Construction method for double-shield TBM to penetrate through fractured rock mass and grouting mechanism

Abstract

The invention relates to the technical field of TBM (tunnel boring machine) broken rock mass crossing, in particular to a double-shield TBM broken rock mass crossing construction method and a grouting mechanism. The construction method comprises the following steps: S1, advanced detection; s2, advanced reinforcement; s3, forming a waterproof curtain; s4, drilling is conducted; by means of the construction method, the rock mass in front of the TBM can be stabilized, and the machine blocking risk caused by unstable geological conditions in the tunneling process of the TBM is reduced; the grouting mechanism comprises a grouting machine and a grouting pipe assembly, the grouting pipe assembly comprises an outer pipe and an inner pipe, a first grouting hole is formed in the side wall of the outer pipe, and a second grouting hole is formed in the side wall of the inner pipe; a first limiting groove is formed in the inner side wall of the outer pipe, and a second limiting groove is formed in the outer side wall of the inner pipe; a rubber pad extending into the second limiting groove is arranged in the first limiting groove; when the grouting pipe assembly is inserted into the grouting hole, soil or small stones can be prevented from entering the inner pipe through the first grouting hole and the second grouting hole to block the inner pipe, and grouting is not affected.

Description

Technical Field

[0001] The invention relates to the technical field of TBM passing through broken rock mass, and in particular to a construction method and a grouting mechanism for a double-shield TBM passing through broken rock mass. Background Art

[0002] TBM mainly includes key components such as cutter head, main drive, shield, main beam, etc. TBM is a special tunnel excavation equipment, mainly used for tunnel construction in hard rock formations; however, fault fracture zones often appear in hard rock formations; the rock mass in the fault fracture zone area has more cracks, and is severely broken and weathered, which reduces the strength and stability of the foundation rock mass. When the TBM passes through the fault fracture zone, it is easy to get stuck due to the large amount of gravel in the fault fracture zone, and the surrounding rock in the fault fracture zone is prone to collapse. For the shield TBM, the probability of getting stuck is higher under the conditions of surrounding rock collapse, convergence and deformation, and the difficulty of getting out is greater. Summary of the invention

[0003] The present invention provides a construction method and a grouting mechanism for a double-shield TBM to penetrate a broken rock mass, which can overcome certain or some defects of the prior art.

[0004] According to a double shield TBM construction method for passing through broken rock mass of the present invention, the steps are as follows: S1. Advance detection Use the rock-breaking source seismic wave detection device in the TBM to detect the geological conditions 50-100 meters ahead of the TBM during the TBM excavation process, and stop the TBM excavation when the fault fracture zone is found; S2. Advanced reinforcement After the TBM stops excavating, the front of the tunnel face is reinforced by grouting through the grouting mechanism, and the reinforcement depth is 10-20 meters; the grouting mechanism includes a grouting machine and a grouting pipe assembly, and the grouting pipe assembly is divided into an outer pipe and an inner pipe; the outer wall of the outer pipe and the inner pipe are respectively provided with multiple first grouting holes and second grouting holes; the construction personnel drill multiple grouting holes at the tunnel face, and then insert the outer pipe and the inner pipe into the grouting holes respectively, and finally rotate the inner pipe so that the second grouting hole on the inner pipe is aligned with the first grouting hole on the outer pipe, and then connect the outer pipe and the inner pipe to the grouting machine, and complete the grouting through the grouting machine to reinforce the tunnel face; S3, forming a water-blocking curtain After the tunnel face reinforcement is completed, the construction workers pass the drill rod of the drilling machine through the through hole on the TBM shield and drill grouting holes at an angle. The depth of the grouting holes extends to the front of the tunnel face. The grouting holes are drilled at intervals along the circumference of the TBM shield. Then, the grouting pipe assembly is inserted into the grouting hole, and then the grouting pipe assembly is connected to the grouting machine. The grouting is completed through the grouting machine, so that an umbrella-shaped water-blocking curtain is formed on the periphery of the TBM shield. S4, drilling After the water-blocking curtain is formed, the TBM is started and drilling begins. After drilling 10-20 meters each time, drilling is stopped and steps S2 and S3 are repeated until the TBM completely passes through the fault fracture zone.

[0005] Through the present invention, grouting reinforcement is first performed on the tunnel face and the front of the tunnel face. Grouting reinforcement can significantly improve the physical and mechanical properties of the formations in the fault fracture zone, thereby reducing the difference between the formations and ensuring the stability of the TBM during excavation. At the same time, through reinforcement treatment, the rock mass in front of the TBM can be stabilized, reducing the risk of the TBM getting stuck due to unstable geological conditions during the excavation process. Since the first purpose of ground reinforcement is to block water, through the formation of a water-blocking curtain, a curtain-like or umbrella-shaped protective cover is formed in the TBM excavation work area to prevent excessive water from flowing into the cave. At the same time, it can stabilize the weak strata, reduce the change of groundwater, and prevent possible settlement.

[0006] This method can form a dry and solid protective layer along the tunnel line outside the TBM, and form a cylindrical protective belt through grouting by the grouting mechanism, which will significantly improve the original geological characteristics: the overall strength is improved, the excavation strength is improved, the cohesion is improved, and the permeability is improved, so that the TBM can pass through the fault fracture zone smoothly.

[0007] Through the present invention, during the drilling process of the TBM, the propulsion speed starts at 20%. After the surrounding rock change trend stabilizes, the propulsion speed can be increased by 45%, and the torque change range is less than 10%.

[0008] Through the present invention, the TBM advancement speed is initially set to 20%, at which time the TBM drilling speed is relatively slow, which is used to observe the changing trend of the surrounding rock in the early stage of construction; by advancing at a relatively slow speed, various parameters in the construction process can be better controlled and adjusted in time to adapt to the changes in the surrounding rock; After the surrounding rock change trend stabilizes, the advancement speed can be increased to about 45%; this means that after confirming that the surrounding rock properties are stable and there are no major geological changes or risks, the advancement speed can be appropriately increased to improve construction efficiency; A torque variation range of less than 10% is an important control indicator; torque is one of the key parameters in the TBM construction process, which reflects the cutting force and propulsion force of the tunnel boring machine on the surrounding rock; controlling the torque variation range within 10% can ensure stability and consistency during the construction process and reduce construction problems or risks caused by torque fluctuations.

[0009] Preferably, when 15%-25% of blocky slag appears on the TBM conveyor belt during TBM drilling, the advancement speed is reduced and the penetration is controlled to be less than 6m; when blocky slag appears continuously on the conveyor belt, the cutter head speed is lowered and the penetration is reduced.

[0010] Through the present invention, when a certain proportion of blocky slag appears on the belt conveyor, it usually means that there may be larger stones or hard interlayers in the surrounding rock; in order to avoid excessive impact and wear on the tunnel boring machine and ensure the stability of the construction, the advancement speed should be reduced; at the same time, the penetration is controlled to be no more than 6m, which can reduce the disturbance of the tunnel boring machine to the surrounding rock and avoid causing instability of the surrounding rock; When a large amount of blocky slag appears continuously on the conveyor belt, it means that the surrounding rock conditions may have changed significantly, or the tunnel boring machine has encountered a particularly hard rock formation. In this case, simply reducing the advancement speed may not be enough to meet the construction challenges. Therefore, it is necessary to reduce the cutter head speed to reduce the cutting force and impact on the surrounding rock. At the same time, the penetration rate is further reduced to better control the excavation process and protect the tunnel boring machine from damage.

[0011] Preferably, during grouting, resin double-liquid grouting is used.

[0012] Through the present invention, the resin double-liquid grouting can effectively seal cracks, consolidate loose strata into a whole, isolate water sources, block water points, reduce water gushing, improve construction conditions, and achieve the purpose of water stopping and reinforcement; the resin double-liquid grouting has a short initial setting time and strong resistance to water dilution, and can quickly form a consolidated body with a certain strength, providing a stable working environment for TBM excavation.

[0013] Preferably, when the TBM is drilling and the TBM cutterhead or shield is stuck, firstly, a hand-held pneumatic drill is used to drill holes or a pneumatic pick is used to jack up holes on the face to reinforce the loose surrounding rock by grouting. Then, the advance drill or multi-functional drill configured on the TBM is used to perform pre-grouting treatment to reinforce the loose surrounding rock in front of the shield and the face. Finally, excavation is carried out forward and backward at the two waistlines of the TBM, excavation is carried out from the bottom of both sides to the front, and excavation is carried out from above the shield to dig out pilot holes respectively. Finally, the TBM is started for secondary drilling.

[0014] The present invention can quickly release the TBM cutter head jam or shield jam when the TBM is stuck, thereby accelerating the construction speed.

[0015] The present invention provides a grouting mechanism, which comprises a grouting machine and a grouting pipe assembly, wherein the grouting pipe assembly comprises an outer pipe and an inner pipe, wherein a plurality of first grouting holes arranged at intervals along the length direction of the outer pipe are arranged on the side wall of the outer pipe, and the plurality of first grouting holes are distributed circumferentially along the outer pipe; a second grouting hole arranged corresponding to the first grouting hole is arranged on the side wall of the inner pipe; a first limiting groove arranged along the length direction of the outer pipe is arranged on the inner side wall of the outer pipe, and a second limiting groove arranged corresponding to the first limiting groove is arranged on the outer side wall of the inner pipe; a rubber pad extending into the second limiting groove is arranged in the first limiting groove.

[0016] According to the present invention, during the process of inserting the grouting pipe assembly into the grouting hole, before the grouting pipe assembly is inserted, the construction personnel first rotate the inner pipe to displace the second grouting hole on the inner pipe with the first grouting hole on the outer pipe, thereby blocking the first grouting hole on the outer pipe through the inner pipe. At this time, during the process of inserting the grouting pipe assembly into the grouting hole, the first grouting hole is blocked, thereby preventing the grouting pipe assembly from being inserted into the grouting hole and being blocked by soil or fine stones through the first grouting hole and the second grouting hole into the inner pipe to affect grouting. After the grouting pipe assembly is fully extended into the grouting hole, the construction personnel rotate the inner pipe to connect the second grouting hole on the inner pipe with the first grouting hole on the outer pipe, and then grouting is performed on the inner pipe by a grouting machine.

[0017] Preferably, a conical head is provided at one end of the outer tube, and a collar is provided at the other end; a plurality of connecting plates for connecting the collar and the outer tube are provided between the collar and the outer tube; the position of the connecting plates corresponds to the position of the first limiting groove.

[0018] By means of the present invention, when the outer tube is extended into the grouting hole, the cone head can be more easily inserted into the rock or soil, thereby fixing the outer tube.

[0019] Preferably, one end of the inner tube close to the collar extends out of the outer tube, and the side wall of the end of the inner tube extending out of the outer tube expands outward to form a rotating block in a rectangular shape; the corners of the rotating block correspond to the connecting plate.

[0020] With the present invention, construction workers can use a wrench to twist the rotating block, and the rotation of the rotating block drives the inner tube to rotate; thus, it is convenient for construction workers to rotate the inner tube; in the process of rotating the inner tube, since the corners of the rotating block correspond to the connecting plate, and the position of the connecting plate corresponds to the position of the first limiting groove, when the construction workers rotate the inner tube, it is convenient for the construction workers to know whether the first grouting hole is connected with the second grouting hole, and whether the rubber pad in the first limiting groove extends into the second limiting groove to fix the inner tube.

[0021] Preferably, the opening width of the first limiting groove is smaller than the bottom width of the first limiting groove.

[0022] Through the present invention, the opening of the first limiting groove can block the rubber pad, thereby preventing the rubber pad from being separated from the first limiting groove.

[0023] Preferably, both the outer tube and the inner tube are made of stainless steel.

[0024] Through the present invention, the stainless steel structure has a relatively high strength, and the service life of the outer tube and the inner tube can be prolonged. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of the grouting pipe assembly in Example 1.

[0026] Figure 2 This is an enlarged view of the tail of the grouting pipe assembly in Example 1.

[0027] Figure 3 Schematic diagram of the outer tube and the inner tube in Example 1.

[0028] Figure 4 This is a schematic cross-sectional view of the grouting pipe assembly in Example 1.

[0029] Figure 5 Schematic diagram of the inner tube in Example 1.

[0030] Figure 6 Schematic diagram of the outer tube in Example 1. DETAILED DESCRIPTION

[0031] In order to further understand the content of the present invention, the present invention is described in detail in conjunction with the embodiments. It should be understood that the embodiments are only for explaining the present invention and are not intended to limit it.

[0032] Example 1 This embodiment provides a double shield TBM construction method for passing through broken rock mass, the steps are as follows: S1. Advance detection Use the rock-breaking source seismic wave detection device in the TBM to detect the geological conditions 50-100 meters ahead of the TBM during the TBM excavation process, and stop the TBM excavation when the fault fracture zone is found; S2. Advanced reinforcement After the TBM stops excavating, the front of the tunnel face is reinforced by grouting through a grouting mechanism, and the reinforcement depth is 10-20 meters; the grouting mechanism includes a grouting machine and a grouting pipe assembly 100, and the grouting pipe assembly 100 is divided into an outer pipe 130 and an inner pipe 310; the outer side walls of the outer pipe 130 and the inner pipe 310 are respectively provided with a plurality of first grouting holes 120 and a second grouting hole 320; the construction personnel drill a plurality of grouting holes at the tunnel face, and then insert the outer pipe 130 and the inner pipe 310 into the grouting holes respectively, and finally rotate the inner pipe 310 to align the second grouting hole 320 on the inner pipe 310 with the first grouting hole 120 on the outer pipe 130, and then connect the outer pipe 130 and the inner pipe 310 to the grouting machine, and complete the grouting through the grouting machine to reinforce the tunnel face; S3, forming a water-blocking curtain After the tunnel face reinforcement is completed, the construction personnel pass the drill rod of the drilling machine through the through hole on the TBM shield, and drill grouting holes at an angle, the depth of which extends to the front of the tunnel face; and the grouting holes are drilled at intervals along the circumference of the TBM shield; then the grouting pipe assembly 100 is inserted into the grouting hole, and then the grouting pipe assembly 100 is connected to the grouting machine, and the grouting is completed by the grouting machine, so that an umbrella-shaped water-blocking curtain is formed on the periphery of the TBM shield; S4, drilling After the water-blocking curtain is formed, the TBM is started and drilling begins. After drilling 10-20 meters each time, drilling is stopped and steps S2 and S3 are repeated until the TBM completely passes through the fault fracture zone.

[0033] Through this embodiment, grouting reinforcement is first performed on the tunnel face and the front of the tunnel face. Grouting reinforcement can significantly improve the physical and mechanical properties of the formations in the fault fracture zone, thereby reducing the difference between the formations and ensuring the stability of the TBM during excavation. At the same time, through reinforcement treatment, the rock mass in front of the TBM can be stabilized, reducing the risk of the TBM getting stuck due to unstable geological conditions during the excavation process. Since the first purpose of ground reinforcement is to block water, through the formation of a water-blocking curtain, a curtain-like or umbrella-shaped protective cover is formed in the TBM excavation work area to prevent excessive water from flowing into the cave. At the same time, it can stabilize the weak strata, reduce the change of groundwater, and prevent possible settlement.

[0034] This method can form a dry and solid protective layer along the tunnel line outside the TBM, and form a cylindrical protective belt through grouting by the grouting mechanism, which will significantly improve the original geological characteristics: the overall strength is improved, the excavation strength is improved, the cohesion is improved, and the permeability is improved, so that the TBM can pass through the fault fracture zone smoothly.

[0035] Through this embodiment, during the drilling process of the TBM, the propulsion speed starts at 20%. After the surrounding rock change trend stabilizes, the propulsion speed can be increased by 45%, and the torque change range is less than 10%.

[0036] In this embodiment, the TBM advancement speed is initially set to 20%, at which time the TBM drilling speed is relatively slow, which is used to observe the changing trend of the surrounding rock in the early stage of construction; by advancing at a relatively slow speed, various parameters in the construction process can be better controlled and adjusted in time to adapt to the changes in the surrounding rock; After the surrounding rock change trend stabilizes, the advancement speed can be increased to about 45%; this means that after confirming that the surrounding rock properties are stable and there are no major geological changes or risks, the advancement speed can be appropriately increased to improve construction efficiency; A torque variation range of less than 10% is an important control indicator; torque is one of the key parameters in the TBM construction process, which reflects the cutting force and propulsion force of the tunnel boring machine on the surrounding rock; controlling the torque variation range within 10% can ensure stability and consistency during the construction process and reduce construction problems or risks caused by torque fluctuations.

[0037] In this embodiment, when the TBM is drilling, if 15%-25% of blocky slag appears on the belt conveyor of the TBM, the advancement speed is reduced and the penetration is controlled to be less than 6m; when blocky slag appears continuously on the belt conveyor, the cutter head speed is lowered and the penetration is reduced.

[0038] Through this embodiment, when a certain proportion of blocky slag appears on the belt conveyor, it usually means that there may be larger stones or hard interlayers in the surrounding rock; in order to avoid excessive impact and wear on the tunnel boring machine and ensure the stability of the construction, the advancement speed should be reduced; at the same time, the penetration is controlled to be no more than 6m, which can reduce the disturbance of the tunnel boring machine to the surrounding rock and avoid causing instability of the surrounding rock; When a large amount of blocky slag appears continuously on the conveyor belt, it means that the surrounding rock conditions may have changed significantly, or the tunnel boring machine has encountered a particularly hard rock formation. In this case, simply reducing the advancement speed may not be enough to meet the construction challenges. Therefore, it is necessary to reduce the cutter head speed to reduce the cutting force and impact on the surrounding rock. At the same time, the penetration rate is further reduced to better control the excavation process and protect the tunnel boring machine from damage.

[0039] In this embodiment, the grouting liquid used during grouting is resin double liquid grouting.

[0040] Through this embodiment, the resin double-liquid grouting can effectively seal cracks, consolidate loose strata into a whole, isolate water sources, block water points, reduce water gushing, improve construction conditions, and achieve the purpose of water stopping and reinforcement; the resin double-liquid grouting has a short initial setting time and strong resistance to water dilution, and can quickly form a consolidated body with a certain strength, providing a stable working environment for TBM excavation.

[0041] In this embodiment, when the TBM is drilling and the TBM cutterhead or shield is stuck, first, a hand pneumatic drill is used to drill holes or a pneumatic pick is used to jack up the face to grout the face to reinforce the loose surrounding rock; then, the advance drill or multi-functional drill configured on the TBM is used to perform pre-grouting treatment to reinforce the loose surrounding rock in front of the shield and the face; finally, excavation is carried out forward and backward at the two waistlines of the TBM, excavation is carried out from the bottom of both sides to the front, and excavation is carried out from above the shield to dig out pilot holes respectively; finally, the TBM is started for secondary drilling.

[0042] Through this embodiment, when the TBM is stuck, the TBM cutter head or shield jam can be quickly released, thereby speeding up the construction.

[0043] The present embodiment provides a grouting mechanism, which includes a grouting machine and a grouting pipe assembly 100. The grouting pipe assembly 100 includes an outer pipe 130 and an inner pipe 310. The outer pipe 130 is provided with a plurality of first grouting holes 120 spaced apart along the length direction of the outer pipe 130 on the side wall, and the plurality of first grouting holes 120 are distributed circumferentially along the outer pipe 130; the inner pipe 310 is provided with a second grouting hole 320 corresponding to the first grouting hole 120 on the side wall; the outer pipe 130 is provided with a first limiting groove 410 along the length direction of the outer pipe 130 on the inner side wall, and the inner pipe 310 is provided with a second limiting groove 430 corresponding to the first limiting groove 410 on the outer side wall; a rubber pad 420 extending into the second limiting groove 430 is provided in the first limiting groove 410.

[0044] Through this embodiment, when the construction personnel insert the grouting pipe assembly 100 into the grouting hole, before the grouting pipe assembly 100 is inserted, the construction personnel first rotate the inner pipe 310 to displace the second grouting hole 320 on the inner pipe 310 with the first grouting hole 120 on the outer pipe 130, so that the first grouting hole 120 on the outer pipe 130 is blocked by the inner pipe 310. At this time, when the grouting pipe assembly 100 is inserted into the grouting hole, the first grouting hole 120 is blocked, thereby preventing the grouting pipe assembly 100 from being inserted into the grouting hole. The grouting is blocked by soil or fine stones through the first grouting hole 120 and the second grouting hole 320. After the grouting pipe assembly 100 is fully extended into the grouting hole, the construction personnel rotate the inner pipe 310 to connect the second grouting hole 320 on the inner pipe 310 with the first grouting hole 120 on the outer pipe 130, and then grouting is performed on the inner pipe 310 by a grouting machine.

[0045] In this embodiment, a cone-shaped cone head 110 is provided at one end of the outer tube 130, and a ring 230 is provided at the other end; a plurality of connecting plates 220 for connecting the ring 230 and the outer tube 130 are provided between the ring 230 and the outer tube 130; the position of the connecting plate 220 corresponds to the position of the first limiting groove 410.

[0046] According to this embodiment, when the outer tube 130 is extended into the grouting hole, the cone head 110 can be more easily inserted into the rock or soil, thereby fixing the outer tube 130 .

[0047] In this embodiment, one end of the inner tube 310 close to the collar 230 extends out of the outer tube 130 , and the side wall of the end of the inner tube 310 extending out of the outer tube 130 expands outward to form a rectangular rotating block 210 ; the corners of the rotating block 210 correspond to the connecting plate 220 .

[0048] Through this embodiment, the construction personnel can use a wrench to turn the rotating block 210, and the rotation of the rotating block 210 drives the inner tube 310 to rotate; thereby, it is convenient for the construction personnel to rotate the inner tube 310; in the process of rotating the inner tube 310, since the corners of the rotating block 210 correspond to the connecting plate 220, and the position of the connecting plate 220 corresponds to the position of the first limiting groove 410, when the construction personnel rotate the inner tube 310, it is convenient for the construction personnel to know whether the first grouting hole 120 is connected with the second grouting hole 320, and whether the rubber pad 420 in the first limiting groove 410 extends into the second limiting groove 430 to fix the inner tube 310.

[0049] In this embodiment, the opening width of the first limiting groove 410 is smaller than the bottom width of the first limiting groove 410 .

[0050] Through this embodiment, the opening of the first limiting groove 410 can block the rubber pad 420 to prevent the rubber pad 420 from being separated from the first limiting groove 410 .

[0051] In this embodiment, the outer tube 130 and the inner tube 310 are both made of stainless steel.

[0052] Through this embodiment, the stainless steel structure has a strong strength, which can extend the service life of the outer tube 130 and the inner tube 310.

[0053] It is easy to understand that those skilled in the art can combine, split, reorganize, etc. the embodiments of the present application to obtain other embodiments based on one or several embodiments provided in the present application, and these embodiments do not exceed the protection scope of the present application.

[0054] The present invention and its implementation methods are described schematically above, and the description is not restrictive. The embodiments shown in the embodiments are only part of the implementation methods of the present invention, and the actual structure is not limited thereto. Therefore, if a person skilled in the art is inspired by the embodiments and designs a structure and an implementation method similar to the technical solution without creativity without departing from the purpose of the invention, they should all fall within the protection scope of the present invention.

Claims

1. A double shield TBM construction method for crossing broken rock mass, the steps are as follows: S1. Advance detection Use the rock-breaking source seismic wave detection device in the TBM to detect the geological conditions 50-100 meters ahead of the TBM during the TBM excavation process, and stop the TBM excavation when the fault fracture zone is found; S2. Advanced reinforcement After the TBM stops excavating, grouting is performed in front of the tunnel face through a grouting mechanism, and the reinforcement depth is 10-20 meters. The grouting mechanism includes a grouting machine and a grouting pipe assembly (100), and the grouting pipe assembly (100) is divided into an outer pipe (130) and an inner pipe (310). The outer side walls of the outer pipe (130) and the inner pipe (310) are respectively provided with a plurality of first grouting holes (120) and a second grouting hole (320). Construction personnel drill a plurality of grouting holes at the tunnel face, and then insert the outer pipe (130) and the inner pipe (310) into the grouting holes respectively, and finally rotate the inner pipe (310) so that the second grouting hole (320) on the inner pipe (310) is aligned with the first grouting hole (120) on the outer pipe (130), and then connect the outer pipe (130) and the inner pipe (310) to the grouting machine, and complete grouting through the grouting machine to reinforce the tunnel face. S3, forming a water-blocking curtain After the tunnel face reinforcement is completed, the construction personnel pass the drill rod of the drilling machine through the through hole on the TBM shield, and drill grouting holes at an angle, the depth of the grouting holes extending to the front of the tunnel face; and the grouting holes are drilled at intervals along the circumference of the TBM shield; then the grouting pipe assembly (100) is inserted into the grouting hole, and then the grouting pipe assembly (100) is connected to the grouting machine, and grouting is completed by the grouting machine, so that an umbrella-shaped water-blocking curtain is formed on the periphery of the TBM shield; S4, drilling After the water-blocking curtain is formed, the TBM is started and drilling begins. After drilling 10-20 meters each time, drilling is stopped and steps S2 and S3 are repeated until the TBM completely passes through the fault fracture zone.

2. A double-shield TBM construction method for passing through broken rock mass according to claim 1, characterized in that: During the drilling process of TBM, the propulsion speed starts at 20%. After the surrounding rock change trend stabilizes, the propulsion speed can be increased to 45%, and the torque change range is less than 10%.

3. A double shield TBM construction method for passing through broken rock mass according to claim 2, characterized in that: When the TBM is drilling, if 15%-25% of the blocky slag appears on the TBM's conveyor belt, reduce the advancement speed and control the penetration to less than 6m; when blocky slag appears continuously on the conveyor belt, lower the cutter head speed and reduce the penetration.

4. A double-shield TBM construction method for passing through broken rock mass according to claim 1, characterized in that: During grouting, resin double liquid grouting is used.

5. A double shield TBM construction method for passing through broken rock mass according to claim 1, characterized in that: When the TBM is drilling and the TBM cutterhead or shield is stuck, first use a hand pneumatic drill to drill holes or a pneumatic pick to jack up on the face to grout the face to reinforce the loose surrounding rock; then use the advance drill or multi-functional drill configured on the TBM to perform pre-grouting to reinforce the loose surrounding rock in front of the shield and the face; finally, excavate forward and backward at the two waistlines of the TBM, excavate from the bottom of both sides to the front, and excavate from above the shield to dig out pilot holes respectively; finally, start the TBM for secondary drilling.

6. A grouting mechanism, used in steps S2 and S3 of a double shield TBM construction method for penetrating a broken rock mass, comprising a grouting machine and a grouting pipe assembly (100), characterized in that: The grouting pipe assembly (100) comprises an outer pipe (130) and an inner pipe (310); a plurality of first grouting holes (120) arranged at intervals along the length direction of the outer pipe (130) are provided on the side wall of the outer pipe (130); the plurality of first grouting holes (120) are distributed along the circumference of the outer pipe (130); a second grouting hole (320) corresponding to the first grouting holes (120) is provided on the side wall of the inner pipe (310); a first limiting groove (410) arranged along the length direction of the outer pipe (130) is provided on the inner side wall of the outer pipe (130); a second limiting groove (430) corresponding to the first limiting groove (410) is provided on the outer side wall of the inner pipe (310); and a rubber pad (420) extending into the second limiting groove (430) is provided in the first limiting groove (410).

7. A grouting mechanism according to claim 6, characterized in that: A cone head (110) in a conical shape is provided at one end of the outer tube (130), and a collar (230) is provided at the other end; a plurality of connecting plates (220) for connecting the collar (230) and the outer tube (130) are provided between the collar (230) and the outer tube (130); the position of the connecting plate (220) corresponds to the position of the first limiting groove (410).

8. A grouting mechanism according to claim 7, characterized in that: One end of the inner tube (310) close to the collar (230) extends out of the outer tube (130), and the side wall of one end of the inner tube (310) extending out of the outer tube (130) expands outward to form a rotating block (210) in a rectangular shape; the corners of the rotating block (210) correspond to the connecting plate (220).

9. A grouting mechanism according to claim 7, characterized in that: The opening width of the first limiting groove (410) is smaller than the bottom width of the first limiting groove (410).

10. A grouting mechanism according to claim 6, characterized in that: The outer tube (130) and the inner tube (310) are both made of stainless steel.

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