WO2015026155A1

WO2015026155A1 - Structure for underwater blasting and underwater blasting method using same

Info

Publication number: WO2015026155A1
Application number: PCT/KR2014/007728
Authority: WO
Inventors: 우주식; 김영근
Original assignee: Woo Jusik; Kim Younggeun
Priority date: 2013-08-20
Filing date: 2014-08-20
Publication date: 2015-02-26
Also published as: KR101319736B1

Abstract

The present invention relates to a structure for underwater blasting and an underwater blasting method using the same. The structure for blasting comprises: a pipe-shaped pipe body (10) having the top and bottom thereof open; top and bottom caps (20A and 20B) installed on the open top and bottom, respectively, of the pipe body (10) and sealing the pipe body (10); a charged portion (30) inserted in the inner bottom portion of the pipe body (10) and holding explosives; and a tamping portion (40) filled in the inner top portion of the pipe body (10) and covering the charged portion (30). A plurality of plate springs (S) is installed on the outer circumference of the bottom cap (20B), and a sleeve (12) is installed at the outside of the plate springs (S) to enclose the plate springs (S) and can be removed from the plate springs (S) by means of a wire (13). The present invention according to the configuration as described above uses a structure for blasting and enables explosives to be installed and fixed in bedrock underwater, so that the occurrence of dead pressure is prevented, and underwater blasting work can be reliably and efficiently performed even when typical explosives are used.

Description

Underwater Blasting Structure and Underwater Blasting Method

The present invention relates to an underwater blasting structure and an underwater blasting method using the same, and more particularly, by blasting a protruding rock in the water in order to construct a waterway for the construction of a marine structure or the construction of a vessel or a harbor. The present invention relates to an underwater blasting structure used for removal and an underwater blasting method using the same.

In general, when installing a structure such as a bridge or a seabed, or when constructing a waterway or a port through which a ship passes, dredging the underwater bottom is preceded. If there is a rock in the water, the work such as blasting is performed. Underwater blasting work to remove the rock in the water is generally attached to blasting by attaching explosives to the surface of rocks or structures in the underwater, underwater suspension blasting in the form of a bundle by exploding the explosives in the water, Alternatively, a perforation is made using a perforator to penetrate the inside of the to-be-damaged object such as rock, and then an explosive underwater blasting is performed by installing explosives in the perforated hole.

However, the blasting work by underwater attachment blasting is difficult and dangerous because the divers install the explosives by diving, and the blasting efficiency is low, and the blasting work by underwater suspension blasting is generated by the explosives of the water underwater. In order to deform or destroy an object by the pressure, it has a great effect on the aquatic ecosystem and the efficiency of rock removal is lower than that of underwater drilling. Therefore, the underwater drilling method is generally used to remove underwater rocks.

An underwater rock blasting apparatus and a method disclosed in Patent No. 581174 can be cited as an example of the underwater drilling blasting method. The underwater rock blasting method disclosed in this patent document first shows a barge 110 as shown in FIG. After fixing the upper part of the blasting rock, drill the rock while vertically lowering the bit in the punching machine 100, and then by loading the explosives in the perforated hole to explode the gas pressure or impact caused by the explosion of the previous blasting hole. Exothermic reactions may not be sustained due to pressure or compression of explosives in water or water hammer, so that explosives may remain, and so-called dead pressure may occur. The same high-performance explosives are used, which are safe because they explode by friction or impact even without a primer. There is a possibility of generating high.

On the other hand, general explosives, such as emulsion explosives, which are not high-performance explosives, are water-in-oil droplets, and there are bubbles inside them. When such explosives are installed in water, bubbles burst by water pressure. There is a risk of explosion, and therefore it is difficult to use general explosives for underwater blasting.

Moreover, in the case of powdered explosives (crude milk explosives), the explosive density is low, making it practically impossible to use underwater.

Therefore, it is required to develop an underwater blasting method that can accurately and effectively perform underwater blasting operations while using general explosives or powdered explosives instead of high-performance explosives.

The present invention has been made to solve the problems of the conventional underwater blasting method as described above, while it is possible to use the general explosives, and can accurately and safely load the explosives in the perforated rock hole, and at the same time the residual explosives due to the generation of dead pressure An object of the present invention is to provide a structure for underwater blasting and a method for underwater blasting using the same, which can prevent the occurrence of water.

An object of the present invention to provide an underwater blasting structure is a pipe-shaped tubular body having a top and bottom open and the top and bottom open; Upper and lower caps respectively installed at upper and lower portions of the tube body to seal the tube; An injection part inserted into an inner lower part of the tube and containing explosives; Filled in the inner upper portion of the tubular body made of a full-colored portion, the outer circumference of the lower cap is provided with a plurality of leaf springs, the outer surface of the leaf spring by wrapping a leaf spring by a wire while wrapping the leaf spring By configuring the sleeve to be removed therefrom.

Another object of the present invention to provide an underwater blasting method using an underwater blasting structure, the underwater blasting method, the preparation step of fixing a barge provided with a perforator on the sea of the work site; A seating hole forming step of forming a seating hole in which a guide casing is seated on a rock in the water by using the perforator; A guide casing installation step of seating the guide casing in the seating hole; Inserting a drilling bit into the guide casing to form an explosive charge hole for drilling explosive charge holes of a predetermined depth in the rock; After removing the perforation bit, a blasting structure is provided inside the guide casing and a leaf spring and a sleeve are provided at the bottom, and the blasting structure is seated in the explosive charge hole, and then the wire connected to the sleeve is pulled to remove the sleeve. Installing and fixing the blasting structure for fixing the blasting structure to the explosive charge hole by removing an end portion of the leaf spring by removing; It is achieved by blasting step of exploding the explosives by using the detonation wire connected to the charge portion in the state of removing the guide casing from the water.

The present invention is characterized in that a through-hole is formed in the upper cap, and through the through-hole, the initiator cable which is connected to the detonator primer inside the tubular body is drawn out to the top, and a heat shrink tube is installed on the outer circumferential surface of the initiator cable.

In another aspect, the present invention is characterized in that the sleeve is made of Teflon material or a plurality of guide protrusions are formed on the inner peripheral surface.

And the present invention is characterized in that the tube is a synthetic resin material made of PVC or PE.

In addition, the present invention is characterized in that the adhesive is applied between the upper, lower cap and the tube.

And the present invention is when the drilling depth of the explosive charge is less than a certain depth, the blasting structure is installed inside the guide casing in a state in which the tubular body, the upper, lower cap, the charging portion and the color portion is completely assembled, the explosive charge When the drilling depth of the loader is greater than or equal to a predetermined depth, the lower cap is attached to the explosive loader with the leaf spring and the sleeve attached to the lower end of the tubular body, and then the wire is pulled to the inside of the explosive loader. After the tube is fixed, the filling part is filled in the inside of the tube to be positioned at the lower side of the tube, and an chromosome is formed on the upper portion of the tube, and then the upper portion of the tube is sealed to seal the upper portion of the tube for blasting structure. It is characterized in that it is installed inside.

The present invention can be firmly installed and fixed to the explosive charges formed in the rock under water by using a blasting structure to prevent the occurrence of dead pressure phenomenon to safely and efficiently use underwater explosive work while using general explosives I can do it.

In addition, the present invention is provided with the same explosives installation environment as on land because the explosives are installed using a blasting structure on the underwater rock, and as a result, because the explosives and powder explosives can be easily used, economics and safety are improved.

And the present invention is a plurality of lower portion of the blasting structure The leaf spring is installed, and the blasting structure is fixed to the inner wall of the blasting charge hole formed in the underwater rock, so that the blasting structure does not float due to the buoyancy of seawater, and its installation position is fixed. The explosives can be positioned accurately, so that the blasting can be done accurately and safely.

In addition, a plurality of O-rings are respectively installed in upper and lower caps for sealing the blasting structure of the present invention, and a heat shrink tube is installed on the outer circumferential surface of the detonation cable to effectively prevent the inflow of seawater into the blasting structure.

Figure 1 shows an example of a conventional underwater drilling method

2 is a perspective view showing an example of the blasting structure according to the present invention;

3 is an exploded perspective view of FIG. 2;

4 is a cross-sectional view of FIG.

5 is a cross-sectional view showing an example of an upper cap according to the present invention;

6 is a flow chart showing an example of the underwater blasting method using the underwater blasting structure according to the present invention,

7 is a configuration diagram showing an example of the underwater drilling device according to the present invention,

8 is a configuration diagram showing an example of the seating hole forming step and the casing seating step according to the present invention,

Figure 9 is a block diagram showing an example of the rock-explosion charge hole forming step according to the present invention,

10 is a configuration diagram showing an example of the blasting structure installation step and the blasting structure fixing step according to the present invention.

1: barge 2: perforator

2A: Guide Casing 2B: Drill Bit

3: settler 4: explosive loader

5: blasting structure 10: tube

11: through hole 12: sleeve

12A: Guide protrusion 13: wire

20A: Upper Cap 20B: Lower Cap

21: O-ring 22: through hole

30: Charge Contract 31: Detonation Primer

32: explosive 40: color part

C: Detonation cable T: Heat shrink tube

S: leaf spring

Hereinafter, the configuration and operation of the present invention through the accompanying drawings showing a preferred embodiment in more detail.

The present invention is to provide an underwater blasting structure and a method for underwater blasting using the same, which can safely remove the rock in the water, for this purpose, the underwater blasting structure of the present invention as shown in FIG. , The upper and lower caps (20A, 20B), the charge portion 30 and the color portion 40, wherein the lower periphery of the lower cap (20B) is provided with a leaf spring (S) and the sleeve 12, A plurality of wires 13 are connected to the upper portion of the sleeve 12.

The tubular body 10 is a hollow pipe shape in which the upper and lower parts are opened and the through hole 11 is formed therein, as shown in FIGS. 2 and 3, and the explosive charge is filled in the through hole 11 inside the tubular body 10. And is inserted into the explosive charge hole 4 formed in the rock by the perforator 2 and then fixed.

At this time, the tube 10 is not only easy to handle by using a lightweight synthetic resin pipe such as PVC or PE, but also when the explosives filled in the tube 10 are exploded, the tube 10 is also easily broken, so The loss can be reduced.

In addition, the upper and

lower caps

20A and 20B are inserted into the open upper and lower portions of the hollow pipe-shaped tubular body 10, respectively, to seal the upper and lower parts of the tubular body 10, and the upper and

lower caps

20A and 20B are illustrated in FIG. 4 and 5, a plurality of O-rings 21 are installed in a portion of the solid circular rod inserted into the upper and lower portions of the tubular body 10 and in contact with the inner wall of the tubular body 10. , Just by fitting the

lower cap

20A, 20B to the upper and lower portions of the tubular body 10, the airtightness between the upper and

lower caps

20A, 20B and the tubular body 10 is maintained. In order to maintain the upper and lower caps (20A, 20B) and the tubular body (10) in contact with each other it is also preferable to apply an adhesive and then fitting.

And the upper cap (20A) is connected to the detonator primer 31 installed in the charge portion 30 inside the tubular body 10 to be described later as shown in Figure 5 for the detonation cable (C) to be drawn out to pass through The through-hole 22 is formed, wherein the heat shrinkable tube (T) is installed on the outer circumferential surface of the detonation cable (C) so that seawater does not flow through the through-hole (22), whereby the airtightness of the through-hole (22) Stays solid.

When the upper and lower caps (20A, 20B) is installed in the upper and lower portions of the tubular body 10 as described above, the tubular body 10 is in a sealed form. Thus, the tubular body 10 in the sealed form is placed on a rock in the water. When inserted into the perforated explosive loader 4, the tubular body 10 does not stay inside the explosive loader 4 but is raised by the buoyancy of the seawater filled in the explosive loader 4 so that the tubular body 10 ) Needs to be firmly fixed to the inside of the explosive charge holder 4.

Accordingly, in the present invention, a plurality of leaf springs (S) are installed along the circumference of the lower cap 20B installed in the lower portion of the tube body 10, and the tube body 10 is inserted into the explosive charge holder 4 and then the plate spring. The end of the (S) is released so that the end of the leaf spring (S) can be fixed to the side of the explosive charge hole (4), for this purpose a plurality of leaf springs (S) each have a beveled shape by When installed in the cap 20B, the outer surface of the tubular body 10 is protruded. At this time, the leaf spring S is fixed to the side surface of the lower cap 20B by screws or the like.

On the other hand, after the explosive loader 4 is formed on the rock by a perforator, it is necessary to check whether the explosive loader 4 is correctly drilled or whether the tubular body 10 is correctly inserted into the explosive loader 4. If the explosive charge (4) is not properly punctured or the tube 10 is not inserted correctly in the explosive charge (4), the tube 10 should be able to be removed from the explosive charge (4), As described above, when the leaf spring S protrudes out of the tube 10, it is not easy to take the tube 10 from the explosive charge hole 4.

Accordingly, in the present invention, by installing the cylindrical sleeve 12 of the upper and lower portions to the outside of the leaf spring (S) fixed to the side of the lower cap (20B) to wrap around the end of the leaf spring (S) The expansion is prevented so as not to be caught by the side wall of the explosive charge hole (4).

At this time, the upper and lower heights of the sleeve 12 cover the height of the leaf spring (S) sufficiently while overhanging the outer circumferential surface of the tubular body 10 when the sleeve 13 is pulled upward by the wire 13 to be described later. It is desirable to have a height that can be raised.

And when the pipe body 10 is correctly seated in the explosive charge hole 4, the leaf spring (S) is operated to insert the pipe body 10 inserted into the explosive charge hole (4) into the explosive charge hole (4) To this end, the sleeve 12 has a plurality of sleeves 12 so as to easily remove the sleeve 12 installed to surround the outside of the leaf spring (S) so that the end of the leaf spring (S) can be expanded to the outside of the tube (10). Two wires 13 are connected and installed, and the other end of the wires 13 extends to the barge 1 above the sea level and is connected to an outer sleeve of the leaf spring 4 by the operator pulling the wires 13. (12) is removed so that the end of the leaf spring (S) is expanded to the outside of the tubular body 10 to be fixed to the inside of the explosive charge hole (4).

In this case, the sleeve 12 is made of metal, or preferably made of Teflon material having a low frictional force so that it can be easily removed from the leaf spring S by pulling the wire 13.

On the other hand, when the upper and lower heights of the sleeve 12 is pulled upward by the wire 13 as described above, even if caught on the outer peripheral surface of the tubular body 10 has a height that can be easily raised or low friction force Teflon Even though the inner surface of the sleeve 12 is caught on the outer circumferential surface of the tubular body 10 during the ascending process of the sleeve 12, it may not be raised any more. To prevent this, a plurality of hemispherical guides are provided on the inner circumferential surface of the sleeve 12. It is desirable to form the projection 12A so that the sleeve 12 can be easily raised.

The charge portion 30 inserted into the inner lower portion of the tubular body 10 is composed of a detonation primer 31 and the explosive charge 32, as shown in Figure 4, the structure of the charge portion 30 is generally widely used Since the same explosive structure is present, a detailed description thereof will be omitted.

The inside of the tubular body 10 is composed of a charge portion 30 is filled with explosives, and a full-color portion 40 located in the upper portion of the charge portion 30, wherein the color portion 40 is filled with sand and so on As a result, when the explosives of the charge portion 30 filled in the lower part explode, the explosive force is suppressed from acting upward, and instead, the explosive force is induced in the horizontal direction, thereby improving the explosion efficiency.

The present invention is to perform underwater blasting using a blasting structure consisting of the above structure, wherein the underwater blasting method according to the present invention is a preparation step (S100), seating hole forming step (S200) as shown in FIG. , Guide casing installation step (S300), explosive charge hole forming step (S400), blasting structure installation and fixing step (S500) and blasting step (S600).

(1) Preparation step (S100)

In this step, the barge 1 is placed on top of the rock that needs underwater blasting to prepare the driller 2 to drill the required number of explosive loaders 4 for the underwater rock.

The barge 1 according to the present invention forms a barge 1 by arranging a pair of small barges as shown in FIG. 7 and then using a connecting member such as an H beam to form a barge (1). It is implemented by boarding and fixing the punching machine 2 generally used on the upper part of 1).

After the barge 1 is positioned in the proper position by the above process, it is necessary to fix the barge 1 so that it does not move or flow up and down during the drilling operation. The barge 1 is fixed at an appropriate height on the sea surface by installing fixed beams (not shown) and lowering them so that the bottom of the fixed beams reaches the bottom of the water.

(2) seating hole forming step (S200)

This step is to form a seating hole (3) in the rock so that the guide casing (2A) can be seated on the rock in the water by using a perforator (2) located on the barge (1), such a guide casing ( 2A) then serves to guide the path through which the drilling bit 2B or tube 10 is inserted.

When forming the seating hole 3 to which the guide casing 2A is to be seated in the rock under water, a tool for forming a seating hole having a bit formed inside and outside, respectively, is used. The outer bit protrudes outward to form a seating hole (3) having a relatively large diameter, and when the reverse rotation is made of a structure that is easily removed from the seating hole (3) as the protruding outer bit is closed inward As a result, as shown in FIG. 8, a seating hole 3 having a suitable diameter and depth of the guide casing 2A is formed.

(3) Guide casing installation step (S300)

This step is a step of seating by lowering the guide casing (2A) to the seating hole (3) formed in the seating hole shape step (S200), as shown in Figure 8 forming a seating hole (3) The guide casing 2A is placed on the upper part of the seating hole 3 by lowering the guide casing 2A along the outer circumferential surface of the tool, and then the tool is rotated in a reverse direction to lift the protruding outer bit inward. (2A) is lowered and one end of the guide casing (2A) is installed in the seating hole (3), whereby the guide casing (2A) guides the withdrawal path of the drill bit (2B) and the tubular body (10) to be described later. do.

(4) explosive charge forming step (S400)

In this step, after the guide casing 2A is seated in the seating hole 3 by the above process, the drill bit 2B is inserted into the guide casing 2A as shown in FIG. As a step of drilling the explosive charge hole (4), at this time by supplying compressed air with water to the drilling bit (2B) to remove the rock crushed material due to rock drilling, so that the drilling operation is made.

(5) blasting structure installation and fixing step (S500)

In this step, after the explosive charge hole 4 is drilled to the appropriate depth by the explosive charge hole forming step S400, the explosive charge hole 4 is removed along the guide casing 2A along the guide casing 2A. Inserting and installing the blasting structure 5 according to the present invention.

The present invention varies the installation method according to the drilling depth of the explosive charge (4), first, when the drilling depth of the explosive charge (4) is shallow to a certain depth (about 4m) or less, the upper and lower caps 20A on the barge , 20B) and inserted into the guide casing 40 in the state of assembling the blasting structure consisting of the charge portion 30 and the color portion 40, the tube 10 using a long rod, etc. After pressing the upper part of the explosive charge hole 4 so as to be inserted completely, and confirming that the blasting structure is correctly inserted in the explosive charge hole 4, the wire 13 is pulled to the outside of the lower cap 20B. By removing the sleeve 12 surrounding the leaf spring (S) in the plurality of leaf springs (S) is in close contact with the inner wall of the explosive charge hole (4) while the free end is extended outward by the elastic force, thereby the tube ( 10) is not injured by buoyancy and the inside of the explosive loader 4 Precisely fixed position.

On the contrary, when the drilling depth of the explosive charge hole 4 is deeper than a certain depth, the weight of the tubular body 10 is heavy, and thus it is difficult to handle it. It is not easy to push the upper part of the explosive charge hole 4 inside. Therefore, in this case, the tubular body 10 is prepared to have a length enough to extend from the explosive charge hole 4 to protrude above the water surface, and then the leaf spring S and the sleeve 12 are attached to the lower end of the tubular body 10. The lower cap 20B and press the tubular body 10 with the lower end sealed to the explosive charge hole 4, and then pull the wire 13 to cover the sleeve spring S. ), The tube body 10 is fixed to the inside of the explosive charge hole 4 by the leaf spring (S).

Then, the filling part 30 containing explosives is filled in the inside of the tubular body 10 and placed in the lower part of the tubular body 10, and filled with sand or the like to form the color part 40 by filling the upper part thereof. The upper cap 20A is used to seal the upper part of the tubular body 10, so that the tubular body 10 is more precisely inside the explosive-loading hole 4 even when the explosive-loading hole 4 is deep. Effective insertion can be installed.

(6) blasting step (S600)

In this step, once the blasting structure is correctly inserted and fixed in the explosive charge hole 4, the guide casing 2A is removed, the barge 1 is moved to a safe position, and then the detonation wire connected to the charge part 30 is provided. The explosives inside the structure are exploded using (C), whereby the rock in the water is broken.

On the other hand, in the above detailed description and drawings, only the detonation primer 31 is installed inside the blasting structure, so that the explosives of some explosives are exploded by the action of the detonation detonator 31, so that the entire explosive is exploded. Otherwise, the explosives 32 installed inside the blasting structure are connected by a detonation line (not shown), and then the depletion line is reconnected with the detonation primer 31 (not shown), thereby acting on the detonation primer 31. It is desirable to be able to more reliably prevent some explosives from exploding by exploding at the same time.

As described above, since the explosives can be fixed to the explosives loader formed in the rock under water by using the blasting structure, the occurrence of dead pressure is prevented, so that the explosive work can be safely and efficiently used while using the explosives. It can be done with

Claims

A pipe-shaped tube body 10 having an upper and lower portion open;

Upper and lower caps 20A and 20B installed at upper and lower portions of the tube body 10 to seal the tube body 10;

Is inserted into the inner lower portion of the tubular body 10, the charge portion 30 is received explosives;

Filled in the inner upper portion of the tubular body 10 is made of a full-color portion 40 to cover the charge portion 30,

A plurality of leaf springs (S) is installed on the outer circumference of the lower cap (20B), the leaf spring (S) by the wire 13 while wrapping the leaf spring (S) on the outside of the leaf spring (S) Underwater blasting structure, characterized in that a sleeve (12) is removed from the installation.
The method according to claim 1,

Through holes 22 are formed in the upper cap 20A, and through the through holes 22, the detonation cable C connected to the detonator primer inside the tubular body 10 is drawn out to the upper portion,

Underwater blasting structure, characterized in that the heat shrink tube (T) is installed on the outer peripheral surface of the detonation cable (C).
The method according to claim 1,

The sleeve 12 is made of Teflon material or a structure for underwater blasting, characterized in that a plurality of guide protrusions (12A) is formed on the inner circumferential surface.
The method according to claim 1 or 2,

The tubular body 10 is an underwater blasting structure, characterized in that the synthetic resin material made of PVC or PE.
The method according to claim 1 or 2,

Underwater blasting structure, characterized in that the adhesive is applied between the upper and lower caps (20A, 20B) and the tube (10).
A preparation step (S100) of fixing the barge 1 provided with the perforator 2 at the sea of the work site;

A seating hole forming step (S200) of forming a seating hole (3) on which a guide casing (2A) is seated on a rock in the water by using the perforator (2);

A guide casing installation step (S300) for seating the guide casing (2A) in the seating hole (3);

An explosive charge-hole forming step (S400) for inserting a perforation bit (2B) into the guide casing (2A) to drill the explosive charge-hole (4) of a predetermined depth in the rock;

After removing the drilling bit (2B), the blasting structure is provided with a charge portion 30 therein along the guide casing (2A) and the leaf spring (S) and the sleeve 12 is provided at the bottom After seating in the hole (4), the end of the leaf spring (S) is extended by pulling the wire (13) connected to the sleeve 12 to remove the sleeve 12 to the explosive charge hole (4) Installing and fixing the blasting structure for fixing the blasting structure (S500);

Underwater using an underwater blasting structure, comprising a blasting step (S600) of exploding explosives using the detonation wire (C) connected to the charge portion 30 in a state where the guide casing (2A) is removed from the water Blasting method.
The method according to claim 6,

When the drilling depth of the explosive charge hole 4 is a predetermined depth or less, the blasting structure is the tubular body 10, the upper and lower caps (20A, 20B), the charge portion 30 and the color portion 40 is completely assembled It is installed inside the guide casing 40 in an integrated state,

When the drilling depth of the explosive charge hole (4) is more than a predetermined depth, the explosive sheet in the state that the lower cap (20B) attached to the leaf spring (S) and the sleeve 12 is installed at the lower end of the tubular body (10) Push the wire (4), and then pull the wire 13 so that the tubular body 10 is fixed to the inside of the explosive charge hole (4), and then the charge portion 30 in the tubular body 10 Filling is located on the lower side of the tube body 10, the chromosome portion 40 is formed on the upper portion of the charge portion 30, and then the blasting by sealing the upper portion of the tube body 10 with the upper cap (20A) Underwater blasting method using a structure for underwater blasting, characterized in that the structure is installed inside the guide casing (40).
The method according to claim 6,

The sleeve 12 is made of Teflon material or underwater blasting method using an underwater blasting structure, characterized in that a plurality of guide projections (12A) is formed on the inner circumferential surface.
The method according to claim 7,

Through holes 22 are formed in the upper cap 20A, and through the through holes 22, the detonation cable C connected to the detonator primer inside the tubular body 10 is drawn out to the upper portion,

Underwater blasting method using an underwater blasting structure, characterized in that the heat shrink tube (T) is installed on the outer circumferential surface of the detonation cable (C).