Chamber excavation surrounding rock failure area simulation method and related equipment

Abstract

The invention discloses a chamber excavation surrounding rock failure area simulation method and related equipment, and relates to the field of geotechnical engineering stability evaluation.The method comprises the steps that an underground chamber excavation process is simulated through an underground chamber initial model without setting support measures, a plastic zone range is obtained, and principal stress information of a corresponding unit of a failure area is extracted; calculating the damage degree of the surrounding rock based on the surrounding rock stress state; performing zoning operation on the damage area according to the surrounding rock damage degree to obtain refined zoning information; on the basis of a triaxial compression test, rock mechanical parameters related to the residual strength of the surrounding rock under different damage degrees are obtained; assigning values to different partitions with different damage degrees according to the rock mechanical parameters related to the residual strength; and excavation numerical simulation is conducted again to obtain a new plastic zone range and main stress distribution, and final partition assignment and refined simulation are completed. According to the method, the authenticity, engineering adaptability and reliability of numerical simulation are improved, and the method has clear technical progress and engineering practical value.

Description

Technical Field

[0001] This specification relates to the field of geotechnical engineering stability evaluation, and more specifically, the present application relates to a method for simulating the surrounding rock failure zone of a chamber excavation and related equipment. Background Art

[0002] During underground construction, surrounding rock deformation and failure are key issues in project safety control, especially in the construction of deeply buried structures such as tunnels, mines, and man-made chambers. As underground excavation progresses, the in-situ rock stress field is disturbed, causing stress redistribution in the surrounding rock. Unloading failure can occur in localized areas, leading to loosening, collapse, and rockfall, seriously compromising the stability of the structure and construction safety.

[0003] Currently, numerical simulations of underground engineering projects generally use fixed rock mass parameters for modeling, failing to fully account for the degradation of the surrounding rock's mechanical properties during excavation. In reality, rock undergoes significant strain softening when stress exceeds its strength limit, with strength parameters (such as cohesion and internal friction angle) continuously degrading with accumulated plastic strain. Traditional models ignore this physical evolutionary process, resulting in simulation results that often fail to accurately reflect the progressive failure behavior and residual strength characteristics of the surrounding rock, significantly differing from field monitoring data.

[0004] Furthermore, existing research and laboratory tests have shown that the residual strength of a rock mass depends not only on its material properties but also on the combined influence of the confining pressure level and the plastic strain increment. Therefore, the degradation process of rock mass parameters in the failure zone exhibits significant spatial differentiation, meaning that rock mass parameters at different locations within the plastic zone should experience varying degrees of degradation. However, a systematic method for rationally and operationally zoning and accurately assigning spatial parameters to the failure zone of surrounding rock in underground chambers is currently lacking, resulting in significant local errors in simulation results and failing to meet the requirements for high-precision underground engineering design and construction simulation.

[0005] Therefore, it is urgent to propose a simulation method for the surrounding rock failure zone of chamber excavation to improve the accuracy of the simulation results and engineering applicability. Summary of the Invention

[0006] The Summary of the Invention introduces a series of simplified concepts that will be further described in the Detailed Description of the Invention. The Summary of the Invention of this application is not intended to limit the key features and essential technical features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0007] In a first aspect, the present application proposes a method for simulating the surrounding rock failure zone of a chamber excavation, comprising: S1. Establish the initial model of the underground chamber; S2. Using the above-mentioned initial model of the underground chamber without setting any support measures, simulate the excavation process of the underground chamber, obtain the range of the plastic zone, and extract the principal stress information of the units corresponding to the failure zone; S3. Calculate the degree of surrounding rock damage based on the surrounding rock stress state; S4. Partitioning the damaged area according to the surrounding rock damage degree to obtain refined partition information, wherein the refined partition information includes different partition information of different damage degrees; S5. Based on triaxial compression tests, obtain rock mechanical parameters related to the residual strength of surrounding rock at different damage levels; S6. Assign values ​​to different zones with different degrees of damage according to the rock mechanics parameters related to the residual strength mentioned above; S7. Re-perform the excavation numerical simulation to obtain the new plastic zone range and principal stress distribution; S8. Repeat steps S4 to S7 until the surrounding rock partition assignment near the cavern is completed to complete the final partition assignment and refined simulation.

[0008] In a feasible implementation, the above-mentioned initial model of the underground chamber adopts an ideal elastic-plastic model. The above-mentioned initial model of the underground chamber gives initial rock mechanical parameters based on the Mohr-Coulomb constitutive relationship, and applies boundary conditions and initial ground stresses.

[0009] In a feasible embodiment, the rock mechanics parameters related to the residual strength include cohesion and internal friction angle.

[0010] In a feasible implementation, the rock mechanical parameters related to the residual strength of the surrounding rock at different damage degrees are obtained based on the triaxial compression test, including: S51. Determine the confining pressure range based on the principal stress information and divide the confining pressure into equal steps; S52. Collect rock samples at the project site and conduct multiple sets of triaxial compression tests at a constant loading rate under a specific confining pressure. Obtain the ultimate plastic strain of the rock samples through the stress-strain curve. S53, selecting a new rock sample, loading it at a standard rate under the above confining pressure range until the rock fails, and continuously loading it to a predetermined plastic strain threshold before uniformly unloading; S54, reloading the new rock sample after unloading, and determining its residual strain value through a new stress-strain curve; S55, changing the confining pressure value, repeating steps S52 to S54, and obtaining rock residual strength and residual strain data under multiple confining pressures; S56. Based on the rock residual strength and the residual strain data, draw Mohr stress circles under different stress states, wherein the center of the Mohr stress circle is the average principal stress and the radius is the shear stress; S57. Fit the residual strength surface to determine the rock mechanics parameters related to the residual strength.

[0011] In a feasible implementation, the initial model of the underground chamber is meshed using Rhino software and Griddle plug-in, and numerical simulation is performed using FLAC3D software.

[0012] In a feasible implementation, in the process of assigning values ​​to different partitions with different degrees of damage, different regional units are assigned different rock parameters, and units in the same region are assigned the same rock parameters. The above rock parameters include elastic modulus, cohesion, Poisson's ratio and internal friction angle.

[0013] In a feasible implementation manner, the above-mentioned surrounding rock failure degree is determined based on plastic shear strain and ultimate plastic shear strain.

[0014] In a second aspect, the present invention further provides a device for simulating a rock failure zone in a chamber excavation, comprising: Establishing units for building an initial model of the underground chamber; The first simulation unit is used to simulate the excavation process of the underground chamber without setting any support measures using the above-mentioned initial model of the underground chamber, obtain the range of the plastic zone, and extract the principal stress information of the unit corresponding to the failure zone; A calculation unit, used to calculate the degree of surrounding rock damage based on the surrounding rock stress state; A first acquiring unit is configured to partition the damaged area according to the surrounding rock damage degree to acquire refined partition information, wherein the refined partition information includes different partition information of different damage degrees; The second acquisition unit is used to obtain rock mechanical parameters related to the residual strength of the surrounding rock at different damage degrees based on triaxial compression tests; An assignment unit is used to assign values ​​to different partitions with different degrees of damage according to the rock mechanics parameters related to the residual strength; The second simulation unit is used to re-perform the excavation numerical simulation to obtain the new plastic zone range and principal stress distribution; The iteration unit is used to repeat the steps from the acquisition unit to the second simulation unit until the partition assignment of the surrounding rock near the cavern is completed, so as to complete the final partition assignment and refined simulation.

[0015] In a third aspect, the present invention further proposes an electronic device comprising: a memory and a processor, characterized in that the processor is used to implement the steps of the method for simulating the surrounding rock damage zone of chamber excavation as described in any one of the first aspects when executing the computer program stored in the memory.

[0016] In a fourth aspect, the present invention further proposes a computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, the steps of the method for simulating the surrounding rock damage zone of a chamber excavation are implemented as described in any one of the first aspects.

[0017] In summary, existing numerical simulation methods often use fixed rock mechanical parameters, failing to reflect the evolution of rock damage under excavation disturbance. This example introduces the surrounding rock failure degree (FD) as a quantitative indicator of damage severity, combined with a dynamic calculation of the ratio of plastic shear strain to ultimate shear strain. This, for the first time, incorporates a dynamic degradation mechanism into the simulation process, where parameters change with spatial location and damage state. This effectively overcomes the shortcomings of conventional models in their crude characterization of rock behavior. This method categorizes the damage zone into grades and spatially assigns values ​​based on measured data of rock mechanical parameters (such as cohesion and internal friction angle) at different damage levels. This method creates a geologically plausible parameter distribution gradient within the plastic zone, enhancing the consistency of numerical simulation results with actual engineering conditions and providing more accurate input data for regional stability assessment. This example uses standard triaxial compression tests to obtain residual strength parameters under different confining pressures and failure states, ensuring a clear and reliable source for the assigned values. Furthermore, multiple cycles of loading, unloading, and reloading experimental paths are used to capture the true mechanical response of rock after degradation, ensuring the authenticity and scientific validity of the model parameters from the source. An iterative convergent analysis mechanism is constructed through a closed-loop process of degree of destruction-zoning-mechanical parameter extraction-region assignment-re-simulation. This mechanism allows for dynamic correction of parameters and plastic zone distribution in each round of simulation until the model is stable, significantly improving the robustness of the simulation and its adaptability to complex excavation scenarios. This method does not rely on specific engineering scenarios and can be widely used in numerical simulation and support optimization analysis of underground projects such as ultra-large span chambers, deep buried tunnels, and mine tunnels. It has good prospects for engineering promotion and general applicability. In summary, the present invention effectively solves the problems of unreasonable parameter assignment of surrounding rock of underground chambers and insufficient accuracy of simulation results in the prior art, significantly improves the authenticity, engineering adaptability and reliability of numerical simulation, and has clear technological advancement and engineering practical value.

[0018] Other advantages, objectives and features of the present application will be reflected in part through the following description, and in part will be understood by those skilled in the art through study and practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present description. The same reference symbols are used throughout the drawings to represent the same components. In the drawings: Figure 1A schematic flow chart of a method for simulating a rock failure zone in a chamber excavation according to an embodiment of the present application; Figure 2 A schematic diagram of a process for obtaining rock mechanical parameters provided in an embodiment of the present application; Figure 3 A schematic diagram of a Mohr strength curve of a rock provided in an embodiment of the present application; Figure 4 A schematic structural diagram of a device for simulating a rock failure zone in a chamber excavation provided in an embodiment of the present application; Figure 5 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0020] The terms "first", "second", "third", "fourth", etc. (if any) in the specification and claims of this application and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate so that the embodiments described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices. The technical solutions 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 embodiments described are only some embodiments of the present application, not all embodiments.

[0021] See also Figure 1 , which is a schematic diagram of the process of simulating the surrounding rock failure zone of a chamber excavation provided in an embodiment of the present application, which may specifically include: In a first aspect, the present application proposes a method for simulating the surrounding rock failure zone of a chamber excavation, comprising: S1. Establish the initial model of the underground chamber; S2. Using the above-mentioned initial model of the underground chamber without setting any support measures, simulate the excavation process of the underground chamber, obtain the range of the plastic zone, and extract the principal stress information of the units corresponding to the failure zone; S3. Calculate the degree of surrounding rock damage based on the surrounding rock stress state; S4. Partitioning the damaged area according to the surrounding rock damage degree to obtain refined partition information, wherein the refined partition information includes different partition information of different damage degrees; S5. Based on triaxial compression tests, obtain rock mechanical parameters related to the residual strength of surrounding rock at different damage levels; S6. Assign values ​​to different zones with different degrees of damage according to the rock mechanics parameters related to the residual strength mentioned above; S7. Re-perform the excavation numerical simulation to obtain the new plastic zone range and principal stress distribution; S8. Repeat steps S4 to S7 until the surrounding rock partition assignment near the cavern is completed to complete the final partition assignment and refined simulation.

[0022] For example, in step S1, an initial three-dimensional numerical model of the underground chamber is established. This model is constructed based on actual geological conditions, employing an ideal elastic-plastic constitutive model and combining the Mohr-Coulomb strength criterion to set initial rock mass parameters. By properly dividing the grid, defining boundary conditions and the initial geostress field, this provides a foundational environment for subsequent simulations.

[0023] In step S2, a numerical simulation of the excavation process of the underground chamber model is performed without any support structures. The simulation accurately reflects the mechanical response of the surrounding rock after disturbance, extracts the distribution range of the surrounding rock plastic zone, and records the principal stress values ​​of the failure zone elements (including the maximum principal stress σ1, the intermediate principal stress σ2, and the minimum principal stress σ3).

[0024] In step S3, based on the principal stress information, the surrounding rock failure degree (FD) of each element is calculated. This failure degree reflects the degree of damage to the rock mass and is calculated based on the ratio of the plastic shear strain to the material's ultimate shear strain. A higher failure degree indicates more severe rock mass damage.

[0025] Proceeding to step S4, the damaged area is finely partitioned based on the spatial distribution of damage values. Specifically, the damaged area is divided into several levels, such as slight damage, moderate damage, and severe damage, forming a discriminative "zoning map." This map will provide a basis for subsequent parameter assignment.

[0026] In step S5, standard indoor triaxial compression tests are conducted to determine the residual strength parameters of the rock mass in each failure zone, including cohesion (c) and internal friction angle (φ). The test process involves loading the rock mass under different confining pressures until failure, then continuing to load it to a set plastic strain threshold, unloading it, and reloading it to obtain the residual stress-strain curve of the rock mass.

[0027] Then, in step S6, the mechanical parameters corresponding to the different degrees of damage obtained in the above experiments are assigned to each region within the fine-scale partition. In other words, independent rock parameters are set for each damage level and uniformly assigned to all elements within the corresponding region, allowing the simulation model to truly reflect the spatial variation of the rock mass's mechanical properties.

[0028] In step S7, after the partitions are assigned, the numerical excavation simulation is re-run. This round of simulation is based on a new parameter system, demonstrating more realistic characteristics of the plastic zone expansion and principal stress changes. The system outputs the new failure zone range and stress state, providing input data for the next round of optimization.

[0029] Finally, in step S8, the aforementioned steps S4 to S7 are iterated, and the cycle of “destruction degree calculation-zoning-mechanical parameter acquisition-parameter assignment-numerical simulation” is continuously performed until the model response tends to be stable, that is, the iteration is terminated when the change in the plastic zone and the change in the principal stress are lower than the set threshold.

[0030] In summary, existing numerical simulation methods often use fixed rock mechanical parameters, failing to reflect the evolution of rock damage under excavation disturbance. This example introduces the surrounding rock failure degree (FD) as a quantitative indicator of damage severity, combined with a dynamic calculation of the ratio of plastic shear strain to ultimate shear strain. This, for the first time, incorporates a dynamic degradation mechanism into the simulation process, where parameters change with spatial location and damage state. This effectively overcomes the shortcomings of conventional models in their crude characterization of rock behavior. This method categorizes the damage zone into grades and spatially assigns values ​​based on measured data of rock mechanical parameters (such as cohesion and internal friction angle) at different damage levels. This method creates a geologically plausible parameter distribution gradient within the plastic zone, enhancing the consistency of numerical simulation results with actual engineering conditions and providing more accurate input data for regional stability assessment. This example uses standard triaxial compression tests to obtain residual strength parameters under different confining pressures and failure states, ensuring a clear and reliable source for the assigned values. Furthermore, multiple cycles of loading, unloading, and reloading experimental paths are used to capture the true mechanical response of rock after degradation, ensuring the authenticity and scientific validity of the model parameters from the source. An iterative convergent analysis mechanism is constructed through a closed-loop process of degree of destruction-zoning-mechanical parameter extraction-region assignment-re-simulation. This mechanism allows for dynamic correction of parameters and plastic zone distribution in each round of simulation until the model is stable, significantly improving the robustness of the simulation and its adaptability to complex excavation scenarios. This method does not rely on specific engineering scenarios and can be widely used in numerical simulation and support optimization analysis of underground projects such as ultra-large span chambers, deep buried tunnels, and mine tunnels. It has good prospects for engineering promotion and general applicability. In summary, the present invention effectively solves the problems of unreasonable parameter assignment of surrounding rock of underground chambers and insufficient accuracy of simulation results in the prior art, significantly improves the authenticity, engineering adaptability and reliability of numerical simulation, and has clear technological advancement and engineering practical value.

[0031] In a feasible implementation, the above-mentioned initial model of the underground chamber adopts an ideal elastic-plastic model. The above-mentioned initial model of the underground chamber gives initial rock mechanical parameters based on the Mohr-Coulomb constitutive relationship, and applies boundary conditions and initial ground stresses.

[0032] In a feasible embodiment, the rock mechanics parameters related to the residual strength include cohesion and internal friction angle.

[0033] For example, to accurately simulate the deformation and failure of the surrounding rock of an underground chamber, an initial three-dimensional numerical model of the underground chamber is first constructed. This model uses an ideal elastic-plastic material model as the basis for the mechanical response of the rock mass, describing its elastic deformation and plastic yielding behavior under stress. This model can accurately reflect the entire process of the surrounding rock's evolution from an initial stable state to a damaged state.

[0034] Specifically, in this embodiment, the constitutive relationship of the rock mass is defined based on the Mohr-Coulomb strength criterion. The Mohr-Coulomb criterion is a shear failure criterion widely used in geotechnical engineering to describe the yield condition of a material under different principal stress combinations. This criterion expresses the shear strength of the rock mass as a function of cohesion (c) and internal friction angle (φ), effectively simulating the failure behavior of rock under different confining pressures.

[0035] During model construction, initial rock mass mechanical parameters, including elastic modulus (E), Poisson's ratio (ν), cohesion (c), internal friction angle (φ), and tensile strength, were set based on actual engineering geological survey results. These parameters were obtained through methods such as indoor triaxial compression testing, shear testing, and inversion analysis of rock samples to ensure that the parameters used in the simulation were representative of the actual situation.

[0036] Subsequently, the model's boundary conditions were set by applying reasonable constraints to ensure stable operation and establishing the initial geostress field for the stratum in which the underground structure resides. Initial geostresses typically include self-weight stress and tectonic stress, and can be applied based on measured data or empirical models of regional stress fields. Together, these boundary conditions and initial geostresses constitute the initial operating environment for the model, enabling numerical calculations to gradually deduce the rock mass's response based on the stress state before excavation of the actual underground project.

[0037] In a feasible implementation, the triaxial compression test is used to obtain rock mechanics parameters related to the residual strength of the surrounding rock at different damage levels. Figure 2 A schematic flow chart of a method for obtaining rock mechanical parameters provided in an embodiment of the present application specifically includes: S51. Determine the confining pressure range based on the principal stress information and divide the confining pressure into equal steps; S52. Collect rock samples at the project site and conduct multiple sets of triaxial compression tests at a constant loading rate under a specific confining pressure. Obtain the ultimate plastic strain of the rock samples through the stress-strain curve. S53, selecting a new rock sample, loading it at a standard rate under the above confining pressure range until the rock fails, and continuously loading it to a predetermined plastic strain threshold before uniformly unloading; S54, reloading the new rock sample after unloading, and determining its residual strain value through a new stress-strain curve; S55, changing the confining pressure value, repeating steps S52 to S54, and obtaining rock residual strength and residual strain data under multiple confining pressures; S56. Based on the rock residual strength and the residual strain data, draw Mohr stress circles under different stress states, wherein the center of the Mohr stress circle is the average principal stress and the radius is the shear stress; S57. Fit the residual strength surface to determine the rock mechanics parameters related to the residual strength.

[0038] For example, first, in step S51, a reasonable range of confining pressure values ​​is determined based on the principal stress information in the failure zone obtained from the previous simulation. Considering that the residual strength characteristics of rock are significantly affected by confining pressure, to ensure data coverage of different degrees of failure, the confining pressure is divided into several equally spaced steps (e.g., low confining pressure, medium confining pressure, and high confining pressure) to establish a comparison data set under multiple stress states.

[0039] Next, in step S52, representative rock samples from the actual project area are selected and multiple sets of triaxial compression tests are conducted in the laboratory under simulated confining pressure conditions. In each set of tests, a constant loading rate is applied to gradually stress the rock sample until failure occurs. At the same time, complete stress-strain curve data is recorded, and the ultimate plastic strain of the rock sample is extracted from it. , that is, its maximum plastic deformation capacity before instability.

[0040] Then, in step S53, a new rock sample is selected and loaded at a standard loading rate under the same confining pressure conditions, and the loading is continued until the rock mass failure point, and then the loading is continued until a preset plastic strain threshold value. The strain is usually greater than the ultimate plastic strain to simulate the real deep failure state of the rock mass. After reaching the threshold, uniform unloading is performed to study the residual structural characteristics of the rock sample after unloading.

[0041] In step S54, the loading force is applied to the unloaded rock sample again, and the residual strain value of the rock sample is obtained by the second stress-strain curve analysis. and degree of damage : It is used to reflect the load-bearing capacity of rock mass after failure. This process can effectively evaluate the structural degradation law of rock under different stress paths.

[0042] Then, in step S55, the confining pressure value is changed and steps S52 to S54 are repeated to form a data set of residual strength and residual strain under multiple confining pressure states. This experimental sequence can fully reflect the changes in the mechanical properties of the rock mass from the initial intact state to different damage degrees. Repeat the experiment step 3 to get different results. Through different and maintain a constant , draw the Mohr circle under different stress states, Figure 3 A schematic diagram of the Mohr strength curve of a rock provided in the embodiment of the present application, the coordinates of the center of the Mohr circle are , the radius is ; Then the residual strength surface is obtained, and the mechanical parameters of the residual rock after destruction are further analyzed, namely cohesion c, internal friction angle .

[0043] Finally, in step S57, a residual strength envelope curve or surface is constructed based on the above-mentioned Mohr circle, and further regression fitting and analysis of mechanical parameters such as the residual cohesion (c) and internal friction angle (φ) of the rock are performed to form a mapping relationship of mechanical parameters under different damage levels. These fitting results can be used in the fine assignment model to assign more realistic physical parameters to the rock mass in different damage zones. After the experiment is completed, the c, Values ​​are assigned to each partition separately, that is, different regional units are assigned different rock parameters, and units in the same region are assigned the same rock parameters; In summary, this embodiment comprehensively quantifies the mechanical degradation process of rock mass under different confining pressures and failure conditions through a standardized and systematic triaxial compression test process combined with an unloading-reloading path. This effectively supports the subsequent parameter degradation assignment of surrounding rock zoning, greatly improving the engineering credibility and calculation accuracy of the model.

[0044] In a feasible implementation, the initial model of the underground chamber is meshed using Rhino software and Griddle plug-in, and numerical simulation is performed using FLAC3D software.

[0045] In a feasible implementation, in the process of assigning values ​​to different partitions with different degrees of damage, different regional units are assigned different rock parameters, and units in the same region are assigned the same rock parameters. The above rock parameters include elastic modulus, cohesion, Poisson's ratio and internal friction angle.

[0046] In a feasible implementation manner, the above-mentioned surrounding rock failure degree is determined based on plastic shear strain and ultimate plastic shear strain.

[0047] For example, to achieve high-precision simulation of the failure behavior of the surrounding rock of an underground chamber, a three-dimensional numerical model of the underground chamber area was first established and a reasonable mesh was applied. During the model construction process, Rhino modeling software combined with the Griddle plug-in was used for geometric modeling and mesh generation of complex geological structures. This combination offers excellent model representation capabilities and high-quality meshing, making it particularly suitable for underground engineering scenarios with complex structures and irregular geometries. After meshing, the model was imported into FLAC3D (Fast Lagrangian Analysis of Continua in 3 Dimensions) finite-difference numerical simulation software for subsequent simulation calculations. FLAC3D is capable of handling geotechnical elastic-plastic problems and can simulate stress changes, deformation responses, and the development of plastic zones during different excavation stages, making it an effective tool for geomechanical analysis of underground engineering.

[0048] After the model is established and the boundary conditions and initial stress field are loaded, the unsupported excavation simulation of the underground chamber is carried out. As the excavation progresses, the rock mass stress redistributes, causing localized damage and forming plastic zones. In this process, the principal stress information (σ1, σ2, σ3) and strain values ​​of the plastic unit are extracted to further calculate the degree of failure (FD) of the surrounding rock. The rock failure degree FD is calculated by formula (3): Where, is the plastic shear strain, is the ultimate plastic shear strain of the material. = , plastic deviatoric strain = ; Based on the spatial distribution of damage, the surrounding rock mass is finely zoned in the model, typically into zones of light damage, moderate damage, and severe damage. Each zone represents a different degree of rock mass damage, and parameter values ​​are assigned accordingly.

[0049] For example, different rock mechanical parameters are assigned to different partitions with different degrees of damage. The specific approach is: different regional units are assigned different parameter values, and all units within the same region are assigned the same parameter values ​​to ensure that the parameter distribution has physical consistency and computational simplicity. The assigned rock parameters mainly include: elastic modulus is used to reflect the stiffness and elastic deformation capacity of the rock mass; cohesion is used to represent the bonding ability between particles within the rock mass, which is an important component of shear strength; Poisson's ratio is used to describe the ratio between the lateral and axial strains of the rock mass; the internal friction angle is used to measure the magnitude of the slip resistance between particles of the rock mass under shear state. The values ​​of these parameters are based on the fitting results of the residual strength data curve obtained by the triaxial compression test mentioned above, thereby achieving parameter degradation expression consistent with the real engineering in different damage areas.

[0050] In summary, this implementation method achieves accurate simulation of the deformation and failure process of the surrounding rock of underground chambers through high-quality modeling tools, a high-performance computing platform, experimental data support, and a refined assignment mechanism based on the degree of destruction, providing a scientific basis for engineering design optimization and support scheme selection.

[0051] In the second aspect, the present invention also proposes a device for simulating the surrounding rock damage zone of a chamber excavation, such as Figure 4 As shown, including: Establishing unit 21 for establishing an initial model of the underground chamber; The first simulation unit 22 is used to simulate the underground chamber excavation process without setting support measures using the above-mentioned underground chamber initial model, obtain the range of the plastic zone, and extract the principal stress information of the unit corresponding to the failure zone; A calculation unit 23 is used to calculate the degree of surrounding rock damage based on the surrounding rock stress state; An acquisition unit 24 is configured to partition the damaged area according to the surrounding rock damage degree to obtain refined partition information, wherein the refined partition information includes different partition information of different damage degrees; The second acquisition unit 25 is used to obtain rock mechanical parameters related to the residual strength of the surrounding rock at different damage degrees based on the triaxial compression test; An assignment unit 26 is used to assign values ​​to different partitions with different degrees of damage according to the rock mechanics parameters related to the residual strength; The second simulation unit 27 is used to re-perform the excavation numerical simulation to obtain a new plastic zone range and principal stress distribution; The iterative unit 28 is used to repeat the steps from the acquisition unit 24 to the second simulation unit 27 until the partition assignment of the surrounding rock near the cavern is completed, so as to complete the final partition assignment and refined simulation.

[0052] In a feasible implementation, the above-mentioned initial model of the underground chamber adopts an ideal elastic-plastic model. The above-mentioned initial model of the underground chamber gives initial rock mechanical parameters based on the Mohr-Coulomb constitutive relationship, and applies boundary conditions and initial ground stresses.

[0053] In a feasible embodiment, the rock mechanics parameters related to the residual strength include cohesion and internal friction angle.

[0054] In a feasible implementation, the rock mechanical parameters related to the residual strength of the surrounding rock at different damage degrees are obtained based on the triaxial compression test, including: S51. Determine the confining pressure range based on the principal stress information and divide the confining pressure into equal steps; S52. Collect rock samples at the project site and conduct multiple sets of triaxial compression tests at a constant loading rate under a specific confining pressure. Obtain the ultimate plastic strain of the rock samples through the stress-strain curve. S53, selecting a new rock sample, loading it at a standard rate under the above confining pressure range until the rock fails, and continuously loading it to a predetermined plastic strain threshold before uniformly unloading; S54, reloading the new rock sample after unloading, and determining its residual strain value through a new stress-strain curve; S55, changing the confining pressure value, repeating steps S52 to S54, and obtaining rock residual strength and residual strain data under multiple confining pressures; S56. Based on the rock residual strength and the residual strain data, draw Mohr stress circles under different stress states, wherein the center of the Mohr stress circle is the average principal stress and the radius is the shear stress; S57. Fit the residual strength surface to determine the rock mechanics parameters related to the residual strength.

[0055] In a feasible implementation, the initial model of the underground chamber is meshed using Rhino software and Griddle plug-in, and numerical simulation is performed using FLAC3D software.

[0056] In a feasible implementation, in the process of assigning values ​​to different partitions with different degrees of damage, different regional units are assigned different rock parameters, and units in the same region are assigned the same rock parameters. The above rock parameters include elastic modulus, cohesion, Poisson's ratio and internal friction angle.

[0057] In a feasible implementation manner, the above-mentioned surrounding rock failure degree is determined based on plastic shear strain and ultimate plastic shear strain.

[0058] In a third aspect, the present invention further provides an electronic device 300, such as Figure 5As shown, it includes a memory 310, a processor 320 and a computer program 311 stored in the memory 310 and executable on the processor. When the processor 320 executes the computer program 311, the steps of the method for simulating the surrounding rock damage zone of chamber excavation as described in any one of the first aspects are implemented.

[0059] In a fourth aspect, the present invention further proposes a computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, the steps of the method for simulating the surrounding rock damage zone of a chamber excavation are implemented as described in any one of the first aspects.

[0060] It should be noted that, in the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant description of other embodiments.

[0061] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. Furthermore, the present application may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0062] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded computer, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0063] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0064] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0065] The present application also provides a computer program product including computer software instructions. When the computer software instructions are executed on a processing device, the processing device executes the voice-based identity recognition process in the corresponding embodiment. A computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, they fully or partially produce the processes or functions according to the embodiments of the present application. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that can be stored by a computer, or a data storage device such as a server or data center that integrates one or more available media. Available media can include magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., DVDs), or semiconductor media (e.g., solid-state drives (SSDs)).

[0066] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0067] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of units is only a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interface, device or unit, which can be electrical, mechanical or other forms.

[0068] Units described as separate components may or may not be physically separate, and components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0069] In addition, the functional units in the various embodiments of the present application may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0070] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a number of instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the various embodiments of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, and other media that can store program code.

[0071] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for simulating the surrounding rock failure zone of a chamber excavation, characterized in that: include: S1. Establish the initial model of the underground chamber; S2. Simulating the underground chamber excavation process by using the initial underground chamber model without setting any support measures, obtaining the range of the plastic zone, and extracting the principal stress information of the unit corresponding to the failure zone; S3. Calculate the degree of surrounding rock damage based on the surrounding rock stress state; S4. Partitioning the damaged area according to the degree of surrounding rock damage to obtain refined partition information, wherein the refined partition information includes different partition information of different degrees of damage; S5. Based on triaxial compression tests, obtain rock mechanical parameters related to the residual strength of surrounding rock at different damage levels; S6. Assigning values ​​to different partitions with different degrees of damage according to rock mechanics parameters related to the residual strength; S7. Re-perform the excavation numerical simulation to obtain the new plastic zone range and principal stress distribution; S8. Repeat steps S4 to S7 until the surrounding rock partition assignment near the cavern is completed to complete the final partition assignment and refined simulation.

2. A method for simulating a rock failure zone in a chamber excavation according to claim 1, characterized in that: The initial model of the underground chamber adopts an ideal elastic-plastic model. The initial model of the underground chamber is given initial rock mass mechanical parameters based on the Mohr-Coulomb constitutive relationship, and boundary conditions and initial ground stress are applied.

3. The method for simulating the surrounding rock failure zone of a chamber excavation according to claim 1, characterized in that: The rock mechanics parameters related to the residual strength include cohesion and internal friction angle.

4. A method for simulating a rock failure zone in a chamber excavation according to claim 1, characterized in that: The triaxial compression test is based on the rock mechanical parameters related to the residual strength of the surrounding rock at different damage degrees, including: S51, determining the confining pressure range according to the principal stress information, and dividing the confining pressure into equal steps; S52. Collect rock samples at the project site and conduct multiple sets of triaxial compression tests at a constant loading rate under a specific confining pressure. Obtain the ultimate plastic strain of the rock samples through the stress-strain curve. S53, selecting a new rock sample, loading it at a standard rate under the confining pressure range until the rock fails, and continuously loading it to a predetermined plastic strain threshold before uniformly unloading it; S54, reloading the new rock sample after unloading, and determining its residual strain value through a new stress-strain curve; S55, changing the confining pressure value, repeating steps S52 to S54, and obtaining rock residual strength and residual strain data under multiple confining pressures; S56. Based on the rock residual strength and the residual strain data, draw Mohr stress circles under different stress states, wherein the center of the Mohr stress circle is the average principal stress and the radius is the shear stress; S57. Fitting the residual strength surface to determine rock mechanics parameters related to the residual strength.

5. The method for simulating the surrounding rock failure zone of a chamber excavation according to claim 1, characterized in that: The initial model of the underground chamber was meshed using Rhino software and Griddle plug-in, and numerical simulation was performed using FLAC3D software.

6. A method for simulating a rock failure zone in a chamber excavation according to claim 1, characterized in that: In the process of assigning values ​​to different zones with different degrees of damage, different regional units are assigned different rock parameters, and units in the same region are assigned the same rock parameters, which include elastic modulus, cohesion, Poisson's ratio and internal friction angle.

7. The method for simulating the surrounding rock failure zone of a chamber excavation according to claim 1, characterized in that: The degree of surrounding rock failure is determined based on the plastic shear strain and the ultimate plastic shear strain.

8. A device for simulating the surrounding rock damage zone of a chamber excavation. Establishing units for building an initial model of the underground chamber; The first simulation unit is used to simulate the excavation process of the underground chamber without setting any support measures using the initial model of the underground chamber, obtain the range of the plastic zone, and extract the principal stress information of the unit corresponding to the failure zone; A calculation unit, used to calculate the degree of surrounding rock damage based on the surrounding rock stress state; an acquiring unit, configured to partition the damaged area according to the degree of damage of the surrounding rock to acquire refined partition information, wherein the refined partition information includes different partition information of different degrees of damage; The second acquisition unit is used to obtain rock mechanical parameters related to the residual strength of the surrounding rock at different damage degrees based on triaxial compression tests; an assignment unit, configured to assign values ​​to different partitions with different degrees of damage according to rock mechanics parameters related to the residual strength; The second simulation unit is used to re-perform the excavation numerical simulation to obtain the new plastic zone range and principal stress distribution; The iterative unit is used to repeat the steps from the acquisition unit to the second simulation unit until the partition assignment of the surrounding rock near the cavern is completed, so as to complete the final partition assignment and refined simulation.

9. An electronic device comprising: A memory and a processor, characterized in that the processor is used to implement the steps of the method for simulating the surrounding rock damage zone of chamber excavation as described in any one of claims 1 to 7 when executing the computer program stored in the memory.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method for simulating the surrounding rock damage zone of chamber excavation as described in any one of claims 1 to 7 are implemented.

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