Self-sealing segment structure, segment sealing ring and construction method

Abstract

The present disclosure relates to a self-sealing segment structure, a segment closing ring and a construction method. The self-sealing segment structure includes: a segment body, which is an arc-shaped structure, which has an outer arc surface and an inner arc surface in the radial direction, and a first side and a second side in the axial direction; a slurry bag, which is arranged on the outer arc surface and biased to the first side or the second side, and its length and direction are consistent with the outer arc surface, and its two sides are sealed and fixed on the outer arc surface; a grouting pipe, which is pre-buried in the segment body, one end of which extends to the inner arc surface, and the other end extends to the outer arc surface and faces the slurry bag; a first slurry bag protection part, which is arranged on the outer arc surface and completely covers the slurry bag from the outside, and its two sides are connected to the outer arc surface, and can be squeezed by the slurry bag during the grouting expansion process and separated from the segment body. The segment structure proposed in the present disclosure can be spliced ​​end to end to form a segment closing ring to stabilize the surrounding segments, and can form a closed interval in the unit area to avoid slurry leakage during grouting and improve the quality of the backfill body.

Description

Technical Field

[0001] The present disclosure relates to the technical field of tunnel construction, in particular to a tunnel segment under construction, and specifically to a self-sealing tunnel segment structure, a tunnel segment sealing ring, and a construction method. Background Art

[0002] With the advancement of mechanization in tunnel construction in China, more and more tunnel boring machines (TBMs) are being used in tunnel excavation. As tunnel construction in China expands, tunnel construction is becoming increasingly complex. As tunnel length and depth increase, geological and hydrological conditions become more complex and difficult to monitor. Against this backdrop, TBMs offer a range of advantages over traditional construction methods, including high excavation efficiency, improved economic benefits, superior lining integrity, and enhanced safety, leading to their widespread application.

[0003] The TBM's operating principle is that the front shield, driven by a propulsion cylinder, rotates through the front cutterhead to cut rock, causing it to break and dislodge. TBMs are primarily categorized as open TBMs, single-shield TBMs, and double-shield TBMs. Double-shield TBMs are the most commonly used, with a workflow consisting of three stages: tunneling, segment support, and pea gravel backfill grouting. The pea gravel grouting layer formed during the pea gravel backfill grouting, combined with the segment support, determines the overall safety and waterproofing of the support structure, a crucial factor influencing the tunnel's ultimate quality.

[0004] The status of each ring segment under the actual working conditions of TBM backfill grouting is as follows Figure 1 As shown in the figure, the main problems of pea gravel backfill grouting in actual engineering applications are as follows:

[0005] (1) See Figures 2 to 4 , pea gravel itself contains a lot of stone powder, and the filling pressure is relatively high. The collision between pea gravel and the collision between pea gravel and rock wall also leads to the generation of stone powder. In addition, the high-pressure and high-speed air will cause a large amount of stone powder and dust to enter the tunnel, affecting the field of vision, endangering the health of workers, and affecting the timely discovery and inspection of safety hazards. Although the backward shift of the pea gravel filling segment position can improve the above problems, it also brings new problems. The most important one is that the backward shift of the pea gravel filling position causes the segment to fall out of the shield tail. Although there are pads (mainly wood, some projects use prefabricated bottom ring segments with raised bottoms) placed under the segment to provide support, the large-diameter reinforced concrete segment has a large deadweight, the wooden pads have low compressive strength, and the deformation is large. The segment lacks vertical support and is almost in a suspended state, which can easily lead to vertical displacement of the segment, misalignment, breakage, water leakage and other problems.

[0006] (2) See Figure 5The pea gravel backfill grouting part is in an unsealed open area, and there is no seal between the grouting area and the blown fill area. The unsealed area causes the slurry poured in the grouting area to flow into the blown fill area, and it is difficult to maintain a reasonable slurry pressure in the grouting area according to the construction design. The slurry is in a low-pressure or even no-pressure environment for a long time in the grouting interval, and can only rely on the fluidity of the slurry itself to penetrate between the pea gravel gaps. The grouting and filling effect is poor, and it is easy to cause filling gaps, so that the final pea gravel backfill grouting body has serious defects such as pure cement slurry, partial voids, loose grouting filling, and pure pea gravel.

[0007] Therefore, it is necessary to propose a new segment structure. The closed ring formed by splicing the new segment structure can play a good role in sealing the unit area and avoid the occurrence of the above problems. Summary of the Invention

[0008] In view of the deficiencies in the prior art, the main purpose of the present disclosure is to provide a self-sealing segment structure, a segment sealing ring and a construction method to solve one or more problems in the prior art.

[0009] The technical solutions disclosed in this disclosure are as follows:

[0010] A first aspect of the present disclosure provides a self-sealing segment structure, comprising:

[0011] The segment body is an arc-shaped structure having an outer arc surface and an inner arc surface in the radial direction and a first side and a second side in the axial direction;

[0012] a pulp bag, arranged on the outer arc surface of the tube segment body and biased toward the first side or the second side, with its length and direction consistent with the outer arc surface, and with both sides sealed and fixed on the outer arc surface;

[0013] A grouting pipe is pre-buried in the segment body, one end of which extends to the inner arc surface of the segment body, and the other end extends to the outer arc surface and faces the grouting bag;

[0014] The first pulp sac protection portion is arranged on the outer arc surface of the tube segment body and completely covers the pulp sac from the outside. Its two sides are connected to the outer arc surface and can be squeezed by the pulp sac during the grouting and expansion process of the pulp sac and separated from the tube segment body.

[0015] The present invention improves the existing segment structure to form a self-sealing segment structure. By grouting the slurry bag, the segment closed ring can establish a segment surrounding rock support system on all sides, which can stabilize the segment ring. After grouting, the slurry bag of the self-sealing segment structure can fill the gap between adjacent segments and the rock mass, avoiding slurry leakage during pea gravel backfill grouting and subsequent segment misalignment, segment damage, and segment water leakage. The slurry bag arrangement can be pre-made at the segment prefabrication site and used directly on site, or it can be temporarily installed at the construction site. It is flexible in form, simple to construct, and has good practicality.

[0016] In some embodiments, the pulp bladder is a rubber pulp bladder made of three layers of nitrile rubber sandwiched between two layers of nylon cloth, with a maximum pressure bearing capacity of 5 bar.

[0017] In some embodiments, the pulp sac is symmetrically folded on the outer arc surface of the tube segment body, and the two sides of the pulp sac are fixed by a sealing mechanism. The sealing mechanism on each side includes a bolt and a pressure plate. The pressure plate is pressed onto the upper surface of the pulp sac, and the bolt passes through the pressure plate and is fixed to the tube segment body.

[0018] In some embodiments, the sealing mechanism on each side further includes a smooth circular pressure rib, two smooth circular pressure ribs are provided, and the two smooth circular pressure ribs are respectively arranged on both sides of the bolt and between the pressure plate and the pulp bag, and the pressure plate is pressed against the upper surface of the pulp bag.

[0019] In some embodiments, the bolts and the pressure plates are evenly spaced along the length of the pulp sac, and the smooth circular pressure ribs are arranged throughout the entire length, with a length consistent with the length of the pulp sac.

[0020] In some embodiments, the self-sealing tube sheet structure further includes a second pulp sac protection portion, which is disposed along the length direction of the pulp sac on both sides of the pulp sac and between the sealing mechanism and the pulp sac.

[0021] In some embodiments, the second pulp sac protection portion is a protective rubber having an arc-shaped cross section with the arc surface concave toward one side of the pulp sac, and its lower portion is pressed against the upper surface of the pulp sac and fixed to the tube body.

[0022] In some embodiments, the first pulp sac protection portion is a PA plate, the cross section of which is semi-elliptical, and both sides are glued to the tube body.

[0023] Another aspect of the present disclosure provides a segment sealing ring. This ring is formed by splicing the self-sealing segment structures of the first aspect of the present disclosure end-to-end, with the grout pockets of adjacent self-sealing segment structures staggered. The segment sealing ring effectively seals the unit area, facilitates grouting, and improves backfill quality. This ring structure allows for non-stop construction, resulting in short construction time, low cost, high safety, and effective grouting control.

[0024] In another aspect, the present disclosure provides a method for constructing a segment sealing ring, comprising:

[0025] S1: 3 rings of pea gravel filled after the ordinary segment is separated from the shield tail;

[0026] S2: Assemble the self-sealing segment structure every 20 rings to form a closed segment ring;

[0027] S3: Grouting is performed on the slurry bags on the self-sealing segments of the segment sealing ring. The slurry bags expand and press tightly between the segment body and the surrounding rock. The slurry bags on adjacent self-sealing segments overlap end to end, forming an annular closed area between the outer periphery of the segment sealing ring and the surrounding rock.

[0028] S4: Grout filling is carried out in the annular closed area to establish permanent support.

[0029] The beneficial effects of the present disclosure over the prior art are as follows: the self-sealing segment structure proposed in the present disclosure can form a segment closed ring by splicing the end to end of adjacent self-sealing segment structures in a staggered manner. By grouting the slurry sacs of the self-sealing segment structure, a segment closed ring and the surrounding rock can establish a segment slurry sac surrounding rock support system, which can stabilize the ring segment and prevent large-scale posture deviation of the segment. The segment closed ring can also play a good role in sealing the unit area, facilitate grouting, and improve backfill quality. The self-sealing segment structure perfectly solves the contradiction between the excavation efficiency and the segment bean gravel backfill grouting process, and achieves the construction of a closed ring structure without stopping the machine, with short construction time, low cost, high safety, and good grouting effect. Specifically, it also has at least the following practical effects:

[0030] The slurry bladder is a rubber slurry bladder made of three layers of nitrile rubber and two layers of nylon cloth to increase the pressure and thickness. It is wear-resistant and heat-resistant, with a maximum pressure of 5 bar, and can cope with variable grouting pressure and various complex geological environments.

[0031] The first slurry bag protection part is glued to the pipe segment body with glue, which can protect the integrity of the structure during transportation. At the same time, after the slurry bag is grouting and expanding, it can prevent the protrusions on the surrounding rock from causing damage to the slurry bag.

[0032] The second pulp sac protection portion is arranged between the sealing mechanism and the pulp sac, and mainly plays the role of protecting the pulp sac, preventing the pulp sac from being damaged during transportation and being damaged by the sealing mechanism during the pulp sac grouting process.

[0033] It should be understood that the implementation of any embodiment of the present disclosure does not mean that multiple or all of the above-mentioned beneficial effects must be possessed or achieved at the same time.

[0034] It should be understood that the contents described in the Summary of the Invention section are not intended to limit the key or important features of the embodiments of the present disclosure, nor are they intended to limit the scope of the present disclosure. Other features of the present disclosure will become readily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] To more clearly illustrate the embodiments of the present disclosure or the technical solutions in the prior art, the following briefly introduces the drawings required for the embodiments or the description of the prior art. Obviously, the drawings described below are merely illustrative, and those skilled in the art can derive other implementation drawings based on the provided drawings without inventive effort.

[0036] The structures, proportions, sizes, etc. illustrated are only used to match the contents disclosed in the specification so as to facilitate understanding and reading by persons familiar with the art. They are not intended to limit the conditions under which the present disclosure can be implemented and therefore have no substantive technical significance. Any structural modifications, changes in proportions, or adjustments in sizes shall still fall within the scope of the technical contents disclosed in the present disclosure without affecting the efficacy and objectives that can be achieved by the present disclosure.

[0037] Figure 1 This is a schematic diagram of the status of each ring under actual working conditions of backfill grouting of the existing double-shield TBM;

[0038] Figure 2 This is a diagram showing the segment misalignment problem in a conventional tunnel.

[0039] Figure 3 This is a diagram showing a segment damage problem in a conventional tunnel;

[0040] Figure 4 This is a diagram showing the segment leakage problem in a conventional tunnel;

[0041] Figure 5 This is a diagram showing the void problem that occurred during pea gravel backfill grouting in a conventional tunnel section.

[0042] Figure 6 A cross-sectional view of a self-sealing segment structure according to an embodiment of the present disclosure;

[0043] Figure 7A top view of a self-sealing segment structure according to an embodiment of the present disclosure;

[0044] Figure 8 This is a schematic diagram of a self-sealing segment structure according to an embodiment of the present disclosure;

[0045] Figure 9 Schematic diagram of the splicing of a self-sealing pipe structure and adjacent self-sealing pipe segment structures according to an embodiment of the present disclosure, wherein (a) is before sac grouting, and (b) is after sac grouting;

[0046] Figure 10 This is a schematic diagram of the segment closed ring structure after the self-sealing segment structure is assembled;

[0047] Figure 11 This is the flow chart for the segment closed loop construction;

[0048] Figure 12 This is a cross-sectional diagram of the completed construction status of the segment closure ring. DETAILED DESCRIPTION

[0049] In order to make the purpose, technical solutions and advantages of the embodiments of the present disclosure more clear, the embodiments of the present disclosure are further described in detail below in conjunction with the embodiments and drawings. Here, the illustrative embodiments of the present disclosure and their descriptions are used to explain the present disclosure, but are not intended to limit the present disclosure.

[0050] In this disclosure, unless otherwise expressly specified or limited, terms such as "mounted," "connected," "connect," and "fixed" should be understood broadly. For example, they may refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components or interactions between two components. Those skilled in the art will understand the specific meanings of these terms in this disclosure based on specific circumstances.

[0051] It should be understood that the terms "comprises / comprising," "consisting of," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a product, apparatus, process, or method that includes a list of elements includes not only those elements but also, if necessary, other elements not explicitly listed, or elements inherent to such product, apparatus, process, or method. In the absence of further limitations, elements defined by the phrases "comprises / comprising," "consisting of," do not preclude the presence of additional identical elements in the product, apparatus, process, or method that includes the elements.

[0052] It is also necessary to understand that terms such as "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", and "outside" indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present disclosure and simplifying the description, and do not indicate or imply that the device, component or structure referred to must have a specific direction, be constructed or operate in a specific direction, and should not be understood as a limitation on the present disclosure.

[0053] There are two common types of closed rings (or grouting stems). The first type is to inject quick-setting cement slurry between the segments and the rock mass every 40-60m to form a closed space between areas. However, in the actual construction process, it is difficult to form an effective closed ring that can prevent the slurry from flowing between areas by injecting liquid in the gaps where there is no axial support. The second type is to manually construct a cement closed ring after the shield tail is removed. That is, the TBM is stopped when the segment is separated from the segment, and workers construct a cement seal at the joint between the segment and the TBM. The closed ring constructed by this method has a complete structure and a good grouting effect, but it is manpower-consuming and costly. The TBM suspends excavation during construction, which is time-consuming and costly. In addition, the construction workers are in the unsupported area between the shield tail and the segment, which is very dangerous.

[0054] The self-sealing segment structure proposed in the present disclosure and the slurry bladders of adjacent self-sealing segment structures are staggered and spliced ​​end to end to form a segment closed loop. By grouting the slurry bladders of the self-sealing segment structure, the segment closed loop can establish a segment surrounding rock support system on all sides, thereby stabilizing the segment ring. Furthermore, after grouting, the slurry bladders of the self-sealing segment structure can fill the gaps between adjacent segments and the rock mass, thus avoiding slurry leakage during pea gravel backfill grouting, as well as subsequent segment misalignment, segment damage, and segment water leakage.

[0055] The implementation of the present disclosure is described in detail below in conjunction with preferred embodiments.

[0056] The self-sealing tube segment structure proposed in this disclosure is as follows: Figures 6 to 8 As shown, it includes a segment body 1, a pulp bag 2, a grouting pipe 3 and a first pulp bag protection part 4.

[0057] See also Figure 7 、 Figure 8 The segment body 1 is an arc-shaped structure. The segment body 1 has an outer arc surface and an inner arc surface in the radial direction, and the segment body 1 has a first side and a second side in the axial direction.

[0058] The first side and the second side mentioned in the present disclosure are merely orientation indications, and refer to the left and right sides or both sides of the axial direction of the segment body 1 .

[0059] Continue to see Figure 7 、 Figure 8The pulp bag 2 is arranged on the outer arc surface of the tube segment body 1 and is biased towards the first side or the second side. Its length and direction are consistent with the outer arc surface of the tube segment body 1, and both sides are sealed and fixed on the outer arc surface of the tube segment body 1.

[0060] It should be understood that the length and direction of the pulp bag 2 mentioned here are consistent with the outer arc surface of the segment body 1. The pulp bag 2 is arranged on one side of the segment body 1 along the length direction of the outer arc surface of the segment body 1. That is to say, the length of the pulp bag 2 is at least consistent with the length of the segment body 1, so that the pulp bag 2 can be completely filled into the gap between the segment and the rock mass after grouting, and fully cover the entire length range of the segment.

[0061] The pulp bag 2 is arranged on the outer arc surface of the tube segment body 1, biased towards the first side or the second side, rather than being arranged on the full width or in the center of the outer arc surface of the tube segment body 1. This is to ensure that when the self-sealing tube segment structure is spliced ​​end to end with the adjacent self-sealing tube segment structure, the pulp bag 2 on the self-sealing tube segment structure can be staggered and overlapped after grouting, completely filling the gap between the adjacent self-sealing tube segment structures, thereby ensuring the sealing of the joint.

[0062] The grouting pipe 3 is pre-buried in the segment body 1 , with one end of the grouting pipe 3 extending to the inner arc surface of the segment body 1 , and the other end extending to the outer arc surface of the segment body 1 and facing the slurry bag 2 .

[0063] The first sac protection part 4 is arranged on the outer arc surface of the tube segment body 1 and completely covers the outside of the sac 2. The two sides of the first sac protection part 4 are connected to the outer arc surface of the tube segment body 1, and can be squeezed by the sac 2 during the grouting process of the sac 2 and separated from the tube segment body 1.

[0064] It is easy to understand that the first slurry bag protection part 4 is squeezed by the slurry bag 2 during the grouting process and can be separated from the pipe segment body 1 in order to ensure that the slurry bag 2 can extend to the adjacent self-sealing pipe segment structure after grouting, fill the gap between the adjacent self-sealing pipe segment structures, and prevent the occurrence of slurry leakage and channeling.

[0065] In some embodiments, the segment body 1 can be a precast concrete segment structure or a steel segment structure, and the precast concrete segment structure is preferred herein.

[0066] It should be understood that the size of the precast concrete segment structure should correspond to the size of the tunnel during actual construction, and no specific limitation is made herein.

[0067] In some embodiments, the slurry bag 2 is a rubber slurry bag, preferably made of three layers of nitrile rubber and two layers of nylon cloth to form a high-pressure thick slurry bag, which is wear-resistant and heat-resistant, and can withstand a maximum pressure of 5 bar. It can cope with variable grouting pressure and various complex geological environments.

[0068] In some embodiments, the grouting pipe 3 is a 100 mm diameter grouting pipe. The grouting pipe 3 should be designed and pre-buried within the segment body 1 according to the size and position of the segment body 1 to ensure stability during subsequent grouting of the slurry bag 2. The grouting pipe 3 can be pre-buried during the segment production process or installed on-site by drilling holes into the existing segment structure.

[0069] In some embodiments, the slurry bag 2 is symmetrically folded on the outer arc surface of the segment body 1. This arrangement can save space and ensure that the slurry bag 2 can simultaneously fill the gap between the segments and rock masses of adjacent rings after grouting.

[0070] Preferably, both sides of the pulp bag 2 are fixed by a sealing mechanism, and the sealing mechanism completely fixes both sides of the pulp bag 2 on the outer arc surface of the segment body 1 to ensure that the pulp bag 2 does not leak slurry after grouting.

[0071] In some embodiments, the sealing mechanism on each side of the pulp sac 2 includes a bolt 5 and a pressure plate 6. The pressure plate 6 is directly pressed onto the upper surface of the pulp sac 2. The bolt 5 passes through the pressure plate 6 and is fixed to the tube body 1. The edges of both sides of the pulp sac 2 are sealed by the pressure plate 6.

[0072] Preferably, a plurality of bolts 5 are provided on each side of the pulp sac 2 , which are evenly arranged along the length direction of the pulp sac 2 at a certain distance, and the bolts 5 on both sides of the pulp sac 2 correspond one to one.

[0073] Preferably, the pressing plates 6 can be evenly spaced on both sides of the pulp sac 2 along the length direction of the pulp sac 2, or can be arranged along the length direction of the pulp sac 2.

[0074] It should be understood that the "multiple" here can be three, four, or more, and the specific number is not limited herein, as long as it can ensure that both sides of the pulp sac 2 are completely sealed and fixed.

[0075] Preferably, the bolts 5 are hexagonal bolts with a size of Φ22. Laboratory tests have shown that the Φ22 hexagonal bolts have little effect on the stress of the segment body 1. The embedded bolts 5 will not affect the life, safety and waterproofness of the self-sealing segment structure. At the same time, the Φ22 hexagonal bolts can meet the pressure required for the fixing device. The use of hexagonal bolts ensures the versatility of the device installation tools and high installation efficiency.

[0076] Preferably, the pressing plate 6 is a 20 mm thick steel pressing plate. Laboratory tests have shown that 20 mm is the most suitable thickness for a steel pressing plate while ensuring pressure transmission effect, which can reduce weight and save costs.

[0077] The pressing plate 6 applies the point pressure of the bolt 5 evenly to the upper surface of the pulp bag 2 to ensure the sealing effect of the pulp bag 2.

[0078] In some embodiments, the sealing mechanism on each side further includes a pressure rib 7. Preferably, two pressure ribs 7 are provided, and the two pressure ribs 7 are respectively arranged on both sides of the bolt 5, and the pressure ribs 7 are located between the pressure plate 6 and the pulp bag 2, and are pressed against the upper surface of the pulp bag 2 by the pressure plate 6.

[0079] In some embodiments, the ribs 7 are preferably smooth round ribs, which are arranged along the entire length of both sides of the pulp sac 2 , and the length of the smooth round ribs is consistent with the length of the pulp sac 2 .

[0080] It should be understood that the double compression ribs 7 are arranged on both sides of the bolts 5 arranged along the length direction of the pulp bag 2. Under the action of the pressure plate 6, the pulp bag 2 is pressed against the tube body 1 to reduce the gap between the two and achieve sealing between different materials.

[0081] Preferably, the embossing rib 7 is a smooth round embossing rib with a size of Φ20.

[0082] In some embodiments, the self-sealing tube sheet structure further includes a second pulp sac protection portion 8, which is arranged along the length direction of the pulp sac 2. The second pulp sac protection portion 8 is arranged on both sides of the pulp sac 2, between the sealing mechanism and the pulp sac 2.

[0083] It should be understood that the second pulp sac protecting portion 8 mainly serves to protect the pulp sac 2 from both sides, preventing the pulp sac 2 from being damaged during transportation and being damaged by the sealing mechanism during the pulping process.

[0084] Preferably, the second sac protection portion 8 is a protective rubber having an arc-shaped cross section with the arc surface concave toward the side of the sac 2 , and its lower portion is pressed against the upper surface of the sac 2 and fixed to the tube body 1 by bolts 5 .

[0085] Preferably, the protective rubber is made of wear-resistant thick rubber, the rubber has a certain elasticity, and the surface is coated with a lubricant, such as butter, which not only protects the pulp bag 2, but also can extend outward together with the pulp bag 2 after grouting.

[0086] It should be understood that the protective rubber here is arranged in an arc shape and the arc surface is concave toward one side of the pulp sac 2. In the natural state, it is like two hands wrapping around the pulp sac 2 from both sides to protect the two sides of the pulp sac from damage. After the pulp sac 2 is grouted and expanded, the two sides of the pulp sac 2 can be completely fitted with the protective rubber. As the pulp sac 2 expands and squeezes outward, the pulp sac 2 extends outward in both length and width directions. The protective rubber can isolate the pipe segment and the pulp sac 2. At the same time, the lubricant on its surface can reduce the resistance encountered by the pulp sac 2 during grouting and expansion when symmetrically folded.

[0087] In some embodiments, the first sac protection portion 4 is a PA plate with a semi-elliptical cross-section, with both sides glued to the segment body 1. The semi-elliptical design can completely enclose the sac 2 from the outside and reduce friction between the sac 2 and the first sac protection portion 4 during grouting and expansion.

[0088] The PA board has good wear resistance and is scratch and puncture resistant. Use glue to stick the two ends of the PA board that wraps the entire pulp bag 2 to the outside of the pipe segment body 1, which can protect the integrity of the device during transportation. At the same time, the pulp bag 2 can fall off under a predetermined pressure after grouting and expansion. Pressing the PA board on the surrounding rock can prevent the protrusions on the surrounding rock from damaging the pulp bag 2.

[0089] Preferably, the glue here should be pollution-free, have moderate fluidity, and have a short solidification time. It must also be able to fall off naturally during the grouting expansion process of the slurry bag 2 to release the connection between the PA plate and the pipe segment body 1.

[0090] It should be understood that the glue here does not permanently adhere the ends of the PA sheet to the segment body 1. Instead, it adheres the PA sheet to the outer curved surface of the segment body 1 during transportation of the self-sealing segment structure, ensuring the integrity of the self-sealing segment structure during transportation. The glue also needs to be able to fall off during the grouting and expansion of the slurry bladder 2, releasing the connection between the PA sheet and the segment body 1. This ensures that after grouting and expansion, the slurry bladder 2 can extend outward to the adjacent segment, filling the gap between adjacent segments and ensuring the sealing of the joint.

[0091] In some embodiments, a grouting port 9 is provided at one end of the grouting pipe 3 extending outward from the inner arc surface of the segment body 1. It should be understood that the grouting port 9 is provided on one side of the inner arc surface of the segment body 1 to facilitate installation and removal.

[0092] Preferably, the grouting port 9 is an integrated intelligent grouting port, which is integrated with a pressure sensor, a safety valve, and a plug. The integrated intelligent grouting port can ensure the safety and reliability of the grouting process, and can also monitor the slurry pressure in the slurry bag 2 in real time, adjust the grouting amount in time, and solve the problem of inaccurate slurry pressure monitoring in the grouting pipeline.

[0093] The self-sealing segment structure does not require redoing the mold. It only requires burying a pair of Φ22 hexagonal bolts with a certain horizontal spacing at regular intervals vertically on the original normal segment, i.e., the segment body 1, and reserving grouting pipes 3 and grouting ports 9 on the segment body 1. High-pressure rubber slurry bags are respectively inserted into the two rows of bolts 5, and the slurry bags 2 are folded in half between the two rows of bolts 5. A wear-resistant thick rubber protective slurry bag with a cross-section approximately in the shape of a strip is placed on the outside of the slurry bag 2. A Φ20 smooth circular rib of the same length as the segment body 1 is placed outside the wear-resistant thick rubber on both sides of each row of bolts 5, and a 20mm thick steel pressing plate is used to press on the Φ20 smooth circular rib to prevent the smooth circular rib from moving. The bolts 5 are tightened with round head nuts 51 above the 20mm thick steel pressing plate. Finally, glue is used to stick the two ends of the PA plate covering the entire slurry bag 2 to the segment body 1 to protect the entire slurry bag 2 and prevent injury.

[0094] In some embodiments, see Figure 9 、 Figure 10 The self-sealing segment structure and the adjacent self-sealing segment structure are spliced ​​end to end by staggering the pulp bags 2 on the segment body 1, and the ends of the pulp bags are overlapped to form a segment closed ring.

[0095] It should be noted that Figure 8 and Figure 10 The shape of the middle segment and the slurry bag is only for illustration, the purpose of which is to show the arrangement of the slurry bags on the segment and the staggered overlap effect in the spliced ​​state. It does not limit the shape of the slurry bag and its shape after grouting expansion. The shape of the slurry bag after grouting expansion is also related to the size of the slurry bag itself, the grouting pressure and the size of the space between the segment and the surrounding rock.

[0096] It should be understood that the staggered splicing of the pulp sacs 2 here means that the pulp sacs 2 on the two adjacent tube segment bodies 1 are not arranged on the same side, but are arranged on the left and right sides of the tube segment body 1 respectively, to ensure that the pulp sacs 2 of the self-sealing tube segment structure spliced ​​together end to end can be staggered and overlapped together after the pulp sacs 2 are grouting. After the pulp sacs 2 are grouting, the mutual squeezing between the two adjacent pulp sacs 2 can completely fill the gap between the adjacent self-sealing tube segment structures, thereby ensuring the sealing of the joints.

[0097] The head and tail splicing here means that the head of the self-sealing segment structure and the tail of the self-sealing segment structure after the self-sealing segment structure is turned over are spliced ​​together; the tail of the self-sealing segment structure and the head of the self-sealing segment structure after the self-sealing segment structure is turned over are spliced ​​together.

[0098] It should be understood that the head and tail mentioned here are an orientation indication, referring to one end and the other end of each self-sealing segment structure.

[0099] After the self-sealing segment structure is assembled into a complete segment closed ring, a grouting pump is used to connect to the grouting valve nozzle of the grouting pipe 3 reserved in the segment body 1 through the grouting controller to carry out grouting, so that the high-pressure rubber slurry bag contacts the surrounding rock to establish a seal. After reaching the set grouting pressure (3 bar or higher), the grouting is stopped and the grouting device is released, and the slurry pressure value inside the slurry bag 2 is monitored at any time.

[0100] It should be understood that the grouting pump here is the grouting pump used in the TBM supporting trolley. There is no need to install a separate grouting pump, and it has good versatility.

[0101] See also Figure 11 The construction method of forming a segment closed ring with a self-sealing segment structure is as follows:

[0102] S1: 3 rings of pea gravel filled after the ordinary segment is separated from the shield tail;

[0103] S2: Assemble the self-sealing segment structure every 20 rings to form a closed segment ring;

[0104] S3: Grouting is performed on the slurry bags on the self-sealing segments of the segment sealing ring. The slurry bags expand and press tightly between the segment body and the surrounding rock. The slurry bags on adjacent self-sealing segments overlap end to end, forming an annular closed area between the outer periphery of the segment sealing ring and the surrounding rock.

[0105] S4: Grout filling is carried out in the annular closed area to establish permanent support.

[0106] like Figure 12 The entire ring of pre-buried slurry bag segments that have completed grouting establishes a segment slurry bag surrounding rock support system through the slurry bag 2 and the surrounding rock, which can stabilize the ring segments and stabilize the segment group within the 20 rings through the fixed structure between the rings, preventing large-scale posture deviation of the segments.

[0107] The constructed segment sealing ring can also play a good role in sealing the unit area. The pea gravel backfill grouting in the closed section ensures that the pressure of the pea gravel backfill grouting in the area is uniform, prevents slurry leakage and channeling, ensures the pea gravel backfill grouting effect at the top of the segment sealing ring, and improves the quality of the backfill body. The segment sealing ring formed at the same time perfectly solves the construction contradiction between the excavation efficiency and the segment pea gravel backfill grouting process, and achieves the construction of the segment sealing ring structure without stopping the machine, with short construction time, low cost, high safety, and good grouting effect. The present disclosure is particularly suitable for TBM tunnel construction. The segment sealing ring is the same size as the TBM tunnel. Each ring of the segment sealing ring includes multiple concrete segments, for example, four segments. The four concrete segments can be the same or different. For example, the upper and lower segments are the same size and larger, and the left and right segments are the same size and smaller, depending on the design requirements of the tunnel construction and the manufacturing process of the segments.

[0108] It should be understood that the present disclosure has no additional requirements for the filling slurry in the slurry bag 2 on the segment body 1. It only needs to consider injectability, appropriate setting time, and strength that meets the requirements of ordinary cement slurry.

[0109] It is easy for those skilled in the art to understand that, under the premise of no conflict, the above preferred solutions can be freely combined and superimposed.

[0110] The above description is only a preferred embodiment of the present disclosure and is not intended to limit the present disclosure. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present disclosure should be included in the scope of protection of the present disclosure.

Claims

1. A self-sealing segment structure, characterized in that: include: The segment body is an arc-shaped structure having an outer arc surface and an inner arc surface in the radial direction and a first side and a second side in the axial direction; a pulp bag, arranged on the outer arc surface of the segment body and deviating toward the first side or the second side, with its length and direction consistent with the outer arc surface, and its two sides sealed and fixed to the outer arc surface by a sealing mechanism; A grouting pipe is pre-buried in the segment body, one end of which extends to the inner arc surface of the segment body, and the other end extends to the outer arc surface and faces the grouting bag; A first sac protection portion is provided on the outer curved surface of the segment body and completely covers the sac from the outside. Both sides of the first sac protection portion are connected to the outer curved surface and can be separated from the segment body by being squeezed by the sac during the grouting and expansion process of the sac. The first sac protection portion is a PA plate having a semi-elliptical cross-section and having both sides glued to the segment body. The second pulp sac protection part is provided on both sides of the pulp sac along the length direction of the pulp sac and is located between the sealing mechanism and the pulp sac; the second pulp sac protection part is a protective rubber, the cross section of the protective rubber is arc-shaped, the arc surface is concave toward one side of the pulp sac, and the lower part is pressed against the upper surface of the pulp sac and fixed to the tube body; and The pulp sacs on two adjacent tube segment bodies are not arranged on the same side. The pulp sac on one tube segment body is arranged on the first side of the tube segment body, and the pulp sac on the other tube segment body is arranged on the second side of the tube segment body, ensuring that the pulp sacs spliced ​​together end to end can be staggered and overlapped after grouting. After grouting, the mutual squeezing between the two adjacent tube segment bodies can completely fill the gap between the two adjacent tube segment bodies, ensuring the sealing of the joints.

2. The self-sealing segment structure according to claim 1, characterized in that: The pulp bladder is a rubber pulp bladder made of three layers of nitrile rubber sandwiched between two layers of nylon cloth, and has a maximum pressure bearing capacity of 5 bar.

3. The self-sealing segment structure according to claim 1, characterized in that: The pulp bag is symmetrically folded on the outer arc surface of the tube body. The sealing mechanism on each side includes a bolt and a pressure plate. The pressure plate is pressed on the upper surface of the pulp bag, and the bolt passes through the pressure plate and is fixed on the tube body.

4. The self-sealing segment structure according to claim 3, characterized in that: The sealing mechanism on each side also includes two smooth circular pressure ribs, which are respectively arranged on both sides of the bolt and between the pressure plate and the pulp bag, and the pressure plate is pressed against the upper surface of the pulp bag.

5. The self-sealing segment structure according to claim 4, characterized in that: The bolts and the pressing plates are evenly spaced along the length of the pulp sac, and the smooth round pressing ribs are arranged throughout the length, with the length being consistent with the length of the pulp sac.

6. A segment sealing ring, characterized in that: The segment sealing ring is formed by splicing the self-sealing segment structure according to any one of claims 1 to 5 end to end in a manner that the pulp sacs of adjacent self-sealing segment structures are staggered.

7. A method for constructing a segmental closed ring according to claim 6, characterized in that: include: S1: 3 rings of pea gravel filled after the ordinary segment is separated from the shield tail; S2: Assemble the self-sealing segment structure every 20 rings to form a closed segment ring; S3: Grouting is performed on the slurry bags on the self-sealing segments of the segment sealing ring. The slurry bags expand and press tightly between the segment body and the surrounding rock. The slurry bags on adjacent self-sealing segments overlap end to end, forming an annular closed area between the outer periphery of the segment sealing ring and the surrounding rock. S4: Grout filling is carried out in the annular closed area to establish permanent support.

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