Micro-monitoring system and method for stratum in shield tunnel construction process

Abstract

This invention relates to the field of shield tunneling ground monitoring technology, and particularly to a ground micro-monitoring system and method during shield tunnel construction. A transverse borehole is set between the shield tunnel and sensitive structures, directly above the shield tunnel. Backfill material is placed inside the transverse borehole, and an elastic tube is installed inside the backfill material. An anchor head is installed at the end of the transverse borehole, and the elastic tube is fixedly connected to the anchor head. Compared with existing technologies, this invention can achieve overall monitoring of sensitive structures, avoiding local monitoring achieved through multi-point drilling, making the monitoring values ​​more representative. When ground settlement occurs, the elastic tube, which can undergo elastic deformation, undergoes random continuous bending following the settlement. A linear object inside the elastic tube pulls a linear object outside the transverse borehole into the elastic tube. By obtaining the amount of traction on the linear object, overall monitoring of settlement in the shield tunnel area is achieved. The linear object can be a pull rope or a thin steel wire rope.

Description

Technical Field

[0001] This invention relates to the field of shield tunneling ground monitoring technology, specifically to a ground micro-monitoring system and method during shield tunnel construction. Background Technology

[0002] When shield tunnels pass under sensitive structures, such as high-voltage power towers and highways, they will disturb the strata. It is necessary to monitor such disturbances to provide quantitative basis for differentiated construction control and risk prevention.

[0003] The publication number CN210464435U discloses a deformation monitoring system for shield tunneling in sandy and gravelly strata with strong disturbance. In order to reduce the lag in settlement transmission, it uses a method of vertically drilling at intervals and installing monitoring sensors in the holes to monitor the strata with sensitive structures.

[0004] However, for inherent sensitive structures, drilling by damaging the original ground is not very suitable (for example, drilling by damaging the road surface requires subsequent repairs). Drilling near sensitive structures does not allow for effective monitoring of the impact of the tunnel boring machine on the sensitive structures.

[0005] Most importantly, the multi-point drilling method in the aforementioned patents cannot achieve continuous monitoring, resulting in incomplete monitoring.

[0006] Therefore, a ground micro-monitoring system and method for the shield tunnel construction process are proposed to address the above-mentioned problems. Summary of the Invention

[0007] The purpose of this invention is to provide a ground micro-monitoring system and method during shield tunnel construction. Before the shield machine passes through a sensitive structure, a horizontal borehole is drilled between the pre-designed shield tunnel and the sensitive structure, and a channel that can follow the ground settlement is formed inside the borehole. When the shield machine passes through, the length of the linear object in the channel is observed to reflect the overall settlement change on the upper side when the shield machine passes through the sensitive structure.

[0008] To achieve the above objectives, the present invention provides the following technical solution: a ground micro-monitoring system during shield tunnel construction, comprising a transverse borehole, wherein the transverse borehole is located between the shield tunnel and the sensitive structure, and is located on the upper side of the shield tunnel;

[0009] The inside of the transverse borehole is backfilled with backfill material, and an elastic tube is installed inside the backfill material. An anchor head is installed at the end of the transverse borehole. The elastic tube is fixedly connected to the anchor head. A linear object is slidably connected inside the elastic tube. The end of the linear object near the anchor head can be fixed.

[0010] In this invention, a transverse borehole is first created using a drill rod, and the created transverse borehole is temporarily supported by a sleeve. The sleeve is on the outside of the drill rod, and the drill rod is in front of it. The sleeve and the drill rod advance simultaneously to achieve timely support of the transverse borehole by the sleeve. The rotation and advance method of the drill rod is existing technology and will not be elaborated here.

[0011] The sleeve is moved forward and backward by a sleeve conveyor. The sleeve conveyor is equipped with a rotatable drive disc. The drive disc is in close contact with the sleeve. The drive disc is driven to rotate by a motor, and the drive disc drives the sleeve to move forward and backward.

[0012] Then the anchor head is passed through the sleeve to the end of the transverse borehole, and finally the backfill material is filled into the inside of the transverse borehole through the pipe in a way from deep to shallow. The sleeve is continuously withdrawn while filling, and the pipe can be a flexible auger conveying pipe.

[0013] Compared with existing technologies, this invention can achieve overall monitoring of sensitive buildings, avoiding local monitoring achieved through multi-point drilling, and making the monitoring values ​​more representative.

[0014] When the strata settle, the elastic tube, which can undergo elastic deformation, will randomly bend continuously following the settlement. The linear object inside the elastic tube will pull the linear object outside the transverse borehole into the elastic tube. By obtaining the amount of traction of the linear object, the overall monitoring of the settlement in the shield tunnel area can be achieved. The linear object can be a pull rope or a thin steel wire rope.

[0015] The elastic tube has an elliptical cross-section with a wider upper side, allowing for a larger stress-bearing surface to settle along with the soil and rock mass.

[0016] As a preferred embodiment of the ground micro-monitoring system during the shield tunnel construction process of the present invention, the elastic tube consists of an outer friction layer, an elastic support ring, an inner sliding layer, and a channel from the outside to the inside, with the linear object set inside the channel.

[0017] The outer friction layer is used to increase the friction between the tube and the soil, ensuring that the elastic tube follows the movement of the surrounding soil.

[0018] The elastic support ring is used to protect the presence of the channel;

[0019] The channel is coated with lubricating oil to reduce the sliding friction of the wire.

[0020] As a preferred embodiment of the ground micro-monitoring system during the shield tunnel construction process of the present invention, the ground micro-monitoring system further includes a support frame. The top of the support frame is rotatably connected to a reel via a rotating shaft. The rotation of the reel is damped by a small damping force, which is only used to prevent the linear object from slackening. The other end of the linear object is wound around the outside of the reel. The rotation of the reel provides the traction of the linear object. A rotation sensor is provided at the rotating shaft of the reel to obtain the traction length of the linear object.

[0021] In this invention, the rotation sensor can obtain the number of rotations and rotation angle of the reel, and thus calculate the traction length of the linear object by multiplying the number of rotations by the circumference.

[0022] As a preferred embodiment of the ground micro-monitoring system in the shield tunnel construction process of the present invention, the backfill material is backfill soil or backfill mortar, which serves to support the rock and soil mass and to wrap the elastic tube.

[0023] After the backfill material is filled, the sleeve needs to be removed so that the elastic tube settles along with the surrounding soil.

[0024] As a preferred embodiment of the ground micro-monitoring system in the shield tunnel construction process of the present invention, the main material of the elastic tube is latex, which can be stretched and bent in response to the settlement of the rock and soil.

[0025] As a preferred embodiment of the ground micro-monitoring system during the shield tunnel construction process of the present invention, a battery and a controller are fixedly connected to the inner side of the anchor head, and an anchoring structure is provided at the anchor head. When the anchor head undergoes horizontal displacement, it will interfere with the traction of the linear object. The anchoring structure in the present invention is used to reduce the horizontal displacement of the anchor head and increase the accuracy of monitoring.

[0026] Since soil is not a good medium for wireless transmission, in this invention, the motor is controlled by a wired communication module and controller.

[0027] As a preferred embodiment of the ground micro-monitoring system during the shield tunnel construction process of the present invention, the anchoring structure includes a motor and an inner spiral component. The inner spiral component is fixedly connected to the inner side of the anchor head, and a spiral drill bit is spirally connected to the inner side of the inner spiral component. The motor is fixed to the inner side of the anchor head, and a hexagonal column is fixedly connected to the end of the motor's main shaft. The outer side of the hexagonal column is slidably connected to the inner side of the spiral drill bit. When the hexagonal column rotates, the spiral drill bit can rotate and screw into the inner side of the rock and soil mass.

[0028] In this invention, because the outer side of the hexagonal prism is slidably connected to the inner side of the auger drill bit, the rotation of the hexagonal prism will drive the auger drill bit to rotate. When the auger drill bit rotates, it will rise under the action of the inner auger, thereby entering the inner side of the rock and soil. The rotational entry method makes it easier to enter.

[0029] As a preferred embodiment of the ground micro-monitoring system during the shield tunnel construction process of the present invention, the inner side of the anchor head is provided with an inner cavity, and an elastic strip is installed on the inner side of the inner cavity. The elastic strip is made of smooth silicone. One end of the elastic strip is fixedly connected to a linear object, and a limit hole is opened on the inner side of the end of the elastic strip. An electric push rod is fixedly connected to the inner side of the anchor head, and a limit post is fixedly connected to the movable end of the electric push rod. In the initial state, the limit post is inserted into the limit hole to lock the elastic strip.

[0030] The elastic tube and elastic strip in this invention can also be installed on the lower side of the anchor head. The elastic strip is limited by the limiting post. After the moving end of the electric push rod rises, the limiting post and the limiting hole are decoupled. The elastic strip is pulled out of one side of the anchor head and into the inner side of the channel by dragging the linear object.

[0031] As a preferred embodiment of the ground micro-monitoring system in the shield tunnel construction process of the present invention, the linear object contains twisted electrical signal lines, which are used to realize control and electrical signal transmission. A communication module is fixedly connected to the inner side of the elastic strip, and strain gauges are adhered to the inner sides of both the upper and lower ends of the elastic strip. The two ends of the elastic strip are provided with guide surfaces to facilitate movement in the channel.

[0032] Pulling the wire allows the elastic strip to slowly pass through the channel. When the elastic strip passes the bending position of the elastic tube caused by ground settlement, the bending direction of the strain gauges on the upper and lower sides is inconsistent. The bending direction is identified by the inconsistency of the electrical signal changes of the strain gauges on the upper and lower sides, thereby realizing the uniform monitoring of settlement of sensitive structures on the upper side of the shield tunnel.

[0033] In this invention, the specific principle of reflecting the bending direction of the elastic strip by the change in electrical signals of the strain gauges on both the upper and lower sides is as follows:

[0034] When the elastic strip bends, one surface is stretched and the other surface is compressed. The strain on the upper and lower surfaces is approximately equal in magnitude but opposite in sign. The strain gauge attached to the upper surface is under tension, and its resistance increases; the strain gauge attached to the lower surface is under compression, and its resistance decreases. By measuring the signs of the resistance changes of these two strain gauges, it is possible to directly determine whether the elastic strip is bending upwards or downwards. This is existing technology and will not be elaborated further here.

[0035] The steps of the method for microscopic monitoring of the strata during shield tunnel construction are as follows:

[0036] Step 1: Installation. A transverse borehole is created using a drill rod. The borehole is first temporarily supported by a sleeve. Then, the anchor head is passed through the sleeve and pushed to the end of the borehole. Finally, backfill material is filled into the borehole from deep to shallow through a pipe. The sleeve is continuously removed while filling.

[0037] Step 2: During a single monitoring session, when ground subsidence occurs, the elastic tube, which can undergo elastic deformation, will randomly and continuously bend in response to the subsidence. The linear object inside the elastic tube will pull the linear object outside the transverse borehole into the elastic tube. By obtaining the amount of traction of the linear object, the overall monitoring of the shield tunnel area can be achieved.

[0038] Step 3: Secondary monitoring. Because the settlement of different areas is not uniform, after decoupling the elastic strip from the anchor head, the elastic strip is slowly passed through the channel by pulling the linear object. When the elastic strip passes the bending position of the elastic tube caused by the settlement of the stratum, the bending direction of the strain gauges on the upper and lower sides is not uniform. The bending direction is identified by the change of electrical signal of the strain gauges on the upper and lower sides, thereby realizing the monitoring of the settlement consistency of sensitive structures on the upper side of the shield tunnel.

[0039] Compared with the prior art, the beneficial effects of the present invention are:

[0040] 1. The ground micro-monitoring system during shield tunnel construction, compared with the prior art, can realize the overall monitoring of sensitive structures, avoiding local monitoring achieved through multi-point drilling, and making the monitoring values ​​more representative. When the ground settles, the elastic tube that can undergo elastic deformation will randomly bend continuously following the settlement. The linear object inside the elastic tube will pull the linear object outside the transverse borehole into the elastic tube. By obtaining the amount of traction of the linear object, the overall monitoring of the settlement in the shield area can be realized.

[0041] 2. The ground micro-monitoring system during the shield tunnel construction process, because the settlement of different areas is not uniform, decouples the elastic strip from the anchor head. By pulling the linear object, the elastic strip is slowly passed through the channel. When the elastic strip passes the bending position of the elastic tube caused by the ground settlement, the bending direction of the strain gauges on the upper and lower sides is inconsistent. The bending direction is identified by the change of electrical signal of the strain gauges on the upper and lower sides, thereby realizing the monitoring of the settlement consistency of sensitive structures on the upper side of the shield tunnel. Attached Figure Description

[0042] Figure 1 This is a schematic diagram illustrating the pre-drilling process between a pre-designed shield tunnel and a sensitive structure, as per the present invention.

[0043] Figure 2 This is a schematic diagram of the structure arranged inside the borehole after drilling according to the present invention;

[0044] Figure 3 This is a schematic diagram showing the bending of the borehole in this invention when ground subsidence occurs.

[0045] Figure 4 This is a schematic cross-sectional view of the elastic tube of the present invention;

[0046] Figure 5 This is a schematic diagram of the external structure of the support frame of the present invention;

[0047] Figure 6 This is a schematic diagram of the internal cross-sectional view of the anchor head of the present invention;

[0048] Figure 7 For the present invention Figure 6 A schematic diagram of the structure at point A;

[0049] Figure 8 For the present invention Figure 6 A schematic diagram of the structure at point B;

[0050] Figure 9 This is a schematic diagram of the external structure of the elastic strip of the present invention;

[0051] Figure 10 This is a schematic diagram of the internal cross-sectional structure of the elastic strip of the present invention;

[0052] Figure 11 This is a schematic diagram of the external structure of the hexagonal prism of the present invention.

[0053] In the diagram: 1. Soil and rock mass; 2. Shield tunnel; 3. Sensitive structure; 4. Drill rod; 5. Sleeve conveyor; 51. Drive disc; 6. Wire; 7. Support frame; 8. Reel; 9. Elastic tube; 10. Anchor head; 11. Elastic strip; 12. Battery; 13. Anchoring structure; 14. Electric push rod; 15. Limiting post; 16. Inner cavity; 17. Controller; 18. Lateral borehole; 19. Backfill material; 20. Sleeve;

[0054] 91. Outer friction layer; 92. Elastic support ring; 93. Inner sliding layer; 94. Channel;

[0055] 111. Guide surface; 112. Limiting hole; 113. Strain gauge; 114. Communication module;

[0056] 131. Motor; 132. Hexagonal column; 133. Spiral drill bit; 134. Internal spiral component;

[0057] The arrow pointing to the x-axis points upwards. Detailed Implementation

[0058] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0059] Example 1, please refer to Figures 1-7 and Figure 11 The present invention provides a technical solution:

[0060] The ground micro-monitoring system during shield tunnel construction includes a transverse borehole 18, which is located between the shield tunnel 2 and the sensitive structure 3, and is located directly above the shield tunnel 2.

[0061] The inner side of the transverse borehole 18 is backfilled with backfill material 19, and an elastic tube 9 is installed on the inner side of the backfill material 19. An anchor head 10 is provided at the end of the transverse borehole 18. The elastic tube 9 is fixedly connected to the anchor head 10. A linear object 6 is slidably connected to the inner side of the elastic tube 9. The end of the linear object 6 near the anchor head 10 can be fixed.

[0062] In this invention, a transverse borehole 18 is first created using a drill rod 4. The transverse borehole 18 is temporarily supported by a sleeve 20. The sleeve 20 is located outside the drill rod 4, with the drill rod 4 in front. The sleeve 20 and the drill rod 4 advance simultaneously, thus providing timely support for the transverse borehole 18. The rotation and advancement methods of the drill rod 4 are existing technologies and will not be elaborated upon here.

[0063] The sleeve 20 is moved forward and backward by the sleeve conveyor 5. The sleeve conveyor 5 is equipped with a rotatable drive disk 51. The drive disk 51 is in close contact with the sleeve 20. The drive disk 51 is driven to rotate by a motor, and the drive disk 51 drives the sleeve 20 to move forward and backward.

[0064] Then the anchor head 10 is passed through the sleeve 20 and pushed to the end of the transverse borehole 18. Finally, backfill material is filled into the inner side of the transverse borehole 18 through the pipe in a way from deep to shallow. The sleeve 20 is continuously withdrawn while filling. The pipe can be a flexible auger conveying pipe.

[0065] Compared with the prior art, this invention can achieve overall monitoring of sensitive building 3, avoiding local monitoring achieved through multi-point drilling, and making the monitoring values ​​more representative.

[0066] When the stratum settles, the elastic tube 9, which can undergo elastic deformation, will randomly bend continuously following the settlement. The linear object 6 inside the elastic tube 9 will pull the linear object 6 outside the transverse borehole 18 into the elastic tube 9. By obtaining the amount of traction of the linear object 6, the overall monitoring of the settlement in the shield tunnel area can be achieved. The linear object 6 can be a pull rope or a thin steel wire rope.

[0067] The elastic tube 9 has an elliptical cross-section and is wider on the upper side, allowing for a larger stress-bearing surface to settle along with the soil and rock mass 1.

[0068] Specifically, the elastic tube 9 consists of an outer friction layer 91, an elastic support ring 92, an inner sliding layer 93, and a channel 94 from the outside to the inside, with the linear object 6 disposed inside the channel 94;

[0069] The outer friction layer 91 is used to increase the friction between the tube and the soil, ensuring that the elastic tube 9 follows the movement of the surrounding soil.

[0070] The elastic support ring 92 is used to protect the presence of channel 94;

[0071] The channel 94 is coated with lubricating oil to reduce the sliding friction of the linear object 6.

[0072] Specifically, the formation micro-monitoring system also includes a support frame 7. The top of the support frame 7 is rotatably connected to a reel 8 via a rotating shaft. The rotation of the reel 8 is damped by a small force, which is only to prevent the wire 6 from becoming loose. The other end of the wire 6 is wound around the outside of the reel 8. The rotation of the reel 8 provides the traction of the wire 6. A rotation sensor is installed at the rotating shaft of the reel 8 to obtain the traction length of the wire 6.

[0073] In this invention, the rotation sensor can obtain the number of rotations and rotation angle of the reel 8, and thus calculate the traction length of the linear object 6 by multiplying the number of rotations by the circumference.

[0074] Specifically, the backfill material 19 is backfill soil or backfill mortar, which serves to support the rock and soil mass 1 and to wrap the elastic tube 9.

[0075] After backfill material 19 is filled, sleeve 20 needs to be removed so that elastic tube 9 settles along with the surrounding soil.

[0076] Specifically, the main material of the elastic tube 9 is latex, which can be stretched and bent in response to the settlement of the soil and rock mass 1.

[0077] Specifically, a battery 12 and a controller 17 are fixedly connected to the inner side of the anchor head 10. An anchoring structure 13 is provided at the anchor head 10. When the anchor head 10 undergoes horizontal displacement, it will interfere with the traction of the linear object 6. The anchoring structure 13 in this invention is used to reduce the horizontal displacement of the anchor head 10 and increase the accuracy of monitoring.

[0078] Since soil is not a good medium for wireless transmission, in this invention, the motor 131 is controlled by a wired communication module 114 and a controller 17.

[0079] Specifically, the anchoring structure 13 includes a motor 131 and an inner spiral component 134. The inner spiral component 134 is fixedly connected to the inner side of the anchor head 10. A spiral drill bit 133 is spirally connected to the inner side of the inner spiral component 134. The motor 131 is fixed to the inner side of the anchor head 10. A hexagonal column 132 is fixedly connected to the end of the main shaft of the motor 131. The outer side of the hexagonal column 132 is slidably connected to the inner side of the spiral drill bit 133. When the hexagonal column 132 rotates, the spiral drill bit 133 can rotate and screw into the inner side of the rock and soil mass 1.

[0080] In this invention, because the outer side of the hexagonal prism 132 is slidably connected to the inner side of the auger drill bit 133, when the hexagonal prism 132 rotates, it will drive the auger drill bit 133 to rotate. When the auger drill bit 133 rotates, it will rise under the action of the inner auger 134, thereby entering the inner side of the rock and soil body 1. The rotational entry method makes it easier to enter.

[0081] Example 2 is a further improvement upon Example 1. Please refer to Example 1. Figures 1-11 ,

[0082] An inner cavity 16 is provided on the inner side of the anchor head 10. An elastic strip 11 is installed on the inner side of the inner cavity 16. The elastic strip 11 is made of smooth silicone. One end of the elastic strip 11 is fixedly connected to the linear object 6. A limiting hole 112 is provided on the inner side of the end of the elastic strip 11. An electric push rod 14 is fixedly connected to the inner side of the anchor head 10. A limiting post 15 is fixedly connected to the movable end of the electric push rod 14. In the initial state, the limiting post 15 is inserted into the limiting hole 112 to lock the elastic strip 11.

[0083] The elastic tube 9 and elastic strip 11 in this invention can also be installed on the lower side of the anchor head 10. The elastic strip 11 is limited by the limiting post 15. After the moving end of the electric push rod 14 rises, the limiting post 15 and the limiting hole 112 are decoupled. The elastic strip 11 is pulled out of one side of the anchor head 10 and into the inner side of the channel 94 by dragging the wire 6.

[0084] Specifically, an electrical signal line is twisted inside the linear object 6. The electrical signal line is used to realize control and electrical signal transmission. A communication module 114 is fixedly connected to the inner side of the elastic strip 11. Strain gauges 113 are attached to the inner sides of both the upper and lower ends of the elastic strip 11. Guide surfaces 111 are provided at both ends of the elastic strip 11 to facilitate its movement in the channel 94.

[0085] Pull the wire 6 to slowly pass the elastic strip 11 through the channel 94. When the elastic strip 11 passes the bending position of the elastic tube 9 caused by the ground settlement, the bending direction of the strain gauges 113 on the upper and lower sides is inconsistent. The bending direction is identified by the inconsistency of the electrical signal changes of the strain gauges 113 on the upper and lower sides, thereby realizing the whole-area settlement consistency monitoring of the sensitive structure 3 on the shield tunnel 2.

[0086] In this invention, the specific principle by which the bending direction of the elastic strip 11 is reflected through the change in electrical signals of the upper and lower strain gauges 113 is as follows:

[0087] When the elastic strip 11 bends, one surface is stretched, generating tensile strain, while the other surface is compressed, generating compressive strain. The strain magnitudes on the upper and lower surfaces are approximately equal, but their signs are opposite. The strain gauge attached to the upper surface is under tension, increasing its resistance, while the strain gauge attached to the lower surface is under compression, decreasing its resistance. By measuring the sign of the resistance change of these two strain gauges (positive or negative), it is possible to directly determine whether the elastic strip 11 bends upwards or downwards. This is existing technology and will not be elaborated further here.

[0088] This invention also discloses a method for microscopic monitoring of the strata during shield tunnel construction, the steps of which are as follows:

[0089] Step 1: Installation. A transverse borehole 18 is created using drill rod 4. The transverse borehole 18 is first temporarily supported by sleeve 20. Then, anchor head 10 is passed through sleeve 20 and pushed to the end of transverse borehole 18. Finally, backfill material is filled into the inside of transverse borehole 18 through pipe in a manner from deep to shallow. Sleeve 20 is continuously withdrawn while filling.

[0090] Step 2: During a single monitoring session, when ground subsidence occurs, the elastic tube 9, which can undergo elastic deformation, will randomly and continuously bend in accordance with the subsidence. The linear object 6 inside the elastic tube 9 will pull the linear object 6 outside the transverse borehole 18 into the elastic tube 9. By obtaining the amount of traction of the linear object 6, the overall monitoring of the shield tunnel area can be achieved.

[0091] Step 3: Secondary monitoring. Because the settlement of different areas is not consistent, after decoupling the elastic strip 11 from the anchor head 10, the elastic strip 11 is slowly passed through the channel 94 by pulling the wire 6. When the elastic strip 11 passes through the bending position of the elastic tube 9 caused by the settlement of the stratum, the bending direction of the strain gauges 113 on the upper and lower sides is inconsistent. The bending direction is identified by the change of the electrical signal of the strain gauges 113 on the upper and lower sides, thereby realizing the monitoring of the settlement consistency of the sensitive structure 3 on the upper side of the shield tunnel 2.

[0092] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A ground micro-monitoring system during shield tunnel construction, including a transverse borehole (18), characterized in that: The transverse borehole (18) is located between the shield tunnel (2) and the sensitive structure (3), and is located directly above the shield tunnel (2); The inner side of the transverse borehole (18) is backfilled with backfill material (19), and an elastic tube (9) is installed on the inner side of the backfill material (19). An anchor head (10) is provided at the end of the transverse borehole (18). The elastic tube (9) is fixedly connected to the anchor head (10). A wire (6) is slidably connected to the inner side of the elastic tube (9). The end of the wire (6) near the anchor head (10) can be fixed. When the strata settle, the elastic tube (9) that can undergo elastic deformation will randomly bend continuously following the settlement. The linear object (6) inside the elastic tube (9) will pull the linear object (6) outside the transverse borehole (18) into the elastic tube (9). By obtaining the amount of traction of the linear object (6), the overall monitoring of the settlement in the shield tunnel area can be achieved.

2. The ground micro-monitoring system during shield tunnel construction according to claim 1, characterized in that: The elastic tube (9) consists of an outer friction layer (91), an elastic support ring (92), an inner sliding layer (93), and a channel (94) from the outside to the inside. A linear object (6) is placed inside the channel (94). The outer friction layer (91) is used to increase the friction between the tube and the soil, ensuring that the elastic tube (9) moves with the surrounding soil. The elastic support ring (92) is used to protect the presence of the channel (94); The channel (94) is coated with lubricating oil to reduce the sliding friction of the filament (6).

3. The ground micro-monitoring system during shield tunnel construction according to claim 1, characterized in that: The formation micro-monitoring system also includes a support frame (7), the top of which is rotatably connected to a reel (8) via a rotating shaft. The rotation of the reel (8) is damped. The other end of the wire (6) is wound around the outside of the reel (8). The rotation of the reel (8) provides the traction of the wire (6). A rotation sensor is provided at the rotating shaft of the reel (8) to obtain the traction length of the wire (6).

4. The ground micro-monitoring system during shield tunnel construction according to claim 1, characterized in that: The backfill material (19) is backfill soil or backfill mortar, which serves to support the rock and soil mass (1) and wrap the elastic tube (9).

5. The ground micro-monitoring system during shield tunnel construction according to claim 1, characterized in that: The main material of the elastic tube (9) is latex, which can be stretched and bent with the settlement of the rock and soil (1).

6. The ground micro-monitoring system during shield tunnel construction according to any one of claims 1-5, characterized in that: A battery (12) and a controller (17) are fixedly connected to the inside of the anchor head (10). An anchoring structure (13) is provided at the anchor head (10). The anchoring structure (13) is used to reduce the horizontal displacement of the anchor head (10) and increase the accuracy of monitoring.

7. The ground micro-monitoring system during shield tunnel construction according to claim 6, characterized in that: The anchoring structure (13) includes a motor (131) and an inner spiral component (134). The inner spiral component (134) is fixedly connected to the inner side of the anchor head (10). The inner side of the inner spiral component (134) is spirally connected to a spiral drill bit (133). The motor (131) is fixed to the inner side of the anchor head (10). The end of the main shaft of the motor (131) is fixedly connected to a hexagonal column (132). The outer side of the hexagonal column (132) is slidably connected to the inner side of the spiral drill bit (133). When the hexagonal column (132) rotates, the spiral drill bit (133) can rotate and screw into the inner side of the rock and soil mass (1).

8. The ground micro-monitoring system during shield tunnel construction according to any one of claims 1-5, characterized in that: The anchor head (10) has an inner cavity (16) on its inner side. An elastic strip (11) is installed on the inner side of the inner cavity (16). The elastic strip (11) is made of smooth silicone. One end of the elastic strip (11) is fixedly connected to the linear object (6). A limiting hole (112) is opened on the inner side of the end of the elastic strip (11). An electric push rod (14) is fixedly connected to the inner side of the anchor head (10). The movable end of the electric push rod (14) is fixedly connected to a limiting post (15). In the initial state, the limiting post (15) is inserted into the limiting hole (112) to lock the elastic strip (11).

9. The ground micro-monitoring system during shield tunnel construction according to claim 8, characterized in that: The linear object (6) contains an electrical signal line, and the inner side of the elastic strip (11) is fixedly connected to a communication module (114). Strain gauges (113) are attached to the inner sides of both the upper and lower ends of the elastic strip (11). The two ends of the elastic strip (11) are provided with guide surfaces (111) to facilitate movement within the channel (94). Pull the wire (6) to make the elastic strip (11) slowly pass through the channel (94). When the elastic strip (11) passes through the bending position of the elastic tube (9) caused by the settlement of the stratum, the bending direction of the upper and lower strain gauges (113) is inconsistent. The bending direction is identified by the inconsistency of the electrical signal changes of the upper and lower strain gauges (113), thereby realizing the whole-area settlement consistency monitoring of the sensitive structure (3) on the shield tunnel (2).

10. A method for microscopic monitoring of strata during shield tunnel construction, using the strata microscopic monitoring system as described in claim 9, characterized in that: The steps are as follows: Step 1: Installation. A transverse borehole (18) is created using a drill rod (4). The transverse borehole (18) is first temporarily supported by a sleeve (20). Then, the anchor head (10) is passed through the sleeve (20) and pushed to the end of the transverse borehole (18). Finally, backfill material is filled into the inner side of the transverse borehole (18) through a pipe in a manner from deep to shallow. The sleeve (20) is continuously withdrawn while filling. Step 2: During a single monitoring session, when the stratum settles, the elastic tube (9), which can undergo elastic deformation, will randomly bend continuously following the settlement. The linear object (6) inside the elastic tube (9) will pull the linear object (6) outside the transverse borehole (18) into the elastic tube (9). By obtaining the amount of traction of the linear object (6), the overall monitoring of the shield tunnel area can be achieved. Step 3: Secondary monitoring. Because the settlement of each area is not consistent, after decoupling the elastic strip (11) from the anchor head (10), the elastic strip (11) is slowly passed through the channel (94) by pulling the wire (6). When the elastic strip (11) passes through the bending position of the elastic tube (9) caused by the settlement of the stratum, the bending direction of the upper and lower strain gauges (113) is inconsistent. The bending direction is identified by the change of electrical signal of the upper and lower strain gauges (113), thereby realizing the monitoring of the settlement consistency of the sensitive structure (3) on the shield tunnel (2).

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