A system and method for double-deck shield tunnel top and side coordinated air supply smoke exhaust

Abstract

The present application relates to a system and method for the coordinated air supply and smoke exhaust of the top and side of a double-deck shield tunnel, which uses the space above the tunnel to set up an independent smoke exhaust duct, which is responsible for the exhaust of the upper layer of smoke and the collection of the lower layer of smoke after purification. Meanwhile, an air supply duct is set up on the top or side, which uniformly supplies fresh air to the upper and lower layers through adjustable valves. The core of the method is dynamic coordinated control: under normal conditions, the system uniformly supplies air to both layers; when a fire occurs, the system intelligently switches modes according to the location of the fire source; if a fire occurs in the lower layer, the smoke is treated by a three-stage filtering and purification assembly in the Y-shaped connecting pipe and then drawn into the top duct for exhaust, while the upper layer continues to supply air; if a fire occurs in the upper layer, the smoke is directly exhausted through the top exhaust port, while the lower layer continues to supply air. The present application solves the problem of ventilation and smoke exhaust of underwater double-deck tunnels and significantly improves the space utilization and disaster prevention efficiency.

Description

Technical Field

[0001] This invention belongs to the field of tunnel ventilation and disaster prevention technology, and relates to a system and method for coordinated air supply and smoke exhaust at the top and sides of a double-layer shield tunnel. Background Technology

[0002] To effectively alleviate traffic congestion and significantly improve urban traffic efficiency, long, double-layered shield tunnels have emerged. However, their operational safety, especially fire safety, has become a focus of widespread public concern. How to fully utilize limited structural space to design ventilation and smoke extraction systems that simultaneously meet the needs of daily operation and fire-related smoke extraction is key to supporting the development of tunnels towards wider cross-sections and longer lengths.

[0003] Conventional shield tunnels utilize the space at the tunnel roof to install independent smoke exhaust ducts, with smoke exhaust outlets connecting to these ducts. Jet fans are installed below the smoke exhaust ducts, creating a system that prioritizes smoke exhaust during fires and utilizes longitudinal ventilation during normal operation. Building upon this, double-layer shield tunnels consider using side space to install smoke exhaust branch pipes connecting to the upper independent smoke exhaust duct, and also utilize side space to install air supply / smoke exhaust ducts, optimizing the ventilation and smoke exhaust system design. However, as tunnel length increases, additional ventilation shafts are needed to create segmented longitudinal ventilation to supplement air supply capacity during normal operation. Given the difficulties in constructing ventilation shafts in underwater tunnels, lateral air supply and smoke exhaust methods (top supply and side exhaust, side supply and side exhaust, etc.) offer a solution. Therefore, in order to take into account the smoke exhaust capacity of the upper and lower tunnels in case of fire, improve the daily ventilation effect and enhance the utilization rate of structural space, it is urgent to develop a system and method for coordinated air supply and smoke exhaust at the top and sides of a double-layer shield tunnel, which can be switched and adjusted in actual scenarios according to the uniform air supply under daily working conditions and the on-demand smoke exhaust under fire conditions. Summary of the Invention

[0004] In view of this, in order to solve the problem that existing technologies are unable to efficiently coordinate the daily ventilation and fire smoke exhaust needs of long double-layer shield tunnels within a limited structural space, especially under the condition that ventilation shafts cannot be added underwater, and the contradiction between ventilation and smoke exhaust efficiency and the development of tunnel length and double-layer is becoming increasingly prominent, the present invention provides a system and method for coordinated air supply and smoke exhaust at the top and sides of a double-layer shield tunnel.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A system for coordinated ventilation and smoke extraction at the top and sides of a double-layer shield tunnel is disclosed. The shield tunnel is vertically divided into a lower driving lane and an upper driving lane. A smoke extraction duct is installed between the upper driving lane and the inner wall of the shield tunnel. Multiple extension pipes I, whose top ends are connected to the smoke extraction duct, are fixedly installed inside the shield tunnel. Multiple connecting pipes I, connected to the bottom ends of the extension pipes I, are installed on one side of the lower driving lane. Smoke extraction outlets with electromagnetic regulating valves are installed at the connection points between the extension pipes I and the lower driving lane. Multiple smoke extraction outlets with electromagnetic regulating valves are opened at the top of the upper driving lane, which are connected to the smoke extraction duct and are equipped with smoke extraction ducts, allowing the smoke from the upper driving lane to enter the smoke extraction duct through these outlets.

[0007] An air supply duct is installed inside the shield tunnel on the side opposite to the smoke exhaust duct. Multiple connecting pipes III are installed on the outer wall of the upper driving lane, which are connected to the upper driving lane and the air supply duct. An air supply inlet and a regulating valve are installed at the connection between connecting pipe III and the upper driving lane. A connecting pipe II is installed on the inner wall of the lower driving lane, which is connected to the lower driving lane and the air supply duct. An air supply inlet and a regulating valve are installed at the connection between connecting pipe II and the lower driving lane. Multiple fireproof and smoke-proof mechanisms are installed on the top walls of the lower and upper driving lanes respectively. The fireproof and smoke-proof mechanisms are located on the same side of each set of connecting pipe I, connecting pipe II, smoke exhaust outlet and connecting pipe III, and are used to descend to isolate smoke in the event of a fire.

[0008] The smoke extraction method based on the above-mentioned coordinated ventilation and smoke extraction system for the top and sides of a double-layer shield tunnel includes the following steps:

[0009] S1. Determine the volumetric flow rate control mode for the air supply inlet and the smoke exhaust outlet;

[0010] The volumetric flow rate control of both the air supply inlet and the smoke exhaust outlet can be solved based on the air volume and the opening angle of the regulating valve.

[0011]

[0012] In the formula: V se,i V represents the volumetric flow rate of each air inlet / exhaust outlet; f Supply air volume / exhaust air volume; θ i Let be the opening angle of the regulating valve inside the i-th air supply inlet / smoke exhaust outlet, and n be the number of outlets that are open. The air supply inlet is the free end of connecting pipe II and connecting pipe III, and the smoke exhaust outlet is the free end of connecting pipe I and smoke exhaust outlet. Regulating valves are installed on both the air supply inlet and the smoke exhaust outlet. The regulating valves are multiple rows of valve plates that are perpendicular to the horizontal direction of the tunnel and whose opening degree is adjustable.

[0013] S2. Determine the opening degree of the regulating valves at each air supply inlet and smoke exhaust outlet:

[0014] The volumetric flow rate V of the i-th air supply inlet / smoke exhaust outlet se,i expression:

[0015]

[0016] In the formula: v i Let θ be the inflow velocity, α be the valve opening angle, and α be the angle between the inflow velocity and the horizontal direction. θi θ is the flow area when the regulating valve is open; a is the length of the regulating valve; h is the height of the regulating valve, which is the same as the height of the smoke exhaust outlet.

[0017] During air supply, based on the energy changes in the flow process of "air supply duct - connecting pipe - tunnel", an energy equation is established, and the relationship between the flow velocity in the regulating valve at the i-th air supply inlet and the local resistance coefficient under the uniform volumetric flow rate mode is obtained as follows:

[0018]

[0019] During smoke exhaust, based on the energy changes in the flow process of "tunnel-connecting pipe-smoke exhaust duct", an energy equation is established, and the relationship between the smoke flow velocity in the regulating valve at the i-th smoke exhaust outlet and the local resistance coefficient is obtained as follows:

[0020]

[0021] In the formula: P se,i P is the static pressure inside the i-th air supply inlet / smoke exhaust outlet; sd,i P is the static pressure at the i-th air supply inlet / smoke exhaust outlet within the air supply duct / smoke exhaust duct; f Static pressure at the beginning of the supply air duct / the end of the smoke exhaust duct; λ sd The friction factor (λ) within the air supply / exhaust duct is calculated based on the surface roughness of the wall material. sp ζ is the friction coefficient of the air supply / exhaust duct connecting pipe; sd,i ζ is the local resistance coefficient within the supply air duct / exhaust air duct at the i-th supply air inlet / exhaust air outlet; sp,i The local resistance coefficient of the airflow within the i-th air supply inlet / exhaust outlet - connecting pipe - exhaust duct; L is the distance from the n-th air supply inlet / exhaust outlet to the beginning of the air supply duct / the end of the exhaust duct; x i D is the distance from the i-th air supply inlet / exhaust outlet to the beginning of the air supply duct / the end of the exhaust duct; sd D is the equivalent diameter of the air supply duct / smoke exhaust duct. sp ρ is the equivalent diameter of the air supply / exhaust duct connection pipe; a air density; ρ s This represents the density of the flue gas.

[0022] The beneficial effects of this invention are as follows:

[0023] 1. The system for coordinated air supply and smoke exhaust at the top and sides of a double-layer shield tunnel disclosed in this invention, through the layout design of the smoke exhaust duct, air supply duct, connecting pipes, and solenoid valves at each air outlet and inlet, can evenly deliver fresh air to the lower and upper driving lanes through connecting pipes II and III under normal operating conditions, ensuring air circulation within the tunnel; under fire conditions, it can quickly switch to smoke exhaust mode, with smoke from the lower driving lane flowing into the smoke exhaust duct through connecting pipe I, the filter and purification components, and extension pipe I, while smoke from the upper driving lane directly enters the smoke exhaust duct through the smoke exhaust outlet, achieving integrated "air supply and smoke exhaust". This solves the problems of traditional tunnel ventilation and smoke exhaust systems having single functions, slow switching between operating conditions, and the need to efficiently coordinate the daily ventilation and fire smoke exhaust requirements of long double-layer shield tunnels within limited structural space, especially under conditions where ventilation shafts cannot be added underwater, where the contradiction between ventilation and smoke exhaust efficiency and the increasing length and double-layer development of tunnels is becoming increasingly prominent.

[0024] 2. The system disclosed in this invention for coordinated ventilation and smoke extraction at the top and sides of a double-layer shield tunnel, when a fire occurs, causes the electromagnetic suction ring of the fireproof and smoke-proof mechanism to be de-energized, and the torsion spring to quickly release its stored energy, driving the winding roller shaft to rotate. The fireproof roller shutter falls vertically under the action of the counterweight strip, forming a closed isolation zone on both sides of the fire point within seconds, effectively blocking the back-and-forth movement of smoke and preventing the spread of fire and toxic smoke to non-fire areas. The fireproof roller shutter is made of silicon-titanium alloy fireproof cloth with a high fire resistance limit. Combined with the sealing strip of the door frame and the sealing design of the fire door, the smoke-proof sealing performance is further improved, buying valuable time for personnel evacuation and fire fighting.

[0025] 3. The system for coordinated air supply and smoke exhaust at the top and sides of a double-layer shield tunnel disclosed in this invention uses a three-stage purification structure of "metal filter + activated carbon adsorption layer + ceramic catalytic layer" in the filter and purification components installed in connecting pipe I, connecting pipe II, and connecting pipe III. The metal filter can intercept large particles; the activated carbon adsorption layer can efficiently adsorb toxic and harmful gases such as CO and VOCs, reducing toxicity; the ceramic catalytic layer can catalytically decompose some harmful substances under high temperature conditions, significantly reducing pollution to the surrounding environment. The purification components are fixed with detachable slots, making later replacement and maintenance convenient and ensuring long-term stable purification effect.

[0026] 4. The system for coordinated ventilation and smoke extraction at the top and sides of a double-layer shield tunnel disclosed in this invention features a reset adjustment mechanism. Through the cooperation of drive motor I, transmission gears, and rack and pinion guide rails, the sliding block can be precisely moved along the guide rail to the target fireproof and smoke-proof mechanism position. The electric push rod mechanism, through a connecting rod assembly, pushes the sliding base plate to move, achieving rapid docking of the spline sleeve and spline shaft I. Then, drive motor II drives the winding roller shaft to rotate, completing the automatic winding and reset of the fireproof roller shutter. The entire reset process requires no manual climbing or close-range operation, exhibiting a high degree of automation, significantly reducing the labor intensity of maintenance personnel, improving system reset efficiency, and avoiding the safety risks that may arise from manual operation.

[0027] Other advantages, objectives, and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination, or may be learned from practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0028] To make the objectives, technical solutions, and advantages of the present invention clearer, the preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, wherein:

[0029] Figure 1 This is a three-dimensional structural diagram of a double-layer shield tunnel according to Embodiment 1 of the present invention;

[0030] Figure 2 This is a three-dimensional structural diagram of the double-layer shield tunnel from another perspective, according to Embodiment 1 of the present invention.

[0031] Figure 3 This is a schematic diagram of the connecting pipe I structure in this invention;

[0032] Figure 4 This is a cross-sectional view of connecting pipe I in this invention;

[0033] Figure 5 This is a schematic diagram of the fireproof and smoke-proof mechanism in this invention;

[0034] Figure 6 This is a schematic diagram of the installation structure of the electromagnetic suction ring and torsion spring in this invention;

[0035] Figure 7 This is a schematic diagram of the reset adjustment mechanism in this invention;

[0036] Figure 8 This is a schematic diagram of the reset adjustment mechanism from another perspective in this invention;

[0037] Figure 9 This is a front view of the double-layer shield tunnel according to Embodiment 2 of the present invention.

[0038] Reference numerals: 1. Shield tunnel; 2. Lower level roadway; 3. Lower level evacuation corridor; 4. Upper level roadway; 5. Upper level evacuation corridor; 6. Smoke exhaust duct; 7. Extension pipe I; 8. Connecting pipe I; 9. Air supply duct; 91. Extension pipe II; 10. Connecting pipe II; 11. Connecting pipe III; 12. Regulating valve I; 13. Regulating valve II; 14. Smoke exhaust fan; 15. Filter purification assembly; 16. Fireproof and smoke-proof mechanism; 161. Mounting base; 162. Guide roller; 163. Rewinding roller; 164. Connecting... 165. Connecting cylinder body; 166. Splined shaft I; 167. Fireproof roller shutter; 168. Electromagnetic suction ring; 179. Torsion spring; 18. Reset adjustment mechanism; 190. Guide slide rail; 191. Sliding block; 192. Rack and pinion guide rail; 193. Drive motor I; 194. Transmission gear; 195. Drive motor II; 196. Fixed frame; 197. Splined shaft II; 198. Splined sleeve; 199. Sliding base plate; 1910. Electric push rod mechanism; 1911. Linkage assembly; 1912. Smoke exhaust outlet. Detailed Implementation

[0039] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0040] Example 1

[0041] like Figure 1 , 2 The system shown is for coordinated ventilation and smoke extraction at the top and sides of a double-layer shield tunnel. Shield tunnel 1 has a circular cross-section structure with multiple steel plates embedded in its inner wall. These steel plates are evenly distributed longitudinally, have rust-proofed surfaces, and are welded to the secondary lining of shield tunnel 1 with reinforcing bars. They are used to subsequently fix components such as the smoke extraction duct 6 and extension pipe I 7. The interior of shield tunnel 1 is vertically divided into a lower driving lane 2 and an upper driving lane 4. The dividing structure is a reinforced concrete partition. Gaps are left between the partition and the inner wall of shield tunnel 1 on both sides for arranging pipelines and ventilation channels. The surface of the partition is treated with anti-slip and wear-resistant material to meet traffic requirements. Lower evacuation corridor 3 and upper evacuation corridor 5 are set parallel to each other on both sides of the lower driving lane 2 and upper driving lane 4, respectively. The inner walls of the evacuation corridors are decorated with fireproof boards, which are fixed to the keel with self-tapping screws. The keel is welded to the steel plate embedded in the inner wall of the shield tunnel 1. Handrails are fixedly installed at 1.2 meters along the height direction in the evacuation corridor. The handrails are made of stainless steel pipes and are fixed to the inner wall by brackets to facilitate the gripping of personnel during evacuation.

[0042] Multiple doorways are evenly spaced along the side of the lower evacuation corridor 3 near the lower roadway 2. Each doorway is hinged to a fire door, and the door frame is fixed to the inner wall of the doorway with expansion bolts. A sealing strip is installed between the fire door and the door frame when the fire door is closed to ensure smoke isolation. The upper evacuation corridor 5 has a symmetrical structure to the lower evacuation corridor 3, and its doorways and fire doors are installed in the same way, facilitating rapid evacuation in emergencies. A space is reserved between the top of the upper roadway 4 and the inner wall of the shield tunnel 1. This space is for a smoke exhaust duct 6, which is welded from stainless steel plates, and the inner wall is polished to reduce airflow resistance. The top of the partition plate of the smoke exhaust duct 6 is fixed to the inner wall of the shield tunnel 1 by multiple support hangers. The support hangers are made of angle steel, with one end welded to the pre-embedded steel plate of the shield tunnel 1 and the other end connected to the top flange of the partition plate of the smoke exhaust duct 6 by bolts. The support hangers are set every 3 meters along the longitudinal direction of the smoke exhaust duct 6 to ensure that the partition plate of the smoke exhaust duct 6 is installed stably and without shaking.

[0043] An extension pipe I7 is fixedly installed at regular intervals along the longitudinal direction inside shield tunnel 1. The extension pipe I7 is arranged vertically and its outer wall is fitted with a heat insulation layer to prevent excessively high flue gas temperature from transferring heat to the surrounding structure. The top of the extension pipe I7 is sealed to the bottom opening of the flue gas duct 6 through a flange. The flange mating surface is equipped with a high-temperature resistant sealing gasket to prevent flue gas leakage. A reinforcing rib is also provided at the connection flange between the extension pipe I7 and the flue gas duct 6. The reinforcing rib is welded between the outer wall of the extension pipe I7 and the flange to improve the connection strength. The bottom end of the extension pipe I7 extends to the left side of the lower carriageway 2 and is connected to the connecting pipe I8 fixed through the left side of the lower carriageway 2.

[0044] like Figure 3 The connecting pipe I8 shown is Y-shaped, formed by bending seamless steel pipe with a rounded transition at the bend. The inner wall is polished smooth to reduce airflow resistance. Multiple fixed supports are welded to the outer wall of connecting pipe I8, and these supports are fixed to the side wall of the lower driving lane 2 using expansion bolts. Supports are installed every 1.5 meters along the length of connecting pipe I8 to prevent deformation due to its own weight or airflow impact. One end of connecting pipe I8 is welded to the bottom end of extension pipe I7, while the other two ends penetrate the side wall of the lower driving lane 2 and extend into the interior. Two regulating valves, I12 and II13, are installed at the two ports located within the lower driving lane 2. Both regulating valves I12 and II13 are electrically adjustable, and their valve bodies are bolted to the flange of connecting pipe I8, allowing for opening adjustment. The valve shaft of the regulating valve is connected to the valve body at both ends by bearings. Multiple blades are fixed on the valve shaft. The blades are made of aluminum alloy and have an anti-corrosion treatment. Sealing gaskets are installed between the blades to ensure sealing when closed. The electric actuator of the regulating valve is fixed on the outside of the valve body and is connected to the tunnel's control system through wires, enabling remote control and automatic adjustment.

[0045] like Figure 4 As shown, a filter purification assembly 15 is fixedly installed inside the connecting pipe 18 between the two regulating valves Ⅱ13. The filter purification assembly 15 consists of a metal filter screen, an activated carbon adsorption layer, and a ceramic catalytic layer. The metal filter screen, located near the regulating valves Ⅱ13, is made of woven stainless steel wire with a suitable mesh size and is detachably fixed via slots for easy cleaning of debris. The activated carbon adsorption layer uses honeycomb activated carbon and is fixed by a frame. The frame is adapted to the slots on the inner wall of the connecting pipe 18 and is used to adsorb toxic gases such as CO and VOCs. The ceramic catalytic layer uses a honeycomb ceramic carrier with a catalytic coating on the surface and is fixed inside the connecting pipe 18 by bolts. It can catalytically decompose some harmful substances under high-temperature conditions. Sealing strips are provided at the edges of all three layers to ensure that all gases are purified, and all layers are detachably fixed to the inner wall of the connecting pipe 18 via slots for easy replacement and maintenance.

[0046] A smoke exhaust fan 14 is fixedly installed at one end of the connecting pipe I8 near the extension pipe I7. The outer casing of the smoke exhaust fan 14 is welded from steel plate, and the surface of the casing is treated with an anti-corrosion coating. The air inlet of the fan is equipped with a protective net to prevent foreign objects from entering the fan. A shock-absorbing pad made of rubber is installed between the fan and the support to reduce the transmission of vibration generated during the operation of the fan. The motor of the fan is a high-temperature resistant type and can work normally in high-temperature environments. The outer casing of the smoke exhaust fan 14 is fixed to the outer wall of the connecting pipe I8 through the support, and its air outlet is connected to the inside of the connecting pipe I8 to provide power for the flow of flue gas.

[0047] like Figure 1 As shown, the top of the upper driving lane 4 has a smoke exhaust port 18 at regular intervals along the longitudinal direction. The smoke exhaust port 18 is a rectangular opening, and its edges are fixed with a grid made of stainless steel by bolts. The spacing between the grid bars is appropriate to prevent foreign objects from entering the smoke exhaust duct 6. Below the grid is an adjustable electromagnetic valve that regulates the amount of smoke entering the smoke exhaust port 18 and guides the smoke smoothly into the smoke exhaust duct 6. Each smoke exhaust port 18 is connected to the smoke exhaust duct 6, ensuring that the smoke in the upper driving lane 4 can quickly flow into the smoke exhaust duct 6.

[0048] A ventilation duct 9 is installed parallel to the length of the inner side of the shield tunnel 1. The ventilation duct 9 is made of reinforced concrete and coated with anti-corrosion paint on the inner wall. An inspection port is provided on one side of the ventilation duct 9. The inspection port is sealed by a cover plate and the cover plate is fixed by bolts for easy maintenance. Flange interfaces are provided at both ends of the ventilation duct 9 for connection with external fresh air ducts.

[0049] A connecting pipe III11 is fixedly installed longitudinally at regular intervals along the inner right side wall of the upper driving lane 4. Connecting pipe III11 is a horizontally arranged circular pipe, one end of which penetrates the side wall of the upper driving lane 4 and extends into the interior, with a grille installed at the port. The other end is sealed to the side wall opening of the air supply duct 9 via a flange. A connecting pipe II10 is fixedly installed along the inner right side wall of the lower driving lane 2. The structure of connecting pipe II10 is the same as connecting pipe III11, with one end extending into the interior of the lower driving lane 2 and the other end connected to the air supply duct 9, ensuring that fresh air in the air supply duct 9 can be delivered to the upper and lower driving lanes respectively. An air supply inlet and a regulating valve are provided at the connection point between connecting pipe III11 and the upper driving lane 4, and an air supply inlet and a regulating valve are also provided at the connection point between connecting pipe II10 and the lower driving lane 2. Filter and purification components 15 are also installed inside connecting pipe II10 and connecting pipe III11 to purify the air supplied to the lower driving lane 2 and the upper driving lane 4.

[0050] Multiple fireproof and smoke-proof mechanisms 16 are fixedly installed on the top walls of both the lower-level driveway 2 and the upper-level driveway 4. These mechanisms 16 are located on the same side of each set of connecting pipes I 8, II 10, smoke exhaust outlet 18, and III 11. The spacing between adjacent fireproof and smoke-proof mechanisms 16 is appropriate, allowing for the rapid formation of an isolation zone in the event of a fire, preventing smoke from spreading back and forth. Figure 5 As shown, each fireproof and smoke-proof mechanism 16 includes two mounting bases 161. The mounting base 161 is welded from steel plates, with a pre-embedded steel plate at the bottom. The pre-embedded steel plate is fixed to the side wall of the driveway by expansion bolts. A bearing seat is provided on one side of the mounting base 161, and a deep groove ball bearing is installed inside the bearing seat. A guide roller 162 and a take-up roller 163 are mounted between them via the bearing's rotation. The outer wall of the guide roller 162 is fitted with a rubber sleeve, and the surface of the rubber sleeve is treated with anti-slip material to reduce friction with the fireproof roller shutter 166 and extend the service life of the fireproof roller shutter 166. Retaining rings are provided at both ends of the guide roller 162 to prevent the fireproof roller shutter 166 from deviating. The take-up roller shaft 163 is made of seamless steel pipe with end plates welded to both ends. The end plates are provided with keyways and are connected and fixed to the spline shaft I 165 by keys. The outer wall of the take-up roller shaft 163 is provided with grooves. One end of the fireproof roller shutter 166 is fixed in the groove by bolts to ensure that the fireproof roller shutter 166 is neatly arranged and does not entangle when it is rolled up.

[0051] like Figure 6As shown, a fireproof roller shutter 166 is fixedly wound around the outer wall of the winding roller shaft 163. The fireproof roller shutter 166 is made of silicon-titanium alloy fireproof cloth, and its fire resistance limit meets the design requirements. Reinforcing edges are provided on both sides, with steel wire ropes embedded within the reinforcing edges to enhance the tensile strength of the fireproof roller shutter 166. The other end of the fireproof roller shutter 166 hangs down naturally after passing over the guide roller 162, and a counterweight is fixed at the bottom. The counterweight is made of steel pipe filled with concrete, and sliders are provided at both ends of the counterweight. The sliders are adapted to the guide rails on both sides of the roadway to ensure vertical and smooth descent without tilting. When encountering an obstacle (such as a vehicle) during descent, the roller shutter can partially wrap around the shape of the obstacle and continue descending, forming an obstruction as much as possible. At the same time, the system alarms to indicate the presence of an obstacle in the isolation section. A vehicle height detection device can also be installed inside the tunnel to scan the corresponding section before the fireproof roller shutter 166 operates.

[0052] The outer wall of the take-up roller shaft 163 is also fitted with a connecting cylinder 164, which is a cylindrical shell. One end of the connecting cylinder 164 is fixed to one side of the mounting base 161 by bolts. The outer wall of the take-up roller shaft 163 is fitted with an electromagnetic suction ring 167. The outer shell of the electromagnetic suction ring 167 is made of cast iron, and a coil is provided inside. The coil is connected to the control system through wires. The adsorption surface of the electromagnetic suction ring 167 is provided with a wear-resistant pad. The pad is made of copper to reduce wear during adsorption. The fixing seat of the electromagnetic suction ring 167 is fixed to the inner wall of the connecting cylinder 164 by bolts to ensure a firm installation. Its adsorption end is set opposite to the end face of the take-up roller shaft 163 for fixing the take-up roller shaft 163 in normal conditions.

[0053] The outer wall of the take-up roller shaft 163 is also fitted with a torsion spring 168 located inside the connecting cylinder 164. The torsion spring 168 is made of high-temperature resistant spring steel with a rust-proof surface treatment. Hooks are provided at both ends of the spring, connecting to the end plate of the take-up roller shaft 163 and the hooks on the inner wall of the connecting cylinder 164, respectively, ensuring reliable spring installation and stable energy storage. Under normal conditions, the torsion spring 168 is in an energy-storing state. When the electromagnetic suction ring 167 is de-energized and releases the take-up roller shaft 163, the torsion spring 168 can drive the take-up roller shaft 163 to rotate, thereby releasing the fireproof roller shutter 166 to achieve smoke isolation.

[0054] like Figure 7 , 8As shown, a set of reset adjustment mechanisms 17 are respectively installed on one inner wall of the lower driving lane 2 and the upper driving lane 4 to reset the fireproof and smoke-proof mechanism 16 after it has been opened. Each reset adjustment mechanism 17 includes a guide rail 171, which is made of channel steel and has a lubrication groove on its inner wall. The lubrication groove is filled with grease to reduce the friction between the sliding block 172 and the guide rail 171. Limiting blocks are provided at both ends of the guide rail 171 to prevent the sliding block 172 from slipping off. The guide rail 171 is fixed to the inner wall of the driving lane by bolts, and its length is adapted to the arrangement length of the fireproof and smoke-proof mechanism 16 in the corresponding driving lane.

[0055] The sliding block 172, which is slidably mounted inside the guide rail 171, is made of aluminum alloy profile and has an internal mounting cavity. Both drive motor I 174 and drive motor II 176 are fixed in the mounting cavity by bolts. The inner wall of the mounting cavity has heat dissipation holes to facilitate motor heat dissipation. The bottom slider of the sliding block 172 is made of wear-resistant nylon material and fits tightly with the inner wall of the guide rail 171 to ensure smooth sliding.

[0056] A drive motor I 174 is fixedly installed inside the sliding block 172. The housing of the drive motor I 174 is equipped with heat sinks to improve heat dissipation. The output shaft of the motor is connected to the transmission gear 175 via a coupling. The coupling is an elastic coupling to reduce vibration transmission. The base of the motor is fixed to the mounting cavity of the sliding block 172 by a shock-absorbing pad to further reduce vibration. The transmission gear 175 is made of alloy steel, and the tooth surface is ground. The meshing clearance with the rack and pinion guide 173 is controlled within a reasonable range to ensure smooth transmission.

[0057] A rack guide rail 173 is fixedly installed on one side of the guide rail 171. The rack guide rail 173 is fixed to one side of the guide rail 171 by bolts. The tooth surface of the rack guide rail 173 is hardened to improve wear resistance. The two ends of the rack guide rail 173 are provided with limit teeth, which cooperate with the transmission gear 175 to prevent the sliding block 172 from exceeding the stroke. The rack guide rail 173 meshes with the transmission gear 175. The drive motor I 174 drives the transmission gear 175 to rotate, which can drive the sliding block 172 to move along the guide rail 171.

[0058] A fixed frame 177 is fixedly installed on one side of the sliding block 172. The fixed frame 177 is welded from angle steel and the surface is treated with anti-corrosion. The inner wall of the frame is provided with a slide rail. The sliding base plate 1710 is provided with sliders on both sides. The sliders are adapted to the slide rail to ensure that the sliding base plate 1710 slides smoothly.

[0059] An electric actuator mechanism 1711 is fixedly mounted on one side of the fixed frame 177. The housing of the electric actuator mechanism 1711 is fixed to one side of the fixed frame 177 via a bracket made of angle steel. A connecting rod assembly 1712 is rotatably connected to the output end of the electric actuator mechanism 1711. The connecting rod assembly 1712 consists of two connecting rods connected by a hinge shaft. The connecting rods are made of stainless steel tubing. A grease nipple is provided on the hinge shaft for easy grease application. Both ends of the connecting rods are equipped with hinge seats, which are respectively hinged to the telescopic rod of the electric actuator mechanism 1711 and the sliding base plate 1710, ensuring flexible transmission without jamming. Through the telescopic movement of the electric actuator mechanism 1711, the sliding base plate 1710 can be pushed to slide along the fixed frame 177.

[0060] A drive motor II 176 is also fixedly installed inside the sliding block 172. The structure of the drive motor II 176 is the same as that of the drive motor I 174. Its housing is equipped with heat sinks. The output shaft of the motor is connected to the spline shaft II 178 through a coupling. The coupling is an elastic coupling. The base of the motor is fixed to the mounting cavity of the sliding block 172 through a shock-absorbing pad.

[0061] A spline sleeve 179 is slidably fitted onto the spline shaft II 178. The inner wall of the spline sleeve 179 is provided with a spline groove, which is adapted to the spline teeth of the spline shaft II 178 and the spline shaft I 165. The two ends of the spline sleeve 179 are provided with guide cone surfaces to facilitate docking with the spline shaft I 165. The outer wall of the spline sleeve 179 is connected to the sliding base plate 1710 through a bearing. The bearing is a deep groove ball bearing to ensure smooth rotation. When the fireproof roller shutter 166 needs to be rolled up, the electric push rod mechanism 1711 pushes the sliding base plate 1710 to move, causing the spline sleeve 179 to dock with the spline shaft I 165. Then the drive motor II 176 starts, and through the transmission of the spline shaft II 178, the spline sleeve 179 and the spline shaft I 165, the winding roller shaft 163 is driven to rotate, and the fireproof roller shutter 166 is rolled up and reset. At the same time, the torsion spring 168 stores energy, and the electromagnetic suction ring 167 is energized to attract and fix the winding roller shaft 163.

[0062] Example 2

[0063] like Figure 9 As shown, the difference between Embodiment 2 and Embodiment 1 is that a space is reserved between the top of the upper driving lane 4 and the inner wall of the shield tunnel 1. This space is divided into two chambers by a concrete slab. The left chamber is the smoke exhaust duct 6 and the right chamber is the air supply duct 9. The partition wall between the smoke exhaust duct 6 and the air supply duct 9 is equipped with a device for purifying fire smoke at intervals along the longitudinal direction, forming purified air flowing laterally from the smoke exhaust duct 6 to the air supply duct 9, which can ensure that the airflow forms a lateral circulation throughout the tunnel.

[0064] The inner wall of the smoke exhaust duct 6 is polished to reduce airflow resistance. The top of the partition plate of the smoke exhaust duct 6 is fixed to the inner wall of the shield tunnel 1 by multiple support hangers. The support hangers are made of angle steel, with one end welded to the pre-embedded steel plate of the shield tunnel 1, and the other end connected to the top flange of the partition plate of the smoke exhaust duct 6 by bolts. The support hangers are set every 3 meters along the longitudinal direction of the smoke exhaust duct 6 to ensure that the partition plate of the smoke exhaust duct 6 is installed stably and without shaking.

[0065] The upper driving lane 4 has a smoke exhaust port 18 at regular intervals along its longitudinal direction on the top partition. Each smoke exhaust port 18 is a rectangular opening with a stainless steel mesh grille bolted to its edge to prevent foreign objects from entering the smoke exhaust duct 6. Below the grille is an adjustable electromagnetic valve that regulates the amount of smoke entering the smoke exhaust port 18 and guides the smoke smoothly into the smoke exhaust duct 6. Each smoke exhaust port 18 is connected to the smoke exhaust duct 6, ensuring that the smoke in the upper driving lane 4 can quickly flow into the smoke exhaust duct 6.

[0066] A connecting pipe Ⅲ11 is fixedly installed at regular intervals along the right inner wall of the upper driving lane 4. The connecting pipe Ⅲ11 is a horizontally arranged circular pipe, one end of which penetrates the side wall of the upper driving lane 4 and extends into the interior. The port is also equipped with a grid mesh. A connecting pipe Ⅱ10 is fixedly installed along the right inner wall of the lower driving lane 2. The ends of the corresponding connecting pipes Ⅱ10 and Ⅲ11 away from the driving lane are connected to the same extension pipe Ⅱ91 located in the shield tunnel 1. The other ends of the multiple extension pipes Ⅱ91 away from the air supply duct 9 are closed to ensure that fresh air in the air supply duct 9 can be delivered to the upper and lower driving lanes along the extension pipes Ⅱ91 respectively.

[0067] Fire detectors are installed at regular intervals along the longitudinal direction of the tunnel's carriageway, fixed to the ceiling. All electrical components are connected to the tunnel's central control system via wires. When a fire occurs, if a fire breaks out in the lower carriageway 2, the corresponding fire detector sends a signal. Upon receiving the signal, the control system de-energizes the electromagnetic suction ring 167. The torsion springs 168 in the fireproof and smoke-proof mechanisms 16 on both sides of the fire point release energy to drive the winding roller shaft 163 to rotate, causing the fireproof roller shutter 166 to fall rapidly, forming an isolation zone to block the spread of smoke. Simultaneously, the control system opens the regulating valve II 13, starts the smoke exhaust fan 14, and allows smoke from the lower carriageway 2 to enter through the connecting pipe I 8. After passing through the regulating valve II 13 and the filter purification component 15 for purification, smoke flows through the extension pipe I 7 into the smoke exhaust duct 6 and is finally discharged from the tunnel. The air supply duct 9 delivers fresh air to the upper carriageway 4 and the lower evacuation corridor 3 through the connecting pipe III 11, ensuring the safe evacuation of personnel.

[0068] The system operates as follows: Under normal ventilation conditions, the electromagnetic suction ring 167 is energized to attract and fix the winding roller shaft 163, and the fireproof roller shutter 166 remains in a wound state, without affecting air circulation in the driveway. Fresh air is introduced into the air supply duct 9 and delivered to the lower driveway 2 and the upper driveway 4 through connecting pipes II 10 and III 11 respectively, achieving daily ventilation. During natural ventilation, simply close the regulating valve II 13 and open the regulating valve I 12 to avoid long-term use of the filter purification component 15.

[0069] If a fire occurs in the upper driving lane 4, the fireproof roller shutters 166 on both sides of the fire point will fall to isolate it, the smoke exhaust port 18 will open, and the smoke in the upper driving lane 4 will be discharged into the smoke exhaust duct 6 through the smoke exhaust port 18. The air supply duct 9 will supply fresh air to the lower driving lane 2 and the upper evacuation corridor 5 through the connecting pipe II 10.

[0070] After the fire is extinguished, when the fireproof roller shutter 166 needs to be reset, the control system starts the drive motor I 174, which drives the sliding block 172 to move along the guide rail 171 to the position of the corresponding fireproof and smoke-proof mechanism 16. Then, the electric push rod mechanism 1711 is started, which pushes the sliding base plate 1710 to move, so that the spline sleeve 179 is connected to the spline shaft I 165. The drive motor II 176 is started, which drives the winding roller shaft 163 to rotate and wind up the fireproof roller shutter 166. After winding is completed, the electromagnetic suction ring 167 is energized to attract and fix the winding roller shaft 163. The electric push rod mechanism 1711 is reset, which drives the spline sleeve 179 to disengage from the spline shaft I 165. The drive motor I 174 drives the sliding block 172 to move to the position of the next fireproof and smoke-proof mechanism 16. The above actions are repeated to complete the reset of all fireproof roller shutters 166.

[0071] Fire detectors are installed at regular intervals along the longitudinal direction of the tunnel lanes and fixed to the ceiling. The system also includes a PLC controller, which is electrically connected to the fire detectors, drive motor I 174, drive motor II 176, electric push rod mechanism 1711, electromagnetic suction ring 167, regulating valve I 12, regulating valve II 13, and smoke exhaust fan 14. The PLC controller is used to receive signals from the fire detectors and control the components to work together in a preset sequence: In case of fire, the electromagnetic suction ring 167 is first de-energized to release the fireproof roller shutter 166, and after a 1-second delay, the corresponding smoke exhaust fan 14 and regulating valve II 13 are opened, while the air supply components in non-fire areas are kept in operation; during reset, the spline sleeve 179 is first connected to the spline shaft I 165, and then the drive motor II 176 is started to roll up the fireproof roller shutter 166. After the rolling is completed, the electromagnetic suction ring 167 is energized to attract and fix it.

[0072] The above solution achieves the theoretical goal of uniform air supply under normal operating conditions and on-demand smoke extraction under fire conditions:

[0073] Determine the volumetric flow rate control mode for the air supply inlet and the smoke exhaust outlet;

[0074] The volumetric flow rate control of both the air supply inlet and the smoke exhaust outlet can be solved based on the air volume and the opening angle of the regulating valve.

[0075]

[0076] In the formula: V se,i V represents the volumetric flow rate of each air inlet / exhaust outlet; f Air volume (supply air volume / exhaust air volume); θ i Let be the opening angle of the regulating valve inside the i-th air supply inlet / smoke exhaust outlet, and n be the number of outlets that are open. The air supply inlet is the free end of connecting pipe II 10 and connecting pipe III 11, and the smoke exhaust outlet is the free end of connecting pipe I 8 and smoke exhaust outlet 18. Regulating valves are installed on both the air supply inlet and the smoke exhaust outlet. The regulating valves are multiple rows of valve plates that are perpendicular to the horizontal direction of the tunnel and whose opening degree is adjustable.

[0077] Among them, the air supply is suitable for the uniform volumetric flow rate control mode, that is, the air supply volume is evenly distributed to each air supply inlet according to the number of air supply inlets opened; the smoke exhaust is suitable for the on-demand adjustment mode of flue gas volumetric flow rate, that is, based on the amount of flue gas in each smoke exhaust outlet-smoke exhaust outlet section, the smoke exhaust air volume and valve opening angle are adjusted to maximize the flue gas volumetric flow rate of the smoke exhaust outlet.

[0078] ② Determine the opening degree of the regulating valves at each air supply inlet and smoke exhaust outlet:

[0079] The volumetric flow rate V of the i-th air supply inlet / smoke exhaust outlet se,i expression:

[0080]

[0081] In the formula: v i Let θ be the inflow velocity, α be the valve opening angle (the angle between the valve plate and the horizontal direction), and S be the inflow velocity. θi θ represents the flow area when the regulating valve is open; a represents the length of the regulating valve; and h represents the height of the regulating valve, which is the same as the height of the smoke exhaust outlet.

[0082] During air supply, based on the energy changes in the flow process of "air supply duct - connecting pipe - tunnel", an energy equation is established, and the relationship between the flow velocity in the regulating valve at the i-th air supply inlet and the local resistance coefficient under the uniform volumetric flow rate mode is obtained as follows:

[0083]

[0084] During smoke exhaust, based on the energy changes in the flow process of "tunnel-connecting pipe-smoke exhaust duct", an energy equation is established, and the relationship between the smoke flow velocity in the regulating valve at the i-th smoke exhaust outlet and the local resistance coefficient is obtained as follows:

[0085]

[0086] In the formula: P se,i P is the static pressure inside the i-th air supply inlet / smoke exhaust outlet; sd,i P is the static pressure at the i-th air supply inlet / smoke exhaust outlet within the air supply duct / smoke exhaust duct; f Static pressure at the beginning of the supply air duct / the end of the smoke exhaust duct; λ sd The friction factor (λ) within the air supply / exhaust duct is calculated based on the surface roughness of the wall material. sp ζ is the friction coefficient of the air supply / exhaust duct connecting pipe; sd,i ζ is the local resistance coefficient within the supply air duct / exhaust air duct at the i-th supply air inlet / exhaust air outlet; sp,i The local resistance coefficient of the airflow within the i-th air supply inlet / exhaust outlet (regulating valve) - connecting pipe - exhaust duct; L is the distance from the n-th air supply inlet / exhaust outlet (regulating valve) to the beginning of the air supply duct / the end of the exhaust duct; x i D is the distance from the i-th air supply inlet / exhaust outlet to the beginning of the air supply duct / the end of the exhaust duct; sd D is the equivalent diameter of the air supply duct / smoke exhaust duct. sp ρ is the equivalent diameter of the air supply / exhaust duct connection pipe; a air density; ρ s This represents the density of the flue gas.

[0087] Specifically, during smoke exhaust, the volumetric flow rate of each smoke exhaust outlet is maximized, and the opening degree of each regulating valve is determined according to the derivative method.

[0088]

[0089] Therefore, given the parameters of the supply air duct / exhaust air duct (height, width), the parameters of the supply air inlet / exhaust air outlet (length, height, spacing, etc.), the number of regulating valves open, and the supply air volume / exhaust air volume, it is only necessary to determine the local resistance coefficient ζ. se,i and ζ sd,i The flow velocity v inside the regulating valve can then be obtained. se,i , regulating valve opening θ i The relationship is such that the volumetric flow rate can be controlled by adjusting the valve opening.

[0090] Therefore, based on CFD numerical simulation and field measurements, the pressure and velocity at each air inlet and exhaust outlet under different control valve openings were obtained, and the local resistance coefficient was calculated. Through power function fitting, the mathematical relationship between the local resistance coefficient and the control valve opening was obtained. Combined with the determined volumetric flow rate control mode, the opening of each control valve can be solved.

[0091]

[0092]

[0093] Therefore, a database of regulating valve opening degree, local resistance coefficient, and flow velocity is established in advance. In practice, the supply air volume / exhaust smoke volume and the opening sequence of the regulating valve are determined according to the requirements, thereby determining the volumetric flow rate of the supply air inlet / exhaust smoke outlet and the opening degree of each regulating valve.

[0094] Implementation steps for switching and adjusting between normal operating conditions and fire operating conditions:

[0095] During normal operation, the smoke exhaust is turned off, and air is supplied evenly between the upper and lower floors;

[0096] In the event of a fire in the upper lane, the upper air supply is shut off and the smoke exhaust is turned on, while the lower air supply continues.

[0097] In the event of a fire in the lower lane, the lower-level air supply is shut off while the smoke exhaust is turned on, and the upper-level air supply continues.

[0098] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A system for coordinated ventilation and smoke extraction at the top and sides of a double-layer shield tunnel, characterized in that, The shield tunnel (1) is vertically divided into a lower lane (2) and an upper lane (4); a smoke exhaust duct (6) is provided between the upper lane (4) and the inner wall of the shield tunnel (1); multiple extension pipes I (7) with their top ends connected to the smoke exhaust duct (6) are fixedly installed inside the shield tunnel (1); multiple connecting pipes I (8) with their bottom ends connected to the extension pipes I (7) are provided on one side of the lower lane (2); a smoke exhaust outlet with an electromagnetic regulating valve is provided at the connection between the extension pipes I (7) and the lower lane (2); multiple smoke exhaust outlets (18) connected to the smoke exhaust duct (6) are opened at the top of the upper lane (4); an electromagnetic regulating valve is installed at the smoke exhaust outlet (18) so that the smoke from the upper lane (4) can enter the smoke exhaust duct (6) through it. An air supply duct (9) is provided in the shield tunnel (1) on the opposite side of the smoke exhaust duct (6). Multiple connecting pipes III (11) connected to the upper driving lane (4) and the air supply duct (9) are provided on the outer wall of the upper driving lane (4). An air supply inlet and a regulating valve are provided at the connection between the connecting pipe III (11) and the upper driving lane (4). A connecting pipe II (10) connected to the lower driving lane (2) and the air supply duct (9) is provided on the inner wall of the lower driving lane (2). An air supply inlet and a regulating valve are provided at the connection between the connecting pipe II (10) and the lower driving lane (2). Multiple fireproof and smoke-proof mechanisms (16) are provided on the top walls of the lower driving lane (2) and the upper driving lane (4). The fireproof and smoke-proof mechanisms (16) are located on the same side of each set of connecting pipe I (8), connecting pipe II (10), smoke exhaust port (18) and connecting pipe III (11), and are used to descend to isolate smoke in case of fire.

2. The system for coordinated ventilation and smoke extraction at the top and sides of a double-layer shield tunnel as described in claim 1, characterized in that, The connecting pipe I (8) is Y-shaped, and its two ports located in the lower driving lane (2) are respectively equipped with regulating valve I (12) and regulating valve II (13). A filter purification component (15) is provided between the regulating valves II (13). A smoke exhaust fan (14) is provided at one end of the connecting pipe I (8) near the extension pipe I (7), so that the fire smoke in the lower driving lane (2) can be filtered and purified before being drawn into the smoke exhaust duct (6). Filter purification components (15) are also provided in the connecting pipe II (10) and the connecting pipe III (11) to purify the air sent into the lower driving lane (2) and the upper driving lane (4).

3. The system for coordinated ventilation and smoke extraction at the top and sides of a double-layer shield tunnel as described in claim 1, characterized in that, The fireproof and smoke-proof mechanism (16) includes two mounting bases (161), a guide roller (162) rotatably disposed between the two mounting bases (161), a take-up roller shaft (163), and a fireproof roller shutter (166) fixed and wound around the outer wall of the take-up roller shaft (163). The free end of the fireproof roller shutter (166) hangs down naturally after passing over the guide roller (162). A connecting cylinder (164) and an electromagnetic suction ring (167) are sleeved on the outer wall of the take-up roller shaft (163). The connecting cylinder (164) is fixed. The electromagnetic suction ring (167) is fixed inside the connecting cylinder (164) on the mounting base (161). The outer wall of the take-up roller shaft (163) is also fitted with a torsion spring (168) located inside the connecting cylinder (164). The two ends of the torsion spring (168) are fixedly connected to the inner wall of the take-up roller shaft (163) and the connecting cylinder (164) respectively, so that when the electromagnetic suction ring (167) is de-energized and released, the torsion spring (168) can drive the take-up roller shaft (163) to rotate and release the fireproof roller shutter (166).

4. The system for coordinated ventilation and smoke extraction at the top and sides of a double-layer shield tunnel as described in claim 3, characterized in that, The inner walls of the lower driving lane (2) and the upper driving lane (4) are also provided with a reset adjustment mechanism (17) for use with the fireproof and smoke-proof mechanism (16). The reset adjustment mechanism (17) includes a guide slide rail (171) fixedly installed on the side wall of the lane. A sliding block (172) is slidably installed in the guide slide rail (171). A drive motor II (176) is fixedly installed in the sliding block (172). A spline sleeve (179) is provided at the output end of the drive motor II (176) and can move axially. A spline shaft I (165) is fixed at one end of the winding roller shaft (163). When the spline sleeve (179) moves axially and engages with the spline shaft I (165), the drive motor II (176) can drive the winding roller shaft (163) to rotate through the spline sleeve (179) to wind up the fireproof roller shutter (166).

5. The system for coordinated ventilation and smoke extraction at the top and sides of a double-layer shield tunnel as described in claim 4, characterized in that, The sliding block (172) is fixedly equipped with a drive motor I (174), and the output end of the drive motor I (174) is fixedly fitted with a transmission gear (175). A rack guide rail (173) that meshes with the transmission gear (175) is fixedly provided on one side of the guide rail (171), so that the drive motor I (174) can drive the sliding block (172) to move along the guide rail (171).

6. The system for coordinated ventilation and smoke extraction at the top and sides of a double-layer shield tunnel as described in claim 5, characterized in that, The reset adjustment mechanism (17) further includes a fixed frame (177) fixed to one side of the sliding block (172) and a spline shaft II (178) fixedly sleeved on the output end of the drive motor II (176) and adapted to the spline teeth of the spline shaft I (165). The spline sleeve (179) is slidably sleeved on the spline shaft II (178). A sliding base plate (1710) is slidably arranged inside the fixed frame (177). The spline sleeve (179) passes through and is rotatably connected to the sliding base plate (1710). An electric push rod mechanism (1711) is fixedly installed on one side of the fixed frame (177). Its output end is connected to the sliding base plate (1710) and is used to push the sliding base plate (1710) and the spline sleeve (179) to move axially.

7. The system for coordinated ventilation and smoke extraction at the top and sides of a double-layer shield tunnel as described in claim 6, characterized in that, The output end of the electric push rod mechanism (1711) is rotatably connected to the sliding base plate (1710) through the connecting rod assembly (1712).

8. The system for coordinated ventilation and smoke extraction at the top and sides of a double-layer shield tunnel as described in claim 1, characterized in that, The lower level driving lane (2) and the upper level driving lane (4) are respectively provided with a lower level evacuation corridor (3) and an upper level evacuation corridor (5); the side walls of the lower level evacuation corridor (3) and the upper level evacuation corridor (5) are provided with multiple door openings that are connected to the lower level driving lane (2) and the upper level driving lane (4), and each door opening is provided with a fire door.

9. A smoke extraction method for a combined top and side ventilation and smoke extraction system for a double-layer shield tunnel, as described in any one of claims 1 to 8, characterized in that, Includes the following steps: S1. Determine the volumetric flow rate control mode for the air supply inlet and the smoke exhaust outlet; The volumetric flow rate control of both the air supply inlet and the smoke exhaust outlet can be solved based on the air volume and the opening angle of the regulating valve. In the formula: V se,i V represents the volumetric flow rate of each air inlet / exhaust outlet; f Supply air volume / exhaust air volume; θ i The opening angle of the regulating valve in the i-th air supply inlet / smoke exhaust outlet is n, and the number of openings is n. The air supply inlet is the free end of connecting pipe II (10) and connecting pipe III (11), and the smoke exhaust outlet is the free end of connecting pipe I (8) and smoke exhaust outlet (18). Regulating valves are installed on both the air supply inlet and the smoke exhaust outlet. The regulating valves are multiple rows of valve plates that are perpendicular to the horizontal direction of the tunnel and whose opening degree can be adjusted. S2. Determine the opening degree of the regulating valves at each air supply inlet and smoke exhaust outlet: The volumetric flow rate V of the i-th air supply inlet / smoke exhaust outlet se,i expression: In the formula: v i Let θ be the inflow velocity, α be the valve opening angle, and α be the angle between the inflow velocity and the horizontal direction. θi θ is the flow area when the regulating valve is open; a is the length of the regulating valve; h is the height of the regulating valve, which is the same as the height of the smoke exhaust outlet. During air supply, based on the energy changes in the flow process of "air supply duct - connecting pipe - tunnel", an energy equation is established, and the relationship between the flow velocity in the regulating valve at the i-th air supply inlet and the local resistance coefficient under the uniform volumetric flow rate mode is obtained as follows: During smoke exhaust, based on the energy changes in the flow process of "tunnel-connecting pipe-smoke exhaust duct", an energy equation is established, and the relationship between the smoke flow velocity in the regulating valve at the i-th smoke exhaust outlet and the local resistance coefficient is obtained as follows: In the formula: P se,i P is the static pressure inside the i-th air supply inlet / smoke exhaust outlet; sd,i P is the static pressure at the i-th air supply inlet / smoke exhaust outlet within the air supply duct / smoke exhaust duct; f The static pressure at the beginning of the air supply duct / the end of the smoke exhaust duct; λ sd The friction factor (λ) within the air supply / exhaust duct is calculated based on the surface roughness of the wall material. sp ζ is the friction coefficient of the air supply / exhaust duct connecting pipe; sd,i ζ is the local resistance coefficient within the supply air duct / exhaust air duct at the i-th supply air inlet / exhaust air outlet; sp,i The local resistance coefficient of the airflow within the i-th air supply inlet / exhaust outlet - connecting pipe - exhaust duct; L is the distance from the n-th air supply inlet / exhaust outlet to the beginning of the air supply duct / the end of the exhaust duct; x i D is the distance from the i-th air supply inlet / exhaust outlet to the beginning of the air supply duct / the end of the exhaust duct; sd D is the equivalent diameter of the air supply duct / smoke exhaust duct. sp ρ is the equivalent diameter of the air supply / exhaust duct connection pipe; a air density; ρ s This represents the density of the flue gas.

10. The method for coordinated ventilation and smoke extraction at the top and sides of a double-layer shield tunnel as described in claim 9, characterized in that, In step S2, the volumetric flow rate of each exhaust port is maximized during smoke discharge, and the opening degree of each regulating valve is determined according to the derivative method: 。

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