Shield tunnel anti-floating structure

Abstract

The utility model relates to a shield tunnel anti-floating structure which comprises a shield tunnel, a grouting body is arranged outside the shield tunnel, a mattress layer is arranged outside the grouting body, and a plurality of cement-soil piles are formed outside the mattress layer in a grouting mode. An embedded steel plate is arranged in the shield tunnel; a plurality of embedded anti-floating components connected with the embedded steel plate are arranged on the shield tunnel in a protruding mode, and the anti-floating components are sequentially arranged in the grouting body, the mattress layer and the cement-soil piles in a penetrating mode. The cushion layer can reduce the risk of segment slab staggering or differential settlement between the adjacent grouting holes, and deformation of the tunnel due to uneven stress is prevented; the anti-floating component plays a role in preventing the tunnel from floating upwards, and the shield tunnel anti-floating structure not only has a good tunnel anti-floating effect, but also prevents the tunnel from settling and deforming.

Description

Technical Field

[0001] The utility model belongs to the technical field of underground tunnel engineering, and particularly relates to an anti-floating structure of a shield tunnel. Background Art

[0002] The floating of shield tunnels is a common problem during the construction and operation of tunnels. During the construction of shield tunnels, if the attitude control of the shield machine is poor in water-rich strata or inert slurry is used for synchronous grouting, serious floating problems are likely to occur. Similarly, during the operation of the subway, the reduction of the overburden pressure will inevitably increase the risk of tunnel floating due to the unloading from above. The floating of shield tunnels has an important impact on the safety of tunnel structures, which is specifically manifested as follows: 1) the segments invade the tunnel construction limit, increase the axis deviation, and affect the functional use; 2) the segments between the rings are misaligned, resulting in shearing of the bolts and cracking of the segments. In severe cases, the bolts may even be sheared off, forming through cracks, affecting the safety of the structure; 3) the water stop between the rings fails, resulting in water leakage at the joints, and in severe cases, soil and sand may even surge, threatening the safety of tunnel operations. For example, an anti-floating shield segment structure shown in the comparative document CN219061668U can solve the problem of poor waterproofing effect of the anti-floating structure of the shield segment, but it cannot solve the problem of tunnel settlement and deformation. Utility Model Content

[0003] In order to solve the problems of tunnel anti-floating and tunnel settlement deformation at the same time, the utility model invents a shield tunnel anti-floating structure which has good tunnel anti-floating effect and prevents tunnel settlement deformation.

[0004] A shield tunnel anti-floating structure includes a shield tunnel, a grouting body is arranged outside the shield tunnel, a cushion layer is arranged outside the grouting body, and a plurality of cement soil piles are formed by grouting outside the cushion layer; a pre-buried steel plate is arranged inside the shield tunnel; and a plurality of implanted anti-floating components connected to the pre-buried steel plate are protruding from the shield tunnel, and the anti-floating components are sequentially passed through the grouting body, the cushion layer and the cement soil piles. The grouting body and the cushion layer are arranged outside the shield tunnel, close to the outer edge of the tunnel structure, and have the function of reinforcing the tunnel; the cushion layer can also reduce the risk of misalignment or differential settlement of pipe segments between adjacent grouting holes, and prevent the tunnel from being deformed due to uneven force; the anti-floating component plays a role in preventing the tunnel from floating up, and the anti-floating component passes through the pre-buried steel plate, the shield tunnel, the grouting body, the cushion layer and the cement soil piles in sequence, and plays a role in connecting the components.

[0005] As a preferred embodiment, the radian of the embedded steel plate is consistent with that of the shield tunnel; the embedded steel plate is provided with a mounting hole for inserting the anti-floating member; the embedded steel plate is fixedly connected to the shield tunnel. The radian of the embedded steel plate is consistent with that of the shield tunnel, and there is no gap between them, thereby ensuring the sealing between the two, preventing moisture from entering, and making the connection between the two more secure; mounting holes are pre-designed on the embedded steel plate, and the anti-floating member can be installed in the mounting hole; high-strength bolts can be used to fix the embedded steel plate and the shield tunnel together.

[0006] Preferably, the cement soil pile includes a vertical cement soil pile and an inclined cement soil pile, which are connected to the cushion layer, and the cement soil pile is arranged outside the cushion layer. The cement soil pile is a structure in which the pile axis passes through the center of the shield tunnel structure, and can be divided into a vertical cement soil pile and an inclined cement soil pile according to the angle between the pile axis and the horizontal direction; the cement soil pile is arranged outside the device, can be bonded to the surrounding soil, can be opened at any angle, and can improve the anti-floating effect of the anti-floating structure.

[0007] Preferably, a plurality of grouting holes are arranged in the shield tunnel; the grouting holes are arranged one-to-one corresponding to the embedded steel plates and the anti-floating components. The positions of the grouting holes correspond one-to-one to the embedded steel plates and the anti-floating components, the anti-floating components are implanted in the grouting holes, and the grouting operation is also performed.

[0008] Preferably, the gap between the grouting hole and the anti-floating component is filled with fillers; a rubber ring is provided between the upper end of the anti-floating component and the shield tunnel. The gap between the grouting hole and the anti-floating component is filled with polyurethane and micro-expanded fine stone concrete respectively, and a micro-expanded waterproof rubber ring is provided on the outer cover of the anti-floating component to ensure the water-stopping effect of the grouting hole and prevent water leakage in the shield tunnel.

[0009] Preferably, a blowout prevention device is installed on the embedded steel plate, and a water stop valve is provided on the blowout prevention device. Installing the blowout prevention device on the embedded steel plate can avoid the risk of soil and sand surge caused by high water and soil pressure outside the shield tunnel during the construction phase, thereby protecting the safety of the tunnel inside.

[0010] Preferably, a plurality of grouting holes are evenly distributed on the shield tunnel and are symmetrically arranged. The even distribution of the grouting holes also means that the distribution of the anti-floating components and cement soil piles in the device is even; the symmetrical arrangement can use the friction between the cement soil piles and the surrounding soil to offset the buoyancy of the shield tunnel, effectively enhancing the connection between the shield tunnel and the surrounding soil, avoiding the floating of the shield tunnel, and thus avoiding the shield tunnel from being damaged.

[0011] Preferably, the thickness of the grouting body is 100 mm to 150 mm. The grouting body is constructed simultaneously with the shield tunnel.

[0012] Preferably, the diameter of the vertical cement soil pile is 800mm to 1500mm; the diameter of the inclined cement soil pile is 600mm to 1200mm. The cement soil pile is bonded to the surrounding soil, and the friction generated between the two can offset the buoyancy of the shield tunnel.

[0013] As a preferred option, an advanced construction technology, the high-pressure grouting system construction technology in the shield tunnel, is adopted to ensure that the diameter of the anti-floating component will not be too small, reduce the number of required anti-floating components, achieve better anti-floating effects, and reduce engineering costs during construction.

[0014] The beneficial effects of the utility model are as follows: a shield tunnel anti-floating structure can not only play the role of tunnel anti-floating, but also prevent tunnel settlement and deformation, and play the role of double-line control; moreover, it also reduces engineering costs and prolongs the service life of the utility model. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is the overall structural diagram of the utility model.

[0016] Figure 2 It is a schematic diagram of the anchor connection between the anti-floating component and the shield tunnel in the utility model.

[0017] Figure 3 It is a schematic diagram of the construction process of the utility model.

[0018] Figure 4 It is a schematic diagram of the detailed node construction process of the utility model.

[0019] The numbers in the figure are: 1. shield tunnel; 2. grouting body; 3. cushion layer; 4. vertical cement soil pile; 5. inclined cement soil pile; 6. anti-floating member; 7. embedded steel plate; 8. grouting hole; 9. filler; 10. rubber ring; 11. concrete; 12. bolt; 13. weld; 14. blowout preventer; 15. drill rod; 16. cement soil pile. DETAILED DESCRIPTION

[0020] Embodiment 1:

[0021] As the instruction manual Figure 1As shown in the figure, a shield tunnel anti-floating structure is provided, wherein a grouting body 2 is provided outside the shield tunnel, a cushion layer 3 is provided outside the grouting body, and a plurality of cement soil piles 16 are formed by grouting outside the cushion layer; a pre-buried steel plate 7 is provided inside the shield tunnel; a plurality of embedded anti-floating components 6 connected to the pre-buried steel plate are provided protrudingly on the shield tunnel, and the anti-floating components are sequentially penetrated through the grouting body, the cushion layer and the cement soil pile. The arc of the pre-buried steel plate is consistent with that of the shield tunnel; the pre-buried steel plate is provided with a mounting hole, and the pre-buried steel plate is provided with a mounting hole for penetrating the anti-floating component; the pre-buried steel plate is fixedly connected to the shield tunnel. The cement soil piles include a plurality of vertical cement soil piles 4 and a plurality of inclined cement soil piles 5, the vertical cement soil piles 4 and the inclined cement soil piles 5 are respectively connected to the cushion layer, and the cement soil piles are provided outside the cushion layer. A plurality of grouting holes 8 are provided in the shield tunnel; the grouting holes are provided one by one correspondingly to the pre-buried steel plates and the anti-floating components. The gap between the grouting hole and the anti-floating member is filled with a filler 9 of polyurethane; a rubber ring 10 is provided between the upper end of the anti-floating member and the shield tunnel. A blowout prevention device 14 is installed on the embedded steel plate, and a water stop valve is provided on the blowout prevention device. Several grouting holes are evenly and symmetrically distributed on the shield tunnel. The thickness of the grouting body is 100mm to 150mm. The diameter of the vertical cement soil pile is 800mm to 1500mm; the diameter of the inclined cement soil pile is 600mm to 1200mm.

[0022] As the instruction manual Figure 3 With the instruction manual Figure 4As shown in, before the grouting operation, the embedded steel plate 7 with the mounting hole is fixed to the shield tunnel 1 with high-strength bolts, the position of the mounting hole on the embedded steel plate corresponds to the position of the grouting hole 8, and the construction mark is made; then, a spraying device 14 is installed on the embedded steel plate; after the spraying device is installed, the water stop valve is opened, and the drill rod 15 is implanted into the spraying device using the TJS method equipment, and the drilling construction can begin; the size of the drill rod is adapted to the size of the grouting hole; the grouting hole is 50 cm away from the outer surface of the shield tunnel, and the drill rod first breaks through 50 mm of the shield tunnel composed of concrete before the grouting operation is performed; the TJS method is used to sequentially construct vertical cement soil piles 4, inclined cement soil piles 5 and a cushion layer 3; in the vertical cement soil piles, inclined cement soil piles, and cushion layers Before the cement soil is initially set, the water stop valve in the spraying device is open, the anti-floating component 6 is implanted into the grouting hole, and the water stop valve is closed; after the cement soil pile and the anti-floating component are formed, the drill rod is pulled out and the water stop valve in the spraying device is closed; after the cement soil curing period is over and the design requirements are met, the water stop valve is removed; the gap between the grouting hole and the anti-floating component is first filled with filler 9 polyurethane, and the filling height is preferably 100mm to 150mm; then a layer of rubber water stop ring 10 is placed on the anti-floating component; finally, the micro-expansion fine stone concrete 11 is used to backfill the remaining gap, and the height of the filled micro-expansion fine stone concrete should be higher than the mark on the shield tunnel; finally, the end of the anti-floating component is welded to the embedded steel plate, and the welding should be fully welded along the anti-floating component, and the height of the weld 13 is not less than 8mm. The cement soil pile in the utility model has a large pile depth and a large pile diameter, and can be constructed on the top of the tunnel. Only a shorter anti-floating component is required to achieve the anti-floating requirements, which can reduce the engineering cost.

[0023] As the instruction manual Figure 2 As shown in , the embedded steel plate 7 is provided with a mounting hole with the same diameter as the grouting hole 8; the anti-floating member 6 passes through the mounting hole, and the grouting operation and the reinforcing bar planting operation are completed through the grouting hole; the embedded steel plate and the shield tunnel are connected together by high-strength bolts; the required holes are processed in advance to reduce the impact of the secondary opening on the segment structure. The embedded steel plate and the shield tunnel 1 have the same curvature, and the two can be tightly connected; high-strength bolts are used to connect the two to ensure that the connection between the two is firm; the embedded steel plate is a curved steel plate.

[0024] The embedded steel plate 7 and the segments in the shield tunnel 1 are integrally formed to reduce damage to the shield tunnel during construction, avoid affecting the overall quality and safety of the tunnel, and avoid affecting the waterproof performance and durability of the tunnel.

[0025] The end of the anti-floating member 6 is welded to the embedded steel plate 7, and the height of the weld 13 is not less than 8 mm. Full welding can ensure the firmness of the connection between the anti-floating member and the embedded steel plate without gaps, thereby avoiding water leakage and seepage. The other end of the anti-floating member is located in the vertical cement soil pile 4 and the inclined cement soil pile 5, thereby ensuring the integrity of the anti-floating member and the shield tunnel 1.

[0026] The positions of the anti-floating member 6, the embedded steel plate 7, and the grouting hole 8 correspond to each other; a circular hole with the same diameter as the anti-floating member is reserved on the embedded steel plate, so that the anti-floating member can enter the cement soil pile 16 through the circular hole; wherein, the diameter of the grouting hole arranged on the shield tunnel 1 is 50 mm, and the diameter of the anti-floating member is slightly smaller than the diameter of the grouting hole; the anti-floating member is covered with a micro-expansion waterproof rubber ring 10; the gap between the anti-floating member and the grouting hole is filled with filler 9 polyurethane and micro-expansion fine stone concrete 11; in this way, the waterproof effect at the grouting hole can be guaranteed to avoid water leakage in the shield tunnel; water leakage will affect the structural strength of the utility model and shorten its service life.

[0027] There are 10 anti-floating components 6, which are symmetrically arranged in the upper and lower positions; there are also 10 cement soil piles 16, which are corresponding to the anti-floating components one by one; there are two vertical cement soil piles 4 and 8 inclined cement soil piles 5; among which, the length of the vertical cement soil pile is greater than that of the inclined cement soil pile; and the diameter of the vertical cement soil pile is greater than that of the inclined cement soil pile; the diameter of the vertical cement soil pile is 1000mm, and the diameter of the inclined cement soil pile is 800mm; the material of the anti-floating component is steel bar; the cement soil pile is bonded to the surrounding soil, and the opening angle of the cement soil pile can be arbitrarily opened, and the angle and specification of the cement soil pile can be determined according to the actual environmental conditions of the surrounding soil; the cement soil pile and the anti-floating component form a stable anti-floating system, and the cement soil pile is bonded to the surrounding soil, which increases the friction between the utility model and the surrounding soil, thereby playing a role in anti-floating of the shield tunnel; the pile axis of the cement soil pile passes through the center of the shield tunnel structure.

[0028] The cushion layer 3 is located on the top of the radial cement soil pile 16, has a certain thickness, and is a reinforcement body close to the edge of the grouting body 2 outside the shield tunnel 1; the cushion layer arranged between the cement soil piles can reduce the risk of segment misalignment or differential settlement between adjacent grouting holes.

[0029] During construction, a blowout prevention device 14 is installed on the embedded steel plate 7, and a water stop valve is provided on the blowout prevention device. Installing the blowout prevention device on the embedded steel plate can avoid the risk of soil and sand surge caused by high water and soil pressure outside the shield tunnel during the construction stage, and protect the safety of the tunnel inside.

[0030] The end of the anti-floating member 6 is welded to the embedded steel plate 7 by a full-circle welding operation, and the height of the weld 13 is 10 mm; the gap between the grouting hole 8 and the anti-floating member is filled with a filler 9 polyurethane, and the filling height is 150 mm.

[0031] Embodiment 2:

[0032] As the instruction manual Figure 1 As shown in the figure, a shield tunnel anti-floating structure is provided, wherein a grouting body 2 is provided outside the shield tunnel, a cushion layer 3 is provided outside the grouting body, and a plurality of cement soil piles 16 are formed by grouting outside the cushion layer; a pre-buried steel plate 7 is provided inside the shield tunnel; a plurality of embedded anti-floating components 6 connected to the pre-buried steel plate are provided protrudingly on the shield tunnel, and the anti-floating components are sequentially penetrated through the grouting body, the cushion layer and the cement soil pile. The arc of the pre-buried steel plate is consistent with that of the shield tunnel; the pre-buried steel plate is provided with a mounting hole, and the pre-buried steel plate is provided with a mounting hole for penetrating the anti-floating component; the pre-buried steel plate is fixedly connected to the shield tunnel. The cement soil piles include a plurality of vertical cement soil piles 4 and a plurality of inclined cement soil piles 5, the vertical cement soil piles 4 and the inclined cement soil piles 5 are respectively connected to the cushion layer, and the cement soil piles are provided outside the cushion layer. A plurality of grouting holes 8 are provided in the shield tunnel; the grouting holes are provided one by one correspondingly to the pre-buried steel plates and the anti-floating components. The gap between the grouting hole and the anti-floating component is filled with a filler 9 of polyurethane; a rubber ring 10 is provided between the upper end of the anti-floating component and the shield tunnel. A blowout prevention device 14 is installed on the embedded steel plate, and a water stop valve is provided on the blowout prevention device. Several grouting holes are evenly and symmetrically distributed on the shield tunnel.

[0033] The diameter of the vertical cement soil pile 4 is 1500 mm, and the diameter of the inclined cement soil pile 5 is 1200 mm; the larger the diameter of the cement soil pile 16 is, the larger the contact area with the surrounding soil is, so the greater the friction is, and the better the anti-floating effect is.

[0034] The grade of the slightly expanded fine stone concrete 11 is higher than the grade of the concrete constituting the shield tunnel 1 , and the material of the slightly expanded fine stone concrete can be concrete with a strength grade of C55 or above.

[0035] The material of the anti-floating component 6 can be a steel pipe, an anchor rod, or a micropile. When a steel pipe is selected as the material of the anti-floating component, an anti-corrosion coating can be applied to the surface of the steel pipe, which is beneficial to improving the corrosion resistance of the steel pipe; when an anchor rod is selected as the anti-floating component, a large-head anchor rod can be selected, which can significantly improve the bearing capacity within the limited length of the anchor body, and can be combined with the setting of soil nails to improve the shear strength of the soil at the bottom of the tunnel. The combination of the large-head anchor rod and the soil nails can integrate the tunnel lining segment with the soil at the bottom of the tunnel, greatly improving the anti-floating ability of the shield tunnel under the influence of factors such as geology, water, and synchronous slurry.

[0036] No cracks penetrating from inside to outside or gaps with a width greater than 0.2 mm are allowed in shield tunnel 1. At the same time, the allowable deviation of the plane position and elevation of the tunnel axis must be controlled within ±50 mm.

[0037] The structure of the shield tunnel 1 is strengthened to meet the requirements of strength, durability and waterproofing; reinforcing ribs can be added; longitudinal connecting bolts of Class B M27 and performance level 8.8 are selected to strengthen the longitudinal stiffness of the shield tunnel; the shield tunnel can use concrete with a water-resistance grade of P12; the rubber ring 10 is sealed with a water-swelling rubber ring; the concrete 11 can also use polymer waterproof mortar; the weld 13 can also be replaced by a plastic protective cover.

[0038] The grouting liquid is cement slurry with a water-cement ratio of 1:1, and the grouting is carried out at intervals. The grouting pressure is controlled at 0.5-1.0MPa and optimized on site according to the grouting test. The reinforced soil must have good self-support, sealing and strength, and the unconfined compressive strength must be greater than 0.8MPa.

[0039] The anti-floating component 6 is designed with flower holes, which can increase the friction between the anti-floating component and the rubber ring 10 and concrete 11 that play a sealing role, thereby preventing the shield tunnel 1 from sinking and making the connection between the anti-floating component and the device tighter and more secure.

[0040] The angle formed between the extension line of the outermost anti-floating member 6 and the center of the shield tunnel 1 is 90° to 150°; the anti-floating members are arranged in a fan shape, and the spacing distances between the upper and lower groups of anti-floating members are the same, so that the surrounding soil is reinforced and settlement is controlled.

[0041] The diameter of the grouting hole 8 is 2 cm to 4 cm, through which the grouting liquid can be injected into the device to complete the grouting operation.

[0042] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principle of the present invention. These improvements and substitutions should also be regarded as the protection scope of the present invention.

Claims

1. A shield tunnel anti-floating structure, comprising a shield tunnel (1), characterized in that: A grouting body (2) is arranged outside the shield tunnel (1), a cushion layer (3) is arranged outside the grouting body (2), and a plurality of cement soil piles (16) are formed by grouting outside the cushion layer (3); An embedded steel plate (7) is arranged inside the shield tunnel (1); A plurality of embedded anti-floating components (6) connected to the embedded steel plates (7) are protrudingly provided on the shield tunnel (1), and the anti-floating components (6) are sequentially penetrated inside the grouting body (2), the cushion layer (3) and the cement soil piles (16).

2. The shield tunnel anti-floating structure according to claim 1 is characterized in that: The curvature of the embedded steel plate (7) is consistent with that of the shield tunnel (1); The embedded steel plate (7) is provided with a mounting hole for penetrating the anti-floating component (6); The embedded steel plate (7) is fixedly connected to the shield tunnel (1).

3. The shield tunnel anti-floating structure according to claim 1 is characterized in that: The cement soil pile (16) comprises a vertical cement soil pile (4) and an inclined cement soil pile (5); the cement soil pile (16) is outside the cushion layer (3) and is connected to the cushion layer (3).

4. The shield tunnel anti-floating structure according to claim 3 is characterized in that: The diameter of the vertical cement soil pile (4) is 800 mm to 1500 mm; The diameter of the inclined cement soil pile (5) is 600 mm to 1200 mm.

5. The shield tunnel anti-floating structure according to claim 1 is characterized in that: A plurality of grouting holes (8) are provided in the shield tunnel (1); The grouting holes (8) are arranged in one-to-one correspondence with the embedded steel plates (7) and the anti-floating components (6).

6. The shield tunnel anti-floating structure according to claim 5 is characterized in that: The gap between the grouting hole (8) and the anti-floating component (6) is filled with a filler (9); A rubber ring (10) is provided between the upper end of the anti-floating component (6) and the shield tunnel (1).

7. The shield tunnel anti-floating structure according to claim 5, characterized in that: A plurality of grouting holes (8) are evenly and symmetrically distributed on the inner wall of the shield tunnel (1).

8. The shield tunnel anti-floating structure according to any one of claims 1 to 7, characterized in that: The thickness of the grouting body (2) is 100 mm to 150 mm.

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