Urban subway construction method of first connecting a passage and then supporting a main tunnel

Abstract

The present application provides a kind of urban subway construction method of first contact channel and then shield main tunnel, comprising the following steps: step S1, the position, depth and size information of contact channel excavation are determined;Step S2, the shaft is excavated to the predetermined depth of contact channel, and the shaft support is constructed;Step S3, contact channel is excavated horizontally, and primary support is completed in the process of excavation;Step S4, shield main tunnel is constructed by shield machine, and temporary support of tunnel is constructed;Step S5, the construction of lining of contact channel is carried out, and the contact channel is reinforced.The present application provides a kind of urban subway construction method of first contact channel and then shield main tunnel, which adopts the mode of first constructing contact channel and then shield main tunnel, so that the main tunnel is not disturbed by the construction of contact channel, and the stability of main tunnel is ensured;Contact channel and shaft can be used as material transportation channel or safety channel, which is convenient for material transportation and personnel access during construction and emergency;And the convenience of multilayer channel construction is increased.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of urban rail transit, in particular to a kind of urban subway construction method of first contact passage then shield main tunnel. BACKGROUND

[0002] At present, in order to alleviate the ground traffic pressure and improve the travel environment of residents, and promote the prosperity and development of the whole society and economy, a large number of urban rail transit construction faces the challenge of construction technology problem. In order to ensure that the subway tunnel can evacuate passengers safely and quickly in emergency, a transverse connecting passage needs to be set between two subway tunnels, and the connecting passage can also play the role of tunnel drainage, fire prevention and other functions.

[0003] According to the provisions of "Subway Design Specification" (GB50157-2013), connecting passages should be set between two single-line interval tunnels, and the distance between adjacent two connecting passages should not be greater than 600m. For long-distance subway lines, the number of connecting passages is large and the cost is high.

[0004] At present, the construction method of urban subway interval connecting passage mainly adopts mine method, freezing method and mechanical method:

[0005] The mine method is to complete two single-line shield intervals, based on the new Austrian method, to excavate the connecting passage manually or mechanically, and to adopt steel arch initial support and concrete secondary lining construction method. This method has long construction period, low efficiency, high stratum reinforcement cost, certain influence on the surrounding environment and unfavorable working environment for construction personnel;

[0006] The freezing method is actually a variant of the mine method. Before manual excavation, the soil needs to be frozen to form a certain frozen circle. This method needs to consume a lot of freezing time and is not suitable for running water sand layer;

[0007] The mechanical method also needs to complete two single-line shield intervals, and uses a micro shield machine to break the pipe piece (using glass fiber reinforced steel) of the main tunnel, and then the shield is pushed until it penetrates the other side of the main tunnel. This method can only construct circular cross-section tunnels. For the connecting passage with water collecting well, the construction is limited. The stress and deformation of T-shaped joint structure of connecting passage and main tunnel structure are complex, and there are disadvantages such as water leakage.

[0008] As can be seen, whether it is mine method, freezing method or mechanical method, two shield main tunnels need to be penetrated before the construction of connecting passage, which leads to the increase of the whole construction period. At the same time, the construction of connecting passage will also disturb the main tunnel, and mechanical construction will also hinder the material transportation of the main tunnel.

[0009] Especially in the process of carrying out the construction of the multi-layer tunnel, the construction and connection of the connecting passage are more troublesome, and the material transportation and ventilation during the construction of the lower layer are more inconvenient;

[0010] And during the construction and after the completion of the construction, the emergency escape passage needs to be set, but the construction mode of the connecting passage after the main tunnel leads to less emergency passages, and additionally setting the two-layer or multi-layer passage also needs to be re-excavated, which is time-consuming and laborious. SUMMARY

[0011] The main purpose of the present application is to provide a city subway construction method of connecting passage first and shield main tunnel, which solves the problem of inconvenient construction caused by connecting passage after the construction of the main tunnel.

[0012] To solve the above technical problems, the technical scheme adopted by the present application is:

[0013] A city subway construction method of connecting passage first and shield main tunnel, comprising the following steps:

[0014] Step S1, determining the position, depth and size information of the connecting passage excavation;

[0015] Step S2, before the main tunnel excavation, excavating the vertical shaft to the predetermined depth of the connecting passage, and supporting the vertical shaft;

[0016] Step S3, excavating the connecting passage transversely and completing the primary support during the excavation;

[0017] Step S4, shield main tunnel by the shield machine, and support the temporary tunnel;

[0018] Step S5, constructing the lining of the connecting passage and reinforcing the connecting passage;

[0019] Through the above steps, the construction of the connecting passage is quickly completed.

[0020] In the preferred scheme, the primary support includes mortar anchor rod, grouting anchor rod and steel support, and the steel support is removed during the construction of the lining of the connecting passage.

[0021] In the preferred scheme, in step S3, it further comprises:

[0022] Step S31, expanding the trumpet mouth at the end of the connecting passage and supporting the shield area of the main tunnel;

[0023] Step S32, setting a temporary safety door between the trumpet mouth and the connecting passage;

[0024] Step S33, removing the support of the trumpet mouth and filling the position of the trumpet mouth with light foam concrete;

[0025] After step S4 is completed, the shield tunnel segments near the safety door are removed, then the safety door and temporary support are removed, and finally secondary lining construction is carried out for reinforcement.

[0026] In the preferred embodiment, during construction, a shaft opening transport machine is installed above the shaft for the entry and exit of construction materials and machinery, as well as the removal of excavated waste.

[0027] A construction hoist is installed inside the shaft for construction personnel to enter and exit.

[0028] In the preferred embodiment, during the tunnel boring process of the main tunnel, the required materials are delivered through the nearest connecting passage and shaft, and construction personnel can also enter and exit through the nearest connecting passage and shaft;

[0029] The construction of the main tunnel shield tunnel and the connecting passage is 1-2 construction periods apart. That is, the connecting passage is constructed sequentially according to the route, and the main tunnel shield tunneling begins after the first connecting passage is completed.

[0030] In the preferred embodiment, the location of the underground shaft is laterally offset from the predetermined position. After being excavated to a sufficient depth, a transfer channel is excavated laterally to the predetermined position of the connecting channel, and then the horizontal excavation of the connecting channel continues.

[0031] After construction is completed, a prefabricated emergency passage connecting the transfer channel and the ground will be erected in the shaft as needed, and emergency doors that can be opened in an emergency will be set at both ends of the prefabricated emergency passage.

[0032] In the preferred embodiment, a protective door is installed at the connection between the transfer channel and the communication channel;

[0033] Storage rooms were dug inside the transfer channel to store emergency rescue tools and construction materials.

[0034] In the preferred embodiment, the excavation continues at the location of the shaft until the excavation position of the second-level main tunnel is reached. Shaft support is then constructed, and steps S3, S4, and S5 are repeated to complete the construction of the second-level tunnel. The construction of the second-level tunnel does not affect the tunnel that has already been completed.

[0035] In the preferred embodiment, an emergency passage is excavated at an angle between the transfer passage and the ground, and emergency doors that can be opened in an emergency are set at both ends of the emergency passage;

[0036] The emergency exit connects to the vertical shaft, which serves as a ventilation channel.

[0037] In the preferred embodiment, after construction is completed, the step of setting up a prefabricated emergency passage is also included:

[0038] Step S61: Based on the depth of the shaft, use a crane to lower multiple pipes. Ladders are installed inside the pipes, and the ladders in adjacent pipes are connected.

[0039] Step S62, a first door hole is opened at the joint of the pipe cylinder and the transfer channel;

[0040] Step S63, a pipe cover is covered on the uppermost pipe cylinder, the pipe cover is not less than 3 meters away from the ground, and the shaft is backfilled;

[0041] Step S64, a safety channel is dug from the ground side to the bottom of the pipe cover, a second door hole is opened at the joint of the pipe cover and the safety channel, and the second door hole is connected with the ladder;

[0042] Step S65, emergency doors are constructed at the first door hole and the second door hole;

[0043] Among them, the side of the pipe cylinder connected with the connecting channel is provided with a first door hole, the side of the pipe cover is provided with a second door hole, the inner wall of the pipe cylinder is provided with a spiral ladder, the uppermost of the ladder in the same pipe cylinder is provided with a platform, the end of the ladder and the platform away from the inner wall of the pipe cylinder is provided with a railing, the platform is connected with the ladder between the adjacent two pipe cylinders, the first door hole is connected with the ladder, and the second door hole is connected with the platform;

[0044] The inner wall bottom end of the pipe cylinder and the pipe cover is fixed with a plug-in pipe, and the plug-in pipe is inserted into the lower pipe cylinder;

[0045] The inner wall top end of the pipe cylinder and the top end of the pipe cover are fixed with a connecting ring for hoisting;

[0046] The outer side wall of the pipe cylinder and the pipe cover is provided with a corrosion-resistant coating.

[0047] In the preferred scheme, the shaft position is continuously dug to reach the excavation position of the second layer main tunnel, and then steps S3, S4 and S5 are repeated to complete the construction of the second layer tunnel;

[0048] When the second layer tunnel is constructed, if it is constructed at the same time as the first layer tunnel, the emergency channel is constructed after the connecting channel and the main tunnel at the same shaft position are completed;

[0049] If the second layer channel is added later, the backfill on the pipe cover is dug, then the pipe cover and the pipe cylinder are lifted one by one, and then the second layer excavation construction is continued, and the emergency channel is constructed again after completion.

[0050] The application provides a city subway construction method of first connecting channel and then shield main tunnel, and has the beneficial effects that:

[0051] 1. The method of first constructing the connecting channel and then constructing the main tunnel does not disturb the main tunnel due to the construction of the connecting channel, so that the stability of the main tunnel is ensured.

[0052] 2. The connecting channel and the shaft can be used as a channel for material transportation or a safety channel, which is convenient for material transportation and personnel access during construction and emergency, and can also be used as a ventilation channel.

[0053] 3. The prefabricated emergency passage is simple to set up, has higher construction efficiency, and is convenient for personnel to enter and exit.

[0054] 4. The application facilitates simultaneous construction of the multi-layer connecting passage and the shield main tunnel, and facilitates later addition of the multi-layer connecting passage and the shield main tunnel, thereby increasing the convenience of multi-layer passage construction and solving the problem of inconvenient construction of multi-layer tunnels. BRIEF DESCRIPTION OF DRAWINGS

[0055] The application will be further described below in combination with the drawings and embodiments:

[0056] Figure 1 is a structural schematic view of a one-layer tunnel after construction according to the urban subway construction method of the application, in which a connecting passage is first constructed and then a shield main tunnel is constructed;

[0057] Figure 2 is a structural schematic view of a two-layer tunnel after construction according to the urban subway construction method of the application, in which a connecting passage is first constructed and then a shield main tunnel is constructed;

[0058] Figure 3 is a structural schematic view of a connecting passage after construction according to the application;

[0059] Figure 4 is a structural schematic view of a main passage shield according to the application;

[0060] Figure 5 is a structural schematic view of an embodiment of a connecting passage according to the application;

[0061] Figure 6 is a structural schematic view of a prefabricated emergency passage according to the application;

[0062] Figure 7 is a structural schematic view of a prefabricated emergency passage according to the application;

[0063] Figure 8 is a structural schematic view of a prefabricated emergency passage according to the application;

[0064] Figure 9 is a structural schematic view of a prefabricated emergency passage according to the application;

[0065] Figure 10 is a structural schematic view of a prefabricated emergency passage according to the application;

[0066] Figure 11 is a structural schematic view of an embodiment of an emergency passage according to the application;

[0067] Figure 12 is a schematic view of hoisting of a prefabricated emergency passage according to the application.

[0068] In the drawings: In the drawings:

[0069] Pipe barrel 1, first door hole 101, pipe cover 2, second door hole 201, ladder 3, platform 4, railing 5, plug pipe 6, connecting ring 7;

[0070] Shaft 11, shaft support 12, steel support 13, initial support 14, shaft transport machinery 15, safety door 16, trumpet mouth 17, light foam concrete 18, main tunnel 20, temporary support 21, lining 22, connecting passage 30, first floor connecting passage axis 41, second floor connecting passage axis 42, transfer passage 50. DETAILED DESCRIPTION

[0071] Embodiment 1

[0072] As shown in Figure 1 , 3 and 4, a city subway construction method of connecting passage first and shield main tunnel, comprising the following steps:

[0073] Step S1, determining the position, depth and size information of the connecting passage 30 excavation;

[0074] Step S2, before the main tunnel 20 excavation, the shaft 11 is excavated to the predetermined depth of the connecting passage 30, and the shaft support 12 is constructed;

[0075] Step S3, excavate the connecting passage 30 transversely, and complete the initial support 14 during the excavation process;

[0076] Step S4, shield the main tunnel 20 by shield machine, and construct the tunnel temporary support 21;

[0077] Step S5, the connecting passage 30 is constructed with lining 22, and the connecting passage 30 is reinforced;

[0078] Through the above steps, the construction of the connecting passage 30 is quickly completed.

[0079] The first floor connecting passage axis 41 and the second floor connecting passage axis 42 are used to illustrate the excavation position of the connecting passage, and the specific position is determined according to the actual situation.

[0080] During the construction process, by the way of connecting passage 30 first and main tunnel 20 later, the main tunnel 20 is formed later, which will not be disturbed by the construction of the connecting passage 30, and the connecting passage 30 can be used as a material transportation and ventilation passage, which is more convenient during the construction of the main tunnel 20.

[0081] In the preferred scheme, the initial support 14 includes mortar anchor rod, grouting anchor rod and steel support 13, and the steel support 13 is removed during the construction of the lining 22 of the connecting passage 30.

[0082] In the preferred scheme, in step S3, it further comprises:

[0083] Step S31, the trumpet 17 is expanded and supported at the end of the main tunnel 20 shield area of the connecting channel 30, and the trumpet 17 is in the shield range of the main tunnel 20, and the shield machine shield passes through the trumpet 17;

[0084] Step S32, a temporary safety door 16 is arranged between the trumpet 17 and the connecting channel 30;

[0085] Step S33, the support of the trumpet 17 is removed, and the light foam concrete 18 is filled at the position of the trumpet 17 for reinforcement, and the safety door 16 can seal the light foam concrete 18;

[0086] After step S4 is completed, the shield segment near the safety door 16 is removed, then the safety door 16 and the temporary support 21 are removed, and finally the secondary lining construction is carried out for reinforcement.

[0087] By using the reinforcement method of foam concrete 18, the support effect can be guaranteed, and subsequent processing can be facilitated, such as facilitating subsequent shield processing.

[0088] In the preferred scheme, a shaft head transport machine 15 is arranged above the shaft 11 during construction, which includes a gantry crane or an elevator, etc., which is used for the entry and exit of construction materials and machines and the transportation of excavation waste, greatly shortening the transportation distance;

[0089] A construction elevator is arranged in the shaft 11 for the entry and exit of construction personnel.

[0090] During subsequent construction, construction personnel can choose to enter and exit through the shaft with the elevator arranged therein, so that the entry and exit of construction personnel into the tunnel can be more convenient, and they can return to the ground faster in case of an accident.

[0091] In the preferred scheme, during the construction of the main tunnel 20, the required materials are sent in through the nearest connecting channel 30 and shaft 11, and the construction personnel can also enter and exit through the nearest connecting channel 30 and shaft 11;

[0092] The construction of the main tunnel 20 shield and the connecting channel 30 is different by 1-2 construction periods, that is, the connecting channel 30 is constructed in sequence according to the line, and the main tunnel 20 shield starts after the first connecting channel 30 is constructed, and then the subsequent connecting channels 30 are constructed in sequence, so that the efficiency of construction is ensured while ensuring that the connecting channel 30 is constructed first and then the main tunnel 20 shield.

[0093] Embodiment 2:

[0094] As Figure 5As shown, the position of the excavated shaft 11 is laterally offset at the predetermined position, and after being excavated to a sufficient depth, the transfer channel 50 is excavated laterally to the predetermined position of the connecting channel 30, and then the connecting channel 30 is continuously excavated laterally;

[0095] After the construction is completed, according to the needs, a prefabricated emergency channel is erected in the shaft 11 to connect the transfer channel 50 and the ground, and emergency doors are arranged at both ends of the prefabricated emergency channel to be opened in an emergency.

[0096] By arranging the transfer channel 50, the shaft 11 can be avoided to be directly connected with the connecting channel 30, the safety is higher in subsequent construction, and the influence of the construction of the connecting channel 30 on the shaft 11 can be reduced, and the transfer channel 50 also plays a role of transfer;

[0097] After the prefabricated emergency channel is erected, the use of the connection is not affected in normal times, and the prefabricated emergency channel is directly accessed in an emergency.

[0098] In the preferred scheme, a protective door is arranged at the connection between the transfer channel 50 and the connecting channel 30, the transfer channel 50 and the connecting channel 30 are isolated in normal times, only necessary ventilation holes are left, the protective door is opened when needed, and the protective door can be arranged in reference to a fire door;

[0099] A storage room is arranged in the transfer channel 50 for storing emergency rescue tools and construction materials, and the fixed storage room can facilitate the nearby emergency at any time.

[0100] Embodiment 3:

[0101] As shown in the figure, Figure 2 the shaft 11 is continuously excavated to the excavation position of the second layer tunnel 20, the shaft support 12 is constructed, and then steps S3, S4 and S5 are repeated to complete the construction of the second layer tunnel, and the construction of the second layer tunnel does not affect the constructed tunnel;

[0102] When the second layer tunnel is constructed, if it is constructed at the same time period as the first layer tunnel, the connecting channel 30 and the main tunnel 20 at the same position of the shaft 11 are completed, and then the emergency channel is constructed.

[0103] By the method of the present application, the construction of double-layer or even multi-layer tunnels is facilitated, the transportation of materials is more convenient, the use of the upper tunnel is not affected, and additional excavation positions are not needed, thereby adapting to the construction requirements of multi-layer tunnels, and solving the problem that multi-layer tunnel construction is not convenient in the prior art.

[0104] Embodiment 4:

[0105] As shown in the figure, Figure 6 , 7, 8, 9, 10 and 12, after the construction is completed, further comprising the step of setting a prefabricated emergency passage:

[0106] Step S61, according to the depth of the shaft 11, a plurality of pipe cylinders 1 are lowered using a crane, a ladder is arranged in each pipe cylinder 1, and the ladders in adjacent pipe cylinders 1 are connected;

[0107] Step S62, a first door hole 201 is arranged at the joint of the pipe cylinder 1 and the transfer passage 50;

[0108] Step S63, a pipe cover 2 is arranged above the uppermost pipe cylinder 1, the distance between the pipe cover 2 and the ground is not less than 3 meters, and the shaft 11 is backfilled;

[0109] Step S64, a safety passage is dug from the ground side to the bottom of the pipe cover 2, a second door hole 202 is arranged at the joint of the pipe cover 2 and the safety passage, and the second door hole 202 is connected with the ladder;

[0110] Step S65, emergency doors are arranged at the first door hole 201 and the second door hole 202;

[0111] The pipe cylinder 1 connected with the communication passage 30 is provided with a first door hole 101 on the side, the pipe cover 2 is provided with a second door hole 201 on the side, the inner wall of the pipe cylinder 1 is provided with a spiral-shaped ladder 3, the uppermost part of the ladder 3 in the same pipe cylinder 1 is provided with a platform 4, the ladder 3 and the platform 4 are provided with a handrail 5 at the end away from the inner wall of the pipe cylinder 1, the platform 4 is connected with the ladder 3 between two adjacent pipe cylinders 1, the first door hole 101 is connected with the ladder 3, and the second door hole 201 is connected with the platform 4;

[0112] The inner wall of the pipe cylinder 1 and the inner wall of the pipe cover 2 are both fixed with a plug pipe 6, and the plug pipe 6 is inserted into the pipe cylinder 1 below;

[0113] The inner wall of the pipe cylinder 1 and the top of the pipe cover 2 are both fixed with a connecting ring 7 for hoisting;

[0114] The outer wall of the pipe cylinder 1 and the outer wall of the pipe cover 2 are both provided with a corrosion-resistant coating.

[0115] In use, the user reaches the transfer passage 50 through the communication passage 30, then walks to the ladder 3 through the first door hole 101, then climbs up along the ladder 3, and finally walks out through the second door hole 201.

[0116] After the user walks out through the second door hole 201, the user can walk back to the ground through the safety passage.

[0117] The whole installation process is carried out by hoisting, which is convenient and more efficient than the prior art.

[0118] If the second layer passage needs to be added later, the backfill on the pipe cover 2 is dug out, then the pipe cover 2 and the pipe barrel 1 are lifted one by one, and then the second layer excavation construction is continued, and after completion, the emergency passage is re-constructed. When adding, it does not need to be damaged, and after being directly taken out, it can be used twice, reducing waste.

[0119] Embodiment 5:

[0120] As shown in Figure 11 , the emergency passage is obliquely excavated between the transfer passage 50 and the ground, emergency doors are arranged at both ends of the emergency passage to be opened in an emergency, the emergency passage is constructed by drilling and blasting, or is excavated by a self-unloading excavator, or is constructed by pipe jacking, the height of the emergency passage is not less than 2 meters, and is preferably 2.5 meters, a ladder or an escalator or an elevator is arranged in the emergency passage according to construction requirements; the emergency passage is connected to the shaft 11, and the shaft 11 serves as a ventilation passage.

[0121] In the construction of the second layer tunnel, the shaft 11 is directly continued to be excavated, and then steps S3, S4 and S5 are repeated to complete the construction of the second layer tunnel, and in this process, the emergency passage is not affected, the emergency passage of the second layer tunnel is obliquely excavated and connected to the upper emergency passage, and the emergency passage can be excavated in a Z shape.

[0122] The present application is applied to the construction of urban metro, but is not limited to the construction of urban metro

[0123] The above-described embodiments are only preferred technical solutions of the present application, and should not be regarded as a limitation of the present application, the protection scope of the present application should be the technical solutions recited in the claims, including the equivalent replacement solutions of the technical features recited in the claims as the protection scope. That is, the equivalent replacement improvement within this range is also within the protection scope of the present application.

Claims

1. A method for constructing urban subways by first establishing connecting passages and then tunneling the main shield tunnel, characterized by: It comprises the following steps: Step S1, determining the position, depth and size information of the excavation of the connecting passage (30); Step S2, before the excavation of the main tunnel (20), the shaft (11) is excavated to the predetermined depth of the connecting passage (30), and the shaft support (12) is constructed; Step S3, the connecting passage (30) is excavated transversely, and the primary support (14) is completed during the excavation; Step S4, the shield machine excavates the main tunnel (20), and the temporary tunnel support (21) is constructed; Step S5, the connecting passage (30) is lined (22) to reinforce the connecting passage (30); Through the above steps, the construction of the connecting passage (30) is quickly completed; The position of the excavated shaft (11) is laterally offset at the predetermined position, and after being excavated to a sufficient depth, the transfer passage (50) is excavated transversely to the predetermined position of the connecting passage (30), and then the connecting passage (30) is further excavated transversely; After the construction is completed, according to the needs, a prefabricated emergency passage is erected in the shaft (11) to connect the transfer passage (50) and the ground, and emergency doors are provided at both ends of the prefabricated emergency passage for opening in emergency; A protective door is provided at the connection between the transfer passage (50) and the connecting passage (30); A storage room is excavated in the transfer passage (50) for storing emergency rescue tools and construction materials; After the construction is completed, the step of providing the prefabricated emergency passage is further included: Step S61, according to the depth of the shaft (11), a plurality of pipe cylinders (1) are lowered by a crane, the pipe cylinders (1) are provided with ladders inside, and the ladders inside the adjacent pipe cylinders (1) are connected; Step S62, a first door hole (201) is formed at the junction of the pipe cylinder (1) and the transfer passage (50); Step S63, a pipe cover (2) is placed above the uppermost pipe cylinder (1), the distance from the pipe cover (2) to the ground is not less than 3 meters, and the shaft (11) is backfilled; Step S64, a safety passage is excavated from the ground side to the bottom of the pipe cover (2), a second door hole (202) is formed at the connection between the pipe cover (2) and the safety passage, and the second door hole (202) is connected with the ladder; Step S65, emergency doors are constructed at the first door hole (201) and the second door hole (202); The side of the pipe cylinder (1) connected with the connecting passage (30) is provided with a first door hole (101), the side of the pipe cover (2) is provided with a second door hole (201), the inner wall of the pipe cylinder (1) is provided with a spiral ladder (3), the uppermost of the ladders (3) in the same pipe cylinder (1) is provided with a platform (4), the end of the ladder (3) and the platform (4) away from the inner wall of the pipe cylinder (1) is provided with a railing (5), the platform (4) is connected with the ladder (3) between the adjacent two pipe cylinders (1), the first door hole (101) is connected with the ladder (3), and the second door hole (201) is connected with the platform (4); The inner wall bottom end of the pipe cylinder (1) and the pipe cover (2) is fixed with a plug-in pipe (6), and the plug-in pipe (6) is inserted into the lower pipe cylinder (1); The inner wall top end of the pipe cylinder (1) and the top end of the pipe cover (2) are fixed with a connecting ring (7) for hoisting; The outer side wall of the pipe cylinder (1) and the pipe cover (2) is provided with a corrosion-resistant coating.

2. The method according to claim 1, characterized in that: The initial support (14) includes mortar anchor, grouting anchor and steel support (13), and the steel support (13) is removed when the lining (22) of the connecting passage (30) is constructed.

3. The method according to claim 1, wherein the method further comprises the step of: In step S3, the following steps are further included: ​ In step S31, the trumpet (17) is expanded and supported at the shield area of the main tunnel (20) at the end of the connecting passage (30); In step S32, a temporary safety door (16) is constructed between the trumpet (17) and the connecting passage (30); In step S33, the support of the trumpet (17) is removed, and the trumpet (17) is filled with light foam concrete (18). After step S4 is completed, the shield segment near the safety door (16) is removed, and then the safety door (16) and the temporary support (21) are removed, and finally the secondary lining construction is carried out for reinforcement.

4. The method according to claim 1, characterized in that: During the construction, the shaft head transport machinery (15) is arranged above the shaft (11) for the entry and exit of construction materials and machinery and the transportation of excavation waste; The construction elevator is arranged in the shaft (11) for the entry and exit of construction personnel.

5. The method according to claim 1, wherein the method is characterized in that: During the shield construction of the main tunnel (20), the required materials are sent in through the nearest connecting passage (30) and shaft (11), and the construction personnel can also enter and exit through the nearest connecting passage (30) and shaft (11); The shield construction of the main tunnel (20) is 1-2 construction periods different from the connecting passage (30), that is, the connecting passage (30) is constructed according to the line in sequence, and the shield construction of the main tunnel (20) starts after the first connecting passage (30) is constructed.

6. The method according to claim 1, wherein the method is characterized in that: The shaft (11) is continuously excavated to the excavation position of the second layer main tunnel (20), the shaft support (12) is constructed, and then steps S3, S4 and S5 are repeated to complete the construction of the second layer tunnel, which does not affect the constructed tunnel.

7. The urban subway construction method according to claim 6, which involves first constructing a connecting passage and then a shield tunnel, is characterized in that: in The inclined emergency passage between the transfer passage (50) and the ground is excavated, and the emergency doors are arranged at both ends of the emergency passage and opened in emergency; The emergency passage is connected to the shaft (11), and the shaft (11) serves as a ventilation passage.

8. The method according to claim 1, characterized in that: The shaft (11) is continuously excavated to the excavation position of the second layer main tunnel (20), and then steps S3, S4 and S5 are repeated to complete the construction of the second layer tunnel; When the second layer tunnel is constructed, if it is constructed in the same period as the first layer tunnel, the emergency passage is constructed after the connecting passage (30) and the main tunnel (20) at the same shaft (11) position are both completed; If the second layer passage is added later, the backfill on the pipe cover (2) is excavated, then the pipe cover (2) and the pipe cylinder (1) are lifted one by one, and then the second layer excavation construction is continued, and after completion, the emergency passage is reconstructed.

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