JPH086299B2 - Opening method for concrete wall - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for opening a concrete wall.

<< Prior Art >> As is well known, in reservoirs such as dams, the inflow of running water causes sediment to gradually accumulate, resulting in a decrease in the storage capacity.

As a method for removing the sediment thus deposited, it has been considered to form an opening in the wall of the reservoir and remove the deposited sediment from this opening.

In addition to this, for example, when an intake channel is newly installed, it is necessary to form an opening in the wall body.In such a case, the wall body usually has a concrete structure having a thickness of about 10 m. It has been adopted and it is quite difficult to form an opening in the wall.

Therefore, Japanese Patent Laid-Open No. 63-60707 proposes a method for forming an opening in a thick concrete wall.

In the method disclosed in this publication, a through hole is formed in a corner portion of a concrete wall body where an opening is to be formed, a cutting wire is inserted into an adjacent through hole, and a cutting line is formed between the through holes. This is a method in which the openings are planned to be separated into columns, and the columnar separators separated in this way are then crushed and removed.By this method, it is possible to form openings in conventional thick concrete wall bodies. Although it was difficult or impossible, it is said that the opening can be formed safely and accurately, but in particular, when removing the columnar separator at the separated opening planned location, the technical problem described below occurs. there were.

<< Problems to be Solved by the Invention >> That is, in the opening method of the above publication, it is explained that the columnar separator separated from the concrete wall by wire sawing is sequentially crushed by explosives or a crusher. If such a crushing method is adopted, it is necessary to remove the wire sawing machine used to form the columnar separator and install the crusher, which complicates the process and extends the construction period.

In addition, the crushing method using explosives may damage parts other than the columnar separator.

The present invention has been made in view of such conventional problems, and an object thereof is to avoid the complication of the process and the extension of the construction period, and at the same time, concrete other than the opening forming portion. An object of the present invention is to provide a method for opening a concrete wall body that does not damage the wall body.

<< Means for Solving the Problem >> In order to achieve the above object, the present invention provides a step of forming through holes at intervals along the outer periphery of a portion where an opening is to be formed in a concrete wall body, and the adjacent through holes. A step of inserting a cutting wire between the holes to sequentially form cutting lines between the through holes, and separating the portion where the opening is to be formed from the concrete wall body to form a columnar separator. It is characterized in that it comprises a step of pulling out the body, and a step of winding the cutting wire around the outer periphery of the pulled-out columnar separating body and cutting and removing a part thereof.

<< Advantageous Effects of the Invention >> According to the opening method for the concrete wall body having the above-described structure, the cutting wire used for forming the columnar body is wound around the outer periphery of the columnar body separated from the concrete wall body. Since a part of it is cut and removed, troublesome removal work and installation of a crusher are unnecessary, and it is possible to simplify the process and shorten the construction period.

Embodiment Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 to 3 show an embodiment of an opening method for a concrete wall according to the present invention.

The opening method shown in the figure illustrates the case where the present invention is applied when forming an opening in a dam body of a reinforced concrete dam.

The opening method is, as shown in FIG. 1, a step of forming through holes 12 at intervals along the outer periphery of the portion where the openings are to be formed in the concrete wall body 10, and a cutting wire 14 is provided between the adjacent through holes 12. A step of inserting and sequentially forming a cutting line between the through holes 12 to separate the portion where the opening is to be formed from the concrete wall body to form a columnar separator 16, the columnar shown in FIG. It comprises a step of pulling out the separating body 16, and a step of winding the cutting wire 14 around the outer circumference of the pulled out columnar separating body 16 shown in FIG. 3 and cutting and removing a part thereof.

Explaining each of the above steps in detail, in the step, the work scaffold 18 is installed below the place where the opening is to be formed.
Through holes 12 are formed by using a punching machine or the like.

In this embodiment, since the rectangular opening is formed, the first
As shown in Figure (B), 4 along the outer circumference of the planned opening
Through holes 12 are provided in each of the two corners.

In the process, the concrete cutting machine 20 is installed on the work scaffold 18, and the cutting wire 14 is inserted between the adjacent through holes 12.

The cutting wire 14 used here is a so-called diamond wire having beads to which diamond powder is fixed, and the cutting wire 14 is inserted between the pair of through holes 12 and the concrete cutting machine 20. Is wound endlessly between the drive pulley 20a and the four guide pulleys 20b to 20e.

Then, between the pair of guide pulleys 20c, 20e on the lower stage side, a weight 20f that absorbs the tarumi generated along with the cutting of the wall body 10 and constantly applies a predetermined tension to the cutting wire 14 is provided via the pulley 20g. It has been suspended.

The reason for using such a weight 20f is to make the installation area of the concrete cutting machine 20 as small as possible in addition to the above.

When the concrete cutting machine 20 is installed and the drive pulley 20a is rotationally driven as described above, a cutting line is formed between the through holes 12 through which the cutting wire 14 is inserted.

In this case, the order of forming the cutting lines is, for example, the first
As shown in FIG. (B), the through holes are formed in the order of I to IV.
When the cutting line is formed on all of the spaces between the squares 12, a square columnar separator 16 separated from the wall 10 is formed at the planned opening.

In the process, a plurality of jacks 22 are provided around the columnar separator 16.
Is installed, the anchor material 24 is driven into one end of the columnar separating body 16, the anchor material 24 and the jack 22 are connected, and the jack
By driving the columnar separator 16 by driving 22 and one end thereof is pulled out by a predetermined length,
The withdrawal work is temporarily stopped.

In addition, in this process, although not shown, a workbench
The concrete cutting machine 20 is installed on the above 18.

In the step, the cutting wire 14 is wound around the outer periphery of the pulled-out portion of the columnar separator 16, and the drive pulley 20a is rotated while applying tension by the weight 20f in the same manner as in the step, and the one of the columnar separator 16 is rotated. The part is cut and removed.

At this time, a crane 26 is installed at the top of the concrete wall 10 to receive the removed portion.
A suspension wire 28 of 26 is joined to the part to be removed.

Then, when the portion cut by the cutting wire 14 is removed, the steps and steps are repeated again, and by performing this operation a plurality of times, when all of the columnar separators 16 are removed, the wall body 10 is removed. A rectangular opening is formed.

Now, when the opening is formed by the steps as described above, on the outer periphery of the columnar separating body 16 separated from the concrete wall body 10,
Since the cutting wire 14 used for forming the columnar separator 16 is wound and a part thereof is cut and removed, troublesome removal work of the cutting machine 20 and installation of a crusher are unnecessary, and It is possible to simplify and shorten the process.

In addition, it does not affect other parts of the wall body 10 unlike the crushing by explosives.

Furthermore, if the weight 20f is used as a means for applying tension to the cutting wire 14, the installation area of the cutting machine 20 is also reduced.

[Brief description of drawings]

1 to 3 are explanatory views showing an embodiment of an opening method for a concrete wall according to the present invention in the order of steps. 10 …… Concrete wall 12 …… Through hole 14 …… Cutting wire 16 …… Columnar separator

Claims (1)

[Claims] 1. A step of forming through holes at intervals along the outer periphery of a portion where openings are to be formed in a concrete wall body, a cutting wire is inserted between adjacent through holes, and between the through holes. A step of sequentially forming cutting lines to form a columnar separator by separating the opening formation planned portion from the concrete wall body, a step of pulling out the columnar separator, the outer periphery of the columnar separator pulled out. An opening method for a concrete wall body, which comprises a step of winding a cutting wire and cutting a part thereof to remove it.