A TBM shield and method of use thereof

Abstract

The application discloses a TBM shield, which comprises a cutter head (1), a main drive (2) arranged at the rear end of the cutter head (1), a top shield (3) arranged on the main drive (2), a top shield flange plate (4) arranged horizontally on the top shield (3), and a chain plate mechanism arranged on the top shield flange plate (4) and surrounding the top shield flange plate (4). The application has the advantages of ingenious structure design, reliable use and low cost. When the TBM shield encounters adverse geological conditions such as large deformation and rock burst, the application can reduce the friction between the surrounding rock and the shield, enable the TBM to move forward and backward, reduce the occurrence of TBM jamming accidents, expand the rock stratum through the cutting teeth, and ensure the smooth passing of the TBM through the deformation section.

Description

Technical Field

[0001] This invention relates to TBM construction, and in particular to a TBM shield and its usage method. Background Technology

[0002] Currently, for tunnels constructed using open-face TBMs, the shields are designed to be retractable. In cases of tunnel deformation, the retracted shield can pass through the deformed section, providing a certain degree of anti-jamming capability. However, in fractured zones or under conditions of large deformation, the surrounding rock converges and deforms too rapidly. When the convergence exceeds the shield's retractability, the pressure from the surrounding rock layers presses entirely onto the shield. When the friction between the shield and the surrounding rock exceeds the TBM's thrust, the TBM shield becomes stuck in the deformed rock layer, necessitating a shutdown for repair. Due to the stress caused by the weight of the rock layer above the tunnel, the deformation rate of the tunnel arch is more pronounced than that of the sides. Initially, jamming primarily occurs at the arch; as time progresses, excessive deformation on the sides can jam the shield. The longer the jamming persists, the more difficult it becomes to resolve. After jamming occurs, the space occupied by the TBM prevents the use of large machinery to clear the rock above the shield, requiring manual labor, which is both time-consuming and inefficient.

[0003] Currently, the main method to prevent TBM jamming is to use cutterhead widening, which increases the tunnel excavation diameter by a certain amount by installing widening cutters, artificially increasing the allowable deformation range of the surrounding rock and buying time for the subsequent shield to pass. However, this method has a limited widening depth (generally around 5cm); and because tunnel widening is a full-face widening, the position of the TBM bottom shield, which sits on the tunnel's bottom arch, is also lowered by the same amount compared to the design position. As the TBM continues to advance, the TBM excavation cross-section will become increasingly lower, requiring continuous TBM attitude adjustments to prevent head-down, thus multiplying the difficulty of TBM tunneling alignment control. Summary of the Invention

[0004] The purpose of this invention is to provide a TBM shield and its usage method that can reduce the friction between the surrounding rock and the shield when encountering adverse geological conditions such as large deformation and rock bursts, enabling the TBM to move back and forth and reducing the occurrence of TBM jamming accidents.

[0005] The objective of this invention is achieved through the following technical solution: a TBM shield, comprising a cutterhead, a main drive located at the rear end of the cutterhead, a top shield located on the main drive, a top shield flange horizontally arranged on the top shield, and a chain plate mechanism arranged on and around the top shield flange.

[0006] The chain plate mechanism includes a front gear and a rear gear located at both ends of the top shield flange. The front gear and the rear gear are hinged to both ends of the top shield flange via pins A and B, respectively. A chain plate assembly consisting of multiple chain plate units is fitted onto the front gear and the rear gear. A hydraulic motor for driving the rear gear to rotate is provided on the side of the rear gear.

[0007] Further description: the chain plate unit includes a chain plate and chain plate links. The chain plate is disposed on the upper surface of the chain plate link. A chain link B is disposed at the center of the lower end face of the chain plate. Chain links A are disposed symmetrically on both sides of the chain link B. Pin holes are disposed on the front and rear sides of the chain plate link. Adjacent chain plate links are connected by pins C passing through the pin holes.

[0008] In this invention, the top shield flange includes a frame welded from steel plates, and a support is horizontally arranged within the frame to divide the inner cavity of the frame into an upper compartment and a lower compartment; a partition is provided at intervals on the upper end face of the support, the partition dividing the upper compartment into multiple smaller compartments, and a support roller is provided in each smaller compartment; a groove is provided on the surface of the support roller, and the groove respectively cooperates with link A and link B.

[0009] To facilitate excavation of the rock surface, cutting teeth are provided on the upper end face of the chain plate at both ends.

[0010] In order to keep the chain plate tensioned, a tensioning mechanism is provided between the rear gear and the top shield flange.

[0011] The tensioning mechanism includes a telescopic bracket, one end of which is connected to the frame and the other end of which is connected to pin B.

[0012] In this invention, it is used in two ways:

[0013] A method for using a TBM shield, the method comprising the following steps:

[0014] S1: Based on the design data and advanced geological forecast results, comprehensively assess the risk of jamming ahead, and shut down the machine when the risk of jamming is high, and activate the shield structure.

[0015] S2: Assembly chain plate mechanism;

[0016] S3: Use traction ropes to install the assembled chain plate structure onto the shield, and use the tensioning mechanism to smoothly unfold the chain plate structure;

[0017] S4: Lift the shield to tighten the chain plate structure against the tunnel rock surface;

[0018] S5: The TBM advances forward, while the chain plate structure moves backward in sync;

[0019] S6: Immediately apply support after the surrounding rock exposes the shield;

[0020] S7: The TBM passes through the jamming risk section, removes the chain plate structure, and resumes normal tunneling.

[0021] A method for using a TBM shield, the method comprising the following steps:

[0022] S1: Based on the design data and advanced geological forecast results, comprehensively assess the risk of machine jamming due to deformation of the surrounding rock ahead, and activate the shield structure when the risk of machine jamming is high.

[0023] S2: Assemble the chain plate mechanism with cutting teeth;

[0024] S3: Use a traction rope to install the assembled chain tooth structure onto the shield, and use a tensioning device to smoothly unfold the chain tooth structure.

[0025] S4: Lift the shield to bring the chain tooth structure closer to the converging rock surface;

[0026] S5: Start the hydraulic motor to drive the chain plate with chain teeth to rotate, expand the rock strata, and expand the tunnel cross section to the required position;

[0027] S6: The TBM continues to advance forward, and support is immediately provided after the surrounding rock exposes the shield;

[0028] S6: Repeat S4-S6 until the TBM passes the jamming risk section, remove the chain tooth structure, and restore normal tunneling.

[0029] Due to the adoption of the above technical solution, the present invention has the advantages of ingenious structural design, reliable use and low cost. It can reduce the friction between the surrounding rock and the shield when encountering adverse geological conditions such as large deformation and rock bursts, enabling the TBM to move back and forth and reducing the occurrence of TBM jamming accidents. At the same time, it can also expand the rock strata through the cutting teeth to ensure that the TBM can pass through the deformation section smoothly. Attached Figure Description

[0030] The accompanying drawings of this invention are described below:

[0031] Figure 1 This is a schematic diagram of the structure of the present invention;

[0032] Figure 2 This is a schematic diagram of the cross-sectional layout of the shield structure of the present invention;

[0033] Figure 3 This is a schematic diagram of the chain plate mechanism arrangement of the present invention;

[0034] Figure 4 This is a schematic diagram of the chain plate unit structure of the present invention;

[0035] Figure 5This is a planar schematic diagram of the chain plate mechanism of the present invention;

[0036] Figure 6 This is a schematic diagram of the chain plate end structure of the present invention;

[0037] Figure 7 This is a schematic diagram of the middle structure of the chain plate of the present invention. Detailed Implementation

[0038] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings. However, the present invention is not limited to these embodiments. Any improvements or substitutions based on the basic spirit of these embodiments shall still fall within the scope of protection claimed by the claims of the present invention.

[0039] Example 1: As Figure 1 , 2 As shown in 3, 4, 5, 6, and 7, a TBM shield includes a cutter head 1, a main drive 2 is provided at the rear end of the cutter head 1, a top shield 3 is provided on the main drive 2, a top shield flange plate 4 is horizontally provided on the top shield 3, and a chain plate mechanism is provided on and around the top shield flange plate 4.

[0040] The chain plate mechanism includes a front gear 5 and a rear gear 6 disposed at both ends of the top shield flange plate 4. The front gear 5 and the rear gear 6 are respectively hinged to both ends of the top shield flange plate 4 via pins A7 and B8. A chain plate group composed of multiple chain plate units is sleeved on the front gear 5 and the rear gear 6. A hydraulic motor 9 for driving the rear gear 6 to rotate is disposed on the side of the rear gear 6.

[0041] Furthermore, the chain plate unit includes a chain plate 10 and chain plate links 11. The chain plate 10 is disposed on the upper surface of the chain plate link 11. A chain link B12 is disposed at the center of the lower end face of the chain plate 10. Chain links A13 are disposed symmetrically on both sides of the chain link B12. Pin holes 14 are provided on both the front and rear sides of the chain plate link 11. Adjacent chain plate links 11 are connected by pins C15 passing through the pin holes 14.

[0042] In this invention, the shield itself has a telescopic function. During tunneling, the shield extends to support the deformed rock surface with the chain plate unit, which plays a temporary support role. With the sliding of the chain plate, the deformation of the surrounding rock can be further reduced to ensure safety while preventing the shield from getting stuck.

[0043] The hydraulic motor 9 operates, driving the front gear to rotate, which in turn drives the entire chain plate mechanism to rotate. As the chain plate mechanism rotates, the cutting teeth 23 simultaneously excavate the converging and deformed rock surface, and transport the cut rock debris to the tail of the shield to prevent excessive deformation of the surrounding rock from jamming the shield, thus ensuring safety.

[0044] The chain plate mechanism is adopted, and the chain plate 10 is thicker. It mainly bears the external load and can be used in working conditions where there is a risk of machine jamming, such as large deformation in tunnels and rock burst deformation in hard rock.

[0045] In this invention, the top shield flange 4 includes a frame welded from steel plates. A support 18 is horizontally arranged within the frame, dividing the inner cavity of the frame into an upper compartment 16 and a lower compartment 17. A partition 19 is provided on the upper end face of the support 18, which divides the upper compartment into multiple smaller compartments 20. A support roller 21 is provided in each smaller compartment 20. A groove 22 is provided on the surface of the support roller 21, and the groove 22 respectively cooperates with link A13 and link B12.

[0046] The chain plate unit of the present invention is detachable. In areas with good surrounding rock, the chain plate structure and the front gear can be removed, and the lower compartment 17 of the shield can be used as a storage compartment for steel bars.

[0047] The shield of the present invention has a telescopic function. During the tunneling process, the shield extends to support the deformed rock surface and play a temporary support role. With the sliding of the chain plate 10, the deformation of the surrounding rock can be further reduced to ensure safety while preventing the shield from getting stuck.

[0048] Example 2: To facilitate the excavation of the rock surface, cutting teeth 23 are provided on the upper end face of the chain plate 10 at both ends. When the rock strata above the shield deform and converge, the top shield is pushed out, and the chain plate unit on the top shield is activated to rotate backward. The cutting teeth 23 fixed on the chain plate 10 are used to break up the converging and sinking surrounding rock and transport it to the tail of the shield, thus completing the excavation of the rock strata and preventing the shield from getting stuck.

[0049] Among them, when using the cutting tooth 23 for excavation, it is mainly used in soft rock, fractured zones, and large deformation zones.

[0050] In this invention, the circumferential arrangement spacing of the chain plate mechanism can be calculated and determined according to the surrounding rock conditions of the tunnel, ensuring that the outer cutting teeth 23 arranged on the adjacent chain plates 10 can break the intermediate rock layer.

[0051] If the cutting tooth 10 is damaged, it can be replaced by rotating it to the tail of the shield.

[0052] In this invention, a tensioning mechanism is provided between the rear gear 6 and the top shield flange 4 in order to tension the chain plate.

[0053] The tensioning mechanism includes a telescopic bracket 25, one end of which is connected to the frame and the other end is connected to the pin B8.

[0054] The chain plate 10 is designed to be detachable. Depending on the construction conditions, a chain plate mechanism or a chain plate mechanism with cutting teeth can be used. The chain plate mechanism cannot be used for enlarged excavation, while the chain plate mechanism with cutting teeth can be used for enlarged excavation.

[0055] Both chain plate mechanisms and chain plate mechanisms with cutting teeth can be used to prevent jamming. Anti-jamming can be divided into active and passive anti-jamming.

[0056] Active anti-jamming: Based on the on-site working conditions, the chain plate 10 is replaced with a chain plate structure with cutting teeth 23 to expand the excavation of the deformed and convergent rock surface and prevent the machine from jamming.

[0057] Passive anti-jamming: Based on the site conditions, a chain plate 10 structure is adopted. The chain plate structure bears the rock load of convergent deformation and prevents jamming by rolling the chain plate structure.

[0058] In this invention, it is used in two ways:

[0059] A method for using a TBM shield, the method comprising the following steps:

[0060] S1: Based on the design data and advanced geological forecast results, comprehensively assess the risk of jamming ahead, and shut down the machine when the risk of jamming is high, and activate the shield structure.

[0061] S2: Assemble the chain plate structure;

[0062] S3: Use traction ropes to install the assembled chain plate structure onto the shield, and use the tensioning mechanism to smoothly unfold the chain plate structure;

[0063] S4: Lift the shield to tighten the chain plate structure against the tunnel rock surface;

[0064] S5: The TBM advances forward, while the chain plate structure moves backward in sync;

[0065] S6: Immediately apply support after the surrounding rock exposes the shield;

[0066] S7: The TBM passes through the jamming risk section, removes the chain plate structure, and resumes normal tunneling.

[0067] A method for using a TBM shield, the method comprising the following steps:

[0068] S1: Based on the design data and advanced geological forecast results, comprehensively assess the risk of machine jamming due to deformation of the surrounding rock ahead, and activate the shield structure when the risk of machine jamming is high.

[0069] S2: Assemble the chain plate mechanism with cutting teeth;

[0070] S3: Use a traction rope to install the assembled chain tooth structure onto the shield, and use a tensioning device to smoothly unfold the chain tooth structure.

[0071] S4: Lift the shield to bring the chain tooth structure closer to the converging rock surface;

[0072] S5: Start the hydraulic motor to drive the chain plate with chain teeth to rotate, expand the rock strata, and expand the tunnel cross section to the required position;

[0073] S6: The TBM continues to advance forward, and support is immediately provided after the surrounding rock exposes the shield;

[0074] S6: Repeat S4-S6 until the TBM passes the jamming risk section, remove the chain tooth structure, and restore normal tunneling.

Claims

1. A TBM shield, comprising a cutterhead (1), a main drive (2) disposed at the rear end of the cutterhead (1), and a top shield (3) disposed on the main drive (2), characterized in that: A top shield flange plate (4) is horizontally arranged on the top shield (3), and a chain plate mechanism is arranged on and around the top shield flange plate (4). The chain plate mechanism includes a front gear (5) and a rear gear (6) disposed at both ends of the top shield flange plate (4). The front gear (5) and the rear gear (6) are respectively hinged to both ends of the top shield flange plate (4) via pin A (7) and pin B (8). A chain plate group consisting of multiple chain plate units is sleeved on the front gear (5) and the rear gear (6). A hydraulic motor (9) for driving the rear gear (6) to rotate is disposed on the side of the rear gear (6). The chain plate unit includes a chain plate (10) and chain plate links (11). The chain plate (10) is disposed on the upper surface of the chain plate link (11). A chain link B (12) is disposed at the center of the lower end face of the chain plate (10). Chain links A (13) are disposed symmetrically on both sides of the chain link B (12). Pin holes (14) are provided on the front and rear sides of the chain plate link (11). Adjacent chain plate links (11) are connected by pins C (15) passing through the pin holes (14). The top shield flange (4) includes a frame welded from steel plates. A support (18) is horizontally arranged in the frame to divide the inner cavity of the frame into an upper compartment (16) and a lower compartment (17). A partition (19) is provided on the upper end face of the support (18), which divides the upper compartment into multiple small compartments (20). A support roller (21) is provided in the small compartment (20). A groove (22) is provided on the surface of the support roller (21), which cooperates with link A (13) and link B (12) respectively.

2. The TBM shield as described in claim 1, characterized in that: Cutting teeth (23) are provided on the upper end face of the chain plate (10) and at both ends thereon.

3. The TBM shield as described in claim 2, characterized in that: A tensioning mechanism is provided between the rear gear (6) and the top shield flange (4).

4. The TBM shield as described in claim 3, characterized in that: The tensioning mechanism includes a telescopic bracket (25), one end of which is connected to the frame and the other end is connected to the pin B (8).

5. A method of using a TBM shield as described in any one of claims 2-4, characterized in that, The method includes the following steps: S1: Based on the design data and advanced geological forecast results, comprehensively assess the risk of jamming ahead, and shut down the machine when the risk of jamming is high, and activate the shield structure. S2: Assemble the chain plate mechanism; S3: Use traction ropes to install the assembled chain plate structure onto the shield, and use the tensioning mechanism to smoothly unfold the chain plate structure; S4: Lift the shield to tighten the chain plate structure against the tunnel rock surface; S5: The TBM advances forward, while the chain plate structure moves backward in sync; S6: Immediately apply support after the surrounding rock exposes the shield; S7: The TBM passes through the jamming risk section, removes the chain plate structure, and resumes normal tunneling.

6. A method of using a TBM shield as described in any one of claims 2-4, characterized in that, The method includes the following steps: S1: Based on the design data and advanced geological forecast results, comprehensively assess the risk of machine jamming due to deformation of the surrounding rock ahead, and activate the shield structure when the risk of machine jamming is high. S2: Assemble the chain plate mechanism with cutting teeth; S3: Use the traction rope to install the assembled chain tooth structure onto the shield, and use the tensioning device to smoothly unfold the chain tooth structure; S4: Lift the shield to bring the chain tooth structure closer to the converging rock surface; S5: Start the hydraulic motor to drive the chain plate with chain teeth to rotate, expand the rock strata, and expand the tunnel cross section to the required position; S6: The TBM continues to advance forward, and support is immediately provided after the surrounding rock exposes the shield; S6: Repeat S4-S6 until the TBM passes the jamming risk section, remove the chain tooth structure, and restore normal tunneling.

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