JPH02101400A - Underwater demolition - Google Patents

Abstract

PURPOSE:To facilitate the setting of demolition explosives and unify demolition effect by a method wherein linear demolition explosives are arranged so as to show the shape of line or surface with respect to natural structures and/or artificial structures to detonate them. CONSTITUTION:Linear demolition explosives 1 are arranged so as to be brought into contact directly with the surface of an underwater structure, to which foreign substances are adhered, or so as to be arranged along the surface of the same with a substantially constant distance. The arrangement of the demolition explosives 1 is selected freely in accordance with necessities and the explosives may be arranged in one line, in parallel lines, in reticulated arrangement and the like. Weights 4 are put on arbitrary places or fixed by strings or ropes in order to fix the arrangement of the linear demolition explosives 1. The detonation of the explosive 1 may be effected by a method wherein at least one end of the explosive 1 is detonated employing a detonating device such as an electric detonating fuse 2 or the like.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a method for removing foreign matter attached to underwater natural structures and artificial structures (hereinafter referred to as underwater structures) by using explosive impact. It is.

(Prior Art) Conventionally, a method is well known in which foreign matter adhering to underwater structures (for example, lime adhering to kelp reefs, shellfish adhering to the bottom of ships, etc.) is removed by impact with explosives.

For example, JP-A-57-144920, JP-A-48
As seen in Publication No. 32682, a method is introduced in which a detonating wire is fixed with dynamite, hydrous explosives, etc., and is detonated underwater by arranging wires or wires in parallel to form a planar surface. There is.

(Problems to be Solved by the Invention) However, with these methods, not only does it take a lot of time to fix the dynamite or hydrous explosive to the detonating wire, but the explosive may shift or come off, causing the explosion to occur underwater. There was a problem in that it became difficult to apply a uniform impact to the structure.

(Means for Solving the Problems) As a result of intensive studies on the above-mentioned problems, the present inventors have invented an underwater blasting method with excellent workability and blasting effect.

That is, the present invention provides a method for removing foreign matter adhering to underwater natural structures and artificial structures by bombardment with an explosive, in which the explosive is in the form of a single line, and This is an underwater blasting method characterized by blasting by arranging them in a linear or planar shape.

Explosives used in the present invention include a tube or hose-shaped explosive in which a hydrous explosive is filled in a synthetic resin tube such as vinyl chloride or polyethylene, and an atJJ wire in which a powdered chemical is wrapped in paper, cloth, etc. and then resin-coated. Use a single-wire type with water resistance. For example, the controlled blasting cord (Asahi Kasei product name: Coblank) as disclosed in Japanese Patent Application No. 61-99393 and the controlled blasting device (product name: Sanpex 400P) as disclosed in Japanese Patent Publication No. 53-19643. It is preferable to use

These explosives are usually made to have a length of several to several tens of meters, and when they are made into linear or planar shapes, they are cut into appropriate lengths. If it is necessary to prevent water from entering, the cut end surface may be waterproofed.

The amount of explosive used is about 40 to 300 g/m. That is, if it is less than 40 g/m, the blasting effect will be small, and it will be necessary to increase the number of gJ chemicals used, resulting in poor workability. Also, if it exceeds 300g/m,
Underwater structures that receive impact may be destroyed more than necessary.

In the underwater blasting method of the present invention, a linear explosive is placed in direct contact with the surface of an underwater structure on which foreign matter has adhered, or in a manner that it is attached to the surface at a substantially constant interval. Explosives can be freely selected as required, such as in the form of a single line, in parallel, or in a mesh.

To fix the arrangement of wire explosives underwater, it is sufficient to place weights on arbitrary locations or to secure the weights with strings or lobes.

The explosive may be detonated by using a device such as an electric detonator on at least one end of the connected explosive.

(Effects) According to the underwater blasting method of the present invention, not only is it easy to insert the explosive, but also the blasting effect is uniformly provided because the explosive is in the form of a single line.

Therefore, this is a blasting method that is suitable for kelp reef blasting.

Preferred embodiments will be described below with reference to the drawings.

(Example) Regarding examples, kelp reef blasting will be cited as a representative example.

Example 1 As shown in Fig. 1, a kelp reef (5) with several lime deposit layers (6) on its surface at a depth of 3 m was coated with Koblack ■ (FFI; 90 g/m), which was waterproofed at both ends. ) (1
) 10m long and detonated it from one end with a No. 6 detonator (2). As weights (4), 1 kg sand bags were placed every 2.5 m. The terminal surface of the linear explosive was covered with a waterproof cap.

After blasting, a nearly continuous surface separation zone approximately 50 cm wide was observed along the explosive.

Example 2 As shown in Figure 2, a linear explosive (1
) as Sanpex ■400P (Medicine M: 250g/
m) Five 2 ohm bombs were connected at 2 m intervals and detonated from one end with a No. 6 detonator (2). The connecting part is a linear explosive (1
) are stacked and fastened together, and the terminal surface of each linear explosive is provided with a waterproof cap. Incidentally, 2 kg sand bags were placed as weights (4) on each linear explosive at intervals of 5 m.

After blasting, surface separation zones were observed on the entire surface where the explosives were set.

Example 3 As shown in Figure 3, a 10m waterproof Koblank ■ (dosage: 90g/m) was placed on a kelp reef at a depth of 10mk.
The books were tied together in an eyelet pattern at 1 meter intervals, and a waterproof camp was attached to each end.

It was detonated from one end with a No. 6 detonator. In addition, the weight is 50 on the four corners.
It was fixed with a 2 kg iron block (7), and a 2 kg sand bag was placed in the depression of the bedrock.

After blasting, traces of peeling were observed on the entire surface where the explosives had been set.

[Brief explanation of the drawing]

1, 2 and 3 each show an embodiment of the invention. ■ Explosives, detonators, leg lines, sandbags, kelp reefs, sedimentary layers, iron blocks

Claims (1)

[Claims] 1) A method for removing foreign matter adhering to underwater natural structures and artificial structures by the impact of explosives, in which the explosive is in the form of a single line, and the foreign matter attached to the natural structures and artificial structures is linear or An underwater blasting method characterized by arranging it in a plane and detonating it.