Concrete supporting equipment and method for short-distance subway shield to pass through operating tunnel

Abstract

The invention relates to the field of shield construction, in particular to concrete supporting equipment and method for a short-distance subway shield to penetrate through an operation tunnel, the concrete supporting equipment comprises a tunnel segment, and a plurality of grouting supporting assemblies are arranged on the tunnel segment; the grouting supporting assembly comprises a hollow pipe body, an injection opening communicated with the hollow pipe body is formed in the inner side of the tunnel segment, a plurality of telescopic partition plates are arranged on the hollow pipe body, the telescopic partition plates are provided with elastic pieces used for driving the telescopic partition plates to stretch, ferromagnetic metal sheets are fixedly connected to the telescopic partition plates, and a plurality of release openings are formed in the hollow pipe body. The release ports are located between the telescopic partition plates; the device further comprises a probing rod, the probing rod is detachably connected with the injection opening in a clamped mode, and a plurality of electromagnets are arranged in the probing rod and used for attracting the ferromagnetic metal sheets to enable the telescopic partition plate to contract.

Description

Technical Field

[0001] The present invention relates to the field of shield construction, and in particular to a concrete support device and method for a close-range subway shield tunnel crossing an operating tunnel. Background Art

[0002] With the rapid development of urban transportation systems, the practice of subway shield tunnels crossing existing tunnel lines is increasing. While subway shield construction offers advantages such as high efficiency and environmental friendliness, crossing existing tunnel lines presents challenges such as complex geological conditions, stringent settlement control requirements, and ensuring safe tunnel operations. Settlement control on railway lines is directly related to the smoothness and safety of train operations, and accidents can have serious social and economic impacts. Therefore, in-depth research on construction control technologies for subway shield tunnels crossing existing tunnel lines is crucial for ensuring tunnel safety and promoting the sustainable development of subway construction.

[0003] In the prior art, for example, patent announcement number CN115839244B discloses a support device and method for a close-range subway shield tunnel crossing an operating tunnel. A plurality of elastic sealing plugs are respectively slidably inserted into a plurality of grouting holes in the vertical direction so that soil particles in the grouting holes will not enter the grouting pipe. However, during the grouting process, the grouting holes and the gaps around the grouting holes will be filled by injecting slurry. The provision of elastic sealing plugs will cause the air in the original grouting holes and the gaps around the grouting holes to be unable to flow back, resulting in bubbles in the slurry, affecting the support strength. In addition, the grouting pressure can determine the penetration of the slurry into the gaps around the grouting holes. The stronger the penetration, the better the support effect and the more difficult it is to cause settlement. Therefore, constructing a horizontal pressurized space can effectively enhance the penetration of the slurry. Summary of the Invention

[0004] In order to solve the above problems, the present invention provides a concrete support device and method for a close-range subway shield tunnel passing through an operating tunnel, which is used to promote the penetration of slurry into the gaps around grouting holes.

[0005] In order to achieve the above-mentioned object, the technical solution of the present invention is as follows: a concrete support device for a close-range subway shield tunnel passing through an operating tunnel, comprising a tunnel segment, on which a plurality of grouting support assemblies are provided;

[0006] The grouting support assembly includes a hollow tube body, an injection port connected to the hollow tube body is provided on the inner side of the tunnel segment, and a plurality of telescopic baffles are provided on the hollow tube body. The telescopic baffles are each provided with an elastic member for driving the telescopic baffles to extend. The telescopic baffles are fixedly connected to a ferromagnetic metal sheet. The hollow tube body is provided with a plurality of release ports, each of which is located between the telescopic baffles.

[0007] It also includes a probe rod, which is detachably connected to the injection port through a snap fit. A plurality of electromagnets are arranged in the probe rod, and the electromagnets are used to attract ferromagnetic metal sheets to shrink the telescopic partition.

[0008] The above scheme has the following beneficial effects:

[0009] 1. In this solution, grouting holes are drilled in the sidewalls of the shield tunnel to provide additional grouting to stabilize the surrounding soil. This reduces settlement caused by collapse of the tunnel roof and surrounding soil, ensuring the stability of the soil above. This also effectively minimizes the impact on the operating tunnel and reduces the probability of settlement caused by the subway shield tunnel.

[0010] 2. In this solution, the grouting support assembly will be inserted into the grouting hole. Before it fully enters, the probe rod will engage the injection port, and the electromagnet will attract the ferromagnetic metal sheet, causing the telescopic partition to retract. When the grouting support assembly reaches the desired position, the electromagnet of the probe rod will be de-energized, causing the telescopic partition to pop out. The telescopic partition will press against the sidewall of the grouting hole, forming a chamber between the telescopic partitions. This can reduce the spread of slurry released from the release port between the telescopic partitions to the upper and lower sides, and instead focus on penetrating the gaps in the soil layer around the grouting hole, thereby building a more solid grouting layer, improving the strength of the tunnel roof and surrounding soil layers, and reducing the impact on the operating tunnel.

[0011] Furthermore, the telescopic partition includes a motherboard and a sub-board. The motherboard is a hollow structure. The motherboard and the sub-board are nested. The motherboard is fixedly connected to the outside of the hollow tube body. The elastic part is located inside the motherboard. One end of the elastic part is fixedly connected to the motherboard, and the other end of the elastic part is fixedly connected to the sub-board.

[0012] Beneficial effect: The daughter board is nested in the mother board, and when the magnetic attraction of the electromagnet disappears, the daughter board will pop out from the mother board due to the elastic force of the elastic member.

[0013] Furthermore, the sub-plate is a hollow structure and is connected to the mother plate. A through hole is provided on the side of the sub-plate away from the mother plate, and the through hole is filled with fragile blocks. The fragile blocks are used to break when the fluid pressure between the two telescopic partitions reaches a preset value after grouting.

[0014] Beneficial effects: When the slurry is injected, the air in the chamber formed between the two telescopic baffles will be displaced, forcing it to press into the gaps in the soil layer around the slurry hole, affecting the slurry's penetration. The fragile blocks will break when the fluid pressure in the chamber formed between the telescopic baffles reaches a preset value, connecting the chamber formed between the two telescopic baffles with the telescopic baffles. Since the through-hole is located on the side away from the motherboard, it is closer to the compressed air. Once connected, the through-hole will preferentially draw air into the telescopic baffles, thereby reducing the impact of air on slurry penetration. At the same time, the air is drawn into the telescopic baffles. The telescopic baffles are made of materials such as steel and alloys. Compared with bubbles in the slurry, the cavities in the telescopic baffles have less impact on the overall strength.

[0015] Furthermore, a sealing gasket is provided on an edge of the daughter board away from the mother board.

[0016] Beneficial effect: The sealing gasket can make the edge of the sub-plate fit the irregular contour of the grouting hole side wall.

[0017] Furthermore, a one-way valve is provided at each release port.

[0018] Beneficial effect: The one-way valve can prevent the sediment and impurities in the grouting hole from flowing back into the hollow pipe body, reducing its impact on the grouting process.

[0019] Furthermore, a plurality of convex strips are provided on the motherboard.

[0020] Beneficial effect: The convex strips on the motherboard can form a mosaic after the slurry solidifies, so as to enhance the matching effect between the motherboard and the slurry.

[0021] A concrete support method for a close-range subway shield tunnel passing through an operating tunnel, comprising:

[0022] Step 1: Locate the close-range crossing point of the subway shield in the operating tunnel and perform surface grouting reinforcement on the operating tunnel;

[0023] Step 2: When laying tunnel segments in a subway shield machine, grouting holes are constructed on the side walls of the shield tunnel. The tunnel segment grouting support assembly is placed in the grouting holes. The tunnel segments are fixed to the side walls of the shield tunnel by bolts. The electromagnet of the probe rod is de-energized to eject the telescopic partition, and then the probe rod is removed.

[0024] Step three, pressurized slurry is injected through the injection port on the inner side of the tunnel segment, and the slurry is released from the release port to between each telescopic baffle, so that the slurry penetrates into the gap around the grouting hole in the chamber formed between the two telescopic baffles; after the telescopic baffle pops out, the hollow structure in the mother plate will form a negative pressure state due to the detachment of the sub-plates. When the fluid pressure in the chamber formed between the two telescopic baffles is greater than the preset value, the fragile blocks will break, allowing the air squeezed to the edge of the chamber formed between the two telescopic baffles to enter the telescopic baffle from the through hole.

[0025] Beneficial Effects: Because the slurry has not yet solidified immediately after the shield tunnel exits the tunnel, surface grouting reinforcement is required in the operating tunnel in advance to prevent the ground from settling in a short period of time. The shield tunnel is then reinforced using hollow tubes, minimizing the impact on the operating tunnel.

[0026] Furthermore, in step one, the depth range of the surface grouting reinforcement is greater than the radius of the operating tunnel.

[0027] Beneficial effect: Through grouting reinforcement of the operating tunnel surface at a sufficient depth, the risk of settlement occurring immediately after the shield exits the tunnel can be reduced.

[0028] Furthermore, in step one, the surface grouting reinforcement adopts a method of obliquely arranging grouting pipes, and the angle between the grouting pipes and the horizontal plane is between 45° and 90°.

[0029] Beneficial effects: Oblique grouting pipes can be arranged crosswise at different angles to form a three-dimensional reinforcement network, covering lateral or deep weak areas that are difficult to reach with vertical grouting.

[0030] Furthermore, in step 3, the initial setting time of the slurry is within 8-12 hours, and the shrinkage rate and decantation rate of the slurry are both less than 5%.

[0031] Beneficial Effects: An initial setting time of 8-12 hours ensures the slurry maintains fluidity after injection, fully filling gaps in the shield tail and cracks in the surrounding soil, reducing the risk of cavitation. Low shrinkage means minimal volume change after hardening, ensuring a long-term, tight fit between the segments and the surrounding rock, preventing microcracks caused by shrinkage and minimizing the risk of water leakage.

[0032] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is an axonometric diagram of an embodiment of a concrete support device for a close-range subway shield tunnel passing through an operating tunnel according to the present invention;

[0034] Figure 2 This is a schematic diagram of the telescopic diaphragm structure of an embodiment of the concrete support equipment for a close-range subway shield tunnel passing through an operating tunnel according to the present invention;

[0035] Figure 3 A schematic diagram of a probe rod in an embodiment of a concrete support device for a close-range subway shield tunnel crossing an operating tunnel according to the present invention;

[0036] Figure 4 This is a schematic diagram of the steps of an embodiment of the method for concrete support of a close-range subway shield tunnel passing through an operating tunnel according to the present invention.

[0037] The figure marks in the drawings of the specification include: 1. tunnel segment; 2. grouting support assembly; 3. hollow tube body; 4. telescopic partition; 5. elastic member; 6. ferromagnetic metal sheet; 7. release port; 8. probe rod; 9. electromagnet; 10. motherboard; 11. daughter board; 12. through hole; 13. fragile block; 14. sealing gasket; 15. one-way valve; 16. convex strip. DETAILED DESCRIPTION

[0038] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0039] In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limitations on the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0040] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0041] The following is further described in detail through specific implementation methods:

[0042] Example 1:

[0043] As attached Figures 1-4 As shown: A concrete support device for a close-range subway shield tunnel passing through an operating tunnel, comprising a tunnel segment 1, on which a plurality of grouting support assemblies 2 are provided.

[0044] The grouting support assembly 2 comprises a hollow tube 3, with an injection port connected to the hollow tube 3 provided on the inside of the tunnel segment 1. The grouting support assembly 2 can be bolted to the outside of the tunnel segment 1 and inserted directly into a pre-constructed grouting hole. Alternatively, the injection port can be constructed in the tunnel segment 1, followed by a grouting hole. Finally, the grouting support assembly 2 can be inserted through the injection port and fixedly connected to the tunnel segment 1 using bolts.

[0045] The hollow tube 3 is provided with a plurality of telescopic baffles 4, each comprising a motherboard 10 and a daughterboard 11. The motherboard 10 is a hollow structure, nested within the motherboard 10 and welded to the exterior of the hollow tube 3. An elastic member 5 is provided within the motherboard 10, one end of which is welded to the motherboard 10, and the other end of which is welded to the daughterboard 11. Ferromagnetic metal sheets 6 are welded to the telescopic baffles 4. The hollow tube 3 is provided with a plurality of release ports 7, all located between the telescopic baffles 4.

[0046] The sub-plate 11 is a hollow structure and is connected to the mother plate 10. A through hole 12 is provided on the side of the sub-plate 11 away from the mother plate 10. The through hole 12 is filled with fragile blocks 13. The fragile blocks 13 are used to break when the fluid pressure between the two telescopic partitions 4 reaches a preset value after grouting.

[0047] A sealing gasket 14 is attached to the edge of the daughter board 11 away from the mother board 10. A one-way valve 15 is attached to the release opening 7. A plurality of convex strips 16 are welded and fixed to the mother board 10.

[0048] It also includes a probe rod 8, which is detachably connected to the injection port through a snap-fit. A plurality of electromagnets 9 are provided in the probe rod 8, and the electromagnets 9 are used to attract the ferromagnetic metal sheet 6 to shrink the telescopic partition 4.

[0049] Grouting holes are drilled in the sidewalls of the shield tunnel to provide additional grouting to the surrounding soil, reducing settlement caused by collapse of the tunnel roof and surrounding soil, thereby ensuring the stability of the soil above. This effectively minimizes the impact on the operating tunnel and reduces the probability of settlement caused by the subway shield tunnel.

[0050] The grouting support assembly 2 will be inserted into the grouting hole. Before it is fully inserted, the probe rod 8 will be engaged in the injection port, and the ferromagnetic metal sheet 6 will be attracted by the electromagnet 9, causing the telescopic partition 4 to shrink. When the grouting support assembly 2 reaches the appropriate position, the electromagnet 9 of the probe rod 8 will be de-energized, causing the telescopic partition 4 to pop out. The telescopic partition 4 will press against the side wall of the grouting hole, thereby forming a chamber between the telescopic partitions 4. The sealing gasket 14 can make the edge of the sub-plate 11 fit the irregular contour of the side wall of the grouting hole. The telescopic partition 4 will contact the side wall of the grouting hole with a greater pressure through the elastic force of the elastic member 5, which can reduce the slurry released from the release port 7 between the telescopic partitions 4 from spreading to the upper and lower sides, thereby concentrating on penetrating into the gaps in the soil layer around the grouting hole, so as to build a more solid grouting layer, improve the strength of the tunnel top and surrounding soil layers, and reduce the impact on the operating tunnel.

[0051] The ridges 16 on the motherboard 10 can be interlocked after the slurry solidifies, thereby enhancing the matching effect between the motherboard 10 and the slurry.

[0052] The one-way valve 15 can prevent the mud and sand impurities in the grouting hole from flowing back into the hollow tube body 3, reducing its impact on the grouting process. When the slurry is injected, the air in the chamber formed between the two telescopic baffles 4 will be squeezed out, causing it to press into the gaps in the soil layer around the slurry hole, which will affect the penetration effect of the slurry. The fragile block 13 can break after the fluid pressure in the chamber formed between the telescopic baffles 4 reaches a preset value, connecting the chamber formed between the two telescopic baffles 4 with the telescopic baffle 4. Since the through hole 12 is located on the side away from the motherboard 10, it is closer to the compressed air. After the through hole 12 is connected, the air will be first sucked into the telescopic baffle 4, thereby reducing the impact of air on slurry penetration. At the same time, the air will be sucked into the telescopic baffle 4. The telescopic baffle 4 is made of steel, alloy and other materials. Compared with the bubbles in the slurry, the cavity in the telescopic baffle 4 has less impact on the overall strength.

[0053] A concrete support method for a close-range subway shield tunnel passing through an operating tunnel, comprising:

[0054] Step 1: Locate the close-range crossing point of the subway shield in the operating tunnel and perform surface grouting reinforcement on the operating tunnel. The depth range of the surface grouting reinforcement is greater than the radius of the operating tunnel. The surface grouting reinforcement adopts the method of obliquely arranging grouting pipes, and the angle between the grouting pipes and the horizontal plane is between 45° and 90°.

[0055] Step 2: When laying the tunnel segment 1 in the subway shield, a grouting hole is constructed on the side wall of the shield tunnel, and the grouting support assembly 2 of the tunnel segment 1 is placed in the grouting hole. The tunnel segment 1 is fixed to the side wall of the shield tunnel by bolts, and the electromagnet 9 of the probe rod 8 is de-energized to make the telescopic partition 4 pop out, and then the probe rod 8 is removed;

[0056] Step three: slurry is pressurized and injected through the injection port on the inner side of the tunnel segment 1. The initial setting time of the slurry is within 8-12 hours, and the shrinkage and decantation rates are both less than 5%. The slurry is released from the release port 7 between each telescopic baffle 4, allowing the slurry to penetrate the gaps around the grouting holes within the cavity formed between the two telescopic baffles 4. After the telescopic baffle 4 is ejected, the hollow structure within the motherboard 10 creates a negative pressure state due to the separation of the sub-plates 11. When the fluid pressure in the cavity formed between the two telescopic baffles 4 exceeds a preset value, the fragile blocks 13 shatter, allowing the air squeezed to the edge of the cavity between the two telescopic baffles 4 to enter the telescopic baffle 4 through the through-holes 12.

[0057] Because the grouting material hasn't solidified immediately after the shield tunnel exits, surface grouting is necessary to reinforce the operating tunnel in advance to prevent rapid ground settlement. Surface grouting reinforcement in operating tunnels at sufficient depth can reduce the risk of settlement immediately after the shield tunnel exits. Oblique grouting pipes can be arranged at different angles to form a three-dimensional reinforcement network, covering lateral or deep weak areas difficult to reach with vertical grouting.

[0058] The hollow tube 3 is then used to reinforce the shield tunnel with grouting, minimizing the impact on the operating tunnel. An initial setting time of 8-12 hours ensures the grout maintains fluidity after injection, fully filling the gaps at the shield tail and cracks in the surrounding soil, reducing the risk of cavitation. The low shrinkage rate means minimal volume change after hardening, ensuring a tight, long-term fit between the segments and the surrounding rock, preventing microcracks caused by shrinkage and minimizing the risk of water leakage.

[0059] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will readily appreciate that other variations or modifications based on the above descriptions are possible. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. A concrete support device for a close-range subway shield tunnel passing through an operating tunnel, characterized in that: It comprises a tunnel segment (1), wherein a plurality of grouting support assemblies (2) are provided on the tunnel segment (1); The grouting support assembly (2) comprises a hollow tube body (3); an injection port communicating with the hollow tube body (3) is provided on the inner side of the tunnel segment (1); a plurality of telescopic baffles (4) are provided on the hollow tube body (3); each of the telescopic baffles (4) is provided with an elastic member (5) for driving the telescopic baffles (4) to extend; a ferromagnetic metal sheet (6) is fixedly connected to the telescopic baffles (4); and a plurality of release ports (7) are provided on the hollow tube body (3); the release ports (7) are all located between the telescopic baffles (4); The invention also includes a probe rod (8) which is detachably connected to the injection port by snapping. A plurality of electromagnets (9) are provided in the probe rod (8) and are used to attract the ferromagnetic metal sheet (6) to shrink the telescopic partition (4).

2. The concrete support equipment for close-range subway shield tunneling through an operating tunnel according to claim 1 is characterized in that: The telescopic partition (4) includes a motherboard (10) and a sub-board (11). The motherboard (10) is a hollow structure. The motherboard (10) and the sub-board (11) are nested. The motherboard (10) is fixedly connected to the outside of the hollow tube (3). The elastic member (5) is located inside the motherboard (10). One end of the elastic member (5) is fixedly connected to the motherboard (10), and the other end of the elastic member (5) is fixedly connected to the sub-board (11).

3. The concrete support equipment for close-range subway shield tunneling through an operating tunnel according to claim 2 is characterized in that: A through hole (12) is provided on a side of the sub-plate (11) away from the mother plate (10), and the through hole (12) is filled with fragile blocks (13). The fragile blocks (13) are used to break when the fluid pressure between the two telescopic partitions (4) reaches a preset value after grouting.

4. The concrete support equipment for close-range subway shield tunneling through an operating tunnel according to claim 3 is characterized in that: A sealing gasket (14) is provided on the edge of one side of the daughter board (11) away from the mother board (10).

5. The concrete support equipment for close-range subway shield tunneling through an operating tunnel according to claim 4 is characterized in that: A one-way valve (15) is provided at each release port (7).

6. The concrete support equipment for close-range subway shield tunneling through an operating tunnel according to claim 5 is characterized in that: A plurality of convex strips (16) are provided on the motherboard (10).

7. A method for concrete support of a close-range subway shield tunnel passing through an operating tunnel, based on the method for concrete support equipment of a close-range subway shield tunnel passing through an operating tunnel according to claim 6, characterized in that: include: Step 1: Locate the close-range crossing point of the subway shield in the operating tunnel and perform surface grouting reinforcement on the operating tunnel; Step 2: When laying the tunnel segment (1) in the subway shield, a grouting hole is constructed on the side wall of the shield tunnel, and the tunnel segment (1) grouting support assembly (2) is placed in the grouting hole, the tunnel segment (1) is fixed to the side wall of the shield tunnel by bolts, the electromagnet (9) of the probe rod (8) is powered off, the telescopic partition (4) is ejected, and the probe rod (8) is taken out; Step three, pressurized slurry is injected through the injection port on the inner side of the tunnel segment (1), and the slurry is released from the release port (7) to between each telescopic baffle (4), so that the slurry penetrates into the gap around the grouting hole in the chamber formed between the two telescopic baffles (4); after the telescopic baffle (4) pops out, the hollow structure in the mother plate (10) will form a negative pressure state due to the separation of the sub-plate (11), and when the fluid pressure in the chamber formed between the two telescopic baffles (4) is greater than a preset value, the fragile block (13) breaks, so that the air squeezed to the edge of the chamber formed between the two telescopic baffles (4) enters the telescopic baffle (4) from the through hole (12).

8. The method for concrete support of a close-range subway shield tunnel passing through an operating tunnel according to claim 7 is characterized in that: In step 1, the depth range of the surface grouting reinforcement is greater than the radius of the operating tunnel.

9. The method for concrete support of a close-range subway shield tunnel passing through an operating tunnel according to claim 8, characterized in that: In step one, the surface grouting reinforcement adopts the method of obliquely arranging the grouting pipes, and the angle between the grouting pipes and the horizontal plane is between 45° and 90°.

10. The method for concrete support of a close-range subway shield tunnel passing through an operating tunnel according to claim 9, characterized in that: The initial setting time of the slurry in step 3 is within 8-12 hours, and the shrinkage rate and decantation rate of the slurry are both less than 5%.

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