Method and system for determining pressure interval in air energy storage underground lining chamber

Abstract

This application belongs to the field of compressed air energy storage technology, specifically disclosing a method and system for determining the internal pressure range of an underground lining chamber for compressed air energy storage. The method includes: obtaining the total stress distribution of the inner wall of the lining chamber's surrounding rock under the combined action of far-field vertical geostress and internal pressure; obtaining the functional relationship between the maximum and minimum principal stresses at the most critical point and the internal pressure, geostress, and lateral stress coefficients; performing coordinate transformation on the maximum and minimum principal stresses to simplify the Hoek-Brown criterion to a linear relationship on the scaled principal stress plane; and, for high and low internal pressure conditions, calculating the internal pressure at which the surrounding rock just enters a plastic state based on the functional relationship and the simplified Hoek-Brown criterion, as the upper and lower limits of the internal pressure. This application can accurately determine the internal pressure range of an underground lining chamber for compressed air energy storage, ensuring that the surrounding rock of the chamber maintains an elastic state during the inflation and deflation cycles, avoiding accumulated plastic damage, and thus extending the facility's lifespan.

Description

Technical Field

[0001] This application belongs to the field of compressed air energy storage technology, and more specifically, relates to a method and system for determining the internal pressure zone of an underground lining tunnel for air energy storage. Background Technology

[0002] Compressed air energy storage (CAES) is a promising large-scale energy storage technology that can effectively address the intermittency of renewable energy sources. CAES systems typically use underground salt caverns or lined chambers as gas storage facilities. Among these, lined chambers have attracted widespread attention in recent years due to their high site selection flexibility and adaptability. However, during operation, frequent inflation and deflation cycles in CAES systems can cause the surrounding rock mass to enter a plastic state, resulting in cumulative plastic damage and shortening the facility's lifespan. Therefore, determining the internal pressure range of the chamber to ensure the rock mass operates in an elastic state is a critical issue in CAES system design.

[0003] In the existing technology, the method for determining the pressure range inside the tunnel is mainly based on the Mohr-Coulomb criterion. This criterion describes the failure behavior of rock mass through a linear approximation, which is difficult to accurately reflect the failure characteristics of nonlinear rock mass.

[0004] Therefore, accurately determining the internal pressure range of the underground lining chamber for compressed air energy storage to ensure that the surrounding rock of the chamber remains elastic during the air filling and releasing cycle is an urgent problem to be solved. Summary of the Invention

[0005] In view of the deficiencies of the prior art, the purpose of this application is to provide a method and system for determining the internal pressure range of an underground lining chamber for compressed air energy storage. This method can accurately determine the internal pressure range of the underground lining chamber for compressed air energy storage, so as to ensure that the surrounding rock of the chamber maintains an elastic state during the inflation and deflation cycle, avoid the accumulation of plastic damage, and thus extend the service life of the facility.

[0006] To achieve the above objectives, in a first aspect, this application provides a method for determining the internal pressure zone of an underground lining tunnel for air energy storage, comprising the following steps: S10, obtain the total stress distribution of the inner wall of the lining chamber under the combined action of far-field vertical ground stress and internal pressure, thereby obtaining the functional relationship between the maximum principal stress and minimum principal stress at the most dangerous point and the internal pressure, ground stress and lateral stress coefficient; S20, by performing coordinate transformation on the maximum and minimum principal stresses, simplifies the Hoek-Brown criterion to a linear relationship on the scaling principal stress plane; S30, For high internal pressure conditions, based on the aforementioned functional relationship and the simplified Hoek-Brown criterion, the internal pressure when the surrounding rock just enters the plastic state is calculated as the upper limit of internal pressure; S40, For low internal pressure conditions, based on the aforementioned functional relationship and the simplified Hoek-Brown criterion, the internal pressure when the surrounding rock just enters the plastic state is calculated as the lower limit of internal pressure. S50, the safe operating internal pressure range of the lining chamber is determined by the upper limit and lower limit of the internal pressure.

[0007] As a further preferred embodiment, in step S10, the total stress distribution is obtained by superimposing the first stress field and the second stress field; The first stress field is: ;in, , , These are the radial normal stress, circumferential normal stress, and circumferential shear stress in the first stress field, respectively. The internal pressure; The second stress field is: ;in, , , These are the radial normal stress, circumferential normal stress, and circumferential shear stress in the second stress field, respectively. The radius of the gas storage facility; Radial distance; The lateral stress coefficient in the second stress field; The azimuth angle is in polar coordinates; , The far-field vertical ground stress; The total stress distribution is as follows: ;in, The radial stress in the total stress field; The circumferential stress in the total stress field; This represents the shear stress in the total stress field. denoted as the lateral stress coefficient in the total stress field.

[0008] As a further preferred option, the method also includes a Hoek-Brown criterion core parameter calculation step performed before step S20: based on the geological strength index GSI and the intact rock mass constant. The rock mass material constants are calculated using the following formula, along with the construction disturbance factor D. Rock mass constant and nonlinear parameters : .

[0009] As a further preferred embodiment, in step S20, the coordinate transformation adopts the following formula:

[0010] In the formula, S1 is the scaled maximum principal stress, and S3 is the scaled minimum principal stress. This is the maximum principal stress; It is the minimum principal stress; The uniaxial compressive strength of the intact rock mass; , These correspond to the rock mass material constant and rock mass constant in the Hoek-Brown criterion.

[0011] As a further preferred embodiment, in step S20, when the nonlinear parameter in the Hoek-Brown criterion... When the value is 0.5, the simplified linear relationship is expressed on the scaled principal stress plane as follows: S1=S3 0.5 +S3 In the formula, S1 is the scaled maximum principal stress, and S3 is the scaled minimum principal stress.

[0012] As a further preferred embodiment, in step S30, the upper limit of internal pressure is determined as follows: Under high internal pressure conditions, the most dangerous point on the scaling principal stress plane is located on the straight line S1=S3, and the intersection of this point and the simplified Hoek-Brown criterion curve is calculated to obtain the upper limit of scaling internal pressure. Then, the actual upper limit of internal pressure is obtained through inverse coordinate transformation. ,in , This corresponds to the rock mass material constant and rock mass constant in the Hoek-Brown criterion. It represents the uniaxial compressive strength of an intact rock mass.

[0013] As a further preferred embodiment, the upper limit of the scaling internal pressure... for:

[0014]

[0015] In the formula, The lateral stress coefficient in the total stress field; The far-field vertical ground stress is denoted as .

[0016] As a further preferred embodiment, in step S40, the lower limit of internal pressure is determined as follows: under low internal pressure conditions, the most critical point on the scaled principal stress plane is determined, and the intersection of this point and the simplified Hoek-Brown criterion curve is calculated to obtain the scaled lower limit of internal pressure. Then, the lower limit of the actual internal pressure is obtained through inverse coordinate transformation. ,in , This corresponds to the rock mass material constant and rock mass constant in the Hoek-Brown criterion. It represents the uniaxial compressive strength of an intact rock mass.

[0017] As a further preferred embodiment, the scaling internal pressure lower limit for:

[0018]

[0019] In the formula, The lateral stress coefficient in the total stress field; The far-field vertical ground stress is denoted as .

[0020] Secondly, this application provides a system for determining the internal pressure zone of an air-storage underground lining tunnel, used to implement the steps of the method for determining the internal pressure zone of an air-storage underground lining tunnel as described above, including: The stress distribution acquisition module is used to acquire the total stress distribution of the inner wall of the lining chamber surrounding rock under the combined action of far-field stress and internal pressure, thereby obtaining the functional relationship between the maximum and minimum principal stresses at the most dangerous point and the internal pressure, ground stress and lateral stress coefficient; The coordinate transformation module is used to perform coordinate transformation on the maximum principal stress and the minimum principal stress, simplifying the Hoek-Brown criterion into a linear relationship on the scaling principal stress plane. The internal pressure upper limit solution module is used to solve the internal pressure when the surrounding rock just enters the plastic state, based on the aforementioned functional relationship and the simplified Hoek-Brown criterion, for high internal pressure working conditions, as the internal pressure upper limit; The internal pressure lower limit solution module is used to solve the internal pressure when the surrounding rock just enters the plastic state, based on the aforementioned functional relationship and the simplified Hoek-Brown criterion, for low internal pressure working conditions, as the internal pressure lower limit. The safety range determination module is used to determine the safe operating internal pressure range of the lining chamber from the upper limit and the lower limit of the internal pressure.

[0021] The beneficial effects of this application are as follows: By deriving an analytical solution, this application can calculate the upper and lower limits of the LRC pressure in a lined rock tunnel based on rock mechanics parameters and engineering geological conditions. This ensures that the tunnel maintains an elastic state during the inflation and deflation cycles, avoiding cumulative plastic damage to the surrounding rock and effectively extending the service life of the compressed air energy storage facility. This application has the advantages of accurate calculation, high efficiency, and strong applicability, providing a scientific basis for the design and optimization of compressed air energy storage systems. Specifically: (1) This application derives an analytical solution based on the Hoek-Brown criterion, which more accurately characterizes the nonlinear failure characteristics of jointed rock masses compared with the linear approximation of the Mohr-Coulomb criterion. The error between the analytical solution and the numerical simulation results is less than 10%, and the calculation accuracy is high. (2) The analytical solution does not require complex iteration or numerical simulation. The internal pressure range can be obtained directly through formula calculation, which significantly improves the calculation efficiency and is suitable for rapid evaluation in the CAES engineering design stage. (3) The analytical solution has a wide range of applications, covering various hard rock masses with GSI=30-100 and different construction disturbance scenarios with disturbance factor D=0-1, and has strong engineering applicability. Attached Figure Description

[0022] Figure 1 This is a flowchart of the method for determining the internal pressure range provided in this application; Figure 2 This is a schematic diagram of the CAES system and the surrounding rock stress field provided in this application; wherein, (a) is the layout of the CAES system, (b) is the stress state of the surrounding rock in section A-A', (c) is the first stress field, and (d) is the second stress field. Figure 3 This is a diagram of the internal surface stress state provided in this application; Figure 4 This is the coordinate transformation derivation diagram under the Hoek-Brown criterion provided in this application; Figure 5 These are elastoplastic state diagrams under different internal pressures provided in the embodiments of this application. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0024] This application provides a method for determining the internal pressure range of an underground lined chamber for compressed air energy storage, based on the Hoek-Brown criterion and with simplified calculations. Based on the Hoek-Brown criterion, analytical solutions for determining the minimum and maximum internal pressures of the chamber are derived through geometric analysis and coordinate transformation. These analytical solutions consider the nonlinear failure characteristics of the rock mass and can more accurately reflect its mechanical behavior.

[0025] like Figure 1 As shown, the method for determining the internal pressure range of an underground lining tunnel for compressed air energy storage based on the Hoek-Brown criterion provided in this application includes: Step 1: Construct a surrounding rock mechanics model and simplify the stress analysis of the chamber.

[0026] Step 2: Solve the total stress field of the surrounding rock based on the principle of stress superposition.

[0027] Step 3: Solve for the upper limit of the chamber pressure based on the Hoek-Brown criterion.

[0028] Step 4: Solve for the lower limit of the chamber pressure based on the Hoek-Brown criterion.

[0029] The specific steps are as follows: Step 1 is for the cylindrical tunnel-type LRC structure. Since the load is mainly borne by the surrounding rock, the model only considers the main body of the surrounding rock. The A-A' section of the LRC is selected as the core stress analysis object, and the radius of the tunnel is... It is clear that the internal pressure of the energy storage chamber is borne by the chamber. Externally subjected to far-field vertical ground stress With horizontal stress .

[0030] Based on the actual stress characteristics of the engineering, three basic assumptions are made: 1) All deformations occur in a plane perpendicular to the LRC axis, simplifying the three-dimensional problem into a two-dimensional plane strain problem; 2) The surrounding rock is an isotropic medium; 3) The influence of temperature fluctuations on the mechanical properties of the surrounding rock is ignored.

[0031] Step 2: Solve the total stress field of the surrounding rock based on the principle of stress superposition, such as... Figure 2 As shown, this application uses the "perforated infinite thin plate" model from elasticity mechanics to simulate the stress state of the cross-section of the lining chamber. The first stress field represents the compressive stress on the exterior and interior of the perforated infinite thin plate. The corresponding stress field is given by equation (1).

[0032] (1) In the formula , , These represent the radial normal stress, circumferential normal stress, and circumferential shear stress in the first stress field, respectively. This refers to the energy storage pressure applied to the gas storage facility.

[0033] The second stress field involves an infinitely thin plate with a hole subjected to compression in two directions. (To ensure that the total stress at infinity after superposition is equal to the original ground stress) The Kirsch solution for the corresponding stress field is given by equation (2): (2) In the formula , , These are the radial normal stress, circumferential normal stress, and circumferential shear stress in the second stress field, respectively. The radius of the gas storage facility, Radial distance, The lateral stress coefficient in the second stress field. This is the azimuth angle in polar coordinates.

[0034] At the inner wall of the chamber, both the radial normal stress and the circumferential shear stress of the second stress field are zero. , The total stress field is the result of the superposition of equations (1) and (2). The total stress distribution of the inner wall of the surrounding rock is shown in equation (3): (3) In the formula Radial stress, For circumferential stress, For shear stress, This represents the lateral stress coefficient.

[0035] like Figure 3 As shown, the centers of the Mohr circles at various points on the inner wall of the chamber lie between two straight lines, with the intersection point being C(1, ...). When internal pressure Under low internal pressure, the most dangerous stress state corresponds to circle C2, at which point the maximum principal stress is... Minimum principal stress ;when Under high internal pressure, the most dangerous stress state corresponds to circle C4, and the principal stress relationship follows... The changes in the values ​​provide a basis for the stress state in the subsequent analytical solution derivation.

[0036] The above expression for the internal wall stress gives the functional relationship between the maximum and minimum principal stresses at the most critical point and the internal pressure, geostress, and lateral stress coefficient. This relationship will be substituted into the Hoek-Brown criterion in step 3 to solve for the critical internal pressure.

[0037] Step 3 first calculates the core parameters of the Hoek-Brown criterion, based on GSI, , The parameters are calculated using formula (4) to determine the core parameters of the Hoek-Brown criterion. (Rock mass material constants) and (Rock mass constant): (4) In the formula For material constants, To consider the rock mass structure conditions, the rock mass constant is derived from the complete rock mass constant. The result of the reduction is These are parameters that reflect the integrity of the rock mass. To control the degree of nonlinearity of the curve.

[0038] Based on the principal stress relationship of the most dangerous point under high internal pressure given in step 2, substituting it into the Hoek-Brown criterion shown in equation (5) yields the internal pressure when the surrounding rock just enters the plastic state. The equations satisfied. Establish the nonlinear relationship between stress state and rock mass failure: (5) In the formula It represents the uniaxial compressive strength of an intact rock mass.

[0039] It should be noted that the Hoek-Brown criterion is a widely used nonlinear failure criterion in rock mechanics, typically used to predict the maximum principal stress at which rock mass fails, given a known minimum principal stress. In this application, both the maximum and minimum principal stresses of the chamber wall are related to the internal pressure to be determined. There exists a functional relationship, and this relationship varies with the level of internal pressure and the lateral stress coefficient. Therefore, the inverse problem to be solved in this application is to deduce the critical internal pressure at which the surrounding rock just maintains an elastic state, given the functional relationship between the maximum and minimum principal stresses and the Hoek-Brown criterion.

[0040] Directly applying the Hoek-Brown criterion to solve this inverse problem presents some challenges, as the criterion involves nonlinear equations that cannot be solved directly. Furthermore, the expressions for the principal stresses at the most dangerous points differ under low and high internal pressure, requiring separate handling. To address this issue, this application utilizes the stress analysis results from step 2 to clarify the most dangerous points and the corresponding expressions for the maximum and minimum principal stresses in different internal pressure ranges. Secondly, it addresses... For the common case of 0.5 (corresponding to hard rock with high GSI and good integrity), a coordinate transformation is introduced to transform the nonlinear criterion into a simple geometric problem on the scaling plane, thereby deriving explicit analytical solutions for the upper and lower limits of internal pressure.

[0041] Due to the nonlinearity of the Hoek-Brown criterion, it is difficult to directly obtain the upper and lower limit pressure solutions under this criterion. To simplify the calculation, we take... When =0.5, the original principal stress , The coordinate transformation is performed to obtain the "scaling" principal stresses S1 and S3 in the S1-S3 plane. The coordinate transformation "scaling" formula of the principal stress is shown in equation (6).

[0042] (6) Furthermore, combined Figure 4 The geometric relationship of the scaled principal stress plane (S3, S1) shown is simplified from the original Hoek-Brown criterion to S1=S3 after coordinate scaling. 0.5+S3. The most dangerous point under high internal pressure. Figure 3 Circle C4 in the scaling plane ( Figure 4 (The text inside is a point) (Located on the straight line S1=S3), the scaling internal pressure is obtained by geometrically solving the intersection of this point and the simplified Hoek-Brown criterion curve, as shown in Equations (7) and (8), and then the upper limit of the actual internal pressure is obtained by inverse transformation of Equation (9).

[0043] (7) (8) (9) Step 4 uses the core parameters and simplified form of the Hoek-Brown criterion obtained in Step 3 to match the Mohr's circle characteristic corresponding to the most dangerous stress on the chamber wall under low internal pressure. Similarly, the most dangerous point under low internal pressure corresponds to... Figure 3 In circle C2, point B' is the point in the scaling plane. The scaling internal pressure is obtained by solving the intersection of this point and the simplified Hoek-Brown criterion curve (see equation (10)). The coefficients in the equation are the same as in equation (8). After inverse transformation, the lower limit of the actual internal pressure is obtained, as shown in equation (11). The solution process is symmetrical to the upper limit, only the critical state is different.

[0044] (10) (11) The safe operating internal pressure range of the LRC chamber is determined by analytical solutions of the upper and lower internal pressure limits.

[0045] The following is a specific implementation example of this application: A case study on the verification of the elastic internal pressure range of a compressed air energy storage lining chamber based on granite parameters.

[0046] First, the known design parameters are obtained, as shown in the table below:

[0047] First, the parameters of the Hoek-Brown rock mass are calculated, given that... =1.7, according to equation (4), substitute the known data to calculate the parameters. :

[0048] Based on the known rock mass parameters and the calculated parameters, substitute them into equation (8) to calculate... , Simplified calculation yields:

[0049] Based on the calculated coefficients , Substituting into formulas (7) and (10), the scaling internal pressure is calculated. , :

[0050] The upper and lower limits of the actual internal pressure are then obtained through inverse transformation:

[0051] Accuracy is ensured through verification: Numerical simulation verification: In this embodiment, a half-domain numerical model is constructed using FLAC3D. The boundary conditions are set as follows: fixed horizontal displacement of the vertical boundary and fixed three-dimensional displacement of the model center. An LRC model is constructed based on FLAC3D software, using the Hoek-Brown constitutive model. Rock mass parameters consistent with the analytical solution are input, and far-field stress is applied. =30 MPa =30 MPa. Simulation of the volume percentage of the plastic zone under different internal pressures. When I=0, the corresponding internal pressure range is [15.8 MPa, 44.2 MPa], and the verification results are reliable.

[0052] like Figure 5 As shown, when the internal pressure is in the range of 15.78 MPa to 44.22 MPa, the volume ratio of the plastic zone of the surrounding rock is I=0 (corresponding to state S3), indicating that the surrounding rock is in an elastic state. The numerical simulation results (curves) are in high agreement with the analytical solution (labeled values) of this embodiment, verifying the accuracy of the analytical solution and meeting the engineering design requirements. It should be noted that when using numerical simulation methods to determine the upper and lower limits of the internal pressure corresponding to the elastic state of the surrounding rock, it is usually necessary to approximate the critical internal pressure value through multiple trial calculations. The calculation process is relatively cumbersome and sensitive to mesh generation and constitutive parameters. However, the analytical solution proposed in this embodiment can directly calculate the minimum and maximum internal pressures explicitly based on rock mechanics parameters and geostress conditions without iterative trial calculations, significantly improving design efficiency.

[0053] Furthermore, the analytical solution in this embodiment addresses the nonlinear parameters in the Hoek-Brown criterion during the derivation process. Simplified processing was performed (taking) =0.5). To verify the impact of this simplification on the calculation results, the analytical solution calculation results under different geological strength indices (GSI) were further compared. The results show that when GSI>50, the error of the minimum internal pressure is less than 10%, and the error of the maximum internal pressure is less than 5%; as GSI increases, the error further decreases, and when GSI=100, the results are completely consistent. Considering that compressed air energy storage lining caverns are usually built in hard rock with good integrity (GSI is generally greater than 50), the analytical solution in this embodiment maintains good calculation accuracy while ensuring calculation simplicity, meeting the engineering design requirements.

[0054] The beneficial effects of this application are as follows: (1) This application derives an analytical solution based on the Hoek-Brown criterion, which more accurately characterizes the nonlinear failure characteristics of jointed rock masses compared with the linear approximation of the Mohr-Coulomb criterion. The error between the analytical solution and the numerical simulation results is less than 10%, and the calculation accuracy is high. (2) The analytical solution does not require complex iteration or numerical simulation. The internal pressure range can be obtained directly through formula calculation, which significantly improves the calculation efficiency and is suitable for rapid evaluation in the CAES engineering design stage. (3) The analytical solution has a wide range of applications, covering various hard rock masses with GSI=30-100 and different construction disturbance scenarios with disturbance factor D=0-1, and has strong engineering applicability.

[0055] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for determining the pressure interval in an underground lining cavern for air energy storage, characterized in that Includes the following steps: S10, obtain the total stress distribution of the inner wall of the lining chamber under the combined action of far-field vertical ground stress and internal pressure, thereby obtaining the functional relationship between the maximum principal stress and minimum principal stress at the most dangerous point and the internal pressure, ground stress and lateral stress coefficient; S20, by performing coordinate transformation on the maximum and minimum principal stresses, simplifies the Hoek-Brown criterion to a linear relationship on the scaling principal stress plane; S30, For high internal pressure conditions, based on the aforementioned functional relationship and the simplified Hoek-Brown criterion, the internal pressure when the surrounding rock just enters the plastic state is calculated as the upper limit of internal pressure; S40, For low internal pressure conditions, based on the aforementioned functional relationship and the simplified Hoek-Brown criterion, the internal pressure when the surrounding rock just enters the plastic state is calculated as the lower limit of internal pressure. S50, the safe operating internal pressure range of the lining chamber is determined by the upper limit and lower limit of the internal pressure; In step S30, the upper limit of internal pressure is determined as follows: Under high internal pressure conditions, the most dangerous point on the scaled principal stress plane is located on the straight line S1=S3. The intersection of this point and the simplified Hoek-Brown criterion curve is then calculated to obtain the upper limit of the scaled internal pressure. Then, the actual upper limit of internal pressure is obtained through inverse coordinate transformation. ,in , This corresponds to the rock mass material constant and rock mass constant in the Hoek-Brown criterion. S1 represents the uniaxial compressive strength of the intact rock mass, S2 represents the scaled maximum principal stress, and S3 represents the scaled minimum principal stress. The upper limit of the scaling internal pressure for: In the formula, The lateral stress coefficient in the total stress field; The far-field vertical ground stress; In step S40, the lower limit of internal pressure is determined as follows: Under low internal pressure conditions, the most critical point on the scaled principal stress plane is determined, and the intersection of this point and the simplified Hoek-Brown criterion curve is calculated to obtain the scaled lower limit of internal pressure. Then, the lower limit of the actual internal pressure is obtained through inverse coordinate transformation. ; The scaling internal pressure lower limit for: 。 2. The method for determining the internal pressure zone of an underground lining tunnel for air energy storage as described in claim 1, characterized in that, In step S10, the total stress distribution is obtained by superimposing the first stress field and the second stress field; The first stress field is: ;in, , , These are the radial normal stress, circumferential normal stress, and circumferential shear stress in the first stress field, respectively. The internal pressure; The second stress field is: ;in, , , These are the radial normal stress, circumferential normal stress, and circumferential shear stress in the second stress field, respectively. The radius of the gas storage facility; Radial distance; The lateral stress coefficient in the second stress field; The azimuth angle is in polar coordinates; , The far-field vertical ground stress; The total stress distribution is as follows: ;in, The radial stress in the total stress field; The circumferential stress in the total stress field; denoted as the shear stress in the total stress field.

3. The method for determining the internal pressure zone of an underground lining tunnel for air energy storage as described in claim 1, characterized in that, It also includes the calculation of the core parameters of the Hoek-Brown criterion prior to step S20: based on the geological strength index GSI and the intact rock mass constant. The rock mass material constants are calculated using the following formula, along with the construction disturbance factor D. Rock mass constant and nonlinear parameters : 。 4. The method for determining the internal pressure zone of an underground lining tunnel for air energy storage as described in claim 3, characterized in that, In step S20, the coordinate transformation uses the following formula: In the formula, This is the maximum principal stress; It is the minimum principal stress.

5. The method for determining the internal pressure zone of an underground lining tunnel for air energy storage as described in claim 3, characterized in that, In step S20, when the nonlinear parameter in the Hoek-Brown criterion... When the value is 0.5, the simplified linear relationship is expressed on the scaled principal stress plane as follows: S1 = S3 0.5 + S3.

6. A system for determining the internal pressure zone of an underground lining tunnel for air energy storage, characterized in that, The steps for implementing the method for determining the internal pressure zone of an air-storage underground lining tunnel according to any one of claims 1 to 5 include: The stress distribution acquisition module is used to acquire the total stress distribution of the inner wall of the lining chamber surrounding rock under the combined action of far-field stress and internal pressure, thereby obtaining the functional relationship between the maximum and minimum principal stresses at the most dangerous point and the internal pressure, ground stress and lateral stress coefficient; The coordinate transformation module is used to perform coordinate transformation on the maximum principal stress and the minimum principal stress, simplifying the Hoek-Brown criterion into a linear relationship on the scaling principal stress plane. The internal pressure upper limit solution module is used to solve the internal pressure when the surrounding rock just enters the plastic state, based on the aforementioned functional relationship and the simplified Hoek-Brown criterion, for high internal pressure working conditions, as the internal pressure upper limit; The internal pressure lower limit solution module is used to solve the internal pressure when the surrounding rock just enters the plastic state, based on the aforementioned functional relationship and the simplified Hoek-Brown criterion, for low internal pressure working conditions, as the internal pressure lower limit. The safety range determination module is used to determine the safe operating internal pressure range of the lining chamber from the upper limit and the lower limit of the internal pressure.

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