Water-rich fractured rock tunnel supporting and draining integrated structure

Abstract

The utility model relates to the technical field of tunnel water prevention and drainage, in particular to a water-rich fractured rock mass tunnel supporting and drainage integrated structure which comprises a plurality of arc-shaped arch frame drainage devices, longitudinal drainage pipes are arranged at the two ends of each arch frame drainage device, and the longitudinal drainage pipes are communicated with a central drainage groove through transverse drainage pipes. A forepoling drainage pipe shed is arranged on the outer wall of the lagging jack drainage device; the forepoling drainage pipe shed comprises a steel pipe, one end of the steel pipe is connected with the arch drainage device, the other end of the steel pipe is connected with a taper pipe, the taper pipe is provided with drainage holes and connected with a forepoling drainage pipe through a closed ring, and one end of the forepoling drainage pipe is connected to the arch drainage device. According to the utility model, drainage can be carried out while tunnel construction is carried out, and the problem that the construction progress is delayed due to long drainage time of water-rich rock mass is effectively solved; meanwhile, the drainage guide pipes are added in the pipe shed and the arch frame, the function of blind pipes is replaced, arrangement of annular blind pipes is omitted, the construction difficulty is lowered, and the construction efficiency is guaranteed.

Description

Technical Field

[0001] The utility model relates to the technical field of tunnel waterproofing and drainage, in particular to an integrated support and drainage structure for a water-rich fractured rock mass tunnel. Background Art

[0002] In engineering projects, one method is often adopted, such as advance drilling drainage and grouting water blocking, to release water pressure in advance or block water pressure on the face of the tunnel to maintain the stability of the face; the second method is to install an advance large pipe shed on the tunnel vault in the water-rich fracture section to stabilize the advance core soil in front of the face from a mechanical point of view; the third method is to set a waterproof layer between the primary support and the secondary lining to isolate the seepage water outside the tunnel, and at the same time, set annular blind pipes at regular intervals along the longitudinal direction of the tunnel between the waterproof layer and the primary support for drainage, and finally discharge the seepage water in the tunnel out of the tunnel through longitudinal drainage pipes, transverse drainage pipes and central drainage ditches.

[0003] However, during the construction of the tunnel in the water-rich fractured rock mass section, the conventional tunnel support and drainage structure has the following problems:

[0004] (1) Pre-drilling can achieve the purpose of pre-drilling, but it increases the process and cost;

[0005] (2) Water-rich fractured sections are the key sections for waterproofing and drainage during both tunnel construction and operation. Pre-drilling water exploration can only achieve the purpose of early water exploration and water pressure release during the construction phase, but has no effect on the water pressure in the fractured rock mass during the operation phase.

[0006] (3) Setting blind pipes at regular intervals between the waterproof layer and the initial support can effectively drain the seepage water from the outer layer of the waterproof layer in normal tunnel construction sections. However, in water-rich fracture sections, even if the blind pipe spacing is reduced, the drainage effect is still poor.

[0007] Therefore, if the problem of fissure water cannot be properly handled during the construction and operation of tunnels in water-rich fissure rock sections, the strength of weak rock masses such as broken zones will inevitably be further reduced, adding more uncertainty factors to the stability of tunnel projects where "nine out of ten tunnels are seeping." Utility Model Content

[0008] The utility model aims to provide an integrated support and drainage structure for a water-rich fractured rock tunnel, so as to solve the problems mentioned in the background technology of complex procedures, high costs and poor drainage effect during the construction of a water-rich fractured rock section of a tunnel.

[0009] The utility model adopts the following technical solutions:

[0010] The utility model provides an integrated support and drainage structure for a water-rich fractured rock mass tunnel, which comprises a plurality of arc-shaped arch drainage devices, both ends of which are provided with longitudinal drainage pipes, the longitudinal drainage pipes being connected with a central drainage groove arranged along the axis direction through a plurality of transverse drainage pipes, and a plurality of advanced support drainage pipe sheds inclined outwardly along the axis direction are arranged on the outer wall of the arch drainage device;

[0011] The advance support drainage pipe shed includes a steel pipe, one end of which is connected to the arch drainage device, and the other end is connected to the cone pipe, the cone pipe is provided with a drainage hole, and a closed ring is provided at the connection between the steel pipe and the cone pipe, an advance drainage pipe is connected to the inner diameter of the closed ring, and one end of the advance drainage pipe is connected to the arch drainage device.

[0012] Furthermore, the arch drainage device includes an arc-shaped arch support frame, in which an arc-shaped drainage pipe is arranged, and the arc-shaped drainage pipe is fixedly connected to the arch support frame through a plurality of support rods, and a plurality of pipe openings are circumferentially arranged on the outer wall of the arc-shaped drainage pipe, and the pipe openings are connected to the advance drainage pipe, and the two ends of the arc-shaped drainage pipe are respectively connected to the corresponding longitudinal drainage pipes.

[0013] Furthermore, the pipe opening is connected to the advance drainage pipe via a flange.

[0014] Furthermore, the advance drainage pipe is fixed at the center position of the steel pipe by fixing steel bars.

[0015] Furthermore, the steel pipe is provided with multiple rows of grouting holes along the axial direction.

[0016] Furthermore, the pipe-roof steel pipe is formed by splicing together multiple sections of steel pipes.

[0017] Furthermore, geotextile is laid in the conical tube.

[0018] Compared with the prior art, the beneficial technical effects of the utility model are:

[0019] (1) Integrate advance support and advance drainage to simplify construction steps, shorten rock mass stabilization time, ensure the stability of the face and surrounding rock in the excavation direction during excavation, and prevent water gushing and steel bar corrosion caused by tunnel excavation.

[0020] (2) Since drainage conduits are added to support systems such as pipe sheds and arch frames to replace the function of blind pipes, the arrangement of annular blind pipes can be eliminated in the lining, reducing construction difficulty and ensuring construction efficiency.

[0021] (3) Since the pipe shed is mainly set up for advance support, by adding a drainage system to the pipe shed for advance drainage, it is possible to drain water while tunnel construction is being carried out, effectively solving the problem of long drainage time for water-rich rock mass and delaying construction progress.

[0022] The utility model can drain water while constructing a tunnel, effectively solving the problem that the drainage time of water-rich rock mass is long and thus delays the construction progress; at the same time, drainage ducts are added to the pipe shed and the arch frame to replace the function of the blind pipe, thereby eliminating the arrangement of the annular blind pipe, reducing the construction difficulty and ensuring the construction efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The utility model will be further described below in conjunction with the accompanying drawings.

[0024] Figure 1 It is a schematic diagram of the integrated structure of support and drainage for a water-rich fractured rock tunnel in an embodiment of the utility model;

[0025] Figure 2 It is a structural schematic diagram of a pipe shed in an embodiment of the utility model;

[0026] Figure 3 It is a cross-sectional view of the cone tube in the embodiment of the utility model;

[0027] Figure 4 It is a cross-sectional view of the pipe rack in the embodiment of the utility model.

[0028] Explanation of the reference numerals in the accompanying drawings: 1. Arch drainage device; 101. Arch support frame; 102. Arc drainage pipe; 103. Support rod; 104. Pipe mouth; 2. Longitudinal drainage pipe; 3. Horizontal drainage pipe; 4. Central drainage trough; 5. Advance support drainage pipe shed; 501. Pipe shed steel pipe; 502. Conical pipe; 503. Drainage hole; 504. Advance drainage pipe; 505. Grouting hole; 6. Closing ring; 7. Flange; 8. Fixed steel bar; 9. Geotextile; 10. Initial support; 11. Waterproof layer. DETAILED DESCRIPTION

[0029] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0030] like Figure 1 As shown, the present embodiment discloses an integrated support and drainage structure for a water-rich fractured rock tunnel, comprising a plurality of arc-shaped arch drainage devices 1, both ends of which are provided with longitudinal drainage pipes 2, which are connected to a central drainage trough 4 arranged along the axial direction through a plurality of transverse drainage pipes 3, and a plurality of advance support drainage pipe sheds 5 inclined outward along the axial direction are provided on the outer wall of the arch drainage device 1.

[0031] The advance support drainage pipe rack 5 includes a pipe rack steel pipe 501, one end of which is connected to the arch frame drainage device 1, and the other end is connected to the cone pipe 502, and the cone pipe 502 is provided with a drainage hole 503. A closed ring 6 is provided at the connection between the pipe rack steel pipe 501 and the cone pipe 502, and an advance drainage pipe 504 is connected to the inner diameter of the closed ring 6, and one end of the advance drainage pipe 504 is connected to the arch frame drainage device 1.

[0032] In this embodiment, the arch drainage device 1 includes an arc-shaped arch support frame 101, in which an arc-shaped drainage pipe 102 is arranged, and the arc-shaped drainage pipe 102 is fixedly connected to the arch support frame 101 through a plurality of support rods 103. A plurality of pipe openings 104 are circumferentially arranged on the outer wall of the arc-shaped drainage pipe 102, and the pipe openings 104 are connected to the advance drainage pipe 504, and the two ends of the arc-shaped drainage pipe 102 are respectively connected to the corresponding longitudinal drainage pipes 2.

[0033] In this embodiment, the pipe opening 104 is connected to the advance drainage pipe 504 via a flange 7, and a rubber ring is placed in the middle of the connection position of the flange 7 to prevent water leakage at the interface.

[0034] In this embodiment, the advance drainage pipe 504 is fixed to the center position of the pipe rack steel pipe 501 by welding the fixing steel bars 8 .

[0035] In this embodiment, multiple rows of grouting holes 505 are arranged along the axial direction on the pipe-roof steel pipe 501 to ensure that the grouting material flows out evenly during the grouting process, avoiding excessive accumulation or deficiency of the grouting material in a certain area, thereby ensuring the overall uniformity and consistency of the grouting effect.

[0036] In this embodiment, the pipe-roof steel pipe 501 is formed by splicing multiple sections of steel pipes, and every two adjacent sections of steel pipes are connected by pipe clamps and threads.

[0037] In this embodiment, a geotextile 9 is laid inside the conical tube 502 .

[0038] Based on the above-mentioned integrated support and drainage structure for a water-rich fractured rock mass tunnel, the present embodiment also discloses a construction method thereof, which mainly includes the following steps:

[0039] Step 1: When the tunnel excavation approaches the water-rich fracture zone, switch to manual excavation to reduce soil disturbance, level the face surface, and clean up the surrounding broken soil.

[0040] Step 2: Drive the advance support drainage pipe shed 5 in a circular manner along the periphery of the face, with an external insertion angle of 1 to 2 degrees, a longitudinal overlap length of not less than 2m, and a circumferential spacing of not more than 0.6m. When water flows out of the drainage pipe, a temporary drainage system is established to drain the groundwater.

[0041] Step 3: An arch drainage device 1 is erected along the face, and an arc-shaped drainage pipe 102 is arranged inside the arch drainage device 1. The pipe mouth 104 of the arc-shaped drainage pipe 102 must correspond to the advance drainage pipe 504. The pipe mouth 104 and the advance drainage pipe 504 are connected through a flange 7, and a rubber ring is placed in the middle to prevent water leakage at the interface.

[0042] Then, multiple sections of pipe-roof steel pipes 501 are sequentially sleeved on the advance drainage pipe 504, wherein the pipe-roof steel pipes 501 close to the pipe opening 104 are connected to the arch support frame 101 by welding, and the remaining pipe-roof steel pipes 501 are connected by pipe clamps and threads.

[0043] The inner diameter of the closed ring 6 is the same as that of the advanced drainage pipe 504, and it is welded to the end of the advanced drainage pipe 504 to ensure welding strength. The outer diameter of the closed ring 6 is slightly smaller than the inner diameter of the pipe-roof steel pipe 501. The advanced drainage pipe 504 welded with the closed ring 6 is inserted into the appropriate position of the last pipe-roof steel pipe 501, and then the closed ring 6 is welded to the inner wall of the pipe-roof steel pipe 501 to make it completely closed, and then the geotextile 9 is laid in the remaining part of the pipe-roof steel pipe 501, and its end is processed into a cone 502.

[0044] The pipe-roof steel pipe 501 is provided with a pipe-roof grouting port at one end close to the arch drainage device 1, and cement mortar is poured into the pipe-roof steel pipe 501 through the grouting port. The pipe-roof steel pipe 501, the advanced drainage pipe 504 and the closed ring 6 must be tightly connected to prevent cement mortar from penetrating into the advanced drainage pipe 504 and the cone pipe 502, causing pipe blockage. For the fixation of the advanced drainage pipe 504, the steel bar 8 can be inserted from the slurry outlet hole of the pipe-roof steel pipe 501, the position of the advanced drainage pipe 504 is adjusted to be centered, and the steel bar 8 is welded at the slurry outlet hole of the pipe-roof steel pipe 501. The pipe-roof steel pipe 501 is welded to the arch support frame 101 of the arch drainage device 1, so that the advanced support drainage pipe shed 5 and the arch drainage device 1 are connected as a whole; concrete is sprayed on the entire arch drainage device 1 and the steel mesh to form an initial support 10.

[0045] Step 4: A longitudinal drainage pipe 2 connected to the arc drainage pipe 102 is laid at the bottom of the tunnel. Transverse drainage pipes 3 are opened on the longitudinal drainage pipe 2 at regular intervals. The transverse drainage pipes 3 are connected to the central drainage trough 4, and the central drainage trough 4 leads the groundwater out of the tunnel.

[0046] Step 5: Smooth the inner wall of the initial support, polish the wall surface, and then lay a waterproof layer 11 on the inner wall of the tunnel.

[0047] The embodiments described above are only descriptions of the preferred methods of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should fall within the protection scope determined by the claims of the present invention.

Claims

1. An integrated support and drainage structure for a water-rich fractured rock tunnel, characterized in that: It comprises a plurality of arc-shaped arch drainage devices (1), both ends of the plurality of arch drainage devices (1) are provided with longitudinal drainage pipes (2), the longitudinal drainage pipes (2) are connected to a central drainage groove (4) arranged along the axial direction through a plurality of transverse drainage pipes (3), and a plurality of advanced support drainage pipe sheds (5) inclined outward along the axial direction are provided on the outer wall of the arch drainage device (1); The advanced support drainage pipe shed (5) comprises a pipe shed steel pipe (501), one end of the pipe shed steel pipe (501) is connected to the arch drainage device (1), and the other end is connected to the cone pipe (502), a drain hole (503) is provided on the cone pipe (502), a closed ring (6) is provided at the connection between the pipe shed steel pipe (501) and the cone pipe (502), an advanced drainage pipe (504) is connected to the inner diameter of the closed ring (6), and one end of the advanced drainage pipe (504) is connected to the arch drainage device (1).

2. The integrated support and drainage structure for a water-rich fractured rock tunnel according to claim 1 is characterized in that: The arch drainage device (1) comprises an arc-shaped arch support frame (101), an arc-shaped drainage pipe (102) is arranged in the arch support frame (101), the arc-shaped drainage pipe (102) is fixedly connected to the arch support frame (101) via a plurality of support rods (103), a plurality of pipe openings (104) are arranged on the outer wall of the arc-shaped drainage pipe (102) along the circumferential direction, the pipe openings (104) are connected to the advance drainage pipe (504), and the two ends of the arc-shaped drainage pipe (102) are respectively connected to the corresponding longitudinal drainage pipe (2).

3. The integrated support and drainage structure for a water-rich fractured rock tunnel according to claim 2 is characterized in that: The pipe opening (104) is connected to the advance drainage pipe (504) via a flange (7).

4. The integrated support and drainage structure for a water-rich fractured rock tunnel according to claim 1 is characterized in that: The advanced drainage pipe (504) is fixed to the center position of the pipe rack steel pipe (501) by fixing steel bars (8).

5. The integrated support and drainage structure for a water-rich fractured rock tunnel according to claim 1 is characterized in that: The pipe-roof steel pipe (501) is provided with multiple rows of grouting holes (505) along the axial direction.

6. The integrated support and drainage structure for a water-rich fractured rock tunnel according to claim 1 is characterized in that: The pipe rack steel pipe (501) is formed by splicing together multiple sections of steel pipes.

7. The integrated support and drainage structure for a water-rich fractured rock tunnel according to claim 1 is characterized in that: A geotextile (9) is laid inside the conical tube (502).

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