Shield belt pressure entry construction method and supporting equipment

Abstract

The present invention relates to the field of soil or rock excavation technology and equipment, and in particular to a shield-driven pressure-entry construction method and supporting equipment. The shield-driven pressure-entry construction method is to set a partition device in the excavated tunnel behind the main body of the shield machine, and to form a closed air chamber in front of the partition device. After the construction personnel establish air pressure in the closed air chamber, they enter the closed air chamber under pressure to carry out construction. The present invention proposes for the first time a method of setting a partition device in the excavated tunnel behind the main body of the shield machine, and using a part of the tunnel as a closed air chamber. Air pressure can be established in the closed air chamber, so that at least the main body of the shield machine is located in a pressurized environment as a whole, thereby eliminating the need to rely on the shield body of the shield machine to specially establish a pressurized environment in the soil bin. Compared with the traditional pressurized construction method of building a pressurized environment inside the shield body of the shield machine, the present invention completely eliminates the influence of the shield diameter on the pressurized construction conditions, and solves the problem that small-diameter shield machines cannot enter the bin under pressure for construction.

Description

Technical Field

[0001] The present invention relates to the field of soil or rock stratum excavation technology and equipment, and in particular to a shield belt pressure entry construction method and a supporting device. Background Art

[0002] Tunnel excavation has gradually expanded beyond conventional subway systems to include water diversion, sewage disposal, and cable lines. In the construction of small-diameter municipal tunnels, such as those for sewage and cable lines, the excavation diameter is relatively small, ranging from 2-3.5 meters. When using a shield machine (TBM), the excavation diameter is typically between 2.5-4 meters. During tunnel excavation of these diameters, if foreign objects appear in the stratum or a cutter change is required, the shield machine's soil chamber must be pressurized to maintain face stability. Construction workers then enter the chamber under pressure. Because the pressure inside the chamber must be above atmospheric pressure before entering, a manhole is installed behind the shield machine's main drive. A sealed inner door is installed between the manhole and the soil chamber. When entering the chamber, construction workers first keep the inner door closed to maintain a high pressure inside the chamber. They then enter the chamber through the outer door at the rear of the manhole, close the outer door, and open the inner door to enter the chamber and perform the necessary operations.

[0003] However, when the shield excavation diameter is small, the existing design cannot meet the requirements of the man cabin arrangement due to the relatively compact internal space of the shield machine. To solve this problem, a patent application with publication number CN111852494A and publication date of October 30, 2020 provides an earth pressure balance shield machine. This earth pressure balance shield machine meets the international standard requirements for an independent man cabin by providing an independent man cabin, but it leads to an increase in the length of the shield machine main body, which weakens its turning ability and increases the design cost. Moreover, even if this structure is adopted, it is only barely feasible when the shield excavation diameter reaches 4m or more, and the shield machine shell needs to be specially lengthened, resulting in an increase in the length of the shield machine main body. On the one hand, this will further weaken the shield machine's own turning ability and cannot meet the requirements of small curve construction (most small-diameter tunnels are located in urban areas, and the tunnel curve is generally very small to avoid buildings, etc.); on the other hand, the lengthening of the main body shell will sharply increase the cost of the shield machine itself.

[0004] Furthermore, for shield machines with smaller diameters, even with the aforementioned structure, the layout of an independent man cabin within the shield machine is not sufficient. Furthermore, when the diameter of the shield machine is small, the internal space of the soil bunker is very small. During pressurized entry operations, at least two workers are required to enter the bunker. Once personnel enter the bunker, the volume of pressurized air contained within the already extremely small bunker decreases dramatically, which can easily lead to instability in the tunnel face. To stabilize the tunnel face, the compressed air pressure within the bunker must be increased, forcing construction workers to work in a higher-pressure environment, increasing the risk to the workers. Furthermore, as the effective compressed air volume within the bunker decreases, as workers work, the oxygen concentration within the bunker becomes too low as oxygen is consumed, causing hypoxia. Summary of the Invention

[0005] The present invention aims to provide a method for shield tunneling with pressure to solve the problem that small-diameter shield machines cannot be used for pressure tunneling. At the same time, the present invention also aims to provide a supporting device for shield tunneling with pressure to implement the above method.

[0006] In order to solve the above problems, the shield tunneling pressure-entering construction method of the present invention adopts the following technical solutions: the shield tunneling pressure-entering construction method is to set a partition device in the excavated tunnel behind the shield machine main body and behind the rear supporting trailer, and form a closed air chamber in front of the partition device. After the construction personnel establish air pressure in the closed air chamber, they enter the closed air chamber under pressure to carry out construction.

[0007] Beneficial effects: The present invention proposes for the first time a method of setting up a partition device in the excavated tunnel behind the shield machine main body, using a part of the tunnel as a closed air chamber, which can establish air pressure in the closed air chamber, so that at least the shield machine main body as a whole is located in a pressurized environment, thereby eliminating the need to rely on the shield body of the shield machine to specifically establish a pressurized environment in the soil bin. Compared with the traditional pressurized construction method of building a pressurized environment inside the shield body of the shield machine, the invention completely eliminates the influence of the shield diameter on the pressurized construction conditions, and solves the problem that small-diameter shield machines cannot enter the bin for pressurized construction.

[0008] Furthermore, the partition device includes a cylindrical base and a partition disposed within the cylindrical base. Grouting is performed between the cylindrical base and the tunnel wall to achieve a seal between the partition device and the tunnel wall. Grouting between the cylindrical base and the tunnel wall ensures a reliable seal between the cylindrical base and the tunnel wall, while also improving the bonding strength between the two and enhancing the pressure resistance of the partition device.

[0009] Furthermore, before installing the partition device, the pipes, air ducts, and cables at the corresponding location are disconnected, and the track at the location is removed. After disconnecting the pipes, air ducts, and cables at the corresponding location and removing the track, the difficulty of laying out the partition device is greatly reduced, and the corresponding avoidance and sealing structures are no longer required on the partition device, simplifying the structure of the partition device itself.

[0010] Furthermore, by configuring the partition device with an independent man cabin, construction workers can enter the closed air chamber under pressure. The independent man cabin can help simplify the structure of the partition device and speed up its installation efficiency.

[0011] The shield belt pressure entry construction supporting device of the present invention adopts the following technical scheme: the shield belt pressure entry construction supporting device includes a partition device, the partition device includes a cylindrical base and a partition used to be arranged in the cylindrical base, the outer diameter of the cylindrical base is not larger than the inner diameter of the tunnel to be isolated, the outer side surface of the cylindrical base is used to seal with the inner wall surface of the tunnel to be isolated, the partition and the cylindrical base are sealed or are an integrated structure, and the partition is provided with a through-canister joint for the auxiliary pipelines required for construction to pass through and a personnel entrance and exit.

[0012] Beneficial effect: By adopting the supporting device of the present invention, a closed air chamber can be separated in the tunnel through the partition device, and auxiliary channels such as water and gas cables can be established between the closed air chamber and the outside world through the through-chamber joint, thereby providing support for the implementation of the method of the present invention.

[0013] Furthermore, the supporting device also includes an independent cabin, which can help simplify the structure of the partition device and speed up its installation efficiency.

[0014] Furthermore, radially outwardly projecting flanges are provided at each end of the cylindrical base. These flanges are used to enclose a grouting chamber between the tunnel wall and the outer wall of the cylindrical base. Grouting holes are provided on the cylindrical base, communicating with the grouting chamber. With these grouting chambers and grouting holes, grouting can be performed between the cylindrical base and the tunnel wall. This not only ensures a reliable seal between the cylindrical base and the tunnel wall, but also enhances the bonding strength between the two, improving the pressure resistance of the partition device.

[0015] Furthermore, the cylindrical base is constructed from three or more curved panels, with the adjacent sides of two adjacent curved panels freely disposed relative to each other. The remaining adjacent curved panels are hingedly connected and internally connected to a telescopic control rod, which controls the expansion and folding of the corresponding two curved panels. The cylindrical base is constructed from three or more curved panels, and the configuration of the telescopic control rod allows for rapid folding and unfolding of the cylindrical base, facilitating both transportation and installation.

[0016] Furthermore, the partition is formed by splicing two or more plates, and the inner wall of the cylindrical base is provided with a slot for the partition to be snapped into. The partition is formed by splicing two or more plates, and the inner wall of the cylindrical base is provided with a slot for the partition to be snapped into. When installing the partition, it can be installed piece by piece, thereby reducing its installation strength.

[0017] Furthermore, connecting edges extending to one side are provided between adjacent plates. The connecting edges connect the adjacent plates, so that after the partitions are snapped into the slots on the cylindrical base one by one, they are connected to form an integral structure and automatically retained in the slots, enabling rapid assembly. Furthermore, the connecting edges facilitate sealing, ensuring the sealing performance of the plate connections, thereby ensuring the airtightness of the enclosed air chamber separated within the tunnel. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of embodiment 1 of the shield belt pressure entry construction method of the present invention; it is also a schematic diagram of the use state of embodiment 1 of the shield belt pressure entry construction supporting device of the present invention;

[0019] Figure 2 yes Figure 1 A local enlarged view at position I;

[0020] Figure 3 This is a structural diagram of the cylindrical base in Example 1 of the shield belt pressing chamber construction supporting device of the present invention (in hoisting state);

[0021] Figure 4 This is a schematic structural diagram of the cylindrical base in Example 1 of the shield belt pressure chamber construction supporting device of the present invention (installed and expanded state);

[0022] Figure 5 This is a schematic structural diagram of the cylindrical base in Example 1 of the shield belt pressure chamber construction supporting device of the present invention (installation completed state);

[0023] Figure 6 This is a schematic structural diagram of the partition in Example 1 of the shield belt pressure chamber construction supporting device of the present invention;

[0024] Figure 7 yes Figure 6 A cross-sectional view of the partition in FIG.

[0025] In the figure: 101, partition device; 102, man cabin; 11, cylindrical base; 111, grouting hole; 112, first curved plate; 113, second curved plate; 114, L-shaped hinge seat; 115, hinged ear plate; 116, lifting ring; 117, telescopic control rod; 12, partition; 121, center hole; 122, first plate; 123, second plate; 124, third plate; 125, sealing element; 126, through-chamber joint; 127, guide ring; 104, transport trolley; 105, shield machine main unit; 106, closed air chamber; 107, rear supporting trailer; 108, T-block. DETAILED DESCRIPTION

[0026] In order to make the objectives, technical solutions, and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present invention and are not intended to limit the present invention. That is, the embodiments described herein are only some embodiments of the present invention, not all embodiments. Generally, the components of the embodiments of the present invention described and illustrated in the drawings herein may be arranged and designed in various different configurations.

[0027] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but is merely intended to represent selected embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative work are within the scope of protection of the present invention.

[0028] It should be noted that relational terms such as "first" and "second" that may appear are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, terms such as "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article or device. In the absence of further limitations, an element defined by a sentence such as "including a..." does not exclude the presence of other identical elements in the process, method, article or device that includes the element.

[0029] The features and performance of the present invention are further described in detail below with reference to the embodiments.

[0030] Example 1 of the shield belt pressure entering warehouse construction supporting device of the present invention:

[0031] like Figure 1-7As shown, the shield belt pressure entry construction supporting device includes a partition device 101 and a man cabin 102.

[0032] The partition device 101 includes a cylindrical base 11 and a partition plate 12 provided on the cylindrical base 11 .

[0033] The structure of the cylindrical base 11 is as follows Figure 3-5 As shown, the outer diameter of the cylindrical base 11 is smaller than the inner diameter of the tunnel to be separated. When it is installed on the tunnel wall of the corresponding tunnel, a grouting chamber (such as Figure 1 、 2 The cylindrical base 11 has grouting holes 111 pre-set on its wall. During use, grouting can be injected into the grouting chamber through the grouting holes 111. After the grouting solidifies, a seal can be achieved between the cylindrical base 11 and the tunnel wall. An annular groove is provided on the inner wall of the cylindrical base 11, which can be used to clamp the partition 12.

[0034] In this embodiment, the cylindrical base 11 is composed of three arc-shaped plates, among which the cross-section of the arc-shaped plate located at the bottom when in use is semicircular, which is referred to as the first arc-shaped plate 112 here, and the arc-shaped surfaces of the other two arc-shaped plates each form a 1 / 4 circle, which are referred to as the second arc-shaped plate 113 here. L-shaped hinges 114 are provided on the inner walls of the first curved plate 112 adjacent to the two second curved plates 113. A hinged lug 115 corresponding to the L-shaped hinge 114 is provided on one side of the second curved plates 113 adjacent to the first curved plate 112, while the other side is not constrained. The L-shaped hinge 114 cooperates with the hinged lug 115 to hinge the first curved plate 112 and the second curved plate 113 together. This allows the cylindrical base 11 to be folded during transportation and hoisting, and unfolded during use. Furthermore, due to the L-shaped hinge 114, a sealing gasket can be sandwiched between the first curved plate 112 and the second curved plate 113 during use to achieve a seal at the connection between the two. Lifting rings 116 are provided on the outer surfaces of the two second curved plates 113 near the L-shaped hinge 114 for use in hoisting and lifting the cylindrical base 11.

[0035] In order to achieve rapid folding and unfolding of the cylindrical base 11, in the present embodiment, a telescopic control rod 117 is further provided between the first curved plate 112 and the second curved plate 113 of the cylindrical base 11. The telescopic control rod 117 here is specifically a hydraulic jack (other embodiments may also be screw jacks, cylinders, etc.). Through the extension and contraction of the telescopic control rod 117, the cylindrical base 11 can be rapidly folded and unfolded. The telescopic control rod 117 is connected to the first and second curved plates through hinged ear plates provided on the inner wall surfaces of the first and second curved plates. It should be noted here that, in the present embodiment, in order to facilitate the installation of the partition 12, the L-shaped hinge seat 114, the hinged ear plate cooperating with the L-shaped hinge seat 114, and the hinged ear plate cooperating with the telescopic control rod 117 are all detachable structures. After the cylindrical base 11 is positioned during the installation process, all of the above components can be removed (such as Figure 5 ).

[0036] The structure of the partition 12 is as follows Figure 6 、 7 As shown, it is annular, with a central hole 121 formed in the center for construction workers to pass through, i.e., the personnel entrance and exit. In this embodiment, the partition 12 is made of four plates spliced ​​together, which is a split structure. Figure 6 The lowest plate is called the first plate 122, the highest plate is called the second plate 123, and the remaining two plates are called the third plates 124. The first plate 122 is semi-circular, the second plate 123 is an isosceles trapezoid, and the third plate 124 is arc-shaped. Adjacent edges of each plate are provided with connecting edges extending toward one side (in this embodiment, the outer side, i.e., the side away from the shield machine main body). Bolt holes are provided in the connecting edges. During installation, the first plate 122 is first installed into the annular groove provided on the inner wall of the cylindrical base 11. Then, the two third plates 124 are installed in sequence. Finally, the second plate 123 is inserted from bottom to top into the blank space left between the two third plates 124. This completes the installation of the partition 12. The plates of the partition 12 are fastened together by bolts along the adjacent connecting edges to form a whole. To ensure the sealing of the joints, seals 125 are provided between the connecting edges of each plate and between the partition and the cylindrical base. To provide the shield machine with the auxiliary air, water, and cables required for construction, a through-chamber connector 126 is installed on the partition. Ball valves are installed on the auxiliary air and water connectors to enable on / off switching. Cable connectors can be made of wall bushings commonly used in electrical cabinets, and their details are omitted here.

[0037] In this embodiment, the cabin 102 is an independent cabin. When in use, it can be transported to the rear side of the partition 12 by a transport trolley 104 and docked with the partition 12. To ensure positioning between the cabin 102 and the partition 12, a guide ring 127 is provided on the rear side of the partition 12. In this embodiment, the guide ring 127 is also formed by splicing arc-shaped plates provided on each plate of the partition 12.

[0038] Example 2 of the shield belt pressure-entry construction supporting device of the present invention:

[0039] In Example 1 of the shield belt pressing chamber construction supporting device of the present invention, the cylindrical base is cylindrical as a whole. In this embodiment, the cylindrical base includes a cylinder and flanges at both ends of the cylinder that protrude radially outward. The flanges can better form a grouting chamber between the walls of the tunnel.

[0040] Example 3 of the shield belt pressure entering warehouse construction supporting device of the present invention:

[0041] In Examples 1 and 2 of the shield tunneling belt-pressing chamber construction supporting device of the present invention, the cylindrical base comprises three curved plates. In this embodiment, there are four curved plates, with the adjacent sides of two adjacent curved plates freely disposed relative to each other. The remaining adjacent curved plates are hingedly connected and internally connected to telescopic control rods. This embodiment enables the cylindrical base to be folded to a smaller size. Of course, in other embodiments, the number of curved plates can be increased.

[0042] Example 4 of the shield belt pressure chamber construction supporting device of the present invention:

[0043] In Examples 1-3 of the shield tunneling belt-pressed entry construction device of the present invention, some of the curved plates of the cylindrical base are hingedly connected. In this embodiment, the curved plates are not connected to each other when not installed. During installation, they are bolted together using connections at their edges or directly welded. Of course, in other embodiments, when the shield diameter is smaller, a cylindrical base with an integrated structure can also be used.

[0044] Example 5 of the shield belt pressure-entry construction supporting device of the present invention:

[0045] In embodiments 1-4 of the shield belt pressure chamber construction supporting device of the present invention, a split structure is adopted between the cylindrical base and the partition. In this embodiment, the partition and the cylindrical base are configured as one body.

[0046] Example 6 of the shield belt pressure-entry construction supporting device of the present invention:

[0047] In Examples 1-4 of the shield tunneling belt pressure chamber construction supporting device of the present invention, the partitions adopted a split-piece spliced ​​structure. In this embodiment, the body adopts a single-piece structure. Of course, when the partitions adopt a split-piece spliced ​​structure, the plates can also be welded to each other or to the cylindrical base.

[0048] Example 7 of the shield belt pressure chamber construction supporting device of the present invention:

[0049] In the embodiments 1-6 of the shield belt pressure chamber construction supporting device of the present invention, the man cabin is an independent man cabin. In the present embodiment, the man cabin is integrated into the partition device.

[0050] Example 1 of the shield belt pressure entering warehouse construction method of the present invention:

[0051] This method can be implemented with the assistance of the shield belt pressure entry construction supporting device of the present invention. In this embodiment, the shield belt pressure entry construction supporting device specifically adopts the structure of Example 1 of the shield belt pressure entry construction supporting device of the present invention.

[0052] like Figure 1 、 2 As shown, the method is to install a partition device 101 in the excavated tunnel behind the shield machine main body 105, and form a closed air chamber 106 in front of the partition device 101. After the construction personnel build up air pressure in the closed air chamber 106, they enter the closed air chamber 106 under pressure to carry out construction. In this embodiment, the partition device 101 is installed behind the rear supporting trailer 107 of the shield machine main body. Before installing the partition device 101, the pipelines, air ducts and cables at the corresponding positions are first disconnected, and the tracks at the positions are removed. When entering the closed air chamber 106, the construction personnel enter through the man cabin 102, which is transported to the rear side of the partition by a transport cart. When installing the partition device's cylindrical base 11, T-shaped blocks 108 are first installed within the tunnel wall segments. These blocks are inserted into the grooves between the segments, providing a good positioning effect. The cylindrical base is pre-fixed by welding the T-shaped blocks to the base, and then finally secured by grouting. The partition device 101 can be dismantled after a single pressurized bunker installation and reused.

[0053] Example 2 of the shield belt pressure-entering construction method of the present invention:

[0054] In Example 1 of the shield belt pressure entry construction method of the present invention, the partition device used is the partition device in the shield belt pressure entry construction supporting device of the present invention. In this embodiment, the partition device is a partition wall formed in the tunnel by civil engineering.

Claims

1. The shield belt pressure entering warehouse construction method is characterized by: The method is to set a partition device in the excavated tunnel behind the main shield machine and behind the rear supporting trailer, and form a closed air chamber in front of the partition device. After the construction personnel build up air pressure in the closed air chamber, they enter the closed air chamber under pressure to carry out construction; the partition device includes a cylindrical base and a partition, and the partition is connected to an independent man cabin for construction personnel to enter and exit the closed air chamber. Grouting holes are preset on the wall of the cylindrical base, and the sealing cooperation between the partition device and the tunnel wall is achieved by grouting between the cylindrical base and the tunnel wall; the cylindrical base is spliced ​​by three arc plates, and the adjacent sides of the two upper arc plates are freely arranged relative to each other, and the lower arc plate is hingedly connected to the two upper arc plates through an L-shaped hinge seat and a hinged ear plate arranged on the inner wall of the arc plate, and a telescopic control rod is connected through the hinged ear plate separately arranged on the inner wall of the arc plate. The L-shaped hinge seat, the hinged ear plate that cooperates with the L-shaped hinge seat, and the hinged ear plate that cooperates with the telescopic control rod are all detachable structures, so that they can all be removed after the positioning of the cylindrical base is completed; an annular groove for clamping the partition is provided on the inner wall of the cylindrical base, and the partition is made up of four plates. The plate at the bottom is semi-circular, the plate at the top is an isosceles trapezoid, and the remaining two plates are arc-shaped. The adjacent edges of each plate are provided with a connecting edge extending to one side. During installation, the bottom plate is first installed into the annular groove provided on the inner wall of the cylindrical base, and then the two arc-shaped plates are installed in turn, and finally the top plate is inserted from bottom to top into the blank area left between the two arc-shaped plates. After each plate is clamped into the annular groove one by one, it is fastened by bolts along the adjacent connecting edges to form a whole and automatically remain in the annular groove. It is removed after the single pressure-entry construction is completed.

2. The shield belt pressure entering warehouse construction method according to claim 1 is characterized in that: Before setting up the partition device, first disconnect the pipelines, air ducts and cables at the corresponding positions and remove the tracks at the positions.

3. The shield belt pressure entering the chamber construction supporting device is characterized by: The invention comprises a partition device, wherein the partition device comprises a cylindrical base and a partition plate for being arranged in the cylindrical base, the outer diameter of the cylindrical base is not larger than the inner diameter of the tunnel to be partitioned, the outer side surface of the cylindrical base is used to seal with the inner wall surface of the tunnel to be partitioned, the partition plate is sealed with the cylindrical base, and a through-bin joint and a personnel entrance and exit for auxiliary pipelines required for construction are provided on the partition plate, and an independent man cabin for construction personnel to enter and exit the closed air chamber is docked with the partition plate, and a grouting hole is preset on the wall of the cylindrical base, and the sealing between the partition device and the tunnel wall is achieved by grouting between the cylindrical base and the tunnel wall; the cylindrical base is spliced ​​by three arc-shaped plates, the adjacent sides of the two upper arc-shaped plates are freely arranged relative to each other, the lower arc-shaped plate and the two upper arc-shaped plates are hingedly connected to each other by an L-shaped hinge seat and a hinged ear plate arranged on the inner wall of the arc-shaped plate and are respectively arranged on the inner wall of the arc-shaped plate The hinged ear plate is connected to the telescopic control rod, and the L-shaped hinge seat, the hinged ear plate cooperating with the L-shaped hinge seat, and the hinged ear plate cooperating with the telescopic control rod are all detachable structures, so that they can all be removed after the positioning of the cylindrical base is completed; an annular groove for clamping the partition is provided on the inner wall of the cylindrical base, and the partition is composed of four plates, the plate located at the bottom is semi-circular, the plate located at the top is an isosceles trapezoid, and the remaining two plates are arc-shaped, and the adjacent edges of each plate are provided with a connecting edge extending toward one side. During installation, the bottom plate is first installed into the annular groove provided on the inner wall of the cylindrical base, and then the two arc plates are installed in sequence, and finally the top plate is inserted from bottom to top into the blank area left between the two arc plates. After each plate is clamped into the annular groove one by one, it is fastened by bolts along the adjacent connecting edges to form a whole and automatically remain in the annular groove. It is removed after the single pressure-entry construction is completed.

4. The shield belt pressure entering chamber construction supporting device according to claim 3 is characterized in that: Both ends of the cylindrical base are respectively provided with flanges protruding radially outward, and the flanges are used to enclose a grouting chamber between the tunnel wall and the outer wall of the cylindrical base, and the grouting hole is communicated with the grouting chamber.

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