JP2876102B2 - Perforator for the outer periphery of tunnel face - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drilling device for drilling a hole at a predetermined depth along a perimeter of a planned tunnel at a predetermined angle in a tunnel length direction in a tunnel face when excavating a tunnel. is there.

[0002]

2. Description of the Related Art When a tunnel is excavated by a blasting method, first, holes or slots having a predetermined depth are formed at appropriate intervals along the outer periphery of a planned tunnel in a tunnel face, and the tunnel is surrounded by the holes or slots. After drilling a large number of blast holes in a face, a tunnel portion having a predetermined length is excavated by charging the blast holes and blasting them.
Conventionally, as shown in FIG. 3, a drilling machine D having a rod body C having a bit B attached to a tip thereof on a guide base A rotatable vertically and horizontally is used as such a drilling device. There is known an apparatus which is freely mounted and configured to advance a drilling machine D while rotating and hitting a rod body C to pierce with a tip bit B.

When the hole E is drilled along the outer periphery of the planned tunnel by the drilling device configured as described above, the upper half of the body of the drill D protrudes upward from the axis of the rod C. The protruding portion abuts on the peripheral wall F of the already excavated tunnel portion, so that a horizontal hole cannot be formed in the length direction of the tunnel from the outer peripheral line of the planned tunnel. Therefore, as shown in the figure, the rod body C of the drilling machine D is set to be inclined obliquely outward toward the tip, that is, set so as to have a predetermined cutting angle (piercing angle). Drilling work is performed sequentially, and the tunnel wall surface is drilled so as to have a stepped cross section in the length direction of the tunnel.

[0004]

However, in the above-mentioned conventional drilling device, the length of the rod body C must be equal to the hole E to be drilled.
Since the hole E is formed to a size substantially equal to the depth, when the hole E is drilled to a predetermined depth, the drilling machine D reaches the vicinity of the face face, and accordingly requires a relatively large measuring angle and sequentially. There is a problem that the level difference of the hole E to be drilled becomes large, and the lining concrete to be constructed after excavation becomes unnecessarily thick and uneconomical. SUMMARY OF THE INVENTION It is an object of the present invention to provide a drilling device for an outer peripheral portion of a face of a tunnel face, which can make a cutting angle of a drilling rod body of the drilling machine as small as possible.

[0005]

In order to achieve the above-mentioned object, the present invention provides a drilling device for an outer peripheral portion of a face of a tunnel face, in which a guide table is provided on a traveling vehicle, and a bit is provided at the tip on the guide table. A drilling machine configured to mount a drilling machine having a mounted rod body back and forth so as to be able to move back and forth, and to advance the drilling machine so as to drill a hole of a constant depth in a tunnel length direction in a face face, The rod body is formed to have a length that is at least twice the depth of the hole to be bored.

[0006]

When drilling in the tunnel length direction from the outer peripheral portion of the tunnel face by the drilling machine of the above-described punching device, the rod bit is brought into contact with the outer peripheral portion of the face at a predetermined position on the outer peripheral portion of the face. Has a length that is at least twice the depth of the hole to be drilled, so that the body of the drilling machine is located farther away from the face than the conventional device. Even if a hole is drilled, the drill 4 excavates first,
The formed tunnel portion reaches only the second or higher wall portion of the stepped peripheral wall of the cross section, and therefore, the tunnel length portion having the constant cross section is excavated and formed sequentially even if the cutting angle is reduced. It becomes possible.

[0007]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
Reference numeral 1 denotes a truck driven by a caterpillar, on which a boom 2 is pivotally mounted on its front end face so as to be pivotable up, down, left and right, and at the front end of the boom 2 it is pivotable up, down, left, right on the lower surface of a guide base 3 which is long in the longitudinal direction. They are freely connected. Note that the turning rotation of the boom 2 with respect to the traveling vehicle 1 and the turning of the guide table 3 with respect to the boom 2 are performed by a hydraulic jack.
The length of the guide table 3 is longer than the conventional guide table by a dimension substantially equal to the depth (length) of the hole to be drilled.

Reference numeral 4 denotes a boring machine, which is integrally mounted on a gantry 5 slidably disposed in the front-rear direction on the guide base 3 and is provided with a hydraulic cylinder ( (Not shown). The boring machine 4 rotatably supports a rear end portion of a rod body 7 rotated and struck by a drifter 6 on an upper surface of a front end of the gantry 5 so that the rod body 7 faces forward in the length direction of the guide base 3. The front end of the rod body 7 is slidably inserted into a bearing portion 8 provided on the upper surface of the front end of the guide base 3, and a bit 7a is detachably attached to the front end of the rod body 7. In addition, the length of the rod body 7 is formed to be twice or more the depth of the hole to be drilled. Reference numeral 9 denotes a guide base fixing tool disposed on the lower surface side of the front end of the guide base 3.

In order to drill a hole 11 having a constant depth in the tunnel length direction at the outer peripheral portion of the tunnel face 10 by the drilling device thus configured, first, the pedestal 5 is retracted and the pedestal 5 is placed on the pedestal 5. With the drilling machine 4 positioned at the rear of the guide table 3,
In this state, the traveling vehicle 1 is moved to the vicinity of the face 10 and the boom 2 and the guide table 3 are turned and rotated to turn the length direction of the rod body 7 of the drilling machine 4 in the drilling direction. At the same time, a predetermined angle is set, and the fixing tool 9 is pressed against the outer peripheral portion of the face 10 to fix the guide table 3.

Thereafter, the gantry 5 is advanced by a hydraulic jack while rotating and hitting the rod body 7 of the drilling machine 4, and as shown in FIG. 2, at a predetermined angle and at a predetermined depth in the tunnel length direction. Hole 11 is formed. At this time, since the length of the rod body 7 is formed to be at least twice as long as the depth of the hole 11, even if the hole 11 is drilled to a predetermined depth, the position of the drilling machine 4 is already excavated. After the second step of the stepped peripheral wall section of the formed tunnel section, it reaches only to a position located rearward from the face 10. And after drilling this hole 11,
The rod body 7 is pulled out, and the next outer peripheral portion of the face face at a desired distance from the hole 11 is pierced in the same manner. This operation is repeated to form a large number of holes 11 along the outer peripheral portion of the face face 10.

Further, as is well known, the hole 11
After drilling a number of holes with the same depth as the tunnel in the length direction of the tunnel, these holes are charged with explosives and exploded, or expanded by inserting a cylindrical inflatable body into the holes and expanding. A crack is generated in the rock between the holes, and a tunnel portion corresponding to the depth of the hole is excavated. When a tunnel portion having a predetermined length corresponding to the depth of the hole is sequentially excavated in this manner, the peripheral wall of the tunnel portion is formed with the inclined peripheral wall portion 12 having the same angle as the cutting angle of the drilling machine 4 and the same length as the drilling depth. , A vertical wall portion 13 extending from the rear end of the peripheral wall portion 12 in the radial direction of the tunnel.
And the peripheral wall sections of the tunnel portion having a certain length are sequentially connected in a step-like manner.

Here, the magnitude of the cutting angle of the drilling machine 4 of the drilling apparatus according to the embodiment of the present invention and the cutting angle of the conventional drilling machine D will be compared and studied with reference to FIGS.
Now, in the case of drilling holes of the same depth (length), if the length of the rod body C of the conventional example shown in FIG. The length of the rod body 7 is 2L or more, but the length is 2L.
When the respective cutting angles are obtained, the cutting angle α = arctan (h / L) in the conventional drilling device, and the cutting angle β = arctan (h / L) in the drilling device of the embodiment of the present invention.
2L) ≒ 1/2 × arctan (h / L) = α / 2.
In addition, h is the height of the vertical wall part of the tunnel peripheral wall surface excavated by the conventional apparatus.

That is, according to the apparatus of the embodiment of the present invention, drilling for tunnel excavation can be performed at about 1/2 of the insertion angle of the conventional drilling apparatus, and the height of the vertical wall 13 of the tunnel is also reduced. It can be halved.

[0014]

As described above, according to the drilling device for the outer peripheral portion of the tunnel face of the present invention, the length of the hole for drilling the rod body of the drilling machine with the bit attached to the tip is at least twice the depth of the hole. Therefore, the tunnel can be pierced from the outer periphery of the face of the planned tunnel to the same depth in the length direction of the tunnel with a smaller angle than the conventional piercing device. When drilling, the above-mentioned hole can minimize the step of the tunnel peripheral wall that becomes step-shaped in cross section, and the amount of concrete used during concrete lining is reduced, making it possible to perform economical and efficient construction It becomes.

[Brief description of the drawings]

FIG. 1 is a side view of a punching device,

FIG. 2 is a simplified longitudinal side view showing a perforated state;

FIG. 3 is a simplified vertical sectional side view showing a state of piercing by a conventional piercing device.

[Explanation of symbols]

 1 cart 3 guide stand 4 drilling machine 7 rod body 7a bit 10 face face 11 holes

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Jiro Okamura 2-2-2 Matsuzakicho, Abeno-ku, Osaka-shi Okumura Gumi Co., Ltd. (72) Takamitsu Makita 2-2-2 Matsuzakicho, Abeno-ku, Osaka Shares Company Okumura Gumi (58) Field surveyed (Int.Cl. ⁶ , DB name) E21C 9/00 E21D 9/00

Claims (1)

(57) [Claims] 1. A guide table is provided on a traveling vehicle, and a drilling machine having a rod body with a bit attached to a tip is mounted on the guide table so as to be movable back and forth, and the drilling machine is advanced by moving the drilling machine forward. In a drilling device configured to drill a hole of a certain depth in the tunnel length direction on a surface, the rod body is formed to be twice or more the depth of the hole to be drilled. A perforation device at the periphery of the tunnel face.