JPH07167596A - Blasting method of rocks or the like - Google Patents

Abstract

PURPOSE:To blow up with accuracy, and hence enhance work efficiency by generating cracks definitely along a planning blasting line when blowing up rocks or the like to be blasted based on a blasting method. CONSTITUTION:A blasting hole 2 oval in cross section, is bored along an outer peripheral edge of a planning excavation part of an article 1 to be blasted in such a state that longer-side ends be opposed to each other with a definite spacing while void holes 4 are bored in the middle part between adjacent blasting holes 2. An explosive 7 is loaded in each of the blasting holes 2 and blasted, thereby concentrating the blasting force in the shorter-side direction of the blasting holes 2, and particularly generating cracks at the void holes 4 so that each adjacent blasting hole 2 may be connected to each other by way of the cracks and the void holes 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blasting method for crushing rock mass, or crushed material such as residual iron or concrete of a blast furnace by blasting.

[0002]

2. Description of the Related Art Conventionally, in order to crush an object to be crushed, such as bedrock, by a blasting method, blasting holes having a circular cross section with a predetermined depth are formed at appropriate intervals at a portion to be crushed. The blasting method is adopted in which cracks are generated in all directions from each blasting hole by loading the inside with explosives and then blasting. Furthermore, in such a blasting method, since the crack direction from the blast hole is indefinite and efficient crushing cannot be expected, a notch is formed on the wall surface of the blast hole to cause stress concentration in the notch portion during blasting. It is also practiced to determine the crack direction.

[0003]

However, the notch is formed by the blade at the same time when the notch is formed by using a perforating rod having a notch forming blade protruding from the outer peripheral surface thereof. Not only is it troublesome to perform the installation work, but, for example, when rock is drilled, the hole wall to be excavated by the rod tip bit becomes an uneven surface, so that it follows this bit and integrally enters in the length direction of the rod. Even if it is possible to form a notch in the convex surface of the hole wall by the blade body, there are cases where the notch cannot be formed in the concave surface, and
Since the correction cannot be performed, the notch is formed discontinuously in the length direction of the blast hole, and the depth thereof is also nonuniform, which makes it impossible to generate an accurate crack. An object of the present invention is to provide a blasting method capable of completely eliminating such problems.

[0004]

In order to achieve the above object, the blasting method according to the first aspect of the present invention is such that blasting holes having a cross-section elongated hole shape are formed in a crushed object such as bedrock at predetermined intervals. After drilling to the desired depth with the long side edges of the adjacent blast holes facing each other and forming holes between the adjacent blast holes, the blast holes have a longitudinal direction at the center in the width direction. It is characterized by loading a long and narrow explosive into the blast hole, filling a filling in the blast hole, and then blasting.

In the blasting method according to the second aspect of the present invention, blasting holes having a cross-section elongated hole shape are formed at a predetermined interval in an object to be crushed such as bedrock, and the blasting holes are arranged on the long side of the blasting holes. It is characterized in that a hole is provided in the vicinity of the blast hole, a long explosive is loaded in the depth direction of the blast hole in the direction of the long side of the cross section of the blast hole, and the blast hole is filled with a filling material before blasting. Is.

[0006]

According to the invention described in claim 1, when explosives are loaded into the blasting hole having a long hole-shaped cross section to explode, the crushing force is concentrated in the short side direction of the hole to act and the long diameter is obtained. A crack will occur in the extension direction. Then, since a plurality of blast holes are formed in the crushed object at regular intervals with their long side ends facing each other, cracks are surely generated between adjacent blast holes. In addition, since the holes are provided between the adjacent blast holes, the cracks communicate with the holes, and the gas generated during the blast is discharged to the outside through the holes. Furthermore, since all the blast holes are continuous due to cracks through the holes, not only can the number of blast holes drilled and the amount of explosive used be reduced, but also accurate drilling along the outer edge of the planned excavation surface can be achieved. Is possible.

Further, according to the second aspect of the invention, since the explosive having a long cross section is loaded with the explosive which is long in the cross sectional long side direction, the explosive force of the explosive explodes. The holes are concentrated at the ends in the direction of the long side of the cross section, and cracks are surely generated from the ends toward the adjacent blast holes and holes which are weak bodies. Therefore, between the blast holes and between both ends of the blast hole and between both ends of the holes are continuous by a crack, and the crushed material portion surrounded by the crack can be efficiently excavated and removed.

[0008]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 shows a method of excavating a tunnel in rock as the crushed object 1 by the blasting method of the present invention, in which the ends in the major axis direction are opposed to each other at regular intervals along the outer peripheral edge of the excavated surface of the planned tunnel. The first blast hole row A is formed by piercing the blast holes 2 having a cross-sectional shape in this state, and at the same time, the arch-shaped second blast hole row is inwardly spaced from the first blast hole row A at regular intervals. B, a third blast hole array C is drilled, and further,
A bore hole 3 having a vertically elongated cross section is bored in the central portion of the crushed portion surrounded by the innermost third blast hole row C to a depth substantially equal to that of the blast hole 2 and the bore hole. On both sides of the borehole 3, the length of the borehole 3 is one side.
Blasting holes 2a, 2a are formed in the length direction of.

Further, in the first blast hole row A, a small-diameter hole 4 having a circular cross section is bored in the intermediate portion between the adjacent blast holes 2 to a depth substantially the same as that of the blast holes 2. That is, the blast holes 2 and the holes 4 are alternately bored. Also, blast hole 2
The hole is formed such that the distance between the end of the blast hole 2 and the hole 4 is shorter than the length in the long side direction of the cross-sectional shape.

The blast hole 2 having the elongated hole shape as described above is
For example, as shown in FIG. 8, a plurality of rods 20 each having a bit 21 attached to the tip thereof are arranged side by side with the bids 21 having a larger diameter than the rods 20 alternately displaced in the front-rear direction. When viewed from the front, a punching tool is used in which the bits 21, 21 of adjacent rods 20 overlap each other at their facing parts, and each rod 20 of this punching tool is rotated and smashed while striking 1 Can be obtained by drilling to the desired depth. It is desirable that the long side dimension of the blast hole 2 is twice or more the short side dimension.

In order to excavate the cross-sectional shape of the planned tunnel by loading explosives into each of the blast holes 2 thus drilled to explode, first, the excavation surface of the planned tunnel is provided along the outer peripheral edge. As shown in FIGS. 2 and 3, an elongated explosive 5 is oriented in the longitudinal direction of the blast holes 2 in the blast hole 2 in the blast hole 2 in the blast hole row A. In this state, the blast hole 2 is loaded to a deep portion, and the blast hole 2 is filled with a filler 6 such as sand, and then the lead wire 8 led out of the hole is energized to explode the explosive 5.

This blasting force acts intensively toward the long side of the blasting hole 2 having a laterally elongated hole shape having a short distance to the explosive, that is, in the direction of the short side, and the blasting force is between the opposing long sides. The cracks 7 are separated from each other on both sides of the short side in the major axis extension direction of the blast hole 2 and reach the holes 4, and the gas generated during the blast is discharged to the outside through the holes 4. At the same time, all the blast holes 2, 2 are continuous by the cracks 7 through the holes 4, and a gap is formed along the outer peripheral edge of the excavation surface of the planned tunnel, which is not continuous with the rock mass outside.

Next, the blast holes 2a, 2a provided on both sides of the bore hole 3 are charged with the explosive 5 and the filler 6 in the same manner as above, and then blasted to generate cracks communicating with the upper and lower ends of the bore hole 3, and the blast holes The rock part surrounded by 2a and the borehole 3 is excavated and removed. After that, the blast holes 2 of the third blast hole array C and the second blast hole array B are successively blasted to excavate and remove the rock mass surrounded by the blast holes 2 and the cracks by using the space already removed. However, the tunnel of a certain length is excavated. In addition, the above-mentioned blasting was performed by blast hole rows A, 2a
You may carry out in order of C and B with a short time difference. Alternatively, the blast hole rows 2a, C, B, and A may be performed in this order. In this case,
The distance between the blast hole row A and the blast hole row B is preferably longer than the distance between the blast holes 2 and the holes 4.

FIG. 4 shows an embodiment of the invention described in claim 2, wherein the cross-sectional shape is such that the ends in the major axis direction are opposed to each other at regular intervals along the outer peripheral edge of the excavated surface of the planned tunnel. By forming the blast holes 2 of the first blast hole row
Form A1. In this case, the first blast holes are not formed between the adjacent blast holes 2 and 2 of the first blast hole array A1, and the first blast holes are provided at a portion spaced inward from the first blast hole array A1. The holes 4a having substantially the same cross-sectional shape as the blast holes 2 are provided so as to be arranged on the long side in the cross-sectional shape of the blast holes 2 of the row A1, thereby forming an arch-shaped hole row D. In this case, the distance between the adjacent blast holes 2 of the first blast hole row A1 and the blast hole 2
The distance between the holes 4a and the holes 4a in the hole row D juxtaposed in the blast holes 2 is formed to be shorter than the length of the blast holes 2 in the long side direction in the cross-sectional shape.

Further, a second blast hole row B1 is bored inside the hole row D at a constant interval from the hole row D and is surrounded by the second blast hole row B1. A borehole 3 having a vertically elongated cross section is bored in the central portion of the crushing portion to a depth substantially equal to that of the blast hole 2 in the tunnel length direction, and between the borehole 3 and the second blast hole row B1 Blast holes 2b, 2b are bored on both sides of the borehole 3 having a distance substantially equal to the distance b.

In order to excavate in a sectional shape of a planned tunnel by loading explosives into each of the blast holes 2 thus drilled and exploding, the inside of each blast hole 2 of the first blast hole row A1 is to be excavated. As shown in FIGS. 5 to 7, when the explosive 5a which is long in the longitudinal direction of the cross section of the blast hole 2 is loaded and the blast hole 2 is filled with the filler 6 and then blasted, the blasting force is increased by the cross sectional length of the blast hole 2. It concentrates on both ends in the side direction and surely causes cracks 7a from both ends toward the opposing ends of the adjacent blast hole 2 and hole 4a which are weak bodies. Therefore, the space between the blasting holes 2, 2 and the both ends of the blasting hole 2 and the both ends of the air hole 4a are continuous by the crack 7a, and the crushed material portion surrounded by the crack 7a is excavated and removed.

Next, the blast holes 2 on both sides of the borehole 3
When explosives are loaded into b and 2b and filled with filling material 6 and then blown up, cracks due to this explosion occur from both ends of the long side of the blast holes 2b and 2b toward both ends of the long side of the bore hole 3 2b and the borehole 3 are continuous due to the crack. The rock portion surrounded by the crack, the blast hole 2b and the bore hole 3 is excavated and removed.

Further, when each of the blast holes 2 of the second blast hole row B1 is blown up, a crack is generated between the opposite ends of the adjacent blast holes 2 in the same manner as described above, and the second blast hole row B1 is blasted by the blast hole 2 If the crushed objects 1 on both sides are excavated and removed through the cracks, the crushed object 1 portion of the planned tunnel will be entirely excavated.

In each of the above-mentioned blasting methods, the blasting hole 2 is filled with a filling material 6 such as sand so that the blasting force is efficiently transmitted to the hole wall. 11
As shown in FIG. 3, if the bag body 9 having flexibility that expands when the liquid 10 is injected is used, the explosive 5 can be loaded efficiently. That is, the explosive 5 is inserted into the closed front end portion of the bag body 9 and fixed, and then the bag body 9 is inserted into the blast hole 2, and then the bag body 9 is filled with the liquid 10 to fill it. The bag body 9 is inflated to be brought into close contact with the hole wall of the blast hole 2 and then blown up. As a means for fixing the explosive 5 in the bag body 9, a hook-shaped explosive locking tool is provided on the inner surface of the tip of the bag body 9, or a velvet type fastener that engages with the explosive 5 is attached. Alternatively, a string-like material for connecting gunpowder may be attached.

As shown in FIG. 12, the bag 9 has a cylindrical shape having a length equal to that of the blast hole 2 and having a major axis and a minor axis dimension slightly larger than the sectional shape of the blast hole 2. The formed one is used, and the tip side thereof is sealed, while the charging port 9b that can be sealed by a fastener or other appropriate means is provided in the center of the rear end wall 9a, and liquid is injected in a proper place. A liquid injection port 9c connectable to the hose 11 is provided. further,
At least one (two in the figure) rigid rod-shaped core material 12 is fixed to the peripheral wall of the bag body 9 in an embedded state in which the exposed surface is flush with the outer peripheral surface of the bag body 9. There is.
The bag body 9 is formed of a synthetic resin sheet material or a water impermeable sheet material in which a waterproofing agent is applied to a cloth.
When a high temperature furnace wall such as a blast furnace is broken, it is formed of fire resistant heat resistant fibers such as ceramic cloth.

When the bag 9 is not in use, it can be contracted in the width direction and the thickness direction by using the core material 12 as a holding portion as shown in FIG. Then, the explosive 5 is loaded into the blast hole 2 and inserted into the blast hole 2. At this time, the bag body 9 can be smoothly inserted into the blast hole 2 by the rigid rod-shaped core material 12, and the bag body 9 is contracted even if the blast hole 2 is slightly bent or the hole wall is uneven. The insertion work can be done easily.

After the bag 9 is inserted into the blast hole 2 in this way, the charge port 9b is sealed, and then, as shown in FIGS. 9 and 10, a liquid injection hose 11 for water or the like is added to the liquid injection port 9c. Connect and bag 9
When the liquid 10 is injected into the inside, the bag 9 expands due to the injection pressure, and the outer peripheral surface is brought into close contact with the hole wall of the blast hole 2 entirely. When this state is reached, the valve 13 of the injection hose 11 is closed and the bag body 9 is kept in close contact with the hole wall of the blast hole 2, and thereafter, the explosive 5 is blasted to cause the blasting as described above.
The blast hole 2 having a long hole-shaped cross section is inserted from both ends of the blast hole 2 on the short side.
A crack is generated in the direction of extension of the major axis.

FIG. 14 shows a modified example of the bag body 9. In this bag body 9, one rigid rod-shaped core material 12 is attached to one side portion of the bag body 9 over the entire length. A pipe 14 which also serves as a core is inserted into the other side portion so as to correspond to the liquid injection port 9c, and the end of the pipe 14 is opened in a state of being close to the inner bottom surface of the bag body 9 and the base end thereof is a bag. The body 9 has a structure in which it is fixed in a protruding state from the rear end wall portion 9a. The bag body 9 having such a structure is suitable when the blast hole 2 is provided in an upwardly inclined state.

That is, after the explosive 5 is loaded and fixed in the inner bottom portion (inside the tip portion) of the bag body 9, the bag body 9 is inserted into the blast hole 2 in an upwardly inclined state, and then the injection port 9c is inserted. When the liquid 10 is injected from the connected hose 11, the liquid 10 gradually becomes the bag 9
Air that fills the front end side while raising the liquid level from the rear end wall 9a side and is filled in the front end of the bag body 9 and reduces the blasting efficiency can be discharged to the outside through the pipe 14. . When the blast hole 2 is formed horizontally, the pipe 14 is used for liquid injection and the liquid injection port 9c is used.
Can be used as a drainage port.

FIG. 15 shows another modified example of the bag body 9. The bag 9 has a drain port 9d having a diameter smaller than the injection port 9c provided on the rear end wall 9a of the bag body 9 at the front end thereof. A pipe 15 serving as a core material is provided in the bag body 9 in correspondence with the liquid injection port 9c while being bored in the wall surface, and the opening portions at the tip and the base end thereof are formed from the front and rear wall surfaces of the bag body 9, respectively. It is made to project to the outside. The other structure is similar to that of the above-mentioned embodiment.

With this construction, as shown in FIG. 11, after the explosive 5a is loaded in the deep position of the blast hole 2 in a horizontal state and the bag body 9 is inserted into the blast hole 2 after that, When the liquid 10 is injected through the hose from the liquid port 9c,
The bag body 9 is expanded by the liquid 10 injected into the bag body 9 so that the outer peripheral surface of the bag body 9 is brought into close contact with the hole wall, and a part of the liquid 10 is discharged from the small-diameter drain port 9d into the deep part of the blast hole 2. The excess liquid is discharged to the outside through the pipe 15 which also serves as the core material while filling the part. By detonating the explosive 5a in this state, cracks are generated in the direction of extension of the blast hole 2 from both ends on the short side of the blast hole 2 having an elongated hole shape in the same manner as described above.

[0027]

As described above, according to the blasting method of the present invention, blast holes having a cross-section elongated hole shape are formed at predetermined intervals at the crushed material such as rock mass, and end portions on the long side of adjacent blast holes are formed. After piercing to the desired depth in a state of facing each other and forming a hole between the adjacent blast holes, a long and narrow explosive is loaded in the central portion in the width direction of the blast hole, and the blast hole is placed in the blast hole. Since it is characterized by exploding after filling with a filling material, a blast hole with an oval cross section can be easily drilled compared to the conventional drilling operation of forming a notch in a blast hole with a circular cross section. Not only that, but by exploding the explosive charged in the blast hole, the blasting force is concentrated on the blast hole having an oval cross section and the crack is surely generated in the major axis direction of the blast hole. It can be done.

Further, the blast holes are formed at regular intervals with their long-diameter side ends facing each other, and vacant holes are bored to a desired depth in the intermediate portion between adjacent blast holes. Therefore, when a blast hole is blown up, a crack is generated from the long side end of the blast hole toward the vacancy hole, and the blast hole can be made to continue through the vacancy hole through the crack. Can be set in advance to the maximum distance that can be connected by cracks, and in combination with the decrease in the number of blast holes, the amount of explosive used, etc. can be minimized, which is economical and It enables efficient blasting.

According to the invention described in claim 2,
A blast hole having a cross-sectional elongated hole shape is formed at a predetermined interval in a crushed object such as bedrock, and holes are provided in the vicinity of the blast hole so as to be arranged on the long side of the blast hole. A long explosive is loaded into the bottom of the blast hole in the direction of the long side of the blast hole, and the blast hole is filled with a filling material before blasting. Since the explosive that is long in the direction is loaded, the explosive force of the explosive concentrates at the end of the blast hole in the direction of the long side of the cross section, and from that end to the adjacent blast hole and hole that are weak parts, surely. Can crack. Therefore, between the blasting holes and between both ends of the blasting hole and between both ends of the hole are continuous by a crack, and the crushed object portion surrounded by this crack can be efficiently excavated and removed, and the blasting hole is the same as above. It is possible to reduce the number of holes to be drilled and the amount of explosive used, and it is possible to perform accurate excavation along the outer peripheral edge of the planned excavation surface.

[Brief description of drawings]

FIG. 1 is a simplified front view when the method of the present invention is used for tunnel excavation,

FIG. 2 is a simplified vertical sectional front view showing a state in which explosives are loaded in the blast holes on both sides of the hole,

FIG. 3 is a simplified cross-sectional plan view thereof,

FIG. 4 is a simplified front view for explaining another blasting method of the present invention,

FIG. 5 is an enlarged vertical sectional front view of a part thereof,

FIG. 6 is a transverse plan view thereof,

FIG. 7 is a vertical sectional side view thereof,

FIG. 8 is a simplified plan view of a blast hole excavator having an oval cross section;

FIG. 9 is a simplified front view of a state in which a bag body filled with explosives is inserted into the blast hole,

FIG. 10 is a simplified vertical sectional side view thereof,

FIG. 11 is a simplified vertical sectional side view of the modification.

FIG. 12 is a simplified perspective view of a bag body,

FIG. 13 is a simplified perspective view of the bag body in a contracted state,

FIG. 14 is a partially cutaway simplified perspective view showing another structure of the bag body,

FIG. 15 is a partially cutaway simplified perspective view showing still another structure of the bag body.

[Explanation of symbols]

 1 crushed object 2 blast hole 3 borehole 4, 4a hole 5, 5a explosive 7, 7a crack

Claims (2)

[Claims] 1. Blasting holes each having a cross-section elongated hole shape are drilled to a desired depth at a predetermined depth in a crushed object such as bedrock at predetermined intervals and with the long side ends of the blasting holes facing each other. The rock mass is characterized by forming holes between the blast holes, loading a long and narrow explosive in the widthwise central portion of the blast holes, filling the blast holes with a filling, and then blasting. Bombing method such as. 2. A crushing object such as rock mass is provided with blast holes each having a cross-section elongated hole shape at predetermined intervals, and the holes are arranged in the vicinity of the blast holes by arranging them on the long side of the blast holes. A method for blasting rock mass, characterized in that a blasting hole is provided, a long explosive is loaded into the bottom of the blasting hole in the direction of the long side of the cross section of the blasting hole, and the blasting hole is filled with a filling material before blasting.