A shield tail water stop device for shield tunneling and a method for implementing the same

Abstract

The application provides a shield tail water stop device for butt joint in shield tunneling, which comprises a protection steel plate, a sealing steel plate and a fastener installed along a segment ring, the protection steel plate is an annular steel plate closely attached to a segment and a ring joint sealing gasket, the sealing steel plate is an annular steel plate welded to a shield shell, the protection steel plate and the sealing steel plate are both provided with fastening holes matched with the fastener, and the fastener is used for fastening and connecting the segment, the protection steel plate and the sealing steel plate. The application also provides a shield tail water stop implementation method for butt joint in shield tunneling. The water stop device provided by the application realizes waterproof sealing between the segment and the water stop device by pressing the segment ring gasket through the protection steel plate, realizes waterproof sealing between the shield tail and the water stop device by welding the sealing steel plate to the inner side of the shield shell, and realizes waterproof sealing between the shield tail gap and the steel plate gap by grouting sealing, and other waterproof reinforcement measures, so that the water stop device is ensured not to seep and leak under high water pressure.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of shield tail water stop for shield in-situ butt joint, and particularly to a shield tail water stop device for shield in-situ butt joint and an implementation method. BACKGROUND

[0002] With the wide application of shield method in tunnel construction, the geological conditions and groundwater environment faced by the shield machine are more and more complex, the route is longer, and the system failure of the shield machine itself may cause a single shield machine to be unable to complete the tunneling task. At this time, two shield machines need to be used to excavate in opposite directions and butt joint in-situ. During the shield in-situ butt joint process, the shield machine needs to be stopped for disassembly, ground freezing reinforcement, and cast-in-place lining structure construction. The shield machine needs to maintain a water-free environment under the condition of long-term stop. However, during the long-term stop of the shield machine, groundwater may flow into the tunnel from the gap between the shield tail segment and the shield shell, which endangers the safety of tunnel construction. During the tunnel operation process, the waterproof performance of the shield butt joint section needs to be consistent with that of the normal segment, and the joint water stop between the shield tail segment and the cast-in-place section should be impermeable and leakproof. If the water stop measures are slightly poor, groundwater may seep into the tunnel from the joint between the shield tail segment and the cast-in-place section, which endangers the safety of tunnel operation. Based on this, the shield tail water stop in the shield in-situ butt joint process is particularly important for the safety of shield tunnel construction and operation.

[0003] The existing shield tail water stop measures for shield in-situ butt joint mainly include segment external grouting, installation of steel plate water stop belt or water-swelling rubber water stop strip at the joint between the segment and the cast-in-place section.

[0004] Segment external grouting uses grouting to form a water-impermeable layer to block water from the rear part of the shield tail. It is mainly used for shield tail water stop during the stop of the shield machine. It is a temporary waterproof measure during the stop of the construction and still needs to be used in combination with other permanent water stop measures. Moreover, due to the difficulty in guaranteeing the density, uniformity, and long-term water stop effect of grouting, there is a high risk of water stop failure in the face of high water pressure and long-term stop.

[0005] The installation of steel plate water stop belt or water-swelling rubber water stop strip at the joint between the segment and the cast-in-place section is mainly used for joint waterproofing between the segment and the cast-in-place section. It is a permanent waterproof measure for the lining structure and needs to be used in combination with the shield tail water stop measure during construction. However, this measure cannot be used under the condition of long-term stop.

[0006] Based on the above analysis, the existing shield tail water stop measures for shield in-situ butt joint need to comprehensively adopt different measures to guarantee the water stop effect during the stop of the construction and the operation of the tunnel. Moreover, the existing shield tail water stop measures cannot achieve effective shield tail water stop in the face of high water pressure and long-term stop. SUMMARY

[0007] The present application aims to overcome the defects of the prior art, and provides a shield tail water stop device for shield in-situ butt joint and an implementation method, so that the water stop requirements during shield machine shutdown construction and tunnel operation can be met, and the expected water stop effect can be achieved under adverse conditions such as high water pressure and long shutdown.

[0008] The present application is implemented as follows:

[0009] The present application provides a shield tail water stop device for shield in-situ butt joint, which comprises a protective steel plate, a sealing steel plate and fasteners installed along the ring of a segment, the protective steel plate is an annular steel plate closely attached to the segment and a ring joint sealing gasket, the sealing steel plate is an annular steel plate welded to a shield shell, and the protective steel plate and the sealing steel plate are both provided with fastening holes matched with the fasteners, and the fasteners are used to fasten and connect the segment, the protective steel plate and the sealing steel plate.

[0010] Further, the sealing steel plate is provided with a shield tail gap grouting hole near the side close to the shield shell, the shield tail gap grouting hole is used to grout and fill the shield tail gap after the installation of the water stop device, and the protective steel plate and the sealing steel plate are both provided with steel plate gap grouting holes along the ring of the segment, and the steel plate gap grouting holes are used to grout and fill the gaps between the steel plates.

[0011] Further, the protective steel plate is divided into several blocks and installed block by block, and the joints between the blocks are coated with sealant, the sealing steel plate is also divided into several blocks and installed block by block, the sealing steel plate comprises a first steel plate, a second steel plate and a third steel plate installed later, the first steel plate and the second steel plate are both installed synchronously with the protective steel plate, the sealing steel plate is installed staggered with the protective steel plate, the first steel plate is narrower at both ends than the protective steel plate and is connected to the protective steel plate by welding and then installed synchronously, the arc length of the second steel plate is consistent with that of the protective steel plate, the second steel plate can be installed staggered with the protective steel plate by the dislocation reserved by the assembly of the first steel plate and the protective steel plate, the third steel plate is installed in the gap between the first steel plate and the second steel plate, and the joints between the blocks of the sealing steel plate are connected by welding.

[0012] Further, the fasteners are anchor bolts or bolts, and the fastening holes are anchor bolt holes or embedded nuts, and the anchor bolts are connected to the steel bars of the cast-in-place lining structure after being installed with straight-thread sleeves on the side close to the cast-in-place lining structure.

[0013] Further, the shield tail water stop device further comprises anchoring steel plates and connecting steel plates, the anchoring steel plates and the connecting steel plates are both arranged at intervals along the ring joint of the segment, the anchoring steel plates are installed on the inner arc surface of the segment by the method of anchoring or the method of embedding, and one end of the connecting steel plate is welded to the anchoring steel plate and the other end is welded to the sealing steel plate.

[0014] Further, the pipe segment includes a concrete pipe segment and a steel pipe segment, the steel pipe segment is installed at the end of the concrete pipe segment, the steel pipe segment is connected with the concrete pipe segment through a steel nut, the fastener is a bolt, the steel pipe segment, the protective steel plate and the sealing steel plate are all provided with a reserved bolt hole, the steel pipe segment is fastened and connected with the protective steel plate and the sealing steel plate through the bolt, and the bolt is connected with the steel bar in the cast-in-place lining structure.

[0015] Further, the shield tail water stop device further comprises a supporting round steel, the supporting round steel is welded to the side of the protective steel plate facing the pipe segment, and the supporting round steel is synchronously installed with the protective steel plate and serves as the fulcrum of the protective steel plate, so that the protective steel plate can be pressed against the ring joint sealing pad under the extrusion of the sealing steel plate.

[0016] Further, the shield tail water stop device further comprises a stop steel plate, the stop steel plate is a trapezoidal steel plate arranged along the pipe segment in a ring shape, one side of the stop steel plate is welded to the inner wall of the shield shell, and the other side of the stop steel plate is welded to the sealing steel plate, so as to prevent the shield tunneling machine from retreating after the jacks are unloaded, the stop steel plate and the sealing steel plate are provided with a triangular gap at the contact corner portion, so as to avoid stress concentration caused by welding at the corner portion, and a plurality of steel bar holes are reserved in the stop steel plate along the longitudinal direction of the tunnel, and the steel bar holes are used for the through-penetration of the ring-shaped main reinforcement during the construction of the cast-in-place lining structure.

[0017] The application further provides a shield tail water stop implementation method for shield tunneling in the ground.

[0018] S1, detailed size design of the shield tail water stop device is performed according to the site construction condition, and each component of the water stop device is processed in the factory and kept ready for use;

[0019] S2, the protective steel plate and the supporting round steel are welded in blocks in the factory, and then are transported to the site together with other components and kept ready for use;

[0020] S3, the anchor steel plate is installed by planting the steel bar in the inner arc surface of the pipe segment;

[0021] S4, a group of jacks are retracted, holes are drilled at the corresponding positions of the pipe segment for installing fasteners, and the first steel plate in the protective steel plate and the sealing steel plate and the supporting round steel welded in the factory are integrally installed on the pipe segment;

[0022] S5, the protective steel plate is extruded against the ring joint sealing pad of the pipe segment by tightening the fasteners, and after the ring joint sealing pad is extruded in place, the sealing steel plate and the inner arc surface of the shield shell are welded;

[0023] S6, the stop steel plate is installed, and is firmly and closely welded with the sealing steel plate and the inner arc surface of the shield shell;

[0024] S7, the connecting steel plate is installed, and is closely connected with the anchor steel plate and the sealing steel plate;

[0025] S8, repeat step S4 to install the next set of protective steel plates, seal the steel plates and support the round steel, and apply sealant to the joints of the protective steel plates, and use welding to process the joints between the sealing steel plates;

[0026] S9, repeat S4-S8 to complete the installation of the whole ring water stop device;

[0027] S10, grouting is performed on the shield tail gap and the steel plate gap through the shield tail gap grouting hole and the steel plate gap grouting hole, and waterproof reinforcement of the water stop device is performed.

[0028] Further, in order to avoid the freezing and thawing effect of the freezing reinforcement of the shield butt joint area, which causes a large bending internal force of the structure, the welding between the sealing steel plate and the shield shell and the welding between the stop steel plate and the sealing steel plate are not performed during the implementation of steps S5 and S6, and grease is injected into the shield tail during the construction period to achieve water stopping, so that the water stop device and the shield tail maintain flexible contact. After the shield shell is butt jointed and the freezing and thawing effect of the freezing reinforcement area ends, the welding between the sealing steel plate and the shield shell and the welding between the stop steel plate and the sealing steel plate are performed, realizing the conversion from flexible to rigid of the water stop device, meeting the water stopping function requirement while avoiding a large bending internal force on the shield tail segment.

[0029] The present application has the following beneficial effects:

[0030] 1. The water stop device disclosed by the present application realizes waterproof sealing between the segment and the water stop device by pressing the segment ring sealing pad with the protective steel plate, realizes waterproof sealing between the shield tail and the water stop device by welding the sealing steel plate to the inner side of the shield shell, and realizes multiple waterproof combination measures such as shield tail gap grouting sealing and steel plate gap grouting sealing, so as to ensure that the water stop device does not leak under high water pressure.

[0031] 2. The water stop device disclosed by the present application is installed during the shutdown of the shield, and the water stopping effect after the protective steel plate extrudes the segment ring sealing pad and the sealing steel plate is welded to the inner side of the shield shell can meet the water stopping needs during the operation period, realizing the combination of permanent and temporary water stopping of the shield tail.

[0032] 3. The water stop device disclosed by the present application strengthens the connection with the segment lining through the connecting steel plate and the anchor bolt, realizes the connection between the water stop device and the cast-in-place lining structure through the condition of connecting the anchor bolt with the cast-in-place bearing structure steel bar, and realizes the rigid-flex transition between the cast-in-place lining section and the segment section, ensuring the safety of the structure at the joint position of the cast-in-place lining section and the segment section under the conditions of earthquake and uneven settlement during the operation period.

[0033] 4. The water stop device disclosed by the present application can be implemented under the condition of long-time shutdown of the shield, which widens the working conditions applicable to the water stop device. BRIEF DESCRIPTION OF DRAWINGS

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the accompanying drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, the accompanying drawings in the following description only represent some embodiments of the present application, and all other drawings obtained by those of ordinary skill in the art without creative effort based on these drawings belong to the protection scope of the present application.

[0035] Figure 1 A shield tail water stop device sectional view provided by the embodiment of the present application;

[0036] Figure 2 A steel plate arrangement drawing of the shield tail water stop device provided by the embodiment of the present application;

[0037] Figure 3 A shield tail water stop device connected by a steel pipe provided by the embodiment of the present application.

[0038] In the drawings: 1, protective steel plate; 2, sealing steel plate; 3, stop steel plate; 4, support round steel; 5, anchor bolt (or bolt); 6, anchoring steel plate; 7, connecting steel plate; 8, shield tail gap grouting hole; 9, anchor bolt hole (or embedded nut); 10, steel plate gap grouting hole; 11, steel bar hole; 12, steel pipe; 13, steel nut; 14, bolt. DETAILED DESCRIPTION

[0039] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments only represent some embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort belong to the protection scope of the present application.

[0040] As Figures 1-3 , the first embodiment of the present application provides a shield tail water stop device for butt joint in shield ground, which comprises a protective steel plate 1, a sealing steel plate 2, a stop steel plate 3, a support round steel 4, an anchor bolt 5 (or bolt), an anchoring steel plate 6, and a connecting steel plate 7. The protective steel plate 1 is an annular steel plate closely attached to the pipe piece and ring gap sealing pad, which can be installed piece by piece after being divided into several pieces according to the site requirement, and the joints between the pieces are smeared with sealant to avoid welding damage to the pipe piece sealing pad. Anchor bolt holes 9 (or embedded nuts) are reserved, the width of which is consistent with the width after deducting the inner and outer side corner joint slots, which are mainly used for pressing the pipe piece ring gap sealing pad to ensure the water stop between the water stop device and the concrete pipe piece.

[0041] As Figure 2The sealing steel plate 2 is an annular steel plate welded with the shield, and is divided into a first steel plate 2-1, a second steel plate 2-2 and a third steel plate 2-3 installed synchronously with the protective steel plate 1 to ensure that the sealing steel plate 2 can be installed staggeredly with the protective steel plate 1. The first steel plate 2-1 is slightly narrower than the protective steel plate 1 at both ends, and can be connected with the protective steel plate 1 by welding and then installed synchronously; the second steel plate 2-2 is consistent with the arc length of the protective steel plate 1, but is staggered by the reserved stagger of the assembly of the first steel plate 2-1 and the protective steel plate 1, so as to ensure that the second steel plate 2-2 is installed staggeredly with the protective steel plate 1; and the third steel plate 2-3 is installed in the gap between the first steel plate 2-1 and the second steel plate 2-2, and the joints between the blocks of the sealing steel plate 2 are connected by welding.

[0042] As shown in Figure 1 The sealing steel plate 2 is welded with the inner wall of the shield on the outer side to avoid water flowing into the tunnel from the shield tail; an anchor bolt hole 9 (or a pre-buried nut) is reserved in the middle for installing the anchor bolt 5 (or a bolt), which extrudes the protective steel plate 1 under the extrusion force of the anchor bolt 5 to ensure that the protective steel plate 1 can play its effect; and a shield tail gap grouting hole 8 is reserved near the side of the shield for grouting the shield tail gap after the installation of the water stop device to fill the shield tail gap and enhance the water stopping effect.

[0043] The protective steel plate 1 and the sealing steel plate 2 are reserved with a steel plate gap grouting hole 10 along the annular direction of the segment for grouting the gap between the steel plates after the installation of the water stop device to fill the gap and enhance the waterproof effect.

[0044] The stop steel plate 3 is a trapezoidal steel plate arranged along the annular direction of the segment, one side of which is welded to the inner wall of the shield and the other side of which is welded to the sealing steel plate 2, for preventing the retreat of the shield tunneling machine after the unloading of the jack. The stop steel plate 3 is reserved with a certain triangular gap at the corner part in contact with the sealing steel plate 2 to avoid repeated welding at the corner position and affect the welding quality, and to avoid stress concentration caused by welding at the corner part. A steel bar hole 11 is reserved along the longitudinal direction of the tunnel for the annular main reinforcement to pass through when the cast-in-place lining structure is constructed.

[0045] The support round steel 4 is a common round steel bar welded to the inner side of the protective steel plate 1 and slightly higher than the surface of the segment joint, which is installed synchronously with the protective steel plate 1 as the fulcrum of the protective steel plate 1 to ensure that the protective steel plate 1 can press the segment sealing gasket under the extrusion of the sealing steel plate 2.

[0046] The anchor bolt 5 is an anchor bolt installed along the annular direction of the segment, which is installed on the concrete segment through the anchor bolt hole 9 reserved on the protective steel plate 1 and the sealing steel plate 2, and is used for fastening the concrete segment with the protective steel plate 1 and the sealing steel plate 2. The anchor bolt is provided with a through thread, and a straight thread sleeve can be installed near the cast-in-place lining side to be connected with the steel bar of the cast-in-place lining structure, thereby enhancing the connection between the water stop device and the cast-in-place lining structure.

[0047] The anchoring steel plate 6 is a component arranged along the segment ring joint interval and anchored in the inner arc surface of the segment, and the anchoring steel plate 6 is installed on the inner arc surface of the segment by the form of anchoring or the form of pre-embedded part.

[0048] The connecting steel plate 7 is a steel plate arranged along the segment ring joint interval, and the arrangement position is matched with the anchoring steel plate 6, one end is welded to the anchoring steel plate 6, and the other end is welded to the sealing steel plate 2, and is used for strengthening the connection between the water stop device and the assembled segment.

[0049] In addition, in order to avoid large-area punching on the concrete segment to install the anchor bolt, the application also provides another form of connection between the water stop device and the segment:

[0050] As shown in the figure, Figure 3 A steel segment 12 is installed at the end of the concrete segment (concrete segment), the steel segment 12 is connected with the concrete segment through a steel nut 13, bolt holes are reserved on the steel segment 12, and the connection between the steel segment 12 and the water stop device is realized through a bolt 14. The length of the bolt 14 inserted into the cast-in-place lining structure side meets the length requirement of welding with the cast-in-place lining steel, can be used for connecting the steel between the cast-in-place lining structure, and enhances the connection between the water stop device and the cast-in-place lining structure.

[0051] The embodiment two of the application provides a shield tail water stop implementation method for shield ground butt joint:

[0052] Step 1: detailed size design of the water stop device is carried out according to the site construction condition, and each part of the water stop device is processed in the factory for standby.

[0053] Step 2: the protection steel plate 1 and the supporting round steel 4 are divided into blocks for welding in the factory, and then are transported to the site together with other parts for standby.

[0054] Step 3: the anchoring steel plate 6 is installed on the segment inner arc surface by anchoring or pre-embedding.

[0055] Step 4: a group of jacks are returned, holes are drilled or nuts are pre-embedded on the segment corresponding position for installing the anchor bolt 5, and the protection steel plate 1, the first steel plate 2-1 in the sealing steel plate 2 and the supporting round steel 4 welded in the factory are integrally installed on the segment.

[0056] Step 5: the protection steel plate 1 is extruded to the segment ring joint seal pad by tightening the anchor bolt 5, and then the welding between the sealing steel plate 2 and the inner arc surface of the shield shell is carried out.

[0057] Step 6: the stop steel plate 3 is installed, and is welded firmly and closely with the sealing steel plate 2 and the inner arc surface of the shield shell.

[0058] Step 7: the connecting steel plate 7 is installed, and is connected closely with the anchoring steel plate 6 and the water stop device.

[0059] Step 8: Repeat Step 4 to install the whole of the protective steel plate 1, the steel plate 2-2 in the sealing steel plate 2 and the support round steel 4, and apply sealant to the joint of the protective steel plate 1 and handle the joint between the sealing steel plates 2 by welding.

[0060] Step 9: Repeat Steps 4-8 to complete the installation of the whole ring water stop device.

[0061] Step 10: Grout the shield tail gap and the steel plate gap by using the shield tail gap grouting hole 8 and the steel plate gap grouting hole 10, and waterproof the water stop device.

[0062] Preferably, in order to avoid the frost heaving and thawing settlement effect of the structure caused by the freezing reinforcement of the shield butt joint area, the welding between the sealing steel plate 2 and the shield shell and the welding between the stop-retreating steel plate 3 and the sealing steel plate 2 are not performed during the implementation of the above Steps 5 and 6, the grease is injected into the shield tail during the construction period to achieve water stop, the water stop device and the shield tail maintain flexible contact, and the welding between the sealing steel plate 2 and the shield shell and the welding between the stop-retreating steel plate 3 and the sealing steel plate 2 are performed after the butt joint of the shield shell is completed and the frost heaving and thawing settlement effect of the freezing reinforcement area ends, so as to realize the "flexible first and rigid later" conversion of the water stop device, meet the water stop function requirement, and avoid generating large bending internal force on the shield tail segment.

[0063] The contents not described in detail in the specification belong to the prior art known by the person skilled in the art.

[0064] The above only describes the preferred embodiments of the present application and is not used to limit the present application, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A shield tail water-stopping device for underground docking of a shield tunnel, characterized in that: The system includes protective steel plates, sealing steel plates, and fasteners installed circumferentially along the tunnel segments. The protective steel plate is an annular steel plate that fits tightly against the tunnel segments and the circumferential seam sealing gasket. The sealing steel plate is an annular steel plate welded to the shield shell. Both the protective and sealing steel plates have pre-drilled fastening holes for mates with the fasteners. The fasteners are used to securely connect the tunnel segments to the protective and sealing steel plates. The system also includes anchoring steel plates and connecting steel plates, which are spaced apart along the circumferential seams of the tunnel segments. The anchoring steel plates are installed using either rebar installation or pre-embedded components. Installed on the inner arc surface of the tunnel segment, the connecting steel plate is welded at one end to the anchoring steel plate and at the other end to the sealing steel plate; it also includes a backstop steel plate, which is a trapezoidal steel plate arranged circumferentially along the tunnel segment, with one side welded to the inner wall of the shield shell and the other side welded to the sealing steel plate, used to prevent the shield machine from retreating after the jacks unload the force. The triangular gap left at the contact corner of the backstop steel plate and the sealing steel plate avoids stress concentration caused by corner welding. The backstop steel plate has several steel bar holes reserved along the longitudinal direction of the tunnel, which are used for the circumferential main reinforcement bars to pass through during the construction of the cast-in-place lining structure.

2. The shield tail water-stopping device for underground docking of a shield tunnel as described in claim 1, characterized in that: The sealing steel plate has a pre-reserved grouting hole for the shield tail gap near the shield shell side. The grouting hole for the shield tail gap is used to fill the shield tail gap with grout after the water-stopping device is installed. The protective steel plate and the sealing steel plate also have pre-reserved grouting holes for the steel plate gap along the circumferential direction of the pipe segment. The grouting holes for the steel plate gap are used to fill the gap between the steel plates with grout.

3. The shield tail water-stopping device for underground docking of a shield tunnel as described in claim 2, characterized in that: The protective steel plate is divided into several pieces and installed piece by piece. Sealant is applied to the joints between the pieces. The sealing steel plate is divided into several pieces and installed piece by piece. The sealing steel plate includes a first steel plate, a second steel plate, and a third steel plate installed later. The first and second steel plates are installed simultaneously with the protective steel plate. The sealing steel plate and the protective steel plate are installed with staggered joints. The first steel plate is narrower than the protective steel plate at both ends and is connected to the protective steel plate by welding before simultaneous installation. The second steel plate has the same arc length as the protective steel plate. The staggered installation of the second steel plate and the protective steel plate is ensured by the pre-reserved misalignment during the assembly of the first and protective steel plates. The third steel plate is installed in the gap between the first and second steel plates. The joints between the sealing steel plates are connected by welding.

4. The shield tail water-stopping device for underground docking of shield tunnels as described in claim 3, characterized in that: The fastener is an anchor bolt or a bolt, and the fastening hole is an anchor bolt hole or a pre-embedded nut. After the anchor bolt is installed with a straight threaded sleeve on the side close to the cast-in-place lining structure, it is connected to the reinforcing steel of the cast-in-place lining structure.

5. The shield tail water-stopping device for underground docking of a shield tunnel as described in claim 4, characterized in that: The segment includes concrete segments and steel segments. The steel segments are installed at the ends of the concrete segments and are connected to the concrete segments by steel nuts. The fasteners are bolts. Bolt holes are reserved on the steel segments, protective steel plates and sealing steel plates. The steel segments are fastened to the protective steel plates and sealing steel plates by bolts. The bolts are connected to the reinforcing bars in the cast-in-place lining structure.

6. The shield tail water-stopping device for underground docking of a shield tunnel as described in claim 5, characterized in that: It also includes a supporting round steel bar, which is welded to the side of the protective steel plate facing the segment. The supporting round steel bar is installed synchronously with the protective steel plate and serves as a fulcrum for the protective steel plate, ensuring that the protective steel plate can press the circumferential sealing gasket tightly under the squeezing action of the sealing steel plate.

7. A method for implementing shield tail water-stopping during underground docking of a shield tunnel, applied to the shield tail water-stopping device for underground docking of a shield tunnel as described in claim 6, characterized in that, Includes the following steps: S1. Design the detailed dimensions of the shield tail waterstop device according to the on-site construction conditions, and process all components of the waterstop device in the factory for later use. S2. The protective steel plates and supporting round steel are welded in sections in the factory, and then transported to the site along with other components for use. S3. Install anchor steel plates or pre-embed anchor steel plates by planting reinforcement bars on the inner arc surface of the segment. S4. Retract a set of jacks, drill holes or pre-embed nuts at the corresponding positions of the segments for fastener installation, and install the protective steel plate, the first steel plate in the sealing steel plate, and the supporting round steel as a whole onto the segments after the factory welding. S5. Tighten the fasteners to squeeze the protective steel plate into the circumferential seam sealing gasket of the segment. After the circumferential seam sealing gasket is squeezed into place, weld the sealing steel plate to the inner arc surface of the shield. S6. Install the anti-reverse steel plate and weld it securely and tightly to the sealing steel plate and the inner arc surface of the shield. S7. Install the connecting steel plate to ensure a tight connection with the anchoring steel plate and the sealing steel plate; S8. Repeat step S4 to install the next set of protective steel plates, sealing steel plates and supporting round steel as a whole, apply sealant to the joints of the protective steel plates, and weld the joints between the sealing steel plates. S9. Repeat S4~S8 to complete the installation of the whole-ring water-stop device; S10. Grouting is performed on the shield tail gap and steel plate gap using the grouting holes in the shield tail gap and steel plate gap to reinforce the waterproofing of the water-stopping device.

8. The method for implementing water-stopping at the shield tail during underground docking of a shield tunnel as described in claim 7, characterized in that: To avoid the frost heave and thaw settlement effect during the freezing and reinforcement of the shield docking area, which would cause large bending internal forces to the structure, welding between the sealing steel plate and the shield shell, as well as welding between the anti-recession steel plate and the sealing steel plate, will not be carried out during steps S5 and S6. During the construction period, grease will be continuously injected into the shield tail to achieve water stoppage, keeping the water-stopping device in flexible contact with the shield tail. After the shield docking is completed and the frost heave and thaw settlement effect in the frozen and reinforced area is over, welding between the sealing steel plate and the shield shell, as well as welding between the anti-recession steel plate and the sealing steel plate, will be carried out. This achieves the transformation of the water-stopping device from flexible to rigid, meeting the water-stopping function requirements while avoiding large bending internal forces on the shield tail segments.

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