JP3073277B2 - Excavation method for steel tower foundation holes - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for excavating a steel tower foundation hole or the like.

[0002]

2. Description of the Related Art For example, in order to build a power transmission tower, a foundation hole is excavated. Conventionally, as shown in FIG. 6 of the accompanying drawings, a solid rock G
In general, explosives such as dynamite D are exploded to crush and excavate.

However, in this conventional method,
This is an ad hoc operation in which the blasting occurs when the rock strikes the rock during the excavation operation, so that the operation efficiency is low and it takes time.

[0004]

SUMMARY OF THE INVENTION Therefore, the present invention
It proposes a new method that can efficiently excavate holes in a short time by arranging explosives at the position of the hole to be excavated before digging the hole, crushing it by blasting in advance, and then removing debris. .

[0005]

That is, the present invention provides:
A hollow shaft was formed substantially at the center of the hole to be excavated, and a tube loaded with a plurality of explosives was buried outside the shaft in a substantially annular shape on the inner and outer peripheries as necessary. A cutout window that opens toward the shaft is formed in the body, and each of the explosives is arranged at a position corresponding to the cutout window. The present invention relates to a method for excavating a steel tower foundation hole or the like, characterized in that when it is arranged on the inner and outer peripheries, it explodes sequentially from the inside, and thereafter, the hole is excavated by removing the debris in the blasted excavation hole.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a sectional view showing an example of an excavating method of the present invention, FIG. 2 is a plan view thereof, and FIG. FIG. 4 is a top view of FIG. 3, and FIG. 5 is a sectional view taken along line 5-5 in FIG.

As shown in FIG. 1, in the method of the present invention, first, a hollow shaft 11 is formed substantially at the center of a portion S to be excavated. The hollow shaft 11 guides an explosive explosive described later toward the center, and has a diameter of about 20 to 30 cm.
It is formed with a length substantially equal to the depth of the hole.

Next, a plurality of explosive-loaded tubes 20, 20, 20,...
Are buried in a substantially annular shape. The tube is formed on the inner and outer peripheries as needed, as shown in FIGS. In the figure, reference numeral 20 denotes a pipe in the inner peripheral row, and 21 denotes a pipe in the outer peripheral row.

Each pipe body 20 (21) is made of, for example, an iron pipe or a plastic pipe valve, and has cutout windows 25, 25, 25,.
The explosive 30 is arranged at a position corresponding to the cutout window. When the pipe is buried in the soil, the cutout window 25 is disposed so as to open toward the shaft 11 at the center of the predetermined hole S. In the figure, reference numeral 31 denotes a fuse for the explosive 30 such as dynamite, and 35 denotes a detonator. Reference numeral 29 in the top view of FIG. 4 is a mark indicating the position of the window provided on the upper part of the tube.

Further, as can be better understood from FIG. 5, in order to dispose the explosive 30 inside the cutout window 25 in the tubular body 20 (21), a filler 40 such as sand or mortar or plastic is used. It is recommended to fix with. In the embodiment, the explosive 3 is made of epoxy resin.
0 is fixed.

When the pipes 20 (21) are buried and arranged, a boring survey is carried out in advance to the underground of the predetermined hole, whereby the number and arrangement of the pipes, the number of explosives arranged in the pipes and their positions, etc. And it is advantageous to insert and arrange a tube loaded with explosive into the borehole.

After the tube is disposed, the explosive in the tube explodes. When the tube is disposed on the inner periphery and outer periphery, in order to effectively explode the predetermined hole, the inner peripheral side thereof is disposed. The explosives are exploded from top to bottom and, in each tube, from the explosive arranged at the bottom. In addition, each pipe may explode from the upper side to the lower side. Such a continuous time difference explosion can be easily performed by adjusting the detonator 35 or the primer.

After the explosion of the explosive, the planned hole is formed by removing the debris in the blasted planned hole and excavating the hole.

[0014]

As described above, according to the present invention, the explosive is arranged at the position of the hole to be excavated before the hole is excavated, crushed in advance by blasting, and thereafter, the debris is removed, whereby the hole is removed. The hole can be efficiently excavated in a short time.

[0015] In particular, according to the method of the present invention, a hollow shaft is formed substantially at the center of the hole to be excavated, and a cutout window opening toward the shaft is formed outside the shaft. A tube loaded with explosives at the position corresponding to the cutout window is buried in an annular shape on the inner and outer circumferences as necessary,
And, when the explosives in each of the tubes are to be exploded sequentially from the inside when the tubes are arranged on the inner and outer peripheries, when the explosives explode, the explosions always move toward the center. Guided and capable of effective blasting.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an example of an excavation method according to the present invention.

FIG. 2 is a plan view thereof.

FIG. 3 is a front view in which a part of a tube loaded with an explosive is omitted.

FIG. 4 is a top view thereof.

FIG. 5 is a sectional view taken along line 5-5 in FIG. 3;

FIG. 6 is a sectional view showing a conventional excavation method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Hollow shaft 20 Pipe (inner side) 21 Pipe (outer side) 25 Notch window 30 Explosive

──────────────────────────────────────────────────続 き Continued on the front page (56) References JP-B-62-20357 (JP, B2) (58) Fields investigated (Int. Cl. ⁷ , DB name) E21D 1/00 E02D 27/32 E02D 27 / 42 E21D 9/00

Claims (2)

(57) [Claims] 1. A hollow shaft is formed substantially at the center of a hole to be excavated, and a tube loaded with a plurality of explosives is buried outside the shaft in a substantially annular shape on the inner and outer peripheries as necessary. A cutout window opening toward the shaft is formed in each of the pipes, and each of the explosives is disposed at a position corresponding to the cutout window. When the pipes are arranged on the inner and outer perimeters, they are sequentially exploded from the inside, and then the soil is removed from the blasted holes to be drilled and the holes are excavated to drill holes. Drilling method. 2. A method according to claim 1, wherein the explosive is fixed at a position inside the cutout window in the pipe by a filler such as sand, mortar or plastic.