Tunnel construction device and method under soft soil

Abstract

The invention discloses a tunnel construction device and method under soft soil, the device comprises a compaction type separation mechanism which is separated at the position of a tunnel contour line, a plurality of grouting pipes are detachably connected to the compaction type separation mechanism, one end of each grouting pipe extends into the soil at the top of a tunnel, and the other end of each grouting pipe extends into the soil at the bottom of the tunnel. A machine frame connected with the longitudinal driving piece is arranged at the end of the outer side of the compaction type arch separation mechanism, a rotary excavating mechanism is connected to the machine frame through a transmission mechanism, and the machine frame is connected with a circumferential traction mechanism. According to the method, tunnel construction is conducted on a soft soil area through the device, the soft soil is compacted, then reinforcement is conducted in a grouting mode, and a firm supporting structure is formed. The structural strength of soft soil is enhanced, the construction difficulty is reduced, and the construction efficiency, the construction quality and the safety are improved. The method is suitable for the technical field of tunnel construction under soft soil.

Description

Technical Field

[0001] This invention belongs to the technical field of tunnel construction, specifically, it relates to a tunnel construction device and method in soft soil. Background Technology

[0002] Tunnel construction in soft soil environments (such as silty soil, silty clay, sandy soil, peat soil, etc.) is prone to a series of technical challenges and safety risks due to the physical and mechanical properties of the soil itself.

[0003] The low strength and high fluidity of soft soil make it highly susceptible to sudden geological disasters during construction, directly threatening the safety of personnel and equipment. Specifically, soft soil has weak cohesion and a small internal friction angle, lacking self-stabilizing ability after excavation. If support is not timely or its strength is insufficient, the tunnel face is prone to collapse and spalling, and may even cause tunnel arch subsidence and excessive sidewall convergence, leading to overall structural instability. Especially in sandy or silty soils, where there is no interparticle cohesion, collapses may spread in a quicksand-like manner, making the affected area difficult to control. Soft soil has high compressibility, and tunnel excavation will disturb the surrounding soil, causing uneven surface settlement. If the settlement exceeds the warning value, it may cause cracking of surrounding roads, tilting of buildings, and rupture of underground pipelines, triggering a chain reaction of accidents such as fires, water leaks, and power outages.

[0004] The physical properties of soft soil make it difficult to meet tunnel construction quality standards and leave long-term safety hazards. Specifically, the uneven lateral pressure of soft soil can easily lead to elliptical deformation of the tunnel cross-section after excavation. During shield tunneling, uneven soil resistance can cause the shield machine to drift, making it difficult to ensure the accuracy of the tunnel axis and affecting subsequent processes such as track laying and lining installation. The long settlement time of soft soil strata means that the lining structure must withstand uneven soil pressure for a long period, making it prone to circumferential or longitudinal cracks. At the same time, the soil has high permeability; if the lining joints are not properly sealed or the concrete pouring quality is poor, long-term leakage can easily occur, corroding the reinforcing steel and reducing structural durability. Summary of the Invention

[0005] This invention provides a tunnel construction device and method in soft soil, which enhances the structural strength of soft soil, reduces construction difficulty, and improves construction efficiency, quality and safety during construction.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A tunnel construction device in soft soil includes a compaction separation mechanism separated at the tunnel outline. Multiple grouting pipes are detachably connected to the compaction separation mechanism, with one end of each grouting pipe extending into the soil at the top of the tunnel. A frame connected to a longitudinal drive component is provided at the outer end of the compaction arched separation mechanism. A rotary drilling mechanism is connected to the frame via a transmission mechanism, and the frame is also connected to a circumferential traction mechanism.

[0007] Furthermore, the extrusion separation mechanism includes a plurality of extrusion separation components that are hinged in sequence. The outer ends of the plurality of extrusion separation components are connected by an arc-shaped fixing seat. The arc-shaped fixing seat is detachably connected to the frame, and the arc-shaped fixing seat and the plurality of extrusion separation components form an arched support frame.

[0008] Furthermore, the compaction and separation assembly includes a support member and a compaction member that are interlocked with each other. The compaction member contacts the inner wall of the tunnel, and a driving cavity is formed between the support member and the compaction member. A medium inlet connector and a medium outlet connector are constructed on the support member, and both the medium inlet connector and the medium outlet connector are connected to the driving cavity.

[0009] Furthermore, a plurality of elastic connectors are provided in the drive cavity, and the two ends of each elastic connector are respectively connected to the support member and the compaction member.

[0010] Furthermore, a first hinge ear and a second hinge ear are respectively constructed on both sides of the support member. The first hinge ear and the second hinge ear that are close to each other between two adjacent support members are connected to each other by a hinge rod. One end of the hinge rod is detachably connected to the arc-shaped fixed seat.

[0011] Furthermore, multiple first connecting sleeves are spaced apart along the length of the support member, and a second connecting sleeve is constructed on the compaction member at a position corresponding to the first connecting sleeve. The first connecting sleeve and the second connecting sleeve are movably fitted together, forming an assembly channel between them. The grouting pipe is inserted into the soil at the top of the tunnel through the assembly channel.

[0012] Furthermore, an insertion tooth is constructed at the end of the support member away from the arc-shaped fixing seat.

[0013] Furthermore, the rotary drilling mechanism includes a drive motor slidably mounted on the frame along the length of the frame, and a rotary drilling rod is coaxially and detachably connected to the output shaft of the drive motor; the transmission mechanism includes a power motor mounted on the frame, a transmission screw extending along the length of the frame is coaxially mounted on the output shaft of the power motor, and a transmission lug is mounted on the drive motor, with the transmission screw and the transmission lug being threadedly connected.

[0014] Furthermore, the circumferential traction mechanism includes two guide wheels respectively disposed on both sides of the frame, and a winch is disposed below the frame. A first wire rope is wound in the forward direction and a second wire rope is wound in the reverse direction on the winch. The first wire rope is turned by one guide wheel and connected to one side of the frame, and the second wire rope is turned by another guide wheel and connected to the other side of the frame.

[0015] This invention also discloses a method for tunnel construction in soft soil, which uses the aforementioned tunnel construction device for soft soil to construct the tunnel, including the following steps: Step 1. Install the compaction separator at the front of the tunnel construction vehicle and drive the tunnel construction vehicle toward the area to be excavated in the tunnel, so that the compaction separator is gradually inserted into the soil along the tunnel outline. Step 2. After the insertion reaches the predetermined depth, install the longitudinal drive component on the tunnel construction vehicle and connect the circumferential traction mechanism to the frame; Step 3. Control the rotary drilling mechanism, transmission mechanism and circumferential traction mechanism to work together to rotary excavate and remove the soil inside the compaction separator; after completion, dismantle the rotary drilling mechanism. Step 4. Connect the frame to the compaction separation mechanism, control the compaction separation mechanism to perform the compaction action, compact the soil on the outside of the compaction separation mechanism, and at the same time, control the circumferential traction mechanism to move. The circumferential traction mechanism drives the compaction separation mechanism to rotate circumferentially by a certain angle through the frame, so that a surface grouting cavity is formed between the compaction separation mechanism and the outer soil. Step 5. Insert multiple grouting pipes into the soil outside the compaction separation mechanism at intervals through the compaction separation mechanism; Step 6. Grouting is carried out through each grouting pipe. The concrete slurry enters the soil outside the compaction separation mechanism and gradually seeps into the surface grouting cavity until the surface grouting cavity is full. Step 7. After the concrete slurry has solidified, remove the compaction separation mechanism.

[0016] The technological advancements achieved by this invention compared to existing technologies, due to the aforementioned structure, lie in the following: The compaction-type separating mechanism of this invention, after being inserted into the soft soil layer along the tunnel outline, directly forms an arched support skeleton, replacing the traditional excavation followed by support method. This avoids problems such as tunnel face collapse and quicksand spread caused by the lack of self-stabilizing capacity after soft soil excavation. It conforms to the tunnel outline, forming continuous lateral constraints, effectively resisting the lateral pressure of the soft soil and preventing excessive tunnel arch subsidence and sidewall convergence. On one hand, the compaction action of the compaction-type separating mechanism compresses the pores of the outer soft soil, improving soil density and cohesion; on the other hand, concrete grout is injected into the soil through grouting pipes. After the grout seeps into the soil pores and solidifies, a dual reinforcement effect of compaction and grouting is achieved, transforming loose soft soil into a robust composite support structure, fundamentally reducing the risk of secondary disasters such as water inrush, mudslides, and excessive surface subsidence. The rotary drilling mechanism, transmission mechanism, and circumferential traction mechanism work together to excavate only the soil inside the separation mechanism, avoiding large-scale disturbance of the surrounding soil layers. At the same time, the circumferential traction mechanism controls the posture of the frame and separation mechanism through steel wire ropes and guide wheels to prevent equipment deviation caused by uneven soil resistance during construction, thereby reducing the impact on surrounding underground pipelines and buildings.

[0017] The arched support frame formed by the compaction-type separation mechanism of this invention provides a precise contour reference for tunnel excavation, avoiding elliptical deformation of the cross-section caused by uneven lateral pressure in soft soil. The rotary drilling mechanism slides precisely along the frame, ensuring consistency in the depth and range of rotary drilling, effectively controlling tunnel axis deviation, and laying a good foundation for subsequent track laying, lining installation, and other processes. The composite support structure formed by grouting can withstand uneven soil pressure for a long time, reducing the stress load on the lining structure and preventing circumferential or longitudinal cracks in the lining. At the same time, the grouting layer can seal soil pores, reduce the risk of groundwater seepage, prevent leakage at lining joints and steel corrosion, and extend the service life of the tunnel. This device integrates contour positioning, soil separation, rotary drilling, compaction reinforcement, and grouting into a single operation, eliminating the need for complex ground pretreatment processes such as deep mixing piles and high-pressure jet grouting piles, significantly shortening the construction cycle. All components of the compaction separation mechanism, including the grouting pipe, rotary drilling rod, and drive motor, are detachable, facilitating equipment transportation, installation, and maintenance. For tunnels with different cross-sectional dimensions, the support frame specifications can be adjusted by increasing or decreasing the number of components that make up the compaction separation mechanism, resulting in strong adaptability and further improving construction efficiency.

[0018] In summary, this invention not only enhances the structural strength of soft soil and ensures long-term safety during construction and tunnel operation, but also significantly improves construction efficiency and optimizes project quality through process integration and automated collaboration, while reducing construction difficulty and overall costs, providing efficient and reliable support for soft soil tunnel construction. Attached Figure Description

[0019] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof.

[0020] In the attached diagram: Figure 1 This is a schematic diagram of the structure of an embodiment of the present invention; Figure 2 This is a schematic diagram of the extrusion-type partition mechanism according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the structure of the extrusion separation component in the extrusion separation mechanism according to an embodiment of the present invention; Figure 4 This is a cross-sectional view of the extrusion separation component in the extrusion separation mechanism according to an embodiment of the present invention; Figure 5 for Figure 4 Enlarged view of the structure at part A in the middle; Figure 6 for Figure 4 Enlarged view of the structure of part B in the middle; Figure 7This is a schematic diagram of the disassembled structure of the extrusion separation component in the extrusion separation mechanism according to an embodiment of the present invention; Figure 8 for Figure 7 A schematic diagram of the structure shown from another angle; Figure 9 This is a schematic diagram of the connection between the longitudinal drive component, frame, transmission mechanism, rotary drilling mechanism and circumferential traction mechanism in an embodiment of the present invention; Figure 10 This is a schematic diagram of the connection between the extrusion-type separation mechanism and multiple grouting pipes in an embodiment of the present invention.

[0021] Components labeled: 100-Extrusion partition mechanism, 101-Support member, 102-First hinge ear, 103-Second hinge ear, 104-First connecting sleeve, 105-Assembly channel, 106-Spring seat, 107-Connecting spring, 108-Connecting bolt, 109-Lower cavity, 110-Insertion tooth, 111-Extrusion member, 112-Upper cavity, 113-Second connecting sleeve, 114-Reinforcing rib, 115-Media inlet connector, 116-Media outlet connector, 117-Drive cavity, 200-Hinge Rod, 300-arc-shaped fixed seat, 301-connecting column, 400-longitudinal drive component, 500-frame, 501-frame body, 502-slide rail, 600-rotary drilling mechanism, 601-drive motor, 602-rotary drilling rod, 603-transmission ear, 700-transmission mechanism, 701-power motor, 702-transmission screw, 800-circumferential traction mechanism, 801-winner, 802-guide wheel, 803-first wire rope, 804-second wire rope, 900-grouting pipe, 901-grouting hole. Detailed Implementation

[0022] The preferred embodiments of the present invention will now be described with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.

[0023] This invention discloses a tunnel construction device in soft soil, such as... Figures 1-10 As shown, the system includes a compaction separation mechanism 100, a longitudinal drive component 400, a frame 500, a transmission mechanism 700, a rotary drilling mechanism 600, and a circumferential traction mechanism 800. The compaction separation mechanism 100 is positioned along the tunnel outline. Multiple grouting pipes 900 are detachably connected to the compaction separation mechanism 100, with one end of each grouting pipe 900 extending into the soil at the tunnel ceiling. The frame 500 is located at the outer end of the compaction arched separation mechanism and is connected to the longitudinal drive component 400. The rotary drilling mechanism 600 is mounted on the frame 500 and is connected to the transmission mechanism 700. The frame 500 is also connected to the circumferential traction mechanism 800. The longitudinal drive component 400 is typically a hydraulic cylinder.

[0024] The working principle and advantages of this invention are as follows: The compaction-type separating mechanism 100 of this invention, after being inserted into the soft soil layer along the tunnel outline, directly forms an arched support skeleton, replacing the traditional excavation followed by support mode. This avoids problems such as tunnel face collapse and quicksand spread caused by the lack of self-stabilizing ability after soft soil excavation. It can conform to the tunnel outline, forming continuous lateral constraints, effectively resisting the lateral pressure of soft soil, and preventing tunnel arch subsidence and excessive sidewall convergence. On the one hand, the compaction action of the compaction-type separating mechanism 100 compresses the pores of the outer soft soil, improving soil density and cohesion; on the other hand, concrete grout is injected into the soil through the grouting pipe 900. After the grout seeps into the soil pores, it solidifies, forming a dual reinforcement effect of compaction + grouting, transforming loose soft soil into a solid composite support structure, fundamentally reducing the risk of secondary disasters such as water inrush, mudslides, and excessive surface subsidence. The rotary drilling mechanism 600, the transmission mechanism 700, and the circumferential traction mechanism 800 work together to excavate only the soil inside the separation mechanism, avoiding large-scale disturbance of the surrounding soil layers. At the same time, the circumferential traction mechanism 800 controls the posture of the frame 500 and the separation mechanism through steel wire ropes and guide wheels 802 to prevent equipment deviation caused by uneven soil resistance during construction, thereby reducing the impact on surrounding underground pipelines and buildings.

[0025] The arched support frame formed by the compaction and separation mechanism 100 of this invention provides a precise contour reference for tunnel excavation, avoiding elliptical deformation of the cross-section caused by uneven lateral pressure in soft soil. The rotary drilling mechanism 600 slides precisely along the frame 500, ensuring consistency in the depth and range of rotary drilling, effectively controlling tunnel axis deviation, and laying a good foundation for subsequent track laying, lining installation, and other processes. The composite support structure formed by grouting can withstand uneven soil pressure for a long time, reducing the stress load on the lining structure and preventing circumferential or longitudinal cracks in the lining. At the same time, the grouting layer can seal soil pores, reduce the risk of groundwater seepage, prevent leakage at lining joints and steel corrosion, and extend the service life of the tunnel. This device integrates contour positioning, soil separation, rotary drilling, compaction and reinforcement, and grouting into a single operation, eliminating the need for complex ground pretreatment processes such as deep mixing piles and high-pressure jet grouting piles, significantly shortening the construction cycle. All components of the compaction separation mechanism 100, the grouting pipe 900, the rotary drilling rod 602, and the drive motor 601 are detachable, which facilitates equipment transportation, installation, and maintenance. For tunnels with different cross-sectional dimensions, the specifications of the support frame can be adjusted by increasing or decreasing the number of components that make up the compaction separation mechanism 100, which has strong adaptability and further improves construction efficiency.

[0026] In summary, this invention not only enhances the structural strength of soft soil and ensures long-term safety during construction and tunnel operation, but also significantly improves construction efficiency and optimizes project quality through process integration and automated collaboration, while reducing construction difficulty and overall costs, providing efficient and reliable support for soft soil tunnel construction.

[0027] As a preferred embodiment of the present invention, such as Figure 2 As shown, the compaction separation mechanism 100 includes multiple compaction separation components hinged sequentially. The outer ends of these compaction separation components are connected via an arc-shaped fixing seat 300. Two connecting columns 301 are threaded onto the arc-shaped fixing seat 300. These two connecting columns 301 are detachably connected to the frame 500, and the arc-shaped fixing seat 300 and the multiple compaction separation components form an arched support frame. During rotary drilling, the connecting columns 301 are disconnected from the frame 500 to facilitate the adjustment of the frame 500's angle and drive the rotary drilling mechanism 600 to rotate along the tunnel's outline, achieving rotary drilling of the soil inside the compaction separation mechanism 100 without dead angles.

[0028] In this embodiment, the compaction separation mechanism 100 is composed of multiple sequentially hinged compaction separation components, which, together with the arc-shaped fixed seat 300, form an arched support frame. This structure perfectly conforms to the arc-shaped contour of the tunnel. During the rotary drilling stage, when the connecting column 301 is disconnected from the frame 500, the frame 500 can drive the rotary drilling mechanism 600 to rotate flexibly along the arch contour. The rotary drilling mechanism 600 can cover all areas inside the compaction separation mechanism 100, including the arch crown, arch waist, arch foot, and other arc-shaped dead corners that are difficult for traditional straight-line rotary drilling equipment to reach, avoiding residual soil due to incomplete excavation, reducing subsequent cleaning procedures, and improving construction efficiency. The arc-shaped fixed seat 300 and the frame 500 are connected by a detachable connection via the connecting column 301. After the connection is removed, the frame 500 is not fixed and can flexibly adjust the angle of the rotary drilling mechanism 600 (such as rotating clockwise / counterclockwise along the arch contour, or fine-tuning the tilt angle) according to the tunnel cross-section size and rotary drilling depth requirements. Even when faced with complex strata where soft soil is unevenly distributed, the rotary drilling rig 600 can be adjusted by angle to target difficult-to-excavate areas, thus improving construction adaptability.

[0029] The modular design of the sequentially hinged compaction and separation components in this embodiment provides a modular advantage: if the tunnel cross-sectional dimensions change, the span and curvature of the arch support frame can be adjusted by increasing or decreasing the number of compaction and separation components; simultaneously, the detachable connecting column 301 and compaction and separation components facilitate individual replacement of damaged parts without requiring replacement of the entire mechanism, reducing equipment maintenance costs and minimizing construction downtime. The rotary drilling mechanism 600 rotates uniformly along the arch contour, distributing the force evenly on the inner soil and avoiding excessive local excavation force that could disturb the outer soft soil; at the same time, the compaction effect of the arch support frame on the outer soil has already increased the soil density in advance, further reducing the compression deformation of the surrounding soil during rotary drilling, reducing surface settlement, and protecting the safety of surrounding buildings and underground pipelines.

[0030] As a preferred embodiment of the present invention, such as Figures 3-8 As shown, the compaction and separation assembly includes a support member 101 and a compaction member 111 that are interlocked. The compaction member 111 contacts the inner wall of the tunnel. A lower cavity 109 is formed at the upper end of the support member 101, and an upper cavity 112 is formed at the lower end of the compaction member 111. When the support member 101 and the compaction member 111 are assembled together, the lower cavity 109 and the upper cavity 112 form a complete drive cavity 117. A medium inlet connector 115 and a medium outlet connector 116 are constructed on the support member 101, and both the medium inlet connector 115 and the medium outlet connector 116 communicate with the drive cavity 117. A plurality of elastic connectors are provided in the drive cavity 117, and the two ends of each elastic connector are connected to the support member 101 and the compaction member 111, respectively. Specifically, the elastic connector includes a connecting spring 107 and a spring seat 106. The spring seat 106 is detachably connected to the support member 101 via a connecting bolt 108. The lower end of the connecting spring 107 is connected to the spring seat 106, and the upper end of the connecting spring 107 is connected to the compacting member 111. A first hinge ear 102 and a second hinge ear 103 are respectively constructed on both sides of the support member 101. The first hinge ears 102 and the second hinge ears 103 of adjacent support members 101 are connected to each other via a hinge rod 200, one end of which is detachably connected to the arc-shaped fixing seat 300.

[0031] In this embodiment, the drive cavity 117, formed by the fastening of the support member 101 and the compaction member 111, is filled with a pressurized medium such as hydraulic oil or compressed air through the medium inlet connector 115. This allows for precise control of the pressure within the cavity, propelling the compaction member 111 to apply a uniform and adjustable compressive force to the outer soft soil. For soft soils of varying densities, such as silty soil requiring low-pressure, slow compaction and sandy soil requiring high-pressure, strong compaction, the compaction force can be adjusted by regulating the medium pressure. This avoids insufficient compaction leading to incomplete reinforcement or excessive compaction causing soil collapse, achieving on-demand compaction and significantly improving the density and structural strength of the soft soil. The connecting spring 107 within the drive cavity 117 is connected to the support member 101 and the compaction member 111 via the spring seat 106, providing elastic cushioning during the compaction process. When soft soil contains localized hard interlayers or cavities, uneven stress on the compaction component 111 will compress or stretch the connecting spring 107, automatically adjusting the displacement of the compaction component 111 to ensure it remains in contact with the tunnel wall, preventing localized under-compaction or excessive compression. This flexible adaptability solves the problem of traditional rigid compaction mechanisms being unable to adapt to the unevenness of soft soil, ensuring the integrity of the compaction reinforcement. The support member 101 and the compaction member 111 are interlocked (a sealing ring is provided at the interlocking point to prevent the medium from leaking out from the assembly point), which not only seals the drive cavity 117, but also forms a dual rigid structure in which the support member 101 bears the load and the compaction member 111 performs the function. The support member 101 is connected to the adjacent compaction partition component through the first hinge ear 102 and the second hinge ear 103, bearing the vertical and lateral pressure of the overall arched support frame. The compaction member 111 is in direct contact with the soil, transmitting the compressive force and preventing soil collapse. The two work together to improve the deformation resistance of the component and prevent the mechanism from cracking or misaligning due to the high lateral pressure of soft soil. The pressure regulation of the drive cavity 117 and the buffering effect of the elastic connector ensure that the force exerted by the compaction member 111 on the soft soil is evenly distributed, avoiding local excessive compression that leads to soil particle loss or local insufficient compression that leaves loose areas. The soil structure after uniform compaction is more stable, which provides a uniform foundation for the composite support layer formed by subsequent grouting, reduces uneven penetration of grout, and avoids grouting voids.

[0032] In this embodiment, the first hinge ears 102 and the second hinge ears 103 on both sides of the support member 101 are connected in series by hinge rods 200, and one end of the hinge rods 200 is detachably connected to the arc-shaped fixing seat 300, so that multiple compaction and separation components form a continuous arched support skeleton. This structure can evenly distribute the stress of the tunnel outline to each compaction and separation component, avoiding the instability of the arched support skeleton caused by local stress concentration; at the same time, the arched support skeleton itself has excellent anti-collapse performance, which can effectively resist the radial pressure of soft soil, providing a stable safety barrier for the inner rotary drilling operation and eliminating risks such as face spalling and arch subsidence. Adjacent compaction and separation components are connected by hinge rods 200, and the hinge rods 200 are detachable from the arc-shaped fixing seat 300. The number of compaction and separation components can be flexibly increased or decreased according to the tunnel cross-section size. For example, fewer compaction and separation components can be added for small cross-section tunnels and more compaction and separation components can be added for large cross-section tunnels, adapting to different construction scenarios without the need for customized special equipment, thus improving equipment reuse rate. The snap-fit ​​structure of the support 101 and the compaction 111 simplifies the assembly process, eliminating the need for complex welding or casting, and facilitating rapid assembly before construction and disassembly and transportation after construction.

[0033] As a preferred embodiment of the present invention, such as Figure 4 , Figure 5 , Figure 7 , Figure 8 , Figure 10 As shown, multiple first connecting sleeves 104 are spaced apart along the length of the support member 101. A second connecting sleeve 113 is constructed on the compaction member 111 at a position corresponding to the first connecting sleeves 104. The first connecting sleeves 104 and the second connecting sleeves 113 are movably fitted together, forming an assembly channel 105 between them. The grouting pipe 900 is inserted into the soil at the top of the tunnel through the assembly channel 105. Furthermore, reinforcing ribs 114 are symmetrically constructed on the outer wall of the second connecting sleeve 113. An insertion tooth 110 is constructed at the end of the support member 101 away from the arc-shaped fixing seat 300.

[0034] In this embodiment, the assembly channel 105 formed by the first connecting sleeve 104 of the support member 101 and the second connecting sleeve 113 of the compaction member 111 provides strict directional constraints for the grouting pipe 900. When inserting the grouting pipe 900, no additional measurement or positioning is required; it can be directly inserted along the channel, precisely aligning with the soil at the top of the tunnel (the most easily collapsed area in soft soil, requiring key reinforcement). This avoids deviations in the insertion position of the grouting pipe 900 due to human error. If it deviates from the reinforcement area, resulting in unreinforced local soil, or if inserted too deeply / too shallowly, it affects the grout diffusion range. This directionality is crucial for soft soil reinforcement, ensuring that the grout accurately acts on key parts of the tunnel outline, forming a uniform composite support layer and effectively resisting the risk of arch subsidence. Furthermore, grouting holes 901 are evenly distributed on the grouting pipe 900, ensuring comprehensive grouting.

[0035] Soft soil is prone to local deformation during compaction or rotary drilling. The movable design of the first connecting sleeve 104 and the second connecting sleeve 113 allows for a certain relative displacement space. When the compaction component 111 slightly shifts due to soil pressure, the second connecting sleeve 113 can adjust its position synchronously with the compaction component 111, avoiding bending or breakage of the grouting pipe 900 due to rigid connection. At the same time, the assembly channel 105 always maintains a wrapping constraint on the grouting pipe 900, preventing the grouting pipe 900 from shaking due to grout pressure impact during grouting, ensuring stable grout injection, and reducing grout leakage and runoff problems. Multiple first connecting sleeves 104 are constructed at intervals along the length of the support component 101, corresponding to multiple independent assembly channels 105, which can be inserted into multiple grouting pipes 900 for synchronous or segmented grouting. The spaced distribution of multiple grouting pipes 900 allows the concrete grout to spread evenly in the tunnel top and surrounding soil, avoiding the problems of concentrated grout accumulation and local voids caused by single-pipe grouting. Especially for soft soils with uneven permeability, such as sandy soil and silty soil, uniform grouting can ensure that the soil pores are fully filled, greatly improve the strength of the reinforced structure, and reduce the risk of water inrush and mud inrush.

[0036] In this embodiment, the reinforcing rib 114 and the compaction component 111 are integrated, which not only improves the strength of the second connecting sleeve 113 itself, but also enhances the connection stability between the second connecting sleeve 113 and the compaction component 111: preventing the second connecting sleeve 113 from separating from the compaction component 111 due to long-term stress, ensuring the structural integrity of the entire compaction and separation assembly, and avoiding safety accidents such as misalignment of the grouting pipe 900 and soil collapse caused by the second connecting sleeve 113 falling off.

[0037] In this embodiment, when the compaction separator 100 is inserted into soft soil along the tunnel outline, the insertion teeth 110 can penetrate local hard interlayers in the soil or disperse the cohesion between soil particles, significantly reducing the resistance when the support member 101 is inserted. Compared to toothless structures that rely on tunnel construction vehicles for forceful insertion, the insertion teeth 110 allow the compaction separator 100 to advance more easily along the designed outline, reducing the power consumption of the tunnel construction vehicle and preventing the mechanism from shifting due to forced insertion, thus improving insertion positioning efficiency. After the insertion teeth 110 are inserted into the soft soil, the tooth-like structure can form an interlocking action with the soil, preventing the compaction separator component from slipping due to the high fluidity of the soil in the early stages of insertion, providing stable initial support for subsequent rotary drilling and compaction operations. Especially in soft soils with high fluidity such as sandy soil, the interlocking action of the insertion teeth 110 can prevent the mechanism from rebounding after insertion, ensuring that the arched support frame quickly forms a stable outline constraint, creating safe conditions for rotary drilling and removal of the inner soil, and reducing rework and adjustment time caused by mechanism slippage.

[0038] As a preferred embodiment of the present invention, such as Figure 1 , Figure 9As shown, the frame 500 includes a frame body 501, on which a slide rail 502 extending along its length is formed. The rotary drilling mechanism 600 includes a drive motor 601 and a rotary drill rod 602. The drive motor 601 is slidably mounted on the slide rail 502 of the frame body 501 and can slide along the length of the frame body 501. The rotary drill rod 602 is detachably connected to the output shaft of the drive motor 601, and the axis of the rotary drill rod 602 coincides with the axis of the output shaft of the drive motor 601. The transmission mechanism 700 includes a power motor 701 mounted on the frame 500. A transmission screw 702 is coaxially mounted on the output shaft of the power motor 701, and the transmission screw 702 extends along the length of the frame 500. A transmission lug 603 is mounted on the drive motor 601, and the transmission screw 702 is threadedly connected to the transmission lug 603. The circumferential traction mechanism 800 of this embodiment includes two guide wheels 802 respectively disposed on both sides of the frame 500. A winch 801 is disposed below the frame 500. A first wire rope 803 is wound forward on the winch 801, and a second wire rope 804 is wound in the reverse direction. The first wire rope 803 is turned by one guide wheel 802 and connected to one side of the frame 500. The second wire rope 804 is turned by the other guide wheel 802 and connected to the other side of the frame 500.

[0039] In this embodiment, the slide rail 502 of the frame 501 provides directional constraint along the length of the drive motor 601, preventing the drive motor 601 from deviating during sliding. The transmission mechanism 700 drives the transmission screw 702 to rotate through the power motor 701. The screw 702 engages with the transmission lug 603 of the drive motor 601, converting the rotational motion into the linear motion of the drive motor 601. This transmission method has the advantages of uniform speed, stability, and high displacement accuracy, and can precisely control the drilling depth of the rotary drilling rod 602 (such as controlling the advance per cycle according to design requirements) and the lateral movement range. Given the characteristics of soft soil being easily mobile and lacking self-stabilizing ability after excavation, precise rotary drilling control can avoid soil collapse caused by over-excavation or subsequent cleaning problems caused by under-excavation and residual soil, ensuring that the tunnel cross-sectional dimensions and axis deviation strictly meet the design standards, laying the foundation for subsequent lining installation.

[0040] In this embodiment, the circumferential traction mechanism 800, through the coordinated action of the winch 801 forward winding of the first wire rope 803 and reverse winding of the second wire rope 804, combined with the steering action of the guide wheels 802 on both sides, can drive the frame 500 and the rotary drilling mechanism 600 to rotate flexibly along the tunnel outline. When it is necessary to excavate the arched areas such as the tunnel crown and arch waist, the rotation angle of the frame 500 can be controlled by adjusting the winding and unwinding lengths of the first wire rope 803 and the second wire rope 804, so that the rotary drilling rod 602 can cover all areas inside the compaction separation mechanism 100, completely solving the problem that traditional linear rotary drilling equipment cannot reach curved dead corners. This flexibility is crucial for soft soil tunnels, as it can avoid uneven stress on the support structure caused by residual soil in the excavation dead corners, reducing the risk of subsequent settlement.

[0041] In this embodiment, the drive motor 601 of the rotary drilling mechanism 600 is slidably mounted on the slide rail 502. The power motor 701 and transmission screw 702 of the transmission mechanism 700 are independently mounted on the frame 500. The guide wheel 802 and winch 801 of the circumferential traction mechanism 800 are detachably connected to the frame 500. The modular design of each component facilitates rapid assembly after individual transportation to the construction site, making it particularly suitable for scenarios where tunnel construction sites are narrow and large equipment is difficult to access. When a component malfunctions, it can be disassembled and repaired or replaced individually without disassembling the entire frame 500, reducing construction interruption time and improving equipment maintenance efficiency.

[0042] This invention also discloses a method for tunnel construction in soft soil, which uses the aforementioned tunnel construction device for soft soil to construct the tunnel, including the following steps: Step 1. Install the compaction separator 100 at the front end of the tunnel construction vehicle and drive the tunnel construction vehicle toward the area to be excavated in the tunnel, so that the compaction separator 100 is gradually inserted into the soil along the tunnel outline. Step 2. After the insertion reaches the predetermined depth, install the longitudinal drive component 400 on the tunnel construction vehicle and connect the circumferential traction mechanism 800 to the frame 500; Step 3. Control the rotary drilling mechanism 600, transmission mechanism 700 and circumferential traction mechanism 800 to work together to rotary excavate and remove the soil inside the compaction separation mechanism 100; after completion, dismantle the rotary drilling mechanism 600. Step 4. Connect the frame 500 to the compaction separation mechanism 100, control the compaction separation mechanism 100 to perform compaction action, compact the soil on the outside of the compaction separation mechanism 100, and at the same time, control the circumferential traction mechanism 800 to move. The circumferential traction mechanism 800 drives the compaction separation mechanism 100 to rotate circumferentially by a certain angle through the frame 500, so that a surface grouting cavity is formed between the compaction separation mechanism 100 and the outer soil. Step 5. Insert multiple grouting pipes 900 into the soil outside the compaction separation mechanism 100 at intervals through the compaction separation mechanism 100. Step 6. Grouting is carried out through each grouting pipe 900. The concrete slurry enters the soil outside the compaction separation mechanism 100 and gradually seeps into the surface grouting cavity until the surface grouting cavity is full. Step 7. After the concrete slurry has solidified, remove the compaction separation mechanism 100.

[0043] In step 1 of this invention, the compaction separator 100 is inserted into the soft soil along the tunnel outline to directly form an arched protective barrier, replacing the traditional temporary support mode after excavation. Soft soil lacks self-stabilizing capacity before excavation. This step, through the insertion of the compaction separator 100, pre-constrains soil displacement, preventing sudden accidents such as quicksand spread and arch collapse during tunnel face excavation, thus establishing a safe framework for subsequent operations. For example, the insertion teeth 110 are designed to quickly penetrate the soil, ensuring that the compaction separator 100 is accurately positioned along the designed outline, reducing soil disturbance during insertion.

[0044] In step 4, the compaction action compresses the pores of the outer soft soil, increasing soil density and cohesion, and reducing the risk of soil collapse before grouting. The circumferential traction mechanism 800 drives the mechanism to rotate, coordinating with the compaction action of the compaction-type separating mechanism 100, ensuring that the outer side of the area separated by the compaction-type separating mechanism 100 is compacted without dead angles, forming a surface grouting cavity. This provides a fixed filling space for the grout, preventing irregular diffusion of the grout and thus avoiding reinforcement failure. This combination of physical compaction and cavity grout storage reduces the risk of water inrush and mud inrush from the root; especially for highly permeable sandy soil, compaction reduces pore water pressure, while the grouting cavity ensures that the grout forms a continuous impermeable layer.

[0045] In step 6, the concrete grout first penetrates into the pores of the compacted soil and then fills the surface grouting cavity, forming a double-layer structure of deep penetration reinforcement and continuous surface support: on the one hand, the penetration grouting solves the problem of loose soft soil particles and improves the overall strength; on the other hand, the cavity filling ensures that a complete protective layer is formed around the tunnel outline, avoiding uneven stress caused by local voids and reducing the risk of lining cracks and leakage.

[0046] This invention allows the compaction-type separation mechanism 100 to be removed only after the concrete grout has solidified to form a robust composite support layer. This ensures that the reinforced structure has independent load-bearing capacity and avoids premature removal that could lead to soil instability. Compared to traditional methods of dismantling and supporting simultaneously, this invention completely eliminates safety risks during the dismantling process and guarantees the long-term stability of the tunnel structure.

[0047] The construction method of this invention, through a standardized process of contour constraint, precise excavation, and layered reinforcement, deeply matches the functions of each component of the device with the characteristics of soft soil. This not only constructs a comprehensive safety protection system but also ensures the quality and precision of the tunnel. Simultaneously, it improves efficiency and reduces costs through process integration and flexible adaptation. Its core advantage lies in using device functions to support process optimization, and using process optimization to solve the pain points of soft soil, providing a safe, efficient, and reliable integrated solution for soft soil tunnel construction.

[0048] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A tunnel construction device for soft soil, characterized in that: The system includes a compaction separation mechanism located at the tunnel outline. Multiple grouting pipes are detachably connected to the compaction separation mechanism, with one end of each grouting pipe extending into the soil at the top of the tunnel. A frame connected to a longitudinal drive component is provided at the outer end of the compaction arched separation mechanism. A rotary drilling mechanism is connected to the frame via a transmission mechanism, and the frame is also connected to a circumferential traction mechanism.

2. The tunnel construction device under soft soil as described in claim 1, characterized in that: The extrusion separation mechanism includes multiple extrusion separation components that are hinged in sequence. The outer ends of the multiple extrusion separation components are connected by an arc-shaped fixing seat. The arc-shaped fixing seat is detachably connected to the frame, and the arc-shaped fixing seat and the multiple extrusion separation components form an arched support frame.

3. The tunnel construction device under soft soil as described in claim 2, characterized in that: The compaction and separation assembly includes a support member and a compaction member that are interlocked with each other. The compaction member is in contact with the inner wall of the tunnel, and a driving cavity is formed between the support member and the compaction member. A medium inlet connector and a medium outlet connector are constructed on the support member, and both the medium inlet connector and the medium outlet connector are connected to the driving cavity.

4. The tunnel construction device under soft soil as described in claim 3, characterized in that: Multiple elastic connectors are provided inside the drive cavity, and the two ends of each elastic connector are connected to the support member and the compaction member, respectively.

5. The tunnel construction device under soft soil as described in claim 3, characterized in that: A first hinge lug and a second hinge lug are respectively constructed on both sides of the support member. The first hinge lug and the second hinge lug that are close to each other between two adjacent support members are connected to each other by a hinge rod. One end of the hinge rod is detachably connected to the arc-shaped fixed seat.

6. The tunnel construction device under soft soil as described in claim 3, characterized in that: Multiple first connecting sleeves are constructed at intervals along the length of the support member, and a second connecting sleeve is constructed on the compaction member at a position corresponding to the first connecting sleeve. The first connecting sleeve and the second connecting sleeve are movably fitted together, forming an assembly channel between them. The grouting pipe is inserted into the soil at the top of the tunnel through the assembly channel.

7. The tunnel construction device under soft soil as described in claim 3, characterized in that: An insertion tooth is provided at the end of the support member away from the arc-shaped fixing seat.

8. The tunnel construction device under soft soil as described in claim 1, characterized in that: The rotary drilling mechanism includes a drive motor slidably mounted on the frame along the length of the frame, and a rotary drilling rod coaxially and detachably connected to the output shaft of the drive motor; the transmission mechanism includes a power motor mounted on the frame, a transmission screw extending along the length of the frame coaxially mounted on the output shaft of the power motor, and a transmission lug mounted on the drive motor, with the transmission screw and transmission lug being threadedly connected.

9. A tunnel construction device for soft soil as described in claim 1, characterized in that: The circumferential traction mechanism includes two guide wheels located on both sides of the frame. A winch is installed below the frame. A first wire rope is wound in the forward direction and a second wire rope is wound in the reverse direction on the winch. The first wire rope is turned by one guide wheel and connected to one side of the frame. The second wire rope is turned by another guide wheel and connected to the other side of the frame.

10. A method for tunnel construction in soft soil, characterized in that, The tunnel construction device for soft soil as described in any one of claims 1-9 is used to construct a tunnel, comprising the following steps: Step 1. Install the compaction separator at the front of the tunnel construction vehicle and drive the tunnel construction vehicle toward the area to be excavated in the tunnel, so that the compaction separator is gradually inserted into the soil along the tunnel outline. Step 2. After the insertion reaches the predetermined depth, install the longitudinal drive component on the tunnel construction vehicle and connect the circumferential traction mechanism to the frame; Step 3. Control the rotary drilling mechanism, transmission mechanism and circumferential traction mechanism to work together to rotary excavate and remove the soil inside the compaction separator; after completion, dismantle the rotary drilling mechanism. Step 4. Connect the frame to the compaction separation mechanism, control the compaction separation mechanism to perform the compaction action, compact the soil on the outside of the compaction separation mechanism, and at the same time, control the circumferential traction mechanism to move. The circumferential traction mechanism drives the compaction separation mechanism to rotate circumferentially by a certain angle through the frame, so that a surface grouting cavity is formed between the compaction separation mechanism and the outer soil. Step 5. Insert multiple grouting pipes into the soil outside the compaction separation mechanism at intervals through the compaction separation mechanism; Step 6. Grouting is carried out through each grouting pipe. The concrete slurry enters the soil outside the compaction separation mechanism and gradually seeps into the surface grouting cavity until the surface grouting cavity is full. Step 7. After the concrete slurry has solidified, remove the compaction separation mechanism.

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