Method for testing stability of rock-concrete interface in cyclic injection-production of underground compressed air energy storage

Abstract

The application discloses a kind of underground compressed air energy storage depot cycle injection and mining lower rock-concrete interface stability test method, comprising the following steps: (1) rock mass is prepared for the test gas storage chamber test piece, and the inner cavity middle part is filled cavity for forming sealing plug.(2) the inner cavity of the filling cavity two sides is respectively used as gas storage depot, cavity.Utilize sealing material to form sealing plug in the filling cavity, and form the flexible resistance strain gauge of "Z" shape arrangement in the rock-concrete interface between the side wall of sealing plug and the inner side wall of filling cavity.(2) the lead wire is connected with strain detection equipment, the outer port of the gas storage depot is sealed after being filled with gas therein, reaches the set gas pressure, and the strain data of the flexible resistance strain gauge is collected using the strain detection equipment.The method of the application more accurately reveals the cause of leakage by measuring the relative displacement between rock-concrete interface, and provides more scientific technical support for the improvement of the sealing structure of gas storage depot end.

Description

Technical Field

[0001] This invention relates to the field of compressed air energy storage technology, and in particular to a method for testing the stability of the rock-concrete interface during cyclic injection and production in underground compressed air energy storage facilities. Background Technology

[0002] The information disclosed in this background section is intended only to enhance understanding of the overall background of the invention and is not necessarily to be construed as an admission or in any way implying that such information constitutes prior art known to those skilled in the art.

[0003] Compressed air energy storage (CAES) is a method of storing electrical energy by compressing and releasing air. Specifically, during periods of low electricity demand, electrical energy is converted into the internal energy of the gas and stored. During peak demand periods, the high-pressure gas is released to drive a generator, making it a large-scale, low-cost, and green energy storage technology. The underground gas storage structure is a crucial component of a CAES power plant, and its airtightness directly affects the plant's operational performance and reliability. Dedicated excavation or utilization of existing abandoned mine shafts in hard rock chambers is an important underground construction option. Underground CAES storage facilities operate at pressures exceeding 10 MPa, requiring stringent airtightness (a 24-hour leakage rate of no more than 1%). Ensuring that the percentage of gas leakage in the storage facility remains within acceptable limits is critical to determining the energy conversion efficiency and operational safety of the CAES system.

[0004] Current research on the sealing performance of underground gas storage facilities mainly focuses on the sealing performance of the surrounding rock and sealing layer. However, studies have shown that the main leakage channel for gas storage facilities is the sealing structure at the storage end. For example, patent application number 202311554222.3 discloses a device and method for testing the airtightness of the interface between the surrounding rock and structure of a compressed gas storage chamber. This method uses a displacement sensor installed at the tail of the gas plug to collect data on the overall displacement change of the gas plug under different gas pressures, in order to study the sealing performance of the gas plug and provide a reference for the selection and design optimization of gas plugs in underground gas storage facilities. However, this testing method can only measure the overall displacement value between the sealing structure at the storage end and the surrounding rock, and cannot directly measure the specific displacement characteristics of the rock-concrete interface. This makes it difficult to reveal the true internal mechanism of the displacement, which is not conducive to developing more scientific and effective measures to improve interface stability and reduce gas leakage. Summary of the Invention

[0005] To address the aforementioned problems, this invention proposes a method for testing the stability of the rock-concrete interface during cyclic injection and production in underground compressed gas storage facilities. This method can more accurately reveal the causes of leakage by measuring the relative displacement between the rock and concrete interface, providing more scientific technical support for improving the sealing structure at the storage facility end. Specifically, the technical solution of this invention is as follows.

[0006] A method for testing the stability of the rock-concrete interface under cyclic injection and production in an underground compressed gas storage facility includes the following steps: (1) Prepare a gas storage chamber specimen for testing using rock mass, with the middle of the inner cavity being a filling cavity for forming a sealing plug.

[0007] (2) The inner cavities on both sides of the filling cavity are respectively used as a gas storage tank and a cavity. Then, a strip-shaped flexible resistance strain gauge is set on the inner wall of the filling cavity, which includes a resistance wire setting area and a first blank plate and a second blank plate without resistance wires at both ends. The leads connected to both ends of the resistance wires pass through the end of the second blank plate and extend to the outside. A sealing plug is formed in the filling cavity using a sealing material, and the first blank plate is fixed in the inner wall of the filling cavity, and the second blank plate is fixed in the sealing plug. The resistance wire setting area is located in the rock-concrete interface between the side wall of the sealing plug and the inner wall of the filling cavity, and is parallel to the interface, thereby forming the flexible resistance strain gauge with a "Z" shape. The leads of the flexible resistance strain gauge are led out from the outer port of the cavity.

[0008] (3) Connect the lead wire to the strain detection device, seal the outer port of the gas storage tank and fill it with gas. After reaching the set gas pressure, use the strain detection device to collect the strain data of the flexible resistance strain gauge to obtain the relative displacement data between the rock and concrete interface.

[0009] Further, in step (2), the first blank piece is first inserted into the groove in the inner wall of the filling cavity and the two are fixed together. Then, the resistance wire setting area is attached and positioned on the inner wall of the filling cavity. Then, the gas storage chamber is sealed with a sealing plug. Then, with the gas storage chamber specimen vertical and the cavity facing upward, sealing material is poured into the filling cavity until it covers the resistance wire setting area and then the pouring is stopped. Then, the second blank piece is bent so that it is attached to the surface of the sealing material or embedded in the sealing material. Then, the sealing material is poured to fill the filling cavity. After the sealing material hardens, it forms the sealing plug and constructs a flexible resistance strain gauge with the "Z" shape. Finally, the sealing plug is removed. Preferably, the sealing material is gradually injected from the bottom of the filling cavity using a grouting pipe. Optionally, the sealing material includes cement-based materials, etc.

[0010] Furthermore, the filling cavity is provided with multiple layers of the flexible resistance strain gauges.

[0011] Furthermore, the front and back sides of the resistance wire setting area of ​​the "Z"-shaped flexible resistance strain gauge are coated with lubricating oil or paraffin wax.

[0012] Furthermore, the flexible resistance strain gauge also includes two sets of strip-shaped shaping members, respectively arranged across the interface between the resistance wire setting area and the first blank sheet, and the interface between the resistance wire setting area and the second blank sheet. The shaping members include at least one of metal wire, metal strip, and metal sheet, and are insulated from the resistance wire. This allows the second blank sheet to be bent and shaped, facilitating its attachment to the surface of the sealing material or embedding within the sealing material. Optionally, the shaping members are made of at least one of iron, copper, aluminum, zinc, etc.

[0013] Furthermore, step (2) also includes a second type of flexible resistance strain gauge, which is set perpendicular to the rock-concrete interface, and the first blank strain gauge and the second blank strain gauge are respectively fixed in the inner wall of the filling cavity and in the sealing plug. At the same time, the lead wire of the flexible resistance strain gauge is led out from the outer port of the cavity and connected to the strain detection device.

[0014] Furthermore, in step (2), the lead wire of the flexible resistance strain gauge passes through the sealing plug and is led out from the outer port of the cavity.

[0015] Further, in step (2), the resistance wire is sealed between two flexible substrates. Optionally, the substrates may be made of at least one of plastic, rubber, silicone, etc.

[0016] Compared with the prior art, the present invention has at least the following beneficial technical effects: (1) The rock-concrete interface stability testing method of the present invention adopts a method of setting a “Z”-shaped flexible resistance strain gauge in the rock-concrete interface between the side wall of the sealing plug and the inner wall of the filling cavity. It can accurately measure the rock-concrete interface displacement caused by the outward movement of the sealing plug due to the pressure of the high-pressure gas in the gas storage tank, thereby evaluating the stability between the sealing plug and the inner wall of the filling cavity, and providing a reference for improving the stability between the two. To this end, the present invention first provides a flexible resistance strain gauge with a special structure. The first blank plate and the second blank plate at both ends are fixed in the inner wall of the filling cavity and the sealing plug, respectively. The resistance wire setting area between the two can be arranged in parallel in the rock-concrete interface to form the flexible resistance strain gauge with a “Z” shape. This special strain gauge arrangement can effectively avoid the problem that the resistance wire setting area is sheared and broken when the rock-concrete interface is displaced, resulting in the inability to obtain test data. Meanwhile, by fixing the second blank piece with the lead wire in the sealing plug, the lead wire can be led out after passing through the sealing plug without being at the rock-concrete interface, thus avoiding the problem of the lead wire affecting the interface stability and causing a decrease in the accuracy of the test results.

[0017] (2) The present invention also provides a shaping component in the flexible resistance strain gauge that spans the interface (bending interface) between the resistance wire setting area and the first blank gauge and the second blank gauge. This component not only facilitates the shaping of the first blank gauge and the second blank gauge after bending, thereby constructing a strain gauge in a “Z” shape arrangement in the rock-concrete interface, but also increases the firmness of the bending interface, preventing the bending interface from breaking under shear action when the rock-concrete interface shifts, thus preventing the rock-concrete interface shift from being effectively detected.

[0018] (3) In order to cooperate with the flexible resistance strain gauge of the above structure to form a “Z” shaped arrangement, the present invention also proposes a method of segmented casting of sealing material for forming the sealing plug. This not only ensures that the second blank sheet is fixed in the sealing plug, but also avoids the resistance wire setting area from detaching from the inner wall of the filling cavity due to the influence of the sealing material. The final strain gauge arrangement cannot meet the setting requirements, resulting in the problem that the rock-concrete interface misalignment cannot be accurately and effectively identified and tested.

[0019] (4) The present invention also provides a second type of flexible resistance strain gauge at the rock-concrete interface, which can effectively test the phenomenon that the sealing plug separates and becomes unstable due to thermal expansion and contraction caused by the rise and fall of gas temperature in the gas storage tank, resulting in an increase in the gap between the rock-concrete interface. This is also an important reason for gas leakage and energy loss along the rock-concrete interface in the gas storage tank. Its combination with the "Z"-shaped flexible resistance strain gauge can effectively prevent the problem of the rock-concrete interface instability being missed or even incorrectly identified. In addition, the flexible resistance strain gauge of the second type can also monitor the changes in the rock-concrete interface caused by the volume shrinkage of the sealing material during the solidification and hardening process to form the sealing plug, thereby providing data support for solving this problem. Attached Figure Description

[0020] 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.

[0021] Figure 1 The following is a schematic diagram of the structure for testing the stability of the rock-concrete interface in the embodiments below.

[0022] Figure 2 The following is a schematic diagram of the structure of the flexible resistance strain gauge in the embodiments.

[0023] Figure 3 The following is a partial structural schematic diagram of the gas storage chamber specimen in the embodiments below.

[0024] The markings in the above figure represent: 1-Gas storage chamber specimen, 2-Sealing plug, 3-Filling cavity, 4-Gas storage tank, 5-Cavity, 6-Flexible resistance strain gauge, 7-Resistance wire setting area, 8-First blank gauge, 9-Second blank gauge, 10-Lead wire, 11-End cap, 12-Shaping component. Detailed Implementation

[0025] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0026] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms “comprising” and / or “including” are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0027] For ease of description, the words "up," "down," "left," and "right" appearing in this invention only indicate that they are consistent with the up, down, left, and right directions of the accompanying drawings themselves. They do not limit the structure and are merely for the purpose of facilitating the description of this invention and simplifying the description. They do not indicate or imply that the device or component referred to needs to have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0028] The method for testing the stability of the rock-concrete interface during cyclic injection and production in an underground compressed gas storage facility, as described in the accompanying drawings and specific embodiments, is further explained below. Specifically, the testing method includes the following steps: (1) The rock mass collected from the actual engineering chamber to be tested is cut and processed into a gas storage chamber specimen 1 for testing, such as Figure 1 As shown, it is a cylindrical structure with a through-cavity, and the middle of the cavity is a filling cavity 3 for forming a sealing plug 2. This filling cavity 3 has a diameter larger than the inner cavity, so that the wedge-shaped sealing plug 2 can be better secured within the filling cavity 3. Alternatively, a conical filling cavity 3 can be used to form the conical sealing plug 2, or any other suitable filling cavity 3 can be used. The left and right inner cavities of the filling cavity 3 are respectively used as a gas storage tank 4 and a cavity 5. The gas storage tank 4 is used to store high-pressure gas, simulating compressed gas energy storage.

[0029] (2) A strip-shaped flexible resistance strain gauge 6 is provided on the inner wall of the filling cavity 3. Specifically, refer to Figure 2The flexible resistance strain gauge 6 comprises two flexible substrates, the material of which can be selected from plastic, rubber, silicone, etc., to ensure that the strain gauge has good bendability. A resistance wire is sealed in the middle part between the two flexible substrates to form a wire-wound resistance wire setting area 7, and the two flexible substrates are bonded together by an adhesive. The two ends of the resistance wire setting area 7 are not provided with the resistance wire, thus forming a first blank plate 8 and a second blank plate 9. The leads 10 connected to both ends of the resistance wire extend outward from the end of the second blank plate 9. The front and back sides of the substrate of the resistance wire setting area 7 of the flexible resistance strain gauge 6 are coated with lubricating oil (such as silicone oil) or paraffin wax to prevent the resistance wire setting area 7 from sticking to the sidewall of the filling cavity 3 and the sealing plug 2.

[0030] First, insert the first blank piece 8 into the groove in the inner wall of the filling cavity 3 and fix the two together with adhesive. Then, use pressure-sensitive adhesive or other adhesives to attach and fix the resistance wire setting area 7 to the inner wall of the filling cavity 3. Then, seal the gas storage chamber 4 with a sealing plug, and then, in the state where the gas storage chamber specimen 1 is vertical and the cavity 5 is facing upward (refer to...). Figure 3 The sealing material (cement-based material, etc.) is gradually injected from the bottom of the filling cavity 3 using a grouting pipe. Injection stops when the sealing material covers the resistance wire setting area 7. Then, the second blank sheet 9, bent horizontally, is attached to the surface of the sealing material, or bent at a larger angle to embed it in the sealing material. Injection continues to fill the filling cavity 3 with sealing material. After the sealing material hardens, a sealing plug 2 is formed, anchoring the second blank sheet 9 within it. The resistance wire setting area 7 is located precisely at the rock-concrete interface between the side wall of the sealing plug 2 and the inner side wall of the filling cavity 3, and is parallel to this interface, thus constructing the "Z"-shaped flexible resistance strain gauge 6. During the formation of the sealing plug 2, the lead wire 10 at the end of the second blank sheet 9 is embedded in the sealing plug 2, eventually leading out from its end and out through the outer port of the cavity 5. Finally, the sealing plug in the gas storage tank 4 is removed to facilitate subsequent gas filling into the gas storage tank 4 during testing. In addition, multiple layers of the flexible resistance strain gauges 6 can be arranged in the filling cavity 3, each layer including multiple (e.g., 2-4) strain gauges arranged in a ring along the inner wall of the filling cavity 3. The segmented casting method proposed in this embodiment not only ensures that the second blank gauge 9 is fixed in the sealing plug 2, but also avoids the problem that the resistance wire setting area 7 will detach from the inner wall of the filling cavity due to the influence of the sealing material, and the final strain gauge arrangement cannot meet the above-mentioned "Z" shape setting, resulting in the inability to accurately and effectively identify and test the rock-concrete interface misalignment.

[0031] (3) Connect the lead wire 10 to the strain detection device, seal the outer port of the gas storage tank 4 with the end cap 11 or any other suitable component, and then fix the gas storage chamber specimen 1 as a whole. Then, use the inflation device to fill the gas storage tank 4 with gas from the inflation port set on the end cap. After reaching the set pressure, use the strain detection device to collect the strain data of the flexible resistance strain gauge 6 to obtain the relative displacement data between the rock and concrete interface. The larger the relative displacement, the worse the interface stability. This embodiment utilizes a "Z"-shaped flexible resistance strain gauge 6 set in the rock-concrete interface. This not only accurately measures the rock-concrete interface misalignment caused by the outward movement of the sealing plug 2 due to the pressure of the high-pressure gas in the gas storage chamber 4, thus assessing the stability between the sealing plug 2 and the inner wall of the filling cavity 3, but also provides a reference for improving their stability. For example, if the relative displacement data exceeds a set value, it indicates insufficient bonding force between the sealing plug 2 and the filling cavity 3, requiring measures to improve the bonding force and prevent interface instability caused by misalignment. This would lead to leakage of high-pressure gas from the gas storage chamber 4 along the interface and its discharge from the cavity 5, resulting in gas energy loss. Furthermore, the specially structured flexible resistance strain gauge 6 proposed in this embodiment, combined with its "Z"-shaped arrangement in the rock-concrete interface, effectively avoids the problem of the resistance wire setting area 7 being sheared and broken during rock-concrete interface misalignment, preventing the acquisition of test data. Meanwhile, this embodiment also ensures that the lead wire can be led out after passing through the sealing plug 2 by fixing the second blank piece 9 with the lead wire 10 in the sealing plug 2, without being at the rock-concrete interface, thus avoiding the problem of decreased test accuracy caused by the influence of the lead wire on the interface stability.

[0032] In another embodiment, the flexible resistance strain gauge 6 of the above embodiment further includes two sets of strip-shaped shaping members 12. (See reference...) Figure 2 The two sets of shaping elements 12 are respectively arranged across the interface between the resistance wire setting area 7 and the first blank sheet 8, and the interface between the resistance wire setting area 7 and the second blank sheet 9. The shaping elements 12 can be in the form of metal wires, metal strips, metal sheets, etc., and the metal can be selected from iron / iron alloys, copper / copper alloys, aluminum / aluminum alloys, zinc / zinc alloys, etc. Preferably, each set of shaping elements 12 includes multiple metal wires, metal strips, or metal sheets, which are distributed at intervals and parallel to each other in the two flexible substrates of the flexible resistance strain gauge 6, and the shaping elements 12 do not contact the resistance wires distributed in the flexible substrates to ensure that they are in an insulating state and prevent the shaping elements 12 from interfering with the test results.

[0033] In this embodiment, the special structure of the strain gauge formed by combining the shaping component 12 with the flexible resistance strain gauge 6 not only facilitates the bending and shaping of the first blank gauge 8 and the second blank gauge 9 to construct a "Z"-shaped strain gauge arrangement, but also increases the strength of the interface between the resistance wire setting area 7 and the first blank gauge 8 and the second blank gauge 9 (i.e. the interface that needs to be bent), preventing the bent interface from breaking under shear action when the rock-concrete interface shifts, thus preventing the rock-concrete interface shift from being effectively detected.

[0034] In another embodiment, the rock-concrete interface described in the above embodiment is further provided with a second type of flexible resistance strain gauge 6. See details. Figure 1 The flexible resistance strain gauge 6 is positioned perpendicular to the rock-concrete interface, and the first blank strain gauge 8 and the second blank strain gauge 9 are fixed in the inner wall of the filling cavity 3 and the sealing plug 2, respectively. The lead wire 10 of the flexible resistance strain gauge 6 is also led out from the outer port of the cavity 5 and connected to the strain detection device. In this embodiment, this type of strain gauge is used to test the rise and fall of the gas temperature in the gas storage tank 4 (the air temperature can exceed 100°C after filling and drops sharply to -10~-20°C after degassing). Especially under the cyclic injection and production conditions of continuous filling and degassing, the thermal expansion and contraction can easily cause the sealing plug 2 to separate and become unstable from the inner wall of the filling cavity, resulting in an increase in the gap between the rock and concrete interface. This is also an important reason for the leakage of gas along the rock-concrete interface and energy loss in the gas storage tank 4. The "Z"-shaped flexible resistance strain gauge 6 mentioned above is difficult to detect this form of interface instability, which can easily lead to the problem of the cause of rock-concrete interface instability being missed or even incorrectly identified. The combination of these two types of strain gauges can effectively overcome the aforementioned problems, providing a more reliable basis for improving the stability of the rock-concrete interface. Furthermore, the flexible resistance strain gauges of this embodiment can also monitor the changes in the rock-concrete interface caused by volume shrinkage during the solidification and hardening of the sealing material to form the sealing plug 2, thus providing more reliable data support for solving this problem. For example, if the obtained strain data exceeds the set value, it indicates that the volume shrinkage of the sealing material used is too large, making it unsuitable as the forming material of the sealing plug 2, and requiring replacement or improvement of the sealing material.

[0035] Finally, it should be noted that any modifications, equivalent substitutions, or improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention. Although specific embodiments of this invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of this invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of this invention are still within the scope of protection of this invention.

Claims

1. A method for testing the stability of the rock-concrete interface under cyclic injection and production in an underground compressed gas storage facility, characterized in that, Includes the following steps: (1) Prepare gas storage chamber specimens for testing using rock mass, with the middle of the inner cavity being a filling cavity for forming a sealing plug; (2) The inner cavities on both sides of the filling cavity are respectively used as a gas storage tank and an empty cavity; then, a strip-shaped flexible resistance strain gauge is set on the inner wall of the filling cavity, which includes a resistance wire setting area and a first blank plate and a second blank plate without resistance wires at both ends. The leads connected to both ends of the resistance wires pass through the end of the second blank plate and extend to the outside; a sealing plug is formed in the filling cavity using a sealing material, and the first blank plate is fixed in the inner wall of the filling cavity, and the second blank plate is fixed in the sealing plug. The resistance wire setting area is located in the rock-concrete interface between the side wall of the sealing plug and the inner wall of the filling cavity, and is parallel to the interface, thereby forming the flexible resistance strain gauge with a "Z" shape; the leads of the flexible resistance strain gauge are led out from the outer port of the empty cavity. (3) Connect the lead wire to the strain detection device, seal the outer port of the gas storage tank and fill it with gas. After reaching the set gas pressure, use the strain detection device to collect the strain data of the flexible resistance strain gauge to obtain the relative displacement data between the rock and concrete interface. In step (2), the first blank piece is first inserted into the groove in the inner wall of the filling cavity and the two are fixed together. Then, the resistance wire setting area is attached and positioned on the inner wall of the filling cavity. Then, the gas storage tank is sealed with a sealing plug. Then, in the state that the gas storage chamber specimen is vertical and the cavity is facing upward, the sealing material is poured into the filling cavity until it covers the resistance wire setting area and then the pouring is stopped. Then, the second blank piece is bent so that it is attached to the surface of the sealing material or embedded in the sealing material. Then, the sealing material is poured to fill the filling cavity. After the sealing material hardens, it forms the sealing plug and constructs a flexible resistance strain gauge with the "Z" shape. Finally, the sealing plug is removed. The filling cavity is provided with multiple layers of the flexible resistance strain gauges; the flexible resistance strain gauges also have two sets of strip-shaped shaping members, which are respectively arranged across the resistance wire setting area and the interface of the first blank sheet, and the interface of the resistance wire setting area and the second blank sheet. The shaping members include at least one of metal wire, metal strip, and metal sheet, and the shaping members are insulated from the resistance wire. The front and back sides of the resistance wire setting area of ​​the "Z"-shaped flexible resistance strain gauge are coated with lubricating oil or paraffin layer. Step (2) also includes the flexible resistance strain gauge in a second configuration, which is set perpendicular to the rock-concrete interface, and the first blank strain gauge and the second blank strain gauge are fixed in the inner wall of the filling cavity and the sealing plug, respectively; at the same time, the lead wire of the flexible resistance strain gauge is led out from the outer port of the cavity and connected to the strain detection device.

2. The method for testing the stability of the rock-concrete interface under cyclic injection and production in an underground compressed gas storage facility according to claim 1, characterized in that, The sealing material is gradually injected from the bottom of the filling cavity using a grouting pipe.

3. The method for testing the stability of the rock-concrete interface under cyclic injection and production in an underground compressed gas storage facility according to claim 1, characterized in that, The sealing material includes cement-based materials.

4. The method for testing the stability of the rock-concrete interface under cyclic injection and production in an underground compressed gas storage facility according to claim 1, characterized in that, The material of the shaping component includes at least one of iron, copper, aluminum, and zinc.

5. The method for testing the stability of the rock-concrete interface under cyclic injection and production in an underground compressed gas storage facility according to any one of claims 1-4, characterized in that, In step (2), the lead wire of the flexible resistance strain gauge passes through the sealing plug and is led out from the outer port of the cavity.

6. The method for testing the stability of the rock-concrete interface under cyclic injection and production in an underground compressed gas storage facility according to any one of claims 1-4, characterized in that, In step (2), the resistance wire is sealed between two flexible substrates.

7. The method for testing the stability of the rock-concrete interface under cyclic injection and production in an underground compressed gas storage facility according to claim 6, characterized in that, The substrate is made of at least one of plastic, rubber, and silicone.

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