Internal pressure type water and soil pressure control steel sleeve and construction method

Abstract

The embodiment of the present invention provides an internal pressure type water and soil pressure control steel sleeve, including a sleeve, a cover plate, a base, a reaction frame and a flat support, wherein the cover plate is provided with a sealed pressure regulating bag on the inner side surface inside the sleeve, and the sealed pressure regulating bag is provided with a pressure injection pipe, and the pressure injection pipe passes through the cover plate so that the sealed pressure regulating bag is connected to the outside. The embodiment of the present invention arranges a sealed pressure regulating bag in the sleeve, and uses the water injection port on the sleeve to realize water pressure control during pressure regulation, and realizes soil pressure control by injecting liquid or gas into the sealed pressure regulating bag. The combination of the two realizes precise control of water and soil pressure before and after the portal is broken and during the shield receiving process; in addition, the water pressure and soil pressure in the sleeve are independently controlled respectively, and the water and soil pressure adjustment range is larger, which can meet the water and soil pressure balance requirements of shield receiving in ultra-deep burial, high-pressure water and frequency-changing formations.

Description

Technical Field

[0001] The invention relates to the technical field of shield construction, and in particular to an internal pressure type water and soil pressure control steel sleeve and a construction method. Background Art

[0002] The risk control of shield machine receiving construction is particularly critical in the entire subway shield construction process. At present, the commonly used methods to improve the safety of shield receiving construction include: stratum reinforcement around the tunnel portal, underwater receiving method, NOMST method and steel sleeve receiving method.

[0003] Among them, the steel sleeve receiving method has little impact on the surrounding environment, is safe and reliable, and saves space. It has been widely used in shield tunnel projects in water-rich soft soil strata at home and abroad. The conventional shield receiving steel sleeve is mainly a circular "bucket-type" structure with an open end and a sealed bottom at the other end. The open end is connected to the pre-buried annular steel plate of the tunnel portal to form a closed container. The container is filled with sand and water to form and maintain a certain pressure to balance the water and soil pressure of the stratum to the inside of the steel sleeve when the shield is receiving.

[0004] During the construction process, the control of the water and soil pressure balance between the filling material in the sleeve and the stratum is the key to determining whether the shield machine can be successfully received. Improper handling can easily cause engineering accidents such as water gushing, sand gushing and collapse. During the process of breaking through the tunnel gate and excavating in the steel sleeve, the conventional shield machine can only roughly control the water and soil pressure of the filling material in the steel sleeve as a whole, and the pressure adjustment range is also small, and it is impossible to accurately control the dynamic balance of water pressure and soil pressure between the stratum and the filling material in the sleeve. Summary of the invention

[0005] In view of the above problems, an embodiment of the present invention provides an internal pressure type water and soil pressure control steel sleeve and a construction method.

[0006] One aspect of the implementation of the present invention provides an internal pressure type water and soil pressure control steel sleeve, including a sleeve, a cover plate, a base, a reaction frame and a horizontal support, wherein the sleeve is fixed on the base, one end of the sleeve is sealed and connected to the shield tunnel portal, and the other end is closed by the cover plate, the reaction frame is vertically pressed against between the bottom plate and the middle plate of the shield tunnel, the outer side surface of the cover plate is fixedly connected to the reaction frame by a horizontal support, a sealed pressure regulating bag is arranged on the inner side surface of the cover plate located inside the sleeve, and a pressure injection pipe is arranged on the sealed pressure regulating bag, and the pressure injection pipe passes through the cover plate to connect the sealed pressure regulating bag with the outside.

[0007] Compared with the prior art, the beneficial effects of the present invention are: a sealed pressure-regulating bag is arranged in the sleeve, and the water pressure is controlled by utilizing the water injection port on the sleeve during pressure regulation, and the soil pressure is controlled by injecting liquid or water into the sealed pressure-regulating bag, and the combination of the two can realize precise control of the water and soil pressure before and after the portal is broken and during the shield receiving process; in addition, the water pressure and soil pressure in the sleeve are independently controlled, and the water and soil pressure adjustment range is larger, which can meet the water and soil pressure balance requirements of shield receiving in ultra-deep buried, high-pressure water and frequency-changing strata.

[0008] Optionally, the sleeve is formed by axially assembling annular components in sequence, wherein an annular flange is installed at the barrel openings where adjacent annular components are connected to each other, and the adjacent annular components are fixedly connected by the annular flange and bolts;

[0009] The annular component is formed by two upper and lower semi-annular components being fastened and fixed relative to each other, wherein a longitudinal flange is installed on the sides of the two semi-annular components connected to each other, and the upper and lower semi-annular components are fixedly connected by the longitudinal flange and bolts.

[0010] Optionally, both the annular flange and the longitudinal flange are of a bidirectional flange structure, the cross-section of the inner flange inside the sleeve is trapezoidal, and the outer flange outside the sleeve is evenly distributed with bolt holes.

[0011] Optionally, after two adjacent inner flanges are fastened, a sealing strip is provided on the outside, the cross section of the sealing strip is concave, and the angle between the two waists of the groove on the sealing strip and the groove bottom is the same as the groove angle of the inner flange.

[0012] Optionally, soil retaining strips are extended to both sides from the bottom of the sealing strip.

[0013] Optionally, the annular component includes a transition ring, a standard ring, a packing ring and a shorting ring;

[0014] The tube opening on one side of the transition ring is sealed and connected to the shield tunnel portal, a sand filling port and a water injection port are provided on the packing ring, and the tube opening on one side of the short-circuit ring is sealed by a cover plate.

[0015] Optionally, ribs are provided on the outer wall of the annular component in both the circumferential direction and the axial direction.

[0016] Optionally, a diagonal brace is fixedly connected between the reaction frame and the bottom plate of the shield tunnel;

[0017] A rib plate is arranged on the outer side of the cover plate, a pressure plate is arranged on the rib plate, one end of the flat support is fixed to the pressure plate, and the other end is fixed to the reaction frame.

[0018] Optionally, the base includes a plurality of vertically arranged load-bearing plates, the top surfaces of the load-bearing plates are arc-shaped, and connecting strips are fixedly connected between the load-bearing plates.

[0019] Another aspect of the present invention is to provide a construction method for receiving a shield using the internal pressure type water and soil pressure control steel sleeve, comprising:

[0020] Level and harden the construction site, transport the load-bearing plates and contact strips included in the base to the designated location of the construction site, and complete the erection and fixing of the base;

[0021] The number of standard rings is determined according to the design requirements. The base is used as the installation platform. The various annular components including the transition ring, standard ring, packing ring and short-circuit ring are assembled and connected in sequence according to the design sequence to form a sleeve.

[0022] Place the mouth of the transition ring of the sleeve against the tunnel portal of the shield tunnel and weld it to the embedded parts at the tunnel portal. Apply waterproof material to the weld to seal it.

[0023] Install sealing strips on the inner flanges of the annular flange and the longitudinal flange at the connection of the annular component;

[0024] A sealed pressure regulating bag is installed on the inner side of the cover plate, and a pressure injection pipe on the sealed pressure regulating bag passes through the cover plate so that the sealed pressure regulating bag is connected to the outside, and the cover plate is assembled to the tube mouth of the short-circuit ring;

[0025] A reaction frame is set up between the bottom plate and the middle plate of the shield tunnel, a flat brace is fixed between the reaction frame and the pressure plate of the cover plate, and an inclined brace is fixed between the middle part of the reaction frame and the bottom plate;

[0026] Fill sand and water into the sleeve through the sand filling port and water injection port on the packing ring. During the filling process, bury the soil pressure gauge and pore water pressure gauge. After filling, seal the sand filling port.

[0027] Before breaking the tunnel portal, adjust the water injection port pressure and inject liquid or air into the sealed pressure regulating bag to adjust the pressure of the sealed pressure regulating bag. During the pressure adjustment process, continuously monitor the data of the soil pressure gauge and pore water pressure gauge in the sleeve to ensure that the water pressure and soil pressure in the sleeve meet the design requirements and keep the pressure stable.

[0028] After the tunnel door is broken, adjust the pressure of the sealing pressure regulating bag and the water injection port pressure to restore the balance of water pressure and soil pressure in the sleeve;

[0029] During the shield tunneling process in the sleeve, the pressure of the sealing pressure regulating bag and the water injection port is monitored and adjusted in real time to maintain the dynamic balance of water and soil pressure during tunneling until the shield is received. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The drawings described herein are used to provide a further understanding of the present invention, constitute a part of the present application, and do not constitute a limitation of the present invention. In the drawings:

[0031] Figure 1A schematic structural diagram of an internal pressure type water and soil pressure control steel sleeve provided in an embodiment of the present invention;

[0032] Figure 2 A schematic diagram of a longitudinal cross-section structure of an internal pressure type water and soil pressure control steel sleeve provided in an embodiment of the present invention;

[0033] Figure 3 A schematic diagram of the structure of a sleeve provided in an embodiment of the present invention;

[0034] Figure 4 A schematic diagram of a partial cross-section structure of an annular flange provided in an embodiment of the present invention;

[0035] Figure 5 A schematic diagram of a partial cross-section structure of a longitudinal flange provided in an embodiment of the present invention;

[0036] Figure 6 A schematic diagram of the cross-sectional structure of a sealing card strip provided by an embodiment of the present invention;

[0037] Figure 7 A schematic structural diagram of an annular sealing strip provided by an embodiment of the present invention;

[0038] Figure 8 A schematic diagram of the structure of a linear sealing strip provided by an embodiment of the present invention;

[0039] Fig. 9 A schematic diagram of the structure of a sealing strip and a flange connection provided by an embodiment of the present invention;

[0040] Fig.10 A schematic structural diagram of a cover plate provided by an embodiment of the present invention;

[0041] Fig.11 A schematic structural diagram of a base provided in an embodiment of the present invention.

[0042] Among them, sleeve 1, cover plate 2, base 3, reaction frame 4, flat support 5, sealing pressure regulating bag 6, pressure injection pipe 7, annular flange 8, transition ring 9, standard ring 10, packing ring 11, short-circuit ring 12, sand filling port 13, water injection port 14, longitudinal flange 15, inner flange 16, outer flange 17, sealing card strip 18, retaining strip 19, rib plate 20, diagonal support 21, pressure plate 22, load-bearing plate 23, and connecting strip 24. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments and the accompanying drawings. Here, the illustrative embodiments of the present invention and their descriptions are used to explain the present invention, but are not intended to limit the present invention.

[0044] See also Figure 1 and Figure 2 An internal pressure type water and soil pressure control steel sleeve provided by an embodiment of the present invention comprises a sleeve 1, a cover plate 2, a base 3, a reaction frame 4 and a flat support 5, wherein the sleeve 1 is fixed on the base 3, the base 3 is horizontally placed on a flat ground to support and fix the sleeve 1, the sleeve 1 is coaxial with the circular cross-section of the shield tunnel, one end of the sleeve 1 is sealed and connected to the shield tunnel portal, and the other end is closed by the cover plate 2, the reaction frame 4 is vertically pressed against between the bottom plate and the middle plate of the shield tunnel, the outer side surface of the cover plate 2 is fixedly connected to the reaction frame 4 by the flat support 5, and a sealed pressure regulating bag 6 is arranged on the inner side surface of the cover plate 2 located inside the sleeve, and a pressure injection pipe 7 is arranged on the sealed pressure regulating bag 6, and the pressure injection pipe 7 passes through the cover plate 2 to connect the sealed pressure regulating bag 6 with the outside.

[0045] See also Figure 3 The sleeve 1 is formed by axially assembling annular components in sequence, and the axes of the annular components are in line with each other. An annular flange 8 is installed at the barrel mouth where adjacent annular components are connected to each other, and the adjacent annular components are fixedly connected by the annular flange 8 and bolts; specifically, the annular components include a transition ring 9, a standard ring 10, a packing ring 11 and a shorting ring 12;

[0046] The standard ring 10 is a standard annular component with a standard axial length. During construction, the number of standard rings 10 is determined according to the design length of the sleeve 1; the transition ring 9 is shorter than the standard ring 10, and only one side of the tube mouth is installed with the annular flange 8, and the other side of the tube mouth is sealed and connected to the shield tunnel portal; the packing ring 11 is provided with a sand filling port 13 and a water injection port 14, and the short-circuit ring 12 is a length supplement provided to adapt to the specific design length of the sleeve 1, and one side of the tube mouth is sealed by a cover plate 2.

[0047] In practice, the annular component is formed by two upper and lower semi-annular components that are fastened relative to each other, wherein a longitudinal flange 15 is installed on the sides of the two semi-annular components that are connected to each other, and the upper and lower semi-annular components are fixedly connected by the longitudinal flange 15 and bolts.

[0048] See also Figure 4 and Figure 5 The annular flange 8 and the longitudinal flange 15 are both bidirectional flange structures, that is, a flange section extends inside and outside the sleeve, wherein the cross-section of the inner flange 16 inside the sleeve 1 is trapezoidal, and the outer flange 17 outside the sleeve 1 is evenly distributed with bolt holes.

[0049] See also Figure 6 , Figure 7 , Figure 8 and Fig. 9After the annular component is assembled into the sleeve 1, the two adjacent inner flanges 16 are tightly attached together under the tightening action of the bolts. Thereafter, a sealing strip 18 can be sleeved on the outside of the two adjacent inner flanges 16. The cross-section of the sealing strip 18 is concave in shape. The angle between the two waists of the groove on the sealing strip 18 and the bottom of the groove is the same as the groove angle of the inner flange 16. The sealing strip 18 can be sealed and plugged into the flange connection part to achieve a sealing effect.

[0050] In practice, the sealing strip 18 is divided into two types: annular sealing strip and linear sealing strip, which are respectively adapted to the annular flange 8 and the longitudinal flange 15. In one implementation, a retaining strip 19 extends from the bottom of the sealing strip 18 to both sides, and sealing strips are pasted on both sides of the groove on the sealing strip 18 to enhance the sealing and waterproof effect.

[0051] The flange connections of each annular component in the sleeve 1 are sealed with a sealing strip 18. The sealing strip 18 is subjected to water and soil pressure directed toward the flange. The tensile deformation of the flange connection is also limited by the reaction force of the sealing strip. That is, the sealing strip 18 arranged on the inner flange of the flange connection is pressed tighter and tighter under the action of the packing pressure, thereby avoiding water leakage at the connection.

[0052] In practice, ribs 20 may be provided on the outer wall of the annular component in both the circumferential direction and the axial direction to enhance the strength of the annular component.

[0053] A diagonal brace 21 is fixedly connected between the reaction frame 4 and the bottom plate of the shield tunnel to increase the firmness of the reaction frame 4 .

[0054] A rib 20 is provided on the outer surface of the cover plate 2, and a pressure plate 22 is provided on the rib 20. One end of the flat support 5 is fixed to the pressure plate 22, and the other end is fixed to the reaction frame 4. The rib 20 is used to improve the strength of the cover plate 2, and the pressure plate 22 is used to improve the compressive stiffness of the cover plate 2 under the pressure of the flat support 5, thereby reducing its stress concentration and local deformation.

[0055] In practice, the base 3 includes a plurality of vertically arranged load-bearing plates 23 , the top surface of the load-bearing plates 23 is arc-shaped, the arc diameter is equal to or slightly larger than the outer diameter of the annular ribs on the surface of the sleeve 1 , and connecting strips 24 are fixedly connected between the load-bearing plates 23 .

[0056] When the embodiment of the present invention uses the above-mentioned internal pressure type water and soil pressure control steel sleeve for shield receiving, it is necessary to level and harden the construction site, transport the load-bearing plate 23 and the connecting bar 24 included in the base 3 to the designated position of the construction site, and complete the erection and fixation of the base 3;

[0057] The number of standard rings 10 is determined according to design requirements, and the base 3 is used as an installation platform. The various annular components including the transition ring 9, the standard ring 10, the packing ring 11 and the shorting ring 12 are assembled and connected in sequence according to the design sequence to form a sleeve 1;

[0058] The mouth of the transition ring 9 of the sleeve 1 is pressed against the tunnel portal of the shield tunnel and welded to the embedded parts at the tunnel portal, and the weld is sealed with waterproof material;

[0059] Install a sealing strip 18 on the inner edge of the annular flange 8 and the longitudinal flange 15 at the connection of the annular component;

[0060] A sealed pressure regulating bag 6 is installed on the inner side of the cover plate 2, and a pressure injection pipe 7 on the sealed pressure regulating bag 6 passes through the cover plate 2 so that the sealed pressure regulating bag 6 is connected to the outside, and the cover plate 2 is assembled to the tube mouth of the short-circuit ring 12;

[0061] A reaction frame 4 is set up between the bottom plate and the middle plate of the shield tunnel, a flat support 5 is fixed between the reaction frame 4 and the pressure plate 22 of the cover plate 2, and an oblique support 21 is fixed between the middle part of the reaction frame 4 and the bottom plate;

[0062] Sand and water are filled into the sleeve 1 through the sand filling port 13 and the water injection port 14 on the packing ring 11. During the filling process, a soil pressure gauge and a pore water pressure gauge are buried. After the filling is completed, the sand filling port 13 is sealed.

[0063] Before breaking the tunnel door, adjust the pressure of the water injection port 14 and inject liquid or air into the sealed pressure regulating bag 6 to adjust the pressure of the sealed pressure regulating bag 6. During the pressure regulation process, continuously monitor the data of the soil pressure gauge and pore water pressure gauge in the sleeve 1 to make the water pressure and soil pressure in the sleeve 1 meet the design requirements and keep the pressure stable.

[0064] After the tunnel door is broken, adjust the pressure of the sealing pressure regulating bag 6 and the pressure of the water injection port to restore the balance of water pressure and soil pressure in the sleeve 1;

[0065] During the tunneling process of the shield in the sleeve, the pressure of the sealed pressure regulating bag 6 and the pressure of the water injection port 14 are monitored and adjusted in real time to maintain the dynamic balance of water and soil pressure during tunneling until the shield is received.

[0066] Embodiment 1:

[0067] Embodiment background:

[0068] The total length of a subway shield section is 720m, the center elevation of the receiving section tunnel is -16m, and the ground elevation is +4.2m. According to the geological survey report, the shield receiving section is located in the sandy silt layer, which is a pressurized aquifer and is prone to water and sand gushing accidents under hydrodynamic conditions; in addition, there are multiple Φ450 sewage pipes near the shield receiving section, with the minimum distance from the station being only 3m; the minimum clear distance between the shield receiving tunnel and a river flood control wall is only 4m. In view of the limited construction site conditions and the complex hydrogeological environment, the proposed water and soil pressure active dynamic control steel sleeve structure is adopted to complete the shield reception, and its construction steps include:

[0069] Step 1: Level and harden the construction site, use a crane to lift the load-bearing plate and connecting bars included in the base into the bottom of the shield shaft, and set up and fix them at the designated location on the site;

[0070] Step 2: Using the base as the installation platform, the crane and manual labor are used to assemble the transition ring (1 ring), standard ring (3 rings), packing ring (1 ring) and short-circuit ring (1 ring) in sequence according to the design sequence, and connect them by bolts to form a complete sleeve;

[0071] Step 3: Make the transition ring end of the sleeve rest against the tunnel portal, and weld it to the embedded part of the tunnel portal, and apply waterproof material to the weld to seal it;

[0072] Step 4: insert the sealing clip into the inner flange of the flange at the connection of each annular component to clamp and seal;

[0073] Step 5: Assemble the cover plate with the sealed pressure regulating bag attached to the end of the short-circuit ring of the sleeve and connect them with bolts;

[0074] Step 6: Set up the reaction frame, diagonal brace and horizontal brace, and the end of the horizontal brace supports the pressure plate of the cover plate;

[0075] Step 7: Fill the sleeve with sand and water from the sand filling port and water injection port, bury the soil pressure gauge and pore water pressure gauge, and seal the sand filling port and water injection port. At this point, the shield receiving construction preparation stage is completed;

[0076] Step 8: Before breaking the tunnel portal, adjust the pressure of the sealing pressure regulating bag and the water pressure of the water injection port, and start to continuously monitor the data of the soil pressure gauge and pore water pressure gauge in the sleeve, so that the water pressure and soil pressure in the sleeve meet the design requirements and keep the pressure value stable;

[0077] Step 9: After the tunnel door is broken, adjust the sealed pressure regulating bag pressure and water pressure at the water injection port according to the changes in the monitoring data of the soil pressure gauge and the pore water pressure gauge to quickly restore the balance of water pressure and soil pressure;

[0078] Step 10. During the excavation process of the shield inside the sleeve, monitor and adjust the pressure of the sealing pressure regulating bag and the water pressure of the water injection port in real time to maintain the dynamic balance of water and soil pressure during excavation until the shield is received.

[0079] The above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. An internal pressure type water and soil pressure control steel sleeve, comprising a sleeve, a cover plate, a base, a reaction frame and a flat support, wherein: The sleeve is fixed on the base, one end of the sleeve is sealed and connected to the shield tunnel portal, and the other end is closed by a cover plate, the reaction frame is vertically pressed against the bottom plate and the middle plate of the shield tunnel, and the outer side surface of the cover plate is fixedly connected to the reaction frame by a flat support, characterized in that a sealed pressure regulating bag is provided on the inner side surface of the cover plate inside the sleeve, and a pressure injection pipe is provided on the sealed pressure regulating bag, and the pressure injection pipe passes through the cover plate to connect the sealed pressure regulating bag with the outside; when regulating the pressure, the water pressure is controlled by the water injection port on the sleeve, and the soil pressure is controlled by injecting liquid or air into the sealed pressure regulating bag, and the combination of the two can realize the precise control of the water and soil pressure before and after the portal is broken and during the shield receiving process; in addition, the water pressure and soil pressure in the sleeve are independently controlled respectively, and the water and soil pressure adjustment range is larger, which can meet the water and soil pressure balance requirements of the shield receiving in ultra-deep buried, high-pressure water and frequency-changing strata.

2. The internal pressure type water and soil pressure control steel sleeve according to claim 1 is characterized in that: The sleeve is formed by axially assembling annular components in sequence, wherein an annular flange is installed at the barrel mouth where adjacent annular components are connected to each other, and the adjacent annular components are fixedly connected by the annular flange and bolts; The annular component is formed by two upper and lower semi-annular components being fastened and fixed relative to each other, wherein a longitudinal flange is installed on the sides of the two semi-annular components connected to each other, and the upper and lower semi-annular components are fixedly connected by the longitudinal flange and bolts.

3. The internal pressure type water and soil pressure control steel sleeve according to claim 2, characterized in that: The annular flange and the longitudinal flange are both bidirectional flange structures, the cross section of the inner flange inside the sleeve is trapezoidal, and bolt holes are evenly distributed on the outer flange outside the sleeve.

4. The internal pressure type water and soil pressure control steel sleeve according to claim 3 is characterized in that: After two adjacent inner flanges are fastened, a sealing strip is sleeved outside. The cross section of the sealing strip is concave. The angle between the two waists of the groove on the sealing strip and the groove bottom is the same as the groove angle of the inner flange.

5. The internal pressure type water and soil pressure control steel sleeve according to claim 4, characterized in that: A soil retaining strip is extended to both sides from the bottom of the sealing strip.

6. The internal pressure type water and soil pressure control steel sleeve according to claim 2, characterized in that: The annular components include transition rings, standard rings, packing rings and short-circuit rings; The tube opening on one side of the transition ring is sealed and connected to the shield tunnel portal, a sand filling port and a water injection port are provided on the packing ring, and the tube opening on one side of the short-circuit ring is sealed by a cover plate.

7. The internal pressure type water and soil pressure control steel sleeve according to claim 2, characterized in that: The outer wall of the annular component is provided with ribs in the annular direction and the axial direction.

8. The internal pressure type water and soil pressure control steel sleeve according to claim 1, characterized in that: The reaction frame is fixedly connected to the bottom plate of the shield tunnel with a diagonal brace; A rib plate is arranged on the outer side of the cover plate, a pressure plate is arranged on the rib plate, one end of the flat support is fixed to the pressure plate, and the other end is fixed to the reaction frame.

9. The internal pressure type water and soil pressure control steel sleeve according to claim 1, characterized in that: The base comprises a plurality of vertically arranged load-bearing plates, the top surfaces of the load-bearing plates are arc-shaped, and connecting strips are fixedly connected between the load-bearing plates.

10. A construction method for receiving a shield using the internal pressure type water and soil pressure control steel sleeve according to any one of claims 1 to 9, characterized in that: include: Level and harden the construction site, transport the load-bearing plates and contact strips included in the base to the designated location of the construction site, and complete the erection and fixing of the base; The number of standard rings is determined according to the design requirements. The base is used as the installation platform. The various annular components including the transition ring, standard ring, packing ring and short-circuit ring are assembled and connected in sequence according to the design sequence to form a sleeve. Place the mouth of the transition ring of the sleeve against the tunnel portal of the shield tunnel and weld it to the embedded parts at the tunnel portal. Apply waterproof material to the weld to seal it. Install sealing strips on the inner flanges of the annular flange and the longitudinal flange at the connection of the annular component; A sealed pressure regulating bag is installed on the inner side of the cover plate, and a pressure injection pipe on the sealed pressure regulating bag passes through the cover plate so that the sealed pressure regulating bag is connected to the outside, and the cover plate is assembled to the tube mouth of the short-circuit ring; A reaction frame is set up between the bottom plate and the middle plate of the shield tunnel, a flat brace is fixed between the reaction frame and the pressure plate of the cover plate, and an inclined brace is fixed between the middle part of the reaction frame and the bottom plate; Sand and water are filled into the sleeve through the sand filling port and water injection port on the packing ring. During the filling process, an earth pressure gauge and a pore water pressure gauge are buried. After the filling is complete, the sand filling port is sealed. Before breaking the tunnel portal, adjust the water injection port pressure and inject liquid or air into the sealed pressure regulating bag to adjust the pressure of the sealed pressure regulating bag. During the pressure adjustment process, continuously monitor the data of the soil pressure gauge and pore water pressure gauge in the sleeve to ensure that the water pressure and soil pressure in the sleeve meet the design requirements and keep the pressure stable. After the tunnel door is broken, adjust the pressure of the sealing pressure regulating bag and the water injection port pressure to restore the balance of water pressure and soil pressure in the sleeve; During the shield tunneling process in the sleeve, the pressure of the sealing pressure regulating bag and the water injection port is monitored and adjusted in real time to maintain the dynamic balance of water and soil pressure during tunneling until the shield is received.

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