Comprehensive treatment structure for tunnel passing through large karst cave

Abstract

The utility model relates to a comprehensive treatment structure for a tunnel to pass through a large karst cave, clay in the karst cave is dug below the bottom of the tunnel, a bearing platform is arranged below the tunnel in the karst cave, a steel pipe pile is arranged at the bottom of the bearing platform towards the clay, a drainage system comprises a reserved drainage pipe and a water collecting tank, foam concrete is poured above the clay, and the water collecting tank is arranged below the bearing platform. And a grouting position monitor and a water collecting tank are arranged at the pouring elevation position of the foam concrete. The device has the beneficial effects that the hoisting machinery is used as a segmental splicing and lowering device for the steel pipe pile and the reinforcement cage, the clamping hand is detachably mounted on the outer side of the sliding plate as required, and the switching between the clamping and lowering construction of the steel pipe pile and the reinforcement cage can be realized by modifying the hoisting machinery and replacing the clamping hand; the problem that low clearance construction in the tunnel is limited is well solved; a plurality of drainage pipes and water collecting tanks are reserved in the karst cave, a karst cave reserved drainage system is formed, drainage smoothness in the tunnel is achieved, and the pressure of a tunnel haunch is effectively reduced.

Description

Technical Field

[0001] The utility model relates to the field of highway tunnel construction, in particular to a comprehensive treatment structure for a tunnel passing through a large karst cave. Background Art

[0002] Karst is a general term for various surface or underground dissolution phenomena formed by the chemical and mechanical destruction of soluble rock layers by surface water and groundwater. The distribution area of soluble rocks in my country is about 3.65×106km 2 , accounting for 1 / 3 of the country's land area, is one of the countries with the most developed karst in the world. There is great resistance to the construction of tunnel projects in karst areas. The karst cave is located at the bottom, and because the filling is soft and loose, it is not conducive to the construction of the tunnel base; it is located at the top, and the filling is prone to collapse during construction, so it is not suitable for excavation; the karst caves in some areas are not solid, and there are many broken materials. If you are not careful during construction, it is easy to collapse; when encountering a filling capsule filled with water, when the tunnel is excavated to its edge, the water-containing filling continues to flow into the tunnel, which is difficult to stop, and even the surface cracks and sinks, and the mountain pressure increases dramatically. During construction, it is also possible to encounter large water capsules, causing rocks and soil to rush into the tunnel with water; some karst caves are complex, circuitous, and widely distributed, which are difficult to handle.

[0003] Especially for large caves, it is impossible to backfill them completely. It is necessary to design and formulate the treatment structure of the tunnel cave in advance to avoid construction accidents. Utility Model Content

[0004] The utility model aims to overcome the deficiencies in the prior art and provide a comprehensive treatment structure for a tunnel passing through a large karst cave.

[0005] This type of tunnel passes through a large karst cave comprehensive treatment structure, including: cap, hoisting machinery, drainage system, grouting position monitor, foam concrete, invert, secondary lining and initial tunnel support;

[0006] The clay in the cave is dug to the bottom of the tunnel. A cap is provided below the tunnel in the cave. Steel pipe piles are driven into the clay from the bottom of the cap. The drainage system includes a reserved drainage pipe and a water collection tank. Foam concrete is poured above the clay. A grouting position monitor and a water collection tank are provided at the pouring elevation of the foam concrete. One end of the reserved drainage pipe is inserted into the water collection tank, and the other end extends to the drainage ditch in the tunnel.

[0007] Preferably, the hoisting machine includes a hydraulic telescopic rod, a sliding plate, a clamping hand, adjustable counterweights, a rotating shaft, a support rod, and crawlers. The clamping hand is detachably installed outside the sliding plate. The clamping hand includes a movable clamping hand and a fixed clamping hand, and is used for clamping the steel pipe piles and the steel reinforcement cages of the pile caps. The fixed clamping hand is fixed at the bottom of the sliding plate, and the movable clamping hand moves up and down along the sliding plate above the fixed clamping hand.

[0008] Preferably, when the clamping hand is a clamping hand for clamping steel pipe piles, both the movable clamping hand and the fixed clamping hand are provided with steel pipe pile hoops; when the clamping hand is a clamping hand for clamping steel reinforcement cages, the movable clamping hand and the fixed clamping hand are provided with double-layer forks.

[0009] Preferably, anchor bolts are driven into the rock walls on both sides of the unfilled part of the karst cave, and an adjustable strut is installed between the ends of the anchor bolts on the rock walls on both sides; the ends of the anchor bolts are anchored to the rock walls with backing plates and nuts, and the two ends of the adjustable strut are concave and clamped with the ends of the anchor bolts; the rock walls are sprayed with concrete.

[0010] Preferably, the grouting position monitor includes a conductive part, an insulating part, a hollow part, and a pressure sensor. The grouting position monitor is tubular, and the tube wall is obtained by splicing the conductive part and the insulating part in pairs. The pressure sensor is arranged on the insulating part on the top surface of the grouting position monitor. The height of the top surface of the grouting position monitor is the same as the height of the top surface of the sump. The grouting position monitor is connected to a receiving instrument through a wire.

[0011] Preferably, the upper end of the reserved drain pipe is open, and several pipe holes are provided at the upper end of the reserved drain pipe. The part of the upper end of the drain pipe provided with the pipe holes is inserted into the sump. A filter screen is covered on the sump, and the height of the top surface of the sump corresponds to the designed elevation of the foam concrete.

[0012] Preferably, the primary support of the tunnel includes advanced small ducts, double-layer steel wire meshes, and steel arch frames. The steel arch frames are arranged on the outside of the tunnel. The advanced small ducts and the double-layer steel wire meshes are both arranged on the side of the steel arch frame close to the karst cave. The advanced small ducts are arranged outside the double-layer steel wire mesh. The upper end of the double-layer steel wire mesh is connected with cartridge bolts. A drainage ditch is constructed on the inverted arch, and the inverted arch below the top surface of the drainage ditch is backfilled with concrete; the pile cap is a special-shaped pile cap, a steel wire mesh is laid at the bottom, a reserved notch is provided at the top, and the end of the steel arch frame is fixed in the reserved notch.

[0013] The beneficial effects of the present utility model are as follows:

[0014] 1) The present utility model uses a hoisting machine as a device for splicing and lowering the steel pipe piles and steel reinforcement cages in sections. The clamping hand can be detachably installed outside the sliding plate according to needs. By modifying the hoisting machine and replacing the clamping hand, the switching between the construction of clamping and lowering the steel pipe piles and the steel reinforcement cages can be realized, which well solves the problem of construction limitation in the tunnel with low clearance.

[0015] 2) The utility model casts the pile cap into a special shape to fit the shape of the inverted arch. At the same time, a notch is reserved at the top of the pile cap for splicing with the steel arch frame, which is more conducive to the overall stress of the tunnel structure, forming a special-shaped concrete pile cap system at the pile top; for the unfilled part in the karst cave, the method of using anchor rods and adjustable struts is adopted to form a large hall-type karst cave side wall anchoring and supporting system, effectively preventing the collapse of the karst cave side wall.

[0016] 3) The utility model installs a grouting position monitor at the designed grouting position to form an automatic control system for the backfill grouting elevation of foamed concrete, ensuring the quality of concrete backfill and the accuracy of the backfill position; several drain pipes and a sump are reserved in the karst cave to form a reserved drainage system in the karst cave, realizing the smooth drainage in the tunnel and effectively reducing the pressure on the waist of the tunnel arch. Brief Description of the Drawings

[0017] Figure 1 is the top view of the layout plan of steel pipe piles;

[0018] Figure 2 is the cross-sectional view of the treatment of the karst cave;

[0019] Figure 3 is the schematic diagram of the hoisting and lowering of steel pipe piles;

[0020] Figure 4 is the schematic diagram of the splicing process of steel pipe piles;

[0021] Figure 5 is the schematic diagram of the steel pipe pile gripper;

[0022] Figure 6 is the schematic diagram of the steel reinforcement cage gripper;

[0023] Figure 7 is the schematic diagram of the backfill of foamed concrete;

[0024] Figure 8 is the schematic diagram of the connection between the steel arch frame and the pile cap;

[0025] Figure 9 is the schematic diagram of the connection between the anchor rod and the adjustable strut;

[0026] Figure 10 is the top view of the drainage system;

[0027] Figure 11 is the structural diagram of the grouting position monitor.

[0028] In the figure: 1 - clay, 2 - bearing platform, 3 - hoisting machinery, 301 - hydraulic telescopic rod, 302 - sliding plate, 303 - movable clamping hand, 304 - fixed clamping hand, 305 - adjustable counterweight, 306 - rotating shaft, 307 - support rod, 308 - crawler, 4 - steel pipe pile, 5 - steel bar mesh, 6 - drill hole, 7 - anchor rod, 8 - adjustable strut, 9 - shotcrete, 10 - reserved drain pipe, 11 - grouting position monitor, 12 - grouting pipe, 13 - foam concrete, 14 - inverted arch, 15 - secondary lining, 16 - reserved notch, 17 - steel arch frame, 18 - backing plate, 19 - nut, 20 - pipe orifice, 21 - pipe hole, 22 - sump, 23 - filter screen, 24 - conductive part, 25 - insulating part, 26 - hollow part, 27 - pressure sensor, 28 - karst cave, 29 - tunnel excavation contour line, 30 - locking foot steel pipe, 31 - cartridge anchor rod, 32 - advanced small duct, 33 - double-layer steel bar mesh, 34 - primary support of inverted arch, 35 - concrete, 36 - receiving instrument, 37 - drainage ditch, 38 - cable trench, 39 - steel pipe pile hoop, 40 - double-layer fork, 41 - wire. Detailed implementation mode

[0029] The following further describes the present utility model in conjunction with embodiments. The description of the following embodiments is only used to help understand the present utility model. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present utility model, several modifications can still be made to the present utility model, and these improvements and modifications also fall within the protection scope of the claims of the present utility model.

[0030] Embodiment 1

[0031] As an embodiment, this comprehensive treatment structure for a tunnel crossing a large karst cave includes: a bearing platform 2, hoisting machinery 3, a drainage system, a grouting position monitor 11, foam concrete 13, an inverted arch 14, a secondary lining 15, and the initial support of the tunnel;

[0032] The clay 1 in the karst cave 28 is excavated to below the bottom of the tunnel. A bearing platform 2 is provided below the tunnel in the karst cave 28. Steel pipe piles 4 are driven into the clay 1 from the bottom of the bearing platform 2. The drainage system includes a reserved drain pipe 10 and a sump 22. Foam concrete 13 is poured above the clay 1. A grouting position monitor 11 and a sump 22 are provided at the pouring elevation position of the foam concrete 13; an automatic control system for the elevation of foam concrete backfill grouting is formed, ensuring the quality of concrete backfill and the accuracy of the backfill position.

[0033] One end of the reserved drain pipe 10 is inserted into the sump 22, and the other end extends into the drainage ditch 37 in the tunnel, forming a reserved drainage system for the karst cave, realizing the smooth drainage in the tunnel and effectively reducing the pressure on the tunnel arch waist.

[0034] The hoisting machine 3 includes a hydraulic telescopic rod 301, a sliding plate 302, a clamping hand, an adjustable counterweight 305, a rotating shaft 306, a support rod 307 and a crawler 308. The clamping hand is detachably installed on the outside of the sliding plate 302. The clamping hand includes a movable clamping hand 303 and a fixed clamping hand 304, and is used to clamp the steel pipe pile 4 for hoisting and the steel reinforcement cage of the bearing platform 2. The fixed clamping hand 304 is fixed at the bottom of the sliding plate 302, and the movable clamping hand 303 moves up and down along the sliding plate 302 above the fixed clamping hand 304.

[0035] When the clamping hand is a clamping hand for clamping the steel pipe pile 4, both the movable clamping hand 303 and the fixed clamping hand 304 are provided with steel pipe pile hoops 39. When the clamping hand is a clamping hand for clamping the steel reinforcement cage, the movable clamping hand 303 and the fixed clamping hand 304 are provided with double-layer forks 40.

[0036] The initial support of the tunnel includes advanced small pipes 32, a double-layer steel mesh 33 and a steel arch frame 17. The steel arch frame 17 is arranged on the outside of the tunnel. Both the advanced small pipes 32 and the double-layer steel mesh 33 are arranged on the side of the steel arch frame 17 close to the karst cave 28. The advanced small pipes 32 are arranged on the outside of the double-layer steel mesh 33. The upper end of the double-layer steel mesh 33 is connected with cartridge bolts 31. A drainage ditch 37 is constructed on the inverted arch 14, and the inverted arch 14 below the top surface of the drainage ditch 37 is backfilled with concrete 35. The bearing platform 2 is a special-shaped bearing platform, with a steel mesh 5 laid at the bottom and a reserved notch 16 at the top. The end of the steel arch frame 17 is fixed in the reserved notch 16.

[0037] Embodiment 2

[0038] As another embodiment, on the basis of Embodiment 1, this Embodiment 2 proposes another more specific comprehensive treatment structure for a tunnel passing through a large karst cave:

[0039] Rock bolts 7 are driven into the rock walls on both sides of the unfilled part of the karst cave 28, and an adjustable strut 8 is installed between the ends of the rock bolts 7 on both rock walls to form a large hall-type karst cave side wall anchoring and supporting system, effectively preventing the collapse of the karst cave side wall. The ends of the rock bolts 7 are anchored to the rock wall with backing plates 18 and nuts 19. The two ends of the adjustable strut 8 are concave and clamped with the ends of the rock bolts 7. The rock wall is sprayed with concrete 9.

[0040] The grouting position monitor 11 includes a conductive part 24, an insulating part 25, a hollow part 26 and a pressure sensor 27. The grouting position monitor 11 is tubular, and the tube wall is obtained by splicing the conductive part 24 and the insulating part 25 in pairs. The pressure sensor 27 is arranged on the insulating part 25 on the top surface of the grouting position monitor 11. The top surface height of the grouting position monitor 11 is the same as the top surface height of the sump 22. The grouting position monitor 11 is connected to a receiving instrument 36 through a wire 41.

[0041] The upper end opening 20 of the reserved drain pipe 10 is open. A number of pipe holes 21 are provided at the upper end of the reserved drain pipe 10. The part of the upper end of the drain pipe 10 where the pipe holes 21 are provided is inserted into the sump 22. A filter screen 23 is covered on the sump 22. The top surface height of the sump 22 corresponds to the design elevation of the foamed concrete 13.

[0042] It should be noted that the same or similar parts in this embodiment and the first embodiment can be referred to each other, and will not be elaborated in this application.

[0043] In this specification, each embodiment is described in a progressive manner. The key point of each embodiment is to illustrate the differences from other embodiments. The same or similar parts among the embodiments can be referred to each other.

Claims

1. A comprehensive treatment structure for a tunnel passing through a large karst cave, characterized in that Including: Pile cap, hoisting machinery, drainage system, grouting position monitor, foamed concrete, inverted arch, secondary lining and initial tunnel support; The clay in the karst cave is dug to below the bottom of the tunnel. A pile cap is provided below the tunnel within the karst cave. Steel pipe piles are driven into the clay from the bottom of the pile cap. The drainage system includes a reserved drain pipe and a sump. Foamed concrete is poured above the clay. A grouting position monitor and a sump are provided at the pouring elevation position of the foamed concrete; one end of the reserved drain pipe is inserted into the sump, and the other end extends into the drainage ditch within the tunnel.

2. The comprehensive treatment structure for a tunnel passing through a large karst cave according to claim 1, characterized in that: The hoisting machinery includes a hydraulic telescopic rod, a sliding plate, clamping hands, adjustable counterweights, a rotating shaft, a support rod and crawlers. The clamping hands are detachably installed on the outside of the sliding plate. The clamping hands include movable clamping hands and fixed clamping hands, and are used for clamping the steel pipe piles and the steel reinforcement cages of the pile caps; the fixed clamping hands are fixed at the bottom of the sliding plate, and the movable clamping hands move up and down along the sliding plate above the fixed clamping hands.

3. The comprehensive treatment structure for a tunnel to pass through a large karst cave according to claim 2, characterized in that: When the clamping hands are the clamping hands for clamping steel pipe piles, both the movable clamping hands and the fixed clamping hands are provided with steel pipe pile hoops; when the clamping hands are the clamping hands for clamping steel reinforcement cages, the movable clamping hands and the fixed clamping hands are provided with double-layer forks.

4. The comprehensive treatment structure for a tunnel passing through a large karst cave according to claim 1, wherein: Anchor bolts are driven into the rock walls on both sides of the unbackfilled part of the karst cave. An adjustable strut is installed between the ends of the anchor bolts on the rock walls on both sides; the ends of the anchor bolts are anchored to the rock walls with backing plates and nuts, and the two ends of the adjustable strut are concave and clamped with the ends of the anchor bolts; concrete is sprayed on the rock walls.

5. The comprehensive treatment structure for a tunnel passing through a large karst cave according to claim 1, wherein: The grouting position monitor includes a conductive part, an insulating part, a hollow part and a pressure sensor. The grouting position monitor is tubular, and the pipe wall is obtained by splicing the conductive part and the insulating part opposite to each other in pairs. The pressure sensor is arranged on the insulating part on the top surface of the grouting position monitor. The top surface height of the grouting position monitor is the same as the top surface height of the sump. The grouting position monitor is connected to a receiving instrument through a wire.

6. The comprehensive treatment structure for a tunnel passing through a large karst cave according to claim 1, characterized in that: The upper end opening of the reserved drain pipe is open. A number of pipe holes are provided at the upper end of the reserved drain pipe. The part of the drain pipe with pipe holes at the upper end is inserted into the sump. A filter screen is covered on the sump. The top surface height of the sump corresponds to the designed elevation of the foamed concrete.

7. The comprehensive treatment structure for a tunnel passing through a large karst cave according to claim 1, characterized in that: The initial tunnel support includes advanced small ducts, double-layer steel mesh and steel arch frames. The steel arch frames are arranged on the outside of the tunnel. The advanced small ducts and the double-layer steel mesh are both arranged on the side of the steel arch frame close to the karst cave. The advanced small ducts are arranged outside the double-layer steel mesh. The upper end of the double-layer steel mesh is connected with cartridge bolts. A drainage ditch is constructed on the inverted arch, and concrete is backfilled on the inverted arch below the top surface of the drainage ditch; the pile cap is a special-shaped pile cap, with a steel mesh laid at the bottom and a reserved notch at the top. The end of the steel arch frame is fixed in the reserved notch.

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