JP2011157807A - Demolition method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a demolition method for dismantling a concrete structure efficiently. <P>SOLUTION: This demolition method includes a process for drilling holes in a column 1 being a concrete member from its external face and forming hole parts 11, 12 from the external face into the inside of the column 1 in a dividing part 3 for dividing the column 1, a process for arranging a linear explosive 13 in each of the hole parts 11, 12, and a process for blasting the linear explosive 13 and dividing the concrete 5 of the column 1 in the dividing part 3. When reinforcing bars such as a reinforcing bar 7 in the axial direction and a hoop 9 are arranged in the outer peripheral part of a dividing face along the dividing direction in the dividing part 3, the hole parts 11, 12 can be formed in a part 14 close to the inside of the reinforcing bars in the outer peripheral part of the dividing face and inside the dividing face in the dividing part 3. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a dismantling method. More specifically, the present invention relates to a dismantling method for dismantling a structure using an explosive.

  At present, as a method of dismantling a concrete structure such as reinforced concrete, there is a dismantling method using a large breaker or a concrete crusher. As a result, the reinforced concrete can be crushed into a glass shape relatively efficiently, and the concrete can be separated from the rebar and disassembled.

  Further, a diamond cutting method such as a disk blade (wall saw) or a wire saw is also used, and a member having a large cross section that cannot be chewed by a crusher can be cut into blocks, and scattering of concrete pieces can be suppressed. In addition, low noise and low water usage methods have been developed.

  On the other hand, a blasting method is known in which a concrete structure is crushed by perforating the structure, loading an explosive, and blasting.

  Overseas, construction methods that use the explosives such as dynamite to collapse the entire building at once are adopted, and there are several examples in Japan.

  On the other hand, there is also a method of crushing in units of members, referred to as miniblasting or controlled blasting, and examples thereof are described in Patent Documents 1 to 3. This is a construction method in which members such as columns and beams are drilled with one to several holes at locations to be crushed, charged with explosives and blasted, and the concrete is crushed and demolished at the locations.

  Furthermore, blasting with a small amount of explosive has been attempted, and the results of an experiment in which a weak detonator was embedded in the center of an unmuscle mortar specimen and attempted to cause explosions by microwave irradiation were not patented. Reported in Reference 1.

  In addition, Non-Patent Document 2 and Patent Document 4 include an example of using a shaped explosive using the Neumann effect as a method of cutting a member by arranging explosives in a linear form, and mentions application to floor slabs and the like. ing.

  As other dismantling methods, there are a method in which a reinforcing bar is electrically heated and a method in which plasma, laser, microwave, or the like is used.

Japanese Patent Laid-Open No. 2003-307038 JP 2004-293260 A JP 2005-179924 A JP 2007-16432 A Yuji Ogata, Shiro Kubota, Yuji Wada, Kiyoshi Hashizume, “Examination of Destructive Control Technology Using Micro-Explosion Sources”, Spring Meeting of the Society of Resources and Materials, 2005, p. 95-p. 96 Yuji Ogata, Shuncho Cho, Shiro Kubota, Yuji Wada, “Development of Molding Explosives for Concrete Cutting and Cutting Experiments on Mortar Specimens”, Abstracts of the 59th Annual Conference of the Japan Society of Civil Engineers, 2004, p. 617-p. 618

  However, in the dismantling method using a large breaker or a concrete crusher, noise, dust, and vibration are generated. In addition, when a large cross-section member such as a foundation beam, footing, pressure plate, etc. cannot be bitten, it is necessary to divide it with a large breaker. However, a large noise and vibration are generated, which may cause inconvenience in the vicinity. Furthermore, a space for moving heavy machinery around is required. In narrow construction or underground demolition, large heavy machinery may not be able to be put in, and the efficiency drops extremely.

  Also, diamond cutting methods such as disk blades (wall saws) and wire saws are very expensive. In addition, there is a problem that it takes time to set a cutting tool, to perform preliminary work for cutting (for example, in the case of a wire saw, core boring is required for passing a wire through a basement wall or a foundation beam) and cutting. Further, 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 the machine, and the number of uncut parts increases, so that the work efficiency decreases.

  In addition, a reinforced concrete structure is usually provided with many reinforcing bars on the outer periphery, and when crushed using a blasting method, it is subject to resistance by the reinforcing bars.

  In addition, the construction method that collapses the entire structure by a single blast requires a countermeasure against dust and debris scattering, as well as generation of loud blast sounds, vibrations, and blasts. Is possible.

  The member blasting by miniblasting (control blasting) generally requires drilling with a diameter of about 30 to 50 mm, and at the time of drilling, there is a high possibility of interfering with reinforcing bars. In addition, a hydraulic machine such as a rock drill or a crawler drill may be required, which increases the cost. There is also a problem of noise.

  In addition, during the blasting, loud explosions, vibrations, and blasts are generated, which increases the influence of nearby noise and the like. Moreover, it is a problem of cost etc. that the curing measure to be applied to the blasted portion for preventing the scattering becomes a large scale such as stacking the metallic mesh curing on the explosion-proof sheet.

  Furthermore, in this method, the number of charges per member is usually as few as one to several, and the length of the explosive charged for the member cross-sectional dimension is short, so the explosion source is practically point-like. It will be arranged, and it must be a blasting form in which the member (concrete part) is crushed conically in the direction of the minimum resistance line of the member from the explosion source.

  However, in order to divide the concrete member in the first place, it is not necessary to pulverize a part of the concrete into pieces, and it is sufficient to penetrate a crack in one section of the concrete. Therefore, in the above-described prior art, useless energy is consumed for member division, which is inefficient.

  Furthermore, at the time of blasting, a factory-produced product (processed product) in which a fixed amount of explosive is loaded in the explosive package is used as the explosive. However, since the explosive amount is fixed, Even if the amount of energy required for blasting differs depending on the charging position, the amount of explosives cannot be finely adjusted. In this respect as well, there is a problem that blasting is inefficient and wasteful explosive consumption occurs.

  Further, in an experiment using a micro explosive as shown in Non-Patent Document 1, it has been confirmed that a weak detonator is set at the center of an unmuscle mortar specimen and the mortar specimen is crushed. A method for cutting and crushing reinforced concrete members that require fracture energy has not been clarified.

  Further, in the method using a shaped explosive as shown in Non-Patent Document 2, the shaped explosive is placed on the surface of a member such as a floor slab, so the explosion source is exposed to the atmosphere, and a large explosion or blast is generated in the air. The problem is that it propagates directly inside. In addition, the steel structure can be cut by the shaped explosive, but even if the blasting is attempted by placing the shaped explosive on the surface of a concrete structure such as a floor slab, the crater-like surface layer is crushed and not cut.

  In addition, the other methods using rebar electric heating, plasma, laser, microwave, etc. have a problem that the facilities are large and inferior in practical use in the field and are uneconomical.

  The present invention has been made in view of the above-described problems, and an object thereof is to provide a dismantling method and the like for efficiently dismantling a concrete structure.

  In order to achieve the above-mentioned object, a first invention is a dismantling method for disassembling a concrete structure, wherein the concrete structure is perforated from an outer surface, and a dividing portion that divides the concrete structure is provided inside the outer surface. A step of forming a plurality of holes toward the surface, a step of arranging explosives linearly in the holes, a step of performing blasting with the explosives and dividing the concrete of the concrete structure at the dividing portion; The dismantling method characterized by comprising.

  Further, a reinforcing bar is arranged on the outer peripheral portion of the divided section along the dividing direction in the divided portion, and the hole portion is the inner portion of the outer peripheral portion of the divided section in the divided portion, and the divided section. When dividing concrete by blasting with the explosives, the concrete around the reinforcing bars on the outer periphery of the dividing section is crushed and cracks are made to penetrate the concrete inside the dividing part. Can be.

  At this time, the amount of the explosive provided in the hole near the inside of the reinforcing bar at the outer periphery of the dividing section at the dividing portion may be larger than the amount of the explosive provided in the hole inside the dividing section. it can.

  The amount of the explosive disposed in each of the holes is preferably 50 g or less.

  Furthermore, the size of the cross-section of the hole may be 20 mm or less.

  In addition, it is desirable that the explosive is disposed at a position behind the outer surface at a predetermined distance in the hole, and a inclusion is disposed at the predetermined distance from the outer surface at the hole.

  Furthermore, the hole is provided in the direction of the side of the divided section along the dividing direction at the dividing part, and the depth of the hole is 2/3 of the length of the side corresponding to the direction of the hole. Or about 200 mm shorter than the length of the side, or an intermediate length thereof.

  The explosive may be a linear explosive created by an electric detonator and a lead wire.

  In addition, in the concrete structure, a reinforcing bar is arranged on the outer side of the part from the divided part, and when the concrete is divided by blasting with the explosive, the concrete in the divided part is cracked on the inner side of the member from the reinforcing bar. You may make it penetrate.

  At this time, it is preferable that the hole is formed by drilling from an outer surface where at least a part of the reinforcing bar is exposed.

  Moreover, when forming the said hole part, it is a 1st parting part by which a reinforcing bar is arrange | positioned in the outer peripheral part of the cross section along a parting direction, and a 2nd parting part by which a reinforcing bar is arrange | positioned on the member outer side. When a plurality of parts are formed, and the concrete is divided by blasting with the explosive, the first dividing part and the second dividing part are blasted, and the concrete in the second dividing part is penetrated with a crack. It is also possible to penetrate the concrete inside the divided section of the first divided portion and push the divided concrete in the direction of the outer surface of the concrete structure.

  With the above configuration, the linear explosive can be evenly distributed and arranged at the dividing portion. At this time, for example, the depth of the hole where the explosive is arranged is about 2/3 of the length of the side corresponding to the direction of the hole, or about 200 mm shorter than the length of the side, or an intermediate length thereof. can do. In addition, when reinforcing bars are arranged on the outer periphery of the dividing section, explosives are arranged near the inside of the outer reinforcing bar and inside the dividing section, and the concrete around the reinforcing bars on the outer periphery of the dividing section is placed. While crushing, it is possible to penetrate the crack in the concrete inside the dividing portion. At this time, a larger amount of explosive than the inside can be arranged in the vicinity of the inside of the reinforcing bar at the outer peripheral portion. In a concrete structure, when a divided part is set inside the member from the reinforcing bar and the concrete is divided by blasting with an explosive, the concrete in the divided part can be penetrated through the concrete inside the member from the reinforcing bar. At this time, the hole can be formed by drilling from the outer surface where at least a part of the reinforcing bar is exposed. Furthermore, when forming the hole portion, the hole portion includes a first dividing portion in which a reinforcing bar is arranged on the outer peripheral portion of the dividing section along the dividing direction, and a second dividing portion in which the reinforcing bar is arranged outside the member. When splitting concrete by blasting with explosives, blasting is performed at the first split part and the second split part to penetrate the concrete in the second split part and the first split It is also possible to penetrate through the concrete inside the section of the section and push the divided concrete in the direction of the outer surface of the concrete structure.

In this way, by properly arranging a plurality of linear explosives at the dividing part, the energy possessed by the explosives can be used without waste for cracking and crushing of concrete. With a use amount of 50 g or less, the member can be efficiently divided. In addition, since a small amount of linear explosive is arranged in the hole, the size of the cross section of the hole can be reduced, for example, the diameter thereof can be 20 mm or less. For this reason, a large-scale machine is unnecessary, and noise, vibration, and dust are reduced. In addition, the possibility of interference with the reinforcing bar during drilling is reduced. Further, by forming the hole by drilling from the outer surface where at least a part of the reinforcing bar is exposed, the position of the reinforcing bar can be known, so that the possibility of interference with the reinforcing bar is further reduced. Thereby, the drilling cost can be reduced. In addition, since dust and flying stones are prevented from being scattered, it is only necessary to cover the blasting with an explosion-proof sheet or the like, and the workability is improved. Furthermore, the explosive to be used is a linear explosive created by an electric detonator and a detonation line, so that the explosive amount can be finely adjusted by adjusting the length of the detonation line according to the cross-sectional properties of the member such as concrete strength. Can be easily performed, and blasting is not performed with an excessive amount of explosives. Therefore, the concrete structure can be dismantled more efficiently than the conventional member blasting by miniblasting (control blasting).
In addition, it is possible to work in a narrow space compared to when a large breaker is used, noise and vibration can be reduced, and generation of noise and vibration can be suppressed instantaneously. Furthermore, compared with the case where it cut | disconnects using a wire saw and a wall saw, a required time and cost are also suppressed. In addition, after placing explosives in small-diameter holes, sealing the holes with inclusions causes blasting inside the member. Compared to the case where molded explosives are placed on the surface of the member, noise, vibration, dust, blast Can be significantly suppressed.

  According to the present invention, it is possible to provide a demolition method and the like for efficiently deconstructing a concrete structure.

The figure which shows the concrete structure demolished with the dismantling method of 1st Embodiment The figure which shows the dismantling method of 1st Embodiment. The figure which shows the dismantling method of 1st Embodiment. Illustration showing examples of linear explosives The figure which shows the dismantling method of 1st Embodiment. The figure which shows the concrete structure demolished with the dismantling method of 2nd Embodiment The figure which shows the dismantling method of 2nd Embodiment. The figure which shows the dismantling method of 2nd Embodiment. The figure which shows the concrete structure demolished with the dismantling method of 3rd Embodiment The figure which shows the dismantling method of 3rd Embodiment. The figure which shows the dismantling method of 3rd Embodiment. The figure which shows the dismantling method of 3rd Embodiment. The figure which shows the concrete structure demolished with the demolishing method of 4th Embodiment The figure which shows the dismantling method of 4th Embodiment. The figure which shows the dismantling method of 4th Embodiment. The figure which shows the dismantling method of 4th Embodiment. The figure which shows the dismantling method of 4th Embodiment. The figure which shows the dismantling method of 4th Embodiment. The figure which shows the dismantling method of 4th Embodiment. The figure which shows the dismantling method of 4th Embodiment.

  Embodiments of the disassembly method of the present invention will be described below with reference to the drawings.

  First, a first embodiment of the dismantling method of the present invention will be described with reference to FIGS. The dismantling method of the first embodiment will be described by taking as an example the case of dismantling a reinforced concrete structure column as shown in FIG. 1 as a concrete structure.

  That is, in the dismantling method of the present embodiment, a desired minimum amount of explosives is obtained by loading a plurality of explosives in a line at an arbitrary part 3 of the pillar 1 shown in FIG. Then, a crack is made to penetrate the concrete part inside the member, and the concrete around the reinforcing bars in the outer peripheral part is crushed and divided in the horizontal direction.

  FIG.1 (b) is sectional drawing which looked at the divided part 3 along a dividing direction (horizontal direction) in the direction of arrow A of Fig.1 (a) in the dividing part 3 which loads an explosive. The column 1 is provided so as to surround the concrete 5, the axial rebar 7 provided in the column axis direction, and the axial rebar 7 in a horizontal section (divided section of the dividing portion 3) perpendicular to the column axis direction. It is assumed to be constituted by the muscle 9.

  In the disassembling method of the present embodiment, first, the column 1 is mounted using a hammer drill or the like so that the dividing section 3 is shown in FIG. 2A and the inside of the dividing portion 3 is shown in FIG. The dividing part 3 is perforated from the outer surface of the pillar 1, and the hole part 11 and the hole part 12 are formed in the dividing part 3 from the outer surface of the pillar 1 to the inside of the pillar 1. The hole 11 and the hole 12 are provided so as not to interfere with the axial rebar 7 and the band 9.

  The hole part 11 and the hole part 12 are each provided in the direction of two orthogonal sides of the dividing surface of the dividing part 3. The hole 11 is provided in the vertical direction of the sectional surface shown by the vertical direction in FIG. The hole 12 is provided in the lateral direction of the sectional surface shown in the lateral direction in FIG.

  As shown in FIG. 2, a plurality of hole portions 11 are provided at appropriate intervals along the lateral direction of the divided section according to the length in the lateral direction of the divided section. The interval can be, for example, about 150 mm to 200 mm.

  The holes 11 at both ends in the horizontal direction are provided in the vertical direction in the vicinity of the inside of the reinforcing bars (axial reinforcing bars 7 and strips 9) provided on the outer peripheral portion of the dividing surface. The holes 11 provided in the meantime are provided in the longitudinal direction at appropriate intervals inside the dividing plane.

  The holes 12 are provided at both ends in the vertical direction of the dividing surface, and are provided in the lateral direction in the vicinity of the inside of the reinforcing bars (axial reinforcing bars 7 and 9) of the outer periphery of the dividing surface. In addition, the hole 12 is provided by shifting the position in the column axis direction so as not to interfere with the hole 11, and a clearance is taken.

  As will be described later, since a small amount of explosive is arranged linearly in each hole, the cross section can be reduced in diameter. In the present embodiment, the diameters of the cross sections of the hole 11 and the hole 12 can be 20 mm or less. Moreover, the depth of the hole 11 and the hole 12 is about 2/3 of the length of the side corresponding to the direction of the hole 11 and the hole 12 or about 200 mm shorter than the length of the side. Or an intermediate length between them.

  Next, the amount of explosive energy required is calculated by calculating the required amount of blasting energy according to the concrete strength, cross-sectional properties such as the amount of reinforcing bars and steel frames, the drilling position, etc., and FIG. As shown in FIG. 3B, the linear explosive 13 is set in the hole 11 and the hole 12 so as to show the inside of the dividing part 3. The linear explosive 13 is set at a position farther from a position away from the outer surface of the pillar 1 by a predetermined distance, for example, about 200 mm, at each hole.

  As shown in FIG. 4, the linear explosive 13 is created by the electric detonator 15 and the explosive wire 17 by fixing the electric detonator 15 connected to the leg wire to the explosive wire 17 with a tape or the like. The amount of explosive can be freely adjusted by adjusting the length of the explosive wire 17. Explosives can be pre-manufactured at an explosives factory, etc., or they can be easily created at an on-site pyrotechnics while checking the blasting results at the site, so the amount of explosives can be easily controlled and placed in each hole. The amount of explosive to be performed can be minimized. When the member has a small cross section, only the electric detonator 15 may be provided.

  In the present embodiment, the explosives in the inner vicinity portion 14 of the reinforcing bars (axial reinforcing bars 7, strips 9) in the outer peripheral portion of the divided section at the hole portions 11 and 12 are larger than those inside the other divided sections. Load the amount. For example, about twice the amount of explosive is loaded. Further, the amount of explosive loaded in the hole 11 and the hole 12 can be set to a minute amount of 50 g or less, preferably 30 g or less, respectively.

  Further, in the hole 11 and the hole 12, the inclusion 19 such as sand is packed at a predetermined distance from the outer surface of the pillar 1, for example, about 200 mm from the outer surface, and the hole 11 and hole 12 on the outer surface of the pillar 1 are packed. Tamping is performed at the opening. For connection, the leg of the electric detonator 15 is left outside each hole.

  Thereafter, the electric detonator 15 is connected to the blasting device through a bus or the like, covered with the explosion-proof sheet or the like, cured, and blasted. An example of a state in the vicinity of the dividing portion 3 of the pillar 1 after blasting is shown in a perspective view in FIG. 5 (a) and in a side view in FIG. 5 (b).

  The tensile stress acts continuously on the concrete 5 by the reflected tensile wave of the shock wave generated at the time of blasting and the expansion force of the post gas, so that the energy generated by the blasting acts intensively in the dividing portion 3 without being dispersed. The crack 21 can penetrate the concrete 5 with a minimum amount of explosive.

  In addition, in the vicinity of the inside of the reinforcing bars (axial reinforcing bars 7 and straps 9) arranged on the outer periphery of the split section, a relatively large amount of explosive than the inside of the split section is linearly charged and blasted. Therefore, the compressive stress wave propagates and acts from the linear explosion source in the direction of the minimum resistance line (reinforcing concrete cover direction) due to the shock wave and gas pressure at the time of blasting, and from the explosion source to the free surface (outer surface of the column 1) Part of the concrete 5, that is, the concrete 5 around the outer periphery of the reinforcing bar is crushed and removed, and the outer peripheral part of the reinforcing bar is exposed. Thereby, the space for cut | disconnecting the reinforcement of an outer peripheral part is formed, and the cutting operation of a reinforcement becomes possible.

  As a result, it is possible to create a state in which the members of the column 1 are connected only through the reinforcing bars (axial reinforcing bars 7) on the outer peripheral portion while the concrete 5 is completely divided at the dividing portion 3.

  Next, the reinforcing bars (axial reinforcing bars 7) that connect the members remaining after blasting are cut by gas fusing or the like, and the members of the pillar 1 are cut. At this time, if there is a piece of concrete around the reinforcing bar that interferes with the cutting of the reinforcing bar, remove it with a hammer. However, if an appropriate amount of explosives is set, concrete crushing can be minimized, so this work is almost unnecessary.

  Thereafter, as shown in FIG. 5C, the divided members are removed by a crane, a hydraulic excavator or the like. In addition, in the state shown to Fig.5 (a) and FIG.5 (b), the concrete 5 can also be chewed with a normal crusher.

  As described above, according to the disassembling method of the present embodiment, the cut surface by blasting is formed so as to divide the member.

  Therefore, it is possible to work in a small space compared to when a large breaker is used, noise and vibration can be reduced, and generation of noise and vibration can be suppressed instantly.

  Moreover, compared with the case where it cut | disconnects using a wire saw or a wall saw, it can aim at a cost reduction and shortening of a construction period. Based on the experimental results of blasting and dismantling, the cost of cutting an RC beam with a cross section of 1.0m x 1.0m by two workers was calculated. When cutting using a wire saw or wall saw, In comparison, it was possible to reduce the time required for cutting the cross section by about 50% and the material cost by about 70%.

  Further, in the dismantling method of the present embodiment, since a small amount of explosive is linearly arranged in each of the plurality of holes, the diameter of the perforation can be reduced as compared with conventional miniblasting (control blasting). For example, the size of the cross section of the hole can be set to 20 mm or less in diameter. For this reason, a large-scale machine is not required, and noise, vibration, and dust are reduced. In addition, the possibility of interference with the reinforcing bar during drilling is small, and even if it interferes, the diameter is small and it is easy to escape. This reduces the drilling cost.

  When blasting, a plurality of linear explosives can be appropriately arranged, and the target member can be most efficiently broken by using the minimum amount of explosive. In other words, the minimum amount of explosives can be distributed almost evenly in the section of the dividing part, so that the blasting energy can be used efficiently for cracking and crushing of concrete, minimizing the amount of explosives used. For example, the amount used can be 50 g or less, preferably 30 g or less in each hole. This not only has the effect of suppressing noise, vibration, dust and the like, and also suppressing the scattering of stepping stones, but also provides an effect that the blasting section need only be covered with an explosion-proof sheet or the like. Including these, it is possible to improve workability and reduce costs throughout the dismantling process.

  In addition, the explosive used is different from the factory-produced product (processed product) where the amount of explosive is constant, just by adjusting the length of the explosive wire according to the cross-sectional properties of the member, such as concrete strength and the amount of reinforcing bars. Explosives usage can be fine-tuned freely, so there is no blasting with excessive amounts of explosives than necessary.

  Further, in the dismantling method of the present embodiment, the explosive wire is charged in the small-diameter hole, and then the hole is sealed with inclusions such as sand, so that blasting occurs inside the member, and the molded explosive and the like are applied to the surface of the member. Compared with the installation, generation of noise, vibration, dust, blast, etc. can be greatly suppressed.

  As described above, according to the dismantling method of the present embodiment, the concrete structure can be dismantled efficiently.

  Subsequently, a second embodiment of the disassembling method of the present invention will be described with reference to FIGS. The dismantling method of the second embodiment will be described by taking as an example the case of dismantling a reinforced concrete structure beam as shown in FIG. 6 as a concrete structure.

  That is, in the disassembling method of this embodiment, at an arbitrary dividing portion 31 of the beam 30 shown in FIG. 6 (a) where it is desired to cut the member, a plurality of explosives are loaded in a line shape to perform blasting, and the minimum amount of explosive is required. Then, a crack is made to penetrate through the concrete part inside the member, and the concrete around the reinforcing bars in the outer peripheral part is crushed and divided in the vertical direction.

  FIG. 6B is a cross-sectional view of the dividing section 31 in which the explosive is loaded, as seen in the direction of the arrow B in FIG. The beam 30 is provided so as to surround the concrete 32, the axial rebar 33 provided in the beam axis direction, and the axial rebar 33 in a vertical section (divided section of the dividing portion 31) perpendicular to the beam axis direction. Suppose that it is comprised with the line | wire 35. FIG.

  Also in the disassembling method of the second embodiment, first, using a hammer drill or the like, as shown in FIG. 7 (a), the dividing section 31 and in FIG. 7 (b), the inside of the dividing section 31, respectively. The beam 30 is perforated from the outer surface of the beam 30 by the dividing portion 31, and a hole portion 37 and a hole portion 39 extending from the outer surface of the beam 30 to the inside of the beam 30 are formed in the dividing portion 31. The hole 37 and the hole 39 are provided so as not to interfere with the axial rebar 33 and the band 35.

  The hole part 37 and the hole part 39 are each provided in the direction of two sides perpendicular to each other in the dividing section of the dividing part 31. As shown in FIG. 7, the hole part 37 is provided toward the height direction (vertical direction in FIG. 7A) of the dividing surface. The hole 39 is provided in the depth direction of the dividing surface (in the lateral direction in FIG. 7A).

  As shown in FIG. 7, a plurality of hole portions 37 are provided at appropriate intervals along the depth direction of the divided section in accordance with the depth length of the divided section. The interval can be, for example, about 150 mm to 200 mm.

  The holes 37 at both ends in the depth direction are provided in the height direction in the vicinity of the inner side of the reinforcing bars (axial reinforcing bars 33 and strips 35) provided on the outer peripheral portion of the dividing surface. The holes 37 provided between them are provided in the height direction at appropriate intervals inside the dividing plane.

  The holes 39 are provided at both ends in the height direction of the divided section, and are provided in the depth direction in the vicinity of the inner side of the reinforcing bars (axial reinforcing bars 33 and band bars 35) of the outer periphery of the divided section. The hole 39 is provided with a position shifted in the beam axis direction so as not to interfere with the hole 37, and a clearance is provided.

  Similar to the first embodiment, the size of the cross section of the hole 37 and the hole 39 can be as small as 20 mm or less in diameter. In addition, the depth of the hole 37 and the hole 39 is about 2/3 of the length of the side corresponding to the direction of the hole 37 and the hole 39 or about 200 mm shorter than the length of the side. Or an intermediate length between them.

  Further, depending on the concrete strength, cross-sectional properties such as the amount of reinforcing bars and steel frames, and the drilling position, the amount of explosive energy required is calculated to obtain an appropriate amount of explosive, and the linear explosive 41 is placed in the hole 37 and hole 39. set. The linear explosive 41 is set at a position farther from a position away from the outer surface of the beam 30 by a predetermined distance, for example, about 200 mm, at each hole.

  As in the case of the first embodiment, the linear explosive 41 can be made of an electric detonator and an explosive wire as shown in FIG. The amount of explosive can be adjusted freely by adjusting the length of the lead wire. Explosives can be manufactured in advance at an explosives factory, etc., and can be easily created at a pyrotechnic site in the site while checking the blasting results at the site. The amount of explosives can be easily controlled and placed in each hole. The amount of explosive to be performed can be minimized. When the member has a small cross section, only the electric detonator 15 may be provided.

  Also in the present embodiment, the explosives in the inner vicinity portion 45 of the reinforcing bars (axial reinforcing bars 33, straps 35) in the outer periphery of the dividing surface at the hole 37 and the hole 39 are larger than the other inside of the dividing surface. Load the amount. For example, about twice the amount of explosive is loaded. Further, the amount of explosive loaded in the hole 37 and the hole 39 can be set to a minute amount of 50 g or less, preferably 30 g or less, respectively.

  Similarly to the first embodiment, the hole 37 and the hole 39 are filled with inclusions 43 such as sand at a predetermined distance from the outer surface of the beam 30, for example, about 200 mm from the outer surface, and the outer surface of the beam 30. Tamping is performed at the openings of the holes 37 and 39. Similar to the first embodiment, the leg of the electric detonator goes out of each hole.

  Then, the leg of the electric detonator is connected to the blasting device through a bus or the like, covered with the explosion-proof sheet, etc., cured, and blasted. FIG. 8A is a perspective view and FIG. 8B is a side view showing an example of a state in the vicinity of the split portion 31 of the beam 30 after blasting.

  Also in this embodiment, the tensile stress is continuously applied to the concrete 32 by the reflected tensile wave of the shock wave generated at the time of blasting and the expansion force of the post gas, so that the energy generated by the blasting is not dispersed in the dividing portion 31. It acts intensively and allows cracks 47 to penetrate concrete 32 with a minimal amount of explosive.

  In addition, in the vicinity of the inside of the reinforcing bars (axial reinforcing bars 33, straps 35) arranged on the outer periphery of the dividing plane, a relatively large amount of explosive is charged and blasted in a linear manner. As a result, the compressive stress wave propagates and acts from the linear explosion source in the direction of the minimum resistance line (reinforced concrete covering direction) due to the shock wave and gas pressure at the time of blasting, and from the explosion source to the free surface (outer surface of the beam 30) A portion of the concrete 32, that is, the concrete 32 around the outer periphery of the reinforcing bar is crushed and removed, and the outer peripheral portion of the reinforcing bar is exposed. Thereby, the space for cut | disconnecting the reinforcement of an outer peripheral part is formed, and the cutting operation of a reinforcement becomes possible.

  As a result, it is possible to create a state in which the members of the beam 30 are connected only through the reinforcing bars (axial reinforcing bars 33) on the outer peripheral portion while the concrete 32 is completely divided at the dividing portion 31.

  Next, the reinforcing bars (axial reinforcing bars 33) connecting the members remaining after the blasting are cut by gas cutting or the like, and the members of the beam 30 are cut. At this time, if there is a piece of concrete around the reinforcing bar that interferes with the cutting of the reinforcing bar, remove it with a hammer. As in the first embodiment, if an appropriate amount of explosive is set, the crushing of the concrete can be kept to a minimum, and this work is almost unnecessary.

  Thereafter, as shown in FIG. 8C, the divided members are removed by a crane, a hydraulic excavator or the like. In addition, in the state shown to Fig.8 (a) and FIG.8 (b), the concrete 32 can also be chewed with a normal crusher.

  As described above, even in the dismantling method according to the present embodiment, a plurality of linear explosives are appropriately loaded in the dividing portion 31 for blasting, and the concrete portion inside the concrete structure member is cracked with the minimum amount of explosive. The concrete around the reinforcing bars on the outer periphery can be crushed. Thereby, the effect similar to the above-mentioned embodiment is acquired, and a concrete structure can be demolished efficiently.

  Next, a third embodiment of the present invention will be described with reference to FIGS. The dismantling method of the third embodiment will be described by taking as an example the case of dismantling a large-section member 50 of a reinforced concrete structure as shown in FIG. 9 as a concrete structure.

  That is, in the disassembling method of the present embodiment, the explosive in the vertical dividing portion 53 and the horizontal dividing portion 55 which are arbitrary dividing portions to be cut of the member 50 having a large cross section shown in FIG. Blasting with a plurality of lines, pierce the concrete part inside the member with the minimum amount of explosive, crush the concrete around the reinforcing bar on the outer periphery, and make the member vertically and horizontally respectively Divide. In the present embodiment, the member 50 is divided by blasting at the dividing portion 53 and the dividing portion 55, and the upper left member 51 of the member 50 is cut out and disassembled.

  FIG. 9B is a cross-sectional view of the dividing section 53 in which the explosive is loaded, along a dividing section along the dividing direction (vertical direction) as seen in the direction of arrow C in FIG. FIG. 9C is a cross-sectional view of the dividing section 55 in which the explosive is loaded, as seen in the direction of the arrow D in FIG. The member 50 is composed of concrete 56, a horizontal reinforcing bar 57 provided in the horizontal direction, and a band reinforcing bar 59 provided so as to surround the horizontal reinforcing bar 57 in a cross section in the vertical (height) direction.

  In addition, the dividing part 53 and the dividing part 55 share an end (the lower end part of the dividing part 53 and the right end part of the dividing part 55 in FIG. 9A), and the dividing part 55 is a horizontal reinforcing bar in the height direction. 57.

  Also in the disassembly method of the third embodiment, a member 50 is used by using a hammer drill or the like as shown in FIG. 10 (a) showing a divided section of the divided portion 53 and FIG. 10 (b) showing the inside of the divided portion 53. Are cut from the outer surface of the member 50 by the dividing portion 53, and a hole portion 61 and a hole portion 63 that extend from the outer surface of the member 50 to the inside of the member 50 are formed in the dividing portion 53. Further, as shown in FIG. 11 (a) and a sectional view of the dividing portion 55, and FIG. 11 (b), the inside of the dividing portion 55, the hole extending from the outer surface of the member 50 to the inside of the member 50 is also provided in the dividing portion 55. A portion 65 and a hole 67 are formed. The hole 61, the hole 63, the hole 65, and the hole 67 are provided so as not to interfere with the horizontal rebar 57 and the band 59.

  The hole 61 and the hole 63 are provided in the direction of two sides orthogonal to each other in the dividing section of the dividing portion 53. As shown in FIG. 10, the hole 61 is provided in the height direction of the dividing surface (vertical direction in FIG. 10A). The hole 63 is provided in the depth direction (lateral direction in FIG. 10A) of the dividing surface.

  As shown in FIG. 10, a plurality of hole portions 61 are provided at appropriate intervals along the depth direction of the divided section in accordance with the depth length of the divided section. The interval can be, for example, about 150 mm to 200 mm.

  The holes 61 at both ends in the depth direction are provided in the height direction in the vicinity of the inside of the reinforcing bars (horizontal reinforcing bars 57 and band reinforcing bars 59) provided on the outer peripheral portion of the dividing surface. The holes 61 provided therebetween are provided in the height direction at appropriate intervals inside the dividing plane.

  The hole 63 is provided at the upper end portion in the height direction of the divided section, and is provided in the depth direction in the vicinity of the inner side of the reinforcing bars (horizontal reinforcing bars 57 and 59) of the outer periphery of the divided section. In addition, the hole 63 is provided by shifting the position in the width direction of the member 50 (the horizontal direction in FIG. 9A) so as not to interfere with the hole 61, and a clearance is taken.

  The hole portion 65 and the hole portion 67 are provided in the directions of two sides perpendicular to each other in the divided section of the dividing portion 55. As shown in FIG. 11, the hole 65 is provided toward the depth direction of the dividing surface (vertical direction in FIG. 11A). The hole 67 is provided in the lateral width direction (lateral direction in FIG. 11A) of the sectional surface.

  As shown in FIG. 11, a plurality of hole portions 65 are provided in the inside of the divided section at appropriate intervals along the width direction of the divided section according to the width of the divided section and the like. The interval can be, for example, about 150 mm to 200 mm.

  The holes 67 are provided at both ends in the depth direction of the dividing surface, and are provided in the lateral width direction in the vicinity of the inside of the reinforcing bar (strand 59) of the outer periphery of the dividing surface. The hole 67 is provided with a position shifted in the height direction so as not to interfere with the hole 65, and a clearance is taken.

  As in the first and second embodiments, in this embodiment, the size of the cross section of the hole 61, the hole 63, the hole 65, and the hole 67 is such that the diameter is as small as 20 mm or less. Can do. Further, the depth of the hole 61 and the hole 63 is about 2/3 of the length of the side corresponding to the direction of the hole 61 and the hole 63 in the divided section of the dividing portion 53, or the length of the side. The length may be as short as about 200 mm or an intermediate length. Similarly, the depth of the hole portion 65 and the hole portion 67 is about 2/3 of the length of the side corresponding to the direction of the hole portion 65 and the hole portion 67 in the divided section of the dividing portion 55, or The length may be about 200 mm shorter than the length or an intermediate length thereof.

  Furthermore, the amount of explosive energy required is calculated according to the concrete strength, cross-sectional properties such as the amount of reinforcing bars and steel frames, and the drilling position to obtain an appropriate amount of explosive, and as shown in FIGS. 10 and 11, linear explosives are obtained. 69 is set in the hole 61, the hole 63, the hole 65, and the hole 67. The linear explosive 69 is set at a position farther from a position away from the outer surface of the member 50 by a predetermined distance, for example, about 200 mm, at each hole.

  As in the first and second embodiments, the linear explosive 69 can be made of an electric detonator and an explosive wire as shown in FIG. The amount of explosive can be adjusted freely by adjusting the length of the lead wire. Explosives can be manufactured in advance at an explosives factory, etc., and can be easily created at a pyrotechnic site in the site while checking the blasting results at the site. The amount of explosives can be easily controlled and placed in each hole. The amount of explosive to be performed can be minimized.

  Also in the present embodiment, in the dividing portion 53, the hole 61 and the hole 63 are the inner peripheral portion 73 of the outer peripheral portion of the dividing section (the axial reinforcing bar 57 and the band reinforcing bar 59), and the other divided sections. Load more explosives than inside. For example, about twice as much explosive amount is loaded. Similarly, in the dividing portion 55 (in the hole portion 67), the inner portion 75 in the vicinity of the inner side of the reinforcing bar (strand 59) in the outer peripheral portion of the divided section, than in the other portion (in the hole portion 65). Load a large amount of explosives. For example, about twice as much explosive amount is loaded. The amount of explosive loaded in the hole 61, the hole 63, the hole 65, and the hole 67 can be set to a minute amount of 50 g or less, preferably 30 g or less, respectively.

  Similarly to the first and second embodiments, the hole 61, the hole 63, the hole 65, and the hole 67 have a predetermined distance from the outer surface of the member 50, for example, about 200 mm from the outer surface, sand or the like. The stuffing 71 is packed and tamping is performed at the openings of the hole 61, the hole 63, the hole 65, and the hole 67 on the outer surface of the member 50. As in the first and second embodiments, the leg of the electric detonator goes out of each hole.

  Then, the leg of the electric detonator is connected to the blasting device through a bus or the like, covered with the explosion-proof sheet, etc., cured, and blasted. An example of a state in the vicinity of the divided portion 53 and the divided portion 55 of the member 50 after blasting is shown in FIG.

  Also in this embodiment, the tensile stress is continuously applied to the concrete 56 by the reflected tensile wave of the shock wave generated at the time of blasting and the expansion force of the post gas, so that the energy generated by the blasting is not dispersed, and the split part 53, the split It acts intensively in the portion 55, and can penetrate the concrete 56 with the minimum amount of explosive, the crack 73 in the divided portion 53, and the crack 75 in the divided portion 55, respectively.

  Further, in each of the dividing section 53 and the dividing section 55, the amount relatively larger than the inside in the vicinity of the inner side of the reinforcing bars arranged in the outer peripheral portion (the horizontal reinforcing bars 57 and the reinforcing bars 59). By charging and exploding the explosive in a linear fashion, a compressive stress wave propagates and acts from the linear explosive source in the direction of the minimum resistance line (reinforced concrete cover direction) due to the shock wave and gas pressure at the time of blasting. To the free surface (the outer surface of the member 50), that is, the concrete 56 around the reinforcing bars in the outer peripheral portion is crushed and removed, and the reinforcing bars in the outer peripheral portion are exposed. Thereby, the space for cut | disconnecting the reinforcement of an outer peripheral part is formed, and the cutting operation of a reinforcement becomes possible.

  Thereby, while the concrete 56 is completely divided at the divided portion 53 and the divided portion 55, a state in which the member 50 is connected only through the reinforcing bars (horizontal reinforcing bars 57 and strips 59) on the outer peripheral portion can be created. it can.

  After blasting in this manner, the remaining reinforcing bars such as the horizontal reinforcing bar 57 and the reinforcing bar 59 are cut by gas fusing or the like, and the member 51 is cut off from the member 50. At this time, if there is a piece of concrete around the reinforcing bar that interferes with the cutting of the reinforcing bar, remove it with a hammer. Similar to the first and second embodiments, if an appropriate amount of explosive is set, the crushing of the concrete can be kept to a minimum, and this work is almost unnecessary.

  Thereafter, as shown in FIG. 12B, the divided member 51 is removed by a crane, a hydraulic excavator, or the like. In addition, in the state shown to Fig.12 (a), concrete can also be crushed with a normal crusher.

  As described above, even in the dismantling method of the present embodiment, a plurality of linear explosives are appropriately loaded in the dividing portion 53 and the dividing portion 55 to perform blasting, and the inside of the member of the concrete structure with the necessary minimum amount of explosives. It is possible to break through the cracks in the concrete part of the concrete and crush the concrete around the reinforcing bars on the outer peripheral part. Thereby, the effect similar to the above-mentioned embodiment is acquired, and a concrete structure can be demolished efficiently.

Next, a fourth embodiment of the present invention will be described with reference to FIGS.
The dismantling method of the fourth embodiment will be described by taking as an example a case where a foundation beam 80 having a reinforced concrete structure as shown in FIG. 13 is dismantled as a concrete structure.

  13A is a view of the foundation beam 80 as viewed from above, and FIG. 13B is a cross-sectional view of the foundation beam 80 taken along line A-A ′. The foundation beam 80 includes a concrete 83, an axial reinforcing bar 84 provided in the beam axial direction, and a band reinforcing bar 85 provided so as to surround the axial reinforcing bar 84 in a vertical cross section perpendicular to the beam axial direction.

  In the disassembly method of this embodiment, the foundation beam 80 is disassembled in several times. That is, the foundation beam 80 is disassembled by being divided into members 80a, 80b, 80c, 80d, and 80e shown in FIG. At this time, disassembly is performed in order from the center to the end of the foundation beam 80 along the beam axis direction.

  In the disassembling method of this embodiment, first, as in the second embodiment, the explosive is linearly loaded at the dividing portion 81a, blasting is performed, the foundation beam 80 is divided in the vertical direction, and the member 80a is removed. At this time, the dividing portion 81a is set obliquely with respect to the plane axial direction of the beam, the dividing section is a tapered surface, and the plane of the member 80a after blasting is a trapezoid. Then, the rebar remaining after blasting is cut, and the divided member 80a is taken out to the bottom side of the trapezoid and removed. The foundation beam 80 after removing the member 80a is shown in FIG.

  Next, blasting is performed at the dividing portion 81b, the foundation beam 80 is divided in the vertical direction, and the member 80b is removed. FIG. 14B is a cross-sectional view of the foundation beam 80 taken along line B-B ′ in FIG. In the present embodiment, as in the second embodiment, explosives are linearly loaded at the dividing portion 81b for blasting, and inside the reinforcing bars outside the members of the foundation beam 80 (the axial reinforcing bars 84 and the band reinforcing bars 85). Then, the dividing part 82b is set in the beam axis direction, and the dividing part 82b is also loaded with explosives in a linear shape to blast, thereby dividing the concrete 83.

  FIG. 15 is a perspective view showing the inside of the member 80b loaded with explosives. The dividing part 81b hits the left end part in FIG. As shown in FIG. 15, the dividing portion 81b is provided with a hole as in the second embodiment. In other words, the holes 87 and 89 are provided in the vicinity of the inner side of the reinforcing bars (axial reinforcing bars 84 and strips 85) on the outer periphery of the divided section of the foundation beam 80 and in the divided section.

  Furthermore, in this embodiment, a linear explosive is further arrange | positioned also in the above-mentioned parting part 82b, and the concrete 83 is parted. FIG. 16 is a view showing a dividing portion 82b of a member 80b in which explosives are loaded in the holes 91 and 93. FIG. 16 (a) is a sectional view taken along line BB ′ in FIG. 14 (a), and FIG. ) Is a view of the dividing portion 82b of the member 80b as viewed from above, and FIG. 16C is a view of the dividing portion 82b of the member 80b as viewed from the side.

  That is, the foundation beam 80 is drilled from the outer surface using a hammer drill or the like, and the holes 91 and 93 from the outer surface to the inside of the foundation beam 80 are formed as reinforcing bars (axial reinforcing bars) in the outer peripheral portion of the cross section in the vertical direction of the foundation beam 80. 84, inside the member from the band 85), the directions of two sides perpendicular to the cross section (the height direction of the cross section (the vertical direction in FIG. 16A) and the depth direction (the horizontal direction in FIG. 16A)) Provide toward. The hole portion 91 in the height direction and the hole portion 93 in the depth direction are provided so as to be displaced in the beam axis direction so as not to interfere with each other, and clearance is taken. Further, the size of the holes 91 and 93 is set to be as small as 20 mm or less as in the first to third embodiments, and the depth of the holes 91 and 93 is set in the direction of each hole. The length of the side of the corresponding member 80b can be about 2/3, or about 200 mm shorter than the length of the side, or the middle thereof. The interval at which the holes 91 and 93 are provided in the beam axis direction can be determined as appropriate according to the density of the axial reinforcing bars 84 and the band bars 85.

  15 and 16 are examples in which a hole is formed by drilling from the side surface of the foundation beam 80. As shown in FIGS. 17 and 18, the member 80a is removed, and at least a part of the reinforcing bar is formed. The exposed reinforcing bars (axial reinforcing bars 84 and 85) of the outer peripheral portion of the cross section in the vertical direction of the member 80b are drilled in the beam axis direction from the free surface 100 (outer surface) of the member 80b orthogonal to the beam axis direction. Further, a hole 99 can be provided on the inner side of the member toward the beam axis direction of the member 80b. FIG. 17 is a perspective view showing the inside of the member 80 b in which the explosive is loaded in the hole 99. 18A and 18B are diagrams showing the dividing portion 82b of the member 80b in which the explosive is loaded in the hole 99. FIG. 18A is a cross-sectional view taken along the line BB 'in FIG. 14A, and FIG. The figure which looked at the parting part 82b of the member 80b from the upper surface, FIG.18 (c) is the figure which looked at the parting part 82b of the member 80b from the side.

  The size of the hole 99 is the same as the holes 91 and 93 so that the diameter is as small as 20 mm or less, and the depth of the hole 99 corresponds to the direction of the hole 99 as with the holes 91 and 93. The length of the side of the member 80b to be about 2/3, or about 200 mm shorter than the length of the side, or the middle thereof. The hole 99 extends in the direction of two sides perpendicular to the vertical cross section of the foundation beam 80 (the height direction of the cross section (the vertical direction in FIG. 18A) and the depth direction (the horizontal direction in FIG. 18A)). The interval to be provided can also be determined as appropriate according to the density of the axial reinforcing bars 84 and the reinforcing bars 85. When drilling in the beam axis direction from the free surface, the position of the reinforcing bar on the outer periphery in the cross section is known, so that the drilling position can be easily determined.

  Then, as in the first to third embodiments, the amount of explosive energy required is calculated according to the cross-sectional properties such as the strength of the concrete, the amount of reinforcing bars and steel frames, and the drilling position, and an appropriate explosive amount is obtained. The linear explosive 95 created by the explosive wire is set in the holes 91 and 93 or the hole 99 including the holes 87 and 89 of the dividing portion 81b. The linear explosive 95 is set at a position that is a predetermined distance away from the outer surface of the foundation beam 80 at each hole, for example, about 200 mm away, and is inserted into a position at a predetermined depth from the outer surface at each hole. An object 97 is arranged. The amount of explosive charged in the holes 87 and 89 and the holes 91 and 93 or the hole 99 can be 50 g or less, preferably 30 g or less.

  Explosives are arranged as described above, and the dividing portion 82b and the dividing portion 81b are blasted in the same manner as in the first to third embodiments. Then, as shown in FIG. 19, the concrete or the like outside the member is pushed out of the member from the dividing portion 82 b, the crack 101 penetrates the concrete 83 in the dividing portion 82 b of the foundation beam 80, and also in the dividing portion 81 b, As with the second embodiment, cracks occur in the concrete 83 inside the dividing surface by blasting. As a result, the internal concrete 103 is divided into a substantially U shape in the cross section in the beam axis direction. Furthermore, the concrete 103 is pushed out in the direction of the free surface (outer surface) formed by removing the member 80a by blasting the dividing portion 81b.

  After that, the reinforcing bars remaining on the outer side of the dividing portion 82b and the remaining portions of the dividing portion 81b are cut, the reinforcing bars and concrete on the outer peripheral portion of the cross section in the vertical direction of the foundation beam 80 are removed, and the inner concrete 103 is removed. 80b is removed.

  Thereafter, the member 80d is similarly removed. On the opposite side of the members 80b and 80d along the beam axis direction, blasting is performed in the same manner as the members 80c and 80e in order toward the end portion, and removal and disassembly are performed. In this way, the foundation beam 80 is disassembled as shown in FIG.

  Further, the blasting and dismantling of the foundation beam 80 after removing the member 80a can be performed for a plurality of members at once. That is, the explosive is arranged linearly in the divided portions 81b to 81e in the same manner as in the second embodiment, and the members 80b to 80e are also inside the member from the reinforcing bars in the outer peripheral portion of the vertical section in the same manner as the divided portion 82b described above. As described above, the explosive is linearly arranged in the divided portions 82b to 82e. At this time, the members 80b and 80c may be perforated from the free surface from which the member 80a is removed as shown in FIG. 17, or the hole may be perforated from the side surface of the foundation beam 80 as shown in FIG. The members 80d and 80e are perforated from the side surface of the foundation beam 80.

  And blasting at each divided part at once. Then, cracks occur in the concrete at the divided portions 82b to 82e, and cracks also occur in the concrete inside the divided sections at the divided portions 81b to 81e. And the concrete inside the member parted in this way is extruded to the direction of a free surface by the blast of the parting parts 81b-81e.

  In addition, when the amount of explosives increases at the time of blasting, it is possible to level the noise and vibration by continuously blasting each member with a minute time difference using a stepped detonator. The blasting order at this time is, for example, blasting the dividing part (82b etc.) inside the reinforcing bar on the outer periphery of the vertical section of the member earlier than the dividing part (81b etc.) dividing the member in the vertical direction. The dividing part for dividing the member in the vertical direction may be blasted in order from the free surface of the central part toward the end (for example, in the order of 81b, 81d and 81c, 81e). Also in this case, cracks are generated in the concrete at the divided portions 82b to 82e, and cracks are also generated in the concrete inside the divided portions 81b to 81e. And the concrete inside the divided member is extruded in the direction of the free surface by the blasting of the dividing portions 81b to 81e.

  Also by the disassembly method of this embodiment, the effect similar to the disassembly method of the 1st-3rd embodiment is acquired. That is, it is possible to work in a small space compared to when a large breaker is used, noise and vibration can be reduced, and generation of noise and vibration can be suppressed instantly. Moreover, compared with the case where it cut | disconnects using a wire saw or a wall saw, it can also aim at reduction of a cost and a construction period. In addition, since the perforation diameter is reduced, a large-scale machine is not required, and noise, vibration, and dust are reduced. In addition, the possibility of interference with the reinforcing bar during drilling is small, and even if it interferes, the diameter is small and it is easy to escape. Further, when the hole is formed by drilling from the outer surface where at least a part of the reinforcing bar is exposed, the position of the reinforcing bar is known, so that the possibility of interference with the reinforcing bar is further reduced. This reduces the drilling cost.

  When blasting, a plurality of linear explosives can be appropriately arranged, and the target member can be most efficiently broken by using the minimum amount of explosive. In other words, since the minimum amount of explosives can be distributed almost evenly at the dividing part, the blasting energy can be used without waste for cracking and crushing of concrete, minimizing the amount of explosives used. For example, the amount of each hole used can be 50 g or less, preferably 30 g or less. This not only has the effect of suppressing noise, vibration, dust and the like, and also suppressing the scattering of stepping stones, but also provides an effect that the blasting section need only be covered with an explosion-proof sheet or the like. Including these, it is possible to improve workability and reduce costs throughout the dismantling process.

  In addition, since a linear explosive created by an electric detonator and a detonator is used, the explosive usage can be freely fine-tuned simply by adjusting the length of the detonator. No blasting with explosives. In addition, since the explosive wire is charged in the small-diameter hole, and the hole is sealed with inclusions such as sand, blasting occurs inside the member. Generation of vibration, dust, blast, etc. can be greatly suppressed.

  Note that the disassembly method described in the fourth embodiment is not limited to the foundation beam 80 described above, and can be applied to various members.

The preferred embodiments of the disassembly method according to the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited to such examples. It will be apparent to those skilled in the art that various changes or modifications can be conceived within the scope of the technical idea disclosed in the present application, and these naturally belong to the technical scope of the present invention. Understood.
For example, in the disassembling method of the present invention, it is only necessary to efficiently use blasting energy by appropriately arranging a plurality of linear explosives, and as long as it is limited to the arrangement of linear explosives shown above. It will never be done. For example, it may differ depending on the arrangement of reinforcing bars or the like.
The dismantling method of the present invention can also be applied to steel-framed reinforced concrete structures, steel pipe concrete structures, unreinforced concrete structures, and the like. For example, in a steel reinforced concrete structure, like the above, a plurality of explosives are provided in a line, and the explosive amount is placed near the inside of the outer periphery of the reinforcing bar to blast and split the concrete part. Etc. In addition, for steel pipe concrete structures and unreinforced concrete structures, multiple linear explosives may be placed inside the dividing cross section, and the others may be blasted in the same way to cut the concrete part. it can.

DESCRIPTION OF SYMBOLS 1 ......... Column 3, 31, 53, 55, 81a-81e, 82b ......... Parting part 5,32,56,83 ......... Concrete 7,33,84 ......... Axial rebar 9,35,59 , 85 ......... Strips 11, 12, 37, 39, 61, 63, 65, 67, 87, 89, 91, 93, 99 ... ... Holes 13, 41, 69, 95 ... ... Linear explosives 15 ......... Electrical detonator 17 ......... Explosion wire 19, 43, 71, 97 ......... Inclusion 30 ......... Beams 50, 51, 80a-80e ......... Member 57 ......... Horizontal rebar 80 ... ...... Foundation beam

Claims (11)

A demolition method for demolishing a concrete structure,
Perforating the concrete structure from the outer surface, and dividing the concrete structure, forming a plurality of holes from the outer surface toward the inside;
A step of arranging explosives linearly in the hole;
Performing the blasting with the explosive and dividing the concrete of the concrete structure at the dividing portion;
A disassembling method comprising: In the dividing part, reinforcing bars are arranged on the outer periphery of the dividing section along the dividing direction,
The hole portion is provided in the divided portion, in the vicinity of the inside of the reinforcing bar on the outer periphery of the divided section, and in the divided section,
2. When dividing the concrete by blasting with the explosive, the concrete around the reinforcing bars in the outer peripheral portion of the divided section is crushed and a crack is made to penetrate the concrete inside the divided portion. The dismantling method described.   The amount of the explosive provided in the hole near the inside of the reinforcing bar in the outer periphery of the dividing section is larger than the amount of the explosive provided in the hole inside the dividing section. The dismantling method according to claim 2.   The disassembling method according to claim 1, wherein the amount of explosive disposed in each of the holes is 50 g or less.   2. The disassembling method according to claim 1, wherein the diameter of the cross section of the hole is set to 20 mm or less. The explosive is disposed at a position deeper than a predetermined distance from the outer surface in the hole,
The disassembling method according to claim 1, wherein a inclusion is arranged at the predetermined distance from the outer surface in the hole. The hole is provided in a direction of a side of a divided section along the dividing direction at the dividing part,
The depth of the hole is about 2/3 of the length of the side corresponding to the direction of the hole, or about 200 mm shorter than the length of the side, or an intermediate length thereof. The dismantling method according to claim 1.   The demolition method according to claim 1, wherein the explosive is a linear explosive created by an electric detonator and a detonation wire. In the concrete structure, a reinforcing bar is arranged outside the part from the divided part,
2. The dismantling method according to claim 1, wherein when the concrete is divided by blasting with the explosive, a crack is made to penetrate the concrete in the divided portion inside the member from the reinforcing bar.   10. The dismantling method according to claim 9, wherein the hole is formed by drilling from an outer surface where at least a part of the reinforcing bar is exposed. When forming the hole portion, the hole portion is formed by a first dividing portion in which a reinforcing bar is arranged on the outer peripheral portion of the dividing section along the dividing direction and a second dividing portion in which the reinforcing bar is arranged outside the member. Forming multiple,
When dividing the concrete by blasting with the explosive, the first dividing part and the second dividing part are blasted to penetrate the concrete of the second dividing part and the first dividing part. 2. The dismantling method according to claim 1, wherein cracks are made to penetrate through the concrete inside the divided section and the divided concrete is pushed out in the direction of the outer surface of the concrete structure.

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