JPH07197766A - Drilling device for external surface of tunnel facing plane - Google Patents

Abstract

PURPOSE:To reduce an insertion angle for a drilling machine rod body having a bit mounted on the forward end thereof, when a hole of constant depth is drilled around the external surface of the facing plane of a tunnel in the lengthwise direction thereof. CONSTITUTION:A drilling machine 4 is installed in such a state as freely movable back and forth on a guide seat 3 laid on a travel carriage 1 so as to be capable of freely slewing and turning vertically and right and left. The length of the drilling rod body 7 of the machine 4 is made equal to or two times the depth of a hole 11 to be drilled, thereby reducing the insertion angle of the rod body 7 and excavating a tunnel having the predetermined cross sectional form.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a boring device for boring a tunnel face with a predetermined depth along the outer circumference of a planned tunnel in the length direction of the tunnel along the outer circumference of the planned tunnel. is there.

[0002]

2. Description of the Related Art When excavating a tunnel by a blasting method, first, holes or slots having a predetermined depth are formed at appropriate intervals along the outer circumference of a planned tunnel and surrounded by the holes or slots. BACKGROUND ART A large number of blast holes are bored in a facet, and then a tunnel portion having a predetermined length is excavated by charging the blast holes and blasting.
As such a piercing device, as shown in FIG. 3, a piercing machine D having a rod body C with a bit B attached to its tip is moved back and forth on a guide base A that is rotatable in the vertical and horizontal directions. There is known a device that is freely mounted and configured to advance a punching machine D while rotating and striking a rod body C to punch a rod with a tip bit B.

When the hole E is bored along the outer circumference of the planned tunnel by the punching device constructed as described above, the upper half of the body of the punching machine D projects upward from the axis of the rod body C. The projecting portion abuts on the peripheral wall surface F of the already excavated tunnel portion, and a horizontal hole cannot be bored 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 punching machine D is slanted outward as it approaches the tip, that is, the rod body C is set to a predetermined insertion angle (piercing angle), and is set in this state. The drilling work is sequentially performed so that the tunnel wall surface has a stepwise cross section in the tunnel length direction.

[0004]

However, in the above-described conventional punching device, the length of the rod body C is to be the hole E to be bored.
Since the hole E is formed to have a dimension substantially equal to the depth of the hole E, when the hole E is drilled to a predetermined depth, the drilling machine D reaches a portion near the face of the face, and therefore a relatively large cutting angle is required in order. There is a problem that the step difference of the hole E to be drilled becomes large and the lining concrete constructed after excavation becomes unnecessarily thick and uneconomical. An object of the present invention is to provide a drilling device for the outer peripheral portion of the tunnel face, which can reduce the insertion angle of the drilling rod body of the drilling machine as much as possible.

[0005]

In order to achieve the above-mentioned object, in the punching device for the outer peripheral portion of the tunnel face of the present invention, a guide base is arranged on a traveling carriage, and a bit is provided at the tip on the guide base. In a punching device configured to mount a drilling machine having a mounted rod body so as to be movable back and forth, and to form a hole having a constant depth in a tunnel length direction on a face by moving the drilling machine forward, It is characterized in that the rod body is formed to have a length that is at least twice the depth of the hole to be bored.

[0006]

When the boring machine of the boring device punches from the outer peripheral portion of the tunnel face in the length direction of the tunnel, when the tip bit of the rod body is brought into contact with the outer peripheral portion of the face face, Has a length more than twice the depth of the hole to be drilled, the machine body of the drilling machine is located farther from the face of the face as compared with the conventional device, and from this state, the predetermined depth is reached. Even if the hole is drilled, the drilling machine 4 drills first,
Only the second or more walls of the stepped peripheral wall of the formed tunnel portion can be reached. Therefore, even if the cutting angle is made small, the tunnel length portion with a constant cross-section is sequentially excavated and formed. It is possible.

[0007]

Embodiments of the present invention will now be described with reference to the drawings.
Reference numeral 1 denotes a cart which is driven by a caterpillar, and a boom 2 is pivotally attached to a front end surface of the cart so as to be vertically and horizontally rotatable. It is freely connected. The turning of the boom 2 with respect to the traveling carriage 1 and the rotation of the guide base 3 with respect to the boom 2 are performed by a hydraulic jack.
The length of the guide base 3 is longer than that of the conventional guide base by a dimension substantially equal to the depth (length) of the hole to be drilled.

Reference numeral 4 denotes a punching machine, which is integrally mounted on a pedestal 5 slidably arranged in the front-rear direction on the guide base 3, and is provided on a rear end portion of the guide base 3 with a hydraulic cylinder ( It is moved back and forth by (not shown). The punching machine 4 rotatably supports a rear end portion of a rod body 7 which is rotated and hit by a drifter 6 on an upper surface of a front end of the pedestal 5 so that the rod body 7 is moved forward in a longitudinal direction of the guide base 3. The rod 7 is slidably inserted into the bearing 8 provided on the upper surface of the front end of the guide base 3, and the bit 7a is detachably attached to the front end of the rod body 7. The length of the rod body 7 is twice or more the depth of the hole to be drilled. The reference numeral 9 designates a guide base fixing device arranged on the lower surface side of the front end of the guide base 3.

In order to form a hole 11 having a constant depth in the tunnel length direction on the outer peripheral portion of the tunnel facet 10 by the perforating device constructed as described above, first, the gantry 5 is retracted and placed on the gantry 5. The punching machine 4 is located at the rear part of the guide table 3,
In this state, the traveling carriage 1 is moved to the vicinity of the face face 10, and the boom 2 and the guide base 3 are turned and rotated to orient the length direction of the rod body 7 of the punching machine 4 in the drilling direction. At the same time, a predetermined insertion angle is set, and the fixing tool 9 is pressure-bonded to the outer peripheral portion of the face face 10 to fix the guide base 3.

After that, while rotating and striking the rod body 7 of the punching machine 4, the gantry 5 is moved forward by a hydraulic jack and, as shown in FIG. 2, at a predetermined insertion angle and at a predetermined depth in the tunnel length direction. The hole 11 is formed. At this time, since the length of the rod body 7 is formed to be twice or more the depth of the hole 11, even if the hole 11 is drilled to a predetermined depth, the position of the punching machine 4 is already excavated. After the second step of the stepped peripheral wall section of the formed tunnel section, it reaches only to the position located rearward from the face face 10. Then, after drilling this hole 11,
The rod body 7 is pulled out and the outer peripheral portion of the next face having a desired distance from the hole 11 is similarly perforated, and this operation is repeated to provide a large number of holes 11 along the outer periphery of the face 10.

Further, as is well known, the holes 11 are formed in the face face 10.
After making a large number of holes with almost the same depth as those in the tunnel length direction and loading explosives into these holes to explode them, or inserting a tubular expander into the holes to expand them A crack is generated in the rock mass between the holes, and a tunnel portion corresponding to the depth of the hole is excavated and formed. When the 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 forms 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. , The vertical wall portion 13 extending from the rear end of the peripheral wall portion 12 in the tunnel radial direction
The cross section of the peripheral wall of the tunnel portion having a certain length is sequentially connected in a stepwise manner.

Here, the magnitudes of the cutting angle of the punching machine 4 of the punching apparatus and the cutting angle of the conventional punching machine D in the embodiment of the present invention will be compared and examined with reference to FIGS. 2 and 3.
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. 3 is made equal to the drilling distance L, the drilling machine of the embodiment of the present invention. The length of the rod body 7 of 4 is 2L or more, but the length is 2L.
As to the respective cutting angles, 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 present invention.
2L) ≈1 / 2 × arctan (h / L) = α / 2.
Note that h is the height of the vertical wall portion of the peripheral wall surface of the tunnel excavated by the conventional device.

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

[0014]

As described above, according to the punching device for the outer peripheral portion of the tunnel face according to the present invention, the length of the hole is not less than twice the depth of the hole for drilling the rod body of the drilling machine with the bit mounted at the tip. Since it is formed in the height of the tunnel, it is possible to drill from the outer peripheral portion of the face face of the planned tunnel to the same depth in the tunnel length direction with a small angle of insertion compared to the conventional drilling device. When excavating, the step can be set to a minimum at the tunnel peripheral wall that has a stepped cross section when excavating, the amount of concrete used during concrete lining can be reduced, and economical and efficient construction is possible. It will be.

[Brief description of drawings]

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

FIG. 2 is a simplified vertical sectional side view showing a punched state,

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

[Explanation of symbols]

 1 bogie 3 guide stand 4 punching machine 7 rod body 7a bit 10 face 11 holes

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Hiroaki Muranaka, 2-2-2 Matsuzaki-cho, Abeno-ku, Osaka-shi Okumura-gumi, Inc. (72) Inventor Jiro Okamura 2--2, Matsuzaki-cho, Abeno-ku, Osaka No. Stock Company Okumura Group (72) Inventor Takamitsu Makita 2-2-2 Matsuzaki-cho, Abeno-ku, Osaka City Company Limited Okumura Group

Claims (1)

[Claims] 1. A guide platform is provided on a traveling carriage, and a perforator having a rod body having a bit attached to its tip is mounted on the guide platform so as to be movable back and forth, and the face is advanced by advancing the perforator. In a drilling device configured to drill a hole of a certain depth in a tunnel length direction on a surface thereof, the rod body is formed to have a length that is at least twice the depth of the hole to be drilled. A punching device for the outer peripheral part of the tunnel face.