JP2004225318A - Anchorage device and anchorage method for removal type anchor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an anchorage device and an anchorage method for a removal type anchor, in which a machine is not used for extracting a steel wire and by which the steel wire can be extracted by human power and a peripheral environment is not contaminated. <P>SOLUTION: The anchorage device has an anchorage external cylinder, in which a terminal on the underground side of the steel wire is housed, and grips the steel wire from a periphery by a gripping mechanism installed in the external cylinder. Gripping force by the gripping mechanism is released by working pressure force from the pit mouth side to the pit bottom side to the terminal of the steel wire in the case of a removal. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a fixing device and a fixing method for a removable anchor.
[0002]
[Prior art]
The removable anchor is an anchor that removes unnecessary anchor anchors and steel wires from the ground after the purpose of use of the anchor has been achieved.
For this reason, a conventional removable anchor is known in which a steel wire covered with a resin is folded and installed in a U-shape at the deepest portion in the ground, and at the time of removal, the steel wire is removed by pulling out one end of the steel wire. (For example, see Patent Document 1)
[0003]
[Patent Document 1]
JP-A-5-295729 (FIG. 1)
[0004]
[Problems to be solved by the present invention]
The above-mentioned conventional removable anchor has the following problems.
<B> Since the steel wire is bent into a U-shape in the drilled hole, a large deformation external force acts on the bent portion, and the strength is reduced.
<B> Since the steel wire is bent at a steep angle at the deepest portion, the bent portion has a large resistance and cannot be pulled out without applying a considerably large force.
<C> The machine cannot be pulled out unless a large force is applied, so a machine is required for drawing out. In order to pull out with a machine, a site on which the machine is to be installed and a site on which the machine is to be moved are required.
<D> Since a steel wire having a large diameter cannot be folded back into a U-shape, it is necessary to use many thin steel wires. For this reason, the diameter of the hole is increased, or a large number of holes are required, which increases the labor and cost of the hole.
<E> The steel wire is covered with a resin pipe so that it can be pulled out, and oil and fat are applied around the steel wire. Therefore, the drawn steel wire is covered with oil and fat, and the work place is easily stained with oil and fat. In addition, the steel wire collected by drawing is covered with oils and fats, so it cannot be reused and also requires special consideration for disposal.
<F> Even after the steel wire is removed, resin pipes and a large amount of oil and fat will remain in the ground. For this reason, oils and fats may ooze into the ground over many years, contaminating the ground and groundwater.
[0005]
[Object of the present invention]
The present invention has been made in order to solve the above-mentioned conventional problems, and does not use a machine for pulling out a steel wire, can be pulled out manually, and does not pollute the surrounding environment. It is an object of the present invention to provide a fixing device and a fixing method for a removable anchor.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the anchor of the removable anchor of the present invention is an anchor steel anchor for a steel wire to be inserted into a drilled hole, and a terminal on the underground side of the steel wire. With the fixing outer cylinder to be stored, the steel wire is gripped from the periphery by a gripping mechanism provided inside the outer cylinder, and by applying a pressing force from the hole opening side to the hole bottom side at the end of the steel wire, It is characterized by a fixing device of a removable anchor configured to release the gripping force by the gripping mechanism.
Further, the fixing method of the removable anchor according to the present invention is a fixing method of an anchor steel wire to be inserted into a drilled hole, comprising a fixing outer cylinder for accommodating a terminal on the underground side of the steel wire. With the gripping mechanism provided inside the cylinder, the steel wire is gripped from the surroundings, and the pressing force from the hole opening side to the hole bottom side is applied to the end of the steel wire to release the gripping force by the gripping mechanism. It is characterized by a method of fixing a removable anchor, which is performed in such a manner as to obtain the anchor.
[0007]
[Embodiment of the present invention]
Hereinafter, an embodiment of a fixing device for a removable anchor according to the present invention will be described with reference to the drawings.
[0008]
<A> Fixing outer cylinder.
The fixing device of the present invention is a fixing device that is inserted into a hole that has been drilled to fix the terminal of the anchor steel wire to the ground.
Further, there is provided a fixing outer cylinder 1 for accommodating a terminal on the underground side of the steel wire.
The outer cylinder 1 is a cylindrical body having one open side, and a gripping mechanism and an engagement mechanism are provided on an inner wall thereof.
Actually, the outer cylinder 1 is divided into a hole-side outer cylinder 1A arranged on the hole side and a hole-bottom side outer cylinder 1B arranged on the hole bottom side of the hole. Then, both outer cylinders are configured so that they can be divided and integrated with screws.
Therefore, the hole-side outer cylinder 1A is formed as a cylindrical shape with both ends opened, and the hole-bottom-side outer cylinder 1B is formed as a cup-shaped cylinder with one end closed.
[0009]
<B> Steel wire gripping mechanism.
A gripping mechanism is provided inside the hole side outer cylinder 1A, and the steel wire is gripped from the periphery by the gripping mechanism.
For example, a wedge mechanism is provided as a gripping mechanism.
For that purpose, the inner wall of the hole side outer cylinder 1A forms a wedge base 2B whose inner diameter increases toward the hole bottom side of the hole.
Therefore, the inner surface of the hole side outer cylinder 1A is formed as a trumpet-shaped slope whose inner diameter increases toward the hole bottom side of the hole.
On the other hand, inside the hole side outer cylinder 1A, a wedge piece 2A obtained by dividing the cylinder into a plurality of pieces is stored in parallel with the center line thereof.
This wedge piece 2A is an arc-shaped plate body, the inner surface of which forms a curved surface parallel to the central axis of the cylinder, and the outer surface of which is formed in a shape whose outer diameter decreases toward the hole opening side. I do.
The outer surface of the wedge piece 2A and the slope of the wedge base 2B are formed at an angle such that they contact each other as a surface.
Therefore, when the plurality of wedge pieces 2A are located on the bottom side of the hole, the interval between the wedge pieces 2A is widened, and when the wedge pieces 2A are pushed to the hole mouth side, the wedge pieces 2A are inclined on the slope of the wedge stand 2B. , The distance between them is reduced while sliding, so that the inner surface finally forms almost one cylinder.
[0010]
<C> Support member.
The support member 3 that supports the wedge pieces 2A at the bottom of the hole is housed inside the bottom outer cylinder 1B.
The support member 3 is a columnar body slidable along the inner wall of the hole bottom side outer cylinder 1 </ b> B. The support member 3 is given a pushing force toward the hole by a pushing spring 31.
Further, as shown in FIG. 4, a wedge piece locking groove 32 is formed in the support member 3 on the opening side.
On the other hand, a locking shelf 33 is formed on the bottom side of the hole of the wedge piece 2A, and the locking shelf 33 is configured to be able to engage with the locking groove 32 of the support member 3.
[0011]
<D> Engaging mechanism.
The support member 3 is engageable with the hole bottom side outer cylinder 1B via an engagement mechanism.
The engaging mechanism is constituted by, for example, an engaging pin 34 which gives elasticity and protrudes from the support member 3 toward the inner wall of the outer cylinder 1B on the hole bottom side.
For this purpose, a storage hole facing the inner wall is formed in the support member 3, and the pin 34 and the spring are stored in the storage hole.
On the other hand, a pin engaging groove 35 is formed in the inner wall of the outer cylinder 1B on the hole bottom side.
Therefore, when the support member 3 pushed to the hole opening side by the pushing spring 31 moves to the hole bottom side by a certain distance, the pin 34 falls into the pin engagement groove 35 of the inner wall. As a result, the support member 3 is prevented from being pushed back toward the opening.
Note that the engagement mechanism is not limited to the combination of the pin 34 and the pin engagement groove 35, but may be one such as dropping the spring plate into the groove or projecting the engagement member from the outer cylinder side to the support member 3. Known non-return mechanisms that allow sliding in the direction but prevent retraction can be widely employed.
[0012]
<E> Configuration at the time of fixing. (Fig. 2)
The hole-side outer cylinder 1A and the hole-bottom-side outer cylinder 1B are separated, and the underground end of the steel wire 4 is passed through the inside of the cylindrical hole-side outer cylinder 1A and into the hole-bottom-side outer cylinder 1B. insert.
The periphery is covered with a synthetic resin coating 41 so that the steel wire 4 is not fixed by the mortar injected into the periphery, and the steel wire 4 is exposed only at the terminal portion. However, since the steel wire 4 has almost no resistance during drawing as described later, it is not necessary to interpose oil or fat between the steel wire 4 and the surrounding coating 41 as in the conventional case.
The end of the steel wire 4 exposed in this way is inserted to a position where it comes into contact with the support member 3 through a space surrounded by the wedge piece 2A group.
Next, when the outer cylinder is rotated via a screw in order to integrate the two outer cylinders, the wedge base 2B moves to the hole bottom side, and the wedge pieces 2A group that has been divided and arranged are squeezed. The steel wire 4 is clamped and fixed from the periphery by the wedge pieces 2A.
A separately prepared load-bearing body is attached to the steel wire 4 to which the outer cylinder is fixed, inserted into the drilled hole, mortar is injected and fixed, and then a tensile force is applied to the steel wire 4 from outside the hole by a jack. For this anchor installation step, various conventionally known methods can be adopted.
[0013]
<F> When the steel wire 4 is removed. (Fig. 3)
When the use as the anchor is completed, the steel wire 4 is removed from the ground.
For this purpose, the exposed portion of the steel wire 4 outside the hole is cut.
Then, the tension of the steel wire 4 which has been applied up to that time is released, and the force acts as a force for pushing the support member 3 from the hole opening side to the hole bottom side through the end of the steel wire 4 on the hole bottom side.
When the push-back force to the hole bottom side via the steel wire 4 is insufficient, the same push-back force can be obtained by hitting the outer end of the steel wire 4 with a hammer.
If the elasticity of the push-out spring 31 pressing the support member 3 is set to be smaller than this push-back force, the support member 3 slides toward the hole bottom.
Then, the support member 3 is engaged with the outer cylinder by the engagement mechanism, and it is impossible to return to the previous position.
By the sliding of the support member 3, the wedge piece 2A attached thereto also slides to the hole bottom side.
Therefore, the interval between the wedge piece 2A and the wedge base 2B increases, the gripping force holding the steel wire 4 disappears in the wedge side group, and the steel wire 4 is released from fixing.
When the gripping force at the end on the bottom side of the hole is released, the external force acting on the steel wire 4 is eliminated, so that the steel wire 4 can be easily pulled out from the outside of the hole by human power.
Thus, the removal of the steel wire 4 from the ground is completed.
[0014]
[Effects of the present invention]
Since the fixing device and the fixing method of the removable anchor according to the present invention are as described above, the following effects can be obtained.
<A> The steel wire is not bent in a U-shape in a narrow hole as in the prior art, and since the steel wire is used in a straight state, the strength does not decrease.
<B> Since the steel wire is used in a straight state, there is no large resistance portion unlike the conventional U-shaped anchor. Therefore, even a long steel wire can be easily pulled out manually.
<C> Since a large force is not required for pulling out, there is no need for a machine for pulling out, and there is no need for land for installing the machine or for moving the machine. It can be carried out.
<D> Although a thick steel wire cannot be folded back into a U-shape with a small diameter, such a need is not required in the present invention, so a thick steel wire can be used as an anchor. For this reason, it is not necessary to form a large number of holes, and the labor and cost of the holes can be greatly reduced.
<E> Since the end of the steel wire has no resistance, there is no need to cover the steel wire with a resin interposed therebetween. For this reason, since no oil or fat adheres to the drawn steel wire, the working environment is good, and the drawn and collected steel wire can be reused.
<F> Since no oil or fat is used originally, no oil or fat remains in the ground, and there is no possibility of contaminating the ground or groundwater.
[Brief description of the drawings]
FIG. 1 is an explanatory view of a state in which a part of an embodiment of a gripping mechanism and an engaging mechanism of a fixing tool of a removable anchor according to the present invention is partially cut off.
FIG. 2 is a cross-sectional view of a state where a steel wire is gripped by a fixing device.
FIG. 3 is an explanatory view of a state where the fixing tool has released the gripping of the steel wire.
FIG. 4 is an explanatory view of an embodiment of a support member and wedge pieces.
FIG. 5 is an external view of a state in which a steel wire is attached to the fixing device.

Claims (3)

An anchor for anchor steel wire to be inserted into the bored hole,
Equipped with a fuser outer cylinder that stores the terminal on the underground side of the steel wire,
By the gripping mechanism provided inside the outer cylinder, the steel wire is gripped from around,
By applying a pressing force from the hole mouth side to the hole bottom side on the end of the steel wire,
It is configured to release the gripping force by the gripping mechanism,
Removable anchor anchor. An anchor for anchor steel wire to be inserted into the bored hole,
Equipped with a fuser outer cylinder that stores the terminal on the underground side of the steel wire,
On the inner surface of this outer cylinder,
An engaging part on the bottom side of the hole,
On the hole mouth side, a wedge base whose inner diameter increases toward the hole bottom side of the hole is formed,
Inside the outer cylinder,
A wedge piece divided into a plurality of pieces and a supporting member for supporting the wedge piece group at the bottom of the hole are stored,
The support member is given a pushing force to the hole side,
When the support member is pushed back to the hole bottom side of the hole, the engaging portion on the inner surface of the outer cylinder and the support member are configured to be engaged.
Removable anchor anchor. A method of anchoring an anchor steel wire to be inserted into a bored hole,
Equipped with a fuser outer cylinder that stores the terminal on the underground side of the steel wire,
With the gripping mechanism provided inside the outer cylinder, while holding the steel wire from the surroundings,
By applying a pressing force from the hole mouth side to the hole bottom side on the end of the steel wire,
Performed so that the gripping force by the gripping mechanism can be released.
How to fix a removable anchor.

Images