JPH06174400A - Bench blasting method - Google Patents

Abstract

PURPOSE:To make an impact pressure and a gas pressure act uniformly and strongly in a blast hole by filling up gel water in a gap of a charged explosive from a blast hole wall and in the whole of the blast hole. CONSTITUTION:An explosive container 1 is lowered a little into a blast hole 8 by using a cord 4, sand 9 in a proper quantity is thrown in from an opening 5 and an explosive material 10 is charged thereon. Next, a waterproof cap 6 is put in the opening 5 and closed hermetically and the container is sunk deep to the lower part of a blast hole 8 by using the cord 4. Thereafter an explosive container 11 is suspended a little in the blast hole 8 by a cord 12, the explosive material 10 is charged, the waterproof cap 6 is set and the container is lowered so that it be brought into contact with the explosive container 1 sunk previously in the blast hole 8. Then, water 18 and gel powder 14 of which the main constituent is water-absorbing polymer are thrown into the blast hole 8 so that gel water 15 be produced in the blast hole 8, and the outer peripheries of the explosive containers 1 and 11 and the whole of the inside of the blast hole 8 are filled up wit the gel water 15. Then, the explosive containers 1 and 11 are exploded.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an explosive blasting method of an explosive construction method using explosive destructive power in civil engineering and construction.

[0002]

2. Description of the Related Art Conventional explosive blasting methods include a method in which a bulk ANFO explosive is allowed to flow naturally into a bench / drilling hole to uniformly or disperse the charge, and tamping is performed with sand, etc. A method is known in which it is dropped inside and sealed by sand tamping or the like.

[0003]

In the conventional blasting method,
In the case of water holes or when there is water in the holes (blast holes), low-cost bulk ANFO and non-waterproof cartridge explosives could not be used. Also, in the former blasting method of the related art, due to the nature of the drilling machine, the diameter becomes the same from the upper layer to the lower portion of the bench according to the bit diameter, and if the bulk ANFO explosive is used for dense packing, it will be uniformly packed, It was difficult to optimize the explosive layer in the middle and upper layers, and it was impossible to adjust the diameter of the lower and upper layers of the bench, and as a result, there was a problem that the upper portion of the bench was overcharged. Generally, a large explosive destructive force is required because the bedrock load increases according to the lower part of the bench.

In the latter blasting method of the related art, a gap is created between the cartridge explosive and the hole wall of the drilling hole (blasting hole), and this serves as an air cushion at the time of blasting to increase the loss of blasting energy. All of the conventional blasting methods have a problem that a large lump remains on the upper part of the bench, secondary crushing thereof occurs, and a large amount of blasting vibration and blasting noise are generated.

The problem to be solved by the present invention is to solve these conventional problems, to effectively and uniformly exert a crushing force, and to suppress blasting dust, blasting vibration and blasting noise to a low level, and further An object of the present invention is to provide a bench blasting method capable of safely and easily using costly explosives.

[0006]

Means for Solving the Problems The gist of the present invention, which has solved the above problems, is as follows: 1) Blasting in a state in which gel water is filled in the gap between the wall of the blast hole and the explosive loaded and the entire blast hole. Bench blasting method 2) Put a waterproof explosive container whose surface is covered with an antistatic film into the blasting hole, charge explosives from the opening of the explosive container, and seal the opening with a waterproof cap,
Next, the explosive container is submerged at a predetermined position in the blasting hole, gel water is filled into the blasting hole, and then the blasting is performed. 3) Bench blasting method 3) Non-electrostatic explosive container made of waterproof material Into the blast hole, charge the explosive from the opening of the explosive container, seal the opening with a waterproof cap, then submerge the explosive container in place in the blast hole, and put gel water into the entire blast hole. Bench blasting method characterized by filling and then blasting 4) The bench blasting method according to any one of 1 to 3, wherein the gel water has a water-absorbing polymer as a main component.

[0007]

In the present invention, gel water is filled between the charged explosive and the wall of the blast hole, so that the shock wave at the time of blast propagates the gel water with little energy loss and spreads around the hole wall and all the inner surfaces above and below. Strong and uniform impact pressure and gas pressure act. Therefore, no uncrushed large lumps are generated in the upper part.

Since it is gel water, it does not flow out from the holes having small cracks on the wall of the holes, and the blast holes can be reliably filled. Further, since the gel water is present on the outer periphery of the explosive, the blast dust is trapped in the gel water and quickly settles to greatly reduce the scattering of the blast dust. In addition, blasting vibration and blasting noise can be suppressed to a low level by the uniform pressure.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. Example (see FIGS. 1 and 2) FIG. 1 is a partially cutaway front view showing an explosive container of the present example,
FIG. 2 is an explanatory view showing the explosive / filling step of the embodiment.

Explosive container 1 for filling explosive of the present embodiment
Is a high-pressure molded paper tube 2 having a bottom, and a string 4 having a tensile strength of 60 kg having a width of 0.7 mm and a width of 12 mm is hung from the top to the bottom, and they are wrapped in an antistatic reinforced polytube 3. The cylindrical structure has a polyethylene film that is heated and shrunk so that the polyethylene film is brought into close contact with the surface of the high-pressure molded paper tube 2 to be waterproof. The string 4 is pressed against the surface of the high-pressure molded paper tube 2 by the contraction of the reinforced poly tube 3 so as not to move, and the explosive container 1 can be suspended. A waterproof cap 6 for sealing the opening 5 at the upper part of the explosive container 1 is a lid body integrally formed with a plastic and fitted to the opening 5, and also has a blasting lead wire 7 in the center.
Has penetrated.

In this embodiment, the explosive container 1 is slightly lowered and lowered in the blast hole 8 by using the string 4, and an appropriate amount of sand (grinding powder) 9 is introduced through the opening 5 and the explosive material 10 is placed thereon. Charge (see FIG. 2 (a)). Next, the waterproof cap 6 is fitted into the opening portion 5 to be hermetically sealed, and the string 4 is used to deeply sink into the lower portion of the blast hole 5 (see FIGS. 2B and 2C). After that, the explosive container 11 having the same structure as that described above is slightly suspended in the blast hole 8 with the string 12 and filled with the explosive material 10 (see FIG. 2 (d)). Lower it so that it contacts the explosive container 1 that was previously sunk, then water 18
And gel powder 14 containing a water-absorbing polymer as a main component are charged into the blast hole 8 to generate gel water 15 in the blast hole 8, and the outer periphery of the explosive containers 1 and 11 and the entire blast hole 8 are filled with the gel water 15. (See FIG. 2E). Then, the explosive containers 1 and 11 are detonated by the lead wire. Since the two explosive containers 1 and 11 are in contact with each other, they explode and simultaneously explode. Here, in addition to the detonation shown in FIG. 2 (e), sand is put in the lower part of the second explosive container 11, the explosive material 10 is charged on the sand, and the waterproof cap 13 is applied, and then the explosive material is sunk first. It is also possible to suspend the first explosive container 1 at a position slightly above the first explosive container 1 and fill the blast hole with the gel water 15 in this state (see FIG. 2 (f)). In this case, the explosive material can be dispersed and charged.

In the state shown in FIGS. 2 (e) and 2 (f), a lead wire ignites and blasts. The explosive force intervenes the gel water, and the inner wall surface of the entire blast hole 8 is uniformly and strongly subjected to a strong impact pressure and gas pressure, and is crushed uniformly without leaving a large lump, and further, the gel water scatters dust. Dampen vibration.

In the present invention, it is easy to charge the explosive material unevenly in the vertical direction, and the outer periphery of the explosive container is filled with gel water even if the outer diameter of the explosive container changes. Can be maintained.

The explosive container 16 shown in FIG. 3 is an example in which the high-pressure molded paper tube 2 is impregnated with a waterproof liquid to be in a waterproof state.
The string 4 is fixed to the surface of the high-pressure molded paper tube 2 with an adhesive tape 17. This can also be similar to the explosive containers 1 and 11 of the above embodiment.

[0015]

As described above, according to the present invention, due to the presence of gel water, the explosive is closely packed, and the impact pressure and gas pressure act uniformly and strongly in the blast hole. It has a high crushing power and can be crushed uniformly without leaving uncrushed large lumps. You can reduce the energy loss of explosives,
The amount of explosives can be reduced. Moreover, the amount of dust scattered was reduced by 60 to 80%, and the blasting vibration and blasting noise were also reduced. Moreover, there is an advantage that low-cost explosives can be used safely and easily.

[Brief description of drawings]

FIG. 1 is a partially cutaway front view showing an explosive container according to an embodiment of the present invention.

FIG. 2 is an explanatory view showing an explosive filling step of the example.

FIG. 3 is a partially cutaway front view showing another example of the explosive container.

[Explanation of symbols]

 1 Explosive Container 2 High-Pressure Paper Tube 3 Polytube 4 String 5 Opening 6 Waterproof Cap 7 Lead Wire 8 Blast Hole 9 Sand 10 Explosive Material 11 Explosive Container 12 String 13 Waterproof Cap 14 Gel Powder 15 Gel Water 16 Explosive Container 17 Adhesive Tape 18 water

Claims (4)

[Claims] 1. A bench blasting method comprising blasting in a state in which gel water is filled in the void between the blasting hole wall and the loaded explosive and the entire blasting hole. 2. An explosive container whose surface is covered with an antistatic film and is waterproof is placed in a blast hole, explosive is charged through the opening of the explosive container, and the opening is sealed with a waterproof cap, and then A bench blasting method characterized in that an explosive container is submerged at a predetermined position in the blasting hole, gel water is filled in the blasting hole, and then the blasting is performed. 3. A non-electrostatic explosive container made of waterproof material is placed in the blast hole, explosive is charged through the opening of the explosive container, the opening is sealed with a waterproof cap, and then the explosive container is closed. A bench blasting method, characterized in that the blasting hole is submerged at a predetermined position, gel water is filled in the entire blasting hole, and then blasting is performed. 4. The bench blasting method according to claim 1, wherein the gel water contains a water-absorbing polymer as a main component.