JP2000314123A - Method for forming opening in reinforced concrete wall - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for forming openings economically. SOLUTION: When forming openings, longitudinal sections are cut by wire saws at the right and left of the scheduled opening positions thereby creating the longitudinal section lines. Next, core boring holes 20 are formed in the places for scheduled openings subdivided by the longitudinal section lines. The core boreholes 20 have both horizontal core boreholes 20a and vertical core boreholes 20b. Next, within the first step horizontal core boreholes 20a, cylinder heads 24 are respectively inserted and installed, these are enlarged and operated at the same time and the lateral cutting line B1 is formed by its breaking. Next, a cylinder head 24 is inserted and installed in a vertical core borehole 20b provided at the upper portion side from the first step horizontal borehole 20a, and enlarging operation is performed and longitudinal cutting line C1 is formed. When the longitudinal cutting line C1 is formed, the portion at the upper portion side from the first step horizontal borehole 20a is fully separated at the portion of the longitudinal cutting line C1 and divided into a block 34. The divided block 34 is sequentially removed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for forming an opening in a reinforced concrete wall.

[0002]

2. Description of the Related Art As a method of forming an opening for a fishway or the like in a concrete wall such as a dam embankment, there is, for example, an opening method disclosed in Japanese Patent Application Laid-Open No. 7-173820. The opening method proposed in this publication is a method of forming an opening in a reinforced concrete dam embankment having a thickness of 1 m or more, and is provided at each corner of an opening forming area of the reinforced concrete embankment. A column for forming an opening by drilling a cable through hole in the thickness direction with a core drill, winding a wire saw between adjacent cable through holes, and running the wire saw in a predetermined tension state in the normal direction. Is cut off from the embankment body, and then the columnar body is crushed and removed.

According to the opening method proposed in this publication, an opening having a required size can be accurately formed without causing undesired destruction to the surroundings. However, such a conventional opening method has a problem described below.

[0004]

That is, in the opening method proposed in the above-mentioned open method, four rounds of a columnar body for forming an opening are cut by a wire saw.
A wire saw is made by loosely fitting a large number of diamond beads at predetermined intervals on a wire cable, and cuts the diamond beads by frictionally running them on reinforced concrete.

[0005] When reinforced concrete is cut by the friction of such diamond beads, the cut surface becomes smooth, but the diamond beads are worn out with cutting and become unusable, and the wire saw using diamond beads is expensive. Therefore, there was a problem that the construction cost was extremely high.

In the opening method disclosed in the above publication, it is also proposed to employ a wire saw and cut it into blocks when crushing and removing the columnar body cut and separated by the wire saw. When such a method is adopted, high cost construction is required to remove the columnar portion to be discarded, and there is also a problem that the economy of the construction is deteriorated.

[0007] The present invention has been made in view of such a conventional problem, and an object of the present invention is to provide a method capable of forming an opening economically.

[0008]

In order to achieve the above object, the present invention relates to a method for forming an opening in a concrete wall such as a dam embankment, comprising the steps of: Forming a vertical section line separating both side surfaces of the opening, and forming a core boring hole penetrating the concrete wall in the opening defined by the vertical section line. The cylinder head of the hydraulic crusher is inserted and installed in the core boring hole, and the periphery of the core boring hole is crushed by the enlarging operation of the cylinder head, so that the inside of the opening sectioned by the vertical cross-sectional line is cut vertically. And forming a horizontal cutting line,
The method includes a step of dividing the concrete wall in the opening into blocks, and a step of sequentially removing the divided blocks. According to the method of forming an opening in a reinforced concrete wall configured in this manner, since cutting with a wire saw is performed only on the left and right vertical sections of the place where the opening is to be formed,
The construction cost is not so high. The vertical and horizontal cutting lines may be formed by forming the horizontal cutting line before the vertical cutting line. The horizontal cutting line is inserted into the plurality of core boring holes formed in a horizontal line, respectively, and the cylinder heads of the hydraulic crusher are inserted and installed, and the cylinder heads are simultaneously expanded and operated, and the left and right vertical sectional lines are formed. It can be formed so as to connect them. The vertical cutting line is formed in a state inclined at a predetermined angle so as to be oblique to the horizontal cutting line, and a part of the block is formed in a tapered shape or an inverted C shape, and a block having such a shape is formed. It can be lifted first and removed. The present invention also provides a method of forming an opening in a concrete wall such as a dam body,
A step of cutting the left and right vertical cross sections of the portion where the opening is to be formed with a wire saw to form vertical cross sectional lines separating both side surfaces of the opening, and forming a horizontal cutting line between the vertical cross sectional lines with a wire saw; Forming a core boring hole penetrating the concrete wall in the opening sectioned by the vertical section line, and inserting and installing a cylinder head of a hydraulic crusher in the core boring hole; Crushing the periphery of the core boring hole, forming a vertical cutting line in the opening sectioned by the vertical section line, and dividing the concrete wall in the opening into blocks, Sequentially removing the divided blocks.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. 1 to 4 show one embodiment of a method for forming an opening in a reinforced concrete wall according to the present invention.

[0010] The method of forming an opening shown in FIG. 1 exemplifies a case where the method is applied to forming an opening 12 for a fishway in an existing dam embankment 10 as a reinforced concrete wall. As shown in FIG. 1, the dam embankment body 10 shown in FIG. 1 has both side surfaces inclined so as to increase in width from the upper end side to the lower end side, and has a substantially trapezoidal longitudinal section. I have.

With respect to the dam embankment body 10 having such a shape,
The opening 12 is formed in a substantially concave shape so that the upper end thereof is opened so as to coincide with the upper end of the dam embankment body 10 and both side surfaces and the bottom surface are located inside the dam embankment body 10.

When forming such an opening 12,
First, as shown in FIG. 1, a step of forming a vertical section line 16 of the opening 12 by cutting the left and right vertical sections 14 of a portion where the opening 12 is to be formed with a wire saw is performed.

When forming the vertical section line 16, the dam embankment 10 is placed on both sides of the lower end of the place where the opening 12 is to be formed.
Are formed in a small-diameter boring hole 18 that penetrates in the horizontal direction. The small-diameter boring hole 18 may have a diameter through which a wire saw (not shown) can be inserted, for example, a diameter of about several tens mm.

When the small-diameter boring hole 18 is formed, a wire saw is inserted into the small-diameter boring hole 18, wound around the longitudinal section 14, and the wound wire saw is circulated and driven under a predetermined tension. Then, the dam embankment body 10 is cut in the vertical direction to form a vertical section line 16.

The longitudinal section line 16 formed in this manner is
Is maintained at an interval through which the wire saw is inserted. in this case,
The running direction of the wire saw is changed by a guide pulley installed at an appropriate location, and the wire saw is guided to the drive device side.

When the longitudinal section lines 16 on both sides are formed by the wire saw, the end face of the dam embankment body 10 along the section lines 16 becomes a smooth surface, so that the opening portion is not subjected to any finishing processing, and the opening portion is left as it is. Used as 12 sides.

After the vertical cutting line 16 is formed, a step of forming a core boring hole 20 penetrating through the dam embankment body 10 in the opening 12 defined by the vertical section line 16 is performed. The core boring hole 20 is for inserting the thin lid 24 of the hydraulic crusher 22 and has a diameter of, for example, 200 mmφ, and is formed by the core boring machine 23 as shown in FIG. You.

When the drilling of the core boring hole 20 is completed, the cylinder head 26 of the hydraulic crusher 24 is
Is inserted.

The hydraulic crusher 22 used in the present embodiment includes a hydraulic unit 28 mounted on a carriage 26, and the hydraulic unit 28 and the cylinder head 24 are connected to a hydraulic hose 30.
And the connector 32.

Although only three cylinder heads 24 are shown in FIG. 1 in this hydraulic unit 28, connection driving of a maximum of four cylinder heads 24 is possible. FIG. 2 and FIG. 3 show details of the cylinder head 24 installed in the core boring hole 20.

The cylinder head 24 shown in these figures
Is a cylinder body 24a to which the hydraulic hose 30 is connected.
And an expansion plate 24b composed of a curved curved plate and a telescopic piston 24c.

As shown in FIG. 3, the state of insertion and installation of the cylinder head 24 is centered on the extension of the anticipated cutting line A ′ due to breakage formed around the core boring hole 20.
The cylinder body 2 is provided on one inner surface side of the core boring hole 20.
4a is arranged so that the curved expansion plate 24b is positioned on the other inner surface side.

[0023] Curved expansion plate 24b
Has an outer surface abutting against an inner surface of the core boring hole 20 and one end of an extendable piston 24c facing the inner surface thereof.
a.

When high-pressure oil is sent from the hydraulic unit 28 to the thus configured cylinder head 24 via the hydraulic hose 30, the telescopic piston 24c extends, and the curved expansion plate 24b is inserted into the core boring hole 2b.
As shown in FIG. 3, the core boring hole 20 is strongly pressed against the inner surface of the core boring hole 0 to perform such an enlarging operation.
Is destroyed, and a cutting line A is formed.

Here, in the case of the present embodiment, the core boring hole 20 is formed so as to penetrate the dam embankment 10 in the horizontal direction, and is positioned on a horizontal line substantially parallel to the upper end of the dam embankment 10. A plurality of horizontal core boring holes 20a provided in a plurality of steps at intervals of a plurality of vertical core boring holes 20b provided at a predetermined interval on a vertical line substantially orthogonal to the upper end of the dam embankment 10. It is composed of

When such a core boring hole 20 is formed, first, as shown in FIG. 1, a cylinder is inserted into a first-stage horizontal core boring hole 20a located on the upper end side of the dam embankment body 10. The heads 24 are respectively inserted and installed.

In this case, if one cylinder head 24 is installed in one core boring hole 20a, the installation position of the cylinder head 24 is approximately at the center in the longitudinal direction of the core boring hole 20a. Position.

When the cylinder heads 24 are inserted and installed in the horizontal core boring holes 20a, high-pressure oil is supplied to each of the cylinder heads 24 and they are simultaneously expanded.

When the cylinder head 24 is expanded,
Expansion plate 24 of each cylinder head 24
At b, the side surface of the horizontal core boring hole 20a is pressed outward.

The pressing force at this time is such that horizontal cross-section lines 16 are formed on both sides of the place where the opening 12 of the dam embankment 10 is to be formed, and the upper end of the dam embankment 10 is open. Since the lower side of the hole 20a is integrated with the dam embankment body 10, the pressing force acts only in the direction in which the upper part of the horizontal core boring hole 20a is lifted up.

[0031] When the pressing force in this direction acts, around the horizontal core borehole 20a, the transverse cutting line B ₁ such as to connect between the boreholes 20a adjacent in the horizontal direction is formed by the fracture.

[0032] Such transverse cutting line B ₁ represents, extends so as to connect between longitudinal section line 16 on both sides to be formed location of the opening 12, by the formation of the transverse cut line B _1, first stage The upper part from the horizontal boring hole 20a is the dam embankment 1
Separated from zero.

[0033] When the transverse cut line B ₁ in this manner is formed, then a vertical core borehole is provided in the portion of the top side from the first-stage horizontal borehole 20a 20b
The cylinder head 24 is inserted and installed therein, and the enlarging operation is performed.

[0034] When the expanding operation of the cylinder head 24 in the vertical core borehole 20b, as shown in FIG. 4, perpendicular to the horizontal cut line B _1, the vertical cutting lines C ₁ to reach the upper end of the dam 10 Is formed.

[0035] When forming such a vertical cutting line C _1, the upper side of the portion from the first-stage horizontal borehole 20a is
It is completely separated from the dam embankment body 10 at the portion of the vertical cutting line C ₁ and divided into blocks 34.

Such a block 34 includes a vertical cutting line C _1.
The blocks 34 are sequentially removed with the use of a crane or the like in the order of occurrence. When the upper part of the first-stage horizontal core boring hole 20a is divided into blocks 34 and all are removed, the cylinder head 24 is inserted and installed in the second-stage horizontal core boring hole 20a. the same operation as described above, after forming a horizontal cut line B ₂ of the second stage, the vertical borehole 20
b, the cylinder head 24 is inserted and installed, and the vertical cutting line C
₂ are sequentially formed, and the divided block 34 is removed.

By repeating such operations a plurality of times, an opening 12 having a predetermined shape is formed in the dam embankment body 10. According to the method of forming an opening in a reinforced concrete wall configured as described above, the cutting by the wire saw is performed only on the left and right vertical cross sections of the portion where the opening 12 is to be formed, so that the construction cost is not so high.

That is, in the case of this embodiment, the opening 12
Is high, and it is difficult to perform post-processing of the side surface after forming the opening portion 12. Therefore, this portion is cut with a wire saw that can obtain a smooth surface that does not require post-processing. The portion employs a hydraulic crusher 22 that can be constructed at a relatively low cost, including an internal block, so as to reduce the construction cost.

FIG. 5 shows another embodiment of a method of forming an opening according to the present invention. The same or corresponding parts as those of the above embodiment are denoted by the same reference numerals, and the description thereof will be omitted. Hereinafter, only the characteristic points will be described.

The method shown in FIG. 1 is adopted when the thickness of the concrete wall forming the opening 12 is relatively large. FIG. 5 shows that the hydraulic crusher 22 is installed in the core boring hole 20. A state where the thin head 24 is inserted and installed is shown.

In the figure, two cylinder heads 2
4 are inserted and installed at a predetermined interval in one core boring hole 20. The hydraulic hose 30 of the lower cylinder head 24 extends upward from a gap between the upper cylinder head 24.

When a plurality of cylinder heads 24 are inserted and installed in one core boring hole 20 in this way and simultaneously expanded, the pressing force on the core boring holes 20 increases according to the number of installations. Even when the wall thickness is large, the vertical and horizontal cutting lines can be formed relatively easily.

FIG. 6 shows still another embodiment of the method of forming an opening according to the present invention. The same reference numerals are given to the same or corresponding parts as in the above embodiment, and the description thereof will be omitted. In addition, only the characteristic points will be described below.

In the method of forming the opening shown in FIG. 4, similarly to the process shown in FIG. 1, first, the left and right vertical sections 14 at the place where the opening 12 is to be formed are cut by a wire saw, and both sides of the opening are formed. A longitudinal section line 16 separating the surfaces is formed.

Next, the opening 1 defined by the vertical section line 16
2, a vertical core boring hole 20b 'penetrating the concrete wall is formed, and the cylinder head 24 of the hydraulic crusher 22 is inserted and installed in each vertical core boring hole 20b'. The area around the boring hole 20b 'is crushed and
A vertical cutting line C is formed in the opening 12 defined by the above, and the concrete wall in the opening 12 is connected to the blocks 34a, 3b.
4b.

At this time, in this embodiment, the horizontal cutting line B in the opening 12 to be formed is formed by cutting with a wire saw like the vertical section line 16. The horizontal cutting line B may be formed to have its entire length before the vertical cutting line C is formed, or the formation of the horizontal cutting line B may be performed in a simultaneous progressive manner. It may be.

The blocks 34a and 34b are not the same in shape, but are formed by dividing the blocks 34a and 34b every other in the horizontal direction.

That is, one of the blocks 34a has an area on the upper end side larger than the area on the lower end side, and is formed in a tapered or inverted C-shape.
4b, the area on the upper end side is smaller than the area on the lower end side, and is formed in a divergent shape or a C-shape.

In order to divide into such blocks 34a and 34b, it is necessary to form the vertical cutting line C at a predetermined angle, for example, several degrees from the vertical so that the vertical cutting line C is oblique to the horizontal cutting line B. There is.

When the vertical cutting line C is inclined, a pair of vertical core boring holes 20b 'are formed at predetermined intervals on a vertical cutting line C' inclined at a predetermined angle. The cylinder head 24 of the hydraulic crusher 22 is inserted and installed in each of the vertical core boring holes 20b ′, and the cylinder head 24 is expanded to operate the vertical core boring holes 2b.
The vertical cutting line C may be formed by crushing the periphery of 0b '.

Block 3 divided by forming vertical cutting line C
When removing 4a and 34b, first, a block 34a formed in a tapered or inverted C shape is suspended from above and removed.

In this embodiment, since the cutting area of the wire saw is larger than that of the above embodiment, the economy is slightly lowered. However, the tapered or inverted C-shaped block 34a is used first. , The competition on the side surface on which the vertical cutting line C is formed is eliminated, and the block 34a can be easily pulled up, so that the workability is improved.

That is, as in the present embodiment, when a series of walls are formed into blocks, the blocks to be removed first, for example, if both vertical cutting lines C are formed vertically, the blocks compete on both sides, and In some cases, it is difficult to pull up the wire, and particularly when the vertical cutting line C is formed by crushing as in the present embodiment, the cut surface is not smooth like a wire saw, and irregularities are formed, so the tendency becomes remarkable. .

However, such a problem can be avoided by arranging the block 34a formed in a tapered or inverted C-shape as in this embodiment and pulling up this portion first. be able to.

When one tapered or inverted C-shaped block 34a is removed, one side is released by removing the block 34a when lifting the side block. You don't have to think about competing.

Therefore, the tapered or inverted C-shape blocks 34a that can provide such an effect need only be provided at one place in one stage, and thus they need not necessarily be arranged alternately as shown in FIG.

The advantage of forming the horizontal cutting line B with a wire saw is effectively exhibited under the following working conditions. That is, for example, when a vertical joint surface, such as that indicated by reference numeral K in FIG. 6, is present on the dam squab 10, the joint surface K becomes substantially orthogonal to the transverse cutting line B. .

With such a joint surface K, when the hydraulic crusher 22 attempts to form the transverse cutting line B, the crushing force of the crusher 22 is divided at the joint surface K, and the rear side is cut. The lines cannot be continuous.

However, when the horizontal cutting line B is formed by the wire saw, such inconvenience is eliminated. In addition,
The joint surface of the dam corpse 10 also exists in the vertical direction,
Since the vertical cutting line C is relatively short, even if it exists, there is almost no problem.

In the above embodiment, the dam embankment 10 is exemplified as the reinforced concrete wall forming the opening 12; however, the present invention is not limited to this.

[0061]

As described in detail above, according to the method of forming an opening in a reinforced concrete wall according to the present invention, an opening can be formed economically.

[Brief description of the drawings]

FIG. 1 is an explanatory view of an initial step showing one embodiment of a method for forming an opening in a reinforced concrete wall according to the present invention.

FIGS. 2A and 2B are a top view and a side view illustrating an installation state before the operation of the cylinder head when a cutting line is formed by the cylinder head of the hydraulic crusher by the method of FIG.

3A and 3B are a top view and a side view after the cylinder head is operated from the installation state of FIG. 2;

FIG. 4 is an explanatory view of a step performed subsequent to FIG. 1;

FIG. 5 is an explanatory view of an installation state of a cylinder head showing another embodiment of a method for forming an opening in a reinforced concrete wall according to the present invention.

FIG. 6 is an explanatory view showing still another embodiment of the method for forming an opening in a reinforced concrete wall according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Dam embankment body 12 Opening 14 Longitudinal section 16 Longitudinal section line 20 Core boring hole 20a Horizontal core boring hole 20b Vertical core boring hole 22 Hydraulic crusher 24 Cylinder head

Claims (5)

[Claims] 1. A method of forming an opening in a concrete wall such as a dam embankment, wherein a left and right vertical cross section of a portion where the opening is to be formed is cut by a wire saw to separate both side surfaces of the opening. Forming a surface line; forming a core boring hole penetrating the concrete wall in the opening defined by the longitudinal section line; inserting and installing a cylinder head of a hydraulic crusher in the core boring hole. Then, by the expanding operation of the cylinder head, the periphery of the core boring hole is crushed to form vertical and horizontal cutting lines in the opening sectioned by the vertical sectional line, and the concrete wall in the opening section is cut. A method of forming an opening in a reinforced concrete wall, comprising a step of dividing into blocks and a step of sequentially removing the divided blocks. 2. The method for forming an opening in a reinforced concrete wall according to claim 1, wherein the vertical and horizontal cutting lines form the horizontal cutting line before the vertical cutting line. 3. The horizontal cutting line is formed by inserting and installing a cylinder head of the hydraulic crusher into a plurality of core boring holes formed in a horizontal line, and simultaneously expanding and operating the cylinder head. 3. The method for forming an opening in a reinforced concrete wall according to claim 2, wherein the opening is formed so as to connect the vertical section lines. 4. The vertical cutting line is formed to be inclined at a predetermined angle so as to be oblique to the horizontal cutting line, and a part of the block is formed in a tapered shape or an inverted C shape. 2. The method as claimed in claim 1, wherein the blocks having different shapes are first lifted up and removed. 5. A method for forming an opening in a concrete wall such as a dam embankment, wherein a left and right vertical cross section of a portion where the opening is to be formed is cut by a wire saw to separate both side surfaces of the opening. Forming a face line; forming a horizontal cutting line between the vertical section lines with a wire saw; and forming a core boring hole penetrating the concrete wall in the opening defined by the vertical section line. The cylinder head of the hydraulic crusher is inserted and installed in the core boring hole, and the periphery of the core boring hole is crushed by the enlarging operation of the cylinder head, so that the cylinder head is vertically inserted into the opening section defined by the vertical sectional line. Forming a cutting line,
A method of forming an opening in a reinforced concrete wall, comprising: a step of dividing a concrete wall in the opening into blocks; and a step of sequentially removing the divided block.