A method for testing water and soil pressure of a shield tunnel

Abstract

The application discloses a kind of shield tunnel water and soil pressure test methods, by installing component, the pipe piece water and soil pressure test component is welded on the reinforcement framework of each pipe piece block of shield tunnel, after the measuring surface of control test component is flush with the outer arc surface of pipe piece mold, pouring concrete again, it can avoid test component to be washed and cause damage or fall off when shield tail is out of pipe piece, simultaneously, test component cable line leads to hiding line box and is protected, and the part cable line that is directly contacted with concrete during subsequent pouring is wrapped using sleeve pipe, buffer, insulation is played.The application can achieve the purpose that test component is pre-buried before pipe piece pouring and assembly, and greatly ensure the survival rate of instrument and reduce the influence on pipe piece quality.

Description

Technical Field

[0001] This invention belongs to the field of underground space engineering technology, specifically relating to a method for testing water and soil pressure in shield tunnels. Background Technology

[0002] Subway tunnel construction includes shield tunneling, cut-and-cover, and mining methods, among which shield tunneling is widely used due to its advantages such as high efficiency, safety, and minimal disruption to surface traffic. Clearly defining the magnitude and distribution pattern of loads on the tunnel lining is a prerequisite for shield tunnel lining design. Existing tunnel lining structural design and calculation methods generally employ a modified conventional method. However, some scholars have pointed out problems with this modified conventional method in calculating surrounding rock pressure in complex strata, and it often leads to an overly conservative design due to the increased safety factor. Therefore, it is crucial to investigate whether the traditional modified conventional method load system and existing shield tunnel load calculation theories can adequately adapt to the actual engineering of subway shield tunnels in various geological formations. To avoid significant safety hazards and economic losses, it is necessary to conduct research on the load action mode of subway shield tunnels (i.e., the water and soil pressure on the tunnel segments). This will not only lay a theoretical foundation for further research on the stress response law of shield tunnel structures but also provide better theoretical and practical basis for subsequent tunnel construction in my country.

[0003] To investigate the soil and water pressure experienced by subway shield tunnels, on-site testing is undoubtedly the most valuable method. Common soil pressure testing components include resistive, vibrating wire, and piezoresistive soil pressure sensors, as well as flexible soil pressure gauges. Water pressure testing components are similar. However, resistive and piezoresistive soil pressure sensors, due to limitations in their range and construction principles, are suitable for indoor geotechnical model tests and centrifugal model tests, and often require a certain level of on-site power, making them unsuitable for long-term monitoring. Flexible soil pressure gauges offer high accuracy and a large range, making them suitable for on-site testing, but their large surface area may affect the shape and quality of the tunnel segments, and they are expensive. Currently, vibrating wire soil pressure sensors are more widely used in tunnel engineering on-site testing, primarily in highway and railway tunnels. This is because in these tunnels, the testing instrument can be directly buried between the surrounding rock and the initial lining, and the instrument's cable can be extended from the outer surface of the lining to the inner side for measurement. For shield tunnels, the shield machine is a device that excavates tunnels under the protection of a steel shell. It uses a cutterhead and cutting tools to rotate and cut the strata. The shield shell and segments support the surrounding rock to prevent collapse into the tunnel. Precast concrete segments are assembled inside the shell, and grouting is performed simultaneously at the tail of the shield. Due to this unique characteristic, components cannot be installed after the lining of highway and railway tunnels is completed, as the back wall of the segments has already been grouted and is in direct contact with the soil and rock when the tail of the shield emerges. There is no extra space to install components. Therefore, components must be installed before the segments are transported to the shield machine for excavation and assembly. The gap between the segments and the steel shell of the shield machine is very small. If components are installed on the outer surface of the segments, they are easily eroded when the tail of the shield emerges from the segments, which can lead to damage or even detachment of the instruments.

[0004] Therefore, if a method for testing the water and soil pressure of shield tunnels can be invented, the above problems will be solved, and the survival rate of the instrument can be greatly guaranteed and the impact on the quality of the tunnel segments can be reduced. Summary of the Invention

[0005] The purpose of this invention is to provide a method for testing water and soil pressure in shield tunnels. Based on the special characteristics of shield tunnel construction, the testing components are pre-embedded before the segment casting and assembly, thereby overcoming the shortcomings of the prior art.

[0006] To achieve the above objectives, the technical solution adopted by this invention is: a method for testing soil and water pressure in shield tunnels, employing a pre-embedded device. The pre-embedded device includes a shield tunnel segment assembly, a testing assembly, an installation assembly, and a cable concealment box. The shield tunnel segment assembly includes multiple segment reinforcement skeletons, including arch crown segment reinforcement skeletons and arch waist and arch bottom segment reinforcement skeletons. The multiple segment reinforcement skeletons are cast and assembled to form a segment ring. The testing assembly includes an earth pressure gauge and a water pressure gauge, which are positioned at the test points. The installation assembly includes an earth pressure gauge mounting box and a water pressure gauge mounting cylinder. The testing method includes the following steps:

[0007] Step (1): Hoist the arch top segment steel reinforcement skeleton and the arch waist and arch bottom segment steel reinforcement skeleton onto the segment mold, and then weld the installation components onto the arch top segment steel reinforcement skeleton and the arch waist and arch bottom segment steel reinforcement skeleton. The welding position is the test point. Before welding, adjust the welding height or add steel reinforcement pads to ensure that the measuring surface of the test component is flush with the outer arc surface of the segment mold after the concrete is poured. Then weld the wire box to the arch top segment steel reinforcement skeleton and the arch waist and arch bottom segment steel reinforcement skeleton. Similarly, adjust the welding height to ensure that the bottom of the wire box is in close contact with the inner arc surface of the segment mold after the concrete is poured.

[0008] Step (2): Fix the test components to the installation components by tightening the bolts, then tie the test component cable along the bottom of the steel bar and lead it to the cable box, pass it through the top reserved hole into the cable box, and apply water-swellable sealant near the top reserved hole.

[0009] Step (3): Pre-attach multiple layers of plastic film with a certain degree of adhesion to the top measuring surface of the test assembly;

[0010] Step (4): Pour concrete into the steel reinforcement cage of the pipe segment. During the pouring process, the measuring surface of the test component must be exposed. After the pouring is completed, grind the concrete on the outside of the pipe segment near the measuring surface of the test component appropriately. After grinding, clean the surface with industrial alcohol and apply an appropriate amount of waterproof material and epoxy glue.

[0011] Step (5): Curing the cast pipe segments, removing the concrete on the bottom surface of the cable box after curing, pulling out the internal cable for connection, assembling the pipe segments into a complete pipe ring, and finally transporting the pipe ring to the actual shield tunnel project for on-site testing, tearing off the plastic film on the measuring surface of the test component, and then using an intelligent reading instrument for measurement.

[0012] The beneficial effects of this invention are as follows: By welding the segment water and soil pressure testing component to the steel reinforcement frame of each segment of the shield tunnel using an installation assembly, and ensuring the measuring surface of the testing component is flush with the outer arc surface of the segment mold before concrete pouring, the invention avoids damage or detachment of the testing component due to erosion when it exits the segment at the shield tail. Simultaneously, the testing component's cable is protected by a cable management box, and the portion of the cable in direct contact with the concrete during subsequent pouring is encased in conduit for buffering and insulation. This invention allows for the pre-installation of testing components before segment pouring and assembly, significantly improving instrument survivability and minimizing impact on segment quality.

[0013] Preferably, the earth pressure gauge is disc-shaped with its top surface serving as the measuring surface, while the water pressure gauge is a slender cylinder with a permeable stone on its top measuring surface.

[0014] Preferably, the earth pressure gauge mounting box is a rectangular box with a closed bottom and an open top. The rectangular box includes adjustable bolts arranged on three sides and a wire groove arranged on another side. The side length of the rectangular box is slightly larger than the diameter of the earth pressure gauge, controlled within 1mm-3mm.

[0015] Preferably, the water pressure gauge mounting cylinder is a weldable hollow cylindrical cylinder. The length and cross-sectional diameter of the weldable hollow cylindrical cylinder are slightly larger than the length and cross-sectional diameter of the water pressure gauge, controlled within 1mm-3mm. The weldable hollow cylindrical cylinder also includes two adjustable bolts arranged on the side.

[0016] Preferably, the cable concealment box is a weldable cylindrical tube with a top plate but no bottom plate. The top plate has pre-drilled holes corresponding to the number of cables in the test component, and the cable concealment box is equipped with a matching sealing cover.

[0017] Preferably, the test points should avoid the handholes and joints of each pipe segment.

[0018] Preferably, before binding the test component cable in step (2), the part of the cable that will come into direct contact with the concrete during subsequent pouring is wrapped with an insulating PVC sleeve or a rubber sleeve. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1A schematic diagram of the water and soil pressure device pre-embedded in the steel reinforcement skeleton of the arch block segment according to an embodiment of the present invention;

[0021] Figure 2 This is a schematic diagram of the water and soil pressure device pre-embedded in the steel reinforcement skeleton of the arch waist and arch bottom block segments according to an embodiment of the present invention.

[0022] Figure 3 This is a schematic diagram of the earth pressure gauge structure according to an embodiment of the present invention;

[0023] Figure 4 This is a schematic diagram of the permeable stone structure according to an embodiment of the present invention;

[0024] Figure 5 This is a schematic diagram of the water pressure gauge structure according to an embodiment of the present invention;

[0025] Figure 6 This is a schematic diagram of the structure of the earth pressure gauge mounting box according to an embodiment of the present invention;

[0026] Figure 7 This is a schematic diagram of the adjustable bolt structure according to an embodiment of the present invention;

[0027] Figure 8 This is a schematic diagram of the water pressure gauge mounting cylinder structure according to an embodiment of the present invention;

[0028] Figure 9 This is a schematic diagram of the cable-storage box according to an embodiment of the present invention;

[0029] Figure 10 This is a schematic diagram of the test device of the present invention after it has been pre-embedded in the steel reinforcement skeleton of the arch block segment and is ready for concrete pouring.

[0030] Figure 11 This is a schematic diagram of the test device of the present invention after pre-embedding it on the steel reinforcement skeleton of the arch waist and arch bottom block segments, before pouring concrete.

[0031] Figure 12 This is a schematic diagram of the pre-embedded testing device and the completed concrete pouring structure according to an embodiment of the present invention.

[0032] Figure 13 This is a schematic diagram of the pre-embedded test device and the assembled segment ring after the concrete pouring is completed, according to an embodiment of the present invention.

[0033] Among them: 1 is the shield tunnel segment assembly, 2 is the testing assembly, 3 is the installation assembly, 4 is the cable concealment box, 5 is the arch top segment steel reinforcement skeleton, 6 is the arch waist and arch bottom segment steel reinforcement skeleton, 7 is the welded steel reinforcement, 8 is the earth pressure gauge, 9 is the water pressure gauge, 10 is the cable, 11 is the earth pressure gauge mounting box, 12 is the water pressure gauge mounting cylinder, 13 is the measuring surface of the testing assembly, 14 is the permeable stone, 15 is the rectangular box, 16 is the adjustable bolt, 17 is the cable channel, 18 is the nut, 19 is the nut, 20 is the weldable hollow cylindrical tube, 21 is the weldable cylindrical tube, 22 is the reserved opening, 23 is the sealing cover, 24 is the outer arc surface of the segment mold, and 25 is the sleeve. Detailed Implementation

[0034] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain embodiments of the present invention, and should not be construed as limiting the present invention.

[0035] In the description of the embodiments of the present invention, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention.

[0036] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of the present invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0037] In the embodiments of the present invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of the present invention according to the specific circumstances.

[0038] The present invention will be further described in detail with reference to the accompanying drawings.

[0039] The segmentation method for shield tunnels in my country is determined comprehensively based on the geological conditions, load conditions, structural characteristics, and manufacturing, transportation, and assembly processes of the tunnel. For shield tunnels with smaller outer diameters, a typical segmentation pattern is 5+1. For shield tunnels with outer diameters exceeding 10 meters, each ring of segments is mostly divided into 8 to 10 segments, with typical segmentation patterns including 7+1 and 9+1. Based on this, this invention selects the typical 5+1 segmentation pattern for shield tunnels as an example for detailed description.

[0040] Please refer to Figure 1 As shown, an embodiment of the present invention provides a method for testing the water and soil pressure of a shield tunnel, which uses a pre-embedded device. The pre-embedded device includes a shield segment assembly 1, a testing assembly 2, an installation assembly 3, and a cable concealment box 4. The shield segment assembly 1 includes multiple segment reinforcement skeletons, including a crown segment reinforcement skeleton 5 and a waist and bottom segment reinforcement skeleton 6. The multiple segment reinforcement skeletons are cast and assembled to form a segment ring.

[0041] Specifically, in the embodiments of the present invention, there is only one arch apex segment reinforcement cage 5, and five arch waist and arch bottom segment reinforcement cages 6, forming a 5+1 segment pattern. Each segment reinforcement cage is composed of prefabricated and welded wire cages, which are arc-shaped overall, with rectangular cross-sections at both ends. After concrete is poured, they are assembled to form a complete segment ring.

[0042] The test component 2 includes an earth pressure gauge 8 and a water pressure gauge 9, which are installed at the test points; each of the earth pressure gauge 8 and the water pressure gauge 9 is equipped with a cable 10.

[0043] The installation assembly 3 includes a soil pressure gauge mounting box 11 and a water pressure gauge mounting cylinder 12.

[0044] Specifically, in the embodiments of the present invention, since the central angle corresponding to the arch top segment steel reinforcement skeleton 5 is relatively small, only one measuring point is usually arranged; while the central angle corresponding to the arch waist block and arch bottom block steel reinforcement skeleton 6 is relatively large, two measuring points are usually arranged, that is, two sets of test components 2 and installation components 3 need to be prepared accordingly.

[0045] The testing method includes the following steps:

[0046] Step (1): Please refer to Figure 10 and Figure 11As shown, the arch apex segment steel reinforcement skeleton 5 and the arch waist and arch bottom segment steel reinforcement skeleton 6 are hoisted onto the segment mold. Then, the installation component 3 is welded to each arch apex segment steel reinforcement skeleton and the arch waist 5 and arch bottom segment steel reinforcement skeleton 6. The welding position is the test point. Before welding, the welding height is adjusted or steel bars 7 are added to raise the height to ensure that the measuring surface 13 of the test component 2 is flush with the outer arc surface 24 of the segment mold after the concrete is poured. Then, the cable box 4 is welded to each arch apex segment steel reinforcement skeleton and the arch waist 5 and arch bottom segment steel reinforcement skeleton 6. Similarly, the welding height is adjusted to ensure that the bottom of the cable box 4 is in close contact with the inner arc surface 25 of the segment after the concrete is poured.

[0047] Step (2): Fix the test component 2 to the installation component 3 by tightening the bolts 16. Then, tie the cable of the test component 2 along the bottom of the steel bar and lead it to the cable box 4. Pass it through the top reserved hole 22 into the cable box 4, and apply water-swellable sealant near the top reserved hole 22.

[0048] Step (3): Multiple layers of plastic film with a certain degree of adhesion are pre-attached to the top measuring surface 13 of the test component 2;

[0049] Step (4): Pour concrete into the steel reinforcement cage of the pipe segment. During the pouring process, it is necessary to ensure that the measuring surface 13 of the test component 2 is exposed. After the pouring is completed, the concrete on the outside of the pipe segment near the measuring surface 13 of the test component 2 is properly ground. After grinding, the surface is cleaned with 95% industrial alcohol and an appropriate amount of waterproof material and epoxy glue are applied.

[0050] Step (5): Refer to Figure 12 As shown, the cast pipe segments are cured. After curing, the concrete on the bottom surface of the junction box 4 is removed, and the internal cable 10 is pulled out for wiring. Then, the pipe segments are assembled into a complete pipe ring. The pipe ring is referenced. Figure 13 As shown. Finally, when the tunnel segment is transported to the actual shield tunnel project for on-site testing, the plastic film on the measuring surface 13 of the test component 2 is removed, and then the intelligent reading instrument is connected for measurement.

[0051] The test points must avoid the handholes and joints of each pipe segment.

[0052] This can be explained by the fact that the rectangular sections of the arch crown segment reinforcement cage 5, the arch waist segment reinforcement cage 6, and the arch bottom segment reinforcement cage 7 are assembled into a segment ring after pouring. A joint is formed at the splicing point of each adjacent segment reinforcement cage. The stiffness of the shield tunnel segment ring will be reduced at the joint, making the segment ring very vulnerable and prone to damage. Furthermore, in actual engineering, grouting and hoisting manholes are pre-drilled inside the segments. Therefore, to ensure segment quality, the test points must avoid the manholes and joint locations of each segment.

[0053] Before binding the cable 10 of the test component 2 in step (2), the part of the cable that will come into direct contact with the concrete during subsequent pouring is wrapped with insulating PVC or rubber sleeve 25.

[0054] Specifically, because the concrete is poured from top to bottom when pouring concrete into the steel reinforcement cage of the pipe segment, and because a large amount of concrete is required and the concrete itself is heavy, the cable that comes into direct contact with the concrete during subsequent pouring is wrapped with a 25mm conduit to buffer and insulate it, so as to ensure the survival rate of the instrument.

[0055] Please refer to Figures 3-5 As shown, the earth pressure gauge 8 is disc-shaped, and the top surface of the earth pressure gauge 8 is the measuring surface 13. The water pressure gauge 8 is a slender cylinder, and the top measuring surface 13 is provided with a permeable stone 14.

[0056] Please refer to Figures 6-7 As shown, the earth pressure gauge mounting box 11 is a rectangular box 15 with a closed bottom and an open top. The rectangular box 15 includes adjustable bolts 16 arranged on three sides and a wire groove 17 arranged on another side. The side length of the rectangular box 15 is slightly larger than the diameter of the earth pressure gauge, controlled between 1mm and 3mm.

[0057] The adjustable bolt 16 includes a nut 18 and a bolt 19, and is adjusted using an internal hex wrench.

[0058] Please refer to Figure 8 As shown, the water pressure gauge mounting cylinder 12 is a weldable hollow cylindrical cylinder 20. The length and cross-sectional diameter of the weldable hollow cylindrical cylinder 20 are slightly larger than the length and cross-sectional diameter of the water pressure gauge 9, and are controlled within 1mm-3mm. The weldable hollow cylindrical cylinder 20 also includes two adjustable bolts 16 arranged on the side.

[0059] Please refer to Figure 9 As shown, the cable concealment box 4 is a weldable cylindrical tube 21 with a top plate but no bottom plate. The top plate has pre-reserved openings 22 corresponding to the number of cables of the test component 3. The cable concealment box 4 is equipped with a matching sealing cover 23.

[0060] Specifically, the sealing cover 23 is installed to prevent concrete from entering the cable box 4 due to grouting when pouring concrete into the steel reinforcement cage of the pipe segment. After the concrete is poured, the sealing cover is opened to ensure that the cable 10 inside can be pulled out smoothly.

[0061] In summary, the water and soil pressure testing method for shield tunnels provided by this invention has the following beneficial effects:

[0062] This invention welds the water and soil pressure testing components to the steel reinforcement framework of each tunnel segment using an installation assembly. By ensuring the measuring surface of the testing component is flush with the outer arc surface of the segment mold before concrete pouring, the component is protected from damage or detachment due to erosion during the shield tail's exit from the segment. Simultaneously, the testing component's cable is protected by a concealed junction box, and the portion of the cable in direct contact with the concrete during subsequent pouring is encased in conduit for buffering and insulation. This invention allows for the pre-installation of testing components before segment pouring and assembly, significantly improving instrument survivability and minimizing impact on segment quality.

[0063] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0064] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A method for testing soil and water pressure in shield tunnels, characterized in that: An embedded device is used, comprising a shield tunnel segment assembly, a testing assembly, an installation assembly, and a cable concealment box. The shield tunnel segment assembly includes multiple segment reinforcement skeletons, including a crown segment reinforcement skeleton, a waist segment reinforcement skeleton, and a bottom segment reinforcement skeleton. These multiple reinforcement skeletons are cast and assembled to form a segment ring. The testing assembly includes an earth pressure gauge and a water pressure gauge, which are positioned at the test points. The installation assembly includes an earth pressure gauge mounting box and a water pressure gauge mounting cylinder. The testing method includes the following steps: Step (1): Hoist the arch top segment steel reinforcement skeleton and the arch waist and arch bottom segment steel reinforcement skeleton onto the segment mold, and then weld the installation components onto the arch top segment steel reinforcement skeleton and the arch waist and arch bottom segment steel reinforcement skeleton. The welding position is the test point. Before welding, adjust the welding height or add steel reinforcement pads to ensure that the measuring surface of the test component is flush with the outer arc surface of the segment mold after the concrete is poured. Then weld the wire box onto the arch top segment steel reinforcement skeleton and the arch waist and arch bottom segment steel reinforcement skeleton. Similarly, adjust the welding height to ensure that the bottom of the wire box is in close contact with the inner arc surface of the segment mold after the concrete is poured. Step (2): Fix the test components to the installation components by tightening the bolts, then tie the test component cable along the bottom of the steel bar and lead it to the cable box, pass it through the top reserved hole into the cable box, and apply water-swellable sealant near the top reserved hole. Step (3): Pre-attach multiple layers of adhesive plastic film to the top measuring surface of the test assembly; Step (4): Pour concrete into the steel reinforcement cage of the pipe segment. During the pouring process, the measuring surface of the test component must be exposed. After the pouring is completed, the concrete on the outside of the pipe segment near the measuring surface of the test component is properly ground. After grinding, the surface is cleaned with industrial alcohol and coated with waterproof material and epoxy glue. Step (5): Curing the cast pipe segments, after curing, removing the concrete on the bottom surface of the cable box, pulling out the internal cable for connection, assembling the pipe segments into a complete pipe ring, and finally transporting the pipe ring to the actual shield tunnel project for on-site testing, tearing off the plastic film on the measuring surface of the test component, and then using an intelligent reading instrument for measurement.

2. The method for testing water and soil pressure in shield tunnels according to claim 1, characterized in that: The earth pressure gauge is disc-shaped with its top surface serving as the measuring surface. The water pressure gauge is a slender cylinder with a permeable stone on its top measuring surface.

3. The method for testing water and soil pressure in shield tunnels according to claim 1, characterized in that: The earth pressure gauge mounting box is a rectangular box with a closed bottom and an open top. The rectangular box includes adjustable bolts arranged on three sides and a wire groove arranged on another side. The side length of the rectangular box is 1mm-3mm larger than the diameter of the earth pressure gauge.

4. The method for testing water and soil pressure in shield tunnels according to claim 1, characterized in that: The water pressure gauge mounting cylinder is a weldable hollow cylindrical cylinder. The length and cross-sectional diameter of the weldable hollow cylindrical cylinder are both 1mm-3mm larger than the length and cross-sectional diameter of the water pressure gauge. The weldable hollow cylindrical cylinder also includes two adjustable bolts arranged on the side.

5. The method for testing water and soil pressure in shield tunnels according to claim 1, characterized in that: The cable concealment box is a weldable cylindrical tube with a top plate but no bottom plate. The top plate has pre-drilled holes corresponding to the number of cables in the test component, and the cable concealment box is equipped with a matching sealing cover.

6. The method for testing water and soil pressure in shield tunnels according to claim 1, characterized in that: The test points should avoid the handholes and joints of each pipe segment.

7. The method for testing water and soil pressure in shield tunnels according to claim 1, characterized in that: Before binding the test component cable in step (2), the part of the cable that will come into direct contact with the concrete during subsequent pouring is wrapped with a sleeve.

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