Exploration drill hole sealing structure in shield tunnel

Abstract

The utility model relates to the technical field of shield tunnels, and discloses a hole sealing structure for an exploration drill hole in a shield tunnel, which comprises a flexible plug (1), a drill rod (2) for driving the flexible plug (1) to enter the drill hole, a shaft sleeve (3) sleeved on the drill rod (2) and a sealing cover (4) connected with the shaft sleeve (3), a fixed sleeve (5) is arranged at the top of the shaft sleeve (3), and a bolt tightening assembly (6) is arranged in the fixed sleeve (5). A sealing assembly (7) is arranged in the shaft sleeve (3); according to the hole sealing structure, the flexible plug is matched with the shaft sleeve, the sealing cover and the like, the flexible plug is placed at the preset position to be firmly combined with the hole wall, meanwhile, the sealing cover forms a sealing partition, the waterproof effect is improved, and water leakage and seepage accidents are reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of shield tunnels, in particular to a hole-sealing structure for exploration boreholes in shield tunnels. Background Art

[0002] As a commonly used machine in subway construction, the basic principle of a shield machine is to maintain the stability of the excavation face by applying a certain pressure. According to the different ways of applying pressure, it can be divided into slurry shield, earth pressure balance shield, etc., and the generally set pressure is above 2 bar. Before shield excavation, it is necessary to conduct a detailed exploration of the geology along its route. After the geological exploration, a cylindrical cavity will be formed at the drilling location. At present, the method of "backfilling with clay in the clay section and sand in the sandy soil layer" is mostly used, but the effect is often not good. Especially for exploration holes at the bottom of rivers and lakes, not only is the hole-sealing difficult, but also seepage is likely to occur after hole-sealing. If the route is adjusted later and the shield machine needs to pass through the drilling location, groundwater will flow into the shield section from the gaps in the filling materials of the drilling hole, flooding the tunnel and causing major safety accidents. The backfilling material should not be too hard. If concrete or the like is used for backfilling, it will hinder the shield machine and may even damage the shield machine. For this reason, some underwater exploration holes are selected far away from the subway excavation route, which will result in inaccurate exploration.

[0003] The prior art such as the underwater exploration hole hole-sealing process with the application number 201410391580.1 proposes a pile plug with a hook at the top, a conical head at the bottom, and a convex ring on the outer wall, and uses quick-setting cement slurry and the pile plug to cooperate to seal the underwater exploration hole. However, it consumes more cement slurry, the sealing structure is relatively single, the waterproof effect is poor, and leakage and water seepage accidents are likely to occur. Content of the Utility Model

[0004] Aiming at the deficiencies of the prior art, the purpose of the utility model is to provide a hole-sealing structure for exploration boreholes in shield tunnels. The hole-sealing structure uses a flexible plug in cooperation with a shaft sleeve, a sealing cover, etc. to place the flexible plug at a predetermined position to achieve a firm combination with the hole wall. At the same time, the sealing cover forms a sealing partition to improve the waterproof effect and reduce the occurrence of leakage and water seepage accidents.

[0005] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0006] A hole-sealing structure for exploration boreholes in shield tunnels includes a flexible plug, a drill rod for driving the flexible plug into the borehole, a shaft sleeve sleeved on the drill rod, and a sealing cover connected to the shaft sleeve. A fixed sleeve is provided at the top of the shaft sleeve, a tightening component is provided in the fixed sleeve, and a sealing component is provided in the shaft sleeve. When the flexible plug is lowered, the tightening component fixes the shaft sleeve and the sealing cover on the drill rod; after being lowered to the predetermined position, the drill rod drives the flexible plug to the sealing component, and the flexible plug is fixed by the sealing component to close the shaft sleeve.

[0007] Preferably, an activity groove is provided in the fixed sleeve. The fastening bolt assembly includes bolt rods located at both ends of the fixed sleeve and slidably disposed in the activity groove, a semi-circular sealing ring connected to the end of the bolt rod, and a spring sleeved on the bolt rod and abutting against the sealing ring. Under the elastic force of the spring, the two semi-circular sealing rings are driven to clamp the drill rod or the flexible plug.

[0008] Preferably, the sealing assembly includes positioning rings provided at both inner ends of the shaft sleeve and a plurality of groups of rubber rings provided between the two positioning rings. The plurality of groups of rubber rings are equally spaced, and a sealing airbag is provided between every two adjacent groups of rubber rings.

[0009] Preferably, the sealing airbag is a circular ring with a circular cross-section.

[0010] Preferably, the flexible plug includes a plug body. The plug body is cylindrical, and an annular protrusion is provided on its circumferential side. The annular protrusion matches the distance between every two adjacent groups of rubber rings or between adjacent rubber rings and the positioning ring.

[0011] Preferably, the flexible plug further includes a plug sleeve sleeved on the outer side of the plug body. A fixing groove cooperating with the plug sleeve is provided on the positioning ring located at the lower side, and the plug sleeve is connected to the fixing groove to further fix the flexible plug.

[0012] Preferably, a conical plug portion is provided at the bottom of the plug body.

[0013] Preferably, the sealing cover is hemispherical or conical.

[0014] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0015] The hole sealing structure of the present utility model uses a flexible plug in cooperation with a shaft sleeve, a sealing cover, etc. to realize that the flexible plug is placed at a predetermined position to achieve a firm combination with the hole wall. At the same time, the sealing cover forms a sealing partition, improving the waterproof effect and reducing the occurrence of water leakage and seepage accidents. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic structural diagram of the hole sealing structure of this exploration borehole in an unsealed state.

[0017] Figure 2 It is a schematic structural diagram of the hole sealing structure of this exploration borehole in a sealed state.

[0018] Figure 3 It is a schematic structural diagram of the hole sealing structure of this exploration borehole entering the exploration borehole.

[0019] Figure 4 It is a schematic structural diagram of fixing the flexible plug in the hole sealing structure of this exploration borehole.

[0020] Figure 5 This is a schematic structural diagram after the exploration borehole is sealed.

[0021] In the attached drawings: 1 - flexible plug, 11 - plug body, 111 - annular protrusion, 12 - plug sleeve, 13 - plug portion, 2 - drill pipe, 3 - bushing, 4 - seal cover, 5 - fixing sleeve, 51 - movable groove, 6 - tightening bolt assembly, 61 - bolt rod, 62 - sealing ring, 63 - spring, 7 - sealing assembly, 71 - positioning ring, 711 - fixing groove, 72 - rubber ring, 73 - sealing airbag. Specific implementation manners

[0022] Embodiment 1: A preferred embodiment of the present utility model provides a sealing structure for an exploration borehole in a shield tunnel, including a flexible plug 1, a drill pipe 2 for driving the flexible plug 1 into the borehole, a bushing 3 sleeved on the drill pipe 2, and a seal cover 4 connected to the bushing 3. The seal cover 4 is hemispherical or conical; a fixing sleeve 5 is provided at the top of the bushing 3, a tightening bolt assembly 6 is provided in the fixing sleeve 5, and a sealing assembly 7 is provided in the bushing 3. When the flexible plug 1 is lowered, the tightening bolt assembly 6 fixes the bushing 3 and the seal cover 4 on the drill pipe 2; after being lowered to a predetermined position, the drill pipe 2 drives the flexible plug 1 to the sealing assembly 7, and the flexible plug 1 is fixed by the sealing assembly 7 to seal the bushing 3; it uses the flexible plug 1 in cooperation with the bushing 3, the seal cover 4, etc. to place the flexible plug 1 at a predetermined position, achieve a firm bond with the hole wall, and at the same time the seal cover 4 forms a sealing partition to improve the waterproof effect and reduce the occurrence of water leakage and seepage accidents.

[0023] The flexible plug 1 includes a plug body 11. The plug body 11 is cylindrical, and an annular protrusion 111 is provided on its circumferential side. The annular protrusion 111 matches the distance between every two adjacent rubber rings 72 or between an adjacent rubber ring 72 and the positioning ring 71; the flexible plug 1 further includes a plug sleeve 12 sleeved on the outside of the plug body 11. A fixing groove 711 for cooperating with the plug sleeve 12 is provided on the lower positioning ring 71, and the plug sleeve 12 is connected to the fixing groove 711 to further fix the flexible plug 1; a conical plug portion 13 is provided at the bottom of the plug body 11. The plug body 11 and the plug portion 13 are made of natural rubber, which can effectively tighten with the hole wall.

[0024] Embodiment 2: A preferred embodiment of the present utility model provides a sealing structure for an exploration borehole in a shield tunnel. The difference from the above embodiment is only that: a movable groove 51 is provided in the fixing sleeve 5, and the tightening bolt assembly 6 includes bolt rods 61 located at both ends of the fixing sleeve 5 and slidably disposed in the movable groove 51, a semi-circular sealing ring 62 connected to the ends of the bolt rods 61, and a spring 63 sleeved on the bolt rods 61 and abutting against the sealing ring 62. The spring 63 drives the two semi-circular sealing rings 62 to clamp the drill pipe 2 or the flexible plug 1 under the elastic force.

[0025] Embodiment 3: A preferred embodiment of the present utility model provides a hole - sealing structure for exploration boreholes in a shield tunnel, and the difference from the above - mentioned embodiment is only that: the sealing assembly 7 includes positioning rings 71 provided at both inner ends of the bushing 3 and several groups of rubber rings 72 provided between the two positioning rings 71. The several groups of rubber rings 72 are equally spaced, and a sealing airbag 73 is provided between every two adjacent groups of rubber rings 72. The sealing airbag 73 is a circular - cross - sectioned ring.

[0026] A method for sealing exploration boreholes in a shield tunnel includes the following steps:

[0027] S1: Install a flexible plug 1 at the end of the drill pipe 2. Fix the bushing 3 and the sealing cover 4 on the drill pipe 2 through the fastening assembly 6. Under the action of the drilling rig, put the flexible plug 1 into the borehole to a predetermined position.

[0028] S2: After being lowered to the predetermined position, the drill pipe 2 drives the flexible plug 1 to the sealing assembly 7. The annular protrusion 111 on the circumferential side of the plug body 11 is clamped between the rubber rings 72 and the rubber rings 72 or the positioning ring 71. At the same time, the plug sleeve 12 is clamped into the fixing groove 711 to further fix the flexible plug 1.

[0029] S3: The drill pipe 2 continues to move upward under the action of the drilling rig. The spring 63 drives the two semi - circular sealing rings 62 to clamp the drill pipe 2 under the action of its elastic force. When the drill pipe 2 is separated from the fastening assembly 6, the spring 63 drives the two semi - circular sealing rings 62 to clamp the end of the flexible plug 1 under the action of its elastic force to seal the bushing 3.

[0030] S4: Put the grout - guiding pipe into the borehole above the bushing 3. Inject the prepared cement mortar into the borehole until it reaches the bedrock surface. Lift the grout - guiding pipe while injecting the mortar. After the grouting is completed, lift out the grout - guiding pipe and let the cement mortar solidify.

[0031] S5: Use a heavy - duty dynamic penetration test to check the quality of the mortar hole - sealing. After passing the test, seal the hole according to the principle of "returning soil for soil and sand for sand".

Claims

1. A hole-sealing structure for exploration boreholes in a shield tunnel, characterized in that It includes a flexible plug (1), a drill rod (2) for driving the flexible plug (1) into the drill hole, a bushing (3) sleeved on the drill rod (2), and a sealing cover (4) connected to the bushing (3). A fixing sleeve (5) is provided at the top of the bushing (3), a fastening component (6) is provided in the fixing sleeve (5), and a sealing component (7) is provided in the bushing (3). When the flexible plug (1) is lowered, the fastening component (6) fixes the bushing (3) and the sealing cover (4) on the drill rod (2). After being lowered to a predetermined position, the drill rod (2) drives the flexible plug (1) to the sealing component (7), and the flexible plug (1) is fixed by the sealing component (7) to close the bushing (3).

2. The plugging structure for exploration boreholes in a shield tunnel according to claim 1, characterized in that, An activity groove (51) is provided in the fixing sleeve (5). The fastening component (6) includes bolt rods (61) located at both ends of the fixing sleeve (5) and slidably arranged in the activity groove (51), a semi-circular sealing ring (62) connected to the end of the bolt rod (61), and a spring (63) sleeved on the bolt rod (61) and abutting against the sealing ring (62). Under the elastic force of the spring (63), the two semi-circular sealing rings (62) are driven to clamp the drill rod (2) or the flexible plug (1).

3. A plugging structure for exploration boreholes in a shield tunnel according to claim 1, characterized in that, The sealing component (7) includes positioning rings (71) provided at both inner ends of the bushing (3) and several groups of rubber rings (72) provided between the two positioning rings (71). The several groups of rubber rings (72) are equally spaced, and a sealing airbag (73) is provided between each adjacent two groups of rubber rings (72).

4. A plugging structure for exploration boreholes in a shield tunnel according to claim 3, characterized in that, The sealing airbag (73) is a circular ring with a circular cross-section.

5. A plugging structure for exploration boreholes in a shield tunnel according to claim 3 or 4, characterized in that, The flexible plug (1) includes a plug body (11). The plug body (11) is cylindrical, and an annular protrusion (111) is provided on its circumferential side. The annular protrusion (111) matches the distance between each adjacent two groups of rubber rings (72) or between the adjacent rubber ring (72) and the positioning ring (71).

6. The plugging structure for exploration boreholes in a shield tunnel according to claim 5, characterized in that, The flexible plug (1) further includes a plug sleeve (12) sleeved on the outside of the plug body (11). A fixing groove (711) cooperating with the plug sleeve (12) is provided on the lower positioning ring (71). The plug sleeve (12) is connected to the fixing groove (711) to further fix the flexible plug (1).

7. A plugging structure for exploration boreholes in a shield tunnel according to claim 6, characterized in that, A conical plug part (13) is provided at the bottom of the plug body (11).

8. A plugging structure for exploration boreholes in a shield tunnel according to claim 1, characterized in that, The sealing cover (4) is hemispherical or conical.

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