the invention

[0006] The present application provides a rock loading and unloading response simulation method and related devices to address the technical problems of the current method of simulating the mechanical behavior of rock under cyclic loading and unloading conditions, which relies on a continuous medium mechanics model, lacks model adaptability, lacks cyclic loading and unloading simulation, and is difficult to calibrate parameters.

[0007] In order to achieve the above objectives, this application adopts the following technical solutions: In the first aspect, the present application proposes a rock loading and unloading response simulation method, comprising: According to the rock parameters to be measured, the corresponding discrete element particle model is established; Constructing a compression hardening loading and unloading model; the compression hardening loading and unloading model includes a loading particle deformation constitutive model, an unloading particle deformation constitutive model, a tensile deformation constitutive model and a shear deformation constitutive model; Based on the discrete element particle model and the compression hardening loading and unloading model, the loading and unloading response simulation of the rock to be tested is performed multiple times to obtain the corresponding simulation results, and the rock to be tested is actually measured after each loading and unloading response simulation. According to the difference between the simulation results and the actual measurement results, the variable parameters of the compression hardening loading and unloading model are optimized until the difference between the simulation results and the actual measurement results meets the preset requirement range, thereby obtaining the optimized compression hardening loading and unloading model; Based on the discrete element particle model and the optimized compression hardening loading and unloading model, the loading and unloading response simulation of the rock parameters to be tested is carried out.

[0008] Furthermore, the loaded particle deformation constitutive model includes:

[0009] in, represents the particle contact force, represents the particle closure amount, represents the initial compressive stiffness, Indicates the maximum allowable closure amount of the particle.

[0010] Furthermore, the unloading particle deformation constitutive model includes:

[0011] in, represents a dimensionless parameter, represents the dimensionless parameter of stress, The closing quantity representing the transition state from loading to unloading; and Both are greater than zero.

[0012] Furthermore, the tensile deformation constitutive model comprises:

[0013] in, represents the tensile stress of the particle contact, represents the tensile displacement of the particle contact, represents the tensile stiffness of the particle contact, represents the tensile strength of particle contact, Indicates tensile fracture.

[0014] Furthermore, the shear deformation constitutive model comprises:

[0015] in, represents the shear stress of the particle contact, represents the shear stiffness of the particle contact, represents the shear displacement of the particle contact, represents the compressive stress of the particle contact, represents the friction angle of particle contact, Indicates shear fracture, Represents the cohesion of particle contact.

[0016] Furthermore, the variable parameters of the optimized compression hardening loading and unloading model include: initial compression stiffness , Maximum allowable closure amount of particles , dimensionless parameters , stress parameters of the same dimension , the tensile stiffness of the particle contact , shear stiffness of particle contact , tensile strength of particle contact , the friction angle of particle contact Cohesion of contact with particles .

[0017] Furthermore, the discrete element particle model is based on PFC2D software and is implemented through secondary development using C++ language programming; The compression hardening loading and unloading model generates a dynamic link library file by compiling, and when the compression hardening loading and unloading model is used, it is called through the PFC2D software.

[0018] In the second aspect, the present application proposes a rock loading and unloading response simulation system, comprising: The first model building module is used to build a corresponding discrete element particle model according to the rock parameters to be measured; The second model building module is used to build a compression hardening loading and unloading model; the compression hardening loading and unloading model includes a loading particle deformation constitutive model, an unloading particle deformation constitutive model, a tensile deformation constitutive model and a shear deformation constitutive model; The parameter optimization module is used to simulate the loading and unloading response of the rock to be tested multiple times based on the discrete element particle model and the compression hardening loading and unloading model to obtain the corresponding simulation results, and to actually measure the rock to be tested after each loading and unloading response simulation, and to optimize the variable parameters of the compression hardening loading and unloading model according to the difference between the simulation results and the actual measurement results, until the difference between the simulation results and the actual measurement results meets the preset requirement range, thereby obtaining the optimized compression hardening loading and unloading model; The simulation module is used to simulate the loading and unloading response of the rock parameters to be tested based on the discrete element particle model and the optimized compression hardening loading and unloading model.

[0019] In the third aspect, the present application proposes an electronic device, comprising: a memory, and one or more processors; the memory is coupled to the processor; wherein computer program code is stored in the memory, and the computer program code includes computer instructions, and when the computer instructions are executed by the processor, the electronic device performs the steps of the above-mentioned rock loading and unloading response simulation method.

[0020] In a fourth aspect, the present application proposes a computer-readable storage medium, in which a computer program is stored. When the computer program is executed by a processor, the steps of the above-mentioned rock loading and unloading response simulation method are implemented.

[0021] Compared with the prior art, this application has the following beneficial effects: The present application proposes a method for simulating the response of rock loading and unloading, and constructs a compression hardening loading and unloading model. The compression hardening loading and unloading model includes a loading particle deformation constitutive model, an unloading particle deformation constitutive model, a tensile deformation constitutive model, and a shear deformation constitutive model. Compared with the prior art, the compression hardening loading and unloading model adds a loading particle deformation constitutive model and an unloading particle deformation constitutive model, which is suitable for the simulation of rock compression hardening cyclic loading and unloading. By finely depicting the interaction between the internal particles of the rock to be tested, it can accurately reflect the hardening and softening characteristics of the rock under cyclic loading and unloading conditions. The compression hardening loading and unloading model can simulate the deformation, hardening and damage accumulation process of the rock during multiple loading and unloading processes, and can more accurately evaluate the durability and stability of the rock under complex stress conditions, providing a scientific basis for the safe design and construction of underground engineering. The present application helps to simulate the mechanical behavior of rock under complex stress conditions more realistically, and provide more reliable prediction and evaluation for geological engineering and geotechnical engineering. The accurate simulation of the rock compression hardening cyclic loading and unloading process is achieved, which significantly improves the accuracy and efficiency of the simulation, and also makes the present application have broad application prospects and important scientific value in the fields of geological engineering and geotechnical engineering.

[0022] The present application also proposes a rock loading and unloading response simulation system, electronic equipment and computer storage medium, which possess all the advantages of the above-mentioned rock loading and unloading response simulation method. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0024] Figure 1It is a schematic diagram of the change of stress with strain of rock specimens under single cycle loading and unloading compression; Figure 2 It is a schematic diagram of the change of stress with strain of rock samples under multiple cycles of loading and unloading compression; Figure 3 This is a schematic diagram of the variation of stress with strain when simulating cyclic loading and unloading of rock using the traditional linear model in discrete element software; Figure 4 A schematic diagram of a flow chart of a rock loading and unloading response simulation method of this application; Figure 5 Schematic diagram of the deformation constitutive model of loaded particles represented by the stress-displacement curve during the first loading process; Figure 6 Schematic diagram of the constitutive model of unloading particle deformation represented by stress-displacement curve during unloading; Figure 7 Schematic diagram of the particle deformation constitutive model represented by the stress-displacement curve during cyclic loading and unloading; Figure 8 Schematic diagram of stress-strain curve results of rock sample loading-unloading-reloading failure simulation; Fig. 9 This is a schematic diagram of the stress-strain curve results of multiple cycles of loading and unloading simulation in the embodiment of the present application; Fig.10 This is a schematic diagram of the rock loading and unloading response simulation system of this application. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0027] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0028] In the description of the embodiments of the present application, it should be noted that if the terms "upper", "lower", "horizontal", "inner", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the invented product is usually placed when used. It is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0029] In addition, if the term "horizontal" appears, it does not mean that the component must be absolutely horizontal, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", which does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0030] In the description of the embodiments of the present application, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0031] In the field of geological engineering and geotechnical engineering, the study of the mechanical properties of rocks plays a vital role in understanding crustal movement and lithosphere evolution, guiding underground engineering construction and mineral resource development. At present, in the field of rock mechanics simulation, the discrete element method is a numerical method that can take into account the complex interactions between particles and is widely used in rock failure simulation and deformation simulation. The discrete element software corresponding to the discrete element method can more realistically reflect the mechanical response of rocks in the stress process by simulating the movement and interaction of particles inside the rock. However, although the discrete element method has made certain progress in simulating rock failure, there are still great challenges in simulating rock compression hardening and cyclic loading and unloading processes.

[0032] For the simulation of the mechanical behavior of rock under cyclic loading and unloading conditions, the existing technologies mostly rely on the continuum mechanics model, which has great limitations in describing the hardening and softening characteristics of rock. Through experimental research, it can be found that the loading path and unloading path of rock are different during the cyclic loading and unloading process. Figure 1 The figure shows the change of stress with strain of rock samples under single cycle loading and unloading compression. Figure 1 As can be seen from the figure, the loading path and the unloading path are different. Figure 2 As shown in the figure, it is a schematic diagram of the change of stress with strain of rock samples under multiple cycles of loading and unloading compression. Figure 2 It can be seen that when the compressive stress is low, the particle contact has an initial compressive stiffness and produces linear deformation. When the compressive stress gradually increases, the compressive stiffness also increases, and the closure of the particle contact becomes more and more difficult. Although the current simulation based on the discrete element method can capture the interaction between rock particles, there is no mature model and method for simulating the cyclic loading and unloading of rocks. Figure 3 The figure shows the variation of stress with strain when simulating the cyclic loading and unloading of rock using the traditional linear model in discrete element software. Figure 3 It can be seen that the loading and unloading paths simulated by the traditional linear model are the same, which has a large error compared with the actual situation. Therefore, it can only simulate the linear process and cannot reproduce the experimental results. The reason is that the existing discrete element method lacks a constitutive model that characterizes the cyclic loading and unloading of rocks.

[0033] Based on the above situation, the present application proposes a rock loading and unloading response simulation method and related devices, which are described in detail below in conjunction with embodiments and drawings.

[0034] like Figure 4 As shown, a schematic diagram of a process of the rock loading and unloading response simulation method of the present application may include: S101, establishing a corresponding discrete element particle model according to the rock parameters to be measured.

[0035] In practical applications, the parameters of the rock to be tested can include physical and mechanical parameters, such as particle size distribution, density, elastic modulus, Poisson's ratio, compressive strength, tensile strength, shear strength, etc. According to the characteristics of the rock to be tested and the simulation requirements, appropriate discrete element method software can be selected, such as PFC (Particle Flow Code) or other software that can simulate the interaction between particles.

[0036] It should be noted that the Discrete Element Particle Model (DEPM) is a numerical model based on the Discrete Element Method (DEM) to simulate and analyze the behavior of granular materials. It regards particles as discrete rigid or flexible units that can collide and slide with each other, and predicts the behavior of the entire system by calculating the interaction forces between particles. In DEM, DEPM simplifies actual granular materials into a series of discrete particle units, each of which has certain physical properties (such as mass, shape, size, density, etc.) and mechanical behaviors (such as elasticity, plasticity, damping, friction, etc.).

[0037] S102, constructing a compression hardening loading and unloading model; the compression hardening loading and unloading model includes a loading particle deformation constitutive model, an unloading particle deformation constitutive model, a tensile deformation constitutive model and a shear deformation constitutive model.

[0038] It should be noted that the loaded particle deformation constitutive model is used to describe the deformation behavior of particles when they are first compressed, the unloaded particle deformation constitutive model is used to describe the recovery behavior of particles after unloading pressure, the tensile deformation constitutive model is used to describe the deformation behavior of particles when they are tensile, and the shear deformation constitutive model is used to describe the deformation behavior of particles under shear force. The constitutive model is also called the mechanical constitutive equation of the material or the stress-strain model of the material, which is a mathematical expression that describes the mechanical properties of the material.

[0039] S103, based on the discrete element particle model and the compression hardening loading and unloading model, the loading and unloading response simulation is performed on the rock to be tested for multiple times to obtain corresponding simulation results, and the rock to be tested is actually measured after each loading and unloading response simulation, and the variable parameters of the compression hardening loading and unloading model are optimized according to the difference between the simulation results and the actual measurement results, until the difference between the simulation results and the actual measurement results meets the preset requirement range, thereby obtaining the optimized compression hardening loading and unloading model.

[0040] After multiple iterations of optimization in step S103, an optimized compression hardening loading and unloading model can be obtained that can accurately reflect the loading and unloading response of the rock to be tested, which is more in line with the actual situation.

[0041] S104, simulating the loading and unloading response of the rock parameters to be tested based on the discrete element particle model and the optimized compression hardening loading and unloading model.

[0042] After the final loading and unloading response simulation of the rock to be tested is performed using the optimized compression hardening loading and unloading model and discrete element particle model, the simulation results can be analyzed in detail, including the deformation behavior, stress distribution, and failure mode of the rock. In practical applications, the mechanical properties and loading and unloading response laws of the rock to be tested can be further understood based on the simulation results.

[0043] This application achieves accurate simulation of the mechanical behavior of the rock under cyclic loading and unloading conditions by constructing a discrete element particle model and a compression hardening loading and unloading model, and has higher simulation accuracy and wider applicability.

[0044] The present application is further described as follows through a specific example: 1. Construct discrete element particle model and compression hardening loading and unloading model.

[0045] In this embodiment, the discrete element particle model is developed by using Visual C++ through the external interface of PFC2D6.0. The various constitutive models that constitute the compression hardening loading and unloading model are compiled to generate dynamic link library files (DLL) that can be loaded into the numerical calculation program when needed. In practical applications, the particle closure amount can be calculated at a given strain increment (hereinafter referred to as particle closure amount). ) returns the new stress (particle contact force later) ). When the DLL is called in PFC2D6.0, it can be loaded through the FISH (Friendly Interactive Shell, a user-friendly command-line shell) language command, and the parameters used are consistent with the names defined in the DLL source file.

[0046] The compression hardening loading and unloading model simulates the interaction between particles in the rock by defining the contact constitutive relationship between particles, and adds the compression hardening cyclic loading and unloading contact constitutive relationship and the failure strength criterion. The specific constitutive relationship under particle contact is as follows: (1) Loading particle deformation constitutive model (compression deformation during the first loading process).

[0047] The first loading process is described by the Bandis-Barton (BB) model. The BB model is a hardening model that can simulate the nonlinear compression deformation of the macroscopic rock mass structure surface. There is a maximum allowable closure amount for particle contact. Therefore, the compression of particle contact is a hardening process, and its deformation satisfies the following constitutive relationship:

[0048] in, represents the particle contact force, represents the particle closure amount, represents the initial compressive stiffness, Indicates the maximum allowable closure amount of the particle.

[0049] like Figure 5 As shown, this is a schematic diagram of the deformation constitutive model of loaded particles represented by the contact force-displacement curve during the first loading process. Figure 5 The constitutive model of particle deformation during loading is shown, which is expressed by the contact force-displacement curve. The curve shows a linear growth in the initial stage, representing elastic deformation, and then increases nonlinearly to a peak point, indicating yielding to the maximum contact force. Figure 5 The arrow in the figure indicates the particle loading direction, and the arrows in other figures have the same meaning.

[0050] (2) Unloading particle deformation constitutive model.

[0051] A large amount of experimental research evidence shows that the unloading stress closure curve of rock will significantly deviate from the loading stress closure curve (such as Figure 2 Its deformation satisfies the following constitutive relation:

[0052] in, represents a dimensionless parameter, is a dimensionless parameter representing stress, The closing quantity representing the transition from loading to unloading state, and They are all positive numbers, and their specific values ​​are determined in the process of optimizing the compression hardening loading and unloading model.

[0053] The unloading curve first changes basically linearly, and then tends to be nonlinear as the compressive stress decreases. The results show that the filling fracture stiffness increases during unloading compared to the loading condition. Finally, when the compressive stress is reduced to 0, there is plastic deformation (irreversible closure). At this point, a cycle of rock loading / unloading / reloading is completed. When loaded and unloaded again, the stress path is similar to the first cycle. The study found that a specific experimental unloading stress closure curve can also be fitted by the BB model. However, since related parameters, such as stiffness, the maximum allowable closure of particles and the irreversible closure of particles are highly dependent on the stress state, it is difficult to quantitatively characterize the unloading curve under any stress state. It is also for this problem that the present application proposes the above-mentioned constitutive model, which considers the loading / unloading effect on the basis of the BB model. As Figure 6 As shown in the figure, it is a schematic diagram of the unloading particle deformation constitutive model represented by the contact force-displacement curve during the unloading process. Figure 6 The arrow in the middle indicates the loading direction. Figure 6 It can be seen that in the unloading direction, the curve shows the particle from the maximum displacement (corresponding to the maximum allowable closure of the particle ) gradually recovers to a smaller displacement. In this process, the particle contact force As the particle closure decreases gradually.

[0054] like Figure 7 As shown in Figure 1, it is a schematic diagram of the particle deformation constitutive model represented by the stress-displacement curve during the cyclic loading and unloading process. Figure 7 It can be seen that the constitutive model of particle contact during cyclic loading and unloading is intuitively expressed by the contact force-displacement curve. Figure 7 In the particle contact force It is the core research object. During the loading stage, the contact force increases with the particle closure amount. The contact force of the particles increases gradually with the increase of Begins to decrease, and the particle closure The particle is in an "unloaded state". Figure 7 This is also graphically demonstrated by the circles and arrows on the right. (3) Tensile deformation constitutive model.

[0055] Most of the particles inside the rock are bonded together, and the contact boundary of the particles can withstand tensile stress. Its tensile failure is a progressive failure process, which will experience the initiation of microcracks, the accumulation of microcracks and the final fracture. However, the nonlinear effect caused by the softening deformation of the rock studied in this application is not prominent, so the softening deformation of the particle contact under tension is not considered, and the following relationship is satisfied:

[0056] in, represents the tensile stress of the particle contact, represents the tensile displacement of the particle contact, represents the tensile stiffness of the particle contact, represents the tensile strength of particle contact, Indicates tensile fracture.

[0057] (4) Shear deformation constitutive model.

[0058] Rough joints and filled joints generally produce softening deformation when subjected to shear loads, which contributes to the shear-induced progressive failure (degradation) of the micro-convex bodies or filling particles of the joints, causing the shear stiffness to gradually decrease. However, the nonlinear effect caused by softening deformation is not prominent, so it is not considered, and it satisfies the following relationship:

[0059] in, represents the shear stress of the particle contact, represents the constant shear stiffness of the particle contact, represents the shear displacement of the particle contact, represents the compressive stress of the particle contact, represents the friction angle of particle contact, represents the shear strength, Represents the cohesion of particle contact.

[0060] 2. Simulation and analysis: Combined with the particle model method based on PFC2D6.0, the rock loading and unloading response simulation method of this application is converted into an executable simulation program to observe and record the mechanical behavior of rock under cyclic loading and unloading conditions, including stress-strain relationship, compression hardening behavior, microscopic nonlinear stress state characteristics, etc.

[0061] like Figure 8 As shown in the figure, it is a schematic diagram of the stress-strain curve results of the rock sample loading-unloading-reloading failure simulation. Fig. 9 The figure shows the stress-strain curve results of multiple cycles of loading and unloading simulation. Figure 8 It can be seen that the curve shows an upward trend in the initial loading stage and exhibits extremely strong nonlinear behavior, indicating that as the strain increases, the stress on the rock sample also increases. Subsequently, the curve shows a period of decline, which represents the unloading process, that is, the stress on the rock sample is gradually decreasing. Then, the curve rises again, showing the stress-strain relationship of the rock sample during the reloading process. This result is consistent with Figure 1 The changing trends of the experimental results are highly similar, which further illustrates the accuracy and practicality of the innovation of this application. Fig. 9 In the figure, arrows of different sizes reflect the dynamic change direction of the curve (loading or unloading). The change trend of each stress path in the curve during multiple cycles of loading, unloading and reloading is similar to Figure 2 The results are highly consistent and also reproduce the mechanical response of rock materials in this process, which further verifies the accuracy and reliability of this application.

[0062] like Fig.10 FIG. 1 is a schematic diagram of a rock loading and unloading response simulation system of the present application, which may include: The first model building module is used to build a corresponding discrete element particle model according to the rock parameters to be measured; The second model building module is used to build a compression hardening loading and unloading model; the compression hardening loading and unloading model includes a loading particle deformation constitutive model, an unloading particle deformation constitutive model, a tensile deformation constitutive model and a shear deformation constitutive model; The parameter optimization module is used to simulate the loading and unloading response of the rock to be tested multiple times based on the discrete element particle model and the compression hardening loading and unloading model to obtain the corresponding simulation results, and to actually measure the rock to be tested after each loading and unloading response simulation, and to optimize the variable parameters of the compression hardening loading and unloading model according to the difference between the simulation results and the actual measurement results, until the difference between the simulation results and the actual measurement results meets the preset requirement range, thereby obtaining the optimized compression hardening loading and unloading model; The simulation module is used to simulate the loading and unloading response of the rock parameters to be tested based on the discrete element particle model and the optimized compression hardening loading and unloading model.

[0063] It should be noted that in the several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the system embodiments described above are merely schematic. For example, the division of each module is only a logical function division. There may be other division methods in actual implementation. For example, multiple modules can be combined or integrated into another device, or some features can be ignored or not executed. The module described as a separate component may or may not be physically separated. The component displayed as a module may be a physical unit or multiple physical units, that is, it may be located in one place, or it may be distributed in multiple different places. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment.

[0064] In addition, each module in each embodiment of the present invention may be integrated into a processing unit, each module may exist physically separately, or two or more modules may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of a software functional unit.

[0065] An embodiment of the present application also provides an electronic device, which may include one or more processors, a memory, and a communication interface.

[0066] The memory, the communication interface and the processor are coupled, for example, the memory, the communication interface and the processor may be coupled together via a bus.

[0067] The communication interface is used for data transmission with other devices. The memory stores computer program code. The computer program code includes computer instructions, and when the computer instructions are executed by the processor, the electronic device executes the steps of the rock loading and unloading response simulation method.

[0068] Wherein, the processor can be a processor or a controller, for example, a central processing unit (CPU), a general processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, transistor logic devices, hardware components or any combination thereof. It can implement or execute various exemplary logic blocks, modules and circuits described in conjunction with the present disclosure. The processor can also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of DSP and microprocessors, and the like. The processor can be used to support electronic devices to execute the method steps provided in the above embodiments.

[0069] The bus may be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. The above bus may be divided into an address bus, a data bus, a control bus, etc.

[0070] An embodiment of the present application provides a computer-readable storage medium, in which a computer program is stored. When the computer program is executed by a processor, the steps of the above-mentioned rock loading and unloading response simulation method are implemented.

[0071] The computer-readable storage medium involved in the present application includes random access memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disks, removable disks, CD-ROMs, or any other form of storage medium known in the technical field.

[0072] For the description of the relevant parts of the rock loading and unloading response simulation system, electronic device and computer-readable storage medium provided in the embodiments of the present application, please refer to the detailed description of the corresponding parts in the rock loading and unloading response simulation method provided in the embodiments of the present application, which will not be repeated here. In addition, the parts of the above technical solutions provided in the embodiments of the present application that are consistent with the implementation principles of the corresponding technical solutions in the prior art are not described in detail to avoid excessive elaboration.

[0073] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for simulating rock loading and unloading response, characterized in that: include: According to the rock parameters to be measured, the corresponding discrete element particle model is established; Constructing a compression hardening loading and unloading model; the compression hardening loading and unloading model includes a loading particle deformation constitutive model, an unloading particle deformation constitutive model, a tensile deformation constitutive model and a shear deformation constitutive model; Based on the discrete element particle model and the compression hardening loading and unloading model, the loading and unloading response simulation of the rock to be tested is performed multiple times to obtain the corresponding simulation results, and the rock to be tested is actually measured after each loading and unloading response simulation. According to the difference between the simulation results and the actual measurement results, the variable parameters of the compression hardening loading and unloading model are optimized until the difference between the simulation results and the actual measurement results meets the preset requirement range, thereby obtaining the optimized compression hardening loading and unloading model; Based on the discrete element particle model and the optimized compression hardening loading and unloading model, the loading and unloading response simulation of the rock parameters to be tested is carried out.

2. The rock loading and unloading response simulation method according to claim 1 is characterized in that: The loaded particle deformation constitutive model comprises: in, represents the particle contact force, represents the particle closure amount, represents the initial compressive stiffness, Indicates the maximum allowable closure amount of the particle.

3. The rock loading and unloading response simulation method according to claim 2 is characterized in that: The unloading particle deformation constitutive model includes: in, represents a dimensionless parameter, represents the dimensionless parameter of stress, The closing quantity representing the transition state from loading to unloading; and Both are greater than zero.

4. The rock loading and unloading response simulation method according to claim 3 is characterized in that: The tensile deformation constitutive model comprises: in, represents the tensile stress of the particle contact, represents the tensile displacement of the particle contact, represents the tensile stiffness of the particle contact, represents the tensile strength of particle contact, Indicates tensile fracture.

5. The rock loading and unloading response simulation method according to claim 4 is characterized in that: The shear deformation constitutive model comprises: in, represents the shear stress of the particle contact, represents the shear stiffness of the particle contact, represents the shear displacement of the particle contact, represents the compressive stress of the particle contact, represents the friction angle of particle contact, Indicates shear fracture, Represents the cohesion of particle contact.

6. The rock loading and unloading response simulation method according to claim 5 is characterized in that: The variable parameters of the optimized compression hardening loading and unloading model include: initial compression stiffness , Maximum allowable closure amount of particles , dimensionless parameters , stress parameters of the same dimension , the tensile stiffness of the particle contact , shear stiffness of particle contact , tensile strength of particle contact , the friction angle of particle contact Cohesion of contact with particles .

7. The rock loading and unloading response simulation method according to claim 1 is characterized in that: The discrete element particle model is based on PFC2D software and is implemented through secondary development using C++ language programming; The compression hardening loading and unloading model generates a dynamic link library file by compiling, and when the compression hardening loading and unloading model is used, it is called through the PFC2D software.

8. A rock loading and unloading response simulation system, characterized in that: include: The first model building module is used to build a corresponding discrete element particle model according to the rock parameters to be measured; The second model building module is used to build a compression hardening loading and unloading model; the compression hardening loading and unloading model includes a loading particle deformation constitutive model, an unloading particle deformation constitutive model, a tensile deformation constitutive model and a shear deformation constitutive model; The parameter optimization module is used to simulate the loading and unloading response of the rock to be tested multiple times based on the discrete element particle model and the compression hardening loading and unloading model to obtain the corresponding simulation results, and to actually measure the rock to be tested after each loading and unloading response simulation, and to optimize the variable parameters of the compression hardening loading and unloading model according to the difference between the simulation results and the actual measurement results, until the difference between the simulation results and the actual measurement results meets the preset requirement range, thereby obtaining the optimized compression hardening loading and unloading model; The simulation module is used to simulate the loading and unloading response of the rock parameters to be tested based on the discrete element particle model and the optimized compression hardening loading and unloading model.

9. An electronic device, characterized in that: include: A memory and one or more processors; the memory is coupled to the processor; wherein the memory stores computer program code, the computer program code includes computer instructions, and when the computer instructions are executed by the processor, the electronic device executes the steps of the rock loading and unloading response simulation method as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the rock loading and unloading response simulation method as claimed in any one of claims 1 to 7 are implemented.

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