JP2007186848A - Drainage method for tunnel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a drainage method for a tunnel which can reduce the amount of treatment of sump water by accurately grasping the position and direction of a sump water surface without the use of a dedicated boring machine. <P>SOLUTION: An advancing exploratory borehole 11a is bored from a right half 8a of the face 7 of the tunnel 3, and the presence of the sump water in a tunnel planning position 5 is checked from the result of investigation. An advancing exploratory borehole 11b is bored from a left half 8b of the face 7, and the position and direction of the sump water surface 15 are grasped from the result of investigation by advancing exploratory boring in the boreholes 11a and 11b. Subsequently, after the tunnel 3 is bored up to this side of the sump water surface 15, drainage boring 29a and drainage boring 29b are applied for drainage toward the sump water surface 15 from side surfaces 13a and 13b of the tunnel 3. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for draining a tunnel.

  Conventionally, when constructing a tunnel, first, an advanced survey boring is carried out from the tunnel face to check the spring condition at the planned position (see, for example, Patent Document 1). Water draining has been carried out by constructing water draining bores from the bottom, side surfaces, etc. in the vicinity (see, for example, Patent Document 2).

JP 2001-324575 A Japanese Patent Publication No. 5-6636

  However, in the conventional advanced survey boring, since the borehole is one, the position and direction of the assumed spring surface could not be accurately grasped. In addition, since the drilling bends when the bedrock is hard, a drilling machine dedicated to advanced survey boring of large diameter and long length (length L = about 200 m, diameter = 100 mm or more) was necessary. With regard to draining boring, a large-diameter and long-sized advanced survey boring machine was necessary.

The present invention has been made in view of such problems, and the object of the present invention is to accurately grasp the position and direction of the spring surface without using a dedicated boring machine, and to reduce the amount of spring water treated. It is to provide a method for draining the tunnel.

  The present invention for achieving the above-described object includes the step (a) of obtaining at least two advanced survey boreholes from the face of the tunnel and obtaining the survey results on the spring water, and from the survey results, A step (b) of grasping the position and direction, a step (c) of excavating a tunnel to the front of the spring surface, and a step (d) of constructing a drain boring from the side surface of the tunnel toward the spring surface. A method for draining a tunnel, comprising:

  In step (a), it is desirable to perform advanced survey boring from the left half and right half of the face. In the step (a), for example, the first advanced survey boring is performed from one of the left half and the right half of the face, and then the second advanced survey boring is performed from the other. In step (a), it is desirable to carry out the second advanced survey boring at a distance of about 1 m from the side wall of the tunnel.

  In step (a), advanced survey boring is performed using a drill jumbo. In the step (c), a tunnel is excavated from the spring surface grasped in the step (b) to about 5 m. In the step (d), the drain boring is constructed so that the covering on the spring surface is about the inner diameter of the tunnel.

  ADVANTAGE OF THE INVENTION According to this invention, the drainage method of the tunnel which can grasp | ascertain the position and direction of a spring surface with high precision, without using a dedicated boring machine, and can reduce the processing amount of spring water can be provided.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a diagram illustrating a process of confirming the presence or absence of spring water. 1A is a plan view in the vicinity of the tunnel planned position 5, and FIG. 1B is an elevational view in the vicinity of the tunnel planned position 5. FIG. FIG. 1A is a cross-sectional view taken along arrow AA in FIG. In the present embodiment, a water draining method when excavating the tunnel 3 at the tunnel planned position 5 of the natural ground 1 will be described.

  When excavating the tunnel 3, first, as shown in FIG. 1, the advanced survey boring hole 11 a is drilled from the right half 8 a of the face 7 of the tunnel 3 using a drill jumbo 9. And the presence or absence of the spring water in the tunnel plan position 5 is confirmed from the survey result of the advanced survey boring in the advanced survey boring hole 11a. The length of the advanced survey boring hole 11a is, for example, about 50 m.

  FIG. 2 shows a plan view of a rod system 17 used for drilling advanced survey boreholes. As shown in FIG. 2, the rod system 17 includes a bit 23 provided at the tip, a guide tube 21 connected to the rear of the bit 23, a rod 19 connected to the rear of the guide tube 21, and the like.

  In the rod system 17, for example, a bit 23 having an outer diameter of 64 mm, a guide tube 19 having an outer diameter of 56 mm, and a rod 19 having an outer diameter of 56 mm are combined. When drilling using a rod system that combines a normal outer diameter 64 mm bit, an outer diameter 55 mm sleeve, and an outer diameter 32 mm rod, the hole bend is a maximum of 10 m at the time of 50 m construction. When drilling using the rod system 17 having a small outer diameter difference between the bit 23 and the rod 19, the hole bend is less than 1 m at the time of 50 m construction, and the drilling accuracy can be remarkably improved.

  FIG. 3 is a plan view showing a process of grasping the position / direction of the spring surface 15. When it is confirmed that spring water exists in the process shown in FIG. 1, next, as shown in FIG. 3, the advanced survey boring hole is drilled using the drill jumbo 9 from the left half 8 b of the face 7 of the tunnel 3. 11b is drilled. The advanced survey boring hole 11 b is drilled at a position about 1 m away from the side wall 13 b of the tunnel 3. The length of the advanced research boring hole 11b is approximately the same as that of the advanced research boring hole 11a.

  In the process shown in FIG. 3, the position / direction of the spring surface 15 at the tunnel planned position 5 is grasped from the result of the investigation of the advanced investigation boring hole 11a and the advanced investigation boring hole 11b.

  FIG. 4 is a plan view showing a process of excavating the tunnel 3. After grasping the position and direction of the spring surface 15 in the process shown in FIG. 3, the tunnel 3 is excavated to a cover lock position about 5 m before the spring surface 15 as shown in FIG.

  FIG. 5 is a plan view showing a process of preparing for construction of drain boring. After excavating the tunnel 3 to the front of the spring surface 15 as shown in FIG. 4, a box opening 25a and a box opening 25b are respectively constructed on the side wall 13a and the side wall 13b of the tunnel 3 as shown in FIG. 5. . The box opening 25a and the box opening 25b are arranged in a staggered manner in front of the face 7a of the tunnel 3.

  Next, a hole is drilled from the box punching 25a to the natural ground 1, and the mouth tube 27a is attached. Further, a hole is drilled from the box punching 25b to the natural ground 1, and the mouth tube 27b is attached.

  FIG. 6 is a plan view showing a process of constructing drain boring. After preparing for the construction of draining boring as shown in FIG. 5, the draining boring 29a is constructed from the mouth tube 27a to the spring surface 15 as shown in FIG. The drain boring 29a is constructed so that the distance 31a from the side surface 13a of the tunnel 3 to the location where the drain boring 29a reaches the spring surface 15 is about the inner diameter of the tunnel 3.

  Further, a draining boring 29b is constructed from the mouth pipe 27b to the spring surface 15. The drain boring 29b is constructed so that the distance 31b from the side surface 13b of the tunnel 3 to the location where the drain boring 29b reaches the spring surface 15 is about the inner diameter of the tunnel 3.

  FIG. 7 is a plan view showing a step of further excavating the tunnel 3. After constructing the draining boring as shown in FIG. 6, the tunnel 3 is further excavated beyond the spring surface 15 as shown in FIG. 7.

As described above, in this embodiment, by using the rod system 17 having a small outer diameter difference between the bit 23 and the rod 19 as shown in FIG. 2, the drill jumbo 9 is used without using a dedicated boring machine. Advanced survey boring with high accuracy. In addition, since two advanced survey borings are carried out, the position and direction of the spring surface 15 can be accurately grasped.

  Further, after the tunnel 3 is excavated to the front of the spring surface 15 by accurately grasping the position and direction of the spring surface 15, the drain boring 29a and the drain boring 29b are removed from the tunnel side surface 13a and the side surface 13b in front of the face 7a. Because it is constructed, shorter drainage boring is required compared to the conventional method, and at the same time, the amount of spring water treatment is reduced.

  In FIG. 1 and FIG. 3, advanced survey boring is first performed in the right half 8a of the tunnel 3 and then in the left half 8b. However, the survey position and the survey order are not limited thereto. Advanced survey boring shall be conducted in at least two locations.

Further, in FIG. 5, the number of draining borings is two, but the number may not be two. Water drain boring is added until the spring pressure reaches an appropriate value.

  As mentioned above, although preferred embodiment of the draining method of the tunnel concerning this invention was described referring an accompanying drawing, this invention is not limited to this example. It is obvious for those skilled in the art that various modifications or modifications can be conceived within the scope of the technical idea described in the claims, and these are naturally within the technical scope of the present invention. It is understood that it belongs.

The figure which shows the process of checking the presence or absence of spring water Plan view of rod system 17 used for drilling advanced survey boreholes The top view which shows the process of grasping | ascertaining the position and direction of the spring surface 15 Plan view showing the process of excavating the tunnel 3 Plan view showing the process of preparing for draining boring Plan view showing the process of constructing drain boring The top view which shows the process of further excavating the tunnel 3

Explanation of symbols

1 ……… Machiyama 3 ……… Tunnel 5 ……… Tunnel planning position 7, 7a ……… Face 8a ……… Right half 8b ……… Left half 9 ……… Drill jumbo 11a, 11b …… ... Advanced survey boring holes 13a, 13b ......... Side wall 15 ......... Spring surface 29a, 29b ...... Drain boring 31a, 31b ......... Distance

Claims (6)

(A) a step of conducting at least two advanced survey boreholes from the face of the tunnel and obtaining survey results on spring water;
From the survey results, the step (b) of grasping the position and direction of the spring surface,
A step (c) of excavating a tunnel just before the spring surface,
A step (d) of constructing a drain boring from the side of the tunnel toward the spring surface;
A method for draining a tunnel, comprising:   2. The tunnel draining method according to claim 1, wherein in the step (a), the advanced survey boring is performed from the left half and the right half of the face.   2. The tunnel draining method according to claim 1, wherein the second advanced survey boring is performed at a distance of about 1 m from the side wall of the tunnel in the step (a).   The tunnel draining method according to claim 1, wherein the advanced survey boring is performed using a drill jumbo in the step (a).   2. The tunnel draining method according to claim 1, wherein in the step (c), the tunnel is excavated to about 5 m before the spring surface.   2. The tunnel draining method according to claim 1, wherein in the step (d), the draining boring is constructed such that the covering on the spring surface is about the inner diameter of the tunnel.

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