Self-adaptive semi-open air cushion type surge chamber and construction method thereof

Abstract

The invention provides a self-adaptive semi-open air cushion type surge chamber and a construction method thereof.The self-adaptive semi-open air cushion type surge chamber comprises a surge chamber body and a construction adit, the construction adit is of a permanent retaining structure, one end of the construction adit is connected with the surge chamber, the other end of the construction adit is communicated with an existing underground passage of an underground traffic system or the outside, and a ventilation path of the surge chamber body is formed; a blocking body is arranged at an inlet of the construction adit, the blocking body covers and seals the whole cross section of the construction adit, the blocking body is provided with at least one longitudinally-through ventilation hole channel and an airtight structure arranged at the ventilation hole channel, and the ventilation hole channel also serves as a maintenance access channel. The advantages of an open type surge chamber and an air cushion type surge chamber are integrated, meanwhile, the main defects of the open type surge chamber and the air cushion type surge chamber are avoided, the advantages of being low in construction and operation cost, flexible in arrangement, safe, reliable and easy and convenient to maintain are achieved, and a solution is provided for solving the safety guarantee problem of the long-distance pressure water conveying tunnel.

Description

Technical Field

[0001] This invention relates to the field of water conveyance tunnel engineering technology, specifically to an adaptive semi-open air cushion pressure regulating chamber and its construction method. Background Technology

[0002] In long-distance pressurized water conveyance tunnels, the inertia of the water flow can cause water hammer, resulting in a rapid increase or decrease in pressure within the pipeline during emergency opening and closing of generating units or valves. Water hammer pressure is positively correlated with the water conveyance distance; the longer the distance, the greater the damage from water hammer, potentially causing catastrophic damage to tunnels, generating units, valves, and other facilities. To reduce water hammer pressure and ensure system safety, pressure regulating chambers are typically installed in the water conveyance system. Currently, pressure regulating chambers widely used in engineering are mainly divided into two types: conventional open pressure regulating chambers and air-cushion pressure regulating chambers.

[0003] 1. Conventional Open-Type Surge Chamber: Characterized by direct communication between the water surface and the atmosphere. This type of surge chamber requires a tall vertical shaft or a long horizontal tunnel as a ventilation channel to ensure free airflow during water level fluctuations. However, this structure has extremely high requirements for terrain and geological conditions. In actual engineering, construction adits or preliminary exploration tunnels are typically used as ventilation channels. These tunnels are often no longer used for personnel passage or other purposes after construction, serving only as ventilation structures connected to the atmosphere. If site conditions limit the use of construction adits or pose operational safety risks—such as the potential for extremely high instantaneous wind speeds during operation—a dedicated ventilation tunnel must be constructed. The investment in ventilation tunnels is substantial, increasing both construction costs and subsequent operation and maintenance costs.

[0004] 2. Air-cushion pressure regulating chamber: This is a closed structure with a pre-set air chamber at the top, filled with compressed air. The compressibility of air is used to counteract water hammer pressure. This type eliminates the reliance on ventilation tunnels, offering flexible placement and freedom from terrain limitations. However, its disadvantages are equally significant: First, it requires extremely stringent airtightness of the surrounding rock and concrete lining, making construction difficult; second, during operation, air will gradually dissolve in water or leak, necessitating an expensive automatic air replenishment system (air compressor, air tank, control system, etc.) to maintain the air chamber pressure, increasing long-term operation and maintenance costs and energy consumption.

[0005] In summary, both existing surge tank technologies have certain limitations: open-type surge tanks are constrained by terrain, and their construction costs are high when there are no suitable ventilation tunnels; while air-cushion type surge tanks offer flexible layouts, they are complex systems with high operation and maintenance costs. Furthermore, the conditions for actual engineering construction vary greatly, and this contradiction inevitably affects the construction of long-distance pressurized water conveyance projects. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the first objective of this invention is to provide an adaptive semi-open air-cushion type pressure regulating chamber. This invention offers advantages such as low construction and operating costs, flexible layout, safety and reliability, and easy maintenance, providing a solution to the safety challenges of long-distance pressurized water conveyance tunnels.

[0007] In a first aspect, the present invention provides an adaptive semi-open air cushion pressure regulating chamber, comprising a pressure regulating chamber body and a construction adit. The construction adit is a permanently retained structure, with one end connected to the pressure regulating chamber and the other end connected to an existing underground passage of an underground transportation system or the outside, forming a ventilation path for the pressure regulating chamber body. A sealing body is provided at the entrance of the construction adit, covering and sealing the entire cross-section of the construction adit. At least one longitudinally penetrating ventilation channel and an airtight structure are provided on the sealing body, the ventilation channel also serving as a maintenance access channel. The airtight structure is configured to remain relaxed to allow air to pass through the ventilation channel when the air pressure in the construction adit on both sides of the sealing body is balanced; when there is an air pressure difference in the construction adit on both sides of the sealing body, the ventilation channel is sealed by the air pressure difference.

[0008] As a preferred embodiment of the present invention: the isolation grid is disposed inside the construction adit and is located between the sealing body and the entrance of the construction adit.

[0009] As a preferred technical solution of the present invention: the airtight structure is provided on both sides of the ventilation channel on the sealing body.

[0010] As a preferred embodiment of the present invention: the airtight structure includes a first airtight door structure and a second airtight door structure; The first airtight door structure is disposed on the side of the sealing body near the pressure regulating chamber body and is configured to open toward the pressure regulating chamber body; The second airtight door structure is located on the side of the sealing body near the entrance of the construction tunnel and is configured to open towards the entrance of the construction tunnel.

[0011] As a preferred embodiment of the present invention: both the first airtight door structure and the second airtight door structure include a stainless steel annular plate pad, an airtight door, and a sealing structure; the stainless steel annular plate pad is fixedly disposed on the side wall of the sealing body and is circumferentially disposed around the venting channel; the airtight door is rotatably connected to the stainless steel annular plate pad, the airtight door covers the venting channel and the side of the stainless steel annular plate pad, and the sealing structure is disposed between the airtight door and the stainless steel annular plate pad.

[0012] As a preferred embodiment of the present invention: a first hinge component is provided on the upper part of the stainless steel annular plate pad, and a second hinge component is provided on the upper part of the airtight door to cooperate with the first hinge component. A hinge rod is connected between the first hinge component and the second hinge component, and the second hinge component can rotate relative to the first hinge component about the axis of the hinge rod as the rotation center.

[0013] As a preferred embodiment of the present invention, the sealing structure is configured as an annular structure and is bonded to the side of the stainless steel annular gasket.

[0014] As a preferred technical solution of the present invention: the stainless steel annular plate pad is fixed to the sealing body by a tie rod, and the tie rod is pre-embedded in the sealing body.

[0015] As a preferred technical solution of the present invention: the pressure regulating chamber body includes an impedance hole, a pressure regulating well and a pressure regulating chamber, the pressure regulating chamber is connected to the construction adit, the bottom of the pressure regulating chamber is connected to the pressure regulating well, the bottom of the pressure regulating well is connected to the impedance hole, and the impedance hole is connected to the water conveyance tunnel.

[0016] Secondly, a second objective of the present invention is to provide a construction method for an adaptive semi-open air cushion pressure regulating chamber, comprising the following steps: S1. Perform hydraulic transition process calculations based on the layout of the water conveyance system, mainly determining the spatial dimensions of the impedance orifice, surge tank, and surge chamber. S2. When making an airtight door, the key control is the flatness of the sealing part and the center control of the door body. That is, after the door body is installed, under the condition of balanced air pressure on both sides, the airtight door and the stainless steel ring plate gasket are in light contact, and the gap width of the contact part is less than 1mm. S3. Excavate the construction adit to the top arch of the surge chamber and carry out the construction of the surge chamber body; S4. A sealing body is set at the entrance of the construction adit. Ventilation channels and stainless steel ring gaskets are reserved during the pouring of the sealing body. S5. Grouting is performed between the sealing body and the excavation face of the construction adit; S6. Install the first airtight door structure and the second airtight door structure on both sides of the sealing body respectively, and check the contact status; S7. Install an isolation grille between the sealing body and the entrance of the construction adit.

[0017] The beneficial effects provided by this invention are as follows: 1. This invention utilizes a construction adit (connected to an existing underground passage in the underground transportation system or directly connected to the outside) as the main ventilation channel, and employs a sealing structure and special ventilation features at its entrance. Compared to the large, dedicated ventilation shafts (or horizontal tunnels) required for open-type surge chambers, which have high requirements for terrain and geological conditions, this invention greatly improves the flexibility of surge chamber site selection, avoids the huge civil engineering investment required to construct dedicated ventilation tunnels when construction adits cannot be used, and significantly reduces project costs.

[0018] 2. This invention makes the most of the "abandoned" facilities inherent in engineering construction, such as construction adits, giving them new operational functions, realizing comprehensive utilization of resources, and conforming to the engineering concept of green and sustainable development. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 A plan view of the semi-open air cushion pressure regulating chamber provided in an embodiment of the present invention; Figure 2 for Figure 1 AA-direction cross section; Figure 3 This is a partial enlarged view of the sealing body provided in an embodiment of the present invention; Figure 4 A schematic diagram of the hinge connection between the stainless steel annular plate gasket and the airtight door provided in an embodiment of the present invention; Figure 5 A plan view of the stainless steel annular plate pad provided in an embodiment of the present invention; Figure 6 A plan view of an airtight door provided in an embodiment of the present invention; Figure 7 A plan view of the hinge rod provided in an embodiment of the present invention.

[0021] Reference numerals: 1. Pressure regulating chamber; 2. Pressure regulating well; 3. Impedance hole; 4. Construction adit; 5. Sealing body; 6. Isolation grid; 7. Reinforced concrete lining; 8. First airtight door structure; 9. Second airtight door structure; 10. Stainless steel annular plate gasket; 11. Tie rod; 12. First hinge component; 13. Second hinge component; 14. Hinge rod; 15. Bolt head; 16. Nut; 18. Construction adit entrance; 19. Ventilation duct; 20. Airtight door; 21. Sealing structure. Detailed Implementation

[0022] To enable those skilled in the art to better understand the technical solutions of the present invention, preferred embodiments of the present invention are described below in conjunction with specific examples. However, it should be understood that the accompanying drawings are for illustrative purposes only and should not be construed as limiting the present invention. For better illustration of this embodiment, some components in the drawings may be omitted, enlarged, or reduced, and do not represent the actual dimensions of the product. It is understandable that some well-known structures and their descriptions may be omitted in the drawings for those skilled in the art. The positional relationships described in the drawings are for illustrative purposes only and should not be construed as limiting the present invention.

[0023] The present invention will be further described below with reference to the accompanying drawings and embodiments, but this should not be construed as limiting the present invention.

[0024] like Figure 1 and Figure 2 As shown, an adaptive semi-open air cushion pressure regulating chamber includes a pressure regulating chamber body and a construction adit 4. The construction adit 4 is a permanently retained structure, with one end connected to the pressure regulating chamber 1 and the other end connected to an existing underground passage of the underground transportation system or the outside, forming the ventilation path of the pressure regulating chamber body. The underground passage can be a traffic tunnel, etc. A sealing body 5 is provided at the entrance of the construction adit 4. The sealing body 5 covers and seals the entire cross-section of the construction adit 4. A joint grouting is provided between the sealing body 5 and the excavation face of the construction adit 4 to prevent air leakage at the contact point when the air pressure is unbalanced. The sealing body 5 is provided with at least one longitudinally penetrating vent 19 and an airtight structure disposed at the vent 19. The vent 19 also serves as a maintenance access passage, and the diameter of the vent 19 is sufficient for personnel passage. The airtight structure is configured to remain relaxed to allow air to pass through the vent 19 when the air pressure in the construction adits 4 on both sides of the sealing body 5 is balanced. When there is an air pressure difference in the construction adits 4 on both sides of the sealing body 5, the vent 19 is sealed by the air pressure difference, and the greater the air pressure difference, the better the sealing performance.

[0025] The isolation grille 6 is installed inside the construction adit 4 and is located between the sealing body 5 and the construction adit entrance 18. The main function of the isolation grille 6 is to prevent personnel from accidentally entering and approaching the sealed door, thus avoiding unnecessary injury.

[0026] The airtight structure is provided on both sides of the vent 19 on the sealing body 5.

[0027] like Figure 3 The airtight structure shown includes a first airtight door structure 8 and a second airtight door structure 9. In order to improve the reliability of the airtight structure function, the two sides of the sealing body 5 must remain upright.

[0028] The first airtight door structure 8 is disposed on the side of the sealing body 5 near the pressure regulating chamber body and is configured to open toward the pressure regulating chamber body; The second airtight door structure 9 is disposed on the side of the sealing body 5 near the entrance 18 of the construction branch tunnel, and is configured to open in the direction of the entrance 18 of the construction branch tunnel.

[0029] The first airtight door structure 8 and the second airtight door structure 9 are arranged symmetrically.

[0030] like Figure 4 , 5 As shown in Figures 6 and 7, both the first airtight door structure 8 and the second airtight door structure 9 include a stainless steel annular plate pad 10, an airtight door 20, and a sealing structure 21. The stainless steel annular plate pad 10 is fixedly disposed on the side wall of the sealing body 5 and is circumferentially disposed around the venting channel 19. The airtight door 20 is rotatably connected to the stainless steel annular plate pad 10, and the airtight door 20 covers the venting channel 19 and the side of the stainless steel annular plate pad 10. The sealing structure 21 is disposed between the airtight door 20 and the stainless steel annular plate pad 10.

[0031] The upper part of the stainless steel annular plate pad 10 is provided with a first hinge component 12, which is specifically a perforated steel plate and is symmetrically arranged on the upper part of the stainless steel annular plate pad 10. The upper part of the airtight door 20 is provided with a second hinge component 13 that cooperates with the first hinge component 12. Specifically, the second hinge component 13 is a perforated rod extending outward from the top of the airtight door and the number of rods provided matches the number of the first hinge components 12. The first hinge component 12 and the second hinge component 13 are connected by a hinge rod 14. The second hinge component 13 can rotate relative to the first hinge component 12 with the axis of the hinge rod 14 as the rotation center.

[0032] The sealing structure 21 is annular and is bonded to the side of the stainless steel annular gasket 10. The sealing structure 21 is made of rubber, specifically a rubber sealing ring, and is bonded to the stainless steel annular gasket 10 using a room temperature vulcanizing rubber adhesive.

[0033] When installing the airtight door, align the through hole of the second hinge component 13 with the through hole of the first hinge component 12, insert the hinge rod 14, and tighten it with the nut 16. The through holes of the first hinge component 12 and the second hinge component 13 have the same diameter. The airtight door is hinged to the upper part of the stainless steel annular plate pad 10 and is sealed by its own weight. When the air pressure on both sides of the sealing body 5 is basically the same, the two airtight doors and the sealing structure 21 are in a relaxed state, and air can circulate between them. However, when the water level in the pressure regulating well 2 rises due to the water hammer, the water squeezes the air in the pressure regulating chamber 1 and the pressure regulating well 2 and pushes it outward. Under the action of the flowing air, the airtight door of the first airtight door structure 8 squeezes the rubber sealing ring, and the air circulation gradually dissipates. When the water level falls, similarly, the airtight door of the second airtight door structure 9 squeezes the rubber sealing ring, and the air circulation gradually dissipates, thus forming a relatively sealed space.

[0034] The stainless steel annular plate pad 10 is fixed to the sealing body 5 by a tie rod 11, which is pre-embedded in the sealing body 5.

[0035] In this embodiment, to ensure the reliability of the airtight door 20, it is made of a relatively lightweight alloy and uses a spherical shape to convert the air pressure difference into compressive stress within the door body, achieving a lightweight and high-strength function. Simultaneously, the door design aims to control its center of gravity; when the air pressure is balanced, the door body and the rubber sealing ring are in a relaxed and closed state.

[0036] like Figure 7 As shown, the hinge rod 14 is made of a round rod of corrosion-resistant material such as stainless steel. Its diameter is slightly smaller than the through hole of the first hinge component 12 and the second hinge component 13. One end is threaded and sealed with a nut 16, and the other end is a bolt head 15.

[0037] While this invention possesses the advantages of an air-cushion pressure regulating chamber under extreme operating conditions, its air chamber (the cavity at the top of the pressure regulating chamber) is indirectly connected to the atmosphere through a pressure differential adaptive airtight door. During normal operation and minor fluctuations in water level, air can be freely replenished or discharged without maintaining a constant high pressure. Therefore, it completely eliminates the need for an expensive and complex set of air replenishment equipment, such as an automatic air compressor, a large air storage tank, and a pressure sensing and control system, which are essential for air-cushion pressure regulating chambers. This fundamentally eliminates the purchase cost, power consumption, and long-term maintenance costs of this equipment, achieving extremely low operating energy consumption.

[0038] The pressure regulating chamber body includes an impedance hole 3, a pressure regulating well 2, and a pressure regulating chamber 1. The pressure regulating chamber 1 is connected to the construction adit 4. The bottom of the pressure regulating chamber 1 is connected to the pressure regulating well 2. The bottom of the pressure regulating well 2 is connected to the impedance hole 3. The impedance hole 3 is connected to the water conveyance tunnel. The main purpose is to increase the damping of the pressure regulation and reduce the surge height under the action of water hammer.

[0039] In this embodiment, a retaining wall is installed at the location of the construction adit 4 near the surge chamber 1 to increase the water capacity of the surge chamber 1. A ladder is also installed to climb over the retaining wall as a passage for later maintenance.

[0040] Impedance hole 3, surge tank 2, surge chamber 1, and construction adit 4 are supported according to the stability of the rock mass; permanent reinforced concrete lining 7 is added to impedance hole 3, surge tank 2, and surge chamber 1; consolidation grouting is installed in impedance hole 3 and surge tank 2.

[0041] This invention also provides a construction method for an adaptive semi-open air cushion pressure regulating chamber, comprising the following steps: S1. Perform hydraulic transition process calculations based on the layout of the water conveyance system, mainly determining the spatial dimensions of impedance orifice 3, surge tank 2, and surge chamber 1; the key point of this calculation is to consider the influence of air pressure fluctuations under airtight conditions.

[0042] S2. Make the airtight door 20, focusing on controlling the flatness of the closed part and the center control of the door body. That is, ensure that after the door body is installed, the airtight door 20 and the stainless steel annular plate pad 10 are in light contact with each other under the condition of balanced air pressure on both sides, and the gap width of the contact part is less than 1mm. S3. Excavate the construction adit 4 to the top arch of the surge chamber 1, and carry out the construction of the surge chamber body; Specifically, the construction of the pressure regulating chamber includes: S3.1 Excavate pressure regulating chamber 1 and complete shotcrete and anchor support; S3.2. The pressure regulating well 2 and the impedance hole 3 are excavated using the pilot well method, and shotcrete and anchor support are carried out during the excavation process. S3.3. Impedance hole 3 and pressure regulating well 2 are poured sequentially using a sliding membrane. Steel plate lining and consolidation grouting are added as needed according to the structural design. The structural parts involved in this step are set according to the structural requirements of the open pressure regulating chamber 11.

[0043] S4. A sealing body 5 is installed at the entrance of the construction adit 4. During the pouring of the sealing body 5, a ventilation channel 19 and a stainless steel annular plate gasket 10 are reserved. The sealing body 5 is arranged as far away from the pressure regulating chamber 1 as possible to make full use of the volume of the cavity of the construction adit 4 and reduce the change of air pressure in the pressure regulating chamber 1.

[0044] S5. Grouting is installed between the excavation face of the sealing body 5 and the construction adit 4; S6. Install the first airtight door structure 8 and the second airtight door structure 9 on both sides of the sealing body 5 respectively, and check the contact status. S7. An isolation grid 6 shall be installed at a distance of not less than 10m from the entrance of the sealing body 5 and the construction adit 4.

[0045] This invention employs an adaptive dual-mode operation, ensuring high safety and reliability. The core of this invention lies in its "dual-mode" operation mechanism: Normal mode (ventilation mode): When the air pressure inside and outside the pressure regulating chamber is balanced, the two airtight doors are in a relaxed state, and the construction support tunnel serves as a smooth air passage, ensuring that air can freely enter and exit. The pressure regulating chamber exhibits open characteristics and has the best operating efficiency.

[0046] Transient mode (closed pressure-holding mode): When extreme conditions such as water hammer occur, and a sudden negative or positive pressure impact is generated in the pressure regulating chamber, the two airtight doors are quickly compressed and closed under the action of a huge air pressure difference, and the characteristic that "the greater the air pressure difference, the better the sealing performance" is utilized to achieve efficient sealing. At this time, a temporary air cushion chamber is formed at the top of the pressure regulating chamber, which uses the compressibility and elasticity of air to absorb and reduce the water hammer pressure, demonstrating the advantages of the air cushion type and effectively protecting the safety of the tunnel and unit equipment.

[0047] This invention has lower requirements for the airtightness of the tunnel, simplifying construction and reducing difficulty. Compared with the stringent airtightness requirements of traditional air-cushion surge chambers for concrete lining and surrounding rock, this invention only requires high-precision sealing on the local sealing body at the entrance of the construction adit. The surge chamber body and most of the tunnel do not require special airtightness treatment; only reinforced concrete lining and grouting as required by conventional hydraulic tunnels are needed, greatly simplifying the construction process and reducing technical difficulty and construction risks.

[0048] This invention features a simple structure, requires no external power, and is easy to maintain. The core of the entire ventilation and sealing system—the airtight structure—is a purely mechanical structure, requiring no electric drive or complex control logic. It achieves adaptive opening and closing based on physical principles, fundamentally avoiding the risk of electrical failures and ensuring robust durability. Simultaneously, the ventilation channels of this invention also serve as maintenance access passages, and are equipped with ladders and isolation grilles, providing a safe and convenient passage for later inspection and maintenance, resulting in minimal maintenance workload and low costs.

[0049] Based on the description and accompanying drawings of this invention, those skilled in the art can readily manufacture or use an adaptive semi-open air cushion pressure regulating chamber and its construction method, and can achieve the positive effects described in this invention.

[0050] Unless otherwise specified, in this invention, terms such as "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe orientation or positional relationships in this invention are for illustrative purposes only and should not be construed as limiting this invention. For those skilled in the art, the specific meaning of the above terms can be understood in conjunction with the accompanying drawings and according to the specific circumstances.

[0051] Unless otherwise explicitly specified and limited, the terms "set up," "connected," and "linked" in this invention should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0052] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications or equivalent changes made to the above embodiments based on the technical essence of the present invention shall fall within the protection scope of the present invention.

Claims

1. An adaptive semi-open air cushion pressure regulating chamber, characterized in that: The system includes a pressure regulating chamber body and a construction adit, which is a permanently retained structure. One end of the construction adit connects to the pressure regulating chamber, and the other end connects to an existing underground passage of the underground transportation system or the outside, forming the ventilation path of the pressure regulating chamber body. A sealing body is installed at the entrance of the construction adit, covering and sealing the entire cross-section of the construction adit. The sealing body is provided with at least one longitudinally penetrating ventilation channel and an airtight structure located at the ventilation channel. The ventilation channel also serves as a maintenance access channel. The airtight structure is configured to remain relaxed to allow air to pass through the ventilation channel when the air pressure in the construction adit on both sides of the sealing body is balanced. When there is an air pressure difference in the construction adit on both sides of the sealing body, the ventilation channel is sealed by the air pressure difference.

2. The adaptive semi-open air cushion pressure regulating chamber according to claim 1, characterized in that: The isolation grille is installed inside the construction adit and is located between the sealing body and the entrance of the construction adit.

3. The adaptive semi-open air cushion pressure regulating chamber according to claim 1, characterized in that: The airtight structure is provided on both sides of the venting channel on the sealing body.

4. The adaptive semi-open air cushion pressure regulating chamber according to claim 3, characterized in that: The airtight structure includes a first airtight door structure and a second airtight door structure; The first airtight door structure is disposed on the side of the sealing body near the pressure regulating chamber body and is configured to open toward the pressure regulating chamber body; The second airtight door structure is located on the side of the sealing body near the entrance of the construction tunnel and is configured to open towards the entrance of the construction tunnel.

5. The adaptive semi-open air cushion pressure regulating chamber according to claim 4, characterized in that: Both the first and second airtight door structures include a stainless steel annular plate pad, an airtight door, and a sealing structure; the stainless steel annular plate pad is fixedly disposed on the side wall of the sealing body and is circumferentially disposed around the venting channel; the airtight door is rotatably connected to the stainless steel annular plate pad, the airtight door covers the venting channel and the side of the stainless steel annular plate pad, and the sealing structure is disposed between the airtight door and the stainless steel annular plate pad.

6. The adaptive semi-open air cushion pressure regulating chamber according to claim 5, characterized in that: The upper part of the stainless steel annular plate pad is provided with a first hinge component, and the upper part of the airtight door is provided with a second hinge component that cooperates with the first hinge component. A hinge rod is connected between the first hinge component and the second hinge component, and the second hinge component can rotate relative to the first hinge component about the axis of the hinge rod as the rotation center.

7. The adaptive semi-open air cushion pressure regulating chamber according to claim 5, characterized in that: The sealing structure is annular and is bonded to the side of the stainless steel annular gasket.

8. The adaptive semi-open air cushion pressure regulating chamber according to claim 5, characterized in that: The stainless steel annular plate gasket is fixed to the sealing body by a tie rod, which is pre-embedded in the sealing body.

9. The adaptive semi-open air cushion pressure regulating chamber according to claim 1, characterized in that: The pressure regulating chamber body includes an impedance hole, a pressure regulating well, and a pressure regulating chamber. The pressure regulating chamber is connected to the construction adit. The bottom of the pressure regulating chamber is connected to the pressure regulating well. The bottom of the pressure regulating well is connected to the impedance hole. The impedance hole is connected to the water conveyance tunnel.

10. A construction method for an adaptive semi-open air cushion pressure regulating chamber, characterized in that, The construction of the semi-open air cushion pressure regulating chamber as described in claims 1-9 includes the following steps: S1. Perform hydraulic transition process calculations based on the layout of the water conveyance system, mainly determining the spatial dimensions of the impedance orifice, surge tank, and surge chamber. S2. When making an airtight door, the key control is the flatness of the sealing part and the center control of the door body. That is, after the door body is installed, under the condition of balanced air pressure on both sides, the airtight door and the stainless steel ring plate gasket are in light contact, and the gap width of the contact part is less than 1mm. S3. Excavate the construction adit to the top arch of the surge chamber and carry out the construction of the surge chamber body; S4. A sealing body is set at the entrance of the construction adit. Ventilation channels and stainless steel ring gaskets are reserved during the pouring of the sealing body. S5. Grouting is performed between the sealing body and the excavation face of the construction adit; S6. Install the first airtight door structure and the second airtight door structure on both sides of the sealing body respectively, and check the contact status; S7. Install an isolation grille between the sealing body and the entrance of the construction adit.

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