High-filling open cut tunnel anti-sedimentation mechanism based on pile-slab structure and construction method of high-filling open cut tunnel anti-sedimentation mechanism

Abstract

The invention relates to a high-filling open cut tunnel anti-sedimentation mechanism based on a pile-slab structure and a construction method thereof, and relates to the technical field of road traffic safety. The anti-sedimentation mechanism comprises an open cut tunnel structure, and a first grouting pipe is buried on the outer side of the open cut tunnel structure and located at the bottom of the open cut tunnel structure; a second grouting pipe communicated with the first grouting pipe is arranged in the internal space of the open cut tunnel structure; a grout outlet is formed in the first grouting pipe, and a grouting opening is formed in the second grouting pipe; the gravel isolation belts are distributed on the two sides of the open cut tunnel structure in the transverse direction, and the gravel isolation belts and the open cut tunnel structure are arranged at intervals. The gravel isolation belt reduces the influence of additional stress on the tunnel structure, the grouting pipe system timely solves the problem of plate bottom void, structural stress concentration is avoided, the tunnel structure is in a more stable stress state in the operation process, the overall stability and the bearing capacity of the structure are improved, and the service life of the tunnel structure is prolonged. And the settlement phenomenon of the open cut tunnel structure can be prevented and treated.

Description

Technical Field

[0001] This application relates to the field of road traffic safety technology, specifically to a high-fill open tunnel anti-settlement mechanism based on a pile-slab structure and its construction method. Background Technology

[0002] In high-fill open-cut tunnel projects, voids may occur between the bottom of the pile-slab structure and the foundation. This is caused by factors such as foundation settlement and uneven stress. Voids at the bottom of the slab alter the structural stress state, increase stress concentration, and ultimately lead to structural failure. Currently, monitoring and treatment technologies for voids at the bottom of the slab are not yet perfect. Furthermore, for existing voids, there are no effective treatment methods, typically requiring large-scale excavation and reinforcement measures, which are not only difficult and costly to implement but also severely impact the surrounding environment and traffic.

[0003] Isolation piles are widely used in tunnel engineering as an important means of reducing foundation settlement and protecting surrounding structures. Common types of isolation piles include steel pipe piles and micropiles, which play an important role in scenarios where existing structures are excavated adjacent to tunnels. However, existing isolation pile technology has significant limitations in addressing the specific problem of settlement prevention in open-cut tunnels with high backfill. Because the geological conditions and loads in the high backfill area of ​​an open-cut tunnel differ significantly from those in the case of tunnel excavation adjacent to existing structures, existing isolation piles cannot effectively reduce the impact of the additional stress generated by the high backfill load on the tunnel structure. This leads to settlement during tunnel operation, seriously affecting the tunnel's safety and service life. Summary of the Invention

[0004] This application provides a high-fill open-cut tunnel anti-settlement mechanism and its construction method based on a pile-slab structure, which can solve the problem of difficulty in preventing and dealing with the possible settlement of the open-cut tunnel structure in the prior art.

[0005] In a first aspect, embodiments of this application provide a high-fill open-cut tunnel anti-settlement mechanism based on a pile-slab structure, comprising: The tunnel structure has a first grouting pipe buried on its outer side and at its bottom; a second grouting pipe connected to the first grouting pipe is installed in the internal space of the tunnel structure; the first grouting pipe has a grout outlet, and the second grouting pipe has a grouting outlet. The gravel isolation zone is distributed on both sides of the transverse direction of the tunnel structure and is spaced apart from the tunnel structure.

[0006] In some embodiments, in the vertical direction, the bottom of the gravel isolation strip is located below the bottom of the tunnel structure, and the top of the gravel isolation strip is located above the top of the tunnel structure.

[0007] In some embodiments, the gravel constituting the gravel buffer zone has a circular or elliptical cross-section.

[0008] In some embodiments, multiple first grouting pipes are provided, and the length direction of each first grouting pipe is perpendicular to the axial direction of the open-cut tunnel structure. In both the vertical direction and the axial direction of the open-cut tunnel structure, multiple first grouting pipes are arranged at equal intervals.

[0009] In some embodiments, the first grouting pipe and the second grouting pipe are perforated corrugated pipes.

[0010] In some embodiments, a grout stopper is also included, which is disposed at the grouting port of the second grouting pipe.

[0011] In some embodiments, the pile-slab structure of the open-cut tunnel structure includes a first base plate arranged transversely along the open-cut tunnel structure, and two second base plates arranged on both sides of the first base plate, wherein the second base plates are arranged at an obtuse angle to the first base plate.

[0012] In some embodiments, bored piles are also included, which are disposed at the bottom of the pile-slab structure to support the pile-slab structure and connect to the original strata.

[0013] Secondly, this application also provides a method for preventing settlement of high-fill open-cut tunnels based on pile-slab structures, implemented using the aforementioned anti-settlement mechanism for high-fill open-cut tunnels based on pile-slab structures, including the following steps: Remove the shallow overburden at the top of the open-cut tunnel and arrange bored piles along the structural axis of the open-cut tunnel. Backfill the fill material and pre-embed grouting pipes in the fill material layer. After backfilling to the bottom of the pile slab structure of the open tunnel structure, construct the main body of the open tunnel structure. Backfill the soil around the open tunnel and simultaneously construct gravel isolation strips on both sides of the open tunnel structure.

[0014] In some embodiments, after the bottom of the pile plate structure is found to be voided during later monitoring, the grout stop plug is opened for grouting, and the grouting port is sealed after the grouting is completed.

[0015] The beneficial effects of the technical solutions provided in this application include: This application provides a high-fill open-cut tunnel anti-settlement mechanism and its construction method based on a pile-slab structure. The anti-settlement mechanism includes: The tunnel structure has a first grouting pipe buried on its outer side and at its bottom; a second grouting pipe connected to the first grouting pipe is installed in the internal space of the tunnel structure; the first grouting pipe has a grout outlet, and the second grouting pipe has a grouting outlet. The gravel isolation zone is distributed on both sides of the transverse direction of the tunnel structure and is spaced apart from the tunnel structure.

[0016] Gravel isolation zones are distributed on both sides of the open-cut tunnel structure and spaced apart from it. This arrangement alters the stress transmission path caused by high backfill loads. Gravel has good permeability and some compressibility. Under high backfill loads, the gravel isolation zones can transfer shear stress through rotation, reducing the additional stress on the tunnel structure caused by lateral soil loads and lowering the possibility of settlement due to excessive additional stress. Furthermore, the gravel isolation zones can regulate uneven foundation settlement to some extent. Due to the complex geological conditions in the high-backfill area of ​​the open-cut tunnel, foundation settlement may vary at different locations. The presence of gravel isolation zones can balance this uneven settlement, making the settlement effect on the tunnel structure more uniform, avoiding structural stress concentration and damage caused by uneven settlement, and further preventing tunnel structure settlement problems.

[0017] A first grouting pipe is buried on the outer side of the bottom of the tunnel structure, and a second grouting pipe connected to it is installed inside the tunnel structure. The first grouting pipe has an outlet, and the second grouting pipe has an injection port. This design allows grout to be injected into the first grouting pipe through the injection port of the second grouting pipe when a void is found at the bottom of the slab or when the tunnel structure shows signs of settlement. The grout then flows out from the outlet to fill the void at the bottom of the slab. Compared with traditional large-scale excavation and reinforcement methods, this technical solution can achieve real-time and precise grouting treatment, with less construction difficulty, lower cost, and less impact on the surrounding environment and traffic.

[0018] In actual construction, grouting through a grouting pipe system ensures that the grout evenly fills the voids at the bottom of the slab, improving the treatment effect. Furthermore, because the grouting pipes are pre-installed, grouting can be carried out quickly when needed, eliminating the need for complex preparations and greatly improving efficiency. This also helps to promptly prevent further settlement of the tunnel structure.

[0019] The combined effect of gravel isolation strips and grouting pipe systems can improve the stress state of open-cut tunnel structures. Gravel isolation strips reduce the impact of additional stress on the tunnel structure, while the grouting pipe system promptly addresses the issue of voids at the bottom of the slab, preventing stress concentration in the structure. This results in a more stable stress state for the tunnel structure during operation, improving the overall stability and load-bearing capacity of the structure, and preventing and addressing settlement phenomena in open-cut tunnel structures. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is an overall schematic diagram of the construction of the anti-settlement mechanism provided in the embodiments of this application.

[0022] In the picture: 1. Open-cut tunnel structure; 2. Gravel isolation zone; 4. Drilled piles; 11. Pile-slab structure; 31. First grouting pipe; 32. Second grouting pipe. Detailed Implementation

[0023] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0024] This application provides a high-fill open-cut tunnel anti-settlement mechanism and its construction method based on a pile-slab structure, which can solve the problem of difficulty in preventing and dealing with the possible settlement of the open-cut tunnel structure in the prior art.

[0025] See Figure 1 As shown, in a first aspect, embodiments of this application provide a high-fill open-cut tunnel anti-settlement mechanism based on a pile-slab structure, comprising: The Mingdong Tunnel Structure 1 has a first grouting pipe 31 buried on its outer side and at its bottom; a second grouting pipe 32 connected to the first grouting pipe 31 is provided in the internal space of the Mingdong Tunnel Structure 1; the first grouting pipe 31 has a grout outlet and the second grouting pipe 32 has a grouting port. Gravel isolation zone 2 is distributed on both sides of the transverse direction of the tunnel structure 1 and is set at intervals with the tunnel structure 1.

[0026] Gravel isolation zones 2 are distributed on both sides of the open-cut tunnel structure 1 and spaced apart from it. This arrangement can alter the stress transmission path caused by high backfill loads. Gravel has good permeability and a certain degree of compressibility. Under high backfill loads, gravel isolation zones 2 can transfer shear stress through rotation, reducing the additional stress on the tunnel structure caused by lateral soil loads and decreasing the possibility of settlement due to excessive additional stress. Furthermore, gravel isolation zones 2 can regulate uneven settlement of the foundation to a certain extent. Due to the complex geological conditions in the high backfill area of ​​the open-cut tunnel, foundation settlement may vary at different locations. The presence of gravel isolation zones 2 can balance this uneven settlement, making the settlement effect on the tunnel structure more uniform, avoiding structural stress concentration and damage caused by uneven settlement, and further preventing settlement problems in the tunnel structure.

[0027] A first grouting pipe 31 is buried on the outer side of the bottom of the tunnel structure 1, and a second grouting pipe 32 connected to it is installed inside the tunnel structure 1. The first grouting pipe 31 has an outlet, and the second grouting pipe 32 has an injection port. This design allows grout to be injected into the first grouting pipe 31 through the injection port of the second grouting pipe 32 when a void is found at the bottom of the slab or when the tunnel structure shows signs of settlement. The grout then flows out from the outlet to fill the void area at the bottom of the slab. Compared with traditional large-scale excavation and reinforcement methods, this technical solution can achieve real-time and precise grouting treatment, with less construction difficulty, lower cost, and less impact on the surrounding environment and traffic.

[0028] In actual construction, grouting through a grouting pipe system ensures that the grout evenly fills the voids at the bottom of the slab, improving the treatment effect. Furthermore, because the grouting pipes are pre-installed, grouting can be carried out quickly when needed, eliminating the need for complex preparations and greatly improving efficiency. This also helps to promptly prevent further settlement of the tunnel structure.

[0029] The combined effect of the gravel isolation zone 2 and the grouting pipe system can improve the stress state of the open-cut tunnel structure 1. The gravel isolation zone 2 reduces the impact of additional stress on the tunnel structure, and the grouting pipe system promptly addresses the issue of voids at the bottom of the slab, avoiding stress concentration in the structure. This ensures that the tunnel structure is in a more stable stress state during operation, improving the overall stability and load-bearing capacity of the structure, and preventing and addressing settlement phenomena in the open-cut tunnel structure 1.

[0030] In some alternative embodiments, such as Figure 1As shown, in the vertical direction, the bottom of the gravel isolation zone 2 is below the bottom of the tunnel structure 1, and the top of the gravel isolation zone 2 is above the top of the tunnel structure 1. The gravel isolation zone 2 covers both the top and bottom of the tunnel structure 1 in the vertical direction, effectively blocking the transmission of additional stress generated by the high backfill load to the tunnel structure. This allows the gravel isolation zone 2 to form a continuous stress buffer layer, effectively dispersing and weakening stress from any direction (such as stress generated by the upper load or uneven settlement of the foundation below), thus more comprehensively protecting the tunnel structure from excessive stress and reducing the risk of settlement. The height of the gravel isolation zone 2 exceeds that of the tunnel structure, increasing the contact area with the surrounding soil. During stress transmission, a larger contact area means that stress can be dispersed over a wider range.

[0031] In some alternative embodiments, the gravel constituting the gravel isolation zone 2 has a circular or elliptical cross-section.

[0032] The regular shape and smooth, edgeless surface of the gravel in the gravel isolation zone 2 give it good rotational ability. When facing the side soil load, the gravel isolation zone 2 can effectively transfer shear stress through the rotation of the gravel, thereby significantly reducing the additional stress generated by the load on the tunnel structure and significantly reducing the risk of settlement of the tunnel structure due to stress exceeding the limit.

[0033] In practice, after the presence of gravel isolation zones, the deformation within the two isolation zones is significantly reduced, while the deformation within the isolation zone area is significantly increased. Through the "energy dissipation" of the isolation zones, the additional stress transmitted to the main body of the open-cut tunnel structure 1 can be effectively reduced, thereby reducing settlement.

[0034] In some alternative embodiments, multiple first grouting pipes 31 are provided, and the length direction of each first grouting pipe 31 is perpendicular to the axial direction of the open tunnel structure 1. In the vertical direction and the axial direction of the open tunnel structure 1, multiple first grouting pipes 31 are arranged at equal intervals.

[0035] Multiple first grouting pipes 31 are installed, with the length direction of each first grouting pipe 31 perpendicular to the axis of the open-cut tunnel structure 1, and they are arranged at equal intervals in both the vertical direction and the axis of the open-cut tunnel structure 1. This layout allows the grouting pipes to cover a wider area of ​​the bottom and surrounding area of ​​the open-cut tunnel structure 1, forming a comprehensive grouting network. During grouting, the grout can be injected evenly into the foundation from multiple directions and locations, effectively filling the voids at the bottom of the slab and the pores and cracks in the foundation, avoiding grouting blind spots, thereby improving the uniformity and integrity of grouting, enhancing the density and bearing capacity of the foundation, and better preventing and treating settlement problems of the tunnel structure.

[0036] Multiple equidistant first grouting pipes 31 can be used to precisely control the grouting range by controlling the grouting volume and pressure of different grouting pipes, according to actual needs. For example, when local voids are found at the bottom of the slab or when the foundation settlement is large, grouting can be carried out on the first grouting pipes 31 at the corresponding locations, improving the targeting and effectiveness of grouting and avoiding waste of grout and excessive diffusion that may have an adverse impact on the surrounding environment.

[0037] In some optional embodiments, the first grouting pipe 31 and the second grouting pipe 32 are perforated corrugated pipes. These perforated corrugated pipes possess a certain degree of flexibility and deformation capacity. When the tunnel structure 1 is subjected to load and deforms, the perforated corrugated pipes can deform accordingly without easily breaking, ensuring the long-term stability and reliability of the grouting system. Furthermore, the corrugated structure of the perforated corrugated pipes increases the friction with the surrounding soil, facilitating thorough mixing and bonding of the grout with the soil. This allows the grouted foundation and tunnel structure to work together more effectively and share the load. The perforated corrugated pipes are lightweight, easy to transport and install, and can be laid mechanically or manually, reducing construction difficulty and labor intensity. As a common pipe material, the perforated corrugated pipe is relatively inexpensive, and its good durability and reliability ensure long-term good grouting performance, reducing maintenance and replacement costs due to grouting system damage and contributing to cost savings in construction.

[0038] In some alternative embodiments, a grout stopper is also included, which is disposed at the grouting port of the second grouting pipe 32. The grout stopper disposed at the grouting port of the second grouting pipe 32 can effectively prevent backflow and leakage of grout during the grouting process, avoiding harm and pollution to construction personnel and the surrounding environment.

[0039] In some alternative embodiments, such as Figure 1 As shown, the pile-slab structure 11 of the tunnel structure 1 includes a first bottom plate arranged transversely along the tunnel structure 1, and two second bottom plates arranged on both sides of the first bottom plate, with the second bottom plates arranged at an obtuse angle to the first bottom plate.

[0040] The first base plate is positioned laterally, with two second base plates positioned on either side of the first base plate at obtuse angles. This structural form allows for a more rational distribution of the superstructure load during transmission. This design avoids excessive force concentration, reduces the risk of structural failure due to excessive local stress, and improves the structure's load-bearing capacity. When subjected to external forces, the plates constrain each other, collectively resisting deformation, thereby enhancing the overall structural rigidity. Furthermore, this zigzag-like design offers certain economic advantages while ensuring structural performance. The rational design of the pile-slab structure 11 fully utilizes the strength of the materials, reduces material waste, and lowers structural costs.

[0041] In some alternative embodiments, such as Figure 1 As shown, it also includes bored piles 4, which are installed at the bottom of the pile-slab structure 11 to support the pile-slab structure 11 and connect it to the original stratum. This combined design of the pile-slab structure 11 and the bored piles 4 is beneficial to improving the load-bearing capacity of the structure. The layout of the first and second base plates makes the center of gravity distribution of the structure more reasonable, while the bored piles 4 penetrate deep into the stratum, providing strong pull-out resistance. When the structure is subjected to overturning moment, the bored piles 4 can effectively resist the upward pull-out tendency of the structure, ensure the stability of the structure, and prevent the overturning accident of the open-cut tunnel structure 1. When local foundation settlement occurs, the pile-slab structure 11 can coordinate uneven settlement through its own deformation, while the bored piles 4 can limit the excessive settlement and tilting of the structure, ensure the overall flatness and stability of the open-cut tunnel structure 1, and reduce the damage to the structure caused by uneven settlement.

[0042] Secondly, this application also provides a method for preventing settlement of high-fill open-cut tunnels based on pile-slab structures, implemented using the aforementioned anti-settlement mechanism for high-fill open-cut tunnels based on pile-slab structures, including the following steps: Remove the shallow overburden at the top of the open tunnel and arrange bored piles 4 along the axis of the open tunnel structure 1. Backfill the fill material and pre-embed the first grouting pipe 31 in the fill material layer. After backfilling to the bottom of the pile slab structure 11 of the open tunnel structure 1, construct the main body of the open tunnel structure 1. Backfill the soil around the open tunnel, and simultaneously construct gravel isolation strips 2 on both sides of the open tunnel structure 1.

[0043] During actual construction, when removing the shallow overburden at the top of the tunnel opening, a 50cm layer of shallow overburden can be removed, and bored piles 4 can be installed. AB group filling materials are then used. After backfilling to the bottom of the pile-slab structure 11, construction of the tunnel opening structure 1 can begin. Finally, backfilling of the soil around the tunnel opening structure is carried out, with layered backfilling and compaction. Small machinery is used to compact the soil 1m on both sides of the structure. Large machinery is used after backfilling to the top 5m of the tunnel opening structure 1. While backfilling the soil, a gravel isolation strip 2 is also backfilled. The gravel isolation strip 2 is 1m wide and uses gravel with a circular or elliptical cross-section. The depth should penetrate the underconsolidated layer (to eliminate negative skin friction effect).

[0044] In the vertical direction, the first grouting pipe 31 is located 0.5m below the lowest point of the pile-slab structure 11, and each subsequent pipe is spaced 0.5m apart until the original stratum. At the same time, the first grouting pipe 31 is connected to each other to the tunnel interior for later grouting, and the grouting port is sealed with a grout stop plug.

[0045] In some alternative embodiments, after the bottom of the pile plate structure 11 is detected to be voided, the grout stop plug is opened for grouting, and the grouting port is sealed after the grouting is completed.

[0046] In the description of this application, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application 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 this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0047] It should be noted that in this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0048] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A settlement prevention mechanism for high-fill open-cut tunnels based on pile-slab structures, characterized in that, include: The Mingdong Tunnel Structure (1) has a first grouting pipe (31) buried on its outer side and at its bottom; a second grouting pipe (32) connected to the first grouting pipe (31) is provided in the internal space of the Mingdong Tunnel Structure (1); the first grouting pipe (31) has a grout outlet and the second grouting pipe (32) has a grouting port. Gravel isolation strips (2) are distributed on both sides of the transverse direction of the Mingdong tunnel structure (1) and are spaced apart from the Mingdong tunnel structure (1).

2. The anti-settlement mechanism for high-fill open-cut tunnels based on pile-slab structure as described in claim 1, characterized in that: In the vertical direction, the bottom of the gravel isolation strip (2) is located below the bottom of the tunnel structure (1), and the top of the gravel isolation strip (2) is located above the top of the tunnel structure (1).

3. The anti-settlement mechanism for high-fill open-cut tunnels based on pile-slab structure as described in claim 1, characterized in that: The gravel that makes up the gravel isolation zone (2) has a circular or elliptical cross section.

4. The anti-settlement mechanism for high-fill open-cut tunnels based on pile-slab structure as described in claim 1, characterized in that: Multiple first grouting pipes (31) are provided. The length direction of each first grouting pipe (31) is perpendicular to the axis direction of the open tunnel structure (1), and multiple first grouting pipes (31) are arranged at equal intervals in the vertical direction and the axis direction of the open tunnel structure (1).

5. The anti-settlement mechanism for high-fill open-cut tunnels based on pile-slab structure as described in claim 1 or 4, characterized in that: The first grouting pipe (31) and the second grouting pipe (32) are perforated corrugated pipes.

6. The anti-settlement mechanism for high-fill open-cut tunnels based on pile-slab structure as described in claim 1, characterized in that: It also includes a grout stopper, which is installed at the grouting port of the second grouting pipe (32).

7. The anti-settlement mechanism for high-fill open-cut tunnels based on pile-slab structure as described in claim 1, characterized in that: The pile-slab structure (11) of the open tunnel structure (1) includes a first bottom plate arranged transversely along the open tunnel structure (1) and two second bottom plates arranged on both sides of the first bottom plate, wherein the second bottom plates are arranged at an obtuse angle to the first bottom plate.

8. The anti-settlement mechanism for high-fill open-cut tunnels based on pile-slab structure as described in claim 7, characterized in that: It also includes bored piles (4), which are set at the bottom of the pile-slab structure (11) to support the pile-slab structure (11) and connect with the original stratum.

9. A method for preventing settlement of high-fill open-cut tunnels based on pile-slab structures, characterized in that, The implementation using the anti-settlement mechanism for high-fill open-cut tunnels based on pile-slab structures as described in claims 1-8 includes the following steps: Remove the shallow overburden at the top of the tunnel opening and arrange bored piles (4) along the axis of the tunnel structure (1). Backfill the fill material and pre-embed the first grouting pipe (31) in the fill material layer. After backfilling to the bottom of the pile plate structure (11) of the open tunnel structure (1), construct the main body of the open tunnel structure (1). Backfill the soil around the open tunnel and simultaneously construct gravel isolation strips (2) on both sides of the open tunnel structure (1).

10. The method for preventing settlement of high-fill open-cut tunnels based on pile-slab structures as described in claim 9, characterized in that: After monitoring revealed that the bottom of the pile plate structure (11) was detached, the grout stop plug was opened for grouting. After the grouting was completed, the grouting port was sealed.

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