Drainage tunnel structure

Abstract

The utility model relates to tunnel construction technical field provides a kind of waterproof and drainage tunnel open cut structure, comprising: open cut lining;Slope, at least one side of the open cut lining outside is set;Backfill layer, filled in the space surrounded by the open cut lining and the slope;Water-resisting layer, laid above the backfill layer;The water-resisting layer includes first waterproof layer, bearing layer and planting soil layer sequentially laid from bottom to top, and the planting soil layer is suitable for planting vegetation.Such setting, compared with the related art, the above water-resisting layer reduces the dependence on clay, thereby reducing the difficulty and cost of material procurement, improve economy, and planting soil layer can provide suitable growth environment for vegetation and soil microbial community, maximally reduce the influence of engineering on ecological environment.

Description

Technical Field

[0001] This utility model relates to the field of tunnel construction technology, and in particular to a drainage tunnel open-cut structure. Background Technology

[0002] Open-cut tunnels are a special structural form in tunnel engineering, mainly used in tunnel entrance / exit sections or cutting sections to cope with complex terrain and geological conditions or situations with safety hazards such as collapses, rockfalls, and landslides. Their structural form is usually arched or canopy-type, using reinforced concrete or masonry as lining materials, and the top needs to be backfilled with soil and rock to buffer external loads.

[0003] The tunnel not only serves the function of structural stability, but also needs a complete waterproofing and drainage system to ensure structural durability and avoid problems such as cracking and leakage caused by water erosion. After the tunnel lining is buried by backfill soil and rocks, a waterproof layer needs to be laid on top to form a water barrier to protect the tunnel lining from water seepage erosion. In related technologies, the waterproof layer is generally made of clay. The low permeability of clay can effectively prevent or significantly slow down the vertical infiltration of rainwater.

[0004] However, due to various factors such as construction environment, geological characteristics and distribution limitations, mining technology, transportation and storage costs, there are problems such as difficulty in obtaining clay materials, high material costs, and poor economic efficiency. In addition, due to the low air and water permeability of clay, it can damage vegetation and soil microbial communities, and have a significant impact on the ecological environment.

[0005] Therefore, how to reduce reliance on clay, thereby lowering material costs, improving economic efficiency, and minimizing the impact of projects on the ecological environment has become an important issue that urgently needs to be addressed. Utility Model Content

[0006] This utility model provides a drainage tunnel open-cut structure to solve the problems of difficulty in obtaining waterproof layer materials, high cost, poor economic efficiency and significant environmental impact in the prior art. It can reduce the dependence on clay, thereby reducing material costs, improving economic efficiency and minimizing the impact of the project on the ecological environment.

[0007] This utility model provides a drainage tunnel open-cut structure, including:

[0008] The lining of the tunnel;

[0009] A ramp is provided on at least one side outside the lining of the tunnel;

[0010] The backfill layer fills the space enclosed by the tunnel lining and the slope.

[0011] A waterproof layer is laid on top of the backfill layer; the waterproof layer includes a first waterproof layer, a bearing layer and a planting soil layer laid sequentially from bottom to top, and the planting soil layer is suitable for planting vegetation.

[0012] According to the present invention, a waterproof tunnel structure is provided, wherein the first waterproof layer includes a waterproof membrane.

[0013] According to the present invention, a drainage tunnel open-cut structure is provided, wherein the bearing layer includes: a sand and gravel layer and an adhesive layer filling the upper surface of the sand and gravel layer.

[0014] According to the present invention, a drainage tunnel open-cut structure is provided, wherein a first leveling layer is laid between the first waterproof layer and the backfill layer; and / or, a first protective layer is laid between the first waterproof layer and the bearing layer.

[0015] According to the present invention, a drainage tunnel open-cut structure is provided, wherein the upper surface of the waterproof layer is provided with a water collection trough extending along the axial direction of the open-cut lining;

[0016] The upper surface of the waterproof layer is set as an inclined surface and forms a lower side at the water collection trough.

[0017] According to the present invention, a drainage tunnel open-cut structure is provided in which the bottom of the slope gradually approaches the open-cut lining, so that the outer periphery of the open-cut lining and the bottom of the slope form a water passage trough along the axial direction of the open-cut lining.

[0018] It also includes a blind pipe structure; the water inlet of the blind pipe structure is connected to the water passage trough, and the water outlet is connected to the drainage ditch inside the open tunnel lining.

[0019] According to the present invention, a drainage tunnel open-cut structure is provided, wherein the water passage is filled with a reverse filter layer, and the water inlet end of the blind pipe structure is located below or inside the reverse filter layer.

[0020] According to the present invention, a drainage tunnel open-cut structure is provided, wherein the blind pipe structure includes:

[0021] Longitudinal blind pipes are arranged along the length of the water passage trough;

[0022] Multiple vertical blind pipes are arranged along the length of the longitudinal blind pipe; one end of the vertical blind pipe is connected to the longitudinal blind pipe, and the other end is connected to the drainage ditch.

[0023] According to the present invention, a drainage tunnel open-cut structure is provided, wherein a second waterproof layer is laid on the outer periphery of the open-cut lining.

[0024] The second waterproof layer comprises a waterproof membrane and a geotextile nonwoven fabric layer laid in sequence.

[0025] According to the present invention, a drainage tunnel open-cut structure is provided, wherein a second leveling layer is provided between the second waterproof layer and the open-cut lining; and / or, a second protective layer is provided between the second waterproof layer and the backfill layer.

[0026] According to the present invention, a drainage tunnel open-cut structure is provided, wherein the vertical blind pipe and the longitudinal blind pipe are connected by a tee joint.

[0027] The drainage tunnel structure provided by this utility model features a first waterproof layer that forms a continuous waterproof barrier outside the backfill layer, preventing water seepage into the backfill layer and eroding the tunnel lining. The supporting layer provides a stable foundation for the planting soil layer and subsequent vegetation, preventing the planting soil from being washed away by water or slipping due to instability of the underlying soil layer, ensuring the thickness and integrity of the planting soil layer and providing ample space for plant root growth and development. The planting soil possesses good water retention, permeability, and abundant nutrients, providing a suitable growth environment for vegetation. After planting, the roots and fallen leaves form a natural covering layer, reducing rainwater infiltration and erosion of the waterproof layer surface, ensuring its waterproofing effect. Compared to related technologies, this waterproof layer reduces reliance on clay, thereby lowering material sourcing difficulties and costs, improving economic efficiency. Furthermore, the planting soil layer provides a suitable growth environment for vegetation and soil microbial communities, minimizing the project's impact on the ecological environment. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of the drainage tunnel structure provided in this embodiment of the utility model.

[0030] Figure 2 This is a schematic diagram of the structure of the waterproof layer provided in this embodiment of the utility model.

[0031] Figure 3 yes Figure 1 A magnified view of part A in the middle.

[0032] Figure 4 This is a schematic diagram of the blind tube structure provided in this embodiment of the utility model.

[0033] Figure label:

[0034] 10. Open-cut lining; 20. Slope; 30. Backfill layer; 40. Waterproof layer; 41. First waterproof layer; 42. Bearing layer; 420. Sand and gravel layer; 421. Bonding layer; 43. Planting soil layer; 44. First leveling layer; 45. First protective layer; 46. Water collection trough; 50. Water passage trough; 51. Filter layer; 60. Blind pipe structure; 61. Longitudinal blind pipe; 62. Vertical blind pipe; 70. Second waterproof layer; 71. Second leveling layer; 72. Second protective layer. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0036] To better understand the drainage tunnel open-cut structure provided in this utility model embodiment, its application background is first introduced. As a special structural form in tunnel engineering, the external structural surface of the tunnel lining needs to be buried with backfill soil and rocks. At the same time, in order to avoid rainwater erosion, after the open-cut lining is buried with backfill soil and rocks, a waterproof layer needs to be laid on the top to form a water barrier to protect the open-cut lining from water seepage erosion. In related technologies, the waterproof layer is generally made of clay. The low permeability of clay can effectively prevent or significantly slow down the vertical infiltration of rainwater.

[0037] However, due to various factors such as construction environment, geological characteristics and distribution limitations, mining technology, transportation and storage costs, there are problems such as difficulty in obtaining clay materials, high material costs, and poor economic efficiency. In addition, due to the low air and water permeability of clay, it can damage vegetation and soil microbial communities, and have a significant impact on the ecological environment.

[0038] Therefore, how to reduce reliance on clay, thereby reducing the difficulty and cost of sourcing materials, improving economic efficiency, and minimizing the impact of projects on the ecological environment has become an important issue that urgently needs to be addressed.

[0039] Against the above background, this utility model embodiment provides a drainage tunnel open-cut structure that can reduce dependence on clay, thereby reducing material costs, improving economic efficiency, and minimizing the impact of the project on the ecological environment.

[0040] The following is combined Figures 1-4 This invention describes the open-cut structure of a drainage tunnel.

[0041] Reference Figure 1 and Figure 2 A drainage tunnel open-cut structure includes an open-cut lining 10, a slope 20, a backfill layer 30, and a waterproof layer 40; wherein, the slope 20 is located on at least one side outside the open-cut lining 10; the backfill layer 30 fills the space enclosed by the open-cut lining 10 and the slope 20, and is used to cover the external structural surface of the open-cut lining 10; the waterproof layer 40 is laid on top of the backfill layer 30, and the waterproof layer 40 includes a first waterproof layer 41, a bearing layer 42, and a planting soil layer 43 laid sequentially from bottom to top, and the planting soil layer 43 is suitable for planting vegetation.

[0042] In actual construction, after the outer structural surface of the tunnel lining 10 is buried by the backfill layer 30, the waterproof layer 40 is laid on top of the backfill layer 30. The first waterproof layer 41 can form a continuous waterproof barrier outside the backfill layer 30, preventing water from seeping into the backfill layer 30 and causing erosion to the tunnel lining 10. The bearing layer 42 can provide a stable support base for the planting soil layer 43 and subsequent vegetation, making the planting soil less likely to be washed away by water flow or slip due to the instability of the underlying soil layer, ensuring the thickness and integrity of the planting soil layer 43, and providing sufficient space for the growth and development of plant roots. The planting soil has good water retention, air permeability and rich nutrients, which can provide a suitable growth environment for vegetation. After the vegetation is planted, its roots and fallen leaves can form a natural covering layer on top, which can reduce rainwater infiltration and erosion of the surface of the waterproof layer 40, ensuring the waterproof effect of the waterproof layer 40.

[0043] Compared to related technologies, the aforementioned waterproof layer 40 reduces the reliance on clay, thereby reducing the difficulty and cost of material sourcing and improving economic efficiency. Furthermore, the planting soil layer 43 can provide a suitable growth environment for vegetation and soil microbial communities, minimizing the impact of the project on the ecological environment.

[0044] It should be noted that, depending on the specific structural form of the tunnel opening, the ramp 20 can be set on one or both sides outside the tunnel lining 10. For example, in a road cut type opening, the ramp 20 is set on both sides outside the tunnel lining 10, while in a single-pressure type opening, the ramp 20 is set on one side outside the tunnel lining 10. The specific arrangement can be flexibly adjusted according to the actual construction scenario. Since the different specific structural forms of the tunnel opening do not affect the structure and arrangement of the waterproof layer 40, the specific structural form of the tunnel opening is not limited in this embodiment of the utility model.

[0045] In one embodiment of this utility model, the tunnel lining 10 is an arched structure, which can be formed using construction methods such as formwork. The bottom of the slope 20 gradually approaches the tunnel lining 10 and encloses it to form a backfill space. Backfill layer 30 is formed by ramming soil and rocks into the backfill space, and the entire tunnel lining 10 is buried in the backfill layer 30, which buffers external loads. A waterproof layer 40 is laid on the upper surface of the backfill layer 30 to prevent rainwater infiltration.

[0046] As described above, the backfill layer 30 includes a first waterproof layer 41, a bearing layer 42, and a planting soil layer 43 laid sequentially from bottom to top.

[0047] In one embodiment of this utility model, the first waterproof layer 41 is made of a waterproof board, which can be made of materials such as high-density polyethylene (HDPE) and polyvinyl chloride (PVC). It has excellent impermeability and prevents water from penetrating into the backfill layer 30.

[0048] In one embodiment of this utility model, a first leveling layer 44 is provided between the first waterproof layer 41 and the backfill layer 30. This arrangement improves the surface smoothness of the backfill layer 30, allowing the first waterproof layer 41 to be laid more smoothly on the backfill layer 30. Simultaneously, the first leveling layer 44 effectively eliminates sharp edges on the surface of the backfill layer 30, thus providing protection for the first waterproof layer 41, preventing it from being punctured by sharp edges, and ensuring the waterproof effect of the first waterproof layer 41.

[0049] Specifically, the first leveling layer 44 is a 15cm thick C15 concrete leveling layer.

[0050] In one embodiment of this utility model, a first protective layer 45 is laid between the first waterproof layer 41 and the supporting layer 42. This arrangement separates the first waterproof layer 41 and the supporting layer 42 through the first protective layer 45, preventing the pressure of the supporting layer 42 from directly acting on the first waterproof layer 41, reducing the risk of damage to the first waterproof layer 41 due to external forces, and improving the structural integrity and durability of the first waterproof layer 41.

[0051] Specifically, the first protective layer 45 is a 3cm thick M10 cement mortar protective layer.

[0052] In one embodiment of this utility model, the bearing layer 42 serves as the supporting base for the planting soil layer 43 and subsequent vegetation. Specifically, it includes a sand and gravel layer 420 and an adhesive layer 421 filled on the upper surface of the sand and gravel layer 420. The sand and gravel layer 420 is 25cm thick and consists of sand and pebbles. The sand and pebbles have virtually no sharp edges, which can reduce damage to the underlying structure. Furthermore, the porous structure of the sand and pebbles can quickly drain infiltrated rainwater. The adhesive layer 421 is made of cement mortar. The adhesive layer 421 can bind the originally loose pebbles and sand on the surface of the sand and gravel layer 420 together to form a relatively stable base structure. At the same time, it can block the infiltration channels of water to a certain extent, ensuring the moisture of the planting soil layer 43 and preventing the loss of planting soil.

[0053] The source, form, and thickness of the planting soil can be selected according to the actual construction scenario. For example, it can be natural soil from the construction site, or it can be arable soil or prepared soil. No specific restrictions are made in this embodiment of the utility model.

[0054] In one embodiment of this utility model, a water collection trough 46 extending axially along the tunnel lining 10 is provided on the upper surface of the waterproof layer 40. The upper surface of the waterproof layer 40 is set as an inclined surface and forms a lower side at the water collection trough 46. With this configuration, when there is heavy rainfall, the rainwater can flow into the water collection trough 46 under the action of gravity and be discharged from the water collection trough 46, reducing the burden on the waterproof layer 40 and further reducing the risk of rainwater seepage downwards.

[0055] In order to promptly drain water that has seeped into the backfill layer 30 and ensure that the tunnel lining 10 is protected from water erosion, in one embodiment of this utility model, referring to... Figure 3 and Figure 4 The bottom of the slope 20 gradually approaches the tunnel lining 10, forming a water-passing channel 50 along the axial direction of the tunnel lining 10 with the bottom of the slope 20. The tunnel structure also includes a blind pipe structure 60, with its inlet end connected to the water-passing channel 50 and its outlet end connected to the drainage ditch inside the tunnel lining 10. With this configuration, seepage water will flow downwards along the slope 20 under gravity and eventually collect in the water-passing channel 50. Because the inlet end of the blind pipe structure 60 is connected to the water-passing channel 50, the seepage water flowing into the water-passing channel 50 can be quickly and efficiently discharged through the blind pipe structure 60, effectively reducing the erosion of the tunnel lining 10 by seepage water.

[0056] In one embodiment of this utility model, the water passage 50 is filled with a filter layer 51, and the water inlet end of the blind pipe structure 60 is located below or inside the filter layer 51. With this configuration, the filter layer 51 can provide protection for the blind pipe after backfilling with soil and rock, reducing the problem of debris such as gravel and silt clogging the blind pipe and ensuring smooth drainage. Furthermore, the filter layer 51 can also filter out silt and impurities mixed in the seepage water, effectively reducing the problem of fine-particle silt accumulation causing blockage of the drainage system. This allows for more timely and effective removal of seepage water from the outside of the open-cut lining 10, ensuring the structural stability of the tunnel.

[0057] Specifically, the filter layer 51 can be made of sand and pebbles.

[0058] In one embodiment of the present invention, the blind pipe structure 60 includes a longitudinal blind pipe 61 and a vertical blind pipe 62; wherein, the longitudinal blind pipe 61 is arranged along the tunnel axis and located inside or below the filter layer 51, forming the water inlet end of the blind pipe structure 60; multiple vertical blind pipes 62 are arranged along the length direction of the longitudinal blind pipe 61, one end of the vertical blind pipe 62 is connected to the longitudinal blind pipe 61, and the other end is connected to the drainage ditch.

[0059] With this configuration, the longitudinal blind pipe 61 arranged along the tunnel axis and the multiple vertical blind pipes 62 arranged along the length of the longitudinal blind pipe 61 enable the blind pipe structure 60 to fully collect the seepage water collected in the water tank 50 and quickly guide the seepage water into the drainage ditch, which helps to improve drainage efficiency.

[0060] In one embodiment of this utility model, the longitudinal blind pipe 61 and the vertical blind pipe 62 are connected by a tee connector. Specifically, the longitudinal blind pipe 61 is segmented, two of the interfaces of the tee connector are used to connect to two adjacent segments of the longitudinal blind pipe 61 respectively, and the other interface is used to connect to the vertical blind pipe 62.

[0061] In one embodiment of this utility model, the open-cut structure of the drainage tunnel further includes a second waterproof layer 70 laid on the outer periphery of the open-cut lining 10. The second waterproof layer 70 can form a continuous waterproof barrier on the outside of the open-cut lining 10, thereby further reducing the erosion of the open-cut lining 10 by seepage.

[0062] Specifically, the second waterproof layer 70 includes a waterproof membrane and a geotextile laid in sequence; wherein the waterproof membrane is laid around the outer periphery of the open tunnel lining 10, and the geotextile is laid around the outer periphery of the waterproof membrane to provide protection for the waterproof membrane.

[0063] In one embodiment of this utility model, a second leveling layer 71 is laid between the second waterproof layer 70 and the open-cut lining 10. The second leveling layer 71 can improve the surface flatness of the outer periphery of the open-cut lining 10, so that the waterproof membrane can be laid more smoothly on the outside of the open-cut lining 10. At the same time, the second leveling layer 71 can effectively eliminate the sharp edges and corners of the outer periphery of the open-cut lining 10, thereby providing protection for the waterproof membrane, preventing the waterproof membrane from being punctured by the edges and corners, and ensuring the waterproof effect of the second waterproof layer 70.

[0064] Specifically, the second leveling layer 71 is a 3cm thick M10 mortar leveling layer.

[0065] In one embodiment of this utility model, a second protective layer 72 is laid between the second waterproof layer 70 and the backfill layer 30. This arrangement separates the second waterproof layer 70 from the backfill layer 30, preventing the pressure of the backfill layer 30 from directly acting on the second waterproof layer 70, reducing the risk of damage to the second waterproof layer 70 due to external forces, and improving the structural integrity and durability of the second waterproof layer 70.

[0066] Specifically, the second protective layer 72 is a 6cm thick brick protective layer.

[0067] It should be further pointed out that the above description of the tunnel opening structure is only a brief overview, and its purpose is to provide a more intuitive understanding of the waterproofing and drainage structure provided by the present invention. Of course, in order to realize the function of the tunnel itself, the tunnel opening may also include other structures, such as sidewall backfill layers, corner backfill layers, etc., and the specific forms of sidewall backfill layers, corner backfill layers, etc. will vary depending on the tunnel type. The specific designs can be adapted to the actual construction scenario, and will not be listed in detail in the present invention.

[0068] It is understood that, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of the different embodiments or examples.

[0069] Through the drainage tunnel open-cut structure provided by this utility model embodiment, the first waterproof layer 41 can form a continuous waterproof barrier outside the backfill layer 30, preventing water seepage into the backfill layer 30 and causing erosion to the open-cut lining 10; the bearing layer 42 can provide a stable support base for the planting soil layer 43 and subsequent vegetation, making the planting soil less likely to be washed away by water flow or slip due to the instability of the lower soil layer, ensuring the thickness and integrity of the planting soil layer 43, and providing sufficient space for the growth and development of plant roots; the planting soil has good water retention, air permeability and rich nutrients, which can provide a suitable growth environment for vegetation. After the vegetation is planted, its roots and fallen leaves can form a natural covering layer on top, which can reduce the infiltration of rainwater and the scouring of the surface of the waterproof layer 40, ensuring the waterproof effect of the waterproof layer 40. Compared to related technologies, the aforementioned waterproof layer 40 reduces the reliance on clay, thereby reducing the difficulty and cost of material sourcing and improving economic efficiency. Furthermore, the planting soil layer 43 can provide a suitable growth environment for vegetation and soil microbial communities, minimizing the impact of the project on the ecological environment.

[0070] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A waterproofing and drainage tunnel structure, characterized by, include: The lining of the tunnel (10); A ramp (20) is provided on at least one side outside the tunnel lining (10); The backfill layer (30) fills the space enclosed by the tunnel lining (10) and the slope (20); A waterproof layer (40) is laid on top of the backfill layer (30); The waterproof layer (40) includes a first waterproof layer (41), a bearing layer (42), and a planting soil layer (43) laid sequentially from bottom to top. The planting soil layer (43) is suitable for planting vegetation.

2. The waterproofed tunnel structure according to claim 1, wherein The first waterproof layer (41) includes a waterproof membrane.

3. The waterproofed tunnel structure according to claim 1, wherein The bearing layer (42) includes: a sand and gravel layer (420) and an adhesive layer (421) filled on the upper surface of the sand and gravel layer (420).

4. The open-cut structure of the drainage tunnel according to claim 2, characterized in that, A first leveling layer (44) is laid between the first waterproof layer (41) and the backfill layer (30); and / or, a first protective layer (45) is laid between the first waterproof layer (41) and the bearing layer (42).

5. The drainage tunnel open-cut structure according to any one of claims 1 to 4, characterized in that, The upper surface of the waterproof layer (40) is provided with a water collection trough (46) extending along the axial direction of the tunnel lining (10); The upper surface of the waterproof layer (40) is set as an inclined surface and forms a lower side at the water collection tank (46).

6. The waterproofed tunnel structure according to claim 1, wherein The bottom of the slope (20) gradually approaches the tunnel lining (10), so that the outer periphery of the tunnel lining (10) and the bottom of the slope (20) form a water passage (50) along the axial direction of the tunnel lining (10). It also includes a blind pipe structure (60); the water inlet of the blind pipe structure (60) is connected to the water passage (50), and the water outlet is connected to the drainage ditch inside the open tunnel lining (10).

7. The waterproofed tunnel structure according to claim 6, wherein The water tank (50) is filled with a reverse filter layer (51), and the water inlet of the blind pipe structure (60) is located below or inside the reverse filter layer (51).

8. The waterproofed tunnel structure according to claim 6, wherein The blind tube structure (60) includes: A longitudinal blind pipe (61) is arranged along the length of the water passage (50); There are multiple vertical blind pipes (62) arranged along the length of the longitudinal blind pipe (61); one end of the vertical blind pipe (62) is connected to the longitudinal blind pipe (61), and the other end is connected to the drainage ditch.

9. The waterproofed tunnel structure according to claim 1, wherein The outer periphery of the tunnel lining (10) is covered with a second waterproof layer (70); The second waterproof layer (70) comprises a waterproof liner and a geotextile nonwoven fabric layer laid in sequence.

10. The waterproofed tunnel structure according to claim 9, wherein A second leveling layer (71) is provided between the second waterproof layer (70) and the open-cut lining (10); and / or, a second protective layer (72) is provided between the second waterproof layer (70) and the backfill layer (30).

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