A tunnel lining

Abstract

This utility model relates to the field of tunnel engineering, specifically to a tunnel lining. It includes: an upper tunnel; an outer layer of reinforcing steel bars, primarily arched, located on the upper outer side of the upper tunnel; an inner layer of reinforcing steel bars, also arched, located on the inner side of the upper tunnel, situated on one side of the outer layer; and a lower tunnel fixed to the lower part of the upper tunnel. A concrete lining layer for the upper tunnel is provided between the outer and inner layers of reinforcing steel bars. Furthermore, a wedge-shaped pad is provided between the upper and lower tunnels. This wedge-shaped pad is a concrete structure, with its inward-facing height greater than its outward-facing height, and is located within a wedge space. Through the structural design of the upper and lower tunnels working together, the safety and stability requirements of the tunnel are met. Furthermore, the design of the wedge-shaped pad and the wedge space ensures that the concrete sidewalls of the upper and lower tunnels are tightly bonded together.

Description

Technical Field

[0001] This utility model relates to the field of tunnel engineering, specifically to a tunnel lining. Background Technology

[0002] Currently, tunnel construction in China mainly includes tunnel excavation and concrete lining. For large-section tunnels in weak surrounding rock, the excavation process typically involves first excavating the upper section. During excavation, temporary support is provided for the upper section using steel supports and shotcrete. After a certain length of the upper section is excavated, the lower section is excavated, and the steel supports from the upper section are extended to the lower section, with temporary support also provided using shotcrete. Once the lower section has been excavated to a certain length, concrete lining of the tunnel floor begins, followed immediately by concrete lining of the tunnel sidewalls and crown. However, during construction, after the upper section is excavated and supported, significant deformation of the surrounding rock often leads to instability at the tunnel roof. Relying solely on temporary support may pose a risk of collapse, and this risk is further increased during the subsequent excavation of the lower section. Utility Model Content

[0003] To address the problems of existing technologies, this utility model provides a tunnel lining.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A tunnel lining comprising: an upper tunnel section;

[0006] The outer layer of steel reinforcement in the upper half of the tunnel is arched in shape and is located on the upper outer side of the upper half of the tunnel.

[0007] The inner layer of the upper tunnel reinforcement is arched in shape and is located on the inside of the upper tunnel. The inner layer of the upper tunnel reinforcement is located on the side of the outer layer of the upper tunnel reinforcement.

[0008] The lower half of the tunnel is fixed to the lower part of the upper half of the tunnel;

[0009] A lining concrete layer for the upper half of the tunnel is set between the outer layer of steel reinforcement and the inner layer of steel reinforcement in the upper half of the tunnel.

[0010] Furthermore, a wedge-shaped cushion layer is installed between the upper and lower halves of the tunnel. The wedge-shaped cushion layer is a concrete structure, and the height of the wedge-shaped cushion layer towards the inner end is greater than the height towards the outer end. The wedge-shaped cushion layer is located within the wedge space.

[0011] Priority is given to fixing anchoring steel bars inside the upper half of the tunnel lining concrete layer, with the anchoring steel bars facing outwards.

[0012] Priority tunnel lining also includes:

[0013] The outer layer of reinforcing steel in the bottom slab of the lower half-hole is located on the outer side of the bottom of the lower half-hole.

[0014] The inner layer of reinforcement bars in the lower half-tunnel bottom slab is set above the outer layer of reinforcement bars in the lower half-tunnel bottom slab, and the inner layer of reinforcement bars in the lower half-tunnel bottom slab is located on the inner side of the bottom of the lower half-tunnel; a concrete layer for the lower half-tunnel bottom slab is set between the outer layer of reinforcement bars in the lower half-tunnel bottom slab and the inner layer of reinforcement bars in the lower half-tunnel bottom slab.

[0015] The outer layer of steel reinforcement in the sidewall of the lower half-hole is located on the outer side of the lower half-hole.

[0016] The inner layer of reinforcing steel bars in the lower half-hole sidewall is located on one side of the outer layer of reinforcing steel bars in the lower half-hole sidewall, and the inner layer of reinforcing steel bars in the lower half-hole sidewall is located on the inner side of the lower half-hole sidewall.

[0017] A concrete layer for the lower half-hole sidewall is provided between the outer layer of reinforcing steel bars and the inner layer of reinforcing steel bars of the lower half-hole sidewall.

[0018] The outer layer of reinforcing bars of the lower half-hole sidewall is welded and fixed to the bottom of the outer layer of reinforcing bars of the upper half-hole, and the inner layer of reinforcing bars of the lower half-hole sidewall is welded and fixed to the bottom of the inner layer of reinforcing bars of the upper half-hole.

[0019] Compared with the existing technology, the advantages of the utility model are: the structural design of the upper and lower tunnel sections is designed to meet the safety and stability requirements of the tunnel, and the design of the inclined wedge pad and inclined wedge space ultimately enables the concrete of the sidewalls of the upper and lower tunnel sections to be tightly bonded together. Attached Figure Description

[0020] Other features, objects, and advantages of this invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings.

[0021] Figure 1 This is a cross-sectional view of the upper half of the tunnel excavation and support in this utility model.

[0022] Figure 2 This is a cross-sectional view of the reinforced concrete lining of the upper half of the tunnel in this utility model.

[0023] Figure 3 This is a cross-sectional view of the reinforced concrete lining of the upper half of the tunnel in this utility model.

[0024] Figure 4 This is a schematic diagram of the reinforced concrete lining of the lower half of the tunnel in this utility model.

[0025] The components are: 1. Upper tunnel; 2. Upper tunnel excavation line; 3. Upper tunnel steel support; 4. Upper tunnel excavation floor slab; 5. Support cushion layer; 6. Wedge cushion layer; 7. Reinforcing bar embedded holes; 8. Anchoring reinforcement; 9. Load-bearing support; 10. Upper tunnel lining formwork; 11. Upper tunnel outer layer reinforcement; 12. Upper tunnel inner layer reinforcement; 13. Upper tunnel lining concrete layer; 14. Lower tunnel; 15. Lower tunnel steel support; 16. Lower tunnel floor slab outer layer reinforcement; 17. Lower tunnel floor slab inner layer reinforcement; 18. Lower tunnel sidewall outer layer reinforcement; 19. Lower tunnel sidewall inner layer reinforcement; 20. Lower tunnel lining formwork; 21. Lower tunnel floor slab concrete layer; 22. Lower tunnel sidewall concrete layer. Detailed Implementation

[0026] The present invention will be further described in detail below through embodiments. The embodiments are only used to illustrate the present invention and do not limit the scope of the present invention.

[0027] A tunnel lining includes: an upper tunnel 1;

[0028] The outer layer of steel reinforcement 11 in the upper half of the tunnel is arched in shape and is located on the upper outer side of the upper half of the tunnel 1.

[0029] The inner layer of the upper half-hole reinforcement 12 is arched in shape and is located inside the upper half-hole 1. The inner layer of the upper half-hole reinforcement 12 is located on one side of the outer layer of the upper half-hole reinforcement 11.

[0030] An upper tunnel lining concrete layer 13 is provided between the outer layer of reinforcing bars 11 and the inner layer of reinforcing bars 12 of the upper tunnel; preferably, anchoring bars 8 are fixed inside the upper tunnel lining concrete layer 13, with the anchoring bars 8 facing outward; specifically, the anchoring bars 8 are fixed between the upper tunnel lining concrete layer 13 and the rock.

[0031] A wedge-shaped cushion layer 6 is installed between the upper half-hole 1 and the lower half-hole 14. The wedge-shaped cushion layer 6 is a concrete structure with an inclination slope of 10%. The height of the wedge-shaped cushion layer 6 towards the inner end is greater than the height towards the outer end. The wedge-shaped cushion layer 6 is located within the wedge space.

[0032] A tunnel lining also includes:

[0033] Lower half-hole 14 is fixed to the lower part of upper half-hole 1;

[0034] The outer layer of the bottom slab of the lower half-hole is reinforced with steel bar 16, which is located on the outer side of the bottom of the lower half-hole 14.

[0035] The inner layer of the bottom slab reinforcement 17 of the lower half-tunnel is set above the outer layer of the bottom slab reinforcement 16 of the lower half-tunnel bottom slab, and the inner layer of the bottom slab reinforcement 17 of the lower half-tunnel bottom slab is located on the inner side of the bottom of the lower half-tunnel 14; a concrete layer 21 of the bottom slab of the lower half-tunnel is set between the outer layer of the bottom slab reinforcement 16 of the lower half-tunnel bottom slab and the inner layer of the bottom slab reinforcement 17 of the lower half-tunnel bottom slab.

[0036] The outer layer of steel reinforcement 18 in the sidewall of the lower half-hole is set on the outer side of the lower half-hole 14;

[0037] The inner layer of the lower half-hole sidewall reinforcement 19 is set on one side of the outer layer of the lower half-hole sidewall reinforcement 18, and the inner layer of the lower half-hole sidewall reinforcement 19 is located on the inner side of the lower half-hole 14; a concrete layer 22 for the lower half-hole sidewall is set between the outer layer of the lower half-hole sidewall reinforcement 18 and the inner layer of the lower half-hole sidewall reinforcement 19.

[0038] The vertical reinforcing bars of the outer layer 18 and inner layer 19 of the lower half-hole sidewall are lapped and welded to the exposed reinforcing bars at the bottom of the upper half-hole sidewall. Specifically, the outer layer 18 of the lower half-hole sidewall is welded and fixed to the bottom of the outer layer 11 of the upper half-hole, and the inner layer 19 of the lower half-hole sidewall is welded and fixed to the bottom of the inner layer 12 of the upper half-hole.

[0039] This plan also involves a reverse construction method for tunnel lining. After the upper half of the tunnel 1 is excavated, steel supports and anchor-sprayed supports are constructed along the excavation line 2 of the upper half. The steel supports 3 of the upper half are arranged at intervals of 40-50cm for temporary support of the upper half of the tunnel 1. After the temporary support of the upper half of the tunnel 1 is completed, the excavation bottom slab 4 of the upper half is cleaned and leveled, and a support pad 5 is poured in the middle of the excavation bottom slab 4. The support pad 5 is flat, which facilitates the later installation of load-bearing supports 9. Wedge pads 6 are poured on both sides of the excavation bottom slab 4 of the upper half. The slope of the wedge pads 6 is 10%, higher on the inside of the tunnel and lower on the outside. The positions of the vertical reinforcement of the upper half of the tunnel 1 (the bottom positions of the outer layer reinforcement 11 and the inner layer reinforcement 12 of the upper half) are marked on the wedge pads 6. Reinforcement pre-embedded holes 7 are drilled downward at the positions of the vertical reinforcement. The depth of the reinforcement pre-embedded holes 7 is arranged at two intervals of 30cm and 80cm. The inclined wedge cushion layer 6, as a precast body, participates in the formation of the bottom slope of the upper half tunnel lining concrete layer 13 in the later stage. Compared with the formwork, the inclined wedge cushion layer 6 is more convenient for construction operations and also facilitates drilling downwards.

[0040] Horizontal holes are drilled along the side wall of the upper tunnel 1 at intervals of 0.5m. Anchor steel bars 8 are installed in the holes and anchored 100cm into the rock with 50cm exposed outside. The anchor steel bars 8 are then poured into the interior of the upper tunnel lining concrete layer 13, so that the upper tunnel lining concrete layer 13 is anchored to the surrounding rock as one unit.

[0041] Install a load-bearing bracket 9 on the support pad 5, and use the load-bearing bracket 9 to install the outer layer steel bars 11 and the inner layer steel bars 12 of the upper half-hole. Insert the bottom of the outer layer steel bars 11 and the inner layer steel bars 12 of the upper half-hole into the steel bar pre-embedded hole 7. Then fill the gap between the outer layer steel bars 11 and the inner layer steel bars 12 of the upper half-hole and the wall of the steel bar pre-embedded hole 7 with fine sand to prevent cement slurry from entering during concrete pouring.

[0042] After the load-bearing support 9, the outer layer of the upper tunnel reinforcement 11, and the inner layer of the upper tunnel reinforcement 12 are all completed, the upper tunnel lining formwork 10 is installed. After inspection and acceptance, the upper tunnel lining concrete layer 13 is poured.

[0043] Once the strength of the upper tunnel lining concrete layer 13 reaches the required level, it can transfer the deformation stress from the surrounding rock at the top of the upper tunnel to the surrounding rock mass for joint bearing. Moreover, the upper tunnel lining concrete layer 13 has the designed rigidity and strength, which can fully resist the deformation of the weak surrounding rock and ensure the safety of the tunnel.

[0044] After the upper tunnel lining concrete layer 13 is poured and cured for 7 days, the load-bearing support 9 and the upper tunnel lining formwork 10 are removed, and the support pad layer 5 is removed. The lower tunnel 14 is then excavated downwards. The lower tunnel 14 is excavated according to the design cross section. During the excavation process, the steel support anchor spraying support of the lower tunnel is carried out in a timely manner. The steel support 15 of the lower tunnel is fixedly connected to the steel support 3 of the upper tunnel.

[0045] The inclined wedge pads 6 at the bottom of the two side walls of the upper half-hole lining concrete layer 13 are gradually removed to expose the steel bars in the steel bar pre-embedded holes 7. After the inclined wedge pads 6 are removed, an inclined wedge space is formed. The inclined wedge space serves as the contact area between the upper half-hole 1 and the lower half-hole 14. The inclined space is designed to facilitate the later concrete pouring and venting.

[0046] After the excavation of the lower half of the tunnel 14 is completed, the outer layer of reinforcing bars 16, the inner layer of reinforcing bars 17, the outer layer of reinforcing bars 18, and the inner layer of reinforcing bars 19 of the lower half of the tunnel's bottom slab are installed sequentially. The vertical reinforcing bars of the outer layer of reinforcing bars 18 and the inner layer of reinforcing bars 19 of the lower half of the tunnel's side walls must be lapped and welded to the exposed reinforcing bars at the bottom of the upper half of the tunnel's side walls. That is, they must be welded to the bottom reinforcing bars of the outer layer of reinforcing bars 11 and the inner layer of reinforcing bars 12 of the upper half of the tunnel.

[0047] After the reinforcement of the lower half of the tunnel is installed, the formwork 20 for the lining of the lower half of the tunnel is installed, and the concrete layer 21 of the bottom slab of the lower half of the tunnel and the concrete layer 22 of the side wall of the lower half of the tunnel are poured. Since the concrete pouring process is carried out step by step from bottom to top, when the concrete layer 22 of the side wall of the lower half of the tunnel is poured to the top, the concrete is slowly introduced into the side wall at the wedge space using a sloping guide channel (not shown in the figure). During vibration, the air in the concrete is discharged along the pre-reserved slope surface at the top (the top of the wedge space, formed by the wedge pad 6), so that the concrete of the upper and lower half of the tunnel side wall can be tightly bonded together.

[0048] While specific embodiments of this utility model have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of this utility model is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of this utility model, but all such changes and modifications fall within the scope of protection of this utility model.

Claims

1. A tunnel lining, characterized in that, include: Upper half of the hole; The outer layer of steel reinforcement in the upper half of the tunnel is arched in shape and is located on the upper outer side of the upper half of the tunnel. The inner layer of the upper tunnel reinforcement is arched in shape and is located on the inside of the upper tunnel. The inner layer of the upper tunnel reinforcement is located on the side of the outer layer of the upper tunnel reinforcement. A lining concrete layer for the upper half of the tunnel is set between the outer layer of steel reinforcement and the inner layer of steel reinforcement in the upper half of the tunnel. Furthermore, a wedge-shaped pad is installed at the bottom of the upper half of the hole. The wedge-shaped pad is a concrete structure, and the height of the wedge-shaped pad facing inward is greater than the height facing outward. The wedge-shaped pad is located within the wedge space.

2. The tunnel lining according to claim 1, characterized in that, The upper half of the tunnel is lined with concrete layers for fixing anchoring steel bars, which face outwards.

3. The tunnel lining according to claim 2, characterized in that, Tunnel lining also includes: The lower half of the tunnel is fixed to the lower part of the upper half of the tunnel; The outer layer of reinforcing steel in the bottom slab of the lower half-hole is located on the outer side of the bottom of the lower half-hole. The inner layer of reinforcement bars in the lower half-tunnel bottom slab is set above the outer layer of reinforcement bars in the lower half-tunnel bottom slab, and the inner layer of reinforcement bars in the lower half-tunnel bottom slab is located on the inner side of the bottom of the lower half-tunnel; a concrete layer for the lower half-tunnel bottom slab is set between the outer layer of reinforcement bars in the lower half-tunnel bottom slab and the inner layer of reinforcement bars in the lower half-tunnel bottom slab. The outer layer of steel reinforcement in the sidewall of the lower half-hole is located on the outer side of the lower half-hole. The inner layer of reinforcing steel bars in the lower half-hole sidewall is located on one side of the outer layer of reinforcing steel bars in the lower half-hole sidewall, and the inner layer of reinforcing steel bars in the lower half-hole sidewall is located on the inner side of the lower half-hole sidewall.

4. The tunnel lining according to claim 3, characterized in that, A concrete layer for the lower half-hole sidewall is set between the outer layer of reinforcing steel bars and the inner layer of reinforcing steel bars of the lower half-hole sidewall.

5. The tunnel lining according to claim 4, characterized in that, The outer layer of reinforcing bars in the lower half-hole sidewall is welded and fixed to the bottom of the outer layer of reinforcing bars in the upper half-hole, and the inner layer of reinforcing bars in the lower half-hole sidewall is welded and fixed to the bottom of the inner layer of reinforcing bars in the upper half-hole.

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