JP2001140477A - Method for demolishing concrete structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance efficiency of a demolishing work of a concrete structure. SOLUTION: To demolish a concrete structure having a skeleton 12 covered with a finish layer 14, a plurality of first holes 22 are formed in the finish layer 14 to such an extent as to reach the surface of the skeleton 12, and second holes 24 are formed in both the finish layer and the skeleton to an extent so as to reach a reinforcement 20 in the skeleton. Then, direct current is applied to the skeleton via the surface 13 of the skeleton exposed to the first holes and the reinforcement 20 exposed to the second holes, respectively. Thus, degraded areas 40 which are sequentially connected together, in a manner of making contact with the skeleton or partially superposing on each other, are generated. Thereafter, third holes 42 are formed in the degraded areas 40 of the skeleton to be connected to the first holes, and an expanding agent is fired into the third holes.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for dismantling a concrete building, and more particularly, to a method for destroying a building covered with a finishing layer of a concrete building.

[0002]

2. Description of the Related Art Conventionally, in order to destroy a skeleton of a concrete building, a weak DC current is applied to the skeleton through the surface of the skeleton and a reinforcing bar in the skeleton, thereby deteriorating a part of the skeleton. That is being done. The rebar is used as a positive electrode for energization, and a negative electrode assembly is disposed on the surface of the skeleton. The negative electrode assembly includes a container having an open end surface in contact with the frame, an electrolyte contained in the container, and an electrode plate immersed in the electrolyte.

[0003] According to this, a part of the deteriorated skeleton is more fragile than before the deterioration, so that it can be easily broken.

[0004] Further, it has been proposed that the conventional body is destroyed by making a plurality of holes in a deteriorated area and filling the holes with an expanding agent. According to this, a large number of cracks are generated in the fragile portions between the holes due to the expansion pressure on the peripheral wall surface of the holes due to the volume expansion of the expanding agent over time, and the deteriorated region is statically crushed.

When the surface of the skeleton is covered with a finishing layer such as a mortar layer, the finishing layer is crushed and peeled off to expose the surface of the skeleton to energize the skeleton. It is possible. However, this requires time and labor and reduces the efficiency of the frame destruction work. Also, the replenishment work of the electrolytic solution leaking from between the open end face of the container for the electrode plate and the finishing layer, etc., also causes a reduction in the efficiency of the work of breaking down the skeleton.

[0006]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to improve the efficiency of demolition work of a concrete building.

[0007]

SUMMARY OF THE INVENTION The present invention is a method of dismantling a concrete building having a skeleton covered with a finishing layer, wherein the finishing layer has a plurality of first holes reaching the surface of the skeleton. Drilling, and drilling a second hole in both the finishing layer and the skeleton to reach a reinforcing bar in the skeleton;
Passing a direct current to the skeleton through the surface of the skeleton and the rebar exposed to the first and second holes, respectively;
Forming a degraded region in contact with or partially overlapping with the skeleton, and thereafter, forming a third hole continuous with the first hole in the degraded region of the skeleton, and expanding agent in these third holes; Filling.

[0008] The swelling agent may be further filled in a first hole connected to the third hole.

[0009] A container having an open side surface to which a flexible sealant in contact with the finishing layer is attached for supplying electricity to the skeleton, wherein the electrolyte fills the plurality of first holes, and A container housing the electrode plate immersed in the container can be arranged.

[0010]

According to the present invention, the first hole is formed in the finishing layer covering the surface of the skeleton to expose the surface of the skeleton for energization, and the first hole is formed through the first hole. By applying a current to the skeleton, a degraded region which is in contact with each other or partially overlaps and continues can be obtained. For this reason, it is not necessary to crush and remove the finishing layer, thereby making it possible to quickly and efficiently perform the work required for breaking the skeleton.

[0011] The frame can be crushed quietly and without any special labor due to the generation of cracks in the portion between the third holes due to the volume expansion effect of the expanding agent over time. Further, the first expanding agent is connected to the first hole connected to the third hole.
When filling the holes, the volume expanding action of the expanding agent is also exerted on the portions between the first holes, and the crushing of the finishing layer can be performed at the same time. The dismantling work can be made more efficient.

[0012] The container for accommodating the electrode plate and the electrolytic solution connected to the surface of the skeleton has an open side surface to which a flexible sealant in contact with the finishing layer is attached. The sealing material on the open side is closely contacted with the surface of the finishing layer following the unevenness of the surface of the finishing layer, thereby preventing leakage of the electrolytic solution from between the opening side of the container and the finishing layer and interruption of the energization due to the leakage. Thus, it is possible to realize a more efficient demolition of a concrete building.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, a reinforced concrete frame composed of pillars and walls forming part of a concrete building 10 (only a part thereof is shown) to be demolished according to the present invention. 12 is shown.

Both surfaces 13 of the body 12 are each provided with a finishing layer 14, for example, a mortar layer 16,
Is covered with a wallpaper 18 adhered to. The frame 12 may be one in which only one surface is covered with the finishing layer 14. The frame 12 has a plurality of reinforcing bars 20 buried in the inside thereof extending vertically.

In applying the disassembly method according to the present invention, first, a plurality of holes (first holes) 22 reaching each surface 13 of the skeleton 12 are formed in the finishing layer 14, and both the finishing layer 14 and the skeleton 12 are formed. After these, the reinforcing bars 20 in the frame 12
(Second hole) 24 is reached. The surface of the skeleton 12 where the first hole 22 is formed may be, for example, in the case of a skeleton formed of a wall, either the entire region of the wall surface or a partial region thereof.

By drilling the first and second holes 22, 24, a part of the surface 13 of the skeleton and a part of the reinforcing bar 20 are exposed in these holes, respectively.

The formation of the first hole 22 makes it unnecessary to crush and remove the finishing layer 14 for energizing and forming a deteriorated region described later.

The arrangement of the plurality of first holes 22 can be, for example, staggered (see FIG. 2). The first and second holes 22, 24 can be formed using a drill device (not shown) such as an ultrasonic drill.

Next, a weak DC current is passed through the skeleton 12 through a part of the surface 13 of the skeleton exposed in the first and second holes 22 and 24 and a part of the reinforcing bar 20. To this end, an electrode plate (cathode plate) 26 is arranged, and the reinforcing bar 20 is connected to the positive electrode 2.
8 is assumed.

The cathode plate 26 is made of a wire mesh. Cathode plate 26
Is arranged in a container 30 fixed to the finishing layer 14,
The plurality of first holes 22 are open to the surface of the finishing layer 14.

The cathode plate 26 has an open upper end 36 described later in the container 30.
Through a cable 31 extending through the
Are respectively connected to a DC power supply (not shown) via a cable 32 extending in the second hole 24.

The container 30 on which the cathode plate 26 is disposed is formed of a flat box-like body made of a plastic material such as a vinyl chloride resin, and has an open side surface 34 facing the surface of the finishing layer 14 and an open upper end. 36.

A strip-shaped sealing material (not shown) extending along the open side 34 of the container 30 is attached by bonding.

The sealing material is made of, for example, hard rubber and has flexibility. In the illustrated example, an adhesive (not shown) is applied to the surface of the sealing material, and the container 30 is liquid-tightly fixed to the surface of the finishing layer 14 via the adhesive.

Thus, the container 30 cooperates with the surface of the finishing layer 14 to define a storage space for the electrolyte described later.
The flexible sealing material deforms following irregularities on the surface of the finishing layer 14 and comes into close contact therewith, so that higher liquid tightness can be imparted.

The container 30 contains an electrolyte 38 such as a magnesium chloride solution as an oxidation promoter supplied from its open upper end 36 and supplied as needed.

The entire cathode plate 26 in the container 30 is immersed in the electrolyte 38. Each of the first holes 22 is filled with the electrolyte 38, and the surface 13 of the frame 12 is
It touches 8. For this reason, the cathode plate 26 is connected to the surface 13 of the frame 12 via the electrolyte 38, and
8 penetrates from the surface of the frame 12 to the inside.

Next, a direct current is passed from the power source to the frame 12 through the cathode plate 26 and the positive electrode 28, and a portion of the frame 12 (more specifically, a portion between the reinforcing bar 20 and each first hole 22) is formed. ). As a result, a large number of small cracks are formed in the part of the frame 12 due to the expansion accompanying the progress of corrosion of the reinforcing bar 20 due to the electrolysis of the electrolytic solution 38 permeated into the frame 12 and the pressure of oxygen generated during the electrolysis. This causes a part of the frame 12 to deteriorate.

That is, a plurality of deteriorated areas 40 (shown by imaginary lines in FIG. 2) which are more vulnerable than other parts (healthy parts) are generated. The generally cylindrical fragile portion extending from each reinforcing bar 20 to the finishing layer 14 can be easily broken with a smaller force than the sound portion.

The energization is, for example, 10 cm in width as seen in FIG.
This is performed by applying a current of 0.6 to 1.0 A / m under a voltage of 50 V for 7 to 14 days.

These deteriorated areas 40 are partially overlapped with each other or connected to each other. The manner in which the deteriorated regions 40 are connected to each other or the radius of the deteriorated region can be changed by changing the diameter of the first holes 22, the mutual interval between the first holes 22, the magnitude of the applied current, and the like.

After the degraded area 40 is created, the electrode plate 26
Then, the container 30 is removed, and a hole (third hole) 42 (only one of which is indicated by an imaginary line) is formed in each of the deteriorated areas 40. The hole 42 can be formed by inserting the drill from the first hole 22 and cutting the frame 12.

Thereafter, an expanding agent (shown) is filled from the first hole 22 to the third hole 42. The swelling agent is preferably made by kneading a drug mainly composed of an inorganic compound mainly composed of quick lime and silicate (for example, "Blystar" manufactured by Onoda Co., Ltd.) with water and kneading the mixture. Reacts with water (hydration reaction) so that its volume expands with time.

Other examples of the expanding agent include calcined dolomite type, magnesia type, ordinary Portland cement-blast furnace slag-bauxite-gypsum type, alumina cement-lime-gypsum type and the like.

Due to the volume expansion of the expanding agent in each of the holes 42, the peripheral wall surface of the hole 42 receives a radial expansion pressure. Said "Blyster" has a volume expansion of about three times. Due to the volume change of the expanding agent, a crack extending from one hole 42 to the other hole 42 is formed in the inter-portion of the third holes 42, that is, in the two deteriorated regions 40 around the third holes 42 adjacent to each other. (Not shown) occurs.

Thus, the frame 12 can be crushed statically and without labor. The crushed frame 12 can be destroyed together with the finishing layer 14 by applying a small force to the finishing layer 14.

By filling the third hole 42 and the first hole 22 connected to the hole with the expanding agent, the finishing layer 14 can be crushed at the same time. Destruction can be further facilitated.

[Brief description of the drawings]

FIG. 1 is a partial longitudinal sectional view of a skeleton and a finishing layer of a concrete building.

FIG. 2 is obtained by cutting out a container containing an electrolytic solution;
It is a partial front view of a finishing layer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Concrete building 12 Frame 14 Finishing layer 20 Reinforcing bar 22, 24, 42 First, second and third hole 26, 28 Cathode plate and positive electrode 30 Container 38 Electrolyte

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hirokazu Tanaka 2-1 Tsukudocho, Shinjuku-ku, Tokyo Kumagaya Gumi Tokyo Head Office (72) Inventor Nobuyuki Takahashi 2-1 Tsukudocho, Shinjuku-ku, Tokyo Stock Company Kumagai Gumi Tokyo head office F term (reference) 2E176 AA01 DD44 DD53

Claims (3)

[Claims] 1. A method of dismantling a concrete building having a skeleton covered with a finishing layer, wherein the finishing layer is provided with a plurality of first holes reaching a surface of the skeleton. Drilling a second hole reaching both sides of the skeleton in the skeleton, passing a DC current through the skeleton through the surface of the skeleton and the rebar exposed to the first and second holes, respectively, Forming a continuous deteriorated region in contact with or partially overlapping with the first hole, and then forming a third hole continuous with the first hole in the deteriorated region of the skeleton, and filling these third holes with an expanding agent. A method of dismantling a concrete building, including: 2. The method according to claim 1, further comprising: connecting the first hole to the third hole.
The method of claim 1, wherein the holes are filled with the swelling agent. 3. A container having an open side surface to which a flexible sealant in contact with the finishing layer is attached for supplying electricity to the skeleton, the electrolytic solution filling the plurality of first holes, and the electrolytic solution. The method according to claim 1, further comprising disposing a container containing the electrode plate immersed in the liquid.