Tunnel with horseshoe-shaped section

Abstract

The utility model provides a tunnel with a horseshoe-shaped section, which relates to the technical field of tunnel engineering and comprises a tunnel lining structure, the tunnel lining structure comprises a vault, side arches, arch feet and a bottom plate, and the vault, the side arches and the arch feet are sequentially connected to form a tunnel arch supporting part. The tunnel arched supporting part sequentially comprises a secondary lining layer, a waterproof layer and a primary supporting layer from the inside of the horseshoe-shaped section tunnel to the outside; the bottom plate is of a flat bottom structure and located at the bottom of the tunnel lining structure, the bottom plate is horizontally arranged in the cross section of the horseshoe-shaped section tunnel and extends to the arch foot position in the width direction of the horseshoe-shaped section tunnel, and the bottom plate and the secondary lining layer are of an integrally-formed structure. According to the utility model, the stability of the horseshoe-shaped section tunnel can be improved while the construction excavation volume of the horseshoe-shaped section tunnel is reduced.

Description

TECHNICAL FIELD

[0001] The utility model relates to tunnel engineering technical field, specifically, a horseshoe section tunnel. BACKGROUND

[0002] In tunnel engineering construction, the reasonable design of tunnel section has important influence on the stability, construction efficiency and safety of the tunnel. In the related art, the tunnel section forms include circle, ellipse and horseshoe. Among them. The horseshoe section is widely used in highway, railway and water and electricity approach road due to its good bearing capacity and adaptability.

[0003] However, under the condition of IV and worse surrounding rock, the related horseshoe section tunnel still faces certain challenges. For example, due to stress concentration at the arch foot, local deformation may be intensified, affecting the long-term stability of the horseshoe section tunnel. In addition, in the construction process, the horseshoe section tunnel in the related art needs to increase the inverted arch to ensure the stability, and the increase of the inverted arch needs to increase the large excavation amount, which not only increases the construction difficulty, but also may prolong the construction period and increase the engineering cost. SUMMARY

[0004] The problem solved by the utility model is how to reduce the horseshoe section tunnel construction excavation amount while improving the stability of the horseshoe section tunnel.

[0005] To solve the above problems, the utility model provides a horseshoe section tunnel, which comprises a tunnel lining structure, the tunnel lining structure comprises a vault, a side arch, an arch foot and a bottom plate.

[0006] The vault, the side arch and the arch foot are sequentially connected to form a tunnel arched support part, and the tunnel arched support part comprises a secondary lining layer, a waterproof layer and an initial support layer from inside to outside of the horseshoe section tunnel.

[0007] The bottom plate is a flat bottom structure and is located at the bottom of the tunnel lining structure, is horizontally arranged in the transverse section of the horseshoe section tunnel and extends to the arch foot position along the width direction of the horseshoe section tunnel.

[0008] Among them, the bottom plate and the secondary lining layer are integrally formed structures.

[0009] Optionally, the thickness of the bottom plate is 30-50 cm.

[0010] Optionally, the vault, the side arch and the arch foot form a tunnel arched support part, and the tunnel arched support part comprises a secondary lining layer, a waterproof layer and an initial support layer from inside to outside of the horseshoe section tunnel.

[0011] Optionally, the two ends of the waterproof layer, the two ends of the primary support layer and the first surface of the bottom plate are at the same level, and the first surface is a surface of the bottom plate away from the center of the horseshoe-shaped tunnel.

[0012] Optionally, the bottom plate and the secondary lining layer form a closed horseshoe-shaped structure.

[0013] Optionally, a construction joint is arranged in the secondary lining layer, the height of the horizontal line where the construction joint is located is higher than the height of the horizontal line where the arch spring is located, the vertical distance between the construction joint and the arch spring is 0.8-1.2 meters, and a rubber waterstop is arranged at the construction joint.

[0014] Optionally, the bottom plate is formed by pouring concrete, and a steel structure is arranged inside the bottom plate.

[0015] Optionally, a short reinforcement structure is arranged at the connection position between the arch spring and the side arch.

[0016] Optionally, short reinforcement structures are arranged on the inner side and the outer side of the two arch springs of the horseshoe-shaped cross-section tunnel, wherein the short reinforcement structure is composed of 4 steel bars of a preset diameter arranged every meter along the inner side and the outer side of the arch spring.

[0017] Optionally, a drainage ditch and a cable trench are further included.

[0018] The drainage ditch is arranged at one end of the bottom plate in the width direction of the horseshoe-shaped cross-section tunnel and extends in the axial direction of the horseshoe-shaped cross-section tunnel, and is connected with the drainage system of the horseshoe-shaped cross-section tunnel, and the cable trench is arranged at the other end of the bottom plate in the width direction of the horseshoe-shaped cross-section tunnel and extends in the axial direction of the horseshoe-shaped cross-section tunnel.

[0019] Optionally, a pavement structure layer is arranged on the surface of the bottom plate, the pavement structure layer extends in the axial direction of the horseshoe-shaped cross-section tunnel, and the two ends of the pavement structure layer in the width direction of the horseshoe-shaped cross-section tunnel extend to be connected with the drainage ditch and the cable trench, respectively.

[0020] Compared with the prior art, the utility model has the beneficial effects that: the bottom plate located at the bottom of the tunnel lining bottom structure is additionally arranged in the tunnel lining structure, compared with the arch-shaped bottom plate design in the traditional structure, the flat bottom structure can reduce the tunnel excavation depth, reduce the earthwork quantity, thereby reducing the construction difficulty and construction cost; furthermore, the bottom plate extends to the arch foot position along the width direction of the horse hoof-shaped section tunnel, through the horizontal expansion of the bottom plate, the arch foot area obtains additional structural support, thereby reducing the stress concentration problem at the junction of the arch foot and the side arch, reducing the denaturation risk caused by excessive stress in the area, and further improving the long-term stability and durability of the horse hoof-shaped section tunnel; and the tunnel arch support part supporting the tunnel is composed of the arch crown, the side arch and the arch foot, through the mutual cooperation of the secondary lining layer, the waterproof layer and the primary support layer, the carrying capacity and the durability of the tunnel can be improved; finally, the bottom plate and the secondary lining layer are integrally formed, which can simplify the construction process of the tunnel and improve the stability of the tunnel. The utility model can reduce the construction excavation amount of the horse hoof-shaped section tunnel while improving the stability of the horse hoof-shaped section tunnel. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 A structure schematic diagram of a horse hoof-shaped section tunnel is provided for the utility model embodiment.

[0022] Mark explanation: 1-arch crown, 2-side arch, 21-construction joint, 3-arch foot, 4-bottom plate, 51-secondary lining layer, 52-waterproof layer, 53-primary support layer, 6-drainage ditch, 7-cable trench, 8-pavement structure layer. DETAILED DESCRIPTION

[0023] The technical scheme in the utility model embodiments will be described clearly and completely below with reference to the drawings in the utility model embodiments. Obviously, the described embodiments are only part of the embodiments of the utility model, not all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor belong to the protection scope of the utility model.

[0024] In this paper, the "embodiment" means that the specific features, structures or characteristics described in combination with the embodiment can be contained in at least one embodiment of the utility model. The phrase appears at various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment independent of or alternative to other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0025] Tunnel engineering is an important part of transportation, water conservancy and energy infrastructure construction, and the rationality of tunnel cross-section design directly affects the structural stability, construction efficiency and operation safety. At present, the common cross-section forms of tunnels include circular, elliptical and horseshoe-shaped. Among them, the horseshoe-shaped cross-section is widely used in highway, railway and hydropower station access road engineering due to its strong bearing capacity and good space utilization.

[0026] Under the condition of good surrounding rock, the horseshoe-shaped cross-section tunnel can fully exert its structural advantages to ensure the stability of the horseshoe-shaped cross-section tunnel. However, when the horseshoe-shaped cross-section tunnel is located in Class IV and worse surrounding rock (such as soft and broken surrounding rock, high ground stress environment or water-rich stratum), the traditional horseshoe-shaped cross-section structure may face the following challenges during construction and long-term use: 1. Due to the obvious stiffness mutation at the arch foot position of the horseshoe-shaped cross-section, stress concentration easily occurs in the surrounding rock at this area, leading to local deformation intensification and even causing surrounding rock instability, affecting the overall safety of the tunnel; 2. The traditional horseshoe-shaped cross-section usually adopts an arc or inverted arch floor structure, which requires deeper excavation during construction, thereby increasing the earthwork quantity and prolonging the exposure time of the surrounding rock; 3. Due to the poor stability of the surrounding rock, the existing technology usually needs to use anchor rods, steel arches, sprayed concrete and other supporting means to maintain the stability of the tunnel structure, which not only increases the construction difficulty and material cost, but also may cause the construction period to be prolonged, affecting the project progress.

[0027] The utility model aims at providing a novel horseshoe-shaped cross-section tunnel to effectively solve the problems of stress concentration, large excavation quantity and high supporting cost existing in the related art.

[0028] Referring Figure 1 The utility model provides a horseshoe-shaped cross-section tunnel, which comprises a tunnel lining structure, wherein the tunnel lining structure comprises a vault 1, a side arch 2, an arch foot 3 and a floor 4.

[0029] The vault 1, the side arch 2 and the arch foot 3 are sequentially connected to form a tunnel arched supporting part, and the tunnel arched supporting part comprises, from inside to outside of the horseshoe-shaped cross-section tunnel, a secondary lining layer 51, a waterproof layer 52 and a primary supporting layer 53.

[0030] Specifically, the vault 1, the side arch 2 and the arch foot 3 form a tunnel arched supporting part, which is used for supporting the tunnel structure, bearing the surrounding rock pressure and ensuring the stability and durability of the tunnel. In order to enhance the bearing capacity and durability of the tunnel arched supporting part, the tunnel arched supporting part comprises, from inside to outside of the horseshoe-shaped cross-section tunnel, the secondary lining layer 51, the waterproof layer 52 and the primary supporting layer 53, and the structures of the layers cooperate with each other to jointly act so as to improve the overall performance of the horseshoe-shaped cross-section tunnel.

[0031] The initial support layer 53 can be made of one or a combination of several support materials such as concrete, anchor rod, steel mesh, steel frame, etc. The initial support layer 53 arranged after the horseshoe-shaped tunnel excavation can play the roles of closing the rock surface, preventing weathering and loosening, filling the pit concave and fissures, maintaining and improving the integrity of the surrounding rock, helping the surrounding rock to play its own structural role, adjusting the stress distribution of the surrounding rock, preventing stress concentration, controlling the deformation of the surrounding rock, preventing falling blocks, and preventing collapse. In the tunnel arch support part, the initial support layer 53 can bear 20% to 80% of the load released by the surrounding rock according to different categories of surrounding rock.

[0032] The waterproof layer 52 is arranged between the secondary lining layer 51 and the initial support layer 53, and can use ethylene-vinyl acetate copolymer waterproof board and geotextile to prevent water. The ethylene-vinyl acetate copolymer waterproof board can be arranged along the full length and full ring of the concrete section of the horseshoe-shaped tunnel to ensure that the vault 1, the side arch 2, the arch foot 3 and the bottom plate 4 are effectively protected, and the underground water is prevented from penetrating into the secondary lining layer 51. In order to realize the drainage function, a ring-shaped drainage pipe is arranged every 5-8m inside the tunnel to collect fissure water of the surrounding rock and introduce it into the tunnel drainage ditch, thereby reducing the water pressure behind the lining, reducing the risk of leakage, and ensuring the long-term stability and durability of the tunnel.

[0033] The secondary lining layer 51 can use cast-in-place concrete or reinforced concrete structure to improve the overall stiffness and structural integrity. The secondary lining layer 51 can bear 10% to 80% of the load released by the surrounding rock according to different categories of surrounding rock to adapt to the stress requirement under different geological conditions.

[0034] It can be understood that the vault 1, the side arch 2 and the arch foot 3 together form the tunnel arch support part, that is, the vault 1, the side arch 2 and the arch foot 3 all include part of the secondary lining layer, the waterproof layer 52 and the initial support layer 53.

[0035] The horseshoe-shaped cross-section tunnel in the embodiment can effectively adapt to the condition of class IV and worse surrounding rock, enhance the anti-deformation ability of the tunnel, reduce the risk of leakage, and prolong the service life of the horseshoe-shaped cross-section tunnel.

[0036] The bottom plate 4 is a flat bottom structure located at the bottom of the tunnel lining structure, and is horizontally arranged in the transverse section of the horseshoe-shaped cross-section tunnel and extends to the position of the arch foot 3 along the width direction of the horseshoe-shaped cross-section tunnel.

[0037] The bottom plate 4 and the secondary lining layer 51 are integrally formed.

[0038] It should be noted that the arch crown 1 is located at the uppermost part of the horseshoe section tunnel, and the cross section thereof is usually in an arc shape to adapt to the distribution characteristics of the surrounding rock pressure. The arch crown 1 can bear the vertical load from the surrounding rock and gradually transmit the load to the side arch 2 and the arch foot 3, thereby reducing the local stress concentration phenomenon and improving the stability of the horseshoe section tunnel.

[0039] The side arch 2 is located below the arch crown 1 and extends along the two sides of the horseshoe section tunnel to the arch foot 3. The main function of the side arch 2 is to disperse and transmit the load of the arch crown 1 and resist the pressure from the surrounding rock on the two sides of the horseshoe section tunnel. The side arch 2 usually has an arc shape or a compound curve shape to optimize the stress performance of the horseshoe section tunnel.

[0040] The arch foot 3 is located at the junction of the side arch 2 and the bottom plate 4. The arch foot 3 is a key node for load transmission of the horseshoe section tunnel, directly bears the load from the arch crown 1 and the side arch 2, and disperses the load to the bottom plate 4 and the foundation. Since the arch foot 3 is prone to form a stress concentration area. Therefore, the utility model adds the bottom plate 4 to support the arch foot 3, reduces the stress concentration phenomenon at the arch foot 3, reduces the construction excavation amount, and improves the stability and construction efficiency of the tunnel structure.

[0041] The structure that the bottom plate 4 and the secondary lining layer 51 are integrally formed can effectively simplify the construction process of the bottom plate and the secondary lining layer, and further improve the stability of the horseshoe section tunnel due to the improvement of the overall performance of the horseshoe section tunnel.

[0042] Compared with the prior art, the utility model has the beneficial effects that: a bottom plate is added at the bottom of the tunnel lining structure, compared with the traditional arch-shaped bottom plate design, the flat bottom structure can reduce the tunnel excavation depth, reduce the earthwork amount, thereby reducing the construction difficulty and construction cost; furthermore, the bottom plate extends to the arch foot position along the width direction of the horseshoe section tunnel, the horizontal expansion of the bottom plate provides additional structural support to the arch foot area, thereby reducing the stress concentration problem at the junction of the arch foot and the side arch, reducing the risk of deformation of the area due to excessive stress, and further improving the long-term stability and durability of the horseshoe section tunnel; and the tunnel arch support part supporting the tunnel is composed of the arch crown, the side arch and the arch foot, which can improve the carrying capacity and durability of the tunnel through the cooperation of the secondary lining layer, the waterproof layer and the primary support layer; finally, the integrally formed structure of the bottom plate and the secondary lining layer can simplify the construction process of the tunnel and improve the stability of the tunnel. The utility model can reduce the construction excavation amount of the horseshoe section tunnel while improving the stability of the horseshoe section tunnel.

[0043] In one embodiment, the thickness of the bottom plate 4 is 30-50 cm.

[0044] Specifically, the thickness of the bottom plate 4 can also be set in reference to the thickness of the secondary lining layer 51 to ensure the stress balance of the overall structure of the horseshoe-shaped cross-section tunnel and optimize the coordination between the secondary lining layer 51 and the bottom plate 4; in the case of good surrounding rock conditions, the thickness of the bottom plate 4 can be selected in the range close to 30 centimeters to reduce the amount of concrete and reduce construction costs, while meeting the structural stress requirements. In the case of soft surrounding rock or large tunnel load, the thickness of the bottom plate 4 can be selected in the range close to 50 centimeters to enhance the anti-deformation ability of the bottom plate 4 and improve the safety and durability of the overall tunnel.

[0045] In an embodiment, the two ends of the waterproof layer 52, the two ends of the primary support layer 53 and the first surface of the bottom plate 4 are at the same level, and the first surface is a surface of the bottom plate 4 away from the center of the horseshoe-shaped tunnel.

[0046] Specifically, the first surface of the waterproof layer 52, the primary support layer 53 and the bottom plate 4 are at the same level, which helps to ensure the flatness and stability of the internal structure of the horseshoe-shaped cross-section tunnel, and avoid structural deformation or stress concentration caused by inconsistent levels. This embodiment can enhance the compactness of the structure of the horseshoe-shaped cross-section tunnel, thereby enhancing the load-bearing capacity and durability of the horseshoe-shaped cross-section tunnel.

[0047] In an embodiment, the bottom plate 4 and the secondary lining layer 51 form a closed horseshoe-shaped structure.

[0048] Specifically, the bottom plate 4 and the secondary lining layer 51 can be integrally formed to form a closed horseshoe-shaped structure, which can effectively disperse the stress of the arch foot 3, reduce the risk of excessive local stress of the arch foot 3, and avoid the possible local settlement cracks of the arch foot 3. On the other hand, the closed horseshoe-shaped structure formed by the combination of the bottom plate 4 and the secondary lining layer 51 can constrain the deformation of the arch foot 3 under stress, especially during the operation of the horseshoe-shaped cross-section tunnel. The bottom plate 4 bears the pressure from the arch foot 3 to maintain the stability of the arch foot 3 region, thereby preventing excessive deformation of the arch foot 3 and ensuring the durability of the horseshoe-shaped cross-section tunnel, avoiding safety hazards caused by structural deformation.

[0049] In an embodiment, referring to Figure 1 , a construction joint 21 is arranged in the secondary lining layer 51, the height of the horizontal line where the construction joint 21 is located is higher than the height of the horizontal line where the arch foot 3 is located, and the vertical distance between the construction joint 21 and the arch foot 3 is A, the value of A is in the range of 0.8 meters to 1.2 meters, and a rubber waterstop is arranged at the construction joint 21.

[0050] It needs to be explained that in the related art, the construction joint 21 is usually arranged at the intersection of the spandrel 3 and the side arch 2, stress concentration phenomenon is easy to occur, deformation occurs at the construction joint 21, and then the stability of the horseshoe-shaped cross-section tunnel is damaged. In the embodiment, the height of the horizontal line where the construction joint 21 is located is higher than the height of the horizontal line where the spandrel 3 is located. By arranging the construction joint 21 at a vertical distance A of the spandrel 3, the value range of A is 0.8 meters to 1.2 meters, not only can the damage of the construction joint 21 caused by stress concentration be avoided, but also the structural strength and stability of the construction joint 21 can be ensured.

[0051] Further, by arranging the rubber waterstop at the construction joint 21, water can be effectively prevented from penetrating into the horseshoe-shaped cross-section tunnel through the construction joint 21, thereby ensuring the waterproof effect of the horseshoe-shaped cross-section tunnel.

[0052] In the embodiment, the construction joint 21 in the secondary lining layer 51 is designed to effectively prevent structural damage caused by excessive stress by reasonably avoiding the stress concentration area at the intersection of the spandrel 3 and the side arch 2. At the same time, the cooperation of the construction joint 21 and the rubber waterstop ensures the waterproof performance and structural stability of the horseshoe-shaped cross-section tunnel, and prolongs the service life of the horseshoe-shaped cross-section tunnel.

[0053] In an embodiment, the bottom plate 4 is formed by pouring concrete, and a steel structure is arranged inside the bottom plate 4.

[0054] The floor in the embodiment is formed by pouring concrete, and is combined with a reasonably configured steel structure, which ensures that the bottom plate 4 has sufficient strength, stiffness and durability to adapt to various loads borne by the tunnel during use. On the other hand, the bottom plate 4 is formed by pouring concrete, and a steel structure is arranged inside the bottom plate 4, that is, the bottom plate 4 and the tunnel arch support part are both formed by pouring concrete and are internally provided with a steel structure, so that the bottom plate 4 and the tunnel arch support part can be integrally constructed, which not only improves the supporting effect of the bottom plate 4 on the spandrel 3, but also speeds up the construction efficiency of the horseshoe-shaped cross-section tunnel.

[0055] In an embodiment, a short reinforcement structure is arranged at the connection position of the spandrel 3 and the side arch 2.

[0056] It needs to be explained that the short reinforcement structure is arranged at the connection position of the spandrel 3 and the side arch 2, which is usually a region where stress concentration is more obvious in the tunnel structure. Since the intersection of the spandrel 3 and the side arch 2 may generate a large stress when the horseshoe-shaped cross-section tunnel is affected by external loads, earthquakes or other dynamic factors, reinforcing the steel at this position helps to disperse stress and enhance the structural stability of the position.

[0057] In an embodiment, the inner side and the outer side of the two arch feet of the horse-shoe section tunnel are arranged with a short reinforcement structure, wherein the short reinforcement structure is composed of 4 steel bars of a preset diameter arranged per meter along the inner side and the outer side of the arch feet.

[0058] Specifically, the embodiment further limits the short reinforcement structure, and by arranging the short reinforcement structure on the inner side and the outer side of the two arch feet 3, the tensile, compressive and shear capacity of the arch feet 3 part can be effectively enhanced. The inner side steel bars enhance the tensile performance of the arch feet 3, preventing cracks when the tensile force is too large; the outer side steel bars enhance the compressive and shear capacity, avoiding instability or deformation of the arch feet 3 under external load. The uniform arrangement of the steel bars can effectively disperse the stress at the arch feet 3 part, avoiding local stress concentration, thereby improving the overall stability and durability of the tunnel.

[0059] In an embodiment, the short reinforcement structure is composed of 4 steel bars of 28 mm diameter arranged per meter along the inner side and the outer side of the arch feet 3, wherein the spacing between the short bars and the spacing between the main bars are the same, both being a longitudinal spacing of 25 cm.

[0060] In an embodiment, it further comprises a drainage ditch 6 and a cable trench 7;

[0061] The drainage ditch 6 is arranged at one end of the bottom plate 4 in the width direction of the horse-shoe section tunnel and extends in the axial direction of the horse-shoe section tunnel, and is connected with the drainage system of the horse-shoe section tunnel; the cable trench 7 is arranged at the other end of the bottom plate 4 in the width direction of the horse-shoe section tunnel and extends in the axial direction of the horse-shoe section tunnel.

[0062] Specifically, the drainage ditch 6 is arranged in the axial direction and located at one end of the bottom plate 4 in the width direction of the horse-shoe section tunnel, usually close to the inner side wall of the tunnel, so as to collect the seepage, rainwater or other drainage in the tunnel; the cable trench 7 is arranged in the axial direction of the tunnel and located at one end of the bottom plate 4 in the width direction of the horse-shoe section tunnel, symmetrically distributed with the drainage ditch 6 along the longitudinal axis of the bottom plate 4; wherein the arrangement of the drainage ditch 6 ensures that the drainage system in the tunnel can operate normally, avoiding the influence of accumulated water on the cable trench 7 and the internal environment of the tunnel; the independent arrangement of the cable trench 7 can effectively protect the cables from water erosion, and facilitate the later maintenance and repair, thereby improving the operation safety and reliability of the tunnel.

[0063] The embodiment arranges the drainage ditch 6 and the cable trench 7 on both sides of the tunnel bottom plate 4, which not only ensures the drainage capacity of the horse-shoe section tunnel, but also provides reliable support for the laying of power communication lines, thereby improving the overall functionality and durability of the horse-shoe section tunnel.

[0064] In an embodiment, a road surface structure layer 8 is arranged on the surface of the bottom plate 4, and extends along the axial direction of the horse-shoe section tunnel, and extends to the drainage ditch 6 and the cable trench 7 at two ends in the width direction of the horse-shoe section tunnel.

[0065] Specifically, the road surface structure layer 8 is arranged on the entire surface of the bottom plate 4, forming a continuous and flat driving or passing area, improving the comfort and safety of the horse-shoe section tunnel. One side of the road surface structure layer 8 is connected with the drainage ditch 6, so that the seepage or rainwater in the horse-shoe section tunnel can flow into the drainage ditch 6 smoothly, preventing the accumulated water from affecting the driving safety. The other side of the road surface structure layer 8 is connected with the cable trench 7, providing protection for the cable trench 7, and ensuring that the cover plate of the cable trench 7 can be removed, facilitating the later maintenance.

[0066] The embodiment ensures that the horse-shoe section tunnel has good bearing capacity, drainage performance and cable protection effect by arranging the road surface structure layer 8 on the surface of the bottom plate 4 and reasonably arranging the connection relationship between the drainage ditch 6 and the cable trench 7, thereby improving the overall use performance and durability of the horse-shoe section tunnel.

[0067] Although the utility model discloses as above, the protection scope of the utility model is not limited to this only. The person skilled in the art can make various changes and modifications without departing from the spirit and scope of the utility model, and these changes and modifications will all fall into the protection scope of the utility model.

Claims

1. A tunnel having a horse-shoe cross-section, characterized in that, The tunnel lining structure comprises a vault (1), a side arch (2), a springing (3) and a floor (4); The vault (1), the side arch (2) and the springing (3) are sequentially connected to form a tunnel arch support part, which comprises, from inside to outside of the horse-shoe cross-section tunnel, a secondary lining layer (51), a waterproof layer (52) and a primary support layer (53); The floor (4) is a flat bottom structure, located at the bottom of the tunnel lining structure, horizontally arranged in the cross-section of the horse-shoe cross-section tunnel and extending to the position of the springing (3) along the width direction of the horse-shoe cross-section tunnel. The floor (4) and the secondary lining layer (51) are integrally formed.

2. The horseshoe-shaped tunnel according to claim 1, characterized in that The thickness of the floor (4) is 30-50 cm.

3. The horseshoe-shaped tunnel according to claim 1, wherein The two ends of the waterproof layer, the two ends of the primary support layer and the first surface of the floor are at the same level, and the first surface is the surface of the floor away from the center of the horse-shoe tunnel.

4. The horseshoe-shaped tunnel according to claim 1, wherein The floor (4) and the secondary lining layer (51) form a closed horse-shoe structure.

5. The horseshoe-shaped tunnel according to claim 4, wherein A construction joint (21) is arranged in the secondary lining layer (51), the height of the horizontal line where the construction joint (21) is located is higher than the height of the horizontal line where the springing (3) is located, and the vertical distance between the construction joint (21) and the springing (3) is 0.8-1.2 m, and a rubber waterstop is arranged at the construction joint.

6. The horseshoe-shaped tunnel according to claim 4, wherein The floor (4) is formed by pouring concrete, and a steel structure is arranged inside the floor (4).

7. The horseshoe-shaped tunnel according to claim 6, characterized in that A short reinforcement structure is arranged at the connection position between the springing (3) and the side arch (2).

8. The horseshoe-shaped tunnel according to claim 7, characterized in that Short reinforcement structures are arranged on the inner side and the outer side of the two springings (2) of the horse-shoe cross-section tunnel, wherein the short reinforcement structure is composed of 4 steel bars with a preset diameter arranged every meter along the inner side and the outer side of the springing (3).

9. The horseshoe-shaped tunnel of claim 1, wherein A drainage ditch (6) and a cable trench (7) are further included; The drainage ditch (6) is arranged at one end of the floor (4) in the width direction of the horse-shoe cross-section tunnel and extends in the axial direction of the horse-shoe cross-section tunnel, and is connected with the drainage system of the horse-shoe cross-section tunnel, and the cable trench (7) is arranged at the other end of the floor (4) in the width direction of the horse-shoe cross-section tunnel and extends in the axial direction of the horse-shoe cross-section tunnel.

10. The horseshoe-shaped tunnel according to claim 9, wherein A road surface structure layer (8) is arranged on the surface of the floor (4), which extends in the axial direction of the horse-shoe cross-section tunnel, and the two ends thereof in the width direction of the horse-shoe cross-section tunnel extend to the drainage ditch (6) and the cable trench (7), respectively.

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