A TBM tail seal and synchronous grouting integrated device for soft soil layer

Abstract

The utility model discloses a kind of TBM shield tail sealing and synchronous grouting integration device for soft soil layer, belong to tunneling equipment technical field.The utility model includes shield tail assembly, sealing pipe assembly, grouting pipe, two shield tail sealing assemblies and air pressure sensor.The utility model is by grouting pipe front position arrangement, and pressure balance cavity is formed between two shield tail sealing assemblies, utilizes air pressure sensor to monitor pressure in cavity in real time, and dynamic pressure regulation is carried out by sealing pipe assembly connection external air source, constructs the integration working mode of "first grouting, then balance, after sealing", realizes active pressure management and function cooperation, significantly improves sealing reliability, prolongs component service life and enhances stratum subsidence control ability.

Description

Technical Field

[0001] This utility model relates to the field of tunnel boring equipment technology, specifically to an integrated device for TBM tail sealing and synchronous grouting in soft soil strata. Background Technology

[0002] Full-face tunnel boring machines (TBMs), especially shield tunneling machines, have become key equipment for urban tunnel construction. During the TBM excavation process, the shield tail is a key component connecting the shield shell and the precast tunnel segments. Its core functions are twofold: first, to prevent groundwater and soil from entering the machine body through the shield tail sealing system; and second, to fill the construction gap between the shield body and the tunnel segments in a timely manner through the synchronous grouting system, so as to support the strata and control settlement.

[0003] When constructing in soft soil strata, the aforementioned functions face severe challenges. Soft soil is characterized by high water content, low bearing capacity, and high fluidity, posing a continuous high-pressure threat to the shield tail sealing performance. Currently, the mainstream shield tail sealing method involves setting multiple wire brush seals and their corresponding grease injection chambers on the shield tail shell, relying on the close contact between the sealing brushes and the segments and the filling of grease to achieve sealing. However, this passive sealing method will significantly reduce its reliability when encountering pressure fluctuations or wear of the sealing brushes, posing a risk of seal failure.

[0004] Existing synchronous grouting systems are typically arranged independently of the sealing system, with the grouting pipe usually located behind or passing through the tail shield sealing system. This split design results in insufficient coordination between the sealing and grouting functions, leading to the following inherent defects:

[0005] First, when the grouting pressure is not properly controlled, the high-pressure grout may break through the unstable sealing barrier, directly leading to seal failure, which is the so-called "breakdown" phenomenon.

[0006] Secondly, the combined effect of high-pressure water and soil pressure from the external strata and internal grouting pressure on the sealing system keeps the sealing brush under a complex and alternating stress state, accelerating its fatigue and wear, and shortening its service life.

[0007] Furthermore, existing technologies lack effective means of monitoring and actively controlling the internal pressure of the shield tail sealing area, leaving the entire system in a "passive response" state, making it difficult to adapt to the complex and varied geological conditions of soft soil strata. Utility Model Content

[0008] The purpose of this invention is to provide an integrated device for TBM tail sealing and synchronous grouting in soft soil strata. By integrating the tail sealing assembly, grouting pipe and pressure balancing system composed of air pressure sensor and sealing pipe assembly into the tail shell, a specific pressure balancing chamber is formed. This solves the technical problems in the prior art where the tail sealing and synchronous grouting functions are disconnected and have poor coordination, which can easily lead to sealing failure, increased wear of the tail brush and high risk of ground subsidence under high pressure in soft soil strata.

[0009] This utility model is achieved through the following technical solution:

[0010] This utility model is an integrated device for TBM tail sealing and synchronous grouting in soft soil strata, including a tail shield assembly, a sealing pipe assembly, a grouting pipe, a pressure sensor, and two tail shield sealing assemblies.

[0011] The shield tail assembly includes a shield tail housing, a through groove on the circumferential surface of the shield tail housing, an axially penetrating mounting groove on the shield tail housing, and a groove on the end face of the shield tail housing.

[0012] The sealing tube assembly includes a square tube and a connecting tube fixed to the bottom of the square tube, with the square tube embedded in a through groove.

[0013] The grouting pipe is embedded in the installation groove.

[0014] The tail shield sealing assembly includes two tail shield sealing brushes and a grease chamber located between the two tail shield sealing brushes. The two tail shield sealing assemblies are disposed on the tail shield housing and form a pressure balance chamber.

[0015] The air pressure sensor is fixedly installed on the tail shell of the shield and is located in the pressure balance chamber.

[0016] Furthermore, there are multiple through slots, mounting slots, and recesses, and the mounting slots and recesses are connected.

[0017] Furthermore, the connecting pipe passes through the through groove.

[0018] Furthermore, there are multiple sealing tube assemblies, and each sealing tube assembly is distributed at equal angles along the circumference of the tail shield shell.

[0019] Furthermore, the square tube and the connecting pipe are connected.

[0020] This utility model has the following beneficial effects:

[0021] 1. This utility model integrates the grouting pipe, pressure balance chamber, and shield tail sealing assembly into one unit, and uses a pressure sensor to monitor and the sealing pipe assembly to regulate the pressure in the pressure balance chamber. The pressure balance chamber acts as a dynamic buffer zone, effectively isolating the direct impact of the drastic fluctuations in external grouting pressure and formation pressure on the inner main seal, preventing the risk of grout "breakthrough" of the seal and high-pressure water and soil intrusion, and greatly improving the sealing reliability in soft soil strata.

[0022] 2. This utility model, by having a pressure balancing chamber that bears and stabilizes most of the external pressure fluctuations, avoids excessive fatigue and wear caused by complex alternating stress, reduces the replacement frequency and maintenance cost of the sealing brush, extends the service life of the entire shield tail system, and ensures the continuity of long-distance tunnel construction.

[0023] 3. The integrated design of this utility model makes synchronous grouting more timely and effective. The grout can form a stable support at the shield tail gap in the first time, which can adapt to the complex pressure changes of soft soil strata and form a dynamic and stable "pressure ring" to maintain balance with the external strata pressure. This allows for more precise control of strata deformation and minimizes surface settlement. It is particularly suitable for tunnel construction in urban areas that are sensitive to settlement.

[0024] Of course, any product implementing this utility model does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0025] Figure 1 A schematic diagram of the integrated device for TBM tail sealing and synchronous grouting;

[0026] Figure 2 A schematic diagram of the back structure of the integrated TBM tail seal and synchronous grouting device;

[0027] Figure 3 This is a schematic diagram of the shield tail assembly.

[0028] Figure 4 This is a schematic diagram of the sealing tube assembly.

[0029] In the diagram: 1. Tail shield assembly; 101. Tail shield shell; 102. Through groove; 103. Mounting groove; 104. Groove; 2. Sealing pipe assembly; 201. Square tube; 202. Connecting pipe; 3. Tail shield sealing assembly; 301. Tail shield sealing brush; 302. Grease chamber; 4. Grouting pipe; 5. Air pressure sensor; 6. Pressure balance chamber. Detailed Implementation

[0030] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0031] Please see Figure 1-4 This utility model provides a technical solution: an integrated device for TBM tail sealing and synchronous grouting in soft soil strata, including a tail shield assembly 1, a sealing pipe assembly 2, a grouting pipe 4, a pressure sensor 5, and two tail shield sealing assemblies 3.

[0032] The shield tail assembly 1 includes a shield tail housing 101, a through groove 102 formed on the circumferential surface of the shield tail housing 101, an axially penetrating mounting groove 103 formed on the shield tail housing 101, and a recess 104 formed on the end face of the shield tail housing 101. There are multiple through grooves 102, mounting grooves 103, and recesses 104, and the mounting grooves 103 and recesses 104 are connected.

[0033] The sealing tube assembly 2 includes a square tube 201 and a connecting tube 202 fixed to the bottom of the square tube 201. The square tube 201 is embedded in the through groove 102 and is connected to the connecting tube 202. The connecting tube 202 passes through the through groove 102. There are multiple sealing tube assemblies 2, and each sealing tube assembly 2 is distributed at equal angles along the circumference of the shield tail shell 101.

[0034] The sealing tube assembly 2 forms the air intake and exhaust channels of the pressure balance chamber 6 and is connected to the external air passage through the connecting pipe 202. It is a key actuator for realizing active pressure management.

[0035] The sealing tube assembly 2 acts as a pressure regulating channel in this mechanism. Its connecting pipe 202 passes through the through-slot 102 and is connected to an external air source, such as a compressed air pump. When the pressure sensor 5 detects insufficient pressure in the pressure balancing chamber 6, the external air source injects gas into the chamber through the connecting pipe 202 and the square tube 201 to increase the pressure; conversely, pressure can be controlled to be released through this passage. This process ensures that the pressure in the pressure balancing chamber 6 is always dynamically balanced with the external formation and grouting pressure.

[0036] The tail shield sealing assembly 3 includes two tail shield sealing brushes 301 and a grease chamber 302 located between the two tail shield sealing brushes 301. The pressure balance chamber 6 is a sealed space naturally formed by the two tail shield sealing assemblies 3 after being axially installed on the tail shield shell. Its core function is "buffering" and "balancing", realizing functional synergy and hierarchical management of pressure.

[0037] The inner shield tail sealing brush 301 and grease chamber 302 form the final line of defense, achieving reliable sealing under stable pressure.

[0038] The grouting pipe 4 is embedded in the installation groove 103. The number and position of the grouting pipe 4 should match the installation groove 103 and the recess 104 to ensure that the grout can evenly cover the circumference of the shield tail.

[0039] The outermost grouting pipe 4 forms the first active defense line, and its function is to fill the gap at the shield tail and stabilize the strata as soon as possible.

[0040] The pressure sensor 5 is fixedly mounted on the tail shield housing 101 and located within the pressure balancing chamber 6. The pressure sensor 5 should be connected to the central control system of the TBM to achieve real-time data processing and automatic adjustment. The pressure balancing chamber 6 is a sealed space formed by two tail shield sealing assemblies 3 isolated in the axial direction. Its shape and size can be optimized according to the tail shield diameter to enhance the pressure response speed.

[0041] By arranging the grouting pipe 4, pressure balancing chamber 6, and shield tail sealing assembly 3 in a specific spatial sequence, and utilizing the air pressure sensor 5 and sealing pipe assembly 2 as nerves and blood vessels, a deep synergy in timing and efficiency of the three major functions of "grouting, balancing, and sealing" is achieved, thus forming an intelligent and efficient organic whole.

[0042] During the TBM tunneling process, the various components of this device work together in accordance with the following process:

[0043] Simultaneous grouting: While the TBM is tunneling, grout is injected through grouting pipes 4 distributed along the circumference. The grouting pipes 4 are embedded in the installation grooves 103 and, through the communication structure with the grooves 104, the grout is evenly filled into the gap between the shield tail and the tunnel segments to form the first layer of support and initially establish the external pressure environment.

[0044] Pressure Balancing: Grouting pressure, soil pressure, and water pressure in the soft soil layer act on the shield tail. At this time, the pressure balancing chamber 6 plays a crucial role as a buffer zone. The air pressure sensor 5 continuously monitors its internal pressure. Based on sensor feedback, the TBM's control system actively injects or expels gas into the pressure balancing chamber 6 by controlling the external air supply system connected to the sealing pipe assembly 2, precisely maintaining stable pressure within the chamber. This process effectively isolates drastic fluctuations in external pressure, creating stable working conditions for the internal sealing system.

[0045] Tail seal: Under the effective protection of the pressure balance chamber 6, the two inner tail seal assemblies 3 operate under optimal conditions. A grease injection system (not shown in the figure), a standard configuration in the field, continuously supplies sealing grease to the grease chamber 302. The grease fills the space between the two tail seal brushes 301, forming a flexible and tight final sealing barrier, completely preventing mud and water from entering the tunnel boring machine.

[0046] The preferred embodiments of this utility model disclosed above are merely illustrative of the present utility model. These preferred embodiments do not exhaustively describe all details, nor do they limit the utility model to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of this utility model, thereby enabling those skilled in the art to better understand and utilize it. This utility model is limited only by the claims and their full scope and equivalents.

Claims

1. An integrated device for TBM tail sealing and synchronous grouting in soft soil layers, characterized in that, include: The shield tail assembly (1) includes a shield tail housing (101), a through groove (102) formed on the circumferential surface of the shield tail housing (101), an axially penetrating mounting groove (103) formed on the shield tail housing (101), and a groove (104) formed on the end face of the shield tail housing (101). A sealing tube assembly (2) includes a square tube (201) and a connecting tube (202) fixed to the bottom of the square tube (201), wherein the square tube (201) is embedded in a through groove (102); Grouting pipe (4), which is embedded in the mounting groove (103); Two shield tail sealing assemblies (3), each shield tail sealing assembly (3) includes two shield tail sealing brushes (301) and a grease chamber (302) located between the two shield tail sealing brushes (301). The two shield tail sealing assemblies (3) are disposed on the shield tail housing (101) and form a pressure balance chamber (6). A pressure sensor (5) is fixedly installed on the tail shell (101) and located in the pressure balance chamber (6).

2. The integrated device for TBM tail sealing and synchronous grouting in soft soil as described in claim 1, characterized in that, The number of the through groove (102), the mounting groove (103) and the recess (104) are all multiple, and the mounting groove (103) and the recess (104) are connected.

3. The integrated device for TBM tail sealing and synchronous grouting in soft soil as described in claim 1, characterized in that, The connecting pipe (202) passes through the through groove (102).

4. The integrated device for TBM tail sealing and synchronous grouting in soft soil as described in claim 1, characterized in that, The number of sealing tube assemblies (2) is multiple, and each sealing tube assembly (2) is distributed at equal angles along the circumference of the shield tail shell (101).

5. The integrated device for TBM tail sealing and synchronous grouting in soft soil as described in claim 1, characterized in that, The square tube (201) is connected to the connecting tube (202).

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