JP2013087413A - Demolition method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a demolition method that improves the operability of demolition work for a concrete structure.SOLUTION: In a section 11 in which a concrete structure 1 is to be parted, a parting plane 3 and a parting plane 7 in a long-axis direction are set crossing each other. Concrete 2 is bored to form a plurality of hole parts 5 in the parting plane 3 and a plurality of hole parts 9 in the parting plane 7 in a long-axis direction, respectively. Linear explosives 19 are installed the hole parts 5 and hole parts 9, and blasting is carried out. After the blasting, the concrete structure 1 has formed a through crack 27 at the position of the parting plane 3 and a through crack 29 at the position of the parting plane 7. Further, V-grooved blasting parts 33, 35 are formed at the positions of a side end 6 of the parting plane 3 and a side end 8 of the parting plane 7, respectively. Then tie hoops 15 exposed at the blasting parts 33, 35 are cut off, and the parted member 4 is separated, crushed, and removed in order.

Description

  The present invention relates to a dismantling method.

  Conventionally, as a method for dismantling a concrete structure, there is a method of (1) dismantling using a large breaker and a concrete crusher. In the method (1), a member of a reinforced concrete structure (hereinafter referred to as an RC structure) can be crushed into a glass shape relatively efficiently and separated from the reinforcing bar for dismantling.

  Further, when a member having a large cross section or the like cannot be grasped by a crusher, (2) there is a method of providing holes at regular intervals by core boring and disassembling using a crusher. In the method (2), holes are provided using core boring at intervals according to the opening width of the crusher, and the holes are gripped and disassembled by the crusher.

  Further, (3) there is a method of disassembling using a diamond cutting method such as a disk blade or a wire saw. If the method of (3) is used, the member of the large cross section which a crusher cannot chew can be cut | disconnected in a block shape, suppressing scattering of a concrete piece. A construction method using low noise and low water has also been developed.

In addition, (4) there is a method in which an explosive is loaded into a structure and dismantled using a controlled explosion that partially blasts the member. In the method of (4), in a member such as a column or a beam, one to several holes are opened at a place to be crushed, the explosive is charged and blasted, and concrete is crushed at the place (for example, Patent Document 1). To Patent Document 3).
In addition, Patent Document 4 includes (5) an example of using a shaped explosive using the Neumann effect as a method of disposing an explosive and cutting a member, and mentions application to a floor slab or the like.

Japanese Patent Laid-Open No. 2003-307038 JP 2004-293260 A JP 2005-179924 A JP 2007-16432 A

However, when the concrete structure is demolished by the method (1), large noise, dust, and vibration are generated. Vibration occurs when large and large cross-section members such as deep foundation piles and pillars are split with a large breaker, or when steel reinforced concrete structures (hereinafter referred to as SRC structures) containing steel frames are disassembled with a breaker. And the noise problem is even greater.
In the method (1), a space for operating heavy machinery is required. For this reason, in particular, when there is no space to operate large heavy machinery in dismantling work in a narrow area or in the underground part where there are many main piles and horizontal beams, small heavy machinery is used, and work efficiency Falls to the extreme.
Furthermore, in the method of (1), when dismantling the above-ground part and the underground part, if the above-ground part has not been disassembled, heavy machinery cannot enter the underground part. It cannot be performed in parallel and it is difficult to shorten the process.

  In the method (2), since a hole is provided using core boring, a lot of work time is required. In addition, the cost is high. Furthermore, in the case of a member having a large cross section, a large number of holes are required, which is further inefficient in terms of cost and work time.

  The method (3) is expensive. In addition, it takes time to set the cutting tool, perform preliminary work for cutting (in the case of a wire saw, core boring is required to pass the wire through the underground wall and foundation beam) and cutting. In addition, when a member having a large cross section is cut with a disk blade, it is necessary to use a large blade. However, it takes time to set up the machine, and the amount of uncut parts increases, resulting in a reduction in work efficiency.

  In the method of (4), when blasting is performed by making one to several holes in a place to be crushed, generally a drill with a diameter of about 30 to 50 mm is necessary, and there is a possibility of interfering with a reinforcing bar or the like at the time of drilling. Get higher. In addition, during the blasting, loud explosions, vibrations, and blasts are generated, which increases the influence of nearby noise and the like. Furthermore, the problem of cost and the like is that the curing measures applied to the blasted portion to prevent dust and the like from being scattered become large, such as stacking a metal mesh curing on the explosion-proof sheet.

  Furthermore, in this method, there are usually only a few charged locations per member, and the length of the explosive charged for the member cross-sectional dimension is short. Therefore, the explosion source is practically arranged in a dot shape, and the blasting form in which the concrete is crushed conically in the direction of the minimum resistance line of the member from the explosion source is unavoidable. However, in order to dismantle the concrete structure, it is not always necessary to pulverize the concrete into pieces, and it is sufficient to penetrate a crack in one section of the concrete. From this point of view, the method (4) consumes useless energy for parting, and is inefficient.

  In addition, as shown in (5), in the method using molded explosives, the explosive source is exposed to the atmosphere because the molded explosives are installed on the surface of a member such as a floor slab, and a large explosive sound or blast is generated in the air. The problem is that it propagates directly.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a demolition method that improves the workability of the demolition work of a concrete structure.

  The present invention for achieving the above-described object is a dismantling method for disassembling a columnar concrete structure, wherein a long axial hole is provided in a predetermined long axial dividing section for dividing the concrete structure. A step of arranging a plurality of explosives in the hole portion, blasting the explosive, and dividing the concrete of the concrete structure at the divided cross section while side edges of the divided cross section. And a step of forming a groove-like crushing portion on a side surface in the major axis direction of the concrete structure.

In the present invention, the groove-shaped crushing portion is formed on the side surface of the concrete structure while dividing the concrete of the columnar concrete structure along the major cross section. By forming the groove-shaped crushing part, even when reinforcing bars such as band bars are provided on the outer periphery of the concrete structure, the reinforcing bars are exposed at the crushing part, and the cutting of the reinforcing bars with a cutter or the like becomes easy. . By sequentially disassembling the finely divided members in this manner, it is not necessary to use a large heavy machine for the dismantling work.
In addition, by properly arranging multiple linear explosives in the cross-section, the energy of explosives can be used without waste, and the concrete structure can be efficiently divided and crushed by using the smallest amount of explosives. Can do. Thereby, noise and vibration can be reduced and suppressed for a moment.
As described above, the workability of the demolition work of the concrete structure is improved. Thereby, the cost concerning dismantling work can be reduced and the construction period can be shortened.

Further, the amount of the explosive disposed in the hole formed in the vicinity of the inside of the reinforcing bar on the outer peripheral portion of the concrete structure is smaller than the amount of the explosive provided in the other hole in the long-axis dividing section. It is desirable to enlarge it.
As a result, when reinforcing bars exist on the outer periphery of the concrete structure, the amount of explosive loaded in each hole is made efficient, the concrete structure is divided at the section, and the resistance to shearing by the reinforcing bars is resisted. Thus, the groove-shaped crushing portion can be reliably formed.

The concrete structure is divided into a plurality of the divided sections as necessary. Moreover, it is desirable to set the plurality of divided sections so as to intersect each other.
If it divides | segments in a several division | segmentation cross section, when dividing | segmenting a large cross-section concrete structure, the member after a division | segmentation can be made smaller and subsequent disassembly will become easier. Moreover, if it sets so that a cross section may cross | intersect, a concrete structure can be divided | segmented into a small member efficiently.

In addition, it is desirable that the interval between the adjacent side end portions is set to a size that can be grasped by a crushing device, and a member divided by the dividing section is grasped by the crushing device and crushed.
As a result, the interval between adjacent crushing parts can be made smaller than the width that can be gripped by a claw member such as a small crushing device, and the divided member can be crushed by a small crushing device or the like and disassembled. , Workability is improved.

The holes are preferably formed at intervals of about 150 mm to 500 mm.
By loading and blasting the necessary minimum amount of linear explosives in these holes, a small amount can be obtained by continuously applying tensile stress in the direction of dividing the concrete in the section by the pressure of the shock wave at the time of blasting. The concrete structure can be divided with the explosive.

The diameter of the hole is preferably about 20 mm.
In the present invention, since the necessary minimum amount of explosive is linearly arranged in the hole, the diameter of the hole can be reduced to about 20 mm. This eliminates the need for a large machine for drilling and reduces noise, vibration, dust and the like. Also, the drilling cost can be reduced. Furthermore, the possibility of interference with the reinforcing bar during drilling is reduced.

  ADVANTAGE OF THE INVENTION According to this invention, the demolition method which improves the workability | operativity of the demolition work of a concrete structure can be provided.

Perspective view of concrete structure 1 before placing a linear explosive Sectional view in the member major axis direction of the concrete structure 1 before arranging the linear explosive The figure which shows the linear explosive 19 Sectional view in the member axial direction of the concrete structure 1 after arranging the linear explosive Perspective view of concrete structure 1 after blasting The perspective view of the concrete structure 37 before arrange | positioning a linear explosive Sectional view of concrete structure 37 after placing linear explosive Perspective view of concrete structure 37 after blasting

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[First Embodiment]
First, a first embodiment of the disassembly method of the present invention will be described. 1st Embodiment demonstrates taking the case of dismantling the columnar concrete structure 1 of RC structure as shown in FIG. 1, FIG. 2 as an example.

  FIG. 1 is a perspective view of a concrete structure 1 before placing a linear explosive. FIG. 2 is a cross-sectional view in the member major axis direction of the concrete structure 1 before arranging the linear explosive. 2 is a cross-sectional view taken along line AA shown in FIG.

  Here, the concrete structure 1 is an existing pile, and as shown in FIGS. 1 and 2, the concrete structure 1 is composed of concrete 2, an axial rebar 13, a band 15, and the like. The axial reinforcing bars 13 and the reinforcing bars 15 are provided on the outer periphery of the concrete structure 1.

  As shown in FIG. 1, in the dismantling method of the first embodiment, first, a section 3 and a section 7 in the major axis direction are set in a section 11 in the major axis direction where the concrete structure 1 is to be divided. . The dividing plane 3 and the dividing plane 7 are set so as to intersect. The positions of the dividing plane 3 and the dividing plane 7 are such that the interval 10 of the linear distance between the side end 6 of the adjacent dividing plane 3 and the side end 8 of the dividing plane 7 is a small nibler or crusher to be used for dismantling. Set the size so that it can be gripped by a small crusher. That is, the interval 10 is set to be smaller than the opening width of the claw member of the crushing device.

Next, drilling is performed from the upper surface of the concrete structure 1 using a hammer drill or the like, and a plurality of holes 5 in the major axis direction are formed in the dividing surface 3 at a predetermined interval 17 as shown in FIGS. Form. Out of the holes 5, both outer holes 5 a are formed in the vicinity of the inside of the reinforcing bars (such as the reinforcing bars 15) on the outer periphery of the concrete structure 1.
Similarly, a plurality of holes 9 in the major axis direction are formed in the dividing plane 7 at a predetermined interval. Out of the holes 9, both outer side holes 9 a are formed in the vicinity of the inside of the reinforcing bars of the outer peripheral portion of the concrete structure 1.

  The perforation depth of the hole 5 and the hole 9 is set to a depth of about 2/3 of the section 11 to be divided or a depth of ((depth of the section 11) −200) mm. The diameter of the hole part 5 and the hole part 9 shall be about 20 mm. The interval 17 between the holes 5 and the interval between the holes 9 are appropriately determined according to the strength of the concrete 2 and the like, and are about 150 mm to 500 mm.

Next, a linear explosive is placed in each of the holes 5 and 9 formed in the concrete structure 1.
An example of this linear explosive is shown in FIG. The linear explosive 19 shown in the figure includes an electric detonator 21 connected to a leg wire 21a, an explosive wire 23, and the like. The linear explosive 19 is produced by fixing the electric detonator 21 and the explosive wire 23 with a tape or the like.

  The linear explosive 19 may be produced in advance at an explosives factory or the like, or may be produced at an on-site pyrotechnic site while confirming the blasting results at the site. The amount of explosive can be freely adjusted by adjusting the length and number of explosive wires 23. When producing the linear explosive 19, calculate the optimal explosive amount according to the concrete strength, cross-sectional properties such as the amount of reinforcing bars and steel frames, drilling position, dismantling method, etc. deep. In addition, when the cross section of the concrete structure to be demolished is small, only the electric detonator 21 may be provided.

  FIG. 4 is a view showing a state in which the linear explosive 19 is arranged in the hole 5 of FIG. However, the illustration of the leg line 21a and the like is omitted.

The linear explosive 19 is loaded at a position away from the opening at the upper end of each hole 5 by a predetermined distance, for example, about 200 mm away. The inclusion 25 such as sand is packed at the position of the predetermined distance from the opening, and tamping is performed at the opening of the hole 5. The said leg wire 21a is taken out of each hole part 5 for connection.
Similarly, the linear explosive 19 and the like are also disposed in the hole 9.

  In the dividing surface 3, the hole 5a formed inside the reinforcing bar on the outer peripheral portion of the concrete structure 1 is loaded with a larger amount of explosive than the other holes 5b. In the hole 5a, for example, an explosive amount about twice that of the hole 5b is loaded. The same applies to the amount of explosive disposed in the hole 9 of the dividing surface 7, and the amount disposed in the hole 9a is larger than the amount disposed in the other hole 9b, for example, about twice.

  After loading the linear explosives 19 in the holes 5 and 9 in this way, the leg wires 21a and the like are connected, and the electric detonator 21 of each linear explosive 19 is connected in series with the blasting device and the explosion-proof sheet. After covering the blasting site with etc. and curing, each linear explosive 19 is blasted. Since the amount of explosive used is kept to the minimum necessary amount, it is only necessary to cover the explosion-proof sheet.

  FIG. 5 shows a perspective view of the concrete structure 1 after blasting. Due to the pressure of the shock wave at the time of blasting of the linear explosive 19 in the holes 5 and 9, the energy of the explosive is not dispersed, and the concrete 2 is divided in the dividing section 3 and the dividing section 7 (see FIG. 1). A tensile stress acts continually on the dividing surface 3 and the dividing surface 7.

  Thus, as shown in FIG. 5, in the concrete structure 1, a through crack 27 is formed at the position of the dividing surface 3, and a through crack 29 is formed at the position of the dividing surface 7, and the concrete 2 is finely divided into four members 4. Is done. Further, at the position of the side end portion 6 of the dividing surface 3, the cover concrete on the side surface 31 in the long axis direction of the concrete structure 1 is crushed, and a V-shaped groove-shaped crushed portion 33 is formed. The cover concrete on the side surface 31 is also crushed at the position of the side end portion 8 of the dividing surface 7, and a V-shaped groove-shaped crushed portion 35 is formed.

  After the concrete structure 1 is brought into the state shown in FIG. 5 by blasting of the linear explosive 19, the strips 15 exposed to the crushing portion 33 and the crushing portion 35 are cut with a cutter or the like to separate the member 4, and the small nibbler The four members 4 are sequentially removed using a small crusher such as a crusher or a crusher.

  As described above, the distance 10 (see FIG. 1) between the side edge 6 of the dividing surface 3 and the side edge 8 of the dividing surface 7 is the opening width of a claw member such as a small nibler or a crusher used for disassembly. It is set to be smaller. Therefore, since the gap between the adjacent crushing part 33 and the crushing part 35 is smaller than the opening width, the member 4 can be easily held by holding the crushing part 33 and the crushing part 35 with a small nibler or a crusher. Can be crushed and removed. In addition, when the crack etc. have generate | occur | produced in the side surface 31 of the member 4, the cracked concrete can also be crushed and removed by grabbing the crack with a small nibler or the like.

  In the first embodiment, after the dismantling of the section 11 of the concrete structure 1 is completed, in the section below the section 11, formation of holes, installation and blasting of linear explosives are performed as necessary. The concrete structure 1 is disassembled by repeatedly separating and crushing the members.

As described above, in the first embodiment, the concrete 2 of the columnar concrete structure 1 is divided by the major cross-section 3 and the sub-section 7 while covering the long-side surface 31 of the concrete structure 1. Concrete is crushed to form groove-shaped crushing portions 33 and crushing portions 35. By forming the groove-shaped crushing part 33 and the crushing part 35, the band 15 is exposed, and the band 15 is easily cut by a cutter or the like. By sequentially removing the members 4 that have been finely divided in this manner, disassembly can be performed without using large heavy machinery.
For example, the above-mentioned dismantling method is applied to dismantling work in confined areas where work efficiency has been drastically reduced without large heavy machinery in the past, and dismantling work in underground areas where there are many parent piles and horizontal beams. By forming through cracks and crushing parts, even a small heavy machine can be easily disassembled, and work efficiency is improved. Also, even in a narrow space where only a small heavy machine did not enter and the hand was disassembled only by hanging, it is very efficient to perform the removal work manually after forming through cracks etc. Become.

  In the present embodiment, the minimum amount of linear explosive 19 is loaded and blasted into the plurality of holes 5 and 9 formed at intervals of about 150 mm to 500 mm. In this way, by properly arranging a plurality of linear explosives 19 at the dividing surface 3 and dividing surface 7, the energy possessed by the explosive can be used without waste, and the concrete structure 1 can be used with the minimum amount of explosive used. It can be efficiently divided and crushed. Thereby, compared with the above-mentioned conventional dismantling methods such as dismantling using a large breaker, noise and vibration can be reduced and suppressed for a moment.

  Furthermore, the amount of the explosive to be loaded into the hole 5a and the hole 9a formed inside the reinforcing bars such as the reinforcing bars of the outer periphery of the concrete structure 1 is set to the amount of the explosive to be loaded into the other holes 5b and 9b. By increasing the amount to about twice the amount, the amount of explosive charged in each hole is made efficient, the concrete structure 1 is divided at the section, and the crushing portion 33 resists the shear resistance of the reinforcing bar. The crushing part 35 can be formed reliably. In the case of unreinforced concrete, the amount of explosives placed in all the holes in the dividing plane may be the same.

  In addition, since the concrete structure 1 is divided into a plurality of cross sections 3 and 7 that intersect, the concrete structure 1 can be efficiently and smaller members when dismantling the large cross-section concrete structure 1. Can be divided into four.

  Moreover, in 1st Embodiment, the space | interval 10 of the side edge part 6 of the adjacent dividing surface 3 and the side edge part 8 of the dividing surface 7 is made into small crushing devices, such as a small nibler and a crusher which are going to be used for dismantling. Set to a width that can be gripped by the device. Thereby, each member 4 divided by blasting can be crushed by a small crushing device while holding the crushing portion 33 and the crushing portion 35 adjacent to each other.

  In the first embodiment, since a small amount of the linear explosive 19 is used, the hole 5 and the hole 9 can be made as small as about 20 mm. This eliminates the need for a large-scale machine for drilling, enables drilling work with a small heavy machine or a hand-held drilling instrument, and reduces noise, vibration, dust, and the like. Also, the drilling cost can be reduced. Furthermore, the possibility of interference with the reinforcing bar during drilling is reduced.

  Thus, the workability | operativity of the dismantling operation | work of the concrete structure 1 improves by using the dismantling method of 1st Embodiment. Thereby, cost can be reduced and construction period can be shortened. For example, when compared with the dismantling method that uses core boring, wire saws, and wall saws, it is estimated based on experimental results of cutting RC beams with a cross section of 1.0m x 1.0m by two workers. Then, the knowledge that both required time and cost can be reduced by about 40% was obtained.

  In addition, although 1st Embodiment demonstrated the disassembly of the columnar concrete structure 1 which is an existing pile, the case where the existing foundation pile buried underground is the same member as this concrete structure 1 Also, almost the same method can be applied.

  That is, when dismantling such an existing foundation pile, as in the first embodiment, a hole is formed by drilling from the upper surface of the pile, and a linear explosive is installed and blasted in the hole. And sever the concrete. At the time of blasting, the upper surface of the pile is cured with a rubber plate or explosion-proof sheet.

  Then, after excavating the soil around the pile, crushing the root part of the divided member, and separating the separated member by cutting the rebar exposed in the crushing part on the side of the pile by blasting the linear explosive, Remove this. This process is repeated, and piles are disassembled in order from the ground surface. As a result, the same effects as described above can be obtained, and noise generated during dismantling can be further suppressed by blasting in the soil.

[Second Embodiment]
Next, a second embodiment will be described. In the second embodiment, a case where a part of a columnar concrete structure 37 having an SRC structure as shown in FIGS. 6 and 7 is disassembled will be described as an example.

  FIG. 6 is a perspective view of the concrete structure 37 before arranging the linear explosive. FIG. 7 is a cross-sectional view of the concrete structure 37 after arranging the linear explosive. 7A is a cross-sectional view in the member plane direction along the line BB shown in FIG. 6, and FIG. 7B is a cross-sectional view in the member major axis direction along the line CC shown in FIG.

  Here, the concrete structure 37 is an existing pillar of the SRC structure on the outer periphery of the underground provided continuously in a beam shape. As shown in FIGS. 6 and 7, the concrete 38, the axial rebar 43, the band reinforcement 47, H-shaped steel 45 and the like. The H-shaped steel 45 is provided at the center of the pillar portion of the concrete structure 37, and the axial rebar 43 and the strip 47 are provided at the outer periphery of the pillar portion.

  As shown in FIG. 6, in the dismantling method of the second embodiment, first, a section 39 in the major axis direction is set in a section 40 in the major axis direction where the concrete structure 37 is to be segmented. In the present embodiment, one dividing surface 39 is set so as to intersect with the web of the H-shaped steel 45.

Next, drilling is performed from the upper surface of the concrete structure 37 using a hammer drill or the like, and a plurality of holes 41 in the major axis direction are formed in the dividing surface 39 as shown in FIGS. As shown in FIG. 7, the hole 41 a on both outer sides of the hole 41 is formed in the vicinity of the inner side of the reinforcing bar (the strip 47 or the like) of the outer peripheral portion of the column part of the concrete structure 37.
The drilling depth and diameter of the hole 41 can be set in the same manner as in the first embodiment. In addition, about the space | interval of the hole part 41, except for the space | interval of the hole parts 41 arrange | positioned on both sides of the web of H-shaped steel 45, it determines according to the intensity | strength etc. of the concrete 39 like 1st Embodiment, What is necessary is just to set with about 150 mm-500 mm. The hole 41 arranged adjacent to the web of the H-shaped steel 45 may have a distance from the web so that the crack reaches the web at the time of blasting.

  After forming the holes 41 in this way, the linear explosives 19 and the inclusions 25 are installed in the respective holes 41 as in the first embodiment, and the linear explosives 19 are blasted.

  FIG. 8 shows a perspective view of the concrete structure 37 after blasting. As shown in FIG. 8, after blasting, in the concrete structure 37, a through crack 51 is formed at the position of the dividing surface 39 (see FIG. 6), and the concrete 38 is divided and roughly divided. Further, at the position of the side end portion of the dividing surface 39, the cover concrete on the side surface 53 of the concrete structure 37 is crushed, and a V-shaped groove-shaped crushed portion 55 is formed.

  After the concrete structure 37 is brought into the state shown in FIG. 8 by blasting, the strip 47 exposed in the crushing portion 55 is cut with a cutter or the like. Further, the web of the H-shaped steel 45 is also cut. By cutting the band 47 and the H-shaped steel 45, it is possible to separate the member 57 of the pillar from the concrete structure 37 so as to be scraped off. The separated member 57 can be easily removed with a small heavy machine or the like.

  In the second embodiment, if necessary, in the section below the section 40, the formation of the hole, the installation and blasting of the linear explosive, the separation and removal of the divided members are repeated, and the concrete structure The unnecessary part 37 is disassembled.

Thereby, the same effects as those of the first embodiment can be obtained in the second embodiment.
Currently, in the city center, construction is often performed using the underground outer periphery of an existing building as a retaining wall for a new building. In the past, when removing unnecessary parts of the existing pillars and beam type so as not to interfere with the new building, wire saws and wall saws with low noise and vibration were used in consideration of the influence on the neighborhood. However, by separating and removing the members by the disassembling method of the present invention as shown in the second embodiment, the dismantling work can be performed with a small heavy machine or the like while suppressing noise and vibration. . Thereby, the workability of the dismantling work can be improved and the cost and the required time can be reduced.
In addition, when performing dismantling work on the ground and underground, the conventional dismantling method cannot simultaneously disassemble the ground and underground, which makes it difficult to shorten the process. However, the book as shown in the second embodiment If the dismantling method of the invention is used, even if the above-ground structure remains, a portion of the underground structure that has no safety problem can be dismantled in advance, which shortens the overall construction period. It becomes possible.

  As mentioned above, although embodiment of this invention was described referring an accompanying drawing, the technical scope of this invention is not influenced by embodiment mentioned above. It is obvious for those skilled in the art that various modifications or modifications can be conceived within the scope of the technical idea described in the claims, and these are naturally within the technical scope of the present invention. It is understood that it belongs.

DESCRIPTION OF SYMBOLS 1,37 ......... Concrete structure 2,38 ......... Concrete 3,7,39 ......... Split section 5, 5a, 5b, 9, 9a, 9b, 41, 41a, 41b ......... Hole 11, 40 ......... Section 13, 43 ......... Axial rebar 15, 47 ......... Strip 17 ......... Interval 19 ......... Linear explosives 27, 29, 51 ... …… Through cracks 31, 53 ......... Side surface 33, 35, 55 ……… Crushing part

Claims (7)

A dismantling method for dismantling a columnar concrete structure,
Forming a plurality of holes in the long axis direction in a predetermined long axis dividing section for dividing the concrete structure;
A step of arranging explosives linearly in the hole;
While blasting the explosive and dividing the concrete of the concrete structure at the dividing surface, a groove-shaped crushing portion is formed on the side surface in the major axis direction of the concrete structure at the side end of the dividing surface. Process,
A disassembling method comprising:   In the major axis cross section, the amount of explosive disposed in the hole formed near the inside of the reinforcing bar on the outer periphery of the concrete structure is made larger than the amount of explosive provided in the other hole. The disassembling method according to claim 1.   The dismantling method according to claim 1 or 2, wherein the concrete structure is divided at a plurality of the divided sections.   The disassembling method according to claim 3, wherein a plurality of the divided sections are provided so as to intersect with each other.   The distance between the adjacent side end portions is set to a size that can be grasped by a crushing device, and the member divided by the dividing section is grasped by the crushing device and crushed. The dismantling method described.   The dismantling method according to any one of claims 1 to 5, wherein the hole portions are formed at intervals of about 150 mm to 500 mm.   The dismantling method according to any one of claims 1 to 6, wherein a diameter of the hole is set to about 20 mm.

Images