Method for constructing enclosure structure by adopting hole pile method under limited ground condition
By using the tunnel pile method, combined with reinforcement measures such as capping beams and pipe jacking, the construction problem of retaining piles under ground-constrained conditions in subway station construction was solved, improving construction safety and efficiency and ensuring soil stability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-17
- Publication Date
- 2026-04-03
AI Technical Summary
In subway station construction, ground retaining piles are difficult to construct under limited ground conditions, especially when the running track is present, making normal construction impossible.
The tunnel pile method was adopted, first constructing ground retaining piles, then constructing internal retaining piles in the tunnel section, and reinforcing them with measures such as capping beams, pipe curtains, advanced pipe sheds and temporary concrete frames to form a closed retaining pile structure, thus solving the problem of ground retaining pile construction.
This ensured construction safety and efficiency, reduced the risk of collapse and settlement, and guaranteed the stability of the soil around the subway station.
Smart Images
Figure CN121781600A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of subway station construction technology, and in particular to a method for constructing retaining structures using the tunnel pile method under ground-constrained conditions. Background Technology
[0002] When constructing a subway station, it is necessary to excavate a foundation pit underground.
[0003] If there are no other interfering structures or special circumstances, subway station foundation pits are generally excavated directly using the open-cut method. However, if there are interfering structures or other issues, adjustments may be necessary, such as using a cut-and-cover method.
[0004] In the existing technology, there is a section of running track above the station that needs to be excavated, and during the excavation process, ground retaining piles are usually required to be installed around the foundation pit before the station is excavated. However, the presence of the running track makes it impossible to construct two sections of ground retaining piles normally. Summary of the Invention
[0005] The purpose of this application is to provide a method for constructing retaining structures using the hole-and-pile method under ground-constrained conditions, so as to improve the problem of difficult construction of ground retaining piles under ground-constrained conditions.
[0006] This application provides a method for constructing retaining structures using the tunnel-pile method under confined ground conditions, employing the following technical solution: A method for constructing retaining structures using the tunnel-pile method under confined ground conditions includes the following steps: Ground pile construction: Ground retaining piles are constructed on the ground. The ground retaining piles are set along the first open-cut section and the second open-cut section. Ground retaining piles are also set between the first open-cut section, the second open-cut section and the tunnel section. Shallow foundation pit excavation: construction of the first open excavation section and the second open excavation section; Pipe jacking construction: Construct pipe jacking support beams under the running track, followed by pipe jacking construction; Construction of the cut-and-cover section: Excavation begins from the first and second open-cut sections and proceeds toward the operation to excavate the cut-and-cover section; Construction of piles inside the tunnel: Construct retaining piles inside the tunnel along the edge of the tunnel section, construct piles inside the tunnel at multiple locations on the ground of the tunnel section, and install steel pipe column piles on the piles inside the tunnel. Cover plate construction: Construct the pile top capping beam on the steel pipe column pile, and install the cover plate on the pile top capping beam.
[0007] By adopting the above technical solution, the ground retaining piles are constructed first, and then the tunnel retaining piles are constructed during the construction of the underground excavation section. The tunnel retaining piles are connected with the ground retaining piles to form a closed retaining pile structure, which ensures the safety of subsequent construction, the stability of the soil around the subway station, and construction efficiency.
[0008] Optionally, during the excavation of the first and second open-cut sections, the construction cap beam reinforces the sidewalls of the first and second open-cut sections.
[0009] The above technical solution uses a capping beam to reinforce the sidewalls of the first and second open-cut sections, reducing the possibility of collapse in the first and second open-cut sections and improving construction safety.
[0010] Optionally, during pipe jacking construction, the pile foundation is first laid to create a hole, then the pipe jacking is excavated in the hole, the reinforcing cage is pushed into the pipe jacking, and finally concrete is poured and grouting is performed.
[0011] The above technical solution uses pipe jacking to reinforce the soil, thereby reducing the possibility of track settlement.
[0012] Optionally, before excavating the tunnel section, advance pipe sheds are constructed on both sides of the tunnel section, then the ground retaining piles are broken, and then the tunnel is excavated using the step method. During the excavation of the tunnel section, a temporary concrete frame is constructed inside the tunnel section.
[0013] The above technical solution protects the tunnel section using advanced pipe roofs and temporary concrete frames, ensuring safety during the construction process.
[0014] Optionally, during the construction of the piles inside the tunnel, a low-headroom rotary drilling rig is used to form the hole inside the tunnel. Then, a transfer trolley is used to transfer the steel cage and lower it into the hole inside the tunnel. The steel cage is placed in multiple sections, and adjacent sections are welded together.
[0015] With the above technical solution, since the total length of the steel cage is greater than the height of the tunnel section, the steel cage is divided into multiple sections and placed into the hole in sequence. The multiple sections of the steel cage are then reassembled by welding, which solves the problem of difficult pile construction in the tunnel due to limited space in the tunnel section.
[0016] Optionally, the transfer trolley includes a frame and a clamping assembly, a steering assembly, and a lowering assembly mounted on the frame. The clamping assembly is used to clamp the reinforcing cage, the steering assembly is used to transfer the reinforcing cage to the top of the hole, and the lowering assembly is used to lower the reinforcing cage into the hole.
[0017] By adopting the above technical solution, when lowering the reinforcing cage, the clamping component clamps the reinforcing cage, the turning component transfers the reinforcing cage to the top of the hole, and the lowering component lowers the reinforcing cage into the hole. At this time, the reinforcing cage can be fixed to the opening of the hole with reinforcing bars. This reinforcing cage is the old reinforcing cage. Then, the transfer trolley transfers the new reinforcing cage to the top of the old reinforcing cage and welds the new reinforcing cage to the old reinforcing cage. Then, the fixation of the old reinforcing cage is released, and then the lowering component continues to lower the reinforcing cage. The above steps are repeated until the reinforcing cage reaches the set length and falls into the set position.
[0018] Optionally, the clamping assembly includes a lifting component, an adjusting jack, and a hydraulic cylinder gripper. The lifting component is mounted on the vehicle frame, and the movable end of the lifting component is connected to the adjusting jack. The adjusting jack is horizontally positioned, and the movable end of the adjusting jack is connected to the hydraulic cylinder gripper.
[0019] By adopting the above technical solution, the hydraulic cylinder gripper can easily clamp the steel cage. Then, the height of the steel cage can be adjusted by the lifting component, and the position of the steel cage on the horizontal plane can be adjusted by the steering component and the adjusting jack, which makes it easier for the steel cage to align with the position of the hole inside the hole and improves construction efficiency.
[0020] Optionally, the steering assembly includes a rotating component and a turntable. The rotating component is mounted on the bottom of the vehicle frame, the turntable is rotatably connected to the vehicle frame, and the movable end of the rotating component is connected to the turntable.
[0021] The above technical solution makes it easy to drive the turntable to rotate, which in turn makes it easier to move the steel cage to the top of the hole inside the tunnel.
[0022] Optionally, the lowering assembly includes a winch, a pulley, and a rope. The winch is mounted on the frame, the pulley is mounted on the movable end of the lifting component, one end of the rope is connected to the drum of the winch, and the other end passes around the pulley and is connected to the reinforcing cage.
[0023] By adopting the above technical solution, the winch, rope and pulley work together to facilitate the lowering of the steel cage into the hole.
[0024] Optionally, the turntable is provided with a support plate, a traction rope is connected to the support plate, and a buckle is connected to the traction rope for connecting to the reinforcing cage.
[0025] By adopting the above technical solution, the rebar cage is placed horizontally on the vehicle frame for transportation. When it is necessary to stand the rebar cage upright, the traction rope and buckle are connected to one end of the rebar cage, and then the pull rope is connected to the other end of the rebar cage. The pull rope is pulled by the winch, which in turn pulls the rebar cage to rotate around the buckle. At this time, the operator can hold the rebar cage to assist in the completion. The buckle and traction rope can provide a fulcrum for the rebar cage, reducing the possibility of the rebar cage tipping over during the erection process. After the rebar cage is erected, the hydraulic cylinder jaws clamp the rebar cage.
[0026] In summary, this application includes at least one of the following beneficial technical effects: 1. First, construct the surface retaining piles, and then construct the tunnel retaining piles during the construction of the underground excavation section, connecting the tunnel retaining piles with the surface retaining piles to form a closed retaining pile structure. This ensures the safety of subsequent construction, the stability of the soil around the subway station, and construction efficiency. 2. The sidewalls of the first and second open-cut sections are reinforced by the capping beam to reduce the possibility of collapse in the first and second open-cut sections and improve the safety of construction; 3. By reinforcing the soil with pipe jacks, the possibility of track settlement can be reduced; 4. Protect the tunnel section with advanced pipe roofs and temporary concrete frames to ensure safety during the construction process; 5. Since the total length of the steel cage is greater than the height of the tunnel section, the steel cage is divided into multiple sections and placed into the hole in sequence. The multiple sections of the steel cage are then spliced together by welding to solve the problem of difficult pile construction in the tunnel due to limited space in the tunnel section. 6. When lowering the rebar cage, the clamping component clamps the rebar cage, the turning component moves the rebar cage to the top of the hole, and the lowering component lowers the rebar cage into the hole. At this time, the rebar cage can be fixed to the hole opening with rebar. This rebar cage is the old rebar cage. Then, the transfer trolley moves the new rebar cage to the top of the old rebar cage and welds the new rebar cage to the old rebar cage. Then, the fixation of the old rebar cage is released. Then, the lowering component continues to lower the rebar cage. The above steps are repeated until the rebar cage reaches the set length and falls into the set position. 7. The hydraulic cylinder gripper can easily clamp the steel cage. Then, the height of the steel cage can be adjusted by the lifting component, and the position of the steel cage on the horizontal plane can be adjusted by the steering component and the adjusting jack, which makes it easier for the steel cage to be aligned with the position of the hole inside the hole, thus improving construction efficiency. 8. When the rebar cage is transported on the vehicle frame, it is placed horizontally. When it is necessary to stand the rebar cage upright, the traction rope and the buckle are connected to one end of the rebar cage, and then the pull rope is connected to the other end of the rebar cage. The pull rope is pulled by the winch, which in turn pulls the rebar cage to rotate around the buckle. At this time, the operator can hold the rebar cage to assist in the completion. The buckle and the traction rope can provide a fulcrum for the rebar cage, reducing the possibility of the rebar cage tipping over during the erection process. After the rebar cage is erected, the hydraulic cylinder jaws clamp the rebar cage. Attached Figure Description
[0027] Figure 1 This is a top view schematic diagram illustrating the ground retaining piles and the tunnel retaining piles in this invention.
[0028] Figure 2 This is a side view schematic diagram illustrating the cut-and-cover section in this invention.
[0029] Figure 3 This is a side view schematic diagram illustrating the pipe curtain and steel pipe columns in this invention.
[0030] Figure 4 This is a schematic diagram illustrating the structure of the transfer trolley in this invention.
[0031] Figure 5 yes Figure 4A magnified view of part A in the middle.
[0032] In the diagram, 1. Ground retaining piles; 2. First open-cut section; 3. Second open-cut section; 4. Tunnel excavation section; 42. Temporary concrete frame; 43. In-tunnel retaining piles; 44. In-tunnel piles; 5. Pipe curtain; 51. Steel pipe column piles; 6. Chassis; 61. Clamping assembly; 611. Lifting component; 612. Adjusting jack; 613. Hydraulic cylinder gripper; 62. Turntable; 621. Support plate; 622. Buckle; 623. Rotating component; 63. Lowering assembly; 631. Winch; 632. Pulley; 633. Pull rope; 8. Running track. Detailed Implementation
[0033] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the invention, and therefore only show the components relevant to the invention.
[0034] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, features defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more. In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly, for example, as a fixed connection, a detachable connection, or an integral connection; as a mechanical connection or an electrical connection; as a direct connection or an indirect connection through an intermediate medium; or as a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.
[0035] This application discloses a method for constructing retaining structures using the tunnel pile method under ground-constrained conditions.
[0036] A method for constructing retaining structures using the tunnel-pile method under confined ground conditions, referring to... Figures 1 to 3 It includes the following steps: Ground pile construction: Ground retaining piles 1 are constructed on the ground. Ground retaining piles 1 are set along the first open-cut section 2 and the second open-cut section 3. Ground retaining piles 1 are also set between the first open-cut section 2, the second open-cut section 3 and the tunnel section 4.
[0037] Shallow foundation pit excavation: Construction of the first open-cut section 2 and the second open-cut section 3. During the excavation of the first open-cut section 2 and the second open-cut section 3, capping beams are constructed to reinforce the sidewalls of the first open-cut section 2 and the second open-cut section 3. By reinforcing the sidewalls of the first open-cut section 2 and the second open-cut section 3 with capping beams, the possibility of collapse in the first open-cut section 2 and the open-cut sections is reduced, thus improving the safety of construction.
[0038] Pipe jacking 5 construction: Support beams for pipe jacking 5 are constructed beneath the running track 8, followed by the construction of pipe jacking 5. During pipe jacking 5 construction, pile foundations are first laid to create the opening for pipe jacking 5. Then, pipe jacking 5 is excavated through the opening, followed by the insertion of the reinforcing cage into pipe jacking 5. Finally, concrete is poured and grout is injected. Pipe jacking 5 reinforces the soil, thereby reducing the possibility of settlement of the running track 8.
[0039] Construction of Cut-and-cover Section 4: Excavation proceeds from the first open-cut section 2 and the second open-cut section 3 towards the operating direction to excavate Cut-and-cover Section 4. Before excavation of Cut-and-cover Section 4, advance pipe roofs are constructed on both sides of Cut-and-cover Section 4. Then, the ground retaining piles 1 are broken through, and cut-and-cover is carried out using the bench method. During the excavation of Cut-and-cover Section 4, a temporary concrete frame 42 is constructed within Cut-and-cover Section 4. The advance pipe roofs and the temporary concrete frame 42 protect Cut-and-cover Section 4, ensuring safety during its construction.
[0040] Construction of piles 44 inside the tunnel: Construct retaining piles 43 inside the tunnel along the edge of the tunnel section 4. The retaining piles 43 inside the tunnel are interlocking piles formed by a combination of bored piles and jet grouting piles. Construct piles 44 inside the tunnel at multiple locations on the ground of the tunnel section 4, and install steel pipe column piles 51 on the piles 44 inside the tunnel.
[0041] During the construction of pile 44 inside the tunnel, a low-clearance rotary drilling rig was used to form the borehole. The reinforcing cage was then transported by a transfer trolley and lowered into the borehole. The reinforcing cage was placed in multiple sections, with adjacent sections welded together. Because the total length of the reinforcing cage exceeded the height of the excavated section 4, the cage was divided into multiple sections and placed into the borehole sequentially. These sections were then welded together to reassemble the cage, thus solving the problem of limited space in the excavated section 4 that hindered the construction of pile 44 inside the tunnel.
[0042] Specifically, refer to Figure 4 and Figure 5The transfer trolley includes a frame 6 and a clamping assembly 61, a steering assembly, and a lowering assembly 63 mounted on the frame 6. The clamping assembly 61 clamps the reinforcing cage, the steering assembly moves the reinforcing cage above the hole, and the lowering assembly 63 lowers the reinforcing cage into the hole. When lowering the reinforcing cage, the clamping assembly 61 clamps the cage, the steering assembly moves the cage above the hole, and the lowering assembly 63 lowers the cage into the hole. At this point, the reinforcing cage is fixed to the hole opening with reinforcing bars. This is the old reinforcing cage. The transfer trolley then moves a new reinforcing cage above the old one and welds them together. The old cage is then released from its fixation. The lowering assembly 63 continues to lower the cage, repeating the above steps until the cage reaches the set length and is positioned at the set location. The frame 6 is also equipped with casters for easy movement.
[0043] More specifically, the clamping assembly 61 includes a lifting component 611, an adjusting jack 612, and a hydraulic cylinder gripper 613. The lifting component 611 is mounted on the frame 6, and its movable end is connected to the adjusting jack 612. The adjusting jack 612 is horizontally positioned, and its movable end is connected to the hydraulic cylinder gripper 613. The hydraulic cylinder gripper 613 facilitates clamping the reinforcing cage. Subsequently, the height of the reinforcing cage is adjusted via the lifting component 611, and the position of the reinforcing cage on the horizontal plane is adjusted via the steering assembly and the adjusting jack 612, thereby facilitating the alignment of the reinforcing cage with the hole in the opening and improving construction efficiency. The lifting component 611 can be a linear module or a jack. The adjusting jack 612 and the hydraulic cylinder gripper 613 are provided in two sets along the vertical direction.
[0044] The steering assembly includes a rotating component 623 and a turntable 62. The rotating component 623 is mounted on the bottom of the frame 6, and the turntable 62 is rotatably connected to the frame 6. The movable end of the rotating component 623 is connected to the turntable 62. The rotating component 623 facilitates driving the turntable 62 to rotate, thereby facilitating the transfer of the reinforcing cage to the top of the hole inside the tunnel. The rotating component 623 can be a stepper motor or a rotary hydraulic cylinder.
[0045] The lowering assembly 63 includes a winch 631, a pulley 632, and a rope 633. The winch 631 is mounted on the frame 6, the pulley 632 is mounted on the movable end of the lifting component 611, one end of the rope 633 is connected to the drum of the winch 631, and the other end passes over the pulley 632 and is connected to the reinforcing cage. The winch 631, rope 633, and pulley 632 work together to facilitate the lowering of the reinforcing cage into the hole. The top of the pulley 632 is enclosed to prevent the rope 633 from disengaging from the pulley 632 when the lifting component 611 rotates.
[0046] The turntable 62 is equipped with a support plate 621, to which a traction rope is connected. A buckle 622 is connected to the traction rope and is used to connect to the rebar cage. When the rebar cage is transported on the frame 6, it is placed horizontally. When the rebar cage needs to be erected, the traction rope and buckle 622 are connected to one end of the rebar cage, and then a pull rope 633 is connected to the other end. The winch 631 pulls the pull rope 633, thereby pulling the rebar cage to rotate around the buckle 622. At this time, the operator can hold the rebar cage to assist in the process. The buckle 622 and traction rope provide a fulcrum for the rebar cage, reducing the possibility of it tipping over during erection. After the rebar cage is erected, the hydraulic cylinder gripper 613 clamps it.
[0047] When lowering the reinforcing cage, the buckle 622 is connected to one end of a reinforcing cage on the frame 6, and then the pull rope 633 is connected to the other end of the reinforcing cage. The winch 631 pulls the pull rope 633, which in turn pulls the reinforcing cage to rotate around the buckle 622. At this time, the operator can hold the reinforcing cage to assist in the process. The buckle 622 and the pull rope provide a fulcrum for the reinforcing cage, reducing the possibility of the reinforcing cage tipping over during the erection process. After the reinforcing cage is erected, the hydraulic cylinder clamp 613 clamps the reinforcing cage. Then, the height of the reinforcing cage is adjusted by the lifting component 611, and the position of the reinforcing cage on the horizontal plane is adjusted by the steering component and the adjusting jack 612, so that the reinforcing cage can be aligned with the position of the hole inside the tunnel. Finally, the winch 631, the pull rope 633 and the pulley 632 work together to lower the reinforcing cage into the hole inside the tunnel.
[0048] Cover plate construction: Construct the pile top cap beam on the steel pipe column pile 51, and install the cover plate on the pile top cap beam.
[0049] Working principle: First, the ground retaining piles 1 are constructed. Then, during the construction of the underground excavation section 4, the tunnel retaining piles 43 are constructed, and the tunnel retaining piles 43 are connected with the ground retaining piles 1 to form a closed retaining pile structure, which ensures the safety of subsequent construction, the stability of the soil around the subway station, and construction efficiency.
[0050] The embodiments described in this specific implementation are preferred embodiments of this application and are not intended to limit the scope of protection of this application. Identical components are represented by the same reference numerals. Therefore, all equivalent changes made to the structure, shape, and principle of this application should be included within the scope of protection of this application.
Claims
1. A method for constructing retaining structures using the tunnel-pile method under confined ground conditions, characterized in that, Includes the following steps: Ground pile construction: Ground retaining piles (1) are constructed on the ground. The ground retaining piles (1) are set along the first open excavation section (2) and the second open excavation section (3). Ground retaining piles (1) are also set between the first open excavation section (2), the second open excavation section (3) and the tunnel section (4). Shallow foundation pit excavation: construction of the first open excavation section (2) and the second open excavation section (3); Pipe curtain (5) construction: construct the pipe curtain (5) support beam under the running track (8), and then construct the pipe curtain (5); Construction of the cut-and-cover section (4): Excavation is carried out from the first open-cut section (2) and the second open-cut section (3) toward the operation to excavate the cut-and-cover section (4); Construction of piles (44) inside the tunnel: construct retaining piles (43) inside the tunnel along the edge of the tunnel section (4), the retaining piles (43) inside the tunnel are connected to the retaining piles (1) on the ground, construct piles (44) inside the tunnel at multiple locations on the ground of the tunnel section (4), and install steel pipe column piles (51) on the piles (44) inside the tunnel. Cover plate construction: Construct the pile top cap beam on the steel pipe column pile (51) and install the cover plate on the pile top cap beam.
2. The method for constructing a retaining structure using the tunnel-pile method under confined ground conditions according to claim 1, characterized in that: During the excavation of the first open-cut section (2) and the second open-cut section (3), the construction cap beam reinforces the side walls of the first open-cut section (2) and the second open-cut section (3).
3. A method for constructing a retaining structure using the tunnel-pile method under confined ground conditions, as described in claim 2, is characterized in that: During the construction of the pipe curtain (5), the piles are first laid to open the hole to form the pipe curtain (5) hole. Then the pipe curtain (5) is excavated in the pipe curtain (5) hole. Then the steel cage is pushed into the pipe curtain (5). Finally, concrete is poured and grouting is carried out.
4. A method for constructing a retaining structure using the tunnel-pile method under confined ground conditions, as described in claim 3, is characterized in that: Before the excavation of the tunnel section (4), advance pipe sheds are constructed on both sides of the tunnel section (4), then the ground retaining piles (1) are broken, and then the tunnel is excavated by step method. During the excavation of the tunnel section (4), a temporary concrete frame (42) is constructed in the tunnel section (4).
5. A method for constructing a retaining structure using the tunnel-pile method under confined ground conditions, as described in claim 4, is characterized in that: During the construction of the tunnel pile (44), a low-clearance rotary drilling rig is used to form the tunnel hole. Then, the steel cage is transported by a transfer trolley and lowered into the tunnel hole. The steel cage is placed in multiple sections, and adjacent sections of the steel cage are welded together.
6. A method for constructing a retaining structure using the tunnel-pile method under confined ground conditions, as described in claim 5, is characterized in that: The transfer trolley includes a frame (6) and a clamping assembly (61), a steering assembly, and a lowering assembly (63) mounted on the frame (6). The clamping assembly (61) is used to clamp the steel cage, the steering assembly is used to transfer the steel cage to the top of the hole, and the lowering assembly (63) is used to lower the steel cage into the hole.
7. A method for constructing a retaining structure using the tunnel-pile method under confined ground conditions, as described in claim 6, is characterized in that: The clamping assembly (61) includes a lifting component (611), an adjusting jack (612), and a hydraulic cylinder gripper (613). The lifting component (611) is mounted on the frame (6). The movable end of the lifting component (611) is connected to the adjusting jack (612). The adjusting jack (612) is horizontally positioned. The movable end of the adjusting jack (612) is connected to the hydraulic cylinder gripper (613).
8. A method for constructing a retaining structure using the tunnel-pile method under confined ground conditions, as described in claim 7, characterized in that: The steering assembly includes a rotating component (623) and a turntable (62). The rotating component (623) is mounted on the bottom of the frame (6), and the turntable (62) is rotatably connected to the frame (6). The movable end of the rotating component (623) is connected to the turntable (62).
9. A method for constructing a retaining structure using the tunnel-pile method under confined ground conditions, as described in claim 8, characterized in that: The lowering assembly (63) includes a winch (631), a pulley (632), and a rope (633). The winch (631) is mounted on the frame (6), the pulley (632) is mounted on the movable end of the lifting component (611), one end of the rope (633) is connected to the drum of the winch (631), and the other end passes around the pulley (632) and is connected to the steel cage.
10. A method for constructing a retaining structure using the tunnel-pile method under confined ground conditions, as described in claim 9, characterized in that: The turntable (62) is provided with a support plate (621), a traction rope is connected to the support plate (621), and a buckle (622) is connected to the traction rope. The buckle (622) is used to connect with the steel cage.