Waste roadway grouting reconstruction compressed air energy storage library surrounding rock stability simulation method and system

Abstract

The present application relates to compressed air energy storage technology field, specifically to the abandoned roadway grouting reconstruction compressed air energy storage library surrounding rock stability simulation method and system, determine the initial geomechanics condition, determine the geological strength index value of the damage zone, the damage zone and the disturbance zone around the compressed air energy storage chamber;Call simulation software, use the material properties of different partitions, build the three-dimensional entity model of the surrounding rock of the abandoned roadway containing random cracks, and simulate the grouting diffusion range of the obtained entity model, import the obtained simulation results into the three-dimensional modeling software, obtain the gas storage model containing grid lines and import it into the three-dimensional numerical analysis program;Call the grouting reinforced fractured rock creep damage model under the disturbance of cyclic compression-storage-decompression, and embed it into the three-dimensional numerical analysis program;Based on the three-dimensional numerical analysis program, the stress field and deformation field evolution law of the compressed air energy storage gas storage library of the abandoned roadway after grouting reinforcement during the service period are numerically simulated and analyzed under the influence of different factors.

Description

Technical Field

[0001] This invention relates to the field of compressed air energy storage technology, specifically to a method and system for simulating the surrounding rock stability of a compressed air energy storage facility converted from grouting in abandoned roadways. Background Technology

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

[0003] Compressed air energy storage is a peak-shaving technology to cope with power grid fluctuations. It uses compressed air as a carrier, storing excess electricity in a gas storage tank during off-peak hours, and releasing the air during peak hours to mix with fuel and drive a gas turbine to generate electricity. The entire process includes compression, storage, and release stages, and can be cyclically charged and released to balance power supply and demand.

[0004] Gas storage facilities are an important component of compressed gas energy storage technology, and they generally require a large amount of surface space. However, the underground spaces and facilities left behind by some decommissioned or abandoned mines have enormous potential for resource recycling. Gas storage facilities can be built using underground spaces such as abandoned mine tunnels, which can reduce costs in terms of raw materials and land use. However, these abandoned tunnels have undergone long-term use, and their support structures are damaged. The stability and bearing capacity of the surrounding rock may not meet the requirements for gas storage.

[0005] To address this issue, grouting reinforcement is generally used to improve the strength of the support structure in abandoned mines. However, existing technologies require the introduction of more damage parameters and damage evolution models when performing numerical simulations of grouting reinforcement on gas storage facilities converted from abandoned roadways. This significantly increases the complexity of the model, and therefore, the initial damage to the surrounding rock is usually not considered. In the numerical simulation process, if the initial damage to the surrounding rock is not considered, it will affect the diffusion range of the grouting reinforcement, resulting in large errors in the numerical simulation results of stress field and displacement field when performing numerical simulations of gas storage facilities converted from abandoned roadways under the cyclic filling-storage-unloading state. Summary of the Invention

[0006] To address the technical problems mentioned above, this invention provides a method and system for simulating the surrounding rock stability of a compressed air energy storage facility by grouting an abandoned tunnel. This method closely reflects reality by generating random fissures around the chamber to simulate the actual properties of the surrounding rock. Numerical simulations of grouting reinforcement are then performed, and combined with the diffusion range of the grouting reinforcement, numerical simulations of the cyclic compression-storage-unloading state are conducted. Finally, the stress and deformation fields under the cyclic filling-storage-unloading state are analyzed to meet the requirements of compressed air energy storage.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] The first aspect of this invention provides a method for simulating the surrounding rock stability of a compressed air energy storage facility converted from an abandoned roadway through grouting, comprising the following steps:

[0009] Determine the initial geomechanical conditions and the geological strength index values ​​of the damaged, disturbed, and disrupted zones surrounding the compressed gas storage chamber;

[0010] Using simulation software and the material properties of different zones, a three-dimensional solid model of the surrounding rock of an abandoned roadway with random cracks was constructed. The grouting diffusion range of the obtained solid model was simulated, and the simulation results were imported into the three-dimensional modeling software to obtain a gas storage tank model with grid lines, which was then imported into the three-dimensional numerical analysis program.

[0011] The creep damage model of fractured rock reinforced by grouting under cyclic pressure-storage-unloading disturbance was called and embedded into a three-dimensional numerical analysis program. Based on the three-dimensional numerical analysis program, the evolution law of surrounding rock stress field and deformation field during the service of compressed air storage tank converted from abandoned roadway after grouting reinforcement was numerically simulated and analyzed under the influence of different factors.

[0012] As a further implementation method, the geological strength index values ​​of the damaged zone, the damaged zone and the disturbed zone around the compressed gas energy storage chamber are determined. Specifically, the block volume and joint condition factor are calculated by sampling the rock mass in each zone and obtaining the joint spacing of the samples and the angle between the joint groups. The geological strength index values ​​of the corresponding zone of each sample are determined by looking up the table.

[0013] As a further implementation method, simulation software is called to construct a three-dimensional solid model of the surrounding rock of the abandoned roadway containing random cracks by utilizing the material properties of different zones. Specifically, the "Discrete Crack Network - 3D" plugin in the simulation software is called to define the crack size, direction and attribute parameters of different regions in the failure zone, damage zone and disturbance zone, and generate a three-dimensional solid model of the surrounding rock of the abandoned roadway containing random cracks.

[0014] As a further implementation method, the grouting diffusion range is simulated on the obtained solid model. Specifically, the Darcy's law interface in the porous medium and groundwater flow sub-module of the fluid flow module in the simulation software is called to define different parameters for the failure zone, damage zone, disturbance zone and external surrounding rock. Numerical simulation of the grouting diffusion range is then performed on the three-dimensional solid model of the surrounding rock of the abandoned roadway containing random cracks.

[0015] As a further implementation, during the numerical simulation of the grouting diffusion range, the model is meshed according to the requirements of the Darcy's law interface, and the finite element method is used to transform the continuous physical field problem into a discrete system of algebraic equations. The numerical simulation results are obtained by discretizing and solving the Darcy's equations.

[0016] As a further implementation method, a creep damage model for grouting-reinforced fractured rock under cyclic pressure-storage-unloading disturbance is established. Based on experimental results and the principle of stress dissipation, a nonlinear sticky pot mechanical element is used to replace the Newton sticky pot in the Burgers creep model, and a nonlinear viscoplastic damage element is used to control the presence or absence of the unstable creep stage, describing the deformation characteristics of the unstable creep stage.

[0017] As a further implementation method, in the three-dimensional numerical analysis program, the Hoek-Brown constitutive model is selected to describe the mechanical behavior of grouting-reinforced fractured rock. By writing the corresponding Fish function, the calculation logic of the creep damage model of grouting-reinforced fractured rock under cyclic pressure-storage-unloading disturbance is determined. The written Fish function is embedded into the gas storage model with grid lines, and the model is verified and calibrated by comparison with experimental data or actual engineering cases.

[0018] A second aspect of the present invention provides a surrounding rock stability simulation system for grouting and retrofitting compressed air energy storage in abandoned roadways, comprising:

[0019] The initial conditions module is configured to: determine the initial geomechanical conditions and determine the geological strength index values ​​of the damaged zone, the disturbed zone and the fault zone around the compressed gas storage chamber;

[0020] The grouting diffusion simulation module is configured to: call simulation software, utilize the material properties of different zones to construct a three-dimensional solid model of the surrounding rock of an abandoned roadway containing random cracks, simulate the grouting diffusion range of the obtained solid model, import the simulation results into the three-dimensional modeling software, obtain a gas storage tank model with grid lines, and import it into the three-dimensional numerical analysis program.

[0021] The numerical simulation module is configured to: call the creep damage model of grouting-reinforced fractured rock under cyclic pressure-storage-unloading disturbance and embed it into the three-dimensional numerical analysis program; based on the three-dimensional numerical analysis program, perform numerical simulation analysis on the evolution of the stress field and deformation field of the surrounding rock during the service of the compressed air storage tank after grouting reinforcement and the transformation of abandoned roadways under the influence of different factors.

[0022] A third aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps in the above-described method for simulating the surrounding rock stability of a compressed air energy storage tank through grouting in an abandoned roadway.

[0023] A fourth aspect of the present invention provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps in the above-described method for simulating the surrounding rock stability of a compressed air energy storage tank by grouting in an abandoned roadway.

[0024] Compared with existing technologies, one or more of the above technical solutions have the following beneficial effects:

[0025] The simulation considered the initial damage to the surrounding rock. By dividing the abandoned roadway's surrounding rock into zones and generating different fractures based on the required properties of the surrounding rock in different areas, grouting simulations were performed on roadways containing fractures to obtain the effective reinforcement range contour map. By considering initial damage, grouting parameters, such as grouting pressure and volume, can be optimized according to the actual state of the surrounding rock. This optimization not only improves the grouting effect but also reduces material waste and construction risks caused by unreasonable parameters. This refined simulation makes grouting reinforcement design more targeted, effectively improving grouting results and reducing the risk of reinforcement failure due to unclear fracture distribution. Traditional grouting reinforcement technology in abandoned roadway reconstruction often requires numerous grouting tests and repeated construction due to a lack of accurate assessment of the initial state of the surrounding rock. This scheme determines the effective reinforcement range through simulation, avoiding unnecessary grouting areas and thus reducing material and labor costs. The simulation also included a thermo-coupling numerical model of the surrounding rock deterioration of a compressed air storage (CAS) abandoned roadway after grouting reinforcement, followed by grouting reconstruction under different influencing factors. Attached Figure Description

[0026] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0027] Figure 1 This is a flowchart of a method for simulating the surrounding rock stability of a compressed air energy storage facility through grouting in an abandoned roadway, provided by one or more embodiments of the present invention.

[0028] Figure 2 This is a GSI chart provided in one or more embodiments of the present invention;

[0029] Figure 3 This is a diffusion range diagram of surrounding rock grouting reinforcement simulated using COMSOL, provided by one or more embodiments of the present invention;

[0030] Figure 4 This is a diffusion profile of surrounding rock grouting reinforcement simulated using COMSOL, provided by one or more embodiments of the present invention;

[0031] Figure 5 This is a model diagram of a compressed gas storage tank constructed using Rhino 3DNURBS, provided in one or more embodiments of the present invention.

[0032] Figure 6This is a diagram showing the results of one and 100 vertical stresses of a compressed air energy storage tank under the same burial depth conditions, simulated using FLAC3D, provided by one or more embodiments of the present invention.

[0033] Figure 7 This is a diagram showing the results of one vertical stress and 100 vertical displacements of a compressed gas storage tank simulated using FLAC3D under the same burial depth conditions, provided by one or more embodiments of the present invention.

[0034] Figure 8 This is a diagram showing the results of one and 100 horizontal stresses of a compressed gas storage tank under the same burial depth conditions, simulated using FLAC3D, provided by one or more embodiments of the present invention.

[0035] Figure 9 This is a diagram showing the results of one horizontal displacement and 100 horizontal displacements of a compressed gas storage tank simulated using FLAC3D under the same burial depth conditions, provided by one or more embodiments of the present invention.

[0036] Figure 10 The figures provided by one or more embodiments of the present invention are vertical stress results of a compressed gas storage tank under gas storage conditions at burial depths of 100m and 200m, respectively, using FLAC3D simulation.

[0037] Figure 11 The figures provided by one or more embodiments of the present invention are vertical displacement results of a compressed gas storage tank under gas storage conditions at burial depths of 100m and 200m, respectively, using FLAC3D simulation.

[0038] Figure 12 The diagram shows the horizontal stress results of a compressed gas storage tank under gas storage conditions at burial depths of 100m and 200m, respectively, as simulated using FLAC3D in one or more embodiments of the present invention.

[0039] Figure 13 These are diagrams showing the horizontal displacement results of a compressed gas storage tank under gas storage conditions at burial depths of 100m and 200m, respectively, as simulated using FLAC3D in one or more embodiments of the present invention. Detailed Implementation

[0040] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0041] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0042] Terminology Explanation:

[0043] Abandoned tunnels are tunnels that were once used for passage, mining, or other purposes but are now abandoned and no longer in use. These tunnels may be located underground in cities, deep in mines, or elsewhere, abandoned for various reasons, and may become dangerous due to long-term lack of maintenance.

[0044] The following embodiments provide a method and system for simulating the surrounding rock stability of a compressed air energy storage facility by grouting an abandoned tunnel. Random fractures are generated around the chamber to simulate the properties of the surrounding rock under real conditions. Numerical simulation of grouting reinforcement is then performed, and numerical simulation of the cyclic compression-storage-unloading state is conducted in conjunction with the diffusion range of the grouting reinforcement. Finally, the stress and deformation fields under the cyclic filling-storage-unloading state are analyzed to meet the requirements of compressed air energy storage.

[0045] Example 1:

[0046] like Figure 1 As shown, the method for simulating the surrounding rock stability of a compressed air energy storage facility converted from an abandoned roadway by grouting includes the following steps:

[0047] Step 1: Determine the initial geomechanical conditions, that is, determine the GSI values ​​(geological strength index, a parameter used to measure the strength and stability of geological rocks) of the damaged zone, damaged zone and disturbed zone around the compressed gas storage chamber.

[0048] In this embodiment, typical rock masses from each zone are taken out for on-site measurement to obtain various data, and the block volume (V) is calculated using the following formulas (1) and (2). b ) and joint condition factor (J c ), where s i and r i These are the joint spacing and the angle between joint groups, respectively, obtained through field measurements. J c J w and J A These are large-scale fluctuations, small-scale smoothness, and joint alteration factors, respectively, and their specific data were obtained through field measurements. Figure 2 For the GSI table, calculate the block volume (V) b ) and joint condition factor (J c Substitute this into the GSI chart and find the value that corresponds to the calculated block volume (V). b The value corresponding to ) is then found, and the joint condition factor (J) is also found. c The corresponding value. The intersection of these two values ​​is the GSI value of the rock mass.

[0049]

[0050] Step 2: Using the 3D discrete fracture network plugin in simulation software (such as COMSOL), generate a 3D solid model of the surrounding rock of the abandoned roadway containing random fractures, targeting the damaged area, disturbed area, and disrupted area in the gas storage facility.

[0051] To simulate the actual conditions of the surrounding rock around the chamber, the surrounding rock was divided into zones. Different material properties were defined for each zone, and random fractures that closely resembled actual working conditions were generated. The location of the fractures followed a uniform random distribution function, their size followed a power-law distribution function, and their direction followed a Fisher distribution. By adjusting the parameters of the power-law distribution function, the distribution of fracture size was changed, thereby affecting the fracture density.

[0052] In the COMSOL main screen toolbar, select the display options in the selection command to create geometric entities for the damaged zone, the damaged area, and the disturbed zone around the chamber. This allows you to select zones in the discrete fracture plugin to generate fractures with different parameters. Add the "Discrete Fracture Network - 3D" plugin for groundwater flow to the plugin library in the developer tools options bar. Return to the model developer and open the "Discrete Fracture Network - 3D" settings window under global definitions. According to the previously set display options for the damaged zone, the damaged area, and the disturbed zone, define the fracture size (minimum axis length, maximum axis length, power law), direction (strike, dip angle, dispersion coefficient), and attribute (porosity, roughness coefficient, pore size distribution, size factor) parameters for different regions.

[0053] This plugin can generate a fracture network based on actual geological conditions, setting parameters such as fracture location, size, and orientation according to a certain random distribution law. For example, fracture location follows a uniform random distribution function, size follows a power-law distribution function, and orientation follows a Fisher distribution. This randomness can effectively simulate the disordered distribution characteristics of fractures in nature, making the generated fracture network closer to actual geological conditions. Secondly, this plugin is suitable for creating discrete fracture networks in realistic geometries and can handle complex geometries such as reservoirs and rock strata. This means that when simulating working conditions with complex geometries, the plugin can accurately generate fractures within these geometries, ensuring the accuracy of the simulation results.

[0054] Step 3: Using simulation software (such as COMSOL), the Darcy's Law interface in the porous media and groundwater flow sub-module of the fluid flow module is used to numerically simulate the grouting diffusion range of the model with generated three-dimensional fractures.

[0055] Darcy's law describes the flow of fluid through gaps in a perfectly saturated porous medium. This motion is primarily driven by the pressure gradient, and the momentum transfer caused by the fluid's shear stress is negligible. Its mathematical expression is: Where u is the Darcy velocity, k is the permeability, and u is the dynamic viscosity of the fluid. It is the pressure gradient. The software analyzes the pressure and velocity distribution obtained from the simulation to determine the diffusion path and range of the fluid in the porous medium.

[0056] Different parameters are defined for the failure zone, damage zone, disturbed zone, and external surrounding rock in the software. The permeability of the failure zone is 1×10⁻⁶. -12 m 2 The porosity is 0.464; the permeability of the damaged zone is 1×10⁻⁶. -14 m 2 The porosity is 0.1; the permeability of the disturbed zone is 1×10⁻⁶. -16 m 2 The porosity is 0.02, and the external surrounding rock is defined using granite from the material library. The density of the slurry material is 1700 kg / m³, and the dynamic viscosity is 1 × 10⁻⁶. -3 Pa.s.

[0057] To account for the influence of gravity on the pressure gradient during slurry diffusion, the "Include Gravity" checkbox is selected in the Darcy's Law settings window to consider the gravitational effect of the slurry during injection. Since the gravitational potential energy of the fluid is height-dependent, the bottom of the gas storage tank model is defined as the gravity reference position to make the calculation of gravitational potential energy more intuitive. Gravity changes the flow direction and velocity of the slurry, which is crucial for accurately simulating the diffusion range of the slurry under complex geological conditions. Considering that the liquid is mainly driven by the pressure gradient in Darcy's Law, the inlet is defined as the grouting channel, and the outlet is all external boundaries in the software. To simplify the boundary condition settings of the model, the outlet pressure is defined as 0 MPa, and the inlet pressure is defined as 4 MPa.

[0058] Meshing was performed using a physics-controlled network. In this embodiment, COMSOL software automatically meshed the model according to the selected Darcy's Law interface. The mesh cell size was set to standard, and the complete mesh contained 169,892 domain elements, 24,310 boundary elements, and 6,221 edge elements. In COMSOL, the meshing was controlled by the physics field, and the software automatically meshed the model according to the requirements of the Darcy's Law interface. After meshing, the Darcy equations were discretized and solved using the finite element method. The finite element method transforms continuous physics problems into discrete algebraic equations, allowing complex fluid flow problems to be solved on a computer. To obtain a range within which slurry diffusion reaches stability, steady-state calculations were considered. Figure 3 Diagram showing the diffusion range of grouting reinforcement in compressed air energy storage tunnels. Figure 4 The diagram shown is a cross-sectional view of the diffusion range along the y-axis.

[0059] Step 4: In the Comsol simulation results in Step 3, create five sets of cross-sections with the same spacing along the depth direction of the slurry diffusion range. Then, sketch the contour of each cross-section and import the contour data into 3D modeling software (such as Rhino 3DNURBS) for lofting to form a 3D solid model. Figure 5 This is a model of a gas storage facility built in Rhino.

[0060] Step 5: Use the Kubrix plugin in the 3D modeling software Rhino to import the constructed and meshed gas storage model into a 3D numerical analysis program (such as FLAC3D).

[0061] Step Six: Embed a creep damage model for grout-reinforced fractured rock under cyclic pressure-storage-unloading disturbance in FLAC3D. This model is based on the test results of the long-term bearing characteristics of grout-reinforced fractured rock under cyclic pressure-storage-unloading disturbance, analyzing the stress and deformation mechanism of grout-reinforced fractured rock under cyclic pressure-storage-unloading disturbance. During fatigue, the deformation of the grout-reinforced fractured rock gradually accumulates. When the deformation increases to a certain extent, cracks will appear in the grout-reinforced fractured rock. Therefore, based on the stress dissipation principle, a nonlinear sticky pot mechanical element (DS sticky pot) is introduced to replace the Newton sticky pot in the Burgers creep model. At the same time, a new nonlinear viscoplastic damage element (stress threshold switching element and strain-triggered viscous element in parallel) is introduced to control the presence or absence of the unstable creep stage and describe the deformation characteristics of the unstable creep stage. Thus, a creep damage model for grout-reinforced fractured rock under cyclic pressure-storage-unloading disturbance is established, and damage variables are established according to Kachanov creep damage theory, providing a basis for the numerical simulation test in this embodiment.

[0062] In FLAC3D, the Hoek-Brown constitutive model is first selected to describe the mechanical behavior of grout-reinforced fractured rock. A corresponding Fish function is written to implement the computational logic of the creep damage model for grout-reinforced fractured rock under cyclic pressure-storage-unloading disturbance. The written Fish function is embedded into the FLAC3D model, and the model is validated and calibrated by comparison with experimental data or actual engineering cases. Model parameters are adjusted to ensure that the calculation results match the actual situation as closely as possible, thus ensuring the model's accuracy and reliability. This model can comprehensively consider the stress and displacement characteristics of rock under cyclic pressure-storage-unloading disturbance, more accurately describe the long-term deformation and strength decay of rock, and provide a more reliable theoretical basis for rock mechanics analysis.

[0063] Step 7: Simulate the evolution of the stress field and deformation field of the surrounding rock under the influence of different factors in FLAC3D.

[0064] This embodiment addresses the stress characteristics of compressed air energy storage chambers. Based on thermo-mechanical coupling theory, it employs a thermo-mechanical coupling numerical simulation analysis method to explore the spatial distribution and variation of structural stress and deformation of the surrounding rock and lining under power plant operating conditions. The stress and deformation fields of the gas storage chamber are simulated under different conditions, including 1 and 100 cycles of compression-storage-unloading, and at burial depths of 100m and 200m.

[0065] Step 8: Analyze the numerical simulation results.

[0066] The simulation results of FLAC3D are analyzed. Figure 6 The diagram shows the vertical stress after one cycle of pressurization-storage-deflation and after 100 cycles of pressurization-storage-deflation upon completion of inflation. Figure 7 This diagram shows the results of one vertical stress and 100 vertical displacements in a compressed air energy storage facility under the same burial depth conditions. Figure 6 It can be seen that the stress distribution exhibits a clear regularity: the stress value is higher around the gas storage facility, and gradually decreases with increasing distance from the storage wall. This is due to the pressure of the stored gas inside the facility, causing the storage wall to bear significant stress. Comparison shows that after multiple cycles, the stress value near the storage wall is somewhat released, possibly due to plastic deformation and stress redistribution in the rock mass during the repeated cycles. Figure 7 It can be seen that after 100 cycles of inflation and deflation, the deformation and deformation range of the surrounding rock at the bottom of the chamber are greater than those after one cycle of inflation and deflation.

[0067] Figure 8 and Figure 9 The figures show the results of the first and 100th horizontal stress cycles and the horizontal displacement of a compressed air energy storage facility under the same burial depth. Figure 8 It can be seen that, under the gas storage condition after one cycle of inflation and deflation, the pressure change inside the chamber exerts a significant pressure effect on the chamber wall. In areas far from the chamber wall, the horizontal stress gradually transitions from compressive to tensile stress, and the stress value gradually decreases, showing the characteristic of stress diffusion and attenuation from the chamber wall to distant locations. After multiple cycles, the pressure value near the chamber wall increases, which may be due to plastic deformation and stress redistribution in the rock mass during the multiple cycles. Figure 8 The horizontal displacement diagram also shows that the strain of the horizontal displacement decreases with increasing distance from the surrounding chamber, but the horizontal displacement of the surrounding rock after one inflation and deflation cycle is smaller than that after 100 cycles.

[0068] Figure 10 and Figure 11The figures show the vertical stress and displacement results of a compressed air energy storage facility at burial depths of 100m and 200m, respectively, under compressed air storage conditions. Figure 10 and Figure 11 It can be seen that, when the chamber is buried at a depth of 100m, the surrounding rock experiences less vertical compressive stress in the upper part compared to the chamber at a depth of 200m, while the difference in vertical compressive stress in the lower part is not significant. At a depth of 100m, the upper part of the surrounding rock in the gas storage chamber mainly shifts upwards, while the lower part mainly shifts downwards. This is likely because the gas in the storage chamber exerts compressive stress on the surrounding rock, causing it to shift outwards. At a depth of 200m, the upper part of the surrounding rock in the gas storage chamber mainly shifts downwards, while the lower part mainly shifts upwards. The influence decreases with increasing distance from the gas storage chamber.

[0069] Figure 12 and Figure 13 The figures show the horizontal stress and displacement results of a compressed air storage (CASS) gas reservoir at depths of 100m and 200m, respectively, under gas storage conditions. It can be seen that, under gas storage conditions, the shallower reservoir experiences greater horizontal stress on the surrounding rock above compared to the deeper reservoir, but the stress distribution pattern remains the same: both the upper and lower surrounding rock layers experience tensile stress, while the left and right sides experience compressive stress. The horizontal displacement of the 200m reservoir is smaller than that at 100m, but the distribution pattern remains the same, and the horizontal displacement decreases with increasing distance from the reservoir.

[0070] By dividing the surrounding rock of abandoned roadways into zones and generating different fissures according to the property requirements of the surrounding rock in different areas of the abandoned roadways, and by grouting simulation of roadways containing fissures to obtain the outline of their effective reinforcement range, costs are reduced and efficiency is improved.

[0071] Numerical simulation of the thermal coupling of the surrounding rock deterioration of the compressed gas storage reservoir under different influences was conducted by grouting reinforcement of abandoned roadways and then grouting modification of abandoned roadways.

[0072] The evolution of the stress field and deformation field of the surrounding rock, as well as the law and mechanism of surrounding rock damage and deterioration, were simulated under cyclic compression-storage-unloading disturbances of 1 and 100 times and burial depths of 100m and 200m.

[0073] Example 2:

[0074] The surrounding rock stability simulation system for grouting and converting abandoned roadways into compressed air energy storage facilities includes:

[0075] The initial conditions module is configured to: determine the initial geomechanical conditions and determine the geological strength index values ​​of the damaged zone, the disturbed zone and the fault zone around the compressed gas storage chamber;

[0076] The grouting diffusion simulation module is configured to: call simulation software, utilize the material properties of different zones to construct a three-dimensional solid model of the surrounding rock of an abandoned roadway containing random cracks, simulate the grouting diffusion range of the obtained solid model, import the simulation results into the three-dimensional modeling software, obtain a gas storage tank model with grid lines, and import it into the three-dimensional numerical analysis program.

[0077] The numerical simulation module is configured to: call the creep damage model of grouting-reinforced fractured rock under cyclic pressure-storage-unloading disturbance and embed it into the three-dimensional numerical analysis program; based on the three-dimensional numerical analysis program, perform numerical simulation analysis on the evolution of the stress field and deformation field of the surrounding rock during the service of the compressed air storage tank after grouting reinforcement and the transformation of abandoned roadways under the influence of different factors.

[0078] The simulation considered the initial damage to the surrounding rock. By dividing the abandoned roadway's surrounding rock into zones and generating different fractures according to the property requirements of the surrounding rock in different areas of the abandoned roadway, grouting simulation was performed on the roadway containing fractures to obtain the outline of its effective reinforcement range, reducing costs and improving efficiency. A thermo-mechanical coupled numerical simulation was conducted on the deterioration of the surrounding rock of the abandoned compressed gas storage (CGS) energy storage tank under different influencing factors after grouting reinforcement.

[0079] Example 3:

[0080] A computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps in the above-mentioned method for simulating the surrounding rock stability of a compressed air energy storage system for grouting and converting abandoned roadways.

[0081] Example 4:

[0082] A computer device includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, it implements the steps in the above-mentioned method for simulating the surrounding rock stability of a compressed air energy storage tank through grouting in an abandoned roadway.

[0083] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for simulating the surrounding rock stability of a compressed air energy storage facility converted from an abandoned roadway by grouting, characterized in that, Includes the following steps: Determine the initial geomechanical conditions and the geological strength index values ​​of the damaged, disturbed, and disrupted zones surrounding the compressed gas storage chamber; Using simulation software and the material properties of different zones, a three-dimensional solid model of the surrounding rock of an abandoned roadway containing random fractures was constructed. The grouting diffusion range of the obtained solid model was simulated, and the simulation results were imported into a three-dimensional modeling software to obtain a gas storage tank model with grid lines, which was then imported into a three-dimensional numerical analysis program. Specifically, the simulation software was used to construct a three-dimensional solid model of the surrounding rock of an abandoned roadway containing random fractures by using the material properties of different zones. The "Discrete Fracture Network - 3D" plugin in the simulation software was called to define the fracture size, direction, and attribute parameters of different regions in the failure zone, damage zone, and disturbance zone, thereby generating a three-dimensional solid model of the surrounding rock of an abandoned roadway containing random fractures. The creep damage model of fractured rock reinforced by grouting under cyclic pressure-storage-unloading gas disturbance was called and embedded into the three-dimensional numerical analysis program; Based on a three-dimensional numerical analysis program, this study numerically simulates and analyzes the evolution of the surrounding rock stress field and deformation field during service of a compressed air storage facility that has undergone grouting reinforcement and has been converted from an abandoned roadway, under the influence of different factors. A creep damage model for grouting-reinforced fractured rock under cyclic pressure-storage-unloading disturbance is established. Based on experimental results and the principle of stress dissipation, a nonlinear sticky pot mechanical element is used to replace the Newtonian sticky pot in the Burgers creep model, and a nonlinear viscoplastic damage element is used to control the presence or absence of the unstable creep stage, describing the deformation characteristics of the unstable creep stage. In the three-dimensional numerical analysis program, the Hoek-Brown constitutive model is selected to describe the mechanical behavior of grouting-reinforced fractured rock. The calculation logic of the creep damage model under cyclic pressure-storage-unloading disturbance is determined by writing the corresponding Fish function. The Fish function is embedded into the gas storage model containing grid lines, and the model is verified and calibrated by comparison with experimental data or actual engineering cases.

2. The method for simulating the surrounding rock stability of a compressed air energy storage facility converted from an abandoned roadway by grouting, as described in claim 1, is characterized in that... The geological strength index values ​​of the damaged zone, the damaged zone, and the disturbed zone around the compressed gas energy storage chamber are determined by: sampling the rock mass in each zone and obtaining the joint spacing of the samples and the angle between the joint groups, calculating the block volume and joint condition factor, and determining the geological strength index value of the zone corresponding to each sample by looking up a table.

3. The method for simulating the surrounding rock stability of a compressed air energy storage facility converted from an abandoned roadway by grouting, as described in claim 1, is characterized in that... The obtained solid model was used to simulate the grouting diffusion range. Specifically, the Darcy's law interface in the porous media and groundwater flow sub-module of the fluid flow module in the simulation software was called to define different parameters for the failure zone, damage zone, disturbance zone and external surrounding rock. Numerical simulation of the grouting diffusion range was performed on the three-dimensional solid model of the surrounding rock of the abandoned roadway containing random cracks.

4. The method for simulating the surrounding rock stability of a compressed air energy storage facility converted from an abandoned roadway by grouting, as described in claim 1, is characterized in that... During the numerical simulation of the grouting diffusion range, the model was meshed according to the requirements of the Darcy's law interface, and the finite element method was used to transform the continuous physical field problem into a discrete algebraic equation system. The numerical simulation results were obtained by discretizing and solving the Darcy's equation.

5. A system for simulating the surrounding rock stability of a compressed air energy storage facility converted from an abandoned roadway by grouting, characterized in that: include: The initial conditions module is configured to: determine the initial geomechanical conditions and determine the geological strength index values ​​of the damaged zone, the disturbed zone and the fault zone around the compressed gas storage chamber; The grouting diffusion simulation module is configured to: call simulation software, utilize the material properties of different zones to construct a three-dimensional solid model of the surrounding rock of an abandoned roadway containing random fractures, and simulate the grouting diffusion range of the obtained solid model. The simulation results are then imported into a three-dimensional modeling software to obtain a gas storage tank model with grid lines, which is then imported into a three-dimensional numerical analysis program. Specifically, the module calls the simulation software to construct a three-dimensional solid model of the surrounding rock of an abandoned roadway containing random fractures, utilizing the material properties of different zones. This involves calling the "Discrete Fracture Network - 3D" plugin in the simulation software, defining the fracture size, direction, and attribute parameters of different regions in the failure zone, damage zone, and disturbance zone, and generating a three-dimensional solid model of the surrounding rock of an abandoned roadway containing random fractures. The numerical simulation module is configured to call the creep damage model of grouting reinforced fractured rock under cyclic pressure-storage-unloading gas disturbance and embed it into the three-dimensional numerical analysis program; Based on a three-dimensional numerical analysis program, this study numerically simulates and analyzes the evolution of the surrounding rock stress field and deformation field during service of a compressed air storage facility that has undergone grouting reinforcement and has been converted from an abandoned roadway, under the influence of different factors. A creep damage model for grouting-reinforced fractured rock under cyclic pressure-storage-unloading disturbance is established. Based on experimental results and the principle of stress dissipation, a nonlinear sticky pot mechanical element is used to replace the Newtonian sticky pot in the Burgers creep model, and a nonlinear viscoplastic damage element is used to control the presence or absence of the unstable creep stage, describing the deformation characteristics of the unstable creep stage. In the three-dimensional numerical analysis program, the Hoek-Brown constitutive model is selected to describe the mechanical behavior of grouting-reinforced fractured rock. The calculation logic of the creep damage model under cyclic pressure-storage-unloading disturbance is determined by writing the corresponding Fish function. The Fish function is embedded into the gas storage model containing grid lines, and the model is verified and calibrated by comparison with experimental data or actual engineering cases.

6. A computer-readable storage medium, characterized in that, It stores a computer program that, when executed by a processor, implements the steps in the method for simulating the surrounding rock stability of a compressed air energy storage tank by grouting an abandoned roadway as described in any one of claims 1-4.

7. A computer device, characterized in that, It includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, it implements the steps in the method for simulating the surrounding rock stability of a compressed air energy storage tank by grouting an abandoned roadway as described in any one of claims 1-4.

Images