Shield tunnel reinforcing device

Abstract

The utility model discloses a shield tunnel reinforcing device which comprises a shield tunnel, a cushion layer is arranged on the outer side of the shield tunnel, grouting holes communicated with the cushion layer are formed in the inner wall of the shield tunnel, cement-soil piles extending in the radius direction of the shield tunnel are arranged on the outer side of the cushion layer, and the cement-soil piles and the cushion layer are connected into a whole. According to the scheme, the reinforcing depth is large, the construction difficulty of treating the underlying deep soft soil of the shield tunnel is reduced, the grouting construction disturbance is small, and the reinforcing quality is controllable by clinging to the shield tunnel; and the mattress layer is additionally arranged, so that a plurality of cement-soil piles can be connected, and the overall quality and the sinking control effect of the cement-soil piles of the shield tunnel can be effectively improved.

Description

Technical Field

[0001] The utility model relates to the technical field of shield tunnels, in particular to a shield tunnel reinforcement device. Background Art

[0002] Soft soils with high sensitivity, low shear strength, high moisture content, and high compressibility are widely distributed along my country's rivers and coasts. Shield tunnels in these soft soils face major challenges, including failure of bearing capacity, long-term settlement, differential settlement, structural damage, waterproofing failure, and reduced durability. Therefore, early settlement control measures are necessary for shield tunnels.

[0003] Currently, there are few methods for treating shield tunnel settlement problems. Ground reinforcement is typically performed on the sides or below the underlying tunnel. Ground reinforcement is limited by ground conditions, and the reinforcement cannot be placed close to the tunnel structure. Construction methods such as channel-cut cement-soil diaphragm walls (TRDs), triaxial cement mixing piles, and high-pressure jet grouting piles are extremely difficult in areas with dense pipelines or above-ground structures. Furthermore, full-section grouting, used to strengthen the ground between the ground and the tunnel bottom, is labor-intensive and inefficient.

[0004] For example, Chinese patent publication number CN108005682A, published on May 28, 2018, is titled "A method for reinforcing a shield tunnel" and includes the following steps: forming a mixing pile on the outside of the shield tunnel; setting a grouting hole between the mixing pile and the shield tunnel, installing a sleeve valve pipe in the grouting hole, and installing a one-way valve on the upper end of the sleeve valve pipe; sealing the gap formed between the grouting hole and the outer wall of the sleeve valve pipe with quick-setting cement mortar; grouting is performed in the grouting hole, and the grouting effect is inspected after the grouting is completed, and supplementary grouting is performed for unqualified sections.

[0005] The disadvantages of existing patents are: existing shield tunnels usually reinforce the soil on the sides or below the underlying tunnel on the ground. The ground reinforcement is limited by ground conditions, the reinforcement body cannot be close to the tunnel structure, and the construction is extremely difficult, and the quality of the reinforcement body is uncontrollable. Utility Model Content

[0006] The purpose of the utility model is to solve the problem that existing shield tunnels usually reinforce the soil on the sides or below the underlying tunnel on the ground, the ground reinforcement is limited by ground conditions, the reinforcement body cannot be close to the tunnel structure, resulting in construction difficulty and uncontrollable quality of the reinforcement body, and to provide a shield tunnel reinforcement device that reduces the construction difficulty and has controllable reinforcement body quality.

[0007] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0008] A shield tunnel reinforcement device includes a shield tunnel, a cushion layer is provided on the outside of the shield tunnel, grouting holes connected to the cushion layer are provided on the inner wall of the shield tunnel, and cement soil piles are provided on the outside of the cushion layer and extend along the radial direction of the shield tunnel, and the cement soil piles are connected to the cushion layer as a whole. The shield tunnel reinforcement device described in this solution adopts high-pressure grouting suction construction in the shield tunnel to form cement soil piles, and the cement soil piles extend outward along the radial direction of the shield tunnel. The cement soil piles solve the problem of insufficient reinforcement depth of the shield tunnel, and the cement soil piles can meet the construction requirements in deep soft soil layers. Cement soil piles are used to reinforce shield tunnels, and have the advantages of large reinforcement depth, reduced difficulty in handling the deep soft soil under the shield tunnel, small disturbance during grouting construction, and controllable reinforcement quality close to the shield tunnel. A cushion layer is provided on the outside of the shield tunnel. When the shield tunnel is used to support deep soft soil beneath the shield tunnel, the cement soil piles are located in the lower portion of the shield tunnel. Multiple cement soil piles are connected by the cushion layer, enhancing the overall strength of the shield tunnel reinforcement device. The addition of a cushion layer connects the multiple cement soil piles, effectively improving the overall quality and settlement control of the shield tunnel cement soil piles.

[0009] Preferably, a synchronous grouting layer is provided on the outer wall of the shield tunnel, the cushion layer is located on the outer wall of the synchronous grouting layer, and the synchronous grouting layer, the cushion layer, and the cement-soil piles are integrally connected. The shield tunnel is formed by a plurality of shield segments aligned together, the synchronous grouting layer is constructed simultaneously with the shield tunnel, and the cushion layer is located on the outer wall of the synchronous grouting layer. The synchronous grouting layer improves the connection strength between the cushion layer and the shield tunnel, further increasing the reinforcement strength of the shield tunnel's reinforcement device.

[0010] Preferably, the cement-soil piles include vertical cement-soil piles and diagonal cement-soil piles, each of which is integrally connected to the cushion layer. These vertical cement-soil piles and diagonal cement-soil piles significantly increase the reinforcement depth, reduce the difficulty of handling deep soft soil beneath the shield tunnel, minimize grouting disturbance, and uniformly reinforce the outer wall of the shield tunnel.

[0011] Preferably, the plurality of vertical cement-soil piles are arranged along the axis of the shield tunnel; the plurality of inclined cement-soil piles are arranged on either side of a common plane containing the central axes of the plurality of vertical cement-soil piles. The vertical cement-soil piles are arranged along the axis of the shield tunnel, thereby reducing the difficulty of handling deep soft soil beneath or above the shield tunnel and ensuring that the reinforcement force of the reinforcement device is evenly distributed along the axis of the shield tunnel.

[0012] Preferably, the oblique cement-soil piles are symmetrically arranged along the same plane where the central axes of the plurality of vertical cement-soil piles are located, so that the reinforcement force of the reinforcement device is evenly distributed along the circumference of the shield tunnel.

[0013] Preferably, the oblique cement-soil piles located on either side of the same plane where the central axes of the plurality of vertical cement-soil piles lie are arranged along the axis of the shield tunnel, so that the reinforcement force of the reinforcement device is evenly distributed along the axis and circumference of the shield tunnel.

[0014] Preferably, the oblique soil-cement piles on either side of the same plane as the central axis of the plurality of vertical soil-cement piles are arranged in a plum blossom pattern. This allows the reinforcement force of the reinforcement device to be evenly distributed along the axis and circumference of the shield tunnel, while reducing the number of soil-cement piles, thereby meeting reinforcement requirements while reducing reinforcement costs.

[0015] Preferably, the cross-section of the cushion layer is circular or semicircular. When only the difficulty of handling deep soft soil beneath the shield tunnel needs to be reduced, the cross-section of the cushion layer is semicircular and the cushion layer is located below the shield tunnel. When strict control of shield tunnel deformation is required, the cross-section of the cushion layer is circular.

[0016] Preferably, the cushion layer comprises multiple lower cushion layer units located below the outer sidewall of the shield tunnel. Each lower cushion layer unit is provided with a vertical cement-soil pile and inclined cement-soil piles symmetrically arranged on either side of the vertical cement-soil pile. There is at least one inclined cement-soil pile on either side of the vertical cement-soil pile. To minimize the difficulty of handling deep, soft soil beneath the shield tunnel, the upper cushion layer unit can have a semicircular cross-section to achieve deformation control.

[0017] Preferably, the cushion layer further comprises a plurality of upper cushion layer units located above the outer sidewall of the shield tunnel. The plurality of upper cushion layer units are arranged and connected along the axis of the shield tunnel. A vertical cement soil pile is disposed on the outer side of each upper cushion layer unit, and inclined cement soil piles are symmetrically arranged on either side of the vertical cement soil pile. There is at least one inclined cement soil pile on either side of the vertical cement soil pile. When strict deformation control is required for the shield tunnel, the cross-sections of the upper cushion layer units and the lower cushion layer units are aligned to form a circular ring, thereby enhancing deformation control.

[0018] Therefore, the present invention has the following beneficial effects: (1) the reinforcement depth is large, which reduces the construction difficulty of treating the deep soft soil under the shield tunnel, the grouting construction disturbance is small, and the reinforcement quality is controllable because it is close to the shield tunnel; (2) the addition of a cushion layer can realize the connection between multiple cement soil piles, which can effectively improve the overall quality and settlement control effect of the cement soil piles in the shield tunnel. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a structural diagram of the fourth embodiment of the present invention.

[0020] Figure 2 This is another structural diagram of the fourth embodiment of the present invention.

[0021] Figure 3 This is a structural diagram of the fifth embodiment of the present invention.

[0022] Figure 4 This is a structural diagram of the second embodiment of the present invention.

[0023] Figure 5 This is a structural diagram of the third embodiment of the present invention.

[0024] As shown in the picture:

[0025] Shield tunnel 1,

[0026] Mattress layer 2, synchronous grouting layer 3,

[0027] Vertical cement soil piles 4, inclined cement soil piles 5. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solutions and advantages of the embodiments of the technical solution of the present invention clearer, the present invention is further described below in conjunction with the accompanying drawings and specific implementation methods.

[0029] Example 1, as Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 、 Figure 5 A shield tunnel 1 reinforcement device shown includes a shield tunnel 1, a mattress layer 2 is provided on the outside of the shield tunnel 1, grouting holes connected to the mattress layer 2 are provided on the inner wall of the shield tunnel 1, and cement soil piles extending along the radial direction of the shield tunnel 1 are provided on the outside of the mattress layer 2, and the cement soil piles are connected to the mattress layer 2 as a whole.

[0030] In the above-described embodiment, a shield tunnel reinforcement device 1 employs high-pressure grouting and suction construction within the shield tunnel 1 to form cement-soil piles. The cement-soil piles extend outward along the radius of the shield tunnel 1. These cement-soil piles address the problem of insufficient reinforcement depth in the shield tunnel 1 and meet construction requirements within deep soft soil layers. Cement-soil piles reinforce the shield tunnel 1, offering advantages such as a large reinforcement depth, reduced difficulty in handling the deep soft soil beneath the shield tunnel 1, minimal grouting disturbance, and controllable reinforcement quality close to the shield tunnel 1. A cushion layer 2 is provided on the outer side of the shield tunnel 1. When the shield tunnel 1 is used to support deep soft soil beneath the shield tunnel 1, multiple cement-soil piles are located at the bottom of the shield tunnel 1. These multiple cement-soil piles are connected by the cushion layer 2, enhancing the overall strength of the shield tunnel reinforcement device 1. The addition of the cushion layer 2 allows for connection between the multiple cement-soil piles, effectively improving the overall quality and settlement control of the cement-soil piles in the shield tunnel 1. The invention solves the problem that the existing shield tunnel 1 usually reinforces the soil on the side or below the underlying tunnel on the ground, the ground reinforcement is limited by ground conditions, the reinforcement body cannot be close to the tunnel structure, the construction is extremely difficult, and the quality of the reinforcement body is uncontrollable.

[0031] In this embodiment, a synchronous grouting layer 3 is provided on the outer wall of the shield tunnel 1. The cushion layer 2 is located on the outer wall of the synchronous grouting layer 3. The synchronous grouting layer 3, the cushion layer 2, and the cement-soil piles are integrally connected. The shield tunnel 1 is formed by a plurality of shield segments. The synchronous grouting layer 3 is constructed simultaneously with the shield tunnel 1. The cushion layer 2 is located on the outer wall of the synchronous grouting layer 3. The synchronous grouting layer 3 improves the connection strength between the cushion layer 2 and the shield tunnel 1, further enhancing the reinforcement strength of the shield tunnel 1's reinforcement device.

[0032] Specifically, the cement-soil piles include vertical cement-soil piles 4 and diagonal cement-soil piles 5, each integrally connected to the cushion layer 2. These piles significantly increase the reinforcement depth, reduce the difficulty of handling the deep, soft soil beneath the shield tunnel 1, minimize grouting disturbances, and evenly reinforce the outer wall of the shield tunnel 1.

[0033] Furthermore, the cross-section of the cushion layer 2 is circular or semicircular. When it is only necessary to reduce the difficulty of handling the deep soft soil under the shield tunnel 1, the cross-section of the cushion layer 2 is semicircular and the cushion layer 2 is located at the bottom of the shield tunnel 1. When the deformation of the shield tunnel 1 is strictly controlled, the cross-section of the cushion layer 2 is circular.

[0034] In the second embodiment, the basic structure is further optimized on the basis of the first embodiment, such as Figure 4As shown, there are multiple vertical cement-soil piles 4 arranged along the axis of the shield tunnel 1. There are also multiple oblique cement-soil piles 5, each arranged on either side of the same plane as the central axis of the multiple vertical cement-soil piles 4. The arrangement of the vertical cement-soil piles 4 along the axis of the shield tunnel 1 reduces the difficulty of handling deep soft soil beneath or above the shield tunnel 1 and ensures that the reinforcement force of the reinforcement device is evenly distributed along the axis of the shield tunnel 1.

[0035] Further, such as Figure 4 As shown, the oblique cement soil piles 5 are symmetrically arranged along the same plane where the central axes of the plurality of vertical cement soil piles 4 are located, so that the reinforcement force of the reinforcement device is evenly distributed along the circumference of the shield tunnel 1 .

[0036] Further, such as Figure 4 As shown, the oblique cement-soil piles 5 located on either side of the same plane where the central axes of the plurality of vertical cement-soil piles 4 lie are arranged along the axis of the shield tunnel 1. This allows the reinforcement force of the reinforcement device to be evenly distributed along the axis and circumference of the shield tunnel 1.

[0037] In the third embodiment, the basic structure is further optimized on the basis of the first embodiment, such as Figure 5 As shown, there are multiple vertical cement-soil piles 4 arranged along the axis of the shield tunnel 1. There are also multiple oblique cement-soil piles 5, each arranged on either side of the same plane as the central axis of the multiple vertical cement-soil piles 4. The arrangement of the vertical cement-soil piles 4 along the axis of the shield tunnel 1 reduces the difficulty of handling deep soft soil beneath or above the shield tunnel 1 and ensures that the reinforcement force of the reinforcement device is evenly distributed along the axis of the shield tunnel 1.

[0038] Further, such as Figure 5 As shown, the oblique soil-cement piles 5, located on either side of the same plane as the central axes of the multiple vertical soil-cement piles 4, are arranged in a plum blossom pattern. This ensures that the reinforcement force of the reinforcement device is evenly distributed along the axis and circumference of the shield tunnel 1, while reducing the number of soil-cement piles, thereby meeting reinforcement requirements while reducing reinforcement costs.

[0039] Example 4, as Figure 1 、 Figure 2 As shown, a shield tunnel 1 reinforcement device includes a shield tunnel 1, a mattress layer 2 is provided on the outside of the shield tunnel 1, grouting holes connected to the mattress layer 2 are provided on the inner wall of the shield tunnel 1, and cement soil piles extending along the radial direction of the shield tunnel 1 are provided on the outside of the mattress layer 2, and the cement soil piles are connected to the mattress layer 2 as a whole.

[0040] In this embodiment, a synchronous grouting layer 3 is provided on the outer wall of the shield tunnel 1. The cushion layer 2 is located on the outer wall of the synchronous grouting layer 3. The synchronous grouting layer 3, the cushion layer 2, and the cement-soil piles are integrally connected. The shield tunnel 1 is formed by a plurality of shield segments. The synchronous grouting layer 3 is constructed simultaneously with the shield tunnel 1. The cushion layer 2 is located on the outer wall of the synchronous grouting layer 3. The synchronous grouting layer 3 improves the connection strength between the cushion layer 2 and the shield tunnel 1, further enhancing the reinforcement strength of the shield tunnel 1's reinforcement device.

[0041] Specifically, such as Figure 1 、 Figure 2 As shown, the cement-soil piles include vertical cement-soil piles 4 and diagonal cement-soil piles 5, both of which are integrally connected to the cushion layer 2. The vertical cement-soil piles 4 and diagonal cement-soil piles 5 increase the reinforcement depth, reduce the difficulty of treating the deep, soft soil beneath the shield tunnel 1, minimize grouting disturbance, and uniformly reinforce the outer wall of the shield tunnel 1.

[0042] When only the difficulty of handling the deep, soft soil beneath the shield tunnel 1 is desired, the cross-section of the cushion layer 2 is semicircular, and the cushion layer 2 is located at the bottom of the shield tunnel 1. The cushion layer 2 comprises multiple lower cushion layer units located at the lower portion of the outer wall of the shield tunnel 1. Each lower cushion layer unit is provided with a vertical cement pile 4 and inclined cement piles 5 symmetrically arranged on either side of the vertical cement pile 4. There is at least one inclined cement pile 5 on either side of the vertical cement pile 4. When only the difficulty of handling the deep, soft soil beneath the shield tunnel 1 is desired, the cross-section of the upper cushion layer unit is semicircular, achieving the purpose of deformation control.

[0043] Example 5, as Figure 3 A shield tunnel 1 reinforcement device shown includes a shield tunnel 1, a mattress layer 2 is provided on the outside of the shield tunnel 1, grouting holes connected to the mattress layer 2 are provided on the inner wall of the shield tunnel 1, and cement soil piles extending along the radial direction of the shield tunnel 1 are provided on the outside of the mattress layer 2, and the cement soil piles are connected to the mattress layer 2 as a whole.

[0044] In this embodiment, a synchronous grouting layer 3 is provided on the outer wall of the shield tunnel 1. The cushion layer 2 is located on the outer wall of the synchronous grouting layer 3. The synchronous grouting layer 3, the cushion layer 2, and the cement-soil piles are integrally connected. The shield tunnel 1 is formed by a plurality of shield segments. The synchronous grouting layer 3 is constructed simultaneously with the shield tunnel 1. The cushion layer 2 is located on the outer wall of the synchronous grouting layer 3. The synchronous grouting layer 3 improves the connection strength between the cushion layer 2 and the shield tunnel 1, further enhancing the reinforcement strength of the shield tunnel 1's reinforcement device.

[0045] Specifically, the cement-soil piles include vertical cement-soil piles 4 and diagonal cement-soil piles 5, each integrally connected to the cushion layer 2. These piles significantly increase the reinforcement depth, reduce the difficulty of handling the deep, soft soil beneath the shield tunnel 1, minimize grouting disturbances, and evenly reinforce the outer wall of the shield tunnel 1.

[0046] like Figure 3 As shown, when the deformation of the shield tunnel 1 is strictly controlled, the cross-section of the cushion layer 2 is annular. The cushion layer 2 includes multiple lower cushion layer units located at the lower portion of the outer wall of the shield tunnel 1. A vertical cement soil pile 4 is disposed on the outer side of the lower cushion layer unit, and inclined cement soil piles 5 are symmetrically arranged on both sides of the vertical cement soil pile 4. There is at least one inclined cement soil pile 5 on either side of the vertical cement soil pile 4. The cushion layer 2 also includes multiple upper cushion layer units located at the upper portion of the outer wall of the shield tunnel 1. The multiple upper cushion layer units are arranged and connected along the axis of the shield tunnel 1. A vertical cement soil pile 4 is disposed on the outer side of the upper cushion layer unit, and inclined cement soil piles 5 are symmetrically arranged on both sides of the vertical cement soil pile 4. There is at least one inclined cement soil pile 5 on either side of the vertical cement soil pile 4. When the deformation of the shield tunnel 1 is strictly controlled, the cross section of the upper cushion layer unit and the cross section of the lower cushion layer unit are aligned to form a ring shape, thereby strengthening the purpose of deformation control.

[0047] The existing technology suffers from a limited reinforcement depth, making it difficult to handle the deep soft soil beneath the tunnel. This technical solution addresses the issue of insufficient reinforcement depth at the bottom of shield tunnel 1. The cement-soil piles formed by the TJS construction method can meet the requirements for construction within deep soft soil layers. The existing technology also suffers from the significant disturbance caused by grouting construction. This technical solution can address the significant disturbance to the surrounding soil caused by construction outside shield tunnel 1, reducing the risk of deformation of shield tunnel 1. The TJS method can dynamically adjust the slurry discharge rate and in-hole pressure, precisely controlling the boundaries of the cut soil, minimizing the impact of construction on the structure of shield tunnel 1 and the surrounding environment, and achieving micro-disturbance control throughout the entire process. The existing technology also suffers from the difficulty in controlling the quality of the reinforcement. This technical solution can address the issue of uneven quality control of cement-soil piles. The cement-soil piles formed by the TJS construction method are reliable and uniform in quality, with a large reinforcement depth, and their diameter and strength are essentially consistent along the depth direction.

[0048] The inner diameter of shield tunnel 1 is typically greater than 5.0m and is assembled from shield segments constructed using the shield method. The synchronous grouting layer 3 is generally 100mm to 150mm thick and is constructed simultaneously with shield tunnel 1. The thickness of the cushion layer 2 is generally not less than 0.5 times the maximum diameter of the cement soil pile. The cement soil piles consist of vertical cement soil piles 4 and inclined cement soil piles 5. The cement soil length of the cement soil piles generally does not exceed 20m. The diameter of the vertical cement soil piles 4 is 800mm to 1500mm, and the diameter of the inclined cement soil piles 5 is 600mm to 1200mm, with an inclination angle greater than 30°. The synchronous grouting layer 3, cushion layer 2, and cement soil piles are all made of cement soil, and the cement strength grade is generally not less than 42.5 ordinary Portland cement.

[0049] The distribution pattern of cement soil piles in shield tunnel 1 is briefly described as follows:

[0050] The distribution pattern of cement-soil piles outside the shield tunnel 1 can be designed according to actual project needs. When used for vertical deformation control, the cement-soil piles should be arranged in an overall symmetrical and balanced manner. One vertical cement-soil pile 4 and two oblique cement-soil piles 5 can be arranged for each cushion layer unit. When reinforcement requirements are higher, cement-soil piles should be appropriately added based on the number and location of grouting holes reserved in the shield segments of the shield tunnel 1. One vertical cement-soil pile 4 and four oblique cement-soil piles 5 can be arranged for each cushion layer unit. When requirements for protecting the surrounding environment are higher or when strict control is required for tunnel deformation, cement-soil can be driven into the top and circumferential directions of the shield tunnel 1 to achieve deformation control. For example, two vertical cement-soil piles 4 and multiple oblique cement-soil piles 5 can be arranged for each cushion layer unit.

[0051] Cement-soil piles can be arranged in the form of each cushion layer unit, interval cushion layer unit arrangement and plum blossom arrangement according to design requirements. The specific arrangement should be determined comprehensively based on the calculation results.

[0052] The specific embodiments described above are only preferred implementations of the present invention and are not intended to limit the specific scope of implementation of the present invention. All equivalent changes made to the shape and structure of the present invention should be included in the scope of protection of the present invention.

Claims

1. A shield tunnel reinforcement device, comprising a shield tunnel, characterized in that: A cushion layer is provided on the outside of the shield tunnel, and grouting holes communicating with the cushion layer are provided on the inner wall of the shield tunnel. Cement soil piles extending along the radial direction of the shield tunnel are provided on the outside of the cushion layer, and the cement soil piles are connected to the cushion layer as a whole; there are multiple vertical cement soil piles, and the multiple vertical cement soil piles are arranged along the axis direction of the shield tunnel; the cross-section of the cushion layer is semicircular, and the cushion layer includes multiple lower cushion layer units located at the lower part of the outer wall of the shield tunnel, and a vertical cement soil pile is provided on the outside of the lower cushion layer unit, as well as oblique cement soil piles symmetrically arranged on both sides of the vertical cement soil pile according to the vertical cement soil pile.

2. A shield tunnel reinforcement device according to claim 1, characterized in that: A synchronous grouting layer is provided on the outer side wall of the shield tunnel, the cushion layer is located on the outer side wall of the synchronous grouting layer, and the synchronous grouting layer, the cushion layer and the cement soil pile are connected as a whole.

3. A shield tunnel reinforcement device according to claim 2, characterized in that: The cement soil piles include vertical cement soil piles and oblique cement soil piles, and the vertical cement soil piles and oblique cement soil piles are both connected to the cushion layer as a whole.

4. A shield tunnel reinforcement device according to claim 3, characterized in that: There are multiple inclined cement-soil piles, and the inclined cement-soil piles are respectively arranged on both sides of the same plane where the central axes of the multiple vertical cement-soil piles are located.

5. The shield tunnel reinforcement device according to claim 4, characterized in that: The oblique cement-soil piles are symmetrically arranged according to the same plane where the central axes of the plurality of vertical cement-soil piles are located.

6. A shield tunnel reinforcement device according to claim 4 or 5, characterized in that: The oblique cement-soil piles located on either side of the same plane where the central axes of the plurality of vertical cement-soil piles are located are arranged along the axis direction of the shield tunnel.

7. The shield tunnel reinforcement device according to claim 3, characterized in that: The oblique cement-soil piles located on both sides of the same plane where the central axes of the plurality of vertical cement-soil piles are located are arranged in a plum blossom shape.

8. A shield tunnel reinforcement device according to claim 1, 2, 3, 4 or 5, characterized in that: The number of the oblique cement soil pile on any one side of the vertical cement soil pile is at least one.

9. The shield tunnel reinforcement device according to claim 8, characterized in that: The cushion layer also includes a plurality of upper cushion layer units located on the upper part of the outer wall of the shield tunnel. The plurality of upper cushion layer units are arranged along the axial direction of the shield tunnel and connected as a whole. A vertical cement soil pile and inclined cement soil piles symmetrically arranged on both sides of the vertical cement soil pile are provided on the outside of the upper cushion layer unit. The number of inclined cement soil piles on either side of the vertical cement soil pile is at least one.

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