Tunnel dissolved cavity plugging structure

Abstract

The utility model relates to the technical field of tunnel construction, and provides a tunnel dissolved cavity blocking structure which comprises a first inverted arch prefabricated part and second inverted arch prefabricated parts symmetrically arranged on the two sides of the first inverted arch prefabricated part. The inverted arch is additionally arranged in the tunnel spanning cavern area, so that the bottom of the tunnel and the top of the cavern can form an integral reinforced concrete structure, stress is dispersed, a cavern backfill area is prevented from sinking and cracking, and the inverted arch structure has the advantages of being high in safety and practicability, low in construction cost and short in construction period. The inverted arch is formed by splicing the first inverted arch prefabricated part and the second inverted arch prefabricated part through the splicing assembly, the site construction time can be greatly shortened, the construction period can be shortened, the engineering cost can be reduced, and more flexibility can be brought to tunnel engineering; the sealing assembly is arranged between the first inverted arch prefabricated part and the second inverted arch prefabricated part, so that the connection firmness and the connection sealing performance of the first inverted arch prefabricated part and the second inverted arch prefabricated part can be improved after installation.

Description

Technical Field

[0001] This utility model relates to the field of tunnel construction technology, specifically to a tunnel cavity sealing structure. Background Technology

[0002] Currently, there are two common methods for dealing with tunnels crossing karst cavities. One is to fill the karst cavity with concrete. This method involves directly pouring concrete into the cavity to fill it completely, using the filled concrete to provide load-bearing capacity and ensure that vehicles can cross the cavity. The other method is to build a bridge to cross the cavity. This method involves constructing piers inside the cavity and then erecting T-beams or casting-in-place bridges to cross it.

[0003] While concrete filling can fill and cross karst cavities using the methods described above, it requires a large volume of concrete for large cavities, resulting in high construction costs. Furthermore, the concrete filling blocks the seepage channels for groundwater, causing groundwater to accumulate and raising the water table. This increased water pressure poses a safety hazard to the tunnel invert. While bridge construction can effectively cross karst cavities and provide a channel for groundwater, it is costly and time-consuming, significantly increasing construction costs. Therefore, a tunnel karst cavity sealing structure is needed. Utility Model Content

[0004] To address the shortcomings of existing technologies, this utility model provides a tunnel cavity sealing structure, solving the technical problems mentioned in the background section.

[0005] The technical solution of this utility model is as follows: a tunnel cavity sealing structure, including a first invert precast component and second invert precast components symmetrically arranged on both sides of the first invert precast component. Each of the two second invert precast components is provided with multiple vertically extending steel bar joints at the end away from the first invert precast component. The side of the first invert precast component is provided with an assembly component for connecting the second invert precast components to form a complete invert.

[0006] The assembly component includes a positioning groove on the side of the second invert precast component, a positioning plate fixedly connected to the side of the first invert precast component, a bolt on the side of the positioning plate, a threaded hole on the inner wall of the positioning groove, and a power component for retracting the bolt into the positioning plate and threading the bolt into the threaded hole on the side of the positioning plate away from the bolt.

[0007] Preferably, the power assembly includes a rotating rod, a long rod is fixedly connected to the end face of the rotating rod, a shrinking cylinder is fixedly connected to the end of the long rod away from the rotating rod and rotatably connected to the inner wall of the positioning plate, a bolt is slidably sleeved inside the shrinking cylinder, and a nut is fixedly connected to the inner wall of the positioning plate and threadedly connected to the bolt.

[0008] Preferably, the inner wall of the shrink tube is provided with a horizontal groove, and a slider is fixedly connected to the outer wall of the bolt, the slider sliding left and right along the length of the groove.

[0009] Preferably, an annular plate is fixedly connected to the outer wall of the long rod, and a torsion spring is fixedly connected to the side of the annular plate. The end of the torsion spring away from the annular plate is fixedly connected to the positioning plate.

[0010] Preferably, the side of the first invert precast component is provided with a sealing component for sealing the gap at the joint between the first invert precast component and the second invert precast component. The sealing component includes a sealing ring fixed to the side of the first invert precast component, and a sealing groove adapted to the sealing ring is opened on the side of the second invert precast component.

[0011] Preferably, a columnar groove is provided on the side of the first invert arch precast component, and a limiting plate is slidably sleeved inside the columnar groove. A push plate and an airbag are fixedly connected to both sides of the limiting plate, and the end of the airbag away from the limiting plate is fixedly connected to the inner wall of the columnar groove.

[0012] Preferably, a semi-circular pipe is fixedly connected to the inner wall of the first invert arch precast component, and the two ends of the semi-circular pipe are fixedly connected to the airbag and the sealing ring, respectively.

[0013] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0014] 1. This utility model adds an inverted arch to the tunnel crossing the karst cavity area, which can form an integral reinforced concrete structure at the bottom of the tunnel and the top of the karst cavity, thereby dispersing the stress and preventing the karst cavity backfill area from sinking and cracking. It has the advantages of high safety, strong practicality, low project cost and short construction period.

[0015] 2. This utility model sets the invert arch as a first invert arch prefabricated component and a second invert arch prefabricated component assembled by assembly components, which can greatly reduce on-site construction time, shorten the construction period, reduce project costs, and bring more flexibility to tunnel engineering.

[0016] 3. The present invention designs a sealing component, which, by placing the sealing component between the first invert precast component and the second invert precast component, can improve the firmness and sealing performance of the connection between the two components after installation. Attached Figure Description

[0017] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0018] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0019] Figure 2 This is an exploded structural diagram of the present invention;

[0020] Figure 3 The present utility model proposes Figure 2 Side view and enlarged structural schematic diagram;

[0021] Figure 4 This is a cross-sectional view and a partially enlarged schematic diagram of the positioning plate proposed in this utility model;

[0022] Figure 5 This is a schematic diagram of the threaded hole structure proposed in this utility model;

[0023] Figure 6 This is a schematic diagram of the push plate structure proposed in this utility model.

[0024] In the diagram: 1. First invert arch precast component; 2. Second invert arch precast component; 3. Rebar joint; 4. Assembly component; 41. Positioning groove; 42. Positioning plate; 43. Bolt; 44. Power component; 441. Rotary rod; 442. Long rod; 443. Ring plate; 444. Contraction cylinder; 445. Torsion spring; 446. Nut; 45. Threaded hole; 5. Sealing component; 51. Sealing ring; 52. Sealing groove; 53. Push plate; 54. Limiting plate; 55. Airbag; 56. Semi-ring pipe. Detailed Implementation

[0025] The technical solutions of this utility model will be clearly and completely described below with reference to the embodiments of this utility model. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this utility model.

[0026] Karst is highly developed in the mountainous areas of Southwest China. Therefore, large karst cavities are often encountered during the construction of tunnel projects such as highway tunnels and railway tunnels. In particular, large karst cavities with thin roofs at the bottom of tunnels are often encountered. Due to their thin roofs and low load-bearing capacity, if these types of karst cavities are not effectively treated, they will pose a safety hazard of collapse during the construction and operation periods.

[0027] While existing methods using concrete filling can fill and cross cavities, for large cavities, the large volume of concrete required results in high construction costs. Furthermore, the concrete filling blocks subsequent groundwater seepage channels, causing groundwater to accumulate, raising the water table, and increasing water pressure, which poses a safety hazard to the tunnel invert. While bridge construction can effectively cross cavities and provide a channel for groundwater, it is also costly and time-consuming, significantly increasing construction costs. Please refer to [link / reference]. Figures 1-6A tunnel cavity sealing structure is provided, including a first invert precast component 1 and second invert precast components 2 symmetrically arranged on both sides of the first invert precast component 1. Each of the two second invert precast components 2 has multiple vertically extending steel bar joints 3 at the end away from the first invert precast component 1.

[0028] refer to Figures 2-5 As shown, while concrete filling in existing methods can fill karst cavities, it requires a large volume of concrete for large cavities, resulting in high construction costs. Furthermore, the concrete filling blocks the seepage channels for groundwater, causing groundwater to accumulate and raising the water table, leading to increased water pressure and potential safety hazards to the tunnel invert. While bridge construction can effectively cross karst cavities and provide a channel for groundwater, it is costly and time-consuming, significantly increasing construction costs. To provide a method that is safe, practical, cost-effective, and has a short construction period, the following steps are taken: First, after determining the extent of the karst cavity crossed by the tunnel through preliminary exploration, the top rock mass of the karst cavity below is blasted at the bottom of the invert within this area, forming a backfilling shaft approximately 8m long and 6m wide.

[0029] The second step is for the excavator to go down into the working shaft to excavate and backfill the cavity area with slag and stone. When the bottom cavity area within the tunnel is completely backfilled to the bottom of the original cavity top plate, five steel pipes with a diameter of 50cm are buried through the tunnel for later drainage of groundwater.

[0030] The third step is to backfill the original cavity top plate area of ​​the working shaft with C15 rubble concrete.

[0031] The fourth step is to add an invert arch to the tunnel crossing the karst cavity area, with an overlap length of not less than 3m at both ends, so that the bottom of the tunnel and the top of the karst cavity form a reinforced concrete structure as a whole, distributing the stress and preventing the karst cavity backfill area from settling and cracking. Traditional tunnel invert arch structure construction adopts on-site operation, that is, manual binding of steel bars and formwork and on-site pouring of concrete, which takes a long time. In order to reduce the on-site construction time and shorten the construction period, the following settings are made: the side of the first invert arch precast component 1 is provided with an assembly component 4 for connecting the second invert arch precast component 2 to form a complete invert arch. The assembly component 4 includes a positioning groove 41 opened on the side of the second invert arch precast component 2. A positioning plate 42 is fixedly connected to the side of the first invert arch precast component 1. Bolts 43 are provided on the side of the positioning plate 42. Threaded holes 45 are opened on the inner side wall of the positioning groove 41. The side of the positioning plate 42 away from the bolts 43 is provided with A power assembly 44 is provided to retract the bolt 43 into the positioning plate 42 and thread the bolt 43 into the threaded hole 45. The power assembly 44 includes a rotating rod 441, a long rod 442 is fixedly connected to the end face of the rotating rod 441, and a shrinking cylinder 444 that is rotatably connected to the inner wall of the positioning plate 42 is fixedly connected to the end of the long rod 442 away from the rotating rod 441. The bolt 43 is slidably sleeved inside the shrinking cylinder 444. A groove is transversely opened on the inner wall of the shrinking cylinder 444. A slider is fixedly connected to the outer wall of the bolt 43. The slider slides left and right along the length of the groove. A nut 446 that is threadedly connected to the bolt 43 is fixedly connected to the inner wall of the positioning plate 42. An annular plate 443 is fixedly connected to the outer wall of the long rod 442. A torsion spring 445 is fixedly connected to the side of the annular plate 443. The end of the torsion spring 445 away from the annular plate 443 is fixedly connected to the positioning plate 42. Before splicing, rotate the swivel rod 441 to make the long rod 442 drive the shrinking cylinder 444 to rotate and twist the torsion spring 445. The rotation of the shrinking cylinder 444 causes the bolt 43 to rotate synchronously through the slider in the groove and be threaded to the nut 446 and rotate back into the positioning plate 42. At this time, align the positioning plate 42 with the positioning groove 41 and insert it. When the bolt 43 is opposite to the threaded hole 45, the torsion spring 445 drives the long rod 442 to reset and rotate, so that the bolt 43 rotates and is inserted into the threaded hole 45 to complete the installation. Since the invert arch is used in the tunnel as part of the tunnel support structure, it can be known that the invert arch in the tunnel design is permanent and does not need to be disassembled. The above operation can reduce the amount of on-site processing and improve the installation efficiency.

[0032] refer to Figures 2-6As shown, the invert arch, as the supporting structure of the tunnel, plays a crucial role in bearing loads and resisting forces due to its overall continuity and integrity. Gaps between the first invert arch precast component 1 and the second invert arch precast component 2 can lead to a decrease in the overall strength and stability of the structure, increasing the risk of structural instability. To improve the firmness of the spliced ​​joint between the first invert arch precast component 1 and the second invert arch precast component 2, the following design is implemented: a sealing component 5 is provided on the side of the first invert arch precast component 1 to seal the gap at the joint between the first invert arch precast component 1 and the second invert arch precast component 2. The sealing component 5 includes a fixing... A sealing ring 51 is provided on the side of the first invert precast component 1, and a sealing groove 52 adapted to the sealing ring 51 is provided on the side of the second invert precast component 2. A columnar groove is provided on the side of the first invert precast component 1, and a limiting plate 54 is slidably sleeved inside the columnar groove. A push plate 53 and an airbag 55 are fixedly connected to both sides of the limiting plate 54, respectively. One end of the airbag 55 away from the limiting plate 54 is fixedly connected to the inner wall of the columnar groove. A semi-ring pipe 56 is fixedly connected to the inner wall of the first invert precast component 1, and the two ends of the semi-ring pipe 56 are fixedly connected to the airbag 55 and the sealing ring 51, respectively. As the positioning plate 42 is fully inserted into the positioning groove 41, it will push the push plate 53 back into the first invert arch precast component 1. The retraction of the push plate 53 will cause the limiting plate 54 to squeeze the airbag 55, so that the gas in the airbag 55 can be transmitted into the sealing ring 51 through the semi-ring pipe 56. When the sealing ring 51 is engaged with the sealing groove 52, the expansion of the sealing ring 51 can enhance the sealing effect and further reduce the gap at the joint between the first invert arch precast component 1 and the second invert arch precast component 2.

[0033] The above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A tunnel cavity sealing structure, comprising a first invert precast component (1) and two second invert precast components (2) symmetrically arranged on both sides of the first invert precast component (1), wherein each of the two second invert precast components (2) is provided with multiple vertically extending steel bar joints (3) at the end away from the first invert precast component (1), characterized in that, The side of the first invert precast component (1) is provided with an assembly component (4) for connecting the second invert precast component (2) to form a complete invert arch; The assembly component (4) includes a positioning groove (41) on the side of the second invert precast component (2), a positioning plate (42) is fixedly connected to the side of the first invert precast component (1), a bolt (43) is provided on the side of the positioning plate (42), a threaded hole (45) is provided on the inner wall of the positioning groove (41), and a power component (44) is provided on the side of the positioning plate (42) away from the bolt (43) to retract the bolt (43) into the positioning plate (42) and thread the bolt (43) into the threaded hole (45).

2. The tunnel cavity sealing structure according to claim 1, characterized in that, The power assembly (44) includes a swivel rod (441), a long rod (442) is fixedly connected to the end face of the swivel rod (441), a shrink cylinder (444) is fixedly connected to the end of the long rod (442) away from the swivel rod (441) and is rotatably connected to the inner wall of the positioning plate (42), a bolt (43) is slidably sleeved inside the shrink cylinder (444), and a nut (446) is fixedly connected to the inner wall of the positioning plate (42) and is threadedly connected to the bolt (43).

3. The tunnel cavity sealing structure according to claim 2, characterized in that, The inner wall of the shrink tube (444) is provided with a horizontal groove, and the outer wall of the bolt (43) is fixedly connected with a slider, which slides left and right along the length of the groove.

4. The tunnel cavity sealing structure according to claim 2, characterized in that, An annular plate (443) is fixedly connected to the outer wall of the long rod (442), and a torsion spring (445) is fixedly connected to the side of the annular plate (443). The end of the torsion spring (445) away from the annular plate (443) is fixedly connected to the positioning plate (42).

5. The tunnel cavity sealing structure according to claim 1, characterized in that, The side of the first invert precast component (1) is provided with a sealing component (5) for sealing the gap at the joint between the first invert precast component (1) and the second invert precast component (2). The sealing component (5) includes a sealing ring (51) fixed on the side of the first invert precast component (1) and a sealing groove (52) adapted to the sealing ring (51) on the side of the second invert precast component (2).

6. The tunnel cavity sealing structure according to claim 1, characterized in that, The first inverted arch precast component (1) has a columnar groove on its side. A limiting plate (54) is slidably fitted inside the columnar groove. A push plate (53) and an airbag (55) are fixedly connected to both sides of the limiting plate (54). One end of the airbag (55) away from the limiting plate (54) is fixedly connected to the inner wall of the columnar groove.

7. The tunnel cavity sealing structure according to claim 1, characterized in that, The inner wall of the first invert arch precast component (1) is fixedly connected with a semi-circular pipe (56), and the two ends of the semi-circular pipe (56) are fixedly connected to the airbag (55) and the sealing ring (51) respectively.

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