A double-hull underwater concrete dry chamber repair operation method

Abstract

The present invention belongs to the technical field of safety and reinforcement of water conservancy engineering hubs, and discloses a double-hull underwater concrete dry chamber repair operation method, which uses a double-hull underwater concrete dry chamber repair device to enter the water, and after covering the underwater concrete to be repaired, first perform preliminary rubber water stopping, and then perform the operation of pumping water from the outer cabin and inflating the inner cabin, so that a local dry environment relative to the outside is formed inside the double-hull underwater concrete dry chamber repair device, which is convenient for repairing underwater concrete. On the one hand, the water pressure of the external water body is well utilized, the rubber water stopping effect is better, and the overall stability is increased; on the other hand, the gas's discharge effect on the inner cabin water body is well utilized, which can better achieve a dry working environment; in addition, the cooperation of the above two aspects cleverly breaks through the water-stopping and sealing problems under great water depth conditions, and solves the problem of the need for repair under great water depth conditions.

Description

Technical Field

[0001] The present invention belongs to the technical field of safety hazard removal and reinforcement of water conservancy project hubs, and specifically relates to an operation method for underwater concrete repair. Background Art

[0002] The flood discharge and energy dissipation structures of water conservancy projects primarily include overflow dams (channels), plunge pools, spillways, and hydraulic gates. These structures are subjected to the immense impact of high-speed water flows during hydropower station operation. Their concrete slabs are highly susceptible to damage from scouring, cavitation, abrasion, vibration damage, floor splitting, and fractures under these conditions. Once the slabs are damaged, the massive water flow will continuously scour the structure's foundations, and in severe cases, directly destroy the dam foundation. Statistics show that nearly 40% of flood discharge and energy dissipation structures in water conservancy projects, both domestically and internationally, have experienced varying degrees of damage. Once a discharge structure fails, it poses a significant risk to the safe operation of the entire water conservancy project. The continuous scouring of the foundation can easily lead to major accidents such as dam failure, posing a serious threat to the lives and property of people living in downstream cities.

[0003] In existing research and engineering practice, two repair methods are commonly used to repair damaged stilling basin floors: direct underwater repair and dryland repair. However, each of these two repair methods has its own advantages and disadvantages. Direct underwater repair requires underwater treatment of the damaged surface, followed by the use of underwater concrete (epoxy resin, etc.) to repair the damaged part. The advantage is that the water in the stilling basin does not need to be drained, which can save construction time. However, the overall technical difficulty is high, the diving depth of divers is limited, the repair cost is high, the treatment effect is poor, and secondary damage is very likely to occur later. Dryland repair requires that all water in the stilling basin be pumped out to create a dry environment. The advantage is that the damaged part can be thoroughly treated, and the repaired structure can be integrated with the original structure, making it more sturdy and durable. However, the process is time-consuming and the economic cost is huge. Therefore, this research team proposed underwater concrete damage dryland technology, which can create a local dryland environment and effectively solve the shortcomings of the above two existing technologies.

[0004] Partial dryland operations involve enclosing the damaged surface with equipment or a cofferdam, then pumping out the water within the cofferdam, creating a dry environment relative to the surrounding waters. This allows workers to enter and perform pre-treatment and subsequent repairs on the floor. Compared to completely dryland operations, this method eliminates the need to completely pump out the water within the stilling basin; only the water within the cofferdam is pumped out. This method ensures a dry working environment while also significantly reducing costs. For example, the patented pneumatic caisson (patent number: CN200620163305.5) utilizes the concept of partial water pumping. It uses a shield to enclose the damaged structure, then inflates the shield to drain the water, creating a dry working environment. However, this device and method are not ideal for water-stopping. Furthermore, to offset the supporting force of the inflated shield and maintain the balance of the caisson, the device requires tens of tons of ballast blocks, making the entire device heavy and bulky. Furthermore, the device is only suitable for shallow waters and cannot be used for repairs at greater depths. However, in general, the method of using local dry land operations to repair underwater damaged structural surfaces will become an important research direction in the field of water conservancy engineering in the future.

[0005] In summary, the problem of repairing damage to water conservancy projects is urgent. However, previous technical solutions have certain flaws and shortcomings. The main reason is that the water-stopping methods used are relatively ineffective, making it difficult to achieve a local dry land environment, which has a negative impact on construction operations and repair results. In addition, previous methods are mostly only suitable for shallow water depths and are difficult to meet the maintenance needs of deeper water depths. Summary of the Invention

[0006] In view of the shortcomings of the existing technology, the present invention aims to provide a double-hull underwater concrete dry chamber repair method. This method does not require the complete drainage of water from the hydraulic structure to be repaired, but only the drainage of water from the repair device. This method can achieve dry repair of damaged concrete, effectively shorten the construction period, and achieve good construction quality. At the same time, based on the double-hull structure repair device, this method innovatively adopts the operation of pumping water from the outer chamber and inflating the inner chamber. On the one hand, the pumping of water from the outer chamber creates a negative pressure, which effectively utilizes the water pressure of the external water body, allowing the repair device to fit more tightly with the concrete, improving the rubber waterstop effect, and increasing the overall stability. It does not require a large amount of counterweight to achieve a good adhesion between the repair device and the underwater structure surface, reducing the overall weight and material consumption, and saving costs. On the other hand, the inflation method of the inner chamber effectively utilizes the effect of high-pressure gas on the water in the inner chamber, forming a dry chamber in the inner chamber, and better achieving a dry working environment. In addition, the combination of the above two aspects cleverly overcomes the problem of waterstop sealing under deep water conditions and solves the problem of maintenance under deep water conditions.

[0007] In order to solve the above technical problems, the present invention is implemented through the following technical solutions:

[0008] The present invention provides a double-hull underwater concrete drying chamber repair operation method. The method comprises: placing a double-hull underwater concrete drying chamber repair device into water, covering the underwater concrete portion to be repaired, performing preliminary rubber water-stopping, and then performing operations such as pumping water from the outer chamber and inflating the inner chamber. This creates a local dry environment relative to the outside world inside the double-hull underwater concrete drying chamber repair device, thereby facilitating the repair of the underwater concrete.

[0009] The double-hull underwater concrete dry chamber repair device mainly includes an outer cabin and an inner cabin arranged inside the outer cabin. The inner cabin can cover the underwater concrete to be repaired, and the top of the inner cabin is in contact with and directly fixed to the top of the outer cabin.

[0010] An inflation pipe is provided on the top of the outer cabin and the inner cabin, the inflation pipe leads inwardly to the interior of the inner cabin, passes outward through the outer cabin and is connected to an external air compressor or air pump for inflating the inner cabin; a drain pipe is connected to the bulkhead of the outer cabin, the drain pipe is connected to an external water pump for extracting water from the outer cabin;

[0011] The outer cabin bottom is provided with an outer cabin skirt, the bottom surface of the outer cabin skirt is provided with an outer layer of Ω-type water-stop rubber, and the outer edge is provided with an outer layer of VA-type water-stop rubber; the outer layer of VA-type water-stop rubber, the outer layer of Ω-type water-stop rubber, and the outward pumping of water from the drainage pipe constitute the outer layer water-stop barrier of the double-hull underwater concrete dry chamber repair device;

[0012] The bottom of the inner cabin is provided with an inner cabin skirt, the bottom surface of the inner cabin skirt is provided with an inner layer of Ω-type water-stop rubber, and the outer edge is provided with an inner layer of VA-type water-stop rubber; the inner layer of VA-type water-stop rubber, the inner layer of Ω-type water-stop rubber, and the inward inflation of the inflation tube constitute an inner layer water-stop barrier;

[0013] A plurality of support plates are provided between the outer cabin and the inner cabin for supporting force transmission. The plurality of support plates are vertically arranged around the circumference of the inner cabin and arranged in layers, and the plurality of support plates are provided with water / air holes for water and air circulation.

[0014] Furthermore, the outer cabin is a spherical arch structure with a larger diameter, and the inner cabin is a hemispherical structure with a smaller diameter.

[0015] Furthermore, the inflation tube is provided with a one-way check valve to prevent the internal gas from flowing back.

[0016] Furthermore, a plurality of the drainage pipes are evenly arranged around the circumference of the outer cabin.

[0017] Furthermore, the drain pipe is arranged vertically, with the water inlet at the bottom end thereof extending to the bottom of the outer cabin, and the water outlet at the top end thereof leading to the outside of the outer cabin.

[0018] Furthermore, the drain pipe is provided with a one-way check valve to prevent external water from flowing back into the outer cabin.

[0019] Furthermore, the multi-layer support plate includes an inner support plate and an outer support plate, the inner support plate is located between the bulkhead of the inner cabin and the bulkhead of the outer cabin, and the outer support plate is located between the inner cabin skirt plate and the bulkhead of the outer cabin.

[0020] Further, the following steps are included:

[0021] (1) The double-shell underwater concrete dry chamber repair device enters the water and sits on the bottom around the underwater concrete where the repair is to be repaired, and the outer VA-type water-stop rubber 3, the outer Ω-type water-stop rubber 6, the inner VA-type water-stop rubber 12 and the inner Ω-type water-stop rubber 11 are in contact with the surface of the underwater concrete, and the initial rubber compression and water-stopping work are completed by the weight of the entire repair device in the water;

[0022] (2) After the outer layer VA type water-stop rubber, the outer layer Ω type water-stop rubber, the inner layer VA type water-stop rubber and the inner layer Ω type water-stop rubber are completely adhered to the surface of the underwater concrete, and the double-shell underwater concrete dry chamber repair device is overall stable, the water in the outer chamber is pumped out to the external water body through the drainage pipe; due to the effect of pumping water, the upper part of the outer chamber gradually forms a negative pressure state relative to the external water body, so that the double-shell underwater concrete dry chamber repair device is subjected to the pressure of the external water body; at the same time, the inner chamber is inflated through the inflation pipe, and as the gas enters the internal space of the inner chamber, The water in the inner cabin is pressed against the outer cabin and pumped away through the drain pipe; due to the effect of inflation, a positive pressure state is formed in the upper part of the inner cabin, so that the double-hull underwater concrete dry chamber repair device is subjected to the top support force of the internal gas. This process requires controlling the pumping rate to be greater than the inflation rate to ensure that the external water pressure on the double-hull underwater concrete dry chamber repair device is always greater than the top support force of the internal gas, thereby achieving its adsorption at the damaged surface and ensuring its underwater stability; until the water inside the inner cabin is completely drained, stop inflation, and when the water level in the outer cabin is lower than the pumping requirement water level of the drain pipe, stop pumping.

[0023] Furthermore, after the inflation is stopped in step (2), the air pressure in the inner cabin is controlled in real time to remain constant; and the water pump is controlled to keep the water level in the outer cabin always lower than the required water level of the drainage pipe.

[0024] The beneficial effects of the present invention are:

[0025] (1) The present invention innovatively adopts an operating method of pumping water from the outer cabin and inflating the inner cabin. On the one hand, it makes good use of the water pressure of the external water body, which can make the repair device fit more closely with the concrete, give full play to the role of rubber waterstop, and increase the overall stability at the same time. It does not need to rely on a large amount of counterweights to make the repair device fit well with the underwater structural surface, which can reduce the overall weight and material of the repair device and save costs. On the other hand, it utilizes the effect of gas on the discharge of water from the inner cabin, which can make the inner cabin form a dry chamber, and better realize a dry working environment.

[0026] (2) The present invention adopts a spherical arch structure for the outer cabin and a hemispherical structure for the inner cabin, and the outer cabin is directly connected to the top of the inner cabin. In addition, a support plate is provided between the outer cabin and the inner cabin for supporting force transmission. The overall structure is more stable and has better load-bearing capacity.

[0027] (3) The present invention cleverly combines the water-stopping operations of pumping water from the outer compartment, inflating the inner compartment, and rubber water-blocking, which can effectively overcome the water-stopping and sealing problems under deep water conditions and solve the maintenance needs under deep water conditions, thereby effectively shortening the construction period, reducing construction costs, and ensuring the quality of repairs. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 A three-dimensional structural diagram of a double-hull underwater concrete dry chamber repair device provided by an embodiment of the present invention;

[0029] Figure 2 A top view of a double-hull underwater concrete dry chamber repair device provided by an embodiment of the present invention;

[0030] Figure 3 A cross-sectional perspective view of a double-hull underwater concrete dry chamber repair device provided by an embodiment of the present invention;

[0031] Figure 4 A front cross-sectional view of a double-hull underwater concrete dry chamber repair device provided by an embodiment of the present invention;

[0032] Figure 5 A three-dimensional structural diagram of the inner cabin and support plate of the double-hull underwater concrete dry chamber repair device provided by an embodiment of the present invention;

[0033] Figure 6 A top view of the inner cabin and support plate of the double-hull underwater concrete dry chamber repair device provided by an embodiment of the present invention;

[0034] Figure 7 This is a cross-sectional perspective view of the inner cabin and support plate in the double-hull underwater concrete dry chamber repair device provided by an embodiment of the present invention.

[0035] In the above figure: 1. Outer cabin, 2. Outer cabin skirt, 3. Outer layer VA type water-stop rubber, 4. Drain pipe, 5. Inflation pipe, 6. Outer layer Ω type water-stop rubber, 7. Inner layer support plate, 8. Outer layer support plate, 9. Inner cabin, 10. Inner cabin skirt, 11. Inner layer Ω type water-stop rubber, 12. Inner layer VA type water-stop rubber. DETAILED DESCRIPTION

[0036] In order to further understand the content, features and effects of the present invention, the following embodiments are given as examples and described in detail with reference to the accompanying drawings:

[0037] The present embodiment provides a double-hull underwater concrete dry chamber repair operation method, which uses a double-hull underwater concrete dry chamber repair device to enter the water, and after covering the underwater concrete to be repaired, first perform preliminary rubber water-stopping, then pump water from the outer chamber 1 and inflate the inner chamber 9, so that a local dry environment relative to the outside world is formed inside the double-hull underwater concrete dry chamber repair device, which is convenient for repairing the underwater concrete.

[0038] like Figures 1 to 4 As shown, the double-hull underwater concrete dry chamber repair device mainly includes an outer chamber 1 and an inner chamber 9. The outer chamber 1 is a spherical arch structure with a larger diameter, and the inner chamber 9 is a hemispherical structure with a smaller diameter. The top outer surface of the inner chamber 9 contacts and is directly fixed to the top inner surface of the outer chamber 1.

[0039] An inflation pipe 5 is provided on the top of the outer cabin 1 and the inner cabin 9. The inflation pipe 5 leads inwardly to the interior of the inner cabin 9 and outwardly passes through the outer cabin 1 to be connected to an external air compressor or air pump for inflating the inner cabin 9. The inflation pipe 5 is provided with a one-way check valve to prevent the internal gas from flowing back.

[0040] Drain pipes 4 are connected to the bulkhead of outer tank 1 and are evenly distributed around the circumference of outer tank 1. Four drain pipes 4 are preferably installed vertically. The inlet at the bottom of the drain pipe 4 extends to the bottom of outer tank 1 (and therefore is generally located outside the inner tank skirt 10). A gap exists between the pipe and the underwater concrete to ensure smooth water extraction. The outlet at the top of the drain pipe leads to the exterior of outer tank 1 and is connected to an external pump to extract water from outer tank 1. Drain pipes 4 are also equipped with one-way check valves to prevent external water from flowing back into outer tank 1.

[0041] The outer cabin 1 is in direct contact with the external water. The outer cabin skirt 2 is installed at its bottom. This is a flat plate structure that surrounds the outer cabin 1. An outer layer of Ω-type waterstop rubber 6 is installed on the bottom surface of the outer cabin skirt 2, and an outer layer of VA-type waterstop rubber 3 is installed on the outer edge of the outer cabin skirt 11. This outer layer of VA-type waterstop rubber 3, the outer layer of Ω-type waterstop rubber 6, and the outward drainage of the drain pipe 4 form the outer waterstop barrier of the repair device.

[0042] The inner chamber 7 is located within the outer chamber 1. The inner chamber 9 can enclose the underwater concrete repair area and, through inflation, squeeze out the water inside the inner chamber 9, ultimately providing a dry working environment for underwater concrete repair. The bottom of the inner chamber 7 is provided with an inner chamber skirt 10. The bottom surface of the inner chamber skirt 10 is provided with an inner layer of Ω-type waterstop rubber 11. The bottom outer edge of the inner chamber skirt 10 is provided with an inner layer of VA-type waterstop rubber 12. The inner layer of VA-type waterstop rubber 12, the inner layer of Ω-type waterstop rubber 11, and the inward inflation of the inflation tube 5 form the inner layer of the waterstop barrier of the repair device.

[0043] like Figures 5 to 7 As shown, inner and outer support plates 7, 8 are installed between the outer and inner cabins 1, 9 to support and transmit force, making the overall structure more stable and providing improved load-bearing capacity. Both inner and outer support plates 7, 8 are vertically arranged with a certain spacing between them. The inner support plate 7 is located between the bulkhead of the inner cabin 9 and the bulkhead of the outer cabin 1, while the outer support plate 8 is located between the inner cabin skirt 10 and the bulkhead of the outer cabin 1. Both inner and outer support plates 7, 8 are equipped with water / air holes to facilitate the flow of water and air within the cabins surrounded by the inner and outer support plates 7, 8.

[0044] Based on the above-mentioned repair device, the double-hull underwater concrete dry chamber repair operation method of this embodiment specifically includes the following steps:

[0045] (1) The equipment is bottomed out and the rubber is initially waterproof

[0046] The repair device enters the water and sits on the bottom around the underwater concrete where it is to be repaired, and makes the outer layer VA type water-stop rubber 3, the outer layer Ω type water-stop rubber 6, the inner layer VA type water-stop rubber 12 and the inner layer Ω type water-stop rubber 11 contact with the surface of the underwater concrete, and relies on the overall weight of the repair device in the water to complete the initial rubber compression and water-stopping work.

[0047] (2) Pumping water out of the outer cabin and inflating the inner cabin

[0048] After the outer layer VA type water-stop rubber 3, the outer layer Ω type water-stop rubber 6, the inner layer VA type water-stop rubber 12 and the inner layer Ω type water-stop rubber 11 are completely adhered to the surface of the underwater concrete and the repair device is overall stable, the water in the outer cabin 1 is pumped out to the external water body through the drain pipe 4 and the water pump. Due to the effect of water pumping, the upper part of the outer cabin gradually forms a negative pressure state relative to the external water body, so that the repair device is subjected to the pressure of the external water body; at the same time, the inner cabin 9 is slowly inflated through the inflation pipe 5, and the gas slowly enters the internal space of the inner cabin 9, pressurizing the water in the inner cabin 9 into the outer cabin 1 and pumping it away through the drain pipe 4; due to the effect of inflation, the upper part of the inner cabin 9 forms a positive pressure state, so that the repair device is subjected to the pressure of the internal water body. The lifting force of the internal gas, this process requires controlling the pumping rate to be greater than the inflation rate, ensuring that the external water pressure on the repair device is always greater than the internal gas lifting force, thereby achieving adsorption of the repair device at the damaged surface, and ensuring the underwater stability of the repair device; until the water inside the inner cabin 9 is completely drained, stop inflation, when there is little water in the outer cabin 1 and the water level is lower than the pumping requirement water level of the drain pipe 4, stop pumping; during the pumping and exhaust process, due to the action of external water pressure, the outer layer VA type water-stop rubber 3, the outer layer Ω type water-stop rubber 6, the inner layer VA type water-stop rubber 12 and the inner layer Ω type water-stop rubber 11 are compressed, the contact area with the underwater concrete is further increased, and the water-stopping effect is also improved.

[0049] Among them, the double-hull underwater concrete dry chamber repair device is overall stable, which can be judged by the displacement sensor installed on the repair device; the external water pressure on the outer cabin 1 and the gas support force on the inner cabin 9 can be identified and judged by the pressure sensor installed on the repair device; in addition, the water level in the outer cabin 1 can be judged by the water level sensor installed on the repair device.

[0050] After the above operation, a localized dry environment is created inside inner chamber 9 relative to the external water, making it easy to inspect and repair underwater concrete. During maintenance, the air pressure inside inner chamber 9 is controlled in real time to maintain a constant level. If the pressure drops, it is replenished promptly. If water seeps into outer chamber 1 and the water level inside outer chamber 1 slightly exceeds the required level for drainage pipe 4, the water pump is activated to drain the water from outer chamber 1, always keeping the water level inside outer chamber 1 below the required level for drainage pipe 4.

[0051] Although the preferred embodiments of the present invention have been described above in conjunction with the accompanying drawings, the present invention is not limited to the above-mentioned specific embodiments. The above-mentioned specific embodiments are merely illustrative and not restrictive. Under the guidance of the present invention, ordinary technicians in this field can also make many forms of specific changes without departing from the scope of protection of the invention and the claims. These all fall within the scope of protection of the present invention.

Claims

1. A double-hull underwater concrete dry chamber repair operation method, characterized in that: The method uses a double-hull underwater concrete dry chamber repair device to enter the water, and after covering the underwater concrete to be repaired, first perform preliminary rubber water stopping, then perform operations of pumping water from the outer chamber and inflating the inner chamber, so that a local dry environment relative to the outside is formed inside the double-hull underwater concrete dry chamber repair device, which is convenient for repairing the underwater concrete; The double-hull underwater concrete dry chamber repair device comprises an outer cabin and an inner cabin arranged inside the outer cabin, wherein the inner cabin can cover the underwater concrete to be repaired, and the top of the inner cabin is in contact with and directly fixed to the top of the outer cabin; The outer cabin and the top of the inner cabin are provided with an inflation pipe, which leads inward to the inner cabin and passes outward through the outer cabin to be connected to an external air compressor or air pump for inflating the inner cabin; the bulkhead of the outer cabin is connected with a drainage pipe, which is connected to an external water pump for extracting water from the outer cabin; The outer cabin bottom is provided with an outer cabin skirt, the bottom surface of the outer cabin skirt is provided with an outer layer of Ω-type water-stopping rubber, and the outer edge is provided with an outer layer of VA-type water-stopping rubber; the outer layer of VA-type water-stopping rubber, the outer layer of Ω-type water-stopping rubber, and the outward pumping of water from the drainage pipe constitute the outer layer of the water-stopping barrier of the double-hull underwater concrete dry chamber repair device; The bottom of the inner cabin is provided with an inner cabin skirt, the bottom surface of the inner cabin skirt is provided with an inner layer of Ω-type water-stop rubber, and the outer edge is provided with an inner layer of VA-type water-stop rubber; the inner layer of VA-type water-stop rubber, the inner layer of Ω-type water-stop rubber, and the inward inflation of the inflation tube constitute an inner layer of water-stop barrier; A multi-layer support plate is arranged between the outer cabin and the inner cabin for supporting force transmission, the multi-layer support plate is vertically set up around the circumference of the inner cabin and arranged in layers, and the multi-layer support plate is provided with water / air holes for water and air circulation; The steps include: (1) The double-hull underwater concrete dry chamber repair device enters the water, sits on the bottom around the underwater concrete to be repaired, and makes the outer VA-type water-stop rubber, the outer Ω-type water-stop rubber, the inner VA-type water-stop rubber and the inner Ω-type water-stop rubber contact with the surface of the underwater concrete, and relies on the self-weight of the entire repair device in the water to complete the initial rubber compression and water-stopping work; (2) After the outer VA-type waterproof rubber, the outer Ω-type waterproof rubber, the inner VA-type waterproof rubber and the inner Ω-type waterproof rubber are completely adhered to the surface of the underwater concrete and the double-hull underwater concrete dry chamber repair device is overall stable, the water in the outer chamber is pumped out to the external water body through the drainage pipe; due to the effect of pumping water, the upper part of the outer chamber gradually forms a negative pressure state relative to the external water body, so that the double-hull underwater concrete dry chamber repair device is subjected to the pressure of the external water body; at the same time, the inner chamber is inflated through the inflation pipe, and as the gas enters the internal space of the inner chamber, The water in the inner cabin is pressed against the outer cabin and pumped away through the drain pipe; due to the effect of inflation, a positive pressure state is formed in the upper part of the inner cabin, so that the double-hull underwater concrete dry chamber repair device is subjected to the top support force of the internal gas. This process requires controlling the pumping rate to be greater than the inflation rate to ensure that the external water pressure on the double-hull underwater concrete dry chamber repair device is always greater than the top support force of the internal gas, thereby achieving its adsorption at the damaged surface and ensuring its underwater stability; until the water inside the inner cabin is completely drained, stop inflation, and stop pumping when the water level in the outer cabin is lower than the required water level for pumping of the drain pipe.

2. A double-hull underwater concrete dry chamber repair operation method according to claim 1, characterized in that: The outer cabin is a spherical arch structure with a larger diameter, and the inner cabin is a hemispherical structure with a smaller diameter.

3. A double-hull underwater concrete dry chamber repair method according to claim 1, characterized in that: The inflation tube is provided with a one-way check valve to prevent the internal gas from flowing back.

4. A double-hull underwater concrete dry chamber repair method according to claim 1, characterized in that: The plurality of drain pipes are evenly arranged around the circumference of the outer chamber.

5. A double-hull underwater concrete dry chamber repair method according to claim 1, characterized in that: The drain pipe is arranged vertically, the water inlet pipe opening at the bottom end thereof extends to the bottom of the outer cabin, and the water outlet pipe opening at the top end thereof leads to the outside of the outer cabin.

6. A double-hull underwater concrete dry chamber repair method according to claim 1, characterized in that: The drain pipe is provided with a one-way check valve to prevent external water from flowing back into the outer cabin.

7. A double-hull underwater concrete dry chamber repair method according to claim 1, characterized in that: The multi-layer support plate includes an inner support plate and an outer support plate. The inner support plate is located between the bulkhead of the inner cabin and the bulkhead of the outer cabin, and the outer support plate is located between the inner cabin skirt plate and the bulkhead of the outer cabin.

8. A double-hull underwater concrete dry chamber repair method according to claim 1, characterized in that: After the inflation is stopped in step (2), the air pressure in the inner chamber is controlled in real time to remain constant; and the water pump is controlled to keep the water level in the outer chamber always lower than the required water level of the drainage pipe.

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