Safety emergency device for preventing water leakage from a shield tail
By installing a rubber airbag inflatable sealing structure on the inside of the shield tail of the tunnel boring machine, the problem of shield tail leakage was solved, enabling rapid emergency response and safe construction, and avoiding the defects of traditional methods.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- 中国水利水电第七工程局有限公司
- Filing Date
- 2025-09-15
- Publication Date
- 2026-07-10
AI Technical Summary
In water conservancy and hydropower projects, water and sand can easily flow into the gap between the shield tail and the tunnel segments during the tunneling process of the tunnel boring machine. Existing sealing measures, such as the shield tail brush, cannot be dealt with in a timely manner after wear and failure, leading to safety and quality problems.
Four independent rubber airbags are installed inside the shield tail shell. They are connected to the shield machine's air supply system through air inlet and outlet pipes. After being inflated, they expand and fill the gap between the shield tail and the segments, forming a ring-shaped sealing structure to quickly seal off leaks.
It enables rapid emergency response to shield tail leakage, avoids the disadvantages of long-term grouting and plugging, ensures construction safety and continuity, and reduces operational complexity and environmental pollution risks.
Smart Images
Figure CN224478929U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of mechanical construction technology for water conservancy engineering tunnels, and particularly relates to the field of tunnel shield excavation technology, and specifically relates to a safety emergency device for preventing water leakage at the shield tail. Background Technology
[0002] In water conservancy and hydropower projects, long-distance tunnels with complex geological conditions are often constructed using the shield tunneling method. However, due to the complexity of the engineering geology, geological exploration of the sections crossing mountains and rivers cannot be fully completed, resulting in insufficient and detailed geological data. Furthermore, improper shield operation and non-standard segment selection can lead to wear and failure of the shield tail brush during tunneling, causing significant water and sand inflow into the shield machine and resulting in major safety and quality problems. To avoid these problems, a water-leakage safety device needs to be installed at the tail of the shield.
[0003] The existing shield tail seal uses four tail brushes, which are filled with tail grease during tunneling to achieve a sealing effect. The tail brushes are composed of numerous independent steel wires, spring steel sheets, and other components. If the tail brushes are severely damaged during construction, and a large amount of sand and water flows into the gap between the shield tail and the tunnel segments, it is impossible to address the seal issue promptly. In such cases, polyurethane can only be injected to seal the leak through the pre-drilled grouting holes in the radial direction of the shield body after the tail has detached from the tunnel segments. Only after the sand and water inflow has stopped can the tail brushes be replaced. Summary of the Invention
[0004] This utility model discloses a safety emergency device for preventing water leakage at the shield tail, based on the needs of existing tunnel boring machine (TBM) equipment construction. The purpose of this utility model is to provide a safety emergency device that, when sand and water flow into the gap between the shield tail and the tunnel lining segments after the tail brush fails, can be promptly inflated through an air pipe to fill the gap between the shield tail and the tunnel lining segments, achieving a grout-stopping effect.
[0005] This utility model is achieved through the following technical solution:
[0006] A safety emergency device for preventing water leakage at the shield tail, wherein the shield tail of a shield tunnel includes an installed shield segment and a shield shell located on the outer periphery of the shield segment and moving with the shield machine, characterized in that: four independent rubber airbags are symmetrically installed around the inner side wall of the shield shell near the grout stop plate at the end of the shield tail; each rubber airbag is circumferentially attached to the inner side wall of the shield tail, and each rubber airbag is equipped with an air inlet pipe and an air outlet pipe, and each air inlet pipe is connected to the shield machine's air supply system through a valve;
[0007] The rubber material surface of the rubber airbag has uniformly arranged anti-slip textures; the rubber airbag is arranged circumferentially along the inner side wall of the end of the shield tail shell, and the front and rear ends of the rubber airbag along the moving direction of the shield tail shell are fixed by arc-shaped pressure plates and bolts; the four independent rubber airbags are connected to each other circumferentially to form a complete annular sealing structure.
[0008] Furthermore, the rubber airbag has a structure made of high-strength, pressure-resistant rubber material and double-sealed at both ends along the direction of movement of the shield tail and shield shell.
[0009] Furthermore, each rubber airbag expands after being inflated to fill the gap between the shield tail shell and the shield segment; each rubber airbag is sealed at both ends and connected to an air inlet pipe and an air outlet pipe respectively.
[0010] After each air intake pipe is connected to the rubber airbag, its outer end is installed and fixed inside the shield tail shell, and leads out to the outside of the shield tail brush set at the rear end of the shield tail shell; each air intake pipe is equipped with a valve and pressure gauge and is independently connected to the air compressor system of the tunnel boring machine.
[0011] After each air outlet pipe is connected to the rubber airbag, its outer end is installed and fixed inside the shield tail shell, and leads out to the outside of the shield tail brush set at the rear end of the shield tail shell; each air outlet pipe is equipped with a valve.
[0012] Compared with the prior art, the present invention has the following beneficial effects:
[0013] Existing methods for handling shield tail leakage involve using a tail brush and grease, without other safety and emergency measures. This invention adds a leakage prevention and safety emergency device to the traditional shield tail leakage handling method, offering significant advantages.
[0014] This utility model device offers a rapid emergency response. When the shield tail brush fails, causing sand and water to surge, the rubber airbags in the corresponding area can be inflated immediately through the pre-set inflation pipes and valves. This allows for gap sealing in a short time, effectively curbing the escalation of the danger and buying valuable time for subsequent treatment. It overcomes the shortcomings of traditional grouting and leak sealing methods, which are time-consuming.
[0015] This utility model device is convenient and efficient to operate. The air inflation pipe is pre-embedded inside the shield shell and connected to the air compressor built into the tunnel boring machine. It can be used as soon as the valve is opened. There is no need for complicated external equipment connection and debugging, which simplifies the emergency operation process and reduces the skill level requirements of the operators.
[0016] This utility model device is highly safe. It seals the tunnel by the physical expansion of a rubber airbag, avoiding the environmental pollution and potential impact on the tail shield structure that may be caused by the use of chemical grouting materials. After the tail brush is replaced, the airbag can be deflated to restore its original state without affecting the normal tunneling function of the tunnel boring machine, thus ensuring the continuity and safety of construction.
[0017] This utility model device is highly targeted, consisting of four independent areas: top, bottom, left, and right. Four sets of independent rubber airbags are evenly distributed circumferentially along the shield tunnel. Each set of airbags is interconnected end-to-end via specialized connecting clips, forming a complete annular sealing structure. It also allows for precise selection based on the actual leakage location, avoiding the resource waste and operational inconvenience that could result from overall inflation, thus achieving localized solutions to localized problems.
[0018] This utility model's rubber airbags are made of high-strength, pressure-resistant rubber material. They are fixed to the inner side of the shield tail shell using a ring-shaped pressure plate via pre-drilled bolt holes, ensuring no displacement or detachment under high pressure. The rubber airbags expand rapidly after inflation, and their outer surface is designed with anti-slip textures to tightly fill irregular gaps between the shield tail shell and the tunnel lining segments, achieving a comprehensive seal. Each rubber airbag employs a double-layer sealing process, with one end connected to a high-pressure inlet pipe for rapid inflation, and the other end equipped with an adjustable outlet pipe for pressure control and venting. Both the inlet and outlet pipes are equipped with anti-backflow valves to ensure reliable sealing.
[0019] This utility model device provides a fast, effective, and safe emergency solution for shield tail seal failure when tunneling under complex geological conditions by setting a partitioned annular air-filled safety emergency device at the shield tail. It can significantly improve the safety and reliability of shield construction and is of great significance for ensuring the smooth implementation of major projects such as water conservancy and hydropower. Attached Figure Description
[0020] Figure 1 This is a schematic cross-sectional view of a shield tunneling machine during normal excavation.
[0021] Figure 2 This is a schematic longitudinal section diagram of the normal tunneling of the shield tunneling machine of this utility model, namely... Figure 1 Sectional view of AA in the middle;
[0022] Figure 3 This is a schematic diagram of the device of this utility model without inflation, i.e. Figure 2 Enlarged view of section B in the middle;
[0023] Figure 4 This is a cross-sectional view of the device in the inflated state.
[0024] Figure 5 This is a longitudinal sectional view of the device in its inflated state, i.e. Figure 4 CC section view;
[0025] Figure 6 This is a schematic diagram of the device in the inflation state, i.e. Figure 5 Enlarged view of section D in the middle.
[0026] In the diagram, 1-1# safety emergency device, 2-1# safety emergency device air outlet pipe, 3-2# safety emergency device air inlet pipe, 4-shield segment, 5-shield tail shield shell, 6-2# safety emergency device, 7-2# safety emergency device air outlet pipe, 8-3# safety emergency device air outlet pipe, 9-3# safety emergency device, 10-3# safety emergency device air inlet pipe, 11-4# safety emergency device air outlet pipe, 12-4# safety emergency device, 13-4# safety emergency device air inlet pipe, 14-1# safety emergency device air inlet pipe, 15-shield tail brush, 16-gap between shield shell and segment. Detailed Implementation
[0027] The present invention will be further described below with reference to specific embodiments. These specific embodiments are further explanations of the principle of the present invention and are not intended to limit the present invention in any way. Any technology that is the same as or similar to the present invention does not exceed the protection scope of the present invention.
[0028] Refer to the attached diagram.
[0029] In this embodiment, the safety emergency device for preventing water leakage at the shield tail is installed on the inner surface of the shield shell 5 near the grout stop plate at the shield tail. Four sets of safety emergency devices are set up, namely upper, lower, left, and right sets; they are arranged in four areas to form a circumferential air-filled grout stop system; each set of safety emergency devices includes a rubber airbag, an air inlet pipe, and an air outlet pipe.
[0030] The rubber airbags, fitted snugly along the inner side of the shield shell 5 at the tail, are made of rubber. During inflation, the airbags expand to fill the gaps between the shield shell and the tubular segments. The rubber airbags operate independently in four zones, without interfering with each other. Each airbag is sealed at both ends circumferentially, with only inlet and outlet pipes provided. During inflation, the outlet pipe valve is closed, and air is introduced into the airbag through the inlet pipe. Inflation stops when the pressure reaches 2.0 MPa.
[0031] The intake pipe adopts The steel pipe is installed inside the tail shield shell 5. The end of the air inlet pipe is connected to the rubber airbag, and the beginning of the air inlet pipe extends out of the tail shield brush and is equipped with valves and pressure gauges. The air compressor system on the tunnel boring machine provides compressed air and is connected to the air inlet pipe for inflation.
[0032] The exhaust pipe adopts A steel pipe is installed inside the shield shell 5 at the tail of the shield. The end of the vent pipe is connected to the rubber airbag, and the beginning of the vent pipe extends outside the tail brush and is equipped with a valve. The vent pipe can expel air and water from the rubber airbag.
[0033] During tunnel boring machine (TBM) excavation, if the tail seal brush fails, significant sand and water inflow can occur, potentially damaging construction equipment and requiring emergency handling. Based on the leakage area, the corresponding emergency safety device is inflated. The inflated rubber bladder fills the gap between the tail shield shell 5 and the tunnel lining segment 4, quickly sealing the external mud leakage. After sealing, the location of the failed tail seal brush can be quickly identified and replaced. After brush replacement, the vent pipe is opened to release air, restoring the original condition, and tunneling can resume.
[0034] A certain tunnel was constructed using a slurry balance shield tunneling machine. The main body of the shield tunneling machine is about 11.8m long, the total length of the equipment is about 100m, the minimum turning radius is 350m, the cutterhead is equipped with a composite cutterhead, and the excavation diameter is 8.83m.
[0035] like Figure 1 As shown, during normal tunneling, four tail brushes (15) and a set of safety emergency devices to prevent water leakage at the tail of the shield are installed. Each set of safety emergency devices consists of four symmetrically arranged sets of devices, conveniently positioned in the four directions: top, bottom, left, and right. These are: Safety Emergency Device 1 (1), Safety Emergency Device 2 (6), Safety Emergency Device 3 (9), and Safety Emergency Device 4 (12). Each safety emergency device can be inflated independently without affecting the others.
[0036] like Figure 1 , Figure 2 , Figure 3 As shown, the safety emergency device for preventing water leakage at the shield tail is installed inside the shield shell 5 at the shield tail, in the gap 16 between the outer side of the shield segment 4 and the shield shell 5 at the shield tail, and at the tail end of the fourth shield tail brush 15.
[0037] Emergency safety device 1 is sealed at both ends. One end is connected to the end of the inlet pipe 14 of emergency safety device 1, and the other end is connected to the end of the outlet pipe 2 of emergency safety device 1. Emergency safety device 1 is made of rubber airbag and is installed inside the shield shell 5 at the tail of the shield. Both the inlet pipe 14 and the outlet pipe 2 of emergency safety device 1 are made of rubber airbag. The steel pipe is made and pre-embedded inside the shield shell 5 installed at the shield tail, passing through the shield tail brush 15.
[0038] Emergency safety device #2 (6) is sealed at both ends. One end is connected to the end of the air inlet pipe #3, and the other end is connected to the end of the air outlet pipe #7. Emergency safety device #2 (6) is made of rubber airbags and is installed inside the shield shell 5 at the tail of the shield. Both the air inlet pipe #3 and the air outlet pipe #7 of emergency safety device #2 (6) are... The steel pipe is made and pre-embedded inside the shield shell 5 installed at the shield tail, passing through the shield tail brush 15.
[0039] Emergency safety device #3 (9) is sealed at both ends. One end is connected to the end of the air inlet pipe #10, and the other end is connected to the end of the air outlet pipe #8. Emergency safety device #3 (9) is made of rubber airbags and is installed inside the shield shell 5 at the tail of the shield. Both the air inlet pipe #10 and the air outlet pipe #8 of emergency safety device #3 (9) are... The steel pipe is made and pre-embedded inside the shield shell 5 installed at the shield tail, passing through the shield tail brush 15.
[0040] Emergency safety device #4 (12) is sealed at both ends. One end is connected to the end of the air inlet pipe #13, and the other end is connected to the end of the air outlet pipe #11. Emergency safety device #4 (12) is made of a rubber airbag and is installed inside the shield shell 5 at the tail of the shield. Both the air inlet pipe #4 (13) and the air outlet pipe #3 (11) are made of rubber airbags. The steel pipe is made and pre-embedded inside the shield shell 5 installed at the shield tail, passing through the shield tail brush 15.
[0041] like Figure 4 , Figure 5 , Figure 6 As shown, when the tail brush is worn or damaged, it needs to be replaced. Compressed air is supplied by the air compressor on the tunnel boring machine and connected to the air inlet pipes 3, 10, 13, and 14 of each safety emergency device. Valves 2, 7, 8, and 11 of the safety emergency device are opened to release air, then closed. Air supply is stopped when the pressure gauges on the air inlet pipes 3, 10, 13, and 14 reach 2.0 MPa. The gap between the inner side of the tail shield shell 5 and the outer side of the tunnel segment 4 is filled by the expansion of the air inlet pipes 3, 10, 13, and 14 of the safety emergency device to achieve the effect of stopping grout and preventing leakage.
Claims
1. A safety emergency device for preventing water leakage at the shield tail, wherein the shield tail in shield tunnel construction includes pre-installed shield segments and a shield shell located around the shield segments and moving with the tunnel boring machine, characterized in that: Four independent rubber airbags are symmetrically installed around the inner wall of the shield shell near the grout stop plate at the end of the shield tail. Each rubber airbag is circumferentially attached to the inner wall of the shield tail shell. Each rubber airbag is equipped with an air inlet pipe and an air outlet pipe. Each air inlet pipe is connected to the shield machine's air supply system through a valve. The rubber material surface of the rubber airbag has uniformly arranged anti-slip textures; the rubber airbag is arranged circumferentially along the inner side wall of the end of the shield tail shell, and the front and rear ends of the rubber airbag along the moving direction of the shield tail shell are fixed by arc-shaped pressure plates and bolts; the four independent rubber airbags are connected to each other circumferentially to form a complete annular sealing structure.
2. The safety emergency device for preventing water leakage at the shield tail as described in claim 1, characterized in that: The rubber airbag has a structure made of high-strength, pressure-resistant rubber material and double-sealed at both ends along the direction of movement of the shield tail and shield shell.
3. The safety emergency device for preventing water leakage at the shield tail as described in claim 2, characterized in that: Each rubber airbag expands after being inflated to fill the gap between the shield tail and the shield segment; each rubber airbag is sealed at both ends and connected to an air inlet pipe and an air outlet pipe respectively.
4. The safety emergency device for preventing water leakage at the shield tail as described in claim 2, characterized in that: After each air inlet pipe is connected to the rubber airbag, its outer end is installed and fixed inside the shield shell at the tail of the shield, and leads out to the outside of the shield tail brush set at the rear end of the shield shell; each air inlet pipe is equipped with a valve and pressure gauge and is independently connected to the air compressor system of the tunnel boring machine.
5. The safety emergency device for preventing water leakage at the shield tail as described in claim 2, characterized in that: After each air outlet pipe is connected to the rubber airbag, its outer end is installed and fixed inside the shield tail shell, and leads out to the outside of the shield tail brush set at the rear end of the shield tail shell; each air outlet pipe is equipped with a valve.