Composite lining high-pressure gas storage suitable for soft rock roadway and construction method

Abstract

The invention discloses a composite lining high-pressure gas storage suitable for a soft rock roadway and a construction method, and relates to the technical field of compressed air underground energy storage. The composite lining high-pressure gas storage suitable for the soft rock roadway comprises a lining structure arranged in the soft rock roadway, reinforced concrete force transmission piles arranged on the outer side of the lining structure in the circumferential direction, and reinforcing steel bars arranged on the outer side of the lining structure; and the other end extends into the soft rock roadway in the direction away from the lining structure. When the lining structure is subjected to pressure of internal high-pressure air, the pressure is transmitted to the reinforced concrete force transmission piles from the lining structure, the reinforced concrete force transmission piles generate friction with the soft rock roadway in the length direction, and in other words, the pressure generated by the high-pressure air from inside to outside is converted into friction force between the reinforced concrete force transmission piles and the soft rock roadway; compared with the prior art, high-pressure air pressure can be prevented from being directly ballasted in the soft rock roadway, the structural stability of the soft rock roadway is maintained, and application of the compressed air energy storage structure in the soft rock roadway is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of compressed air underground energy storage, and in particular to a composite lining high-pressure gas storage suitable for soft rock tunnels and a construction method. Background Art

[0002] Compressed air energy storage is a large-scale energy storage technology that can solve the problems of intermittency and uncertainty in renewable energy generation such as wind and solar energy, and has good application prospects.

[0003] At present, the sites of compressed air energy storage power stations in artificially excavated composite lined chambers are all hard rock formations. The reason is that hard rock has high strength and rigidity and can bear the pressure transmitted by high-pressure gas through reinforced concrete lining. However, the surrounding rock of the tunnels in the domestic coal-bearing sedimentary rock formations is mostly soft rock, and its strength and rigidity cannot bear the pressure transmitted by high-pressure gas. According to experiments, a gas storage reservoir built in a soft rock formation with a conventional "surrounding rock-lining-sealing layer" structure, when subjected to 10MPa high-pressure gas, the surrounding rock deformed significantly, causing cracks in the concrete lining and damage to the sealing layer steel plate, which eventually led to the failure of the gas storage reservoir seal.

[0004] In view of this, how to provide a compressed air energy storage structure suitable for soft rock tunnels is a problem that technical personnel in this field urgently need to solve. Summary of the invention

[0005] The purpose of the present invention is to provide a composite lining high-pressure gas storage suitable for soft rock tunnels and a construction method to solve the problems existing in the prior art.

[0006] To achieve the above object, the present invention provides a composite lining high-pressure gas storage suitable for soft rock tunnels, comprising:

[0007] A lining structure is arranged in a soft rock tunnel, wherein a compressed air storage cavity is defined inside the lining structure;

[0008] The reinforced concrete force transfer pile is arranged on the outer side of the lining structure along the circumferential direction, one end of which is connected to the lining structure, and the other end extends into the soft rock tunnel in a direction away from the lining structure.

[0009] Furthermore, the lining structure comprises:

[0010] A reinforced concrete lining layer is arranged in a soft rock tunnel, wherein the reinforced concrete lining layer is a cylindrical structure with a hollow interior, and the reinforced concrete force transfer piles are connected to the reinforced concrete lining layer;

[0011] A sealing steel plate is arranged on the inner surface of the reinforced concrete lining layer and a sliding layer is arranged between the sealing steel plate and the reinforced concrete lining layer; the sealing steel plate is used to enclose a compressed air storage cavity, and the sliding layer is used to reduce the friction between the sealing steel plate and the reinforced concrete lining layer to prevent the steel plate from buckling and damage.

[0012] Furthermore, the sliding layer is composed of asphalt, expanded perlite and fly ash, and the ratio is asphalt: expanded perlite: fly ash = 0.5-1: 0.2-0.6: 0.8-1.4, and the thickness of the sliding layer is 3-8 cm.

[0013] Furthermore, the sealing steel plate has a thickness of 5-15 mm.

[0014] Furthermore, the thickness of the reinforced concrete lining layer is 40-50 cm.

[0015] Furthermore, the reinforced concrete force transfer pile is cylindrical, has a diameter of 20-30 cm, and is embedded in the soft rock tunnel at a depth of 10-15 m.

[0016] Furthermore, the reinforced concrete force-transfer pile has a pile head steel bar, and the pile head steel bar is anchored in the concrete lining layer, and the anchoring length is at least 50 cm.

[0017] The present invention also provides a composite lining high-pressure gas storage construction method suitable for soft rock tunnels, comprising the following steps:

[0018] S1: Expand the section of the soft rock tunnel to form a cylindrical cavern, and spray concrete on the inner wall of the cylindrical cavern for initial support;

[0019] S2: Drill pile holes in the cylindrical cavern in the horizontal direction and put in the force-transfer pile reinforcement cage, expose the pile head reinforcement in the cylindrical cavern with an exposed length of 70 cm, and pour concrete into the pile hole to form a reinforced concrete force-transfer pile;

[0020] S3: Tie the lining steel skeleton in the cylindrical cavern, the lining steel skeleton is close to the inner wall of the cylindrical cavern, bend the pile head steel bars into the lining steel skeleton, the anchor length is at least 50cm, set up the formwork and pour concrete, and pour the reinforced concrete lining layer on the inner wall of the cylindrical cavern;

[0021] S4: correct the inner surface of the reinforced concrete lining layer and lay a sliding layer on the inner surface of the reinforced concrete lining layer;

[0022] S5: A sealing steel plate is installed on the inner surface of the slip layer to form a compressed air storage cavity surrounded by the sealing steel plate.

[0023] Furthermore, the inner surface of the sealing steel plate is coated with an anti-corrosion and anti-rust coating.

[0024] The present invention discloses the following technical effects:

[0025] 1. The lining structure is set in the soft rock tunnel, and reinforced concrete force transfer piles are arranged along the circumference of the lining structure. When the lining structure is subjected to the pressure of the internal high-pressure air, the pressure is transmitted from the lining structure to the reinforced concrete force transfer piles. The reinforced concrete force transfer piles generate friction with the soft rock tunnel along the length direction, that is, the pressure generated by the high-pressure air from the inside to the outside is converted into the friction between the reinforced concrete force transfer piles and the soft rock tunnel. Compared with the existing technology, it can avoid the direct ballast of high-pressure air pressure on the soft rock tunnel, maintain the structural stability of the soft rock tunnel, and realize the application of compressed air energy storage structure in soft rock tunnel.

[0026] 2. In the lining structure, the outermost reinforced concrete lining layer is connected to the reinforced concrete force transfer pile, and the innermost sealing steel plate is connected to the high-pressure air. A sliding layer is set between the two. The purpose is to convert the pressure generated by the high-pressure air into a radial force in the same direction as the reinforced concrete force transfer pile, reduce the friction between the sealing steel plate and the reinforced concrete lining layer, and prevent the steel plate from buckling and damage, thereby ensuring that the air pressure is stably converted into the friction between the reinforced concrete force transfer pile and the soft rock tunnel, further improving the structural stability of the soft rock tunnel. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0029] Figure 2 This is a schematic diagram of the lining structure;

[0030] Figure 3 It is a schematic diagram of the internal steel bars of the lining structure and reinforced concrete force-transfer piles;

[0031] Among them, 1. Sealing steel plate; 2. Sliding layer; 3. Reinforced concrete lining layer; 4. Reinforced concrete force transfer piles; 5. Soft rock tunnel; 6. Longitudinal common steel bars; 7. Unusual steel bars; 8. Pile stirrups; 9. Outer steel mesh; 10. Lining stirrups; 11. Inner steel mesh. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0034] An embodiment of the present invention provides a composite lined high-pressure gas storage reservoir suitable for soft rock tunnels, comprising: a lining structure, which is arranged in the soft rock tunnel 5, and a compressed air storage cavity is defined inside the lining structure; reinforced concrete force transfer piles 4, which are radially arranged on the outside of the lining structure, one end of which is connected to the lining structure, and the other end extends into the soft rock tunnel 5 in a direction away from the lining structure.

[0035] In this embodiment, the lining structure includes: a reinforced concrete lining layer 3, which is arranged in a soft rock tunnel 5, and the reinforced concrete lining layer 3 is a cylindrical structure with a hollow interior, and reinforced concrete force-transfer piles 4 are evenly spaced radially and connected to the reinforced concrete lining layer 3; a sealing steel plate 1 is arranged on the inner surface of the reinforced concrete lining layer 3, and a sliding layer 2 is arranged between the sealing steel plate 1 and the reinforced concrete lining layer 3; the sealing steel plate 1 is used to enclose a compressed air storage cavity, and the sliding layer 2 is used to convert the pressure of the compressed air on the sealing steel plate 1 into a radial force and act on the reinforced concrete lining layer 3. In some other embodiments, in order to improve the force transmission effect of the reinforced concrete force-transfer piles 4, multiple groups of reinforced concrete force-transfer piles 4 can be arranged along the length direction of the reinforced concrete lining layer 3, and the setting interval and setting number of the same group of reinforced concrete force-transfer piles 4 can also be adjusted according to the actual environment of the soft rock tunnel 5.

[0036] In this embodiment, the sliding layer 2 is composed of asphalt, expanded perlite and fly ash, and the ratio is asphalt: expanded perlite: fly ash = 1:0.4:1.1. The thickness of the sliding layer 2 is 5 cm. 。 The sealing steel plate 1 is made of Q355R steel plate with a thickness of 5-15 mm. The thickness of the reinforced concrete lining layer 3 is 40-50 cm. The reinforced concrete force-transfer pile 4 is cylindrical with a diameter of 20-30 cm and a depth of 10-15 m embedded in the soft rock tunnel 5. The reinforced concrete force-transfer pile 4 has a pile head steel bar, which is anchored in the concrete lining layer with an anchoring length of at least 50 cm.

[0037] The construction method of the composite lining high-pressure gas storage applicable to the soft rock roadway 5 comprises the following steps:

[0038] S1: Excavate the section 5 of the soft rock tunnel to form a cylindrical cavern, and spray concrete on the inner wall of the cylindrical cavern for initial support;

[0039] S2: Drill pile holes in the cylindrical cavern in the horizontal direction and put in the force-transfer pile reinforcement cage, expose the pile head reinforcement in the cylindrical cavern with an exposed length of 70 cm, and pour concrete into the pile hole to form a reinforced concrete force-transfer pile 4; Figure 3 As shown, the reinforced concrete force-transfer pile 4 is provided with longitudinal common steel bars 6, non-usual steel bars 7 and pile body stirrups 8 (the three constitute a force-transfer pile reinforcement cage), and the end of the longitudinal common steel bars 6 and non-usual steel bars 7 close to the cylindrical cavity is the pile head reinforcement;

[0040] S3: Tie a lining steel skeleton in the cylindrical cavern, the steel skeleton specifically comprising an outer steel mesh 9, an inner steel mesh 11 and lining stirrups 10, the lining steel skeleton is close to the inner wall of the cylindrical cavern, the pile head steel is bent and anchored into the lining steel skeleton, the anchoring length is at least 50 cm, a formwork is set up and concrete is poured, and a reinforced concrete lining layer 3 is poured on the inner wall of the cylindrical cavern;

[0041] S4: correcting the inner surface of the reinforced concrete lining layer 3 and laying the sliding layer 2 on the inner surface of the reinforced concrete lining layer 3;

[0042] S5: A sealing steel plate 1 is installed on the inner surface of the slip layer 2, and a compressed air storage cavity is surrounded by the sealing steel plate 1. The inner surface of the sealing steel plate 1 is coated with an anti-corrosion and anti-rust coating.

[0043] In the soft rock tunnel 5 in the western mining area, a composite lining high-pressure gas storage test site is constructed according to the above embodiment. The soft rock tunnel 5 specifically contains phyllite, carbonaceous phyllite and carbonaceous slate.

[0044] After the construction is completed, the test point is subjected to a pressure test. In the prior art, the pressure range of high-pressure air storage is usually between 70-100 bar, so the preset working pressure of the high-pressure gas storage structure is generally 10 MPa (about 100 bar). This pressure test uses 10 MPa as the basic test pressure, and the test time is 30 days. The results are as follows:

[0045]

[0046] It can be seen from the above table that when the air pressure reaches 12 MPa, the soft rock tunnel 5 can still maintain structural stability without cracks and deformation. 12 MPa is far beyond the high-pressure air storage pressure, proving that this embodiment can establish a stable and reliable composite lining high-pressure gas storage in the soft rock tunnel 5.

[0047] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0048] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A composite lining high-pressure gas storage suitable for soft rock tunnels, characterized in that: include: A lining structure is arranged in a soft rock tunnel (5), wherein a compressed air storage cavity is defined inside the lining structure; The reinforced concrete force transfer pile (4) is arranged on the outer side of the lining structure along the circumferential direction, one end of which is connected to the lining structure, and the other end of which extends into the soft rock tunnel (5) in a direction away from the lining structure.

2. The composite lining high-pressure gas storage suitable for soft rock tunnels according to claim 1, characterized in that: The lining structure comprises: A reinforced concrete lining layer (3) is arranged in a soft rock tunnel (5); the reinforced concrete lining layer (3) is a cylindrical structure with a hollow interior; and the reinforced concrete force-transfer piles (4) are connected to the reinforced concrete lining layer (3); A sealing steel plate (1) is arranged on the inner surface of a reinforced concrete lining layer (3), and a sliding layer (2) is arranged between the sealing steel plate (1) and the reinforced concrete lining layer (3); the sealing steel plate (1) is used to enclose a compressed air storage cavity.

3. The composite lining high-pressure gas storage suitable for soft rock tunnels according to claim 2, characterized in that: The sliding layer (2) is composed of asphalt, expanded perlite and fly ash, and the ratio is asphalt: expanded perlite: fly ash = 0.5-1: 0.2-0.6: 0.8-1.

4. The thickness of the sliding layer (2) is 3-8 cm.

4. The composite lining high-pressure gas storage suitable for soft rock tunnels according to claim 2, characterized in that: The sealing steel plate (1) has a thickness of 5-15 mm.

5. The composite lining high-pressure gas storage suitable for soft rock tunnels according to claim 2, characterized in that: The thickness of the reinforced concrete lining layer (3) is 40-50 cm.

6. The composite lining high-pressure gas storage suitable for soft rock tunnels according to claim 2, characterized in that: The reinforced concrete force-transfer pile (4) is cylindrical, has a diameter of 20-30 cm, and is embedded in the soft rock tunnel (5) to a depth of 10-15 m.

7. A composite lining high-pressure gas storage suitable for soft rock tunnels according to claim 6, characterized in that: The reinforced concrete force-transfer pile (4) has a pile head steel bar, and the pile head steel bar is anchored in the concrete lining layer, and the anchoring length is at least 50 cm.

8. A composite lining high-pressure gas storage construction method suitable for soft rock tunnels, characterized in that: The following steps are involved: S1: Expand the section of the soft rock tunnel (5) to form a cylindrical cavern, and spray concrete on the inner wall of the cylindrical cavern for initial support; S2: Drill a pile hole in the cylindrical cavern in the horizontal direction and place a force-transfer pile reinforcement cage in it, expose the pile head reinforcement in the cylindrical cavern with an exposed length of 70 cm, and pour concrete into the pile hole to form a reinforced concrete force-transfer pile (4); S3: Tie a lining steel skeleton in the cylindrical cavern, with the lining steel skeleton close to the inner wall of the cylindrical cavern, bend and anchor the pile head steel bars into the lining steel skeleton, with the anchoring length being at least 50 cm, set up a formwork and pour concrete, and pour concrete on the inner wall of the cylindrical cavern to form a reinforced concrete lining layer (3); S4: correcting the inner surface of the reinforced concrete lining layer (3) and laying a sliding layer (2) on the inner surface of the reinforced concrete lining layer (3); S5: A sealing steel plate (1) is installed on the inner surface of the slip layer (2), and a compressed air storage cavity is enclosed by the sealing steel plate (1).

9. The construction method of a composite lining high-pressure gas storage applicable to soft rock tunnels according to claim 8, characterized in that: The inner surface of the sealing steel plate (1) is coated with an anti-corrosion and anti-rust coating.

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