Method for toppling a tower structure utilizing a concrete foundation and a base flange

Abstract

To provide a towering structure overturning method which can reduce man-hours when preparing for overturning and after overturning, and prevent sudden (unexpected) overturning during construction, with which large external force is not necessary to initiate overturning.SOLUTION: Base flanges or similar foundations which are reinforced concrete base are used, and a horizontal cutting process, a notch creation process, a removal process, and a sensor installation process are carried out before execution of the overturning.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a method for toppling a tower structure such as a windmill for power generation, which utilizes a concrete foundation and a flange at the base or a reinforced concrete slab serving as a similar foundation to topple the tower structure for dismantling.

Background Art

[0002] Structure is dismantled due to aging deterioration or equipment replacement. In the case of a so-called tower structure with a certain height, it is standard to install a scaffold and successively cut it into small pieces from the top part at a high place and lower it by a crane or the like to the lower part in sequence, and finally remove the foundation part. Structure In order to reduce the high-altitude work in the above dismantling, improve the safety of workers, reduce man-hours, and achieve early dismantling, as techniques for toppling and dismantling tower structures, those disclosed in Patent Document 1 (method for toppling a regenerator of a hot blast stove) and Patent Document 2 (method for toppling a tower structure utilizing a foundation part) are known.

[0003] The technique disclosed in Patent Document 1 relates to a technique for realizing a safe toppling by reinforcing the base of a structure by some method to secure a toppling axis and then cutting out the structure itself to control the toppling direction. The technique disclosed in Patent Document 2 is a technique that has evolved from the problems of the technique of Patent Document 1 and relates to a technique for realizing a safe toppling by forming a strong toppling axis by cutting out a concrete foundation and controlling the toppling direction. The notches in Patent Documents 1 and 2 are less than half the size of the bottom. Even if cut out, the overall center of gravity is on the safer side than the toppling axis, and it is necessary to apply a force from the outside at the start of toppling, resulting in a forced toppling. For example, Patent Document 2 describes a method of pushing up with a jack.

Prior Art Documents

Patent Documents

[0004] ​

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] In Patent Document 1, a tipping axis is created by reinforcing the base, and in Patent Document 2, a tipping axis is created by taking advantage of the strength of the concrete foundation. Finding a strong tipping axis in the tipping method is the most important issue.

[0006] According to Patent Document 1, it is a method for disassembling a "regenerative furnace of a hot blast stove", which is a tower-shaped structure. By filling a filler in the lower part of the cylindrical regenerative furnace, the strength of the lower part of the regenerative furnace is increased, and when cutting out this part to carry out tipping, buckling due to insufficient strength is prevented, and by limiting the tipping direction, safe tipping is achieved.

[0007] However, the work of filling the filler takes a lot of man-hours, and waiting time occurs while the filler hardens. Also, at the final stage of disassembly, the filler becomes industrial waste.

[0008] According to Patent Document 2, without using "reinforcement of the cylindrical lower part" as in Patent Document 1, by taking advantage of the concrete foundation buried in stable ground, digging down to the concrete foundation, cutting out the concrete foundation to create a strong tipping axis, and limiting the tipping direction to achieve safe tipping.

[0009] However, the work of digging down to the concrete base also takes a lot of man-hours.

[0010] In the present invention, when a flange or a "reinforced concrete slab serving as a foundation" similar thereto can be found in the concrete foundation and the base, When the nuts are tightened against a number of bolts by which the disk (= flange) at the bottom of the column of the tower-like structure is firmly fixed to the concrete disk along the circumference,Make a notch larger than half of the bottom of the board so that the overall center of gravity is on the side of the axis of rotation in the direction of tipping. The bolts present in the notch part would be cut, but they are spared from being cut After creating a state where the stationary state is maintained by bolts, while holding the bolts on the axis of rotation, the bolts that are spared from cutting are pushed from the inside to the outside of the axis of rotation. At a certain point, the bolts that have not yet been cut by the tipping force cannot withstand it and are torn off, causing natural tipping to topple the tower structure.

Means for Solving the Problem

[0011] The invention according to claim 1 for achieving the above object is A foundation exposure step of exposing the lower part of the base flange by the minimum necessary amount for the notch for tipping, a horizontal cutting step of cutting the lower part of the base flange horizontally to a position determined in advance by calculation to be larger than half of the bottom in the horizontal direction, and obliquely from below the flange surface toward the central side cross-section of the horizontal cutting Above A notch creation step of cutting, a removal step of removing the notch portion, an installation step of installing a weight sensor and a support material in the notch portion, and using the intersection line of the horizontal cutting step and the notch creation step as the axis of rotation to topple the tower Structure together with the base flange, and has a toppling step.

[0012] According to this configuration, there is no need to "fill with a filler and dispose of it later" as in Patent Document 1, nor is it necessary to "dig down to the huge base buried in the ground" as in Patent Document 2. The tower structure can be easily, safely, and quickly toppled using a strong part that is a part of the structure called the base flange as the axis of rotation.

[0013] In this toppling, a strong part that is originally a part of the structure called the base flange is utilized as the strength of the axis of rotation (tipping fulcrum), so it can resist buckling and topple the tower Structure in the planned direction, which is safe.

[0014] The invention according to claim 2 is characterized in that the overall center of gravity is moved to the side of the tipping axis on the tipping side, and the bolts are sequentially cut from the state of being restrained only by the tension of the remaining bolts, At a certain point, when the remaining bolts cannot withstand the overturning force and are pulled off, and the structure is allowed to tip over naturally without applying a large external force.

[0015] The invention according to claim 3 is characterized in that a weight sensor is installed in the notch and monitored, so as to obtain a precursor of a sudden tip-over (unexpected tip-over) during construction, and the bolt disconnection in the tipping process is adjusted numerically rather than by intuition or experience. As the center of gravity is on the tipping side of the tipping axis as described in claim 2, a sudden tip-over is more likely to occur compared to the case where the center of gravity is on the safe side as in the existing patents. Therefore, such countermeasures are taken.

Advantages of the Invention

[0016] According to the present invention, the lower part of the base flange is cut horizontally, and further a notch is made obliquely upward from the lower part thereof and removed. By tipping the tower-like structure with the intersection line of the horizontal cut and the obliquely upward cut as the tipping axis, the tower-like structure can be tipped over simply.

[0017] By making the notch at the bottom larger than half, moving the overall center of gravity to the tipping side of the tipping axis and maintaining the stationary state with the tension of the remaining bolts, and then cutting the bolts from that state, natural tipping can be carried out without the need for a large external force.

[0018] By installing and monitoring a weight sensor, a sudden tip-over (unexpected tip-over) during construction can be predicted. Tipping can be carried out without the need for "unnecessary reinforcement" or "large-scale excavation of the ground" as in Patent Document 1 and Patent Document 2.

Brief Description of the Drawings

[0019]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 8

Embodiments for Carrying Out the Invention

[0020] Next, embodiments of the present invention will be described in detail with reference to the drawings. A method of toppling a tower-like structure to be toppled for disassembling the tower-like structure will be described with reference to FIGS. 1 to 8. FIG. 1 is a side view showing a tower-like structure according to an embodiment of the present invention, FIG. 2 is a diagram showing the cutting, notching, and toppling axis of the base flange and its periphery of the method of toppling the tower-like structure, and FIG. 3 is a diagram showing bolt cutting in the toppling process according to this embodiment.

[0021] As shown in FIG. 1, in this embodiment, the tower-like structure 10 is a wind turbine for power generation. However, as will be described later, the tower-like structure of the present invention is not limited to a wind turbine for power generation.

[0022] What is described as the "base flange" is a general term for the "reinforced concrete slab serving as the foundation", and the shape is not limited to that shown in FIG. 2.

[0022] The tower-like structure 10 is connected to the base flange via a tower 12, and the base flange is fixed to the foundation 13 with bolts or the like.

[0023] Next, each step of the method of toppling the tower-like structure of the present invention will be described. The method of toppling the tower-like structure of the present invention includes a foundation exposure step, a horizontal cutting step, a notch creation step, a removal step, a sensor installation step, and a toppling step.

[0024] [Foundation Exposure Step] When the base part is not exposed enough for the notch creation step described later, dig around as much as necessary to create an exposed part.

[0025] [Horizontal cutting process] Next, perform a horizontal cut under the base flange. This cut is made up to a distance 21 determined in advance by calculation. This distance is larger than the radius of the bottom. The cut can be made using, for example, a wire saw or the like.

[0026] [Notch creation process] Next, make a cut obliquely upward from below the cut surface toward the central cutting line 22 to create a notch. The cut can be made using, for example, a wire saw or the like.

[0027] [Removal process] Next, remove the notch portion created in the notch process. The removal can be carried out, for example, by fixing a wire rope (not shown in the figure) to the notch portion 23 and pulling the other end with a winch or the like.

[0028] [Sensor installation process] Install a load sensor in the notch portion, monitor the pressure applied from above the notch portion, and adjust it so that it does not exceed 0, so that even when the overall center of gravity is on the tipping side, it can be maintained stationary by the remaining bolts or the like. This may be, as shown in FIG. 3, a "hanging rod type with a load sensor and a support material", and without sticking to this, it is sufficient if the pressure can be observed. For example, a general-purpose heavy machine with a load sensor may be used as a substitute.

[0029] [Tipping process] Next, there is the tipping process. In the present invention, since the center of gravity position is on the tipping side, as described above, a strong external force resistant to tipping is not required. In order to hold the bolts 31 corresponding to the tipping axis (two on the left and right are held in the figure, but any number can be used depending on the situation) and prevent the tipping axis from shaking and maintain the strength, avoid the periphery of this bolt and cut horizontally from the inside to the outside under the base flange surface to sequentially cut the remaining bolts (see FIG. 3). This is performed remotely by a wire saw not shown in the figure, so that it can be realized even if the operator is not near the site immediately before tipping, which is also beneficial for ensuring the safety of the operator.

[0030] In addition, in the wind turbine for power generation shown in FIG. 1, the center of gravity is not always at the center of the support column, and there are cases where the center of gravity is difficult to determine. Even in such cases, a safe fall can be achieved by making the direction of fall not in the direction of the rotation axis of the wind turbine (front or back), but in a direction perpendicular to the rotation axis of the wind turbine, that is, falling sideways.

[0031] In the above embodiment, a wind turbine for power generation is exemplified as the tower-like structure, but it is not limited to this, and any tower-like structure having a base flange or a reinforced concrete slab serving as a foundation similar thereto may be used. Structure For example, various other tower-like structures can be mentioned, such as a concrete self-supporting chimney 40 (FIG. 4), a distillation column 50 (FIG. 5), a pressure reaction column 60 (FIG. 6), a steel tower-supported chimney 70 (FIG. 7), and a tripod self-supporting chimney 80 (FIG. 8).

Description of Reference Numerals

[0031] 10 Tower-like structure 12 Tower 13 Base 20 Base flange 21 Distance determined by calculation 22 Central side cutting line (= axis of fall) 23 Notch 31 Bolt 32 Wire saw (only the wire is shown in the figure) 33 Weight sensor

Claims

1. A method of implementing a toppling while utilizing a concrete foundation and a base flange, comprising: a foundation exposure step of exposing the minimum necessary portion under the base flange for a notch for toppling; a horizontal cutting step of horizontally cutting under the base flange to a position calculated in advance to be larger than half of the bottom in the horizontal direction; a notch creation step of cutting obliquely upward from below the base flange toward the central side cross-section of the horizontal cutting; a removal step of removing the notch portion; a sensor installation step of installing a weight sensor and a support material in the notch portion; and a toppling step of toppling the tower structure together with the base flange with the intersection line of the horizontal cutting step and the notch creation step as the toppling axis. A method of toppling a tower structure, characterized by creating a strong toppling axis and toppling it by utilizing a concrete foundation and a base flange.

2. The method of toppling a tower structure according to claim 1, characterized in that the overall center of gravity is moved to the toppling side of the toppling axis, bolts existing in the notch portion are cut off by the removal step, but the bolts are sequentially cut starting from a state where the remaining bolts that are not cut off are held only by the tension, and at a certain point, the remaining bolts cannot withstand the toppling force and are pulled off, causing natural toppling without applying a large external force.

3. The method of toppling a tower structure according to claims 1 and 2, characterized in that a weight sensor is installed in the notch portion and monitored to obtain a precursor of a sudden toppling (unexpected toppling) during construction, and the "bolt separation" of sequentially cutting bolts starting from a state where the remaining bolts that are not cut off are held only by the tension during the toppling step is adjusted numerically without relying on intuition or experience.

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