JP2004270295A - Method of excavating concrete body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of excavating a concrete body with good efficiency without worsening the environment. <P>SOLUTION: The method of excavating the concrete is comprised of a first step of drilling a U-shaped continuous hole 4 in a cutting face 3 of the concrete body 1 by core boring; a second step of drilling individual holes 5 between both edges of the U-shaped continuous hole 4; and a third step of inserting a hydraulic jack into the individual holes 5 to form a crack 8 connecting between both the ends of the U-shaped continuous hole, forming a crack 9 containing the bottom of the continuous hole 4, and cutting away a concrete mass 6 defined by the continuous hole 4 and the two cracks 8, 9. The concrete mass 6 formed like a block can be cut away by the continuous hole 4 and the cracks 8, 9, and therefore the troublesome work of crushing the concrete mass 6 is eliminated, thus leading to the efficient excavation of the concrete body 1. Further, noise, vibrations, and mine dust generation can be suppressed. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for excavating concrete.
[0002]
[Prior art]
In recent years, redevelopment to increase or improve water intake facilities and discharge facilities in existing concrete dams has been promoted, and construction work has been newly performed on existing concrete dam embankments. In order to drill cavities, such as intakes and discharge pipes, in a dam embankment, excavation is often performed with a free-section tunnel excavator. This method is excellent in workability and can shorten the work period.
[0003]
In addition, a small continuous hole is drilled with a core boring device along the outer circumference of the face to separate the internal concrete from the embankment so that the impact and vibration are not applied to the dam embankment, and then the internal concrete is broken with a breaker There was also a method of crushing and carrying out fragments.
[0004]
There is also a method of cutting out the upper part of a concrete body into a block shape using a static crushing material (for example, Patent Document 1).
[0005]
[Patent Document]
JP 2000-309920 A
[Problems to be solved by the invention]
However, the construction method using a free-section tunnel excavator increases construction costs. Further, when crushing is performed by a breaker, noise, vibration, and dust are generated, and there is a fear that the environment is deteriorated. In addition, since the concrete is crushed finely, the excavation speed is low, and it is necessary to collect and remove finer pieces, which is complicated.
[0007]
In the method of cutting and removing concrete in a block shape, since no breaker is used, noise, vibration and dust can be suppressed, and work efficiency can be improved. However, the method of Patent Document 1 cuts out a concrete structure from the outer periphery, and thus cannot be directly applied when drilling a dam embankment.
[0008]
An object of the present invention is to provide a method for excavating a concrete body with high working efficiency without deteriorating the environment.
[0009]
[Means for Solving the Problems]
In order to solve the above problems, the invention according to claim 1 of the present invention relates to a method for excavating a concrete body, for example, as shown in FIG. A first step of drilling the hole 4, a second step of drilling a single hole 5 between both ends of the U-shape of the continuous hole 4, and inserting a hydraulic jack into the single hole 5 to form the two ends of the U-shape A third step of forming a crack 8 communicating between the two and forming a crack 9 including the bottom of the continuous hole 4 and cutting out the concrete mass 6 surrounded by the continuous hole 4 and the two cracks 8, 9. It is characterized by the following.
[0010]
According to the first aspect of the present invention, the U-shaped continuous hole 4 formed by core boring, the crack 8 formed by a hydraulic jack between the two ends of the U-shaped hole, and the crack 9 including the bottom of the continuous hole 4 are formed. Since the concrete block 6 can be cut out in a block shape, the concrete body 1 can be efficiently excavated without the trouble of crushing the concrete block 6. Further, generation of noise, vibration, and dust can be suppressed.
[0011]
The invention according to claim 2 is a method for excavating a concrete body, in which, for example, as shown in FIG. 2, a first step of drilling a continuous hole 4 in a U-shape in a face 3 of a concrete body 1 by core boring, A second step of inserting a wire saw (wire 7) into the bottom of the continuous hole 4 and cutting the concrete block 6 surrounded by a U-shape into a wedge shape by the wire saw 7 is characterized.
[0012]
According to the second aspect of the present invention, the concrete block 6 can be cut into a wedge shape from the U-shaped continuous hole 4 formed by core boring with a wire saw.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the concrete excavation method of the present invention will be described in detail.
FIG. 1 is a view showing the vicinity of a face 3 of a cavity 2 formed by removing a part of a concrete body 1 such as a dam embankment by the method of the present invention. In the figure, the cavity 2 is a square having a height of about 2 m and a width of about 2 m. In the direction of excavation of the face 3, a concrete mass 6 to be excavated is indicated by a broken line. In addition, on the wall surface on the downstream side of the dam embankment 1, a work stand (not shown) for performing a drilling operation is installed.
[0014]
Next, the first concrete excavation method of the present invention will be described.
First, a U-shaped continuous hole 4 is excavated in the face 3 of the cavity 2 using a core boring device. The continuous hole 4 is formed by continuously drilling a single hole having a diameter of about 150 to 200 mm as shown in FIG.
[0015]
Next, one or more single holes 5 are drilled between both ends of the continuous hole 4. The single hole 5 has a diameter of about 150 to 200 mm and can be formed using a core boring device.
[0016]
Next, the hydraulic jack is inserted into the single hole 5. By operating the hydraulic jack with hydraulic pressure, small crushing is performed, and a crack 8 connecting the U-shaped ends of the continuous hole 4 and the single hole 5 is generated. When the crack 8 is formed, a pressure plate is applied to the single hole 5 and the hydraulic jack is operated to spread the crack 8. At this time, a crack 9 is formed on the surface including the bottom of the continuous hole 4, and the concrete mass 6 to be excavated and the concrete body 1 are sheared.
[0017]
Next, the concrete mass 6 cut out from the inside of the cavity 2 is removed using a U-bolt previously attached to the concrete mass 6 with a chemical anchor.
The sheared surface obtained by cutting the concrete mass 6 from the concrete body 1 becomes a new face 3. The above operation is repeated to form the cavity 2 reaching the wall surface on the opposite side of the concrete body 1.
[0018]
According to the first concrete excavation method, since the concrete mass 6 can be cut out in a block shape by the U-shaped continuous holes 4, cracks, and shear surfaces, the concrete mass 6 can be efficiently crushed without the need for crushing. The body 1 can be excavated. Further, generation of noise, vibration, and dust can be suppressed.
[0019]
If the height or width of the cavity 2 formed in the concrete body 1 is larger than 5 m, it is considered that the concrete block 6 cannot be cut out at once. In such a case, a single hole 5 is provided in the face 3 at intervals of 1 to 2 m in the vertical and horizontal directions, and the above-described cutting operation is performed a plurality of times so that a concrete block of a predetermined size can be cut out. What should I do?
[0020]
Next, a second concrete excavation method will be described with reference to FIG.
In FIG. 2, a continuous hole 4 is provided in a face 3 of a cavity 2 formed by demolishing a part of a concrete body 1 in the same manner as in the first excavation method.
[0021]
Next, the guide pulley on which the wire 7 of the wire saw is hung is inserted all the way into the continuous hole 4 and is installed at the upper left end A and the lower left end B of the concrete block 6 to be excavated in the excavation direction front. Similarly, guide pulleys on which the wires 7 are hung are installed at the upper right end C and the lower right end D of the concrete block 6 to be excavated, respectively, at the rear in the excavation direction.
When the guide pulley is installed as described above, the wire 7 is installed to be stretched between the guide pulleys installed in C, A, B, and D.
[0022]
Next, the concrete block 6 to be excavated is cut on a plane including C, A, B, and D by running the wire 7. At this time, the guide pulleys provided on A and B are appropriately moved so that the wire 7 moves on a plane including C, A, B and D. Further, the tension of the wire 7 is adjusted so as to be kept constant.
[0023]
The cut wedge-shaped concrete block 6 can be removed from the inside of the cavity 2 by a construction machine in the same manner as in the first excavation method. The remaining wedge-shaped portion of the concrete block 6 to be excavated can be cut out and removed in the same manner as in the first excavation method. The above operation is repeated to form the cavity 2 reaching the wall surface on the opposite side of the concrete body 1.
[0024]
According to the second excavation method, even when the concrete mass 6 to be excavated in the cavity 2 cannot be cut out at one time, the concrete mass 6 can be cut out in a wedge shape with a wire saw, thereby reducing the number of steps using a hydraulic jack. Can be.
[0025]
In the above embodiment, the concrete block 6 is cut out by using the hydraulic jack. However, the present invention is not limited to this. The concrete block 6 is formed by using a static crush material instead of the hydraulic jack. May be cut out. In addition, it goes without saying that the method of cutting out the concrete block 6 with a wire saw can be appropriately changed.
[0026]
【The invention's effect】
According to the invention described in claim 1, according to the invention described in claim 1, a U-shaped continuous hole formed by core boring, a crack formed by a hydraulic jack in a single hole between both ends of the U-shape, and a continuous hole are formed. Since the concrete block can be cut out in a block shape by the crack including the bottom of the hole, the concrete body can be efficiently excavated without trouble of crushing the concrete block. Further, generation of noise, vibration, and dust can be suppressed.
[0027]
According to the second aspect of the present invention, it is possible to cut out a concrete block into a wedge shape from a U-shaped continuous hole formed by core boring using a wire saw.
[Brief description of the drawings]
FIG. 1 is a view showing an example of a form of a cavity provided in a concrete body 1 by a concrete excavation method of the present invention, wherein (a) is a horizontal sectional view and (b) is a front view.
FIGS. 2A and 2B are diagrams showing another example of a cavity provided in the concrete body 1 by the concrete excavation method of the present invention, wherein FIG. 2A is a horizontal sectional view and FIG. 2B is a front view.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Concrete body 2 Cavity 3 Face 4 Continuous hole 5 Single hole 6 Concrete block 7 Wire

Claims (2)

A first step of drilling a continuous hole in a U shape by core boring on a face of a concrete body,
A second step of drilling a single hole between the U-shaped ends of the continuous hole,
Insert a hydraulic jack into the single hole to form a crack that connects between the U-shaped ends and form a crack including the bottom of the continuous hole, and remove the concrete mass surrounded by the continuous hole and the two cracks. A method for excavating a concrete body, comprising a third step of cutting out. A first step of drilling a continuous hole in a U shape by core boring on a face of a concrete body,
A second step of inserting a wire saw into the bottom of the continuous hole, and cutting the concrete block surrounded by the U-shape into a wedge shape by the wire saw.

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