A method for improving ventilation of a long tunnel

Abstract

The application discloses a method for improving ventilation of a special long tunnel, and relates to the technical field of tunnel construction, which comprises the following steps: S1, reserving a hole; S2, fixing and assembling parts; S3, intermittent ventilation; S4, high-power ventilation; and S5, exhaust gas discharge. The application can change the suction points by using the suction box to realize multi-type ventilation and exhaust, so that the through pipe does not need to be provided with branch-shaped auxiliary pipes for auxiliary ventilation, which effectively improves the cost and convenience of burying the through pipe in the shaft. In addition, the partition plate divides the through pipe into two independent spaces, the left end of which is ventilated, and the right end of which is exhausted, so that the exhaust device can realize the harmful exhaust emission by using a single through pipe. The working suction box can send the air in the through pipe into the gas collecting box through the connecting pipe, and then the fresh air is sent into the tunnel through the air outlet of the ventilation pipe. By using the high-power suction of the suction box, sufficient ventilation can be ensured when the tunnel is busy.

Description

Technical Field

[0001] This invention relates to the field of tunnel construction technology, specifically to a method for improving ventilation in extra-long tunnels. Background Technology

[0002] With the development of railway construction, the number of long and extra-long tunnels has gradually increased. Ventilation during the construction of long and extra-long tunnels has become a key problem. Conventional forced ventilation and tunnel ventilation have long ventilation distances and large losses in air volume and air velocity, making it difficult to meet the requirements of long tunnels. Therefore, in long tunnels today, the use of vertical shaft ventilation that connects the tunnel roof to the mountain has become the main method for extra-long tunnels.

[0003] For example, application number 201811097079.9 discloses a ventilation method for constructing long, high-wattage tunnels. Ventilation is divided into two stages based on the construction progress. In the first stage, before the ventilation shaft is completed, forced ventilation is used in the tunnel's entrance and exit areas and the inclined shaft area in the middle of the tunnel. In the second stage, after the ventilation shaft is completed, the ventilation methods in the tunnel's entrance and exit areas remain unchanged, but jet fans are added inside the tunnel to enhance return air according to the construction progress. The inclined shaft area in the middle of the tunnel adopts an innovative ventilation method of intake ventilation from the vertical shaft and exhaust ventilation from the inclined shaft. Jet fans are added inside the tunnel according to the construction progress at both ends of the inclined shaft area, allowing polluted air to be continuously discharged from the inclined shaft via the jet fans. This invention, through the reasonable combination of two ventilation modes in different stages and work areas, not only improves the ventilation effect but also significantly reduces construction costs. Simultaneously, by setting up wind-powered and gas-powered interlocking systems, the personal safety of construction personnel is ensured.

[0004] The ventilation methods for extra-long tunnels similar to those described in the above application still have the following shortcomings: Existing vertical shaft ventilation ducts require a large number of branch pipes at their external ends to achieve effective ventilation. However, the difficulty of burying branch pipes in vertical shafts is generally high, and large-diameter vertical shafts need to be dug for effective burial. This will affect the structural stability of the tunnel. In addition, the ventilation range of current ventilation methods for extra-long tunnels is small, which leads to an increase in the number of vertical shafts dug in extra-long tunnels, which will further increase ventilation costs.

[0005] Therefore, in view of this, we studied and improved the existing structure and its shortcomings, and proposed a method to improve ventilation in extra-long tunnels. Summary of the Invention

[0006] The purpose of this invention is to provide a method for improving ventilation in extra-long tunnels, so as to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a method for improving ventilation in extra-long tunnels, comprising the following steps: S1, Opening of the reserved tunnel: A vertical shaft leading directly to the top of the tunnel is opened outside the mountain, and a placement trough is opened inside the top of the tunnel; S2. Component fixing assembly: Insert the inlet pipe into the vertical shaft, ensuring the top of the inlet pipe protrudes outside the mountain and the end of the inlet pipe extends into the installation trench. Fix the motor to the inner wall of the installation trench. Align the docking seats at both ends of the external air extraction box with the end of the inlet pipe and the connecting pipe for connection. After completing the above operations, fix the support plate to the bottom inner wall of the installation trench to complete the connection between the air extraction box and the inlet pipe. Fix the air collection box to the bottom of the support plate and connect the air collection box to the connecting pipe. Insert the ventilation pipe into both ends of the external air collection box and fix the ventilation pipe to the top of the tunnel. S3, Intermittent ventilation: When the air intake fan operates, it blows air from outside the tunnel into the inlet pipe. At the same time, the air extraction box operates, evacuating the air inside the air collection box through the connecting pipe, creating a vacuum in the air collection box. After the air inside the air collection box is evacuated, the air extraction box stops operating and connects the inlet pipe to the connecting pipe. At this time, the valve outside the connecting pipe opens, and the air in the inlet pipe rushes into the air collection box due to the air pressure difference. Subsequently, the valve outside the ventilation pipe opens, and fresh air from the air collection box enters the ventilation pipe and enters the tunnel through the air outlet. S4, High-power ventilation; The motor drives the air extraction box to rotate, so that the positions of the two suction ports of the air extraction box are reversed. The air intake fan works to blow air from outside the tunnel into the inside of the inlet pipe. At this time, the air extraction box works and can send the air in the inlet pipe into the air collection box through the connecting pipe. Then the ventilation pipe sends fresh air into the tunnel through the air outlet. S5. Exhaust gas discharge: The motor drives the air extraction box to rotate, so that the air extraction port of the air extraction box faces the connecting pipe. At the same time, the air extraction box connects the connecting pipe and the exhaust pipe. When the air extraction box is working, the exhaust gas in the tunnel can be drawn into the ventilation pipe through the air outlet, and then enter the connecting pipe through the air collection box. Subsequently, the exhaust gas can be discharged into the inlet pipe through the exhaust pipe and discharged from the exhaust port.

[0008] In step S1, the vertical shaft and the placement trench are interconnected.

[0009] In step S2, during the process of connecting the docking seat with the inlet pipe and the connecting pipe, the electric actuator drives the extension pipe to move within the fixed pipe, so that the docking seat extends and connects with the inlet pipe and the connecting pipe.

[0010] In step S2, the motor and the vacuum box are integrated into one unit, and the motor is fixed to the inner wall of the mounting slot by locking bolts.

[0011] In step S3, when the extraction box extracts air from the collection box, the valve outside the ventilation pipe is closed.

[0012] In step S3, during the process of the air collection box ventilating the ventilation pipe, the valves outside the ventilation pipe at each point on the outer end of the air collection box will open and close intermittently in sequence.

[0013] In step S4, before the motor drives the vacuum box to rotate, the electric push rod operates to move the extension tube within the fixed tube, causing the docking seat to separate from the inlet tube and the connecting tube.

[0014] In step S4, when the air collection box supplies air to the ventilation pipes at each location, all valves outside the ventilation pipes are in the open state.

[0015] In step S4, when the extraction box rotates, the bearing swivel can offset the torque of the extraction box rotation by rotating, so that the exhaust pipe is always at a fixed position.

[0016] In step S5, the partition divides the inlet pipe into two independent spaces, left and right, with air flowing through the left end and exhausting from the right end.

[0017] This invention provides a method for improving ventilation in extra-long tunnels, which has the following beneficial effects: 1. In this invention, the air intake fan blows air from outside the tunnel into the inlet pipe. Simultaneously, the air extraction box operates, evacuating the air inside the air collection box through the connecting pipe, creating a vacuum. After the air inside the air collection box is evacuated, the air extraction box stops operating, and the inlet pipe is connected to the connecting pipe. At this time, the valve outside the connecting pipe opens, and air in the inlet pipe rushes into the air collection box due to the air pressure difference. Subsequently, the valve outside the ventilation pipe opens, and fresh air from the air collection box enters the ventilation pipe and enters the tunnel through the air outlet. Intermittent ventilation can be used when the workload in the tunnel is small and large-scale ventilation is not required, which can greatly reduce the energy consumption of the ventilation device. In addition, by using the siphon effect after the air collection box is vacuumed to accelerate the air circulation in the inlet pipe, the amount of outside air entering during intermittent ventilation can be effectively guaranteed.

[0018] 2. During the ventilation process from the air collection box to the ventilation pipe, the valves at various points on the outer end of the air collection box will open and close intermittently in sequence. This ensures that the air collection box injects air into only one ventilation pipe at a time. The length of each ventilation pipe at the outer end of the air collection box is different, and the air outlet points on the surface of each ventilation pipe are also different. This allows the ventilation pipe to spread air to a relatively far range within the tunnel, centered on the air collection box. This effectively expands the air distribution range. In addition, injecting air into only one ventilation pipe at a time also effectively ensures that the air pressure can spread the air to a relatively far location.

[0019] 3. The electric actuator of this invention drives the extension tube to move within the fixed tube, causing the docking seat to separate from the inlet pipe and the connecting pipe. At this time, the motor drives the air extraction box to rotate, causing the positions of the two suction ports of the air extraction box to be reversed. The air intake fan works, blowing air from outside the tunnel into the interior of the inlet pipe. At this time, the air extraction box works, which can send the air in the inlet pipe into the air collection box through the connecting pipe. Then, the ventilation pipe sends fresh air into the tunnel through the air outlet. By using the high-power air extraction of the air extraction box, sufficient ventilation can be ensured when working in the tunnel.

[0020] 4. The present invention uses a motor to drive the air extraction box to rotate, so that the air extraction port of the air extraction box faces the connecting pipe. At the same time, the air extraction box connects the connecting pipe and the exhaust pipe. When the air extraction box is working, the exhaust gas in the tunnel can be drawn into the ventilation pipe through the air outlet and enter the connecting pipe through the air collection box. Then the exhaust gas can be discharged into the inlet pipe through the exhaust pipe and discharged from the exhaust port. This allows the ventilation device to effectively absorb and discharge the harmful gases when a large amount of harmful gases are released during tunnel construction. Thanks to the large ventilation range of the ventilation device, the absorption range of harmful gases is also expanded.

[0021] 5. This invention uses an air extraction box to change the suction point to achieve multiple types of ventilation and exhaust. It eliminates the need for branch-shaped secondary pipes for auxiliary ventilation in the inlet pipe, which effectively improves the cost and convenience of burying the inlet pipe in the shaft. In addition, the partition divides the inlet pipe into two independent spaces, with air entering at the left end and exhausting at the right end. This allows the exhaust device to achieve the process of emitting harmful exhaust gases using only a single inlet pipe. Attached Figure Description

[0022] Figure 1 A frontal view of the overall structure of a ventilation method for extra-long tunnels; Figure 2 for Figure 1 Enlarged structural diagram at point A in the middle; Figure 3 This is a schematic diagram of the longitudinal section of the ventilation duct. Figure 4 This is a schematic diagram of the air collection box viewed from below. Detailed Implementation

[0023] Please see Figure 1-4 The present invention provides a technical solution: a method for improving ventilation in extra-long tunnels, comprising the following steps: S1, Opening of the reserved tunnel: A vertical shaft leading directly to the top of the tunnel is opened outside the mountain, and a placement trough connected to the vertical shaft is opened inside the top of the tunnel.

[0024] S2. Component fixing assembly: Insert the inlet pipe into the vertical shaft, ensuring the top of the inlet pipe protrudes outside the mountain and the end of the inlet pipe extends into the installation trench. Secure the motor to the inner wall of the installation trench using fixing bolts. Align the docking seats at both ends of the external air extraction box with the inlet pipe and the docking pipe, respectively. The electric actuator moves the extension pipe within the fixed pipe, extending the docking seats and connecting them with the inlet pipe and the docking pipe. After completing the above operations, fix the support plate to the bottom inner wall of the installation trench, completing the connection between the air extraction box and the inlet pipe. Fix the air collection box to the bottom of the support plate and connect it with the docking pipe. Insert the ventilation pipe into both ends of the external air collection box and fix it to the tunnel roof.

[0025] S3, Intermittent ventilation: When the intake fan operates, it blows air from outside the tunnel into the intake pipe. Simultaneously, the extraction box operates, evacuating the air from the collection box via the connecting pipe, creating a vacuum. Once the air in the collection box is evacuated, the extraction box stops operating, and the intake pipe is connected to the connecting pipe. At this point, the valve outside the connecting pipe opens, allowing air from the intake pipe to rush into the collection box due to the pressure difference. Subsequently, the valve outside the ventilation duct opens, allowing fresh air from the collection box to enter the ventilation duct and then into the tunnel through the outlet. Intermittent ventilation can be used when the workload in the tunnel is low and extensive ventilation is not required. This significantly reduces the energy consumption of the ventilation system. Furthermore, by using a vacuum opening mechanism in the collection box… The siphon effect after opening accelerates the airflow into the pipe, effectively ensuring the amount of outside air entering during intermittent ventilation. During the ventilation process from the air collection box to the ventilation pipe, the valves at various points on the outside of the air collection box will open and close intermittently in sequence. This ensures that the air collection box injects air into only one ventilation pipe at a time. The length of each ventilation pipe at the outside of the air collection box is different, and the air outlet points on the surface of each ventilation pipe are also different. This allows the ventilation pipe to spread air to a relatively far range within the tunnel, centered on the air collection box. This effectively expands the air distribution range. In addition, injecting air into only one ventilation pipe at a time also effectively ensures that the air pressure can spread the air to a relatively far location.

[0026] S4, High-power ventilation; The electric actuator moves the extension tube within the fixed tube, separating the docking seat from the inlet and connecting pipes. At this time, the motor drives the extraction box to rotate, reversing the positions of the two suction ports. The air intake fan then blows air from outside the tunnel into the inlet pipe. The extraction box then draws air from the inlet pipe into the air collection box through the connecting pipe. Subsequently, the ventilation pipe delivers fresh air into the tunnel through the outlet. By using a high-power extraction box, sufficient ventilation is ensured during busy work inside the tunnel.

[0027] S5. Exhaust gas discharge: The motor drives the extraction box to rotate, positioning its extraction port towards the connecting pipe. Simultaneously, the extraction box connects the connecting pipe to the exhaust pipe. When the extraction box operates, exhaust gases from the tunnel are drawn into the ventilation duct through the outlet and then into the connecting pipe via the gas collection box. The exhaust gases are then discharged through the exhaust pipe into the inlet pipe and out of the exhaust port. This allows the ventilation system to effectively absorb and expel large amounts of harmful gases released during tunnel construction. Thanks to the large ventilation range of the ventilation system, the absorption range of harmful gases is also expanded. By using the extraction box to vary the extraction point, multiple types of ventilation and exhaust can be achieved. The inlet pipe does not require branch-like secondary pipes for auxiliary ventilation, effectively improving the cost and convenience of burying the inlet pipe in the shaft. Furthermore, a partition divides the inlet pipe into two independent spaces, with air entering from the left end and exhausting from the right end. This allows the exhaust system to discharge harmful gases using only a single inlet pipe.

[0028] In summary, this method for improving ventilation in extra-long tunnels involves first constructing a vertical shaft outside the mountain that extends directly to the tunnel roof, and then constructing a placement trough connected to the vertical shaft on the inner side of the tunnel roof. Then, insert the inlet pipe into the vertical shaft, so that the top of the inlet pipe protrudes outside the mountain and the end of the inlet pipe extends into the installation groove. Fix the motor to the inner wall of the installation groove with fixing bolts. Then, align the docking seats at both ends of the outside of the air extraction box with the inlet pipe and the docking pipe respectively. The electric actuator drives the extension pipe to move inside the fixed pipe, so that the docking seats extend and connect with the inlet pipe and the docking pipe. After completing the above operations, fix the support plate to the bottom inner wall of the installation groove to complete the connection between the air extraction box and the inlet pipe. Fix the air collection box to the bottom of the support plate and connect the air collection box with the docking pipe. Insert the ventilation pipe into both ends of the outside of the air collection box and fix the ventilation pipe to the top of the tunnel. Next, the air intake fan operates, blowing air from outside the tunnel into the inlet pipe. Simultaneously, the air extraction box operates, evacuating the air inside the air collection box through the connecting pipe, creating a vacuum in the air collection box. After the air inside the air collection box is evacuated, the air extraction box stops operating, and the inlet pipe is connected to the connecting pipe. At this time, the valve outside the connecting pipe opens, and the air in the inlet pipe rushes into the air collection box due to the air pressure difference. Subsequently, the valve outside the ventilation pipe opens, and fresh air from the air collection box enters the ventilation pipe and enters the tunnel through the air outlet. Intermittent ventilation can be used when the workload in the tunnel is small and large-scale ventilation is not required. This can greatly reduce the energy consumption of the ventilation device. In addition, by using the siphon effect after the air collection box is opened to create a vacuum, the air circulation in the inlet pipe is accelerated, which can effectively ensure the amount of outside air entering during intermittent ventilation. Subsequently, during the process of the air collection box ventilating the ventilation pipes, the valves at various points on the outside of the ventilation pipes at the outer end of the air collection box will open and close intermittently in sequence. This ensures that the air collection box injects air into only one ventilation pipe at a time. The length of each ventilation pipe at the outer end of the air collection box is different, and the air outlet points on the surface of each ventilation pipe are also different. This allows the ventilation pipes to spread air to a relatively far range within the tunnel, centered on the air collection box. This effectively expands the air distribution range. In addition, injecting air into only one ventilation pipe at a time also effectively ensures that the air pressure can spread the air to a relatively far location. Then, the electric actuator drives the extension tube to move within the fixed tube, separating the docking seat from the inlet pipe and the connecting pipe. At this time, the motor drives the air extraction box to rotate, causing the positions of the two suction ports of the air extraction box to be reversed. The air intake fan works, blowing air from outside the tunnel into the inside of the inlet pipe. At this time, the air extraction box works, sending the air in the inlet pipe into the air collection box through the connecting pipe. Then, the ventilation pipe sends fresh air into the tunnel through the air outlet. By using the high-power air extraction of the air extraction box, sufficient ventilation can be ensured when working in the tunnel. Finally, the motor drives the extraction box to rotate, so that the extraction port of the extraction box faces the connecting pipe. At the same time, the extraction box connects the connecting pipe and the exhaust pipe. When the extraction box is working, the exhaust gas in the tunnel can be drawn into the ventilation pipe through the air outlet and enter the connecting pipe through the air collection box. Then the exhaust gas can be discharged into the inlet pipe through the exhaust pipe and discharged from the exhaust port. This allows the ventilation device to effectively absorb and discharge the harmful gases when a large amount of harmful gases are released during tunnel construction. Thanks to the large ventilation range of the ventilation device, the absorption range of harmful gases is also expanded. By using the extraction box to change the extraction point, multiple types of ventilation and exhaust can be achieved. The inlet pipe does not need to be equipped with branch-shaped secondary pipes for auxiliary ventilation. This effectively improves the cost and convenience of burying the inlet pipe in the shaft. In addition, the partition divides the inlet pipe into two independent spaces, with air entering at the left end and exhaust at the right end. This allows the exhaust device to achieve the discharge of harmful exhaust gases using only a single inlet pipe.

[0029] The embodiments of the present invention are given for illustrative and descriptive purposes only, and are not intended to be exhaustive or to limit the invention to the forms disclosed. Many modifications and variations will be apparent to those skilled in the art. The embodiments were chosen and described in order to better illustrate the principles and practical application of the invention, and to enable those skilled in the art to understand the invention and to design various embodiments with various modifications suitable for a particular purpose.

Claims

1. A method for improving ventilation in extra-long tunnels, characterized in that, Includes the following steps: S1. Pre-reserved tunnel construction: A vertical shaft is constructed outside the mountain, leading directly to the top of the tunnel, and a placement trench is constructed inside the top of the tunnel; S2. Component fixing and assembly: Insert the inlet pipe into the vertical shaft, so that the top of the inlet pipe protrudes outside the mountain and the end of the inlet pipe extends into the installation groove. Fix the motor on the inner wall of the installation groove. Then align the docking seats at both ends of the external air extraction box with the end of the inlet pipe and the connecting pipe. After completing the above operations, fix the support plate to the bottom inner wall of the installation groove to complete the docking of the air extraction box and the inlet pipe. Fix the air collection box to the bottom of the support plate and dock the air collection box with the connecting pipe. Insert the ventilation pipe into both ends of the external air collection box and fix the ventilation pipe to the top of the tunnel. S3. Intermittent ventilation: The air intake fan operates, blowing air from outside the tunnel into the inlet pipe. At the same time, the air extraction box operates, evacuating the air inside the air collection box through the connecting pipe, creating a vacuum in the air collection box. After the air inside the air collection box is evacuated, the air extraction box stops operating and connects the inlet pipe to the connecting pipe. At this time, the valve outside the connecting pipe opens, and the air in the inlet pipe will rush into the air collection box due to the air pressure difference. Subsequently, the valve outside the ventilation pipe opens, and fresh air from the air collection box will enter the ventilation pipe and enter the tunnel through the air outlet. S4. High-power ventilation: The motor drives the air extraction box to rotate, so that the positions of the two suction ports of the air extraction box are reversed. The air intake fan works and blows the air outside the tunnel into the inside of the inlet pipe. At this time, the air extraction box works and can send the air in the inlet pipe into the air collection box through the connecting pipe. Then the ventilation pipe sends fresh air into the tunnel through the air outlet. S5. Exhaust Gas Discharge: The motor drives the extraction box to rotate, so that the extraction port of the extraction box faces the connecting pipe. At the same time, the extraction box connects the connecting pipe and the exhaust pipe. When the extraction box is working, the exhaust gas in the tunnel can be drawn into the ventilation pipe through the air outlet, and then enter the connecting pipe through the air collection box. Subsequently, the exhaust gas can be discharged into the inlet pipe through the exhaust pipe and discharged from the exhaust port.

2. The method for improving ventilation in extra-long tunnels according to claim 1, characterized in that, In step S1, the vertical shaft and the placement trench are interconnected.

3. The method for improving ventilation in extra-long tunnels according to claim 1, characterized in that, In step S2, during the process of connecting the docking seat with the inlet pipe and the connecting pipe, the electric actuator drives the extension pipe to move within the fixed pipe, so that the docking seat extends and connects with the inlet pipe and the connecting pipe.

4. The method for improving ventilation in extra-long tunnels according to claim 1, characterized in that, In step S2, the motor and the vacuum box are integrated into one unit, and the motor is fixed to the inner wall of the mounting slot by locking bolts.

5. A method for improving ventilation in extra-long tunnels according to claim 1, characterized in that, In step S3, when the extraction box extracts air from the collection box, the valve outside the ventilation pipe is closed.

6. A method for improving ventilation in extra-long tunnels according to claim 1, characterized in that, In step S3, during the process of the air collection box ventilating the ventilation pipe, the valves outside the ventilation pipe at each point on the outer end of the air collection box will open and close intermittently in sequence.

7. A method for improving ventilation in extra-long tunnels according to claim 1, characterized in that, In step S4, before the motor drives the vacuum box to rotate, the electric push rod operates to move the extension tube within the fixed tube, causing the docking seat to separate from the inlet tube and the connecting tube.

8. A method for improving ventilation in extra-long tunnels according to claim 1, characterized in that, In step S4, when the air collection box supplies air to the ventilation pipes at each location, all valves outside the ventilation pipes are in the open state.

9. A method for improving ventilation in extra-long tunnels according to claim 1, characterized in that, In step S4, when the extraction box rotates, the bearing swivel can offset the torque of the extraction box rotation by rotating, so that the exhaust pipe is always at a fixed position.

10. A method for improving ventilation in extra-long tunnels according to claim 1, characterized in that, In step S5, the partition divides the inlet pipe into two independent spaces, left and right, with air flowing through the left end and exhausting from the right end.

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