Coal roadway compressed air reservoir air plug construction method and air plug

Abstract

The present application relates to a kind of coal lane compressed air reservoir gas plug construction method and gas plug, comprising the following steps: the stratum of gas plug periphery is grouted and reinforced, and the grouting reinforced area around gas plug is formed;According to the section contour shape of gas plug, the grouting reinforced area corresponding to the position of gas plug outside coal lane is expanded and excavated, and the gas plug pouring cavity corresponding to the shape of gas plug is formed, and the cavity surface of gas plug pouring cavity is the interface of surrounding rock and gas plug;Multiple grouting sealing pipes are arranged along the interface of surrounding rock and gas plug, and multiple air leakage monitoring pipes are arranged in the gas plug pouring cavity, and the air inlet end of air leakage monitoring pipe extends to the interface of surrounding rock and gas plug, wherein air leakage monitoring pipe is provided with pressure detection element and switch valve, and grouting sealing pipe is also provided with switch valve;Concrete is poured in the gas plug pouring cavity to the gas plug, and the construction method of the present application is good in sealing, suitable for the sealing requirement of coal lane compressed air reservoir.

Description

Technical Field

[0001] This invention relates to the field of compressed air storage technology in coal roadways, specifically to a method for constructing an air plug for a compressed air storage facility in a coal roadway and the air plug itself. Background Technology

[0002] The statements herein provide only background information in relation to this invention and do not necessarily constitute prior art.

[0003] Current research on underground structures for air storage mainly focuses on salt caverns, newly constructed hard rock chambers, and abandoned coal mine roadways. Utilizing closed coal mine roadways as gas storage facilities can also effectively improve the utilization rate of underground space, showing broad technological and application prospects.

[0004] The airtightness of a coal mine compressed air storage chamber is affected by multiple factors, including the fatigue bearing capacity and permeability of the lining material, and the joint between the air plug and the surrounding rock. The air plug, a unique sealing structure in coal mine compressed air storage, divides abandoned roadways into different sections. During construction, the concrete shrinks due to water loss during curing, causing the interface between the air plug and the surrounding rock to detach with age, resulting in cracks that can become major leakage channels during storage operation and maintenance. Once leakage occurs, the leak point is often unclear, making subsequent crack repairs difficult. Therefore, designing a scientifically sound and reasonable air plug structure and corresponding construction methods suitable for coal mine compressed air storage is crucial and of great significance.

[0005] The existing patent, CN 206205934 U, discloses a sealing plug for an underground water-sealed oil storage tunnel. The sealing plug body is embedded in the rock mass between a first connecting tunnel and a second connecting tunnel. The sealing plug body has a frustum-shaped structure. At least six filling grouting pipes and four venting pipes are arranged at the dome of the sealing plug body. At least fifteen contact grouting pipes are arranged around the sealing plug body. All the filling grouting pipes, venting pipes, and contact grouting pipes penetrate at least 10 cm through the contact surface between the concrete and the surrounding rock. The arrangement of the filling grouting pipes, venting pipes, and contact grouting pipes ensures that there is no leakage at the contact points with the rock mass, thus isolating the oil storage tunnel. However, the liquid permeability and gas permeability of the rock mass and the gas plug structure are two different concepts. The compressed air energy storage chamber stores high-temperature and high-pressure gas (high temperature: over 120℃, high pressure: 10-20MPa), which requires higher stability and airtightness of the structure. The above technology, which relies solely on sealing plugs for sealing, is prone to leakage when applied to compressed air storage tanks and is not suitable for sealing gases. Moreover, the above patents cannot monitor gas or liquid leakage. In addition, the cross-section of the gas plug in the above patents is horseshoe-shaped, which is not conducive to the stress on the gas plug, and it is easier for leakage channels to form between the gas plug and the surrounding rock.

[0006] Patent application CN115559587A discloses a gas plug structure for a gas storage tank with a reasonable force flow arc. The structure includes a main body, an internal gas storage tank structure, and a reinforcing layer at the top. The reinforcing layer, lining layer, and sealing layer constitute the overall structure of the gas storage tank. The upper side of the reinforcing layer is connected to an upper tie rod via springs and hinge supports. The upper arch structure, the first hinge support, the tie rod, and the prestressing device assembly constitute the upper gas plug. The bottom of the upper gas plug is connected to a first spring and a second spring via tie rods and hinge supports. A prestressing device is located in the middle of the tie rod. The apex of the upper gas plug is the first hinge support structure. The upper gas plug structure is a hollow arched structure. This gas plug structure is reasonably designed and effectively reduces the tensile stress inside the gas plug. However, due to limitations in materials and processes such as the springs and hinge supports, it is difficult to meet the gas storage requirements of large-capacity storage tanks of tens of thousands of cubic meters during actual construction. In summary, existing patents are insufficient to meet the construction requirements for the sealing renovation of abandoned mines. Summary of the Invention

[0007] To address the shortcomings of existing technologies, the purpose of this invention is to provide a method for constructing airlocks in compressed air storage tanks in coal mine roadways, which meets the sealing requirements for converting abandoned mines into compressed air storage tanks.

[0008] To achieve the above objectives, the present invention is implemented through the following technical solution:

[0009] In a first aspect, embodiments of the present invention provide a method for constructing an air plug in a compressed air storage tank in a coal roadway, comprising the following steps:

[0010] Grouting is performed on the strata surrounding the gas plug to form a grouting reinforcement zone around the gas plug.

[0011] Based on the cross-sectional outline shape of the gas plug, the grouting reinforcement area corresponding to the gas plug location on the outside of the coal roadway is expanded to form a gas plug casting cavity corresponding to the shape of the gas plug. The cavity surface of the gas plug casting cavity is the interface between the surrounding rock and the gas plug.

[0012] Multiple grouting and sealing pipes are arranged along the interface between the surrounding rock and the air plug, and multiple air leakage monitoring pipes are installed in the air plug casting cavity. The air inlet of the air leakage monitoring pipe extends to the interface between the surrounding rock and the air plug. The air leakage monitoring pipe is equipped with a pressure detection element and a switch valve, and the grouting and sealing pipe is also equipped with a switch valve.

[0013] Concrete is poured into the air plug inside the air plug casting cavity.

[0014] Optionally, the grouting reinforcement area includes a first grouting reinforcement area and a second grouting reinforcement area, wherein the first grouting reinforcement area is located outside the coal roadway, with one end extending to the junction of the coal roadway lining and the air plug, and the other end extending to a set position outside the coal roadway, and the second grouting reinforcement area is located outside the air plug setting area.

[0015] Optionally, the first and second grouting reinforcement zones may be constructed using a full-section curtain grouting process.

[0016] Optionally, the radius of the grouting reinforcement zone is twice the maximum radius of the air plug casting cavity.

[0017] Optionally, after the grouting reinforcement zone is completed, the grouting effect is evaluated using geophysical exploration methods, and areas that fail the evaluation are reinforced by grouting again.

[0018] Optionally, during the excavation, the arch crown, arch shoulder, arch waist, and arch bottom can be installed in the following order from top to bottom.

[0019] Optionally, the cross-section of the air plug casting cavity is circular, and correspondingly, the air leakage monitoring pipe and the grouting sealing pipe are distributed circumferentially.

[0020] Optionally, the air leakage monitoring pipe includes a monitoring main pipe arranged parallel to the cavity surface of the air plug casting cavity. The monitoring main pipe is provided with multiple monitoring branch pipes distributed along its axial direction. The ends of the monitoring branch pipes extend to the interface between the air plug and the surrounding rock. The section of the monitoring main pipe used to extend out of the air plug is equipped with a pressure detection element and a switching valve.

[0021] Optionally, the leakage monitoring tube is also equipped with a temperature detection element.

[0022] Secondly, embodiments of the present invention provide a compressed air storage plug for a coal roadway, which is constructed using the compressed air storage plug construction method for a coal roadway described in the first aspect.

[0023] Optionally, the compressed air storage plug in the coal roadway adopts a frustum-shaped structure; or a cylindrical structure; or a wedge-shaped structure, including a frustum-shaped first plug part and a second plug part, with the larger ends of the first plug part and the second plug part connected.

[0024] The beneficial effects of this invention are as follows:

[0025] 1. The construction method of this invention features a simple air plug structure that can be constructed using concrete pouring. This method is convenient and easy to implement, avoiding the limitations of materials and processes associated with springs and hinge supports. It meets the gas storage requirements of large-capacity storage facilities with a capacity of tens of thousands of cubic meters. Furthermore, before pouring concrete for the air plug, the surrounding strata at the corresponding location of the air plug are grouted to reinforce the strata, forming a grouted reinforcement zone. This not only prevents subsidence during ground excavation but also provides a sealing effect. In conjunction with the air plug, this achieves a good sealing effect for high-temperature and high-pressure compressed air, reducing the probability of air leakage.

[0026] 2. The construction method of the present invention is equipped with a leakage monitoring pipe, which can monitor the leakage location in real time and then perform timely grouting and sealing, thus avoiding the problem of excessive leakage caused by undetected leakage.

[0027] 3. The construction method of the present invention designs the cross-section of the air plug casting cavity as circular. Correspondingly, the formed air plug cross-section is circular, which is more conducive to stress distribution than the horseshoe-shaped air plug cross-section and is less likely to form air leakage channels, thus meeting the airtightness requirements and being more applicable to coal roadways with different cross-sections. Attached Figure Description

[0028] 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.

[0029] Figure 1 This is a flowchart of the method in Embodiment 1 of the present invention;

[0030] Figure 2 This is a schematic diagram of grouting reinforcement in Embodiment 1 of the present invention;

[0031] Figure 3 This is a schematic diagram of the enlarged excavation in Embodiment 1 of the present invention;

[0032] Figure 4 This is a front view showing the distribution of the air leakage monitoring pipe and the grouting sealing pipe in Embodiment 1 of the present invention;

[0033] Figure 5 This is a side view showing the distribution of the air leakage monitoring pipe and the grouting sealing pipe in Embodiment 1 of the present invention;

[0034] Figure 6 This is a schematic diagram of the air plug structure in Embodiment 2 of the present invention;

[0035] Figure 7 This is a schematic diagram of the air plug structure in Embodiment 3 of the present invention;

[0036] Figure 8 This is a schematic diagram of the air plug structure in Embodiment 4 of the present invention;

[0037] Figure 9 This is a schematic diagram of the air plug structure in Embodiment 5 of the present invention;

[0038] Among them, 1. air plug, 2. stratum, 3. coal roadway lining, 4. cylindrical structure, 5. wedge structure, 6. first air plug part of frustum-shaped structure, 7. cross-sectional profile, 8. first ring grouting pipe, 9. second ring grouting pipe, 10. third ring grouting pipe, 11. upper interface of the first grouting reinforcement zone, 12. fourth ring grouting pipe, 13. fifth ring grouting pipe, 14. sixth ring grouting pipe, 17. upper excavation zone, 18. upper excavation zone, 19. right shoulder excavation zone, 20. left shoulder excavation zone, 21. left waist excavation zone, 22. right waist excavation zone, 23. lower left excavation zone, 24. lower right excavation zone, 25. grouting sealing pipe, 26. air leakage monitoring main pipe, 27. air leakage monitoring branch pipe, 28. first switch valve, 29. pressure gauge, 30. thermometer, 31. second switch valve, 32. grouting perforation. Detailed Implementation

[0039] 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, and do not limit the structure. They are merely for the purpose of facilitating the description of this invention and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0040] Example 1

[0041] This embodiment provides a method for constructing an airlock in a compressed air storage tank in a coal roadway, such as... Figure 1 As shown, it includes the following steps:

[0042] Step 1: Grouting is performed on the outer stratum 2 of the gas plug to form a grouting reinforcement zone.

[0043] The grouting reinforcement zone includes a first grouting reinforcement zone and a second grouting reinforcement zone. The first grouting reinforcement zone is located in the stratum surrounding the coal roadway, with one end extending to the junction of the air plug and the coal roadway lining 3, and the other end extending to a set position outside the coal roadway. The set position is determined according to the actual working conditions. The second grouting reinforcement zone is located outside the air plug, with one end extending to the junction of the air plug and the coal roadway lining, and the other end extending to a set position outside the air plug. The set position is determined according to the actual working conditions.

[0044] like Figure 2 As shown, grouting reinforcement includes the following steps:

[0045] Step 1.1: The first grouting reinforcement zone is pre-grouted using a forward grouting construction process. A full-section curtain grouting method is employed. In this embodiment, grouting is performed in three stages. Ordinary silicate cement grout is injected into the stratum corresponding to the first grouting reinforcement zone through the first ring grouting pipe 8, grouting reinforcement up to the upper interface 11 of the first grouting reinforcement zone. The position of the upper interface 11 of the first grouting reinforcement zone can be determined according to the actual working conditions. Preferably, the upper interface 11 of the first grouting reinforcement zone is such that the radius of the first grouting reinforcement zone is twice the maximum radius of the air plug to be poured. Then, the same method is used to sequentially grout through the second ring grouting pipe 9 and the third ring grouting pipe 10 until the entire first grouting reinforcement zone is formed. The ends of both the first ring grouting pipe 8 and the second ring grouting pipe 9 are inserted into the upper interface 11 of the first grouting reinforcement zone.

[0046] Step 1.2: The second grouting reinforcement zone around the air plug is reinforced using a full-section curtain grouting method. Specifically, a forward grouting process is employed, injecting grout into the formation through the fourth ring grouting pipe 12, the fifth ring grouting pipe 13, and the sixth ring grouting pipe 14 until the grouting reinforcement of the second grouting reinforcement zone is completed. During grouting, the grout is injected to the upper interface of the second grouting reinforcement zone, which is flush with the upper interface 11 of the first grouting reinforcement zone. The fourth ring grouting pipe 12, the fifth ring grouting pipe 13, and the sixth ring grouting pipe 14 are all inserted to the upper interface of the second grouting reinforcement zone.

[0047] After steps 1.1 and 1.2 are completed, geophysical exploration methods are used to evaluate the grouting effect of the first and second grouting reinforcement zones. The grouting range, the density and integrity of the reinforced body are analyzed. For areas that do not meet the requirements, grouting reinforcement is carried out again until the requirements are met.

[0048] Step 2: Determine the boundary 15 of the excavation zone based on the shape of the cross-sectional profile 7 of the gas plug. Based on the boundary 15 of the excavation zone, excavate the grouting reinforcement zone on the outside of the coal roadway 16 corresponding to the gas plug position to form a gas plug casting cavity corresponding to the shape of the gas plug. The cavity surface of the gas plug casting cavity is the interface between the surrounding rock and the gas plug.

[0049] In this embodiment, the cross-section of the air plug casting cavity is circular. During the excavation, the arch top, arch shoulder, arch waist, and arch bottom are installed in sequence from top to bottom.

[0050] The cross-section of the air plug casting cavity is set to be circular, and the corresponding air plug cross-section is circular. Compared with the horseshoe-shaped air plug cross-section, it is more conducive to stress distribution and less likely to form air leakage channels, thus meeting the airtightness requirements and being more applicable to coal roadways with different cross-sections.

[0051] Specifically, such as Figure 3As shown, the excavation zones 17 and 18 above the arch crown are constructed first, followed by the right shoulder excavation zone 19 and left shoulder excavation zone 20 at the arch shoulder. Next, the left waist excavation zone 21 and right waist excavation zone 22 are constructed. Finally, the lower left and lower right excavation zones 23 and 24 are constructed. All excavation zones form an air plug casting cavity that matches the cross-sectional profile of the air plug. No support is required after the air plug casting cavity is constructed.

[0052] Step 3: As Figures 4-5 As shown, multiple grouting and sealing pipes 25 are arranged along the interface between the surrounding rock and the air plug, and multiple air leakage monitoring pipes are installed in the air plug casting cavity. The air inlet end of the air leakage monitoring pipe extends to the interface between the surrounding rock and the air plug. The air leakage monitoring pipe is equipped with a pressure detection element and a switch valve, and the grouting and sealing pipe is also equipped with a switch valve.

[0053] Specifically, the grouting and sealing pipe 25 is arranged at the interface between the surrounding rock and the air plug, so that the grouting hole of the grouting and sealing pipe can be connected with the external space of the air plug, and then the gap between the air plug and the formation can be grouted and sealed through the grouting and sealing pipe 25.

[0054] The leakage monitoring pipe includes a leakage monitoring main pipe 26, the axis of which is parallel to the interface between the surrounding rock and the gas plug. The leakage monitoring main pipe 26 is connected to multiple leakage monitoring branch pipes 27, which are arranged along the axial direction of the leakage monitoring main pipe 26. One end of each leakage monitoring branch pipe 27 is connected to the leakage monitoring main pipe 26, and the other end extends to the interface between the surrounding rock and the gas plug. Leaked gas between the gas plug and the formation can enter the leakage monitoring main pipe 26 through the leakage monitoring branch pipe 27 and then flow out.

[0055] The section of the leak monitoring main pipe 26 extending to the outside of the gas plug is equipped with a first switching valve 28, which is used to control the opening and closing of the leak monitoring main pipe. On the side of the first switching valve 28 away from the gas outlet end of the leak monitoring main pipe 26, a temperature detection element and a pressure detection element are installed on the leak monitoring main pipe. The temperature detection element is a thermometer 30, and the pressure detection element is a pressure gauge 29.

[0056] By installing a leak detection pipe, the leak location can be monitored in real time, allowing for timely grouting and sealing, thus avoiding the problem of excessive air leakage due to undetected leaks.

[0057] The grouting and sealing pipe 25 has grouting holes 32 arranged in its body. The section of the pipe extending to the outside of the air plug is equipped with a second switch valve 31, which is used to control the opening and closing of the grouting and sealing pipe 25.

[0058] In this embodiment, the air leak monitoring pipe and the grouting sealing pipe are independently distributed in the arch crown, arch shoulder, arch waist and arch bottom of the air plug.

[0059] Specifically, the main leakage monitoring pipe and the grouting sealing pipe are distributed at equal intervals along the circumference, and the leakage monitoring pipe and the grouting sealing pipe are set alternately.

[0060] During construction, after the air leakage monitoring pipe and the grouting sealing pipe are positioned, external equipment can be used to fix the pipe section that extends to the outside of the air plug, so that it can be buried in the air plug after subsequent pouring.

[0061] Step 4: After the air leakage monitoring pipe and grouting sealing pipe are erected, concrete is poured into the air plug in the air plug pouring cavity, using the integral pouring method until the air plug pouring is completed.

[0062] The construction method of this embodiment features a simple air plug structure that can be constructed using concrete pouring, making construction convenient and simple. It avoids the limitations of materials and processes such as springs and hinge supports, meeting the gas storage needs of large-capacity storage facilities with a capacity of tens of thousands of cubic meters. At the same time, by expanding the excavation, the air plug is embedded in the soil layer, resulting in a good sealing effect. Before pouring concrete for the air plug, the surrounding strata at the corresponding location of the air plug are grouted to reinforce it, forming a grouted reinforcement zone. This not only prevents the collapse that occurs during the excavation of the strata, but also provides a sealing effect. In conjunction with the air plug, it can achieve a good sealing effect for high-temperature and high-pressure compressed air, reducing the probability of air leakage.

[0063] Example 2

[0064] This embodiment provides a compressed air storage plug for a coal roadway, which is constructed using the compressed air storage plug construction method for a coal roadway described in Embodiment 1.

[0065] like Figure 6 As shown, the air plug is a frustum-shaped structure 1, with its larger end face positioned close to the coal roadway, and the area of ​​the larger end face is greater than the cross-sectional area of ​​the coal roadway.

[0066] Example 3:

[0067] This embodiment provides a compressed air storage plug for a coal roadway, constructed using the compressed air storage plug construction method described in Embodiment 1. Figure 7 As shown, the air plug is a cylindrical structure 4, and its cross-sectional area is larger than that of the coal roadway.

[0068] Example 4:

[0069] This embodiment provides a compressed air storage plug for a coal roadway, constructed using the compressed air storage plug construction method described in Embodiment 1. Figure 8As shown, the gas plug is a wedge-shaped structure 5, including a first gas plug part and a second gas plug part with a frustum-shaped structure. The ends of the first gas plug part and the second gas plug part with larger areas are connected. The first gas plug part and the second gas plug part are symmetrically arranged with respect to the interface. The end face of the second gas plug part with smaller area is fitted to the coal roadway.

[0070] Example 5:

[0071] This embodiment provides a compressed air storage plug for a coal roadway, constructed using the compressed air storage plug construction method described in Embodiment 1. Figure 9 As shown, the gas plug is a wedge-shaped structure, including a first gas plug part 6 and a second gas plug part with a frustum-shaped structure. The larger ends of the first gas plug part and the second gas plug part are connected, and the smaller end face of the second gas plug part is fitted to the coal roadway. The difference between this embodiment and embodiment 4 is that the interface between the first gas plug part and the second gas plug part is closer to the coal roadway.

[0072] In Examples 2, 4, and 5, the angle between the conical surface of the air plug and the axis of the air plug is less than 45°. Those skilled in the art can set the size of the angle according to the actual situation.

[0073] In Examples 2, 3, 4 and 5, air plugs were pre-embedded with air leakage monitoring pipes and grouting sealing pipes.

[0074] Under normal conditions, both the first and second switching valves are in the closed state.

[0075] When an air leak occurs, the leaking gas can enter the main air leak monitoring pipe through the corresponding leak monitoring branch pipe. The amount of air leak is analyzed based on the pressure gauge reading 29, and the size and location of the crack are initially determined. Depending on the size of the crack and construction requirements, grouting materials with different particle sizes and gel times are selected, such as ultrafine cement grout suitable for micro-cracks and cement-water glass dual-liquid grout with extremely fast gel times. The second switch valve 31 of the grouting and sealing pipe corresponding to the leak location is opened, and grouting and sealing are performed on the corresponding leak points in the air plug crown, arch shoulder, arch waist, and arch bottom through the grouting and sealing pipe 25.

[0076] In this embodiment, after air leakage is detected, geophysical exploration methods are used to detect the distribution morphology of the underlying fractures before grouting. After grouting, geophysical exploration methods, such as ground-penetrating radar and transient electromagnetic methods, are used to evaluate the grouting effect. After grouting and sealing, the grouting range, the density and integrity of the reinforced body are inspected to indirectly evaluate the grouting effect.

[0077] According to the radar detection principle, after grouting, the grout fills the gap between the air plug and the surrounding rock interface. The electromagnetic wave reflects less energy at the interface, and the energy attenuation shown in the radar image is not as strong as before grouting. The reflected wave exhibits the characteristics of homogeneity, that is, the waveform is flat, continuous, and has good unidirectionality, which indirectly evaluates the grouting effect.

[0078] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for constructing an air plug for a compressed air storage tank in a coal roadway, characterized in that, Includes the following steps: Grouting is performed on the strata surrounding the gas plug to form a grouting reinforcement zone around the gas plug. The grouting reinforcement area includes a first grouting reinforcement area and a second grouting reinforcement area. The first grouting reinforcement area is located outside the coal roadway, with one end extending to the junction of the coal roadway lining and the air plug, and the other end extending to a designated position outside the coal roadway. The second grouting reinforcement area is located outside the area where the air plug is installed. The first and second grouting reinforcement areas are constructed using a full-section curtain grouting process. Based on the cross-sectional outline shape of the gas plug, the grouting reinforcement area corresponding to the gas plug location on the outside of the coal roadway is expanded to form a gas plug casting cavity corresponding to the shape of the gas plug. The cavity surface of the gas plug casting cavity is the interface between the surrounding rock and the gas plug. Multiple grouting and sealing pipes are arranged along the interface between the surrounding rock and the air plug, and multiple air leakage monitoring pipes are installed in the air plug casting cavity. The air inlet of the air leakage monitoring pipe extends to the interface between the surrounding rock and the air plug. The air leakage monitoring pipe is equipped with a pressure detection element and a switch valve, and the grouting and sealing pipe is also equipped with a switch valve. Concrete is poured into the air plug within the air plug casting cavity; The air leakage monitoring pipe includes a main monitoring pipe arranged parallel to the cavity surface of the air plug casting cavity. The main monitoring pipe is provided with multiple monitoring branch pipes distributed along its axial direction. The ends of the monitoring branch pipes extend to the interface between the air plug and the surrounding rock. The section of the main monitoring pipe used to extend out of the air plug is equipped with a pressure detection element and a switching valve. During the excavation, the arch is installed in the following order from top to bottom: arch crown, arch shoulder, arch waist, and arch bottom. Alternatively, the cross-section of the air plug casting cavity is circular, and correspondingly, the air leakage monitoring pipe and the grouting sealing pipe are distributed circumferentially.

2. The method for constructing an air plug in a compressed air storage tank in a coal roadway as described in claim 1, characterized in that, The radius of the grouting reinforcement zone is twice the maximum radius of the air plug casting cavity.

3. The method for constructing an air plug in a compressed air storage tank in a coal roadway as described in claim 1, characterized in that, After the grouting reinforcement zone is completed, the grouting effect is evaluated using geophysical exploration methods. Areas that fail the evaluation are reinforced by grouting again.

4. The method for constructing an air plug in a compressed air storage tank in a coal roadway as described in claim 1, characterized in that, The leakage monitoring tube is also equipped with a temperature detection element.

5. A compressed air storage plug for a coal roadway, characterized in that, It was constructed using the air plug construction method for compressed air storage tanks in coal roadways as described in any one of claims 1-4.

6. The compressed air storage plug for a coal roadway as described in claim 5, characterized in that, It adopts a frustum-shaped structure; Or a cylindrical structure; Alternatively, a wedge-shaped structure may be provided, comprising a frustum-shaped first and second air plug sections, with the larger ends of the first and second air plug sections connected together.

Images