JPS63150600A - Method of blast construction - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a blasting method, and particularly to a blasting method that makes it possible to effectively utilize the explosion energy of explosives.

(Prior Art) For rock crushing work, etc., a blasting method using an explosive called dynamite is generally used.

The other side of this method, the ABS (Aqua Blasting System) method, uses a PVC pipe filled with water and loaded with explosives, which is inserted into the blast hole.
This is a construction method that causes it to explode.

This construction method uses the blasting effect of the incompressible water that fills the pipe to apply the impact force of the explosive at right angles to the pipe wall, effectively creating a wide cylindrical wave, which prevents loss of fracturing energy and reduces it. The amount of explosives produced an efficient crushing effect, and it attracted attention as a construction method with low noise, low vibration, and fewer flying stones.

(Problem to be solved by the invention) However, even with this construction method, the hole diameter of the explosion hole is larger than that of PVC pipe, taking into consideration the unevenness during drilling and ease of insertion.
Since there is a gap between the explosion hole and the PVC pipe, energy loss caused by this space has become a problem.

In other words, if there is a gap between the blast hole and the pipe, some of the blast pressure energy during the explosion will compress that space. In other words, part of the explosion energy is absorbed by the space, thereby significantly reducing the crushing energy.

In addition, other disadvantages of this method include the troublesome work of loading explosives and water into the PVC vibrator, the complicated blasting preparation work, the unpleasant odor caused by the combustion of the PVC vibrator during the explosion, and the chlorine There is a problem with the generation of toxic gases such as

The present invention solves the above-mentioned problems, and while enjoying the advantages of conventional ABS construction methods, it is possible to convert explosion energy into crushing energy more efficiently than before, and to perform blast preparation work efficiently. The purpose is to prevent the generation of strange odors and toxic gases during explosions.

(Means for Solving the Problems) In order to achieve the above object, the present invention involves inserting a flexible and watertight bag containing an explosive into a pre-drilled explosion hole, and The bag is inflated in the blast hole by injecting water or a muddy water mixture of water and earth and sand through the opening, and is brought into close contact with the hole wall.The opening of the blast hole is then closed, and then the bag is expanded. It is characterized in that the explosive is ignited via a fuse led out from the fuse.

(Function) The bag expands by supplying water or a muddy mixture of water and earth, thereby completely expelling the air in the blast hole.

(Example) Hereinafter, an example of the present invention will be described in detail using the drawings.

1 to 4 are explanatory sectional views showing blasting preparation work according to the present invention.

In each figure, 1 is an explosion hole drilled in the tunnel bedrock E, and 2 is a cylindrical flexible bag for storing dynamite (explosives) 3, such as a highly watertight plastic bag made of polyethylene.

The plastic bag 2 is slightly thicker than the diameter of the blast hole 1, about 4/3 of the length of the hole, and protrudes beyond the hole opening when inserted.

The dynamite 3 is made up of a parent dynamite 3a with a detonator embedded therein and an incremental material 3b wrapped together in a cylindrical portion, and a fuse 1*3c is connected to the end of the dynamite 3.

In FIG. 1, after the blast hole 1 is bored, the plastic bag 2 is inserted into the innermost part of the blast hole 1 using the insertion rod 5. At this time, the fuse 3C of the dynamite 3 is led out from the opening of the plastic bag 2.

Next, as shown in FIG. 2, the discharge vibrator 7 of the injection pump 6 installed in the mine near the explosion hole 1 is connected to the opening of the plastic bag 2, and water or sediment is poured into the water. The mixed muddy water 4 is poured into the bag 2.

By injecting water or muddy water 4, the bag 2 expands into a substantially cylindrical shape and comes into contact with the hole wall surface of the explosion hole 1. By further pressurizing water or muddy water 4 from this state,
The plastic bag 2 is flexibly deformed in contact with the wall surface of the explosion hole 1, and closely adheres along the unevenness of the wall surface.

Next, as shown in FIG. 3, lift the protruding part 2a from the hole of the plastic bag 2 upwards, maintain the inflated state of the plastic bag 2 and keep the water or muddy water 4 from spilling, and hold it in that position. Fill the hole with filler 8 such as sand or clay as shown in Figure 4, and close the hole. Finish the blasting preparation work with the ejected.

When the dynamite 3 is ignited through the fuse 3C after the preparation work is completed, the rock E is crushed by the blasting energy of the dynamite 3 in a specific area characterized by the explosion hole 1.

At this time, in the conventional HEBS construction method, a gap is created between the vibrator and the explosion hole 1, and the air layer existing in this gap absorbs a part of the explosion energy and reduces the energy. Since the bag 2 is in complete contact with the hole wall, there is no air layer at all.

Therefore, the explosion energy acts at right angles to the hole wall of the explosion hole 1 only through the incompressible water or muddy water 4, so the explosion energy propagates efficiently as a cylindrical wave.
This prevents loss of crushing energy and provides efficient crushing action with less explosive charge.

Furthermore, in the event of an explosion, the plastic bag 2 will burn, but it is made of polyethylene or the like, and since it only needs to have the strength to withstand the pressure of injected water or muddy water, it can be made of a thin material. There is no strange odor or toxic gas generation.

In the example, a plastic bag made of polyethylene or the like was used as a flexible and watertight bag, but any bag made of a material that is thin and can sufficiently withstand water pressure can be used. Of course.

(Effects) According to the blasting method of the present invention, as explained in detail in the embodiments above, the flexible bag expands by supplying water or muddy water and comes into close contact with the hole wall, so that the air inside the blast hole is It is completely expelled and energy loss factors can be completely removed. Moreover, since the preparation work for blasting can be carried out according to the above-mentioned procedure, the assembly and preparation work are also simple and highly efficient. Furthermore, there is no risk of odor or toxic gas being generated due to combustion during an explosion.

Therefore, the blasting method of the present invention can be used as a construction method with lower noise, lower vibration, and fewer flying stones than conventional methods, and is useful for demolishing concrete buildings and crushing rock.

[Brief explanation of the drawing]

1 to 4 are explanatory sectional views showing blasting preparation work according to the present invention. E...Bedrock 1...Explosion hole 2...Plastic bag (flexible water-tight bag) 3...Dynamite (explosive) 3C...Fuse 4...Water or muddy water 8・・・
・Filling

Claims (1)

[Claims] (1) A flexible, watertight bag containing explosives is inserted into a pre-drilled explosion hole, and water or muddy water mixed with water and sand is injected through the opening of the bag. Therefore, the bag is inflated within the explosion hole and brought into close contact with the hole wall, after which the opening of the explosion hole is closed, and then the explosive is ignited via a fuse led out from the bag. A blasting method characterized by