A diversion tunnel shaft excavation and support system and its usage method

Abstract

The present invention discloses a diversion tunnel shaft excavation and support system, including a shaft tunnel. An expansion opening is provided at the ground end of the shaft tunnel. A clamping edge circular frame is installed on the expansion opening. One side of the clamping edge circular frame is welded with a support plate. A first reinforced concrete layer is poured on one side of the support plate. A number of fixed steel grooves are installed on the ground end, and a number of mounting plates are welded on the fixed steel grooves; a second reinforced concrete layer for spraying is provided inside the upper end of the shaft tunnel, and a waterproof layer is provided inside the second reinforced concrete layer; its usage method includes: S1. Excavate the expansion opening; S2. Fix and install the clamping edge circular frame; S3. Pour the first reinforced concrete layer and lay a gravel layer; S4. Lay the fixed steel grooves on the upper part of the gravel layer; S5. Operate through a raise boring machine and a winch. The present invention can install and fix equipment, effectively prevent the collapse of the inner wall of the shaft, and conduct connection fixation and waterproof treatment on the inner wall concrete.

Description

Technical Field:

[0001] The present invention belongs to the technical field of diversion tunnels, and particularly relates to a support system for the excavation of a diversion tunnel shaft. Background Art:

[0002] A diversion tunnel refers to a tunnel used for the purpose of construction diversion. Tunnel diversion is mainly applicable to mountain rivers with narrow river valleys, steep banks and firm rocks. A diversion tunnel is a temporary engineering structure. One of its characteristics is that the construction period is often very urgent. If it cannot be completed on schedule, it will cause the extension of the entire project's construction period. During the construction period, the original river flow is diverted from the upstream cofferdam to the tunnel behind the downstream cofferdam. However, there are still various problems with various support systems on the market.

[0003] For example, as disclosed in a shaft excavation method adaptable to geology and its shaft tunneling machine support system with the authorization publication number CN113530551A, although it realizes the real-time measurement of the soil pressure of the shaft during the excavation process through a soil pressure measuring device, and after obtaining the corresponding bolt support parameters, the side wall of the shaft is supported, avoiding the problem that in the past, geological exploration needed to be carried out first before the excavation of a deep shaft to obtain the corresponding bolt support parameters, which consumed a lot of manpower and material resources and the exploration was inaccurate during the whole exploration process. However, it does not solve the problems that the existing upper ground cannot effectively install and fix the equipment, cannot effectively prevent the collapse of the inner wall of the shaft, and cannot realize the connection fixation and waterproof treatment of the inner wall concrete. Therefore, we propose a support system for the excavation of a diversion tunnel shaft. Summary of the Invention:

[0004] The purpose of the present invention is to provide a support system for the excavation of a diversion tunnel shaft to solve the problems raised in the above background art.

[0005] To achieve the above purpose, the present invention provides the following technical solution: A support system for the excavation of a diversion tunnel shaft, including a shaft tunnel. An expansion port is opened at the ground end of the shaft tunnel. A clamping circular frame is fixedly installed on the expansion port. A support plate is welded to one side of the clamping circular frame. A first reinforced concrete layer is poured on one side of the support plate. A number of fixed steel grooves are fixedly installed on the ground end, and a number of mounting plates are welded on the fixed steel grooves;

[0006] A second reinforced concrete layer for spraying is provided inside the upper end of the shaft tunnel. A waterproof layer is provided inside the second reinforced concrete layer. A third reinforced concrete layer for spraying is provided inside the waterproof layer;

[0007] A clamping circular ring groove is opened inside the lower end of the shaft tunnel. A fixed frame is embedded and installed inside the clamping circular ring groove. A wooden square frame is fixedly connected inside the fixed frame.

[0008] Preferably, the card-edge circular frame is set in an L-shaped arc shape. The upper side plate of the card-edge circular frame is snap-connected to the upper side of the expansion port, the lower side plate of the card-edge circular frame is snap-connected to the inner wall of the shaft tunnel, and both side plates of the card-edge circular frame are fixedly installed by a number of first countersunk drill rods.

[0009] Preferably, a gravel layer is laid on the first reinforced concrete layer and the ground end. A number of the fixed steel grooves are provided on the upper surface of the gravel layer. A number of the fixed steel grooves are connected by second countersunk drill rods. The inner second countersunk drill rods are sequentially penetrated and connected in the gravel layer, the first reinforced concrete layer and the soil layer, and the outer second countersunk drill rods are sequentially penetrated and connected in the gravel layer and the soil layer.

[0010] Preferably, a number of snap-fit circular grooves are provided on the entire shaft wall of the shaft tunnel. The snap-fit circular grooves at the upper end of the shaft tunnel are also poured with a second reinforced concrete layer. The snap-fit circular grooves are vertically arranged circumferentially, and there are four snap-fit circular grooves arranged circumferentially.

[0011] Preferably, the fixed frame is in an arc shape. At least four of the fixed frames are inlaid and installed inside the snap-fit circular grooves. A number of the fixed frames are fixedly connected by connecting bolts. A wooden square frame is installed on the inner wall at the bottom of the shaft tunnel. The wooden square frame is fixedly connected to the fixed frame by connecting bolts. A number of square holes are provided on the wooden square frame.

[0012] Preferably, a power supply module for power supply operation is electrically connected to the control module. A data module is electrically connected to the control module. A pressure sensor is electrically connected to the data module. A comparison module is electrically connected to the data module. The comparison module is electrically connected to the control module. A drive module is electrically connected to the control module. An alarm module is electrically connected to the drive module. The pressure sensor is installed inside the wooden square frame and the card-edge circular frame.

[0013] Preferably, a support ring plate is fixedly inlaid in the middle of the shaft tunnel. The support ring plate is located below the second reinforced concrete layer, the waterproof layer and the third reinforced concrete layer. The support ring plate is in a semi-circular arc shape.

[0014] Preferably, a number of horizontal or vertical mounting plates are welded on the fixed steel grooves. The mounting plates are used to fixedly install the raise boring machine and the winch.

[0015] Preferably, the system includes the following usage method:

[0016] S1. Excavate the expansion opening: Excavate the expansion opening outside the selected point of the shaft. After excavating the expansion opening, then excavate the diameter opening of the shaft tunnel.

[0017] S2. Fix and install the clamping edge circular frame: After excavating the diameter opening, then fit the clamping edge circular frame to the inner wall of the shaft tunnel and the upper part of the expansion opening, and then fix and install both sides through the first countersunk drill rod.

[0018] S3. Pour the first layer of reinforced concrete and lay the gravel layer: After the clamping edge circular frame is installed and fixed, then pour the first layer of reinforced concrete at the edge of the expansion opening, and then lay the gravel layer on the first layer of reinforced concrete and the ground end.

[0019] S4. Lay and fix the steel trough on the upper part of the gravel layer: Fix and lay the steel trough on the gravel layer, and then fix and install it through the second countersunk drill rod. And several horizontal or vertical mounting plates are welded on the steel trough, and the raise boring machine and the hoist are fixed and installed through the mounting plates.

[0020] S5. Operate through the raise boring machine and the hoist: Fix and install the raise boring machine on the mounting plate to realize the construction of the reverse pilot shaft. After the construction of the reverse pilot shaft is completed, remove the raise boring machine, and then install the hoist to realize the hoisting of the lifting tool, so that the workers use the leg-mounted pneumatic drill for construction operations.

[0021] Preferably, during the construction process of the leg-mounted pneumatic drill, several clamping circular grooves are opened on the inner wall of the excavated shaft tunnel for pouring and installation connection. And the wooden square frame is installed first to prevent landslides and protect safety. Then the wooden square frame is removed, and the second layer of reinforced concrete, the waterproof layer and the third layer of reinforced concrete are sprayed on the inner wall of the shaft tunnel to form a complete shaft tunnel.

[0022] Compared with the prior art, the beneficial effects of the present invention are:

[0023] When the present invention is used, an expansion opening is provided to realize the end setting of the shaft tunnel, and the clamping edge circular frame is used to keep the end flat and safe, prevent the end from collapsing, and the expansion opening is blocked by a support plate, and pouring and the laying of the gravel layer are carried out, which is convenient for the installation of the fixed steel trough, so that the ground is convenient for installing equipment, effectively realizing the excavation of the shaft tunnel, and during the excavation process, the fixed frame is installed through the clamping circular groove, and the wooden square frame is installed and fixed through the fixed frame to keep the shaft tunnel safe. Then, the inner wall of the shaft tunnel is treated with reinforced concrete pouring by spraying, so as to realize the support for the excavation of the shaft tunnel and keep the shaft tunnel from collapsing or other dangerous accidents. Brief Description of the Drawings:

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0025] Figure 1 It is a schematic cross-sectional structure diagram of the present invention;

[0026] Figure 2 For the present invention Figure 1 An enlarged schematic view of part A in

[0027] Figure 3 For the present invention Figure 1 An enlarged schematic view of part B in

[0028] Figure 4 For the present invention Figure 1 An enlarged schematic view of part C in

[0029] Figure 5 It is a schematic flow chart of the steps of the present invention;

[0030] Figure 6 It is a schematic diagram of the system detection of the present invention.

[0031] In the figure: 1, vertical shaft; 2, expansion port; 3, card edge circular frame; 4, first countersunk drill rod; 5, support plate; 6, first reinforced concrete layer; 7, gravel layer; 8, fixed steel groove; 9, mounting plate; 10, clamping ring groove; 11, second reinforced concrete layer; 12, waterproof layer; 13, third reinforced concrete layer; 14, fixed frame; 15, wooden square frame; 16, connecting bolt; 17, second countersunk drill rod; 18, support ring plate. Detailed Embodiments:

[0032] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0033] Please refer to Figures 1-6, the present invention provides a technical solution: a diversion tunnel shaft excavation and support system, including a shaft tunnel 1, an expansion opening 2 is provided at the ground end of the shaft tunnel 1, a clamping edge circular frame 3 is fixedly installed on the expansion opening 2, a support plate 5 is welded to one side of the clamping edge circular frame 3, a first reinforced concrete layer 6 is poured on one side of the support plate 5, a plurality of fixed steel grooves 8 are fixedly installed on the ground end, and a plurality of mounting plates 9 are welded on the fixed steel grooves 8;

[0034] A second reinforced concrete layer 11 for spraying is provided inside the upper end of the shaft tunnel 1, a waterproof layer 12 is provided inside the second reinforced concrete layer 11, and a third reinforced concrete layer 13 for spraying is provided inside the waterproof layer 12;

[0035] A clamping ring groove 10 is provided inside the lower end of the shaft tunnel 1, a fixed frame 14 is embedded and installed inside the clamping ring groove 10, and a wooden square frame 15 is fixedly connected inside the fixed frame 14.

[0036] In order to achieve safety protection for the expansion opening 2, prevent collapse in the upper part, and achieve stable fixed installation of the clamping edge circular frame 3, in this embodiment, preferably, the clamping edge circular frame 3 is set in an L-shaped arc shape, the upper side plate of the clamping edge circular frame 3 is clamped and connected to the upper side of the expansion opening 2, the lower side plate of the clamping edge circular frame 3 is clamped and connected to the inner wall of the shaft tunnel 1, and both side plates of the clamping edge circular frame 3 are fixedly installed through a plurality of first countersunk drill rods 4.

[0037] In order to install the connection equipment on the ground, that is, install the excavation equipment and hoisting equipment through the fixed steel grooves 8 and maintain the stability of the installation, in this embodiment, preferably, a gravel layer 7 is laid on the first reinforced concrete layer 6 and the ground end, a plurality of the fixed steel grooves 8 are provided on the upper surface of the gravel layer 7, and a plurality of the fixed steel grooves 8 are connected through second countersunk drill rods 17. The inner second countersunk drill rods 17 are sequentially penetrated and connected in the gravel layer 7, the first reinforced concrete layer 6 and the soil layer, and the outer second countersunk drill rods 17 are sequentially penetrated and connected in the gravel layer 7 and the soil layer.

[0038] In order to facilitate installation and connection, a clamping ring groove 10 is provided, and the setting of the clamping ring groove 10 facilitates the connection of the second reinforced concrete layer 11 and maintains stability. In this embodiment, preferably, a plurality of clamping ring grooves 10 are provided on the entire shaft wall of the shaft tunnel 1, the second reinforced concrete layer 11 is also poured in the clamping ring groove 10 at the upper end of the shaft tunnel 1, the clamping ring grooves 10 are arranged vertically in a circumferential direction, and the clamping ring grooves 10 are arranged in four in a circumferential direction.

[0039] To facilitate the installation and fixation of the fixed frame 14, it is segmented and connected by connecting bolts 16 to maintain integrity. In this embodiment, preferably, the fixed frame 14 is arc-shaped, and at least four of the fixed frames 14 are inlaid and installed inside the clamping circular ring groove 10. The plurality of fixed frames 14 are fixedly connected by connecting bolts 16. To achieve safety protection for the shaft 1, prevent cave-ins, and facilitate excavation operations, a wooden square frame 15 is installed on the inner wall of the bottom of the shaft 1. The wooden square frame 15 is fixedly connected to the fixed frame 14 by connecting bolts 16, and a plurality of square holes are provided on the wooden square frame 15.

[0040] To detect the diversion shaft and achieve alarm, in this embodiment, preferably, a power supply module for power supply operation is electrically connected to the control module. A data module is electrically connected to the control module. The data module is used to process data information. A pressure sensor is electrically connected to the data module. The pressure sensor is used to detect pressure. A comparison module is electrically connected to the data module. The comparison module is electrically connected to the control module. The comparison module is used to compare the threshold value with the collected value. A drive module is electrically connected to the control module. An alarm module is electrically connected to the drive module. The alarm module is used to remind of abnormal data information. The pressure sensor is installed inside the wooden square frame 15 and the clamping circular frame 3.

[0041] To support the second reinforced concrete layer 11, the waterproof layer 12, and the third reinforced concrete layer 13 during pouring and to facilitate installation, a segmented setting is adopted. In this embodiment, preferably, a support ring plate 18 is fixedly inlaid in the middle of the shaft 1. The support ring plate 18 is located below the second reinforced concrete layer 11, the waterproof layer 12, and the third reinforced concrete layer 13, and the support ring plate 18 is semicircularly arranged.

[0042] To facilitate the installation and fixation of equipment on the fixed steel groove 8, in this embodiment, preferably, a plurality of horizontal or vertical mounting plates 9 are welded on the fixed steel groove 8. The mounting plates 9 are used to fixedly install the raiseboring machine and the winch.

[0043] To provide support for the excavation of the diversion tunnel shaft, in this embodiment, preferably, the system includes the following usage method:

[0044] S1. Excavate the expansion opening 2: Excavate the expansion opening 2 outside the selected point of the shaft, and after excavating the expansion opening 2, then open the diameter opening of the excavated shaft.

[0045] S2. Fix and install the card-edge round frame 3: After excavating the diameter hole, then fit the card-edge round frame 3 to the inner wall of the shaft tunnel 1 and the upper part of the expansion port 2, and then fix and install both sides through the first countersunk drill rod 4;

[0046] S3. Pour the first reinforced concrete layer 6 and lay the gravel layer 7: After the card-edge round frame 3 is installed and fixed, then pour the first reinforced concrete layer 6 at the edge of the expansion port 2, and then lay the gravel layer 7 on the first reinforced concrete layer 6 and the ground end;

[0047] S4. Lay and fix the steel trough 8 on the upper part of the gravel layer 7: Fix and lay the steel trough 8 on the gravel layer 7, and then fix and install it through the second countersunk drill rod 17, and a number of horizontal or vertical mounting plates 9 are welded on the steel trough 8, and the raise boring machine and the winch are fixed and installed through the mounting plates 9;

[0048] S5. Operate through the raise boring machine and the winch: Fix and install the raise boring machine on the mounting plate 9 to realize reverse pilot shaft construction. After the reverse pilot shaft construction is completed, remove the raise boring machine, and then install the winch to realize the hoisting of the hoisting tool, so that the workers use the leg-mounted pneumatic drill for construction operation.

[0049] In order to realize the excavation operation of the shaft tunnel 1, carry out support, and realize the pouring treatment of the shaft tunnel 1. In this embodiment, preferably, during the construction process of the leg-mounted pneumatic drill, a number of clamping circular grooves 10 are provided on the inner wall of the excavated shaft tunnel 1 for pouring and installation connection, and the wooden square frame 15 is installed first to prevent collapse and protect safety, and then the wooden square frame 15 is removed, and the second reinforced concrete layer 11, the waterproof layer 12 and the third reinforced concrete layer 13 are sprayed on the inner wall of the shaft tunnel 1 to form the complete shaft tunnel 1.

[0050] The working principle and usage process of the present invention:

[0051] The first step: Excavate the expansion port 2: Excavate the expansion port 2 outside the selected point of the shaft, and after excavating the expansion port 2, then excavate the diameter hole of the shaft tunnel;

[0052] The second step: Fix and install the card-edge round frame 3: After excavating the diameter hole, then fit the card-edge round frame 3 to the inner wall of the shaft tunnel 1 and the upper part of the expansion port 2, and then fix and install both sides through the first countersunk drill rod 4;

[0053] Step 3: Pour the first reinforced concrete layer 6 and lay the gravel layer 7: After the clamping edge circular frame 3 is installed and fixed, then pour the first reinforced concrete layer 6 at the edge of the expansion port 2, and then lay the gravel layer 7 on the first reinforced concrete layer 6 and the ground end;

[0054] Step 4: Lay and fix the steel trough 8 on the upper part of the gravel layer 7: Fix and lay the steel trough 8 on the gravel layer 7, and then fix and install it through the second countersunk drill rod 17. A number of horizontal or vertical mounting plates 9 are welded on the steel trough 8, and the raise boring machine and the hoist are fixedly installed through the mounting plates 9;

[0055] Step 5: Operate through the raise boring machine and the hoist: Fix and install the raise boring machine on the mounting plate 9 to realize the reverse pilot shaft construction. After the reverse pilot shaft construction is completed, remove the raise boring machine, and then install the hoist to realize the hoisting of the hoisting tool, so that the workers use the leg-type pneumatic drill for construction operations;

[0056] Step 6: Excavate and pour the shaft 1: During the construction process of the leg-type pneumatic drill, a number of clamping circular grooves 10 are formed on the inner wall of the shaft 1 that is cut out for pouring and installation connection. The wooden square frame 15 is installed first to prevent cave-ins and protect safety. Then, the wooden square frame 15 is removed, and the second reinforced concrete layer 11, the waterproof layer 12, and the third reinforced concrete layer 13 are sprayed on the inner wall of the shaft 1 to form the complete shaft 1.

[0057] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A diversion tunnel shaft excavation and support system, comprising a shaft tunnel (1), characterized in that: An expansion port (2) is provided at the ground end of the shaft (1). A clamping-edge circular frame (3) is fixedly installed on the expansion port (2). A support plate (5) is welded to one side of the clamping-edge circular frame (3). A first reinforced concrete layer (6) is cast on one side of the support plate (5). A number of fixed steel grooves (8) are fixedly installed on the ground end. A number of mounting plates (9) are welded to the fixed steel grooves (8); A second reinforced concrete layer (11) for spraying is provided inside the upper end of the shaft (1). A waterproof layer (12) is provided inside the second reinforced concrete layer (11). A third reinforced concrete layer (13) for spraying is provided inside the waterproof layer (12); A clamping circular ring groove (10) is provided inside the lower end of the shaft (1). A fixed frame (14) is inlaid and installed inside the clamping circular ring groove (10). A wooden square frame (15) is fixedly connected to the inside of the fixed frame (14); The clamping-edge circular frame (3) is arranged in an L-shaped arc. The upper side plate of the clamping-edge circular frame (3) is clamped and connected to the upper side of the expansion port (2). The lower side plate of the clamping-edge circular frame (3) is clamped and connected to the inner wall of the shaft (1). The two side plates of the clamping-edge circular frame (3) are fixedly installed through a number of first countersunk drill rods (4); A gravel layer (7) is laid on the first reinforced concrete layer (6) and the ground end. A number of the fixed steel grooves (8) are provided on the upper surface of the gravel layer (7). A number of the fixed steel grooves (8) are connected through second countersunk drill rods (17). The inner second countersunk drill rods (17) sequentially penetrate and connect in the gravel layer (7), the first reinforced concrete layer (6) and the soil layer. The outer second countersunk drill rods (17) sequentially penetrate and connect in the gravel layer (7) and the soil layer; The fixed frame (14) is in an arc shape. At least four of the fixed frames (14) are inlaid and installed inside the clamping circular ring groove (10). A number of the fixed frames (14) are fixedly connected through connecting bolts (16). A wooden square frame (15) is installed on the bottom inner wall of the shaft (1). The wooden square frame (15) is fixedly connected to the fixed frame (14) through the connecting bolts (16). A number of square holes are provided on the wooden square frame (15).

2. The diversion tunnel shaft excavation and support system according to claim 1, wherein: A number of clamping circular ring grooves (10) are provided on the entire shaft wall of the shaft (1). The second reinforced concrete layer (11) is also cast on the clamping circular ring groove (10) of the upper end of the shaft (1). The clamping circular ring grooves (10) are arranged circumferentially and vertically. The clamping circular ring grooves (10) are arranged circumferentially in four; 3. The diversion tunnel shaft excavation and support system according to claim 1, characterized in that: It further includes a control module, on which a power supply module for power supply operation is electrically connected, a data module is electrically connected to the control module, a pressure sensor is electrically connected to the data module, a comparison module is electrically connected to the data module, the comparison module is electrically connected to the control module, a drive module is electrically connected to the control module, an alarm module is electrically connected to the drive module, and the pressure sensor is installed inside the wooden square frame (15) and the card-edge circular frame (3).

4. A diversion tunnel shaft excavation and support system according to claim 1, characterized in that: A support ring plate (18) is fixedly inlaid in the middle of the shaft tunnel (1), and the support ring plate (18) is located below the second reinforced concrete layer (11), the waterproof layer (12) and the third reinforced concrete layer (13), and the support ring plate (18) is arranged in a semi-circular arc shape.

5. A diversion tunnel shaft excavation and support system according to claim 1, characterized in that: A plurality of horizontal or vertical mounting plates (9) are welded on the fixed steel groove (8), and the mounting plates (9) are used for fixedly installing the raise boring machine and the hoist.

6. A method for using a diversion tunnel shaft excavation and support system according to any one of claims 1-5, characterized in that: It includes the following steps S1. Excavate the expansion opening (2): Excavate the expansion opening (2) outside the selected point of the shaft, and after excavating the expansion opening (2), then excavate the diameter opening of the shaft tunnel. S2. Fix and install the card-edge circular frame (3): After excavating the diameter opening, then fit the card-edge circular frame (3) on the inner wall of the shaft tunnel (1) and the upper part of the expansion opening (2), and then fix it on both sides through the first countersunk drill rod (4). S3. Pour the first reinforced concrete layer (6) and lay the gravel layer (7): After the card-edge circular frame (3) is installed and fixed, then pour the first reinforced concrete layer (6) at the edge of the expansion opening (2), and then lay the gravel layer (7) on the first reinforced concrete layer (6) and the ground end. S4. Lay the fixed steel groove (8) on the upper part of the gravel layer (7): Fix and lay the fixed steel groove (8) on the gravel layer (7), and then fix it through the second countersunk drill rod (17), and a plurality of horizontal or vertical mounting plates (9) are welded on the fixed steel groove (8), and the raise boring machine and the hoist are fixedly installed through the mounting plates (9). S5. Operate through the raise boring machine and the hoist: Fix and install the raise boring machine on the mounting plate (9) to realize the reverse pilot shaft construction. After the reverse pilot shaft construction is completed, remove the raise boring machine, and then install the hoist to realize the hoisting of the hoisting tool, so that the workers use the leg-mounted pneumatic drill for construction operation.

7. The method of using a diversion tunnel shaft excavation and support system according to claim 6, characterized in that: During the construction process of the leg-mounted pneumatic drill, a plurality of clamping circular grooves (10) are opened on the inner wall of the excavated shaft tunnel (1) for pouring and installation connection. The wooden square frame (15) is installed first to prevent collapse and protect safety, and then the wooden square frame (15) is removed. The second reinforced concrete layer (11), the waterproof layer (12) and the third reinforced concrete layer (13) are sprayed on the inner wall of the shaft tunnel (1) to form the complete shaft tunnel (1).

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