Disassembly method

Abstract

The present invention provides a demolition method and the like that can prevent a decrease in slab cutting efficiency. In the present invention, a support beam 300 is provided on the underside of a slab 100-1 to be demolished, and the support beam 300 is supported by shoring 200. The slab 100-1 to be demolished is separated from existing slabs 100-2 on both sides so that the cross section of the slab 100-1 in the thickness direction becomes a trapezoid with the long side at the top, and the slab 100-1 to be demolished together with the support beams 300 is lifted upward and removed. When supporting the support beams 300 with the shoring 200, a height adjustment mechanism 203 of the shoring 200 is used to apply a vertical compressive force to the shoring 200. When the slab 100-1 to be demolished is separated from the existing slabs 100-2 on the side, the upper surface of the slab 100-1 to be demolished is pushed up above the upper surfaces of the existing slabs 100-2 on the side.

Description

[Technical Field]

[0001] The present invention relates to a disassembly method and the like. [Background technology]

[0002] Patent Document 1 describes a block demolition method for demolishing a building, in which the building is cut into large components (blocks) and then lifted and removed by a crane.

[0003] In Patent Document 1, support beams are installed on the underside of the slab to be demolished, and while the support beams are supported from below by shoring, the slab to be demolished is separated from the existing slabs on both sides, and the slab to be demolished is lifted upward together with the support beams using a lifting jig and removed.

[0004] In Patent Document 1, the slab to be demolished and the support beams are integrated and lifted by a crane, allowing the slab to be removed. This allows the support beams to prevent the slab from bending or breaking during lifting. This makes it possible to demolish larger slabs. Furthermore, the slab to be demolished is cut diagonally from the existing slabs on both sides so that the cross section of the slab in the thickness direction is trapezoidal with the long side facing up. This allows the slab to be supported by the existing slabs on both sides. Therefore, the support structure can be removed immediately after the slab is cut, eliminating the need to leave it in place for long periods of time. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2022-183869 Summary of the Invention [Problem to be solved by the invention]

[0006] However, with the method of Patent Document 1, when cutting a slab at an oblique cutting plane, the load of the slab to be demolished, etc., causes the support structure to shrink vertically, which raises concerns that the blade of the slab cutter may become pinched between the lowered slab to be demolished and the existing slab below the cutting plane, reducing the efficiency of cutting the slab.

[0007] The present invention has been made in consideration of the above problems, and aims to provide a dismantling method etc. that can prevent a decrease in slab cutting efficiency. [Means for solving the problem]

[0008] In order to solve the above-mentioned problems, the present invention provides a demolition method comprising the steps of: forming holes in a slab to be demolished; providing support beams on the underside of the slab to be demolished at positions corresponding to the holes and supporting the support beams with shoring installed on an installation surface; separating the slab to be demolished from the existing slabs on both sides so that the cross section of the slab in the thickness direction is a trapezoid with the long side of a pair of parallel sides at the top; and, after removing the shoring, lifting the slab to be demolished together with the support beams upward and removing them using a lifting jig installed using the holes. When supporting the support beams with the shoring, a height adjustment mechanism of the shoring is used to apply a vertical compressive force to the shoring, so that when the slab to be demolished is separated from the existing slabs on either side of the slab to be demolished, the upper surface of the slab to be demolished is pushed up above the upper surfaces of the existing slabs on the sides.

[0009] In the demolition method of the present invention, the use of the support beams allows for larger slabs to be demolished. Furthermore, the slab to be demolished is separated from the existing slabs on both sides so that its cross section in the thickness direction becomes the trapezoidal shape described above, allowing the slab to be supported by the existing slabs on both sides. Furthermore, in the present invention, a support height adjustment mechanism is used to apply a vertical compressive force to the support supporting the slab to be demolished, so that when the slab is separated from the existing slabs on its sides, the slab is pushed up higher than the existing slabs on its sides. This prevents the blade that cuts the slab diagonally from becoming pinched between the slab to be demolished and the existing slab, preventing a decrease in slab cutting efficiency.

[0010] The plane of the slab to be demolished is rectangular, and has a set of approximately parallel first sides and a set of approximately parallel second sides, and the slab to be demolished is separated from the existing slabs on both sides in the direction of the first sides so that the cross section along the direction of the first sides becomes a trapezoid, and it is desirable that the slab to be demolished is separated from the existing slabs on both sides in the direction of the second sides so that the cross section in the thickness direction of the slab to be demolished along the direction of the second sides has one end in the vertical direction and the other end in the direction of the second sides slopes downward and inward. By making the cross section of the slab to be demolished along the first edge of the slab into the trapezoidal shape, the slab can be supported by existing slabs on both sides of the first edge. Therefore, the end of the slab along the second edge of the slab can be cut vertically, reducing the area of ​​the cut surface and improving cutting speed. However, cutting both ends vertically can make lifting the slab difficult due to construction errors such as slab sagging at the cut surface or misalignment of the cut surface relative to the vertical direction. Therefore, in this invention, one end of the second edge is cut vertically, but the other end is cut so that it slopes downward and inward. This prevents difficulties in lifting the slab to be demolished.

[0011] The oblique side of the trapezoid is inclined at, for example, about 30 degrees relative to the vertical direction. This allows for stable support of the slab to be demolished by the existing slab, while also achieving good slab cutting speed.

[0012] The planar shape of the slab to be demolished is rectangular, and the slab to be demolished is desirably separated from the existing slabs on both sides in the short side direction so that the cross section of the slab to be demolished along the short side direction becomes the trapezoid. The slab to be demolished is, for example, a deck slab in which concrete is provided on a deck plate having a cross section with alternating successive peaks and valleys, and the successive direction of the successive peaks and valleys corresponds to the long side direction of the slab to be demolished. This allows the slab to be supported along its long side from the existing slab, increasing the support area from the existing slab and thereby stably supporting the slab. If the slab to be demolished is a deck slab with peaks and valleys on its underside, by aligning the continuation direction of the peaks and valleys with the long side direction of the slab to be demolished, it is possible to prevent the support area of ​​the slab to be demolished from changing depending on the position of the cut surface. [Effects of the Invention]

[0013] The present invention can provide a dismantling method and the like that can prevent a decrease in slab cutting efficiency. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 shows a slab 100. [Figure 2] A diagram showing shoring 200 and support beams 300. [Figure 3] 2A to 2C are diagrams illustrating height adjustment by a height adjustment mechanism 203. [Figure 4] 1A and 1B are diagrams illustrating cutting of the slab 100. FIG. [Figure 5] A diagram showing a cross section of the slab in the thickness direction near the cutting plane C. [Figure 6]FIG. 10 is a diagram showing the top surface of the slab 100-1 to be demolished. [Figure 7] 1 is a diagram showing a cross section of the slab thickness direction along the long side direction of the slab 100-1 to be demolished. [Figure 8] 10A and 10B are diagrams showing the removal procedure of the slab 100-1 to be demolished using the lifting jig 1. FIG. [Figure 9] FIG. 1 shows a slab 100a. DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

[0016] In a demolition method according to an embodiment of the present invention, a slab 100 shown in Fig. 1(a) is demolished. Fig. 1(a) is a diagram showing the top surface of the slab 100. Fig. 1(b) is a diagram showing a cross section of the slab 100 in the thickness direction (hereinafter referred to as the slab thickness direction) taken along line aa in Fig. 1(a). The slab 100 is a plate-like member made of concrete supported by a pair of beams 101 arranged in parallel.

[0017] When demolishing, first, holes 102 are formed through the thickness of the slab 100 (the slab to be demolished, which will be described later). The holes 102 are holes for attaching a hanging jig, which will be described later, and their diameter is set to be larger than the width of the support beams, which will be described later. A plurality of holes 102 are formed near the inside of a pair of beams 101, spaced apart along the beam axis direction of each beam 101. The beam axis direction corresponds to the up-and-down direction in FIG. 1(a) and the normal direction to the paper surface in FIG. 1(b).

[0018] Thereafter, as shown in Figures 2(a) and 2(b), a temporary cover 103 is placed over the hole 102 to perform temporary open curing. Figure 2(a) is a diagram showing the top surface of the slab 100, and Figure 2(b) is a diagram showing a cross section of the slab in the thickness direction along line aa in Figure 2(a).

[0019] Additionally, temporary support beams 300 parallel to the beam axis direction of the beams 101 are placed on the underside of the slab 100 in alignment with the positions of the holes 102 in the slab 100, and each support beam 300 is supported from below by shoring 200 installed on the installation surface 10. The support beams 300 are truss-shaped members with diagonal members between the upper chord and the lower chord, similar to the support beams described in JP 2022-183869 A, for example, and are made of wood. However, the shape and material of the support beams 300 are not limited to this.

[0020] The support structure 200 is made up of multiple vertical members 201 arranged at intervals in the direction orthogonal to the beam axis of the beam 101 and in the beam axial direction, and adjacent vertical members 201 in each direction are connected by horizontal cross members 202. The beam axis orthogonal direction is the direction perpendicular to the beam axial direction on a plane, and corresponds to the left-right direction in Figures 2(a) and 2(b).

[0021] A height adjustment mechanism 203 is provided at the upper end of the vertical member 201, and the support beam 300 is supported via the height adjustment mechanism 203. In addition, the upper and lower horizontal members 202 are connected to each other by diagonal members 204.

[0022] The height adjustment mechanism 203 may be, for example, a screw-type height adjustment jack (screw jack). With the upper end of the height adjustment mechanism 203 in contact with the underside of the support beam 300, the height is adjusted in a direction that increases the height of the upper end of the height adjustment mechanism 203. As a result, the upper end of the height adjustment mechanism 203 remains in contact with the underside of the support beam 300, but a vertical compressive force is applied to the vertical member 201 of the shoring 200. As shown in FIG. 3 , the height adjustment amount of the height adjustment mechanism 203 can be managed by checking the thread pitch p (mm) of the height adjustment jack in advance and using the number of threads n. In other words, if the number of threads visible from the outside increases by Δn, the height adjustment is performed in a direction that increases the height of the upper end of the height adjustment mechanism 203 by p × Δn (mm), and a compressive force of that amount is applied to the vertical member 201.

[0023] In this embodiment, the slab 100 is supported from below by the support beams 300 and the shoring 200, and the slab 100 is cut with a slab cutter (not shown) as shown in Figure 4. Figure 4 shows a cross section of the slab in the thickness direction corresponding to Figures 1(b) and 2(b). Symbol C in Figure 4 is the cut surface of the slab 100, and the slab 100 is cut diagonally between the hole 102 and the beam 101, from the beam 101 side toward the hole 102 side as it goes downward.

[0024] As a result, the slab 100-1 to be demolished, which is located inside the cutting plane C, is separated from the slabs 100-2 on either side (hereinafter referred to as the existing slabs) so that the cross section of the thickness direction of the slab 100-1 becomes a trapezoid with the long side of a pair of parallel sides facing up.

[0025] 5(a) to 5(c) are diagrams showing a cross section of the slab in the thickness direction near the cutting surface C. In this embodiment, the inclination angle α of the cutting surface C with respect to the vertical direction (the smaller of the angles formed by the direction of the cutting surface C in the above cross section and the vertical direction) is set to approximately 30 degrees. "Approximately 30 degrees" means that even if the inclination angle α of the cutting surface C is set to 30 degrees in the planning stage, there may be an error from 30 degrees during actual construction, and this includes such construction error.

[0026] In this embodiment, when the slab 100-1 to be demolished is separated from the existing slab 100-2 to the side as shown in Fig. 5(a), the restoring force generated in the vertical members 201 of the support 200 in a compressed state pushes the upper surface of the slab 100-1 to be demolished slightly (for example, about 2 to 3 mm) above the upper surface of the existing slab 100-2 to the side as shown in Fig. 5(b). Therefore, the blade 2 of the slab cutter that cuts the slab 100 is not pinched between the slab 100-1 to be demolished and the existing slab 100-2 below the cutting surface C, and a decrease in the cutting efficiency of the slab 100 can be prevented.

[0027] FIG. 6 is a diagram showing the top surface of the slab 100-1 to be demolished. In this embodiment, the plane of the slab 100-1 to be demolished is rectangular, with a pair of approximately parallel short sides 110 (first sides) and a pair of approximately parallel long sides 120 (second sides), and the slab 100 is cut along each side. "Approximately parallel" means that even if the sides are parallel in the plan, errors may occur during actual construction, and such construction errors are included. The cross section in FIG. 4 is a cross section along the short side direction of the slab 100-1 to be demolished, and the slab 100-1 to be demolished is separated from the existing slabs 100-2 on both sides of the short side direction so that the cross section has the trapezoidal shape described above.

[0028] Regarding the long side direction of the slab 100-1 to be demolished, as shown in Fig. 7(a) which is a schematic cross section in the thickness direction of the slab, if both ends of the long side direction are cut vertically and separated from the existing slab 100-2 on both sides of the long side direction, the cutting speed will improve because the area of ​​the cut surface C will be smaller. However, due to construction errors such as the slab's abutment at the cut surface C or a deviation of the cut surface C from the vertical direction, there is a risk that the slab 100-1 to be demolished will get caught when being lifted upward, making it difficult to lift.

[0029] Therefore, in this embodiment, as shown schematically in FIG. 7(b), one end of the long side (corresponding to the right side of FIG. 7(b)) is cut vertically, while the other end (corresponding to the left side of FIG. 7(b)) is cut so that it slopes downward and inward. This allows lifting to be performed diagonally upward toward the other end, as indicated by arrow b, and does not make it difficult to lift the slab 100-1 to be demolished. "Inside" refers to the center of the plane of the slab 100-1 to be demolished. Note that it is also possible to cut both ends of the long side of the slab 100-1 to be demolished so that they slope downward and inward, as in the example of FIG. 4. In this case, lifting the slab 100-1 to be demolished will not be difficult, but the cutting speed will be reduced because the area of ​​the cut surface C at one end of the long side of the slab 100-1 will be larger.

[0030] In this embodiment, after separating the slab 100-1 to be demolished from the existing slab 100-2, the lid 103 is removed, and the hoisting jig 1 is attached to the slab 100-1 to be demolished and the support beam 300 on its underside using the hole 102, as shown in FIG. 8(a). The hoisting jig 1 described in JP 2022-183869 A can be used, but is not limited to this. The hoisting jig described in JP 2022-183869 A comprises an upper member that is placed above the hole 102 and engaged with the upper surface of the slab 100-1 to be demolished, and a lower member that is placed below the support beam 300, and these are detachably connected to an intermediate member that is placed above the support beam 300.

[0031] Thereafter, the shoring 200 is removed as shown in Figure 8(b). The lifting jig 1 prevents the slab 100-1 to be demolished and the support beams 300 from falling when the shoring 200 is removed. Furthermore, the slab 100-1 to be demolished is supported by the existing slabs 100-2 on both sides, allowing the slab 100-1 to be demolished to be left alone for the time being. This allows the shoring 200 to be removed early, allowing other work to be carried out ahead of schedule and the landslide to be carried out.

[0032] FIG. 5(c) shows a cross section of the slab in the thickness direction near the cut surface C after the shoring 200 has been removed. The load of the slab 100-1 to be demolished is supported by the adjacent existing slab 100-2. When the inclination angle α of the cut surface C is 45 degrees, the ratio of the vertical reaction force V to the horizontal reaction force H generated in the existing slab 100-2 is 1:1. When the inclination angle α exceeds 45 degrees, the proportion of the horizontal reaction force H decreases, which is advantageous in that the horizontal force acting on the beam 101 decreases. However, this increases the area of ​​the cut surface C and reduces the cutting speed of the slab cutter. Therefore, in this embodiment, in order to minimize the area of ​​the cut surface C while ensuring structural stability, the inclination angle α of the cut surface C is reduced to approximately 30 degrees, making the cut surface C closer to the vertical.

[0033] However, the inclination angle α is not limited to this, and can be determined based on the position of the beam 101 in the structure, the distance between the beam 101 and the cutting surface C, etc., and may be a value other than 30 degrees and smaller than 45 degrees. The inclination angle α can also be made larger than 45 degrees, which has the advantage of reducing the horizontal force acting on the beam 101, as described above.

[0034] In this embodiment, after removing the shoring 200 as shown in Figure 8(b), the slab 100-1 to be demolished is lifted up by a crane (not shown) using a sling on the lifting jig 1 as shown in Figure 8(c), and then lowered onto a bolster 5 placed on the floor or the like and temporarily placed there as shown in Figure 8(d). Thereafter, the lifting jig 1 and the support beam 300 are removed from the slab 100-1, and the slab 100-1 is crushed and removed using heavy machinery or the like.

[0035] In this embodiment, the slab 100-1 to be demolished and the support beam 300 can be integrated and lifted by a crane, and the slab 100-1 can be removed, so that the support beam 300 can prevent the slab 100-1 from bending or breaking during lifting. Therefore, it is possible to dismantle the slab 100-1 in a larger size.

[0036] As described above, in this embodiment, the height adjustment mechanism 203 of the shoring 200 is used to apply a vertical compressive force to the vertical members 201 of the shoring 200 supporting the slab 100-1 to be demolished, so that when the slab 100-1 is separated from the existing slab 100-2 to the side, the slab 100-1 is pushed up higher than the existing slab 100-2 to the side. This prevents the blade 2 that cuts the slab 100 diagonally from being pinched between the slab 100-1 to be demolished and the existing slab 100-2, preventing a decrease in the cutting efficiency of the slab 100.

[0037] In this embodiment, by forming the cross section of the slab 100-1 to be demolished along its short side into the trapezoidal shape, the slab 100-1 to be demolished can be supported by the existing slabs 100-2 on both sides of the short side. Therefore, the long side ends of the slab 100-1 to be demolished can be cut vertically, reducing the area of ​​the cut surface C and improving the cutting speed. However, if both long side ends are cut vertically, construction errors such as the slab 100's abutment at the cut surface C or misalignment of the cut surface C relative to the vertical direction may make it difficult to lift the slab 100-1 to be demolished. Therefore, in this embodiment, one long side end is cut vertically, but the other end is cut so that it slopes downward and inward. This prevents the slab 100-1 to be demolished from becoming difficult to lift.

[0038] In addition, in this embodiment, by setting the inclination angle α of the cutting surface C (the hypotenuse of the trapezoidal cross section of the slab 100-1 to be demolished) to approximately 30 degrees, it is possible to achieve both stable support of the slab 100-1 to be demolished by the existing slab 100-2 and good cutting speed of the slab 100.

[0039] In addition, in this embodiment, the slab 100-1 to be demolished is supported along its long side by the existing slab 100-2, and the support area from the existing slab 100-2 is increased, thereby enabling the slab 100-1 to be stably supported.

[0040] However, the present invention is not limited to the above-described embodiment. For example, the slab 100 may be a deck slab in which concrete is provided on a horizontal deck plate (flat deck). In this case, not only the concrete but also the deck plate is cut during demolition. As shown in FIG. 9(a), the slab 100a may also be a deck slab in which concrete 140 is provided on a deck plate 130 having a cross-sectional shape with alternating peaks and valleys. In this case, the concrete 140 and the deck plate 130 are also cut during demolition.

[0041] In the example of Figure 9(a), the continuous direction of the peaks and valleys on the underside of the slab 100a-1 to be demolished is set to the long side direction of the slab 100a-1 to be demolished. As a result, even if the position of the cutting plane C changes as shown by the dashed line, the area of ​​the cutting plane C, i.e., the support area from the existing slabs on both sides of the short side direction of the slab 100a-1 to be demolished, does not change. For example, as shown in Figure 9(b), if the continuous direction of the peaks and valleys on the underside of the slab 100a-1 to be demolished is set to the short side direction of the slab 100a-1 to be demolished, the area of ​​the cutting plane C, i.e., the support area from the existing slabs, will change as the position of the cutting plane C changes as shown by the dashed line, and the impact of errors in the cutting position of the slab 100a will be significant.

[0042] Furthermore, the planar shape of the slabs 100-1, 100a-1 to be demolished is not limited to a rectangular shape, and may be a square or other rectangular shape. The arrangement of the support beams 300 is also not particularly limited, and for example, the support beams 300 may be arranged in a rectangular frame shape. Furthermore, if an existing beam (not shown) is in a suitable position and can be used as a support beam, it is possible to support the beam with shoring 200 when cutting the slab 100, and to support the slab 100 to be demolished using the existing beam and shoring 200.

[0043] While the preferred embodiments of the present invention have been described above with reference to the accompanying drawings, the present invention is not limited to these examples. It is clear that those skilled in the art can conceive of various modifications or alterations within the scope of the technical ideas disclosed herein, and it is understood that these modifications also fall within the technical scope of the present invention. [Explanation of symbols]

[0044] 10: Installation surface 100, 100a: Slab 100-1, 100a-1: Slabs (to be demolished) 100-2: Existing slab 102: Hole 110: Short side 120: Long side 130: Deck plate 140: Concrete 200: Shoring 201: Vertical material 203: Height adjustment mechanism 300: Support beam

Claims

1. forming a hole in a slab to be demolished; A step of providing a support beam on the underside of the slab to be demolished at a position corresponding to the hole, and supporting the support beam with a support installed on an installation surface; A process of separating the slab to be demolished from the existing slabs on both sides so that the cross section of the slab in the thickness direction is a trapezoid with the long side of a pair of parallel sides facing up; After removing the support, the slab to be demolished is lifted upward together with the support beam using a lifting jig arranged using the hole, and removed; and When supporting the support beam with the support, a height adjustment mechanism of the support is used to apply a vertical compressive force to the support, A demolition method characterized in that, when the slab to be demolished is separated from the existing slab to the side of the slab to be demolished, the upper surface of the slab to be demolished is pushed up above the upper surface of the existing slab to the side.

2. The plane of the slab to be demolished is rectangular and has a set of substantially parallel first sides and a set of substantially parallel second sides, The slab to be demolished is The slab is separated from the existing slabs on both sides in the direction of the first side so that the cross section along the direction of the first side becomes the trapezoid; The demolition method described in claim 1, characterized in that the thickness cross section of the slab to be demolished along the direction of the second side is separated from the existing slabs on both sides in the direction of the second side so that one end in the direction of the second side is vertical and the other end in the direction of the second side is inclined downward and inward.

3. 2. The disassembly method according to claim 1, wherein the oblique side of the trapezoid is inclined at about 30 degrees relative to the vertical direction.

4. The plane of the slab to be demolished is rectangular, The demolition method according to claim 1, characterized in that the slab to be demolished is separated from the existing slabs on both sides in the short side direction so that the cross section along the short side direction of the slab to be demolished becomes a trapezoid.

5. The slab to be demolished is a deck slab in which concrete is provided on a deck plate having a cross-sectional shape in which peaks and valleys alternate continuously, The demolition method according to claim 4, wherein the direction in which the peaks and valleys continue corresponds to the direction of the long sides of the slab to be demolished.

Images