JP2012167427A - Bedrock drilling device and bedrock drilling method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bedrock drilling device and a bedrock drilling method, suitable for drilling downward extending holes in a bedrock while partly overlapping each other.SOLUTION: In the state that a guide rod 20 is inserted into an already drilled second hole 24B, a closing member 30 is inserted into an already drilled first hole 24A adjacent to the second hole 24B to close a communication area between the first hole 24A and the second hole 24B over the total length of the first hole 24A. The closing member 30 prevents cuttings formed when drilling a third hole 24C adjacent to the second hole 24B from entering into a slit groove including the first hole 24A through an annular gap 26 between the outer periphery of the guide rod 20 and the inner wall of the second hole 24B.

Description

  The present invention relates to a rock drilling device and a rock drilling method used for blast-free excavation, and more specifically, in tunnel excavation, a large number of holes extending downward are dug in the rock while overlapping some of them. The present invention relates to a rock drilling device and a rock drilling method suitable for forming slit-shaped grooves.

Conventionally, when excavating a tunnel by blastless excavation, first, as shown in FIG. 4, a large number of holes are formed by a rock drilling device along the outer periphery of the cross section of the tunnel and along a plurality of regions defining the cross section. Are partly overlapped and continuously drilled, and a slit-like groove 12 is formed by a plurality of rows of holes.
Next, a large number of split rock holes 14 are drilled in a region surrounded by the slit-shaped grooves 12 by a rock drilling device, and a split rock machine is inserted into each split rock hole 14 to expand the split rock holes 14. Let At this time, since the slit-shaped groove 12 functions as a free surface on which nothing exists, the wall surface of the region surrounded by the slit-shaped groove 12 is collapsed by the expansion of a large number of split rock holes 14. In this way, the tunnel is excavated.

The rock drilling device has a rotating rod with a drilling bit attached to the tip, and the drilling bit is rotated by this rotating rod so that water is poured into the hole. Holes are drilled while being supplied, and milled powder such as crushed stones and earth and sand are discharged outside the drilled holes.
On the other hand, in order to form the slit-shaped groove 12, it is necessary to drill while overlapping a part of the holes, and when trying to drill with a drill bit so that a part of the holes overlaps, Since it is attached to the tip of the rotating rod, it tends to displace to the already drilled hole side with low resistance.
Therefore, a guide rod to be inserted into a hole that has already been drilled is provided adjacent to the rotating rod, and the drill bit is brought into contact with the rotating rod to suppress the displacement of the drill bit, and a number of holes are assigned to one of them. We can excavate while overlapping the parts.

The present applicant has proposed a rock drilling device in which the outer peripheral portion of such a guide rod is configured to be rotatable and the drilling efficiency by the drilling bit is remarkably improved (Patent Documents 1 to 5).
A drilling process using this rock drilling device is shown in FIG.
In FIG. 5, a drill bit 18 is attached to the tip of the rotary rod 16, and the rotary rod 16 and the guide rod 20 are supported by a bracket 22A at the tip of the base 22 of the rock drilling device.
First, after the first hole 24A, which is the first hole, is drilled by the drill bit 18, the guide rod 20 is inserted into the first hole 24A, as shown in FIGS. Then, the second hole 24B partially overlapping the first hole 24A is excavated by the drill bit 18. At this time, the drilling bid 18 to be displaced toward the first hole 24A that has already been drilled is brought into contact with the rotatable outer peripheral portion of the guide rod 20 to suppress the displacement, and the first hole 24A. The second hole 24B parallel to the first hole 24A is partially drilled by the drill bit 18 while partially overlapping the first hole 24A.
FIG. 6 shows a plan view when the slit-shaped groove 12 is formed by excavating a large number of such hole holes.

Japanese Patent No. 3477683 Japanese Patent No. 3479754 Japanese Patent No. 3,496,857 Japanese Patent No. 3748288 Japanese Patent No. 3748291

By the way, for example, when excavating the bedrock vertically for the construction of a shaft in the suburbs of the city, or when excavating the tunnel cross section downward from the middle of the tunnel construction, The slit-shaped groove 12 must also be drilled downward.
This drilling process is shown in FIGS.
As shown in FIGS. 7A to 7C, the first hole 24A is drilled by the drill bit 18, and the guide rod 20 is inserted into the first hole 24A to cut the second hole 24B. Until the holes are formed, the milled crushed stones and earth and sand are discharged to the outside of the holes by the water injected at the time of cutting, so there is no problem. That is, the second hole 24B in the middle of the drilling is in communication with the annular gap 26 between the outer periphery of the guide rod 20 and the inner wall of the second hole 24B, and the outer periphery of the guide rod 20 is the drilling hole. Although being rotated by the bit 18, the flour is returned to the original third hole 24 </ b> C around the annular gap 26 by the outer peripheral portion of the guide rod 20, and discharged to the outside of the third hole 24 </ b> C by water. Because.
However, as shown in FIG. 7D, the following problems occur after the step of inserting the guide rod 20 into the second hole 24B and drilling the third hole 24C.

That is, when the third hole 24C for forming the slit-shaped groove 12 is drilled downward while partially overlapping the second hole 24B, the third hole 24C in the middle of the drilling is formed in the guide rod 20. Communicated with the annular gap 26 between the outer periphery of the second hole 24B and the inner wall of the second hole 24B, and also communicated with the first hole 24A, which is a large space, via the annular gap 26, and The hole 24A is deeper than the third hole 24C in the middle of drilling. In addition, milled powder such as crushed stone and earth and sand has a large specific gravity.
Therefore, when the third hole 24C is drilled while injecting water, the ground powder such as crushed stone and earth and sand is guided to the annular gap 26 by the outer periphery of the rotating guide rod 20 and 1 in the first hole 24A and deposited in the first hole 24A or deposited in the slit-like groove 12 connected to the first hole 24A. Keeps increasing with each drilling.
For this reason, even if a large number of split rock holes 14 are drilled in the region surrounded by the slit-shaped grooves 12 and a split rock machine is inserted into each split rock hole 14 to expand each split rock hole 14, Since the powder is deposited on the bottom of the slit-like groove 12, the slit-like groove 12 is unlikely to function as a free surface, and the wall surface is not easily broken by the split rock machine, and the tunnel excavation efficiency is reduced.
The present invention has been devised in view of the above circumstances, and an object of the present invention is to provide a rock drilling device and a rock drilling suitable for drilling while partially overlapping a hole extending downward in the rock. It is to provide a hole method.

In order to achieve the above object, the present invention includes a gantry, a rotating rod that is supported by the gantry so as to be rotatable and movable in the axial direction thereof, and a rotary rod having a drilling bit attached to the tip thereof. A driving means and an outer peripheral portion that is supported by the frame and extends in parallel with the rotating rod, is inserted into a hole that has already been drilled by the drilling bit, is in contact with the drilling bit, and is rotatable. And rock drilling provided with a guide rod for suppressing the displacement of the drilling bit by contact with the drilling bit and sequentially drilling the hole while overlapping the already drilled hole. In the hole device, the guide rod extends along the guide rod adjacent to a position of the guide rod that is supported by the gantry and is positioned opposite to the rotating rod, and the guide rod is already drilled into the second hole. Inserted, previous It is inserted into the first hole already drilled adjacent the second hole, wherein the closing member for closing the communicating portion of the first hole and the second hole.
In the rock drilling method of the present invention, the guide rod is inserted into a hole that has already been drilled and extends downward, and the outer periphery of the guide rod that can be rotated by the drill bit attached to the tip of the rotary rod. While making contact with the portion, and discharging the cut flour to the outside of the hole with water, a number of holes that overlap and partially extend downward are drilled to form slit-like grooves in the rock When the guide rod is inserted into the already drilled second hole, the closing member is inserted into the already drilled first hole adjacent to the second hole. Then, the communication portion of the first hole and the second hole is closed over the entire length of the first hole, and the dusting at the time of drilling is caused by the outer periphery of the guide rod and the inner wall of the second hole. The blocking member prevents entry into the slit-like groove including the first hole through the annular gap between One, characterized in that to perform the boring of the third hole adjacent to the second hole.

According to the rock drilling apparatus and the rock drilling method of the present invention, when the third hole is drilled, the communication portion between the second hole and the first hole is closed by the closing member, and the annular gap and the large space are formed. Communication with the first hole is blocked.
Accordingly, the dusting at the time of drilling the third hole is guided to the annular gap by the outer peripheral portion of the rotating guide rod, flows into the first hole from the annular gap, and accumulates in the first hole. Can be eliminated.
Therefore, if a number of holes for split rocks are drilled in the area surrounded by slit-shaped grooves and a split rock machine is inserted into each hole for split rocks to expand each hole for split rocks, the slit-shaped grooves will be Since it functions as a free surface, the wall can be crushed by a split rock machine, and the excavation efficiency when drilling the tunnel vertically can be improved by blast-free excavation using the split rock machine.

It is explanatory drawing at the time of excavating a hole vertically with the rock drilling device which has a guide rod and a closure member. It is a top view which shows the state which excavates a hole vertically by the rock drilling apparatus which has a guide rod and a closure member. It is a top view which shows the state which drills many holes with the rock drilling apparatus which has a guide rod and a closure member, and forms a slit-shaped groove | channel. It is explanatory drawing at the time of breaking a wall surface when excavating a tunnel in a horizontal direction. It is explanatory drawing at the time of excavating a hole horizontally by the rock drilling apparatus which has a guide rod. It is a top view which shows the state which drills many holes using a drill bit and a guide rod, and forms a slit-shaped groove | channel. It is explanatory drawing at the time of excavating a hole vertically with the rock drilling apparatus which has a guide rod.

Hereinafter, embodiments of the present invention will be described with reference to FIGS. In addition, the same code | symbol is attached | subjected and demonstrated to the member and location similar to the conventional member and location.
As shown in FIGS. 1 to 3, the rock drilling device includes a gantry 22, a rotating rod 16 having a drilling bit 18 attached to the tip, a rotation driving means and an axial movement of the rotating rod 16 (not shown). Means, a guide rod 20 and a closing member 30 are included.
In the present embodiment, the drilling bit 18 first drills the first hole 24A, and then inserts the guide rod 20 into the first hole 24A to drill the second hole 24B. Next, the closing member 30 is inserted into the first hole 24A, and the guide rod 20 is inserted into the second hole 24B, whereby the third hole 24C is drilled.
The gantry 22 extends in the vertical direction, and a bracket 22A is attached to the lower end.
The rotating rod 16 extends in the vertical direction, and is supported by the gantry 22 via a bearing and a bracket 22A so as to be rotatable and movable in the axial direction.
The rotation driving means and the axial movement means are supported by the gantry 22 and move downward while rotating the rotating rod 16 during drilling.

When the guide rod 20 is continuously drilled by partially overlapping holes to form the slit-shaped groove 12, the drill bit 18 is already drilled with low resistance. The displacement to the hole side is suppressed.
The guide rod 20 can be inserted into a hole that has already been drilled by the drill bit 18 and has a length that reaches the bottom of the hole.
The guide rod 20 includes an inner member supported by the gantry 22 and a cylindrical outer member that is rotatably supported by the inner member and covers the entire area of the inner member below the gantry 22, and is parallel to the rotating rod 16. And it extends up and down. The outer member constitutes a rotatable outer peripheral portion of the guide rod 20, and the outer member rotates when the drilling bit 18 that is rotationally driven contacts, and the outer member is made of steel.
In addition, the code | symbol 32 has shown the contact member which stabilizes the attitude | position of the mount frame 22 by contact | abutting to a rock.

The blocking member 30 is inserted into the already drilled first hole 24A adjacent to the second hole 24B in a state where the guide rod 20 is inserted into the already drilled second hole 24B at the time of drilling. The communication portion 2402 (see FIGS. 2 and 3) between the first hole 24A and the second hole 24B is closed.
The closing member 30 is supported by the gantry 22 via the bracket 22A. The closing member 30 is provided adjacent to the position of the guide rod 20 positioned opposite to the rotating rod 16, extends along the guide rod 20, and has a length corresponding to the entire length of the guide rod 20. .
The closing member 30 may be made of steel, may be made of a synthetic resin, or may be made of rubber. In short, the communication portion between the first hole 24A and the second hole 24B. Any material may be used as long as it can block 2402, and the material constituting the blocking member 30 is not particularly limited.
Further, the cross-sectional shape of the closing member 30 is not particularly limited as long as it closes the communication portion 2402 of the first hole 24A and the second hole 24B.

In the present embodiment, the closing member 30 includes an inner member 30A and an outer member 30B that covers the inner member 30A.
The inner member 30 </ b> A is made of a rigid material in a rod shape, is made of steel or synthetic resin, and is supported by the gantry 22.
The outer member 30B is formed of various conventionally known elastically deformable materials such as rubber.
In the present embodiment, since the closing member 30 is inserted into and removed from the drilled hole, the outer member 30B is made of hard rubber having a Shore-A hardness of 60 to 80, and the durability of the closing member 30 is increased. I am doing so.
Further, the outer member 30B is an ellipse whose cross-sectional shape cut in a direction orthogonal to the extending direction has a major axis in a direction orthogonal to the direction in which the rotating rod 16, the guide rod 20, and the closing member 30 are arranged. It is shaped.

When the outer member 30B is inserted into the already drilled first hole 24A, the outer member 30B comes into contact with the bottom of the first hole 24A and is sandwiched between the bracket 22A of the gantry 22 and the bottom of the first hole 24A. The length of the gantry 22 from the bracket 22A is larger than the dimension from the bracket 22A to the bottom of the first hole 24A so that the first hole 24A extends outward in the radial direction.
The inner member 30A has a cross-sectional area and a length that prevent the outer member 30B from bending in a direction orthogonal to the longitudinal direction of the outer member 30B when the outer member 30B is sandwiched between the gantry 22 and the bottom of the first hole 24A. For example, the length of the gantry 22 from the bracket 22 </ b> A is formed to extend to a location near the lower end of the guide rod 20.

Next, a rock drilling method for forming a slit-like groove 12 vertically below using a rock drilling device will be described.
For example, when excavating a bedrock vertically for the construction of a shaft in the suburbs of the city, or when excavating a tunnel cross section downward from the middle of tunnel construction, along the outer periphery of the cross section of the tunnel to be excavated, A plurality of holes directed downward are partially overlapped and continuously drilled along a plurality of regions, and a slit-like groove 12 is formed by a row of the plurality of holes.
More specifically, when forming the slit-like groove 12, first, the first hole 24 </ b> A is drilled by the drill bit 18 while water is injected from the lower end of the drill bit 18. In this case, drilling is performed while discharging the milled powder such as crushed stone and earth and sand to the outside of the first hole 24A with water.

  Next, as shown in FIGS. 7A to 7C, the guide rod 20 is inserted into the first hole 24A that has already been drilled up to the bottom of the first hole 24A. While making the drill bit 18 in contact with the guide rod 20 and discharging the ground powder such as crushed stone and earth and sand to the outside of the hole with water, a part of the first hole 24A already drilled and a part thereof The overlapped second hole 24B is drilled. In this case, since the outer member 30B of the guide rod 20 is rotated by the drill bit 18, the flour is guided by the outer member 30B and guided to the annular gap 26. Is returned to the first hole 24A. Further, since the annular gap 26 is closed, the amount of dusting remaining in the annular gap 26 is small after the second hole 24B is drilled.

Next, as shown in FIG. 1, when the third hole 24C partially overlapped with the second hole 24B is drilled, the guide rod 20 is formed in the second hole 24B over the entire length of the second hole 24B. And the closing member 30 is inserted into the first hole 24A over the entire length of the first hole 24A. By inserting the closing member 30 into the first hole 24A, the communication portion 2402 of the first hole 24A and the second hole 24B is closed over the entire length of the first hole 24A.
Then, the second drill hole 24B is brought into contact with the guide rod 20 by the drill bit 18 and while discharging the ground powder such as crushed stone and earth and sand with water to the outside of the hole. The third hole 24C partially overlapped with is drilled.

In this case, the third hole 24C in the middle of the drilling is communicated with the annular gap 26 between the outer periphery of the guide rod 20 and the inner wall of the second hole 24B, but the second hole 24B is closed by the closing member 30. The communication portion 2402 of the first hole 24A is closed, and communication between the annular gap 26 and the first hole 24A that is a large space is blocked.
Therefore, since the outer member 30B of the guide rod 20 is rotated by the drill bit 18, the flour is guided by the outer member 30B and guided to the annular gap 26. 24C and the annular gap 26 is closed, so that the amount of dusting remaining in the annular gap 26 is small after the third hole 24C is drilled.
Then, such a drilling operation is continuously performed, and as shown in FIG. 3, the slit-like groove 12 is horizontally formed from a large number of the drilling holes 24A, 24B, 24C,. It is formed extending in the direction.

Therefore, according to the present embodiment, the dusting at the time of drilling is guided to the annular gap 26 by the outer peripheral portion of the rotating guide rod 20, flows from the annular gap 26 into the first hole 24A, and enters the first hole 24A. It is possible to solve the problem of being accumulated in the hole 24A or being accumulated in the slit-like groove 12 connected to the first hole 24A.
Therefore, if a large number of split rock holes 14 are drilled in the area surrounded by the slit-shaped grooves 12 and a split rock machine is inserted into each split rock hole 14 to expand each split rock hole 14, slits Since the groove-shaped groove 12 functions as a free surface, the wall can be efficiently broken by a split rock machine, which is advantageous in increasing the excavation efficiency of the tunnel downward by blastless excavation using the split rock machine. .

In the present embodiment, the outer member 30B is formed of an elastically deformable material, and when inserted into the first hole 24A, the outer member 30B expands outward in the radial direction of the first hole 24A.
Therefore, the closing member 30 can more reliably close the communication portion 2402 of the second hole 24B and the first hole 24A, and is advantageous in preventing accumulation of dusting into the slit-like groove 12 during drilling. Thus, the slit-shaped groove 12 can function as a free surface, and the area partitioned by the slit-shaped groove 12 can be efficiently broken using a rock drill, and tunnel excavation work downward by blast-break excavation This is more advantageous for increasing efficiency.
In the present embodiment, since the cross-sectional shape of the outer member 30B cut in the direction orthogonal to the extending direction is an ellipse, the first member 24B is inserted into the first hole 24A when the first member 24B is inserted into the first hole 24A. A large area can be secured for the outer member 30B to contact the wall surface of the first hole 24A near the communication portion 2402 between the hole 24A and the second hole 24B, and the communication portion 2402 between the second hole 24B and the first hole 24A. This is advantageous for more reliable blockage, and allows the slit-shaped groove 12 to function as a free surface, and the area partitioned by the slit-shaped groove 12 can be efficiently broken down using a rock drill, and blast-free excavation is possible. It will be more advantageous in improving the excavation construction efficiency of the tunnel by downward.

Further, since the outer member 30B has an oval outline and is smaller than the circle forming the outline of the first hole 24A, the insertion / removal of the closing member 30 to / from the first hole 24A can be performed smoothly, and tunnel excavation efficiency is improved. It is advantageous also in raising.
Further, since the outer member 30B is made of hard rubber, it is advantageous in improving the durability of the closing member 30 inserted into and removed from the drilled hole, and reducing the cost spent for tunnel excavation work downward. .

12... Slit-shaped groove 16... Rotating rod 18 .. drilling bit 20 .. guide rod 22 .. mount 24A, 24B, 24C .. first, second and third holes 26. …… Closing member 30A …… Inner member 30B …… Outer member

Claims (6)

A frame,
A rotating rod which is supported by the frame so as to be rotatable and movable in the axial direction, and a drill bit is attached to the tip;
A rotation drive means for rotating the rotation rod;
The drilling hole having an outer peripheral portion that is supported by the pedestal and extends in parallel with the rotating rod and is inserted into a hole that has already been drilled by the drilling bit so as to be able to contact and rotate with the drilling bit. A guide rod for sequentially drilling holes while suppressing a displacement of the drilling bit by contacting the bit and overlapping a part of the already drilled hole;
In rock drilling equipment equipped with
A state where the guide rod extends along the guide rod adjacent to the position of the guide rod which is supported by the gantry and is positioned opposite to the rotating rod, and the guide rod is inserted into the already drilled second hole. Then, a closing member is provided which is inserted into the already drilled first hole adjacent to the second hole and closes the communication portion of the first hole and the second hole.
Rock drilling device characterized by that. The closing member is composed of an inner member formed of a rigid material and supported by the gantry, and an outer member formed of an elastically deformable material and covering the inner member,
When the outer member is inserted into the already drilled first hole, the outer member comes into contact with the bottom of the first hole and is sandwiched between the gantry and the bottom of the first hole. Is formed with a dimension larger than the dimension from the gantry to the bottom of the first hole so as to spread outward in the radial direction of
The inner member is formed with a cross-sectional area and a length that prevent the outer member from bending in a direction perpendicular to the longitudinal direction of the outer member when the outer member is sandwiched between the gantry and the bottom of the first hole. ing,
The rock drilling device according to claim 1. The outer member has an elliptical shape in which a cross-sectional shape cut in a direction orthogonal to the extending direction has a long axis in a direction orthogonal to the direction in which the rotating rod, the guide rod, and the blocking member are arranged. ing,
The rock drilling device according to claim 1 or 2, characterized in that. The outer member is formed of a hard rubber having a Shore-A hardness of 60 to 80,
The rock drilling device according to any one of claims 1 to 3, wherein the rock drilling device is provided. The guide rod was inserted into a hole that had already been drilled and extended downward, and was cut while being in contact with the rotatable outer periphery of the guide rod by a drill bit attached to the tip of the rotating rod. While discharging the dust from the hole with water, when forming a slit-like groove in the rock mass by drilling a number of holes that overlap and partially extend downward,
With the guide rod inserted into the already drilled second hole, the closing member is inserted into the already drilled first hole adjacent to the second hole. Blocking the communication portion of the first hole and the second hole over the entire length of the hole,
The closing member prevents dusting during drilling from entering the slit-like groove including the first hole through an annular gap between the outer periphery of the guide rod and the inner wall of the second hole. While blocking, the third hole adjacent to the second hole was drilled.
A rock drilling method characterized by that. A gantry for supporting the rotating rod, the guide rod, and the closing member is provided,
The closing member is composed of an inner member formed of a rigid material and supported by the gantry, and an outer member formed of an elastically deformable material and covering the inner member,
When the closing member is inserted into the first hole, the outer member is sandwiched between the gantry and the bottom of the first hole and spread outward in the radial direction of the first hole.
The rock drilling method according to claim 5, wherein:

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