A device for controlling the floating of a segment of an overfall tunnel

Abstract

The present application relates to tunnel anti-floating technical field, specifically disclose a kind of superimposed tunnel segment floating control device, including being arranged in geological layer upper and lower superimposed arrangement lower tunnel and upper tunnel, upper tunnel is equipped with multiple groups of partition device, each group of partition device is sequentially arranged along the axis direction of upper tunnel, upper tunnel is equipped with corresponding chute of partition device, partition device is slidably connected in chute, reinforcement pipe is arranged downward from each partition device, another end of reinforcement pipe is inserted into lower tunnel and passes through from the accommodation hole of arc plate, arc plate is fixed to the top of lower tunnel inner side.The beneficial effects of the present application are: by the continuous axial partition plate formed by unfolding multiple groups of partition device, the space outside the upper tunnel segment is divided into multiple independent grouting areas, regional and batch grouting are realized, the total floating force generated by single grouting slurry on the segment is reduced, and the segment floating induced misalignment and damage are effectively prevented.

Description

Technical Field

[0001] This invention relates to the field of tunnel anti-buoyancy technology, and in particular to a device for controlling the buoyancy of stacked tunnel segments. Background Technology

[0002] Stacked tunnels are tunnels arranged in intersecting vertical spaces (e.g., perpendicular axial direction). With the increasing density of urban underground transportation networks, stacked tunnels are becoming more common. In such projects, the lower tunnel is typically constructed and lined first, followed by the upper tunnel. After the upper tunnel segments are assembled, the gaps behind them need to be grouted to control ground settlement, improve waterproofing, and enhance overall stability.

[0003] In conventional full-section or long-distance continuous grouting operations, the grouting pressure and grout buoyancy can easily cause the upper tunnel segments to float locally or as a whole, which can lead to segment misalignment, damage, bolt breakage, or even water inrush accidents, seriously threatening structural safety.

[0004] However, in the special case of stacked tunnels, the completed lower tunnel significantly exacerbates the aforementioned risk of uplift. Specifically, after the lower tunnel is excavated, the original strata beneath the upper tunnel are removed and replaced by the tunnel structure and backfill, resulting in a significantly lower overall stiffness and lateral restraint compared to the original strata. This causes the bottom of the upper tunnel segments to lose the support and anchorage of continuous strata, drastically reducing the upper tunnel's resistance to deformation under upward grout pressure. Simultaneously, because the lower tunnel occupies the space below, the grout, under pressure, cannot effectively dissipate downwards towards the lower tunnel as it spreads along the outer wall of the segments. A large amount of grout is forced to flow and accumulate in the weakest restraint area—the bottom and lower sides of the upper tunnel—resulting in a large-area superposition of buoyancy and increasing the overall upward tendency of the tunnel segments.

[0005] Existing anti-buoyancy measures typically involve using anchor bolts to constrain the segments. However, during the construction of stacked tunnels, this anti-buoyancy measure cannot prevent grout from flowing through the tunnel. The grout will still be forced to accumulate at the bottom of the upper tunnel, which can easily cause the segments of the upper tunnel to float. Summary of the Invention

[0006] The purpose of this invention is to address the shortcomings of existing technologies by proposing a floating control device for stacked tunnel segments.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: A floating control device for stacked tunnel segments includes a lower tunnel and an upper tunnel stacked vertically within a geological layer. The lower and upper tunnels are axially perpendicular. The upper tunnel has multiple sets of partition devices, each set arranged sequentially along the axial direction of the upper tunnel. The upper tunnel has grooves corresponding to the partition devices, and the partition devices are slidably connected within the grooves. A reinforcing pipe is installed downward from each partition device, with the other end of each reinforcing pipe extending into the lower tunnel and passing through a clearance hole in an arc-shaped plate. The arc-shaped plate is fixed to the top of the inner side of the lower tunnel. Pulling the reinforcing pipe downward from the lower tunnel causes the partition device to protrude to the outer side of the upper tunnel. Each set of partition devices is combined to form a partition plate, and an independent grouting area is formed between two adjacent partition plates.

[0008] Preferably, the partition device includes a housing, a cover plate is detachably connected to one side of the housing, and a first guide groove is provided on both sides of the housing. An extension plate is slidably connected in each first guide groove. Two adjacent extension plates of the same set of partition devices extend outward and contact each other.

[0009] Preferably, a second guide groove is provided on both sides of the box body, a guide rod is slidably connected in each second guide groove, a slider is fixedly connected to one end of each guide rod, a spring is fixedly connected between the slider and the inner wall of the box body, a push rod is fixedly connected to one side of each slider, and the other end of each push rod passes through the clearance hole of another slider and abuts against the extension plate.

[0010] Preferably, each slider has a crossbeam hinged to one side, and the other end of each crossbeam is hinged to a collar. The collar has a ball hinged to a sphere, and the sphere has a mounting hole. The reinforcing tube is fixed in the mounting hole.

[0011] Preferably, the cover plate is provided with a feeding pipe.

[0012] The beneficial effects of this invention are as follows: by unfolding multiple sets of partition devices to form a continuous axial partition plate, the space outside the upper tunnel segment is divided into multiple independent grouting areas, realizing grouting in different areas and batches, reducing the total buoyancy force of a single grouting slurry on the segment, effectively preventing misalignment and damage caused by segment floating, and at the same time, using multiple reinforcing pipes to pull from the inside of the lower tunnel, always applying a stable downward pulling force to the upper tunnel, providing anti-buoyancy force to the upper tunnel. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the basic structure of the present invention; Figure 2 This is a schematic diagram of the connection structure between the partition device and the upper tunnel; Figure 3 This is a schematic diagram of the basic structure of the partition device; Figure 4 yes Figure 3 Enlarged view of part A; Figure 5 This is a schematic diagram of the connection structure between the upper tunnel and the partition device. Detailed Implementation

[0014] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0015] like Figures 1-5 As shown in the figure, this embodiment provides a floating control device for stacked tunnel segments, including a lower tunnel 200 and an upper tunnel 300 stacked vertically within a geological layer 100, with the lower tunnel 200 and the upper tunnel 300 axially perpendicular. The lower tunnel 200 has already completed its lining construction, while the upper tunnel 300 is constructed subsequently.

[0016] Multiple sets of partition devices 1 are installed on the upper tunnel 300. Each set of partition devices 1 is arranged sequentially along the axial direction of the upper tunnel 300. The upper tunnel 300 has a sliding groove corresponding to the partition device 1. The partition device 1 is slidably connected in the sliding groove, so that the partition device 1 can slide inward and outward along the radial direction of the upper tunnel 300. In the initial state, the partition device 1 is completely housed in the sliding groove to avoid the partition device 1 interfering with the segment assembly and initial grouting.

[0017] A reinforcing pipe 2 is installed downwards from each partition device 1. The reinforcing pipe 2 has multiple grout outlets on its wall. The lower end of each reinforcing pipe 2 extends into the lower tunnel 200 and passes through the clearance hole of the arc-shaped plate 4. The arc-shaped plate 4 is fixed to the top inner side of the lower tunnel 200. Pulling the reinforcing pipe 2 downwards from inside the lower tunnel 200 causes the partition device 1 to protrude to the outside of the upper tunnel 300. Each set of partition devices 1 forms a partition plate, and independent grouting areas are formed between adjacent partition plates. The lower end of the reinforcing pipe 2 has an external thread section, where a locking nut is threadedly connected. The locking nut secures the reinforcing pipe 2 to the arc-shaped plate 4.

[0018] When it is necessary to control buoyancy and perform regional grouting, construction workers can use electric or hydraulic tools to pull the reinforcing pipe 2 downwards within the lower tunnel 200. The reinforcing pipe 2 drives the entire partition device 1 to move radially outwards along the chute, so that each group of partition devices 1 extends from the outer wall of the upper tunnel 300 segments, forming a partition unit body arranged axially within the same group. Through subsequent deployment, the gaps between adjacent partition devices 1 within the same group are closed, thus forming a continuous axial partition plate. In this way, the outer wall of the upper tunnel 300 segments and the geological layer 100 are divided into multiple independent grouting areas. Grouting can be performed sequentially or in batches in each independent area, and the grout is strictly confined to a single area, preventing it from flowing into adjacent areas. This significantly reduces the amount of grout required for a single grouting session and effectively avoids buoyancy superposition caused by traditional processes. Meanwhile, the multiple reinforcing pipes 2 that are pulled down and locked are always in a tensioned state, and are pressed onto the arc plate 4 by locking nuts, which exert a continuous downward pulling force on the upper tunnel 300, directly and in real time resisting the upward floating trend of the tunnel segments.

[0019] In this embodiment, the partition device 1 includes a housing 11, with a cover plate 12 detachably connected to one side of the housing 11. The detachable nature is existing technology and will not be described further. The cover plate 12 is removed only when the reinforcing pipe 2 is installed, and is reinstalled after the reinforcing pipe 2 is installed. Both sides of the housing 11 are provided with first guide grooves 111, and each first guide groove 111 is slidably connected to an extension plate 3. In the non-working state, the extension plate 3 retracts into the housing 11. In the working state, the extension plates 3 of two adjacent partition devices 1 in the same group extend outwards and make tight contact, thereby sealing the gap between the partition devices 1.

[0020] Both sides of the housing 11 are provided with second guide grooves 112. Each second guide groove 112 is slidably connected to a guide rod 14. One end of each guide rod 14 is fixedly connected to a slider 15. A spring 16 is fixedly connected between the slider 15 and the housing 11. A push rod 31 is fixedly connected to one side of each slider 15. The other end of each push rod 31 passes through the clearance hole of another slider 15 and is in close contact with the extension plate 3. A crossbeam 17 is hinged to one side of each slider 15. The other end of each crossbeam 17 is hinged to the same collar 18. A ball 19 is ball-hinged inside the collar 18. The ball 19 has a mounting hole, and the reinforcing tube 2 is fixed in the mounting hole. The purpose of using a ball hinge is to allow the reinforcing tube 2 to deflect within a certain angle range. A feeding pipe 13 is provided on the cover plate 12. The feeding pipe 13 can be connected to external grouting equipment and ceramic ball feeding equipment. During operation, when the reinforcing pipe 2 is pulled downwards, the ball 19 and the collar 18 move downwards, causing the two crossbeams 17 to rotate from an inclined state to a horizontal direction. As the crossbeams 17 rotate, they push the sliders 15 on both sides to overcome the resistance of the spring 16 and move closer together. They also push the extension plate 3 outwards through the push rod 31 until it is tightly fitted with the extension plate 3 of the adjacent partition device. To ensure a tight seal, water-swellable rubber strips can be pre-attached to the contact surfaces of the extension plates 3. Simultaneously, the crossbeams 17 compress the geological layer 100, compacting the soil and forming a groove.

[0021] After the groove is formed, ceramic balls are added into the inner cavity of the box 11 and the groove through the feeding pipe 13 until the groove and the inside of the box 11 are completely filled. The ceramic balls act as a skeleton, increasing the volume stability of the subsequent grout. Then, cement-based grout is injected simultaneously into the feeding pipe 13 and the reinforcing pipe 2. The grout fills the box 11 and the groove, firmly bonding the isolation device 1 to the surrounding strata. The grout formed is similar to an axially stiffening long beam added to the outer wall of the tunnel segment, significantly increasing the contact area between the upper tunnel and the geological layer. The grout outlet on the reinforcing pipe 2 also allows the grout to penetrate into the geological layer, supplementing and reinforcing the geological layer and further improving the overall anchoring effect.

[0022] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A floating control device for stacked tunnel segments, characterized in that: The system includes a lower tunnel (200) and an upper tunnel (300) stacked vertically within a geological layer (100). The lower tunnel (200) and the upper tunnel (300) are axially perpendicular. The upper tunnel (300) is equipped with multiple sets of partition devices (1), each set of partition devices (1) arranged sequentially along the axial direction of the upper tunnel (300). The upper tunnel (300) is equipped with a groove corresponding to the partition device (1), and the partition device (1) is slidably connected within the groove. A reinforcing pipe (2) is installed downward on the partition device (1). The other end of the reinforcing pipe (2) extends into the lower tunnel (200) and passes through the clearance hole of the arc plate (4). The arc plate (4) is fixed to the top of the inner side of the lower tunnel (200). The reinforcing pipe (2) is pulled downward from the lower tunnel (200) so that the partition device (1) protrudes to the outside of the upper tunnel (300). Each set of partition devices (1) is combined to form a partition plate. An independent grouting area is formed between two adjacent partition plates. The partition device (1) includes a box (11), a cover plate (12) is detachably connected to one side of the box (11), and a first guide groove (111) is provided on both sides of the box (11). An extension plate (3) is slidably connected in each of the first guide grooves (111). Two adjacent extension plates (3) of the same partition device (1) extend outward and contact each other.

2. The stacked tunnel segment floating control device according to claim 1, characterized in that: The box (11) is provided with a second guide groove (112) on both sides. A guide rod (14) is slidably connected in each second guide groove (112). A slider (15) is fixedly connected to one end of each guide rod (14). A spring (16) is fixedly connected between the slider (15) and the inner wall of the box (11). A push rod (31) is fixedly connected to one side of each slider (15). The other end of each push rod (31) passes through the clearance hole of another slider (15) and abuts against the extension plate (3).

3. The stacked tunnel segment floating control device according to claim 2, characterized in that: Each slider (15) is hinged to a crossbeam (17) on one side, and the other end of each crossbeam (17) is hinged to a collar (18). The collar (18) is hinged to a ball (19), and the ball (19) has a mounting hole. The reinforcing tube (2) is fixed in the mounting hole.

4. The stacked tunnel segment floating control device according to claim 3, characterized in that: The cover plate (12) is provided with a feeding pipe (13).

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