JP2001280069A - Pile core material for electrolytic corrosion - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pile core material for electrolytic corrosion capable of surely making a temporary wall part in the breakage scheduled part of a reinforced concrete structure brittle in a short period. SOLUTION: This pile core material is formed of a hollow outer member sealed by upper and lower lids and a plurality of movable electrodes arranged at fixed intervals on the inner wall of the outer member. An electrolytic solution is interposed between the outer member and the movable electrodes, and a voltage is applied thereto. According to the electrolytic corrosion dissolution of the outer member inner wall, the movable electrodes approach to the outer member wall surface and partially electrolytically corrode the outer member wall surface into the shape of the movable electrode to make the pile core material brittle.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pile core material used for a temporary wall at a site where a reinforced concrete structure is to be broken,
More specifically, the present invention relates to a pile core material for electrolytic corrosion in which the pile core material is partially eroded by partial electrolytic corrosion.

[0002]

2. Description of the Related Art Conventionally, as a method of dismantling a reinforced concrete structure, a mechanical destruction method such as a rock drill or a demolition heavy machine has been used, and in special cases, destruction has been performed by explosives.
However, there are various problems in a method of dismantling a reinforced concrete structure that is exposed to earth pressure and water pressure, such as an earth retaining wall constructed underground, and has a risk of collapse due to dismantling. A prominent example of this is the shield method.

In the shield method, the vehicle starts and arrives from a shaft at a deep underground. Since a large earth pressure and water pressure act on the earth retaining wall of a deep shaft, the structure is generally made of a reinforced concrete continuous wall or a solid structure such as a mud solidified wall connected with H-section steel and solidified with soy cement. Has become. Conventionally, when launching and arriving at a shield machine from these shafts, a chemical solution for ground improvement is injected into the ground behind the retaining wall, and frozen pipes are inserted into multiple grounds to form frozen soil or frozen soil walls, etc. After the construction of protective works to prevent the collapse of the ground, the earth retaining wall was demolished manually or by heavy equipment.

[0004] However, this method has a problem that it takes considerable time and cost to improve the ground. Also, depending on the ground and depth, depending on these ground improvements, a certain strength,
In some cases, it was difficult to secure water stoppage. In addition, there is a problem in terms of safety because the improvement of the back ground involves exposing and opening the ground.

[0005] It would be economical and safe if the earth retaining wall of the shaft could be directly cut and opened by the disk cutter of the shield machine to reach the start. However, rebar and steel were buried as pile cores in the retaining wall of the shaft, and could not be cut by the cutter of the shield machine. In order to solve these problems, there has been known an earth retaining wall which can be cut by a shield machine using lime crushed stone as a coarse aggregate using a high-strength carbon fiber reinforced plastic as a pile core material instead of a reinforcing bar or a steel material. However, the high cost carbon fiber reinforced plastic of the core of the pile is expensive, and there is a problem in economy.

In order to solve the above problems, the present inventor has proposed that the construction of a reinforced concrete structure having a portion to be destroyed is easy to construct, is economical without using expensive members, is easy and reliable in a short time. In the shield method, a shaft that can be cut with the disk cutter of the shield machine or an earth retaining wall that blocks the excavation path of the shield machine is provided, and the protective method in the shaft when starting and reaching the shield method is provided. Japanese Patent Application No. Hei 11-2692 discloses a technique for dissolving a pile core material to make a temporary wall portion of reinforced concrete brittle by electrolytic corrosion for the purpose of eliminating the need and securing safety and shortening the construction period.
No. 91 discloses this.

FIG. 11 shows the above-mentioned Japanese Patent Application No. 11-269291.
FIG. 1 is a cross-sectional view showing a shaft of a shield method according to the related art described in Japanese Patent No. In this shield method, the starting shaft 50 and the reaching shaft having the temporary wall portion 110 that can be changed to a structure more fragile than the surrounding structure are constructed at the starting position and the reaching position, respectively. The reaching shaft is omitted from the drawing because it is the same as the starting shaft except that the temporary wall portion is directed to the starting shaft 50 side.
After this construction, first, the temporary wall 110 of the starting shaft 50 is weakened by the above-described anode melting, and then the starting shaft 5
From 0, the shield machine 200 is driven to cut and break the temporary wall 110. And the shield machine 200 toward the arrival shaft
When the shield machine 200 reaches the reaching shaft, the temporary wall portion 110 of the reaching shaft is weakened by the anode melting described above when the shield machine 200 reaches the reaching shaft. After that, the temporary wall portion 110 is cut and broken by the shield machine 200 and connected to the shield tunnel 210. According to this shield method, safety can be secured, protective work can be eliminated, and the construction period can be shortened by using a start / reach shaft which can be cut by the disk cutter 205 of the shield machine 200. In FIG. 11, 5 is a DC power supply, 40 is an electrolyte tank, 41 is an electrolyte delivery pump, 4a is an electrolyte inlet, 4b is an outlet, 6a and 6b are liquid feed pipes, and 23 and 2
Reference numeral 4 denotes a connection portion with a DC power supply.

FIG. 10 is a sectional view showing the pile core 1. The pile core 1 is formed by a hollow outer member 2 and an electrode member 3 loosely inserted into the outer member 2 with a space therebetween.
With the electrolyte 4 interposed between the outer member 2 and the electrode member 3, a voltage is applied between the outer member 2 and the electrode member 3 to anodic dissolve the inner wall 21 of the outer member 2. The outer member 2
The upper and lower openings are caps 25a, 25 made of an insulating member.
It is sealed with b.

The insulating layer 22 is formed so that the upper and lower ends of the outer member 2 cover the conductive material of the outer member 2.
The inner wall of the outer member 2 other than the portion where the conductive material is formed is an exposed portion where the conductive material is exposed. Such an insulating layer portion serves as an anode electrolytic corrosion preventing portion, and dissolves only the exposed portion of the conductive material in the anode. By arranging the insulating layer and the exposed portion of the conductive material alternately on the inner wall of the outer member 2 in the vertical and horizontal directions, the insulating layer is formed in a lattice shape, so that only the portion covered with the insulating layer is broken and the brittleness of the outer member 2 In addition to achieving the purpose of embrittlement, the duration of embrittlement can be shortened because partial electrolytic corrosion is performed instead of the entire electrolytic corrosion.

However, providing an insulating layer on the inner wall of the above-mentioned outer member has a problem in that coating inside the pipe is difficult.
For this reason, the outer member is made rectangular, and the insulation paint is applied to each wall surface and then welded. However, the insulation paint used for the insulation layer is poor in heat resistance and the insulation paint is damaged by heat during welding. Or the insulation layer 22 is damaged by welding heat with a pile core material connected to the upper and lower ends of the outer member 2 such as an H-section steel, and unplanned portions are electrolytically eroded and deteriorated. Was.

[0011] Further, as shown in FIG.
When the portion to be electrolytically eroded 2a is exposed inside and the insulating layer 22 is formed only in the non-electrolytically eroded portion, as shown in FIG. It is eaten, and the area becomes wide as shown in the enlarged electrolytic corrosion part 2b. For this reason, as the thickness of the outer member 2 increases, the area of the unplanned enlarged electrolytic corrosion portion 2b becomes very large according to the depth of electrolytic corrosion, the time for brittleness becomes longer, and the construction period becomes longer. There was a problem that was expensive.

[0012]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has been made in consideration of the above problems. It is intended to provide a pile core material.

It is another object of the present invention to provide a safe shield starting shaft that prevents electrolytic corrosion of a portion other than a designed breakage site.

[0014]

Therefore, the invention of claim 1 is a pile core material used for a temporary wall portion of a reinforced concrete structure at a portion to be destroyed, wherein the pile core material is a hollow sealed with upper and lower lids. And a plurality of movable electrodes provided in pressure contact with four inner walls of the outer member. A voltage is applied between the outer member and the movable electrode with an electrolyte solution interposed therebetween, and a voltage is applied to the inner wall of the outer member. The movable electrode approaches the outer member wall surface as the erosion proceeds, and the outer member wall surface is partially eroded into the shape of the movable electrode to embrittle the pile core.

According to the present invention, the movable electrode approaches the wall surface of the outer member as the electrolytic corrosion of the inner wall of the outer member progresses, and the distance between the inner wall of the outer member and the electrode that has been eroded is maintained at a constant interval.
The outer member wall surface can be partially eroded in the shape of the movable electrode. For this reason, the temporary wall portion at the site to be broken can be reliably embrittled in a short period of time.

According to a second aspect of the present invention, there is provided the pile member for electrolytic corrosion according to the first aspect, wherein the movable electrode is provided by being wound around an upper portion of a cylindrical or rectangular insulated electrode support frame. And a pressing means for pressing the lower portion of the electrode support frame against the inner wall of the outer member.

According to the present invention, the location and the number of the electrode support frames can be easily changed according to the external dimensions of the outer member and the portion to be broken. Therefore, the cost can be reduced by standardization without designing and manufacturing the movable electrode each time.

According to a third aspect of the present invention, there is provided the pile core for electrolytic corrosion according to the first or second aspect, wherein the pressing means is provided with a pressing plate for covering an upper portion of the electrode support frame, and the pressing plate is provided in the direction of the outer wall material wall. And a movable electrode mounting rod which stands on the outer wall surface and compresses and holds the pressing spring.

According to the present invention, assembly is easy because of the simple structure of urging by the pressing spring. In addition, since it has a simple structure, there is no risk of failure during the construction period.

According to a fourth aspect of the present invention, there is provided the pile core for electrolytic corrosion according to the first or second aspect, wherein the pressing means attaches a pressing plate for covering an upper portion of the electrode support frame and the pressing plate in the direction of the outer wall surface. And a mounting hook standing upright on the outer wall surface and holding the elastic member in tension. According to the present invention, it is easy to assemble and has a reduced member cost because of a simple structure that is pulled and held by an elastic material such as a rubber string.

According to a fifth aspect of the present invention, in the first aspect of the invention, the movable electrode has a balloon-shaped pressing member made of an elastic material which can be expanded by water pressure injected therein, A plate-shaped electrode made of a conductive metal material attached around the pressure member, and a plurality of electrode support frames made of an insulating material attached at regular intervals to the outer surface of the plate-shaped electrode; And the pressure member is expanded to press the lower portion of the electrode support frame against the inner wall of the outer member.

According to the present invention, the movable electrode is inserted into the outer member which is previously hollow at the four corners, and then the balloon-shaped pressing member is inflated to lower the electrode support frame so that the lower part of the outer member inner wall. The work process of attaching the movable electrode to the outer member for pressing against the substrate can be performed in one process. Further, the pressing plate can be uniformly pressed against the inner wall of the outer member.

The invention of claim 6 is the invention of claims 1, 2, 3, 4
Or the pile core material for electrolytic corrosion according to any one of 5, wherein the pile core material supplies and discharges an electrolyte solution or / and a fluid filler to a hollow outer member sealed with insulating upper and lower lids, It is characterized in that the outer member and the movable electrode are provided with a connection part to a DC power supply.

According to the invention described above, it is possible to construct a temporary wall using a pile core for electrolytic corrosion that can surely embrittle a temporary wall portion at a site where a reinforced concrete structure is to be broken in a short period of time. Electrolytic corrosion of portions other than the designed portion to be destroyed can be prevented, and a safe shield starting shaft can be provided.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to FIGS. Configurations similar to those in the description of the related art will be described with the same reference numerals.

FIG. 1 shows a pile core 1 for electrolytic corrosion according to an embodiment of the present invention, wherein (a) is a cross-sectional view, (b) is an enlarged view of a portion A of (a), and (c) is an AA of (a). It is a figure which shows the plane of the -AA plane. 1A is a hollow outer member 2 sealed with upper and lower lids 25a and 25b formed of an insulating material.
And a plurality of movable electrodes 10 provided in pressure contact with the four inner walls 2 a of the outer member 2. In this embodiment, as shown in the plan view of AA-AA in FIG. 1 (c), the outer member 2 is a rectangular pipe welded with a steel plate, and has an electrolyte inlet 4a and an outlet 4b at the upper and lower parts, and has an electrolyte solution 4b. Is connected between the outer member 2 and the movable electrode 10, and the connecting portion 23 provided on the outer member 2 connected to the anode of the DC power source 5 and the connecting portion 24 connected to the cathode of the DC power source 5 are connected to the movable electrode 10 by the wiring 24 a.
And a plurality of movable electrodes 10 are connected to each other by a conductive wire 11b, a voltage is applied, and the wall surface of the outer member 2 is partially eroded into the shape of the movable electrode 10 to make the pile core 1 brittle.

According to the present invention, the movable electrode 10 approaches the wall surface of the outer member 2 as the electrolytic corrosion of the inner wall of the outer member 2 progresses, and the distance between the inner wall of the outer member 2 and the electrode 11 that has been eroded is kept at a constant interval. In order to maintain, the wall surface of the outer member 2 can be partially eroded into the shape of the movable electrode 10. For this reason, the temporary wall portion 11 at the site to be destroyed
0 can be reliably embrittled in a short period of time.

FIG. 1B is an enlarged view of a portion A in FIG.
The state where the movable electrode 10 is attached to the outer wall material 2 is shown. The movable electrode 10 includes a strip-shaped electrode 11 made of a conductive metal material such as a copper plate wound around a cylindrical or rectangular frame-shaped insulating electrode support frame 12 and a lower portion of the electrode support frame 12 formed on the inner wall of the outer member 2. And pressing means 13 which presses against it.

As shown in FIG. 1C, the movable electrode 1
Reference numeral 0 denotes a plurality of band electrodes 11 attached to four inner surfaces of the outer member 2.
Partially erosion in the shape of FIG. 2 shows an embodiment of the movable electrode 10 in which a pressing spring 15 is used for the pressing means 13.

FIG. 2A is a sectional view of the movable electrode 10.
A strip-shaped electrode 11 made of a strip-shaped copper plate wound around an upper portion of a cylindrical electrode support frame 12 made of an insulating material; a pressing plate 14 made of an insulating material covering the upper portion of the electrode supporting frame 12; Press spring 1 for urging 14 toward outer wall material 2 wall surface
5 and a movable electrode mounting rod 13a which stands upright on the wall surface of the outer wall member 2 and compresses and holds the pressing spring 15. The movable electrode mounting rod 13 a is screwed to a lower nut 13 c of an insulating material fixed to the outer wall material 2 by bonding or the like, and is erected, and is pushed through the through hole 14 a of the pressing plate 14 so as to press the pressing plate 14. The spring 15 is compressed and fixed with the upper nut 13b to press the electrode support frame 12 against the outer wall material 2. The above pressing means 1
The member 3 is desirably made of an insulating material that does not dissolve when a voltage is applied.

FIG. 2B is a plan view of FIG. In this embodiment, the movable electrode 10 is provided with a strip-shaped electrode 11 along the outer periphery of a cylindrical electrode support frame 12, and provided with a pressing means 13 through a through hole 14 a at the center of a pressing plate 14.
In this embodiment, as the electrode support frame 12 and the pressing plate 14 are integrally formed, for example, a cap member used for a vinyl chloride tube can be used.

FIG. 3A shows another embodiment, in which the electrode support frame 12 has a rectangular frame shape. Since the pressing means 13 is the same as described above, the description is omitted. (B) is a strip electrode 1
1 is a plan view showing a configuration in which a connection terminal 11a for connecting to a cathode of a DC power supply 5 is provided at the center of four sides of a strip electrode 11 in order to connect adjacent movable electrodes 10 to each other with a conductive wire 11a. .

FIG. 4 shows an embodiment in which another pressing means 13 is used. The pressing means 13 in this form is used for the electrode support frame 12.
Press plate 14 covering the upper part of the outer wall material 2
An elastic member 16 for urging in the wall direction, and a mounting hook 16b erected on the wall surface of the outer wall member 2 for pulling and holding the elastic member 16
Consists of In this embodiment, the mounting hook 16b is fixed to the outer member 2 in advance by bonding or the like, and the elastic member 16 such as a rubber band is used.
Is connected to the mounting hook 16b, and the elastic member presser 1 is pulled while pulling the elastic member 16 through the through hole 14a of the pressing plate 14.
The movable electrode can be attached by a simple process of fixing at 6a. According to the present invention, the elastic member 16 such as a rubber cord is used.
, The structure is easy to assemble, and the member cost can be reduced.

FIG. 5 is a cross-sectional view of a pile core member 1 for electric corrosion according to still another embodiment. The balloon is made of an elastic material which is inserted into the hollow portion of the outer member 2 and can be expanded by the water pressure injected therein. Pressurizing member 17 and pressurizing member 17
And a plurality of electrode support frames 12 made of an insulating material and attached to the outer surface of the plate electrode 18 at regular intervals. Into the electrode support frame 12 by expanding the pressure member 17.
Is pressed against the inner wall of the outer member 2 so that the outer member 2
As the electrolytic corrosion of the inner wall progresses, the plate electrode 18 is
The inner wall of the outer member 2 approaching the wall and being eroded and the plate electrode 18
In order to keep the distance from the outer electrode 2 constant, the wall surface of the outer member 2 can be partially eroded in the shape of the plate electrode 18.

The upper part of the electrode support frame 12 is covered with a pressing plate 14 made of an insulating material, and attached to the plate-like electrode 18 by bonding or the like. As the electrode supporting frame 12 and the pressing plate 14 are integrally formed, for example, a cap member used for a vinyl chloride tube can be used. In addition, the plate-like electrode 1
It is desirable to use a stamper 8 for punching a portion other than a portion to be partially corroded and a portion to be bonded to the electrode support frame.

The pressure member 17 is made of an elastic member such as rubber and has a balloon shape. The pressure member 17 is provided with a pressure port 19 for injecting and pressurizing a liquid at an upper portion thereof. Inflate from. Due to the expansion of the pressure member 17, the plate-like electrode 18 arranged around the pressure member can be pressed through the electrode support frame 12 to the inner wall surface of the outer member 2 so as to keep a certain distance. For this reason, the plate-like electrode 1
8 approaches the outer member 2 and partially erodes.

FIG. 5B shows a BB plane of FIG.
The plate-like electrode 18 is attached to the upper part of the pressing member 17 so as to be hung by the bonding portion 17a, and is inserted into the rectangular outer member 2 without completely expanding.

According to the present invention, the movable electrode is inserted into a hollow outer member by welding the four corners in advance, and then the balloon-shaped pressing member is expanded to lower the electrode support frame to the outer member inner wall. The work process of attaching the movable electrode to the outer member for pressing against the substrate can be performed in one process. Further, the pressing plate can be uniformly pressed against the inner wall of the outer member.

Next, the progress of electrolytic corrosion using the movable electrode 10 of the pile core 1 for electrolytic corrosion of the present invention will be described with reference to FIG.

FIG. 6 (a) shows a partial cross section of the core member of the pile for electrolytic corrosion before the start of electrolytic corrosion.
Is installed. A portion 2a between the movable electrodes 10, 10 is a portion to be electrolytically eroded by the strip electrodes 11, 11. An electrolytic solution is injected into the pile core 1 for electrolytic corrosion, and an anode is connected to the outer member 2 and a cathode is connected to the strip-shaped electrode 11. When a voltage is applied, the outer member 2 is subjected to electrolytic corrosion. FIG. 6B shows a state in which the electrolytic corrosion has progressed. The movable electrode 10 is pressed by the pressing means 13.
Is urged by the outer member 2, the lower portion of the electrode support frame 12 sinks with the progress of the electrolytic erosion of the portion to be electrolytically eroded 2, and brings the strip electrode 11 closer to the portion to be electrically eroded 2 a of the outer member 2. For this reason, only the portion to be subjected to electrolytic corrosion can be efficiently melted and embrittled.

Next, an embodiment of a shaft using the pile core material for electrolytic corrosion of the present invention will be described with reference to the drawings. FIG. 7A is a plan view of a shaft 50 provided with a temporary wall 110 using the pile core 1 for electrolytic corrosion of the present invention. Since the shaft 50 is an embodiment constructed for an experiment, the periphery of the shaft 50 is a steel sheet pile and is reinforced with a beam 103. (B) is a front view which shows the pile core material of a temporary wall part. The pile core 1 for electrolytic corrosion is used by being joined to the pile core of the H-section steel 101 by bolting or the like at the joint 102 so that the pile core 1 is located at a height within the range of the outer diameter of the excavator of the shield machine.

FIG. 8A shows that the shaft machine 20 is mounted on the shaft 50.
It is a side view which shows the state which installed 0. Temporary wall 110
A wellhead 11 is provided at the launching port of the shield machine 200 inside. (B) is a front view of (a).

[0043]

According to the present invention, the following effects can be obtained.
According to the invention of claim 1, the movable electrode approaches the outer member wall surface as the electrolytic corrosion of the inner wall of the outer member progresses, and the distance between the inner wall of the outer member and the electrode that has been eroded is kept at a constant interval. The wall surface can be partially eroded in the shape of a movable electrode. For this reason, the temporary wall portion at the site to be broken can be reliably embrittled in a short period of time.

According to the second or third aspect of the present invention, the location and the number of the electrode support frames can be easily changed according to the external dimensions of the outer member and the portion to be broken. Therefore, the cost can be reduced by standardization without designing and manufacturing the movable electrode each time.

According to the fourth aspect of the present invention, the movable electrode is inserted into an outer member having a hollow shape by welding four corners in advance.
In order to inflate the balloon-shaped pressing member and press the lower part of the electrode support frame against the inner wall of the outer member, the operation process of attaching the movable electrode to the outer member can be performed in one step. Further, the pressing plate can be uniformly pressed against the inner wall of the outer member.

Further, according to the present invention, it is possible to construct a temporary wall using a pile core for electrolytic corrosion, which can surely embrittle a temporary wall portion at a site where a reinforced concrete structure is to be broken in a short period of time. In addition, it is possible to prevent electric erosion of a portion other than the planned destruction expected portion, and to provide a safe shield start reaching shaft.

[Brief description of the drawings]

FIG. 1A is a cross-sectional view of a pile core material for electrolytic corrosion of the present invention,
(B) is an enlarged sectional view of a portion A of (a), and (c) is a plan view of AA-AA of (a).

FIG. 2 shows a movable electrode according to an embodiment of the present invention;
(A) is a sectional view, and (b) is a plan view.

FIG. 3 shows a movable electrode according to another embodiment of the present invention;
(A) is sectional drawing, (b) is a top view which shows the electrode of (a).

FIG. 4 is a sectional view of a movable electrode according to another embodiment of the present invention.

FIG. 5A is a cross-sectional view showing the inside of an electrolytic corrosion pile core material according to another embodiment of the present invention, and FIG. 5B is a plan view of a BB portion of FIG.

6A and 6B are cross-sectional views showing the progress of electrolytic corrosion of the pile core material for electrolytic corrosion of the present invention, wherein FIG.

FIG. 7A is a plan view of a vertical shaft 50 provided with a temporary wall 110 using the pile core 1 for electrolytic corrosion of the present invention, and FIG. 7B is a front view showing the pile core of the temporary wall.

FIG. 8A is a side view showing a state where the shield machine 200 is installed in the shaft 50, and FIG. 8B is a front view of FIG.

9A and 9B are cross-sectional views showing the progress of electrolytic corrosion of a conventional pile core material for electrolytic corrosion, in which FIG. 9A shows the start of electrolytic corrosion and FIG. 9B shows the end of electrolytic corrosion.

FIG. 10 is a cross-sectional view of a conventional pile core for electrolytic corrosion.

FIG. 11 is a cross-sectional view showing a shaft of a conventional shield method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pile core material for electrolytic corrosion 2 Outer member 2a Expected electrolytic corrosion portion 2b Expanded electrolytic corrosion portion 3 Electrode member 4 Electrolyte solution 4a, 4b Electrolyte inlet / outlet 5 DC power supply 6a, 6b Liquid feed pipe 10 Movable electrode 11 Band electrode 11a Connection terminal 11b Conductor wire 12 Electrode support frame 13 Pressing means 13a Movable electrode mounting rod 13b Upper nut 13c Mounting screw 13d Lower nut 14 Pressing plate 14a Through hole 15 Pressing spring 16 Elastic material 16a Elastic material pressing 16b Mounting hook 17 Pressing member 18 Plate electrode 19 Pressing port 25a, b Lid 50 Vertical shaft 110 Temporary wall part 101 H-section steel 102 Joint 103 Beam 104 Bottom plate 111 Wellhead concrete 200 Shield machine

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yasuhiro Arakawa 2nd Sanbancho, Chiyoda-ku, Tokyo Tobishima Construction Co., Ltd. F-term (reference) 2D054 AC01 BA03 EA07

Claims (6)

[Claims] 1. A pile core material used for a temporary wall portion of a part of a reinforced concrete structure which is to be destroyed, said pile core material being pressed against a hollow outer member sealed with upper and lower lids and four inner walls of the outer member. Formed by a plurality of movable electrodes provided, and a voltage is applied by interposing an electrolyte solution between the outer member and the movable electrode, and the movable electrode approaches the outer member wall as the electrolytic corrosion of the inner wall of the outer member progresses. A pile core material for electrolytic corrosion, wherein a wall surface of an outer member is partially electrolytically eroded into a shape of a movable electrode to make the pile core material brittle. 2. The movable electrode includes a conductive metal strip electrode wound around an upper portion of a cylindrical or rectangular insulated electrode support frame and a lower portion of the electrode support frame pressed against an inner wall of an outer member. The pile member for electrolytic corrosion according to claim 1, wherein the core member comprises a pressing means. 3. A pressing plate for covering an upper portion of the electrode support frame, a pressing spring for urging the pressing plate in a direction of a wall surface of the outer wall, and a pressing spring standing on the wall surface of the outer wall to compress and hold the pressing spring. 3. The pile core material for electrolytic corrosion according to claim 1, comprising a movable electrode mounting rod. 4. The pressing means includes a pressing plate that covers an upper portion of the electrode support frame, an elastic material that urges the pressing plate in the direction of the wall surface of the outer wall, and an erect member that is erected on the wall surface of the outer wall and pulls and holds the elastic material. 2. A mounting hook comprising:
Or the pile core material for electrolytic corrosion according to 2. 5. The balloon according to claim 1, wherein the movable electrode is a balloon-shaped pressing member made of an elastic material which can be expanded by water pressure injected therein, and a conductive metal plate-like electrode attached around the pressing member. And a plurality of electrode support frames made of an insulating material attached at regular intervals to the outer surface of the plate-shaped electrode, inserted into the hollow portion of the outer member, and expanded the pressing member to expand the electrode support frame. The pile member for electrolytic corrosion according to claim 1, wherein the lower portion is pressed against the inner wall of the outer member. 6. The pile core material includes an inlet / outlet for supplying / discharging an electrolyte solution and / or a fluid filler to / from a hollow outer member sealed by upper and lower lids, and a connection portion between the outer member and the movable electrode to a DC power supply. Claim 1 characterized by comprising:
The pile core material for electrolytic corrosion according to any one of 2, 3, 4, and 5.