JP6889877B2 - Anchor fixing clip and anchor fixing method - Google Patents

Description

In the present invention, an anchor (a metal rod-shaped member embedded in the skeleton for the purpose of fixing various elements to the concrete skeleton or for the purpose of reinforcing the skeleton itself) is fixed in a hole formed in the skeleton. The present invention relates to a clip used for fixing an anchor in a drilling hole using the clip.

In a concrete structure, holes are formed in the floor, walls, ceiling, etc. of the skeleton, and anchors (shear reinforcing bars) are inserted into these holes and backfilled with grout or the like. Work to increase the shear strength of the skeleton (shear reinforcement work) is being carried out.

FIG. 5 is a diagram showing a general construction example (construction procedure) of shear reinforcement work carried out on the ceiling portion of the skeleton. First, as shown in FIG. 5 (1), cutting is performed from the ceiling surface 22 of the skeleton 21 upward (inside the skeleton 21) using a core bit or the like to form an upward drilling hole 23. Then, the drilling 23 is subjected to a roughening treatment to make the inner wall of the drilling 23 a rough surface. Next, a nozzle (not shown) of the grout injection hose is inserted into the hole 23, and as shown in FIG. 5 (2), from the hole bottom 23a (the innermost part of the hole 23) to the opening 23b side. Grout 24 is injected sequentially.

Subsequently, as shown in FIG. 5 (3), the shear reinforcing reinforcing bar 11 is inserted upward from the opening 23b into the drilled hole 23 before the injected grout 24 is cured. When the upper end of the shear reinforcing bar 11 reaches the hole bottom 23a, a wedge (fall prevention means) (not shown) is provided from the opening 23b side so that the shear reinforcing bar 11 does not fall until the grout 24 is hardened. Drive in and temporarily fix. Then, after the grout 24 is cured, the wedge is removed, and as shown in FIG. 5 (4), the opening 23b is closed with the mortar 25 (or grout) to finish the surface.

In this way, when performing shear reinforcement work on the ceiling of the skeleton, a fall prevention means such as a wedge may be arranged in the opening 23b so that the shear reinforcing bar 11 inserted in the drilled hole 23 does not fall. The complicated work of removing is required, and a method that enables easier and smoother construction is desired.

Therefore, as disclosed in Japanese Patent Application Laid-Open No. 2016-183501, a method is proposed in which an anchor fixing means composed of a needle member and a ring member is previously attached to a shear reinforcing reinforcing bar and inserted into the drilling hole. Has been done. According to this method, the shear reinforcing bar can be suitably held in the drilled hole only by inserting the shear reinforcing bar equipped with the anchor fixing means, and as a result, the fall prevention means for the opening of the drilled hole is prevented. There is a possibility that the construction period can be shortened and the cost can be reduced by eliminating the need for both the placement work and the removal work.

Japanese Unexamined Patent Publication No. 2016-183501

However, it is very difficult to attach the anchor fixing means described in Patent Document 1 to the shear reinforcing bar at the construction site. In reality, the anchor fixing means is attached to the shear reinforcing bar in advance at the factory and then attached to the construction site. Since it will be transported to, various problems will arise.

Specifically, in this anchor fixing means, since a closed annular element (ring member) is adopted as a means for attaching the needle member to the outer periphery of the shear reinforcing reinforcing bar, this is attached to the shear reinforcing reinforcing bar. In order to do so, it is necessary to first insert the upper end of the shear reinforcing bar without the nut inside the ring member, and then attach the nut to the upper end of the shear reinforcing bar and tighten it. Since torque control is required when tightening this nut, it is not realistic to perform the mounting work at the construction site.

Therefore, the installation work of the fixing means is performed in advance at the factory, and the installed shear reinforcing bars are transported to the construction site. In this case, the bulk (packing shape) is compared with the case where only the shear reinforcing bars are transported. There is a problem that the transportation cost increases. In addition, if a large number of installed shear reinforcing bars are randomly packed during transportation, the needle members that should protrude radially outward will bend inward during transportation, and the original function (inner wall of drilling) will be achieved. There is a possibility that the function of preventing the product from falling by being caught in the product) will be impaired. For this reason, when transporting the mounted shear reinforcing bars, it is necessary to sufficiently cure each one before packing, which causes a problem that the transport cost is further increased.

The present invention is intended to solve such a problem in the prior art, and the mounting work on the anchor can be easily carried out at the construction site, and the construction period can be shortened without increasing the transportation cost. It is an object of the present invention to provide a clip for fixing an anchor and a method for fixing the anchor, which can realize a reduction in construction cost.

The anchor fixing clip according to the present invention has a leg portion, a pair of sandwiching portions that sandwich the outer peripheral surface of the anchor, and a connecting portion that elastically connects the pair of sandwiching portions, and is between the sandwiching portions. When the outer peripheral surface of the anchor is properly sandwiched and attached to the anchor, the legs project in a direction inclined with respect to the axis of the anchor, and the legs are outward from the connecting portion with reference to the axis of the anchor (of the anchor). It is characterized in that it is configured to protrude (to a position farther from the axis).

It is preferable that the pair of sandwiching portions are configured to face each other at a predetermined interval, and at least one of them has a bulging portion formed so as to bulge outward, and two legs. It is preferable that the portions are configured to face each other at a predetermined interval, and the tip side is configured to expand.

In the method for fixing an anchor according to the present invention, two anchor fixing clips having a size in which the tip of the leg expands larger than the diameter of the hole is formed in opposite directions about the axis of the anchor and on the leg. It is characterized in that it is attached to the anchor so that the tip side is inclined toward one side, and the leg is inserted into the hole in a direction that is inclined toward the outside of the hole from the opening. In this case, it is preferable to bind the leg portion of one anchor fixing clip attached to the anchor and the connecting portion of the other anchor fixing clip with a binding material.

The clip for fixing an anchor according to the present invention has a very simple structure, and can be manufactured extremely easily and at low cost by simply bending a metal wire rod without casting or welding. It can be suitably used when the anchor is to be fixed in the hole, including the case where the anchor is inserted upward into the hole formed upward from the ceiling surface of the skeleton and fixed.

According to the method for fixing an anchor according to the present invention, it is not necessary to arrange or remove a fall prevention means such as a wedge on the opening side, and further, a finishing step (a step of closing the opening of a hole to finish the surface). ) Can be carried out without waiting for the grout in the drilling to harden, and as a result, the problems of shortening the construction period, reducing the construction cost, and increasing the transportation cost can be suitably avoided. ..

FIG. 1 is a view showing an external configuration of an anchor fixing clip 1 according to the first embodiment of the present invention, FIG. 1 (1) is a plan view of the anchor fixing clip 1, and FIG. 1 (2) is a plan view. , It is the side view. FIG. 2 is an explanatory view of an anchor fixing method according to a second embodiment of the present invention, and FIG. 2 (1) shows an upper front surface of a shear reinforcing reinforcing bar 11 to which anchor fixing clips 1, 1'are attached. FIG. 2 (2) is a side view thereof, and FIG. 2 (3) is a horizontal cross-sectional view of the shear reinforcing bar 11 by X-rays shown in FIG. 2 (2). FIG. 3 is an explanatory diagram of an anchor fixing method according to a second embodiment of the present invention. FIG. 4 is a plan view of the anchor fixing clip 1 according to the third embodiment of the present invention. FIG. 5 is a diagram showing a general construction example (construction procedure) of the conventional shear reinforcement work carried out on the ceiling portion of the skeleton.

The present invention can be implemented not only as an "anchor fixing clip" but also as a "method of fixing an anchor" using this clip. Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

First, as the first embodiment of the present invention, an "anchor fixing clip" will be described. FIG. 1 is a diagram showing an external configuration of an anchor fixing clip 1 according to the present invention. As shown in the figure, the clip 1 is a metal wire rod (diameter 1.6 mm) having a basic shape of "U". It is composed of iron wire rods, steel wire rods, etc.), and has two leg portions 2 and 2, a connecting portion 3, and two (paired) holding portions 4 and 4.

The two sandwiching portions 4 and 4 are configured to face each other at a predetermined interval, and in the present embodiment, the central bulging portion 4a formed so as to bulge outward and both sides thereof (FIG. 6). 1 (1) is composed of a neck portion (neck portion 4b on the connecting portion 3 side and neck portion 4c on the leg portion 2 side) formed so as to be constricted inward (upper and lower). .. As shown in FIG. 1, the distance between the left and right bulging portions 4a and 4a is larger than the distance between the left and right neck portions 4b and 4b and the distance between the left and right neck portions 4c and 4c.

The two legs 2 and 2 are also configured to face each other at a predetermined interval, and as shown in FIG. 1 (1), the tip side thereof expands outward in a "C" shape. It is configured. Further, as shown in FIG. 1 (2), when the sandwiching portions 4 and 4 are held horizontally, the tip side thereof is configured to be inclined downward, and therefore, the sandwiching portions 4 and 4 are configured to be inclined downward. When the outer peripheral surface of the anchor is properly sandwiched between them and attached to the anchor, the legs 2 and 2 project in a direction inclined with respect to the axis of the anchor.

As shown in the drawing, the connecting portion 3 elastically connects the holding portions 4 and 4, and is formed in a "U" shape in the present embodiment, but has a "C" shape. It may have a curved shape.

As described above, the anchor fixing clip 1 according to the present embodiment has a very simple structure, and it is extremely easy to perform by simply bending a metal wire rod as a raw material (without casting, welding, etc.). Moreover, it can be manufactured at low cost. Then, as will be described later, an attempt is made to fix the anchor in the drilled hole, including a case where an anchor (shear reinforcing reinforcing bar, etc.) is inserted upward into the drilled hole formed upward from the ceiling surface of the skeleton and fixed. When doing so, it can be preferably used.

Next, as a second embodiment of the present invention, an "anchor fixing method" (an example of application to shear reinforcement work for a ceiling portion of an existing concrete structure) will be described. FIG. 2 is an explanatory diagram of the “anchor fixing method” according to the present invention. As shown in FIGS. 2 (1) and 2 (2), first, two clips 1, 1 ′ are attached to an anchor (in the present embodiment). In the opposite direction (180 ° different from the axis of the shear reinforcing bar 11) with respect to the upper part of the "shear reinforcing bar 11"), and the tip side of the legs 2 and 2'inclins downward. Install in the orientation (in the direction of projecting in the direction inclined with respect to the axis of the shear reinforcing bar 11).

More specifically, it is assumed that the upper portion of the shear reinforcing reinforcing bar 11 is sandwiched between the sandwiching portions 4 and 4 of the clip 1 and between the sandwiching portions 4'and 4'of the clip 1'. Further, the sandwiching portions 4 and 4 of the clip 1 and the sandwiching portions 4'and 4'of the clip 1'are overlapped vertically, and further, the clip 1 which is the upper side of the two clips 1 and 1' However, it is assumed that the shear reinforcing bar 11 is caught on the lower side of any of the ribs 11a (see FIGS. 2 (1) and 2 (2)).

Then, as shown in FIG. 2 (3), the legs 2 and 2'of the clips 1 and 1'protrude radially from the shear reinforcing bar 11 toward the outside, and the axis of the shear reinforcing bar 11 is aligned. As a reference, it is in a state of protruding outward from the connecting portion 3 (to a position farther from the axis of the shear reinforcing reinforcing bar 11). As described above, the two holding portions 4 and 4 of the clip 1 (and the two holding portions 4'and 4'of the clip 1') are configured to face each other at a predetermined interval and are at the center. Since it is composed of the bulging portion 4a and the two neck portions 4b and 4c on both sides thereof, the outer peripheral surface of the shear reinforcing reinforcing bar 11 can be stably sandwiched by the four contact points.

After the clips 1 and 1'are attached to the shear reinforcing reinforcing bar 11, as shown in FIG. 2 (3), the legs 2 and 2 of the clip 1 and the connecting portion 3'of the clip 1'are connected to the binding material 12 (wire or the like). ) To bind and bind, and similarly, on the opposite side, the connecting portion 3 of the clip 1 and the legs 2'and 2'of the clip 1'are bound and bound with the binding material 12, and the shear reinforcing reinforcing bar is used. Clips 1 and 1'are not easily dropped from 11.

Next, as shown in FIG. 3 (1), the shear reinforcing bar 11 to which the clips 1 and 1'are attached is opened in the hole 23 formed upward from the ceiling surface 22 of the skeleton 21. Insert upward from 23b. When inserting the shear reinforcing reinforcing bar 11, the inner wall of the drilled hole 23 is preliminarily roughened, and the grout 24 is injected into the inside of the drilled hole 23 in advance.

As described above, the clips 1 and 1'are in a state in which the legs 2 and 2'protrude radially outward, and the tips of the legs 2 and 2'are larger than the diameter of the drilled hole 23. Since the clips 1, 1'of the size to be opened are used, when the shear reinforcing reinforcing bar 11 is to be inserted into the drilled hole 23 from the opening 23b, as shown in FIG. The legs 2, 2'will interfere with each other, but since the tips of the legs 2, 2'are inclined downward (that is, the legs 2, 2'are cut from the opening 23b. (Because it is inserted so as to incline toward the outside of the hole 23), if the shear reinforcing reinforcing bar 11 is pushed further upward from that state, the legs 2 and 2'will be narrowed by the opening 23b. It can be inserted without any problem.

When the shear reinforcing bar 11 is pushed further upward from the time when the entire clips 1 and 1'enter the drilling 23, the upper end of the shear reinforcing bar 11 is formed in the drilling 23 as shown in FIG. 3 (2). Until the hole bottom 23a (the innermost part of the hole 23) is reached, the legs 2 and 2'constricted by the hole 23 are in a state of being stretched outward by the restoring force, and the hole 23 is formed. The inner wall of the hole 23 (a large number of irregularities such as grooves are formed by the roughening treatment) is scratched to enter the hole 23.

However, when a force in the opposite direction (downward) is applied to the shear reinforcing reinforcing bar 11, the tips of the legs 2 and 2'are caught by the unevenness of the inner wall of the drilling 23 and become immobile. The shear reinforcing bar 11 once inserted is in a state where it does not fall from the drilled hole 23 even when a downward force is applied by gravity.

In the conventional shear reinforcement work (see FIG. 5), a wedge is driven from the opening 23b side to temporarily fix the grout 24 so that the shear reinforcement 11 does not fall from the drilled hole 23 until the grout 24 is hardened. After the grout 24 was hardened, the wedge was removed, and then the final step (the step of closing the opening 23b with the mortar 25 (or grout) to finish the surface) was performed. According to this, it is not necessary to dispose or remove the fall prevention means such as a wedge on the opening 23b side, and further, the finishing step is performed before the grout 24 is cured (that is, without waiting for the grout 24 to be cured). ) It can be carried out, so that the construction period can be shortened and the construction cost can be reduced.

Further, when the shear reinforcing reinforcing bar 11 to which the clips 1 and 1'are attached is inserted into the drilling hole 23, the legs 2 and 2'protruding radially are in a state of being stretched against the inner wall of the drilling hole 23. The shear reinforcing bar 11 can be held at the center position in the drilled hole 23. Further, since the clips 1 and 1'can be easily attached at the construction site, the problem of an increase in transportation cost can be suitably avoided.

In FIGS. 2 and 3, for convenience of explanation, the clips 1 and 1'are attached at positions close to the upper leg portion of the shear reinforcing reinforcing bar 11, but the diameter of the shear reinforcing reinforcing bar 11 is increased from the upper leg portion. It is preferable to mount it at a position where a dimension (± 20%) corresponding to 5 times the (nominal diameter) is placed.

Further, in the present embodiment, as one specific example of the anchor fixing method according to the present invention, an example of application to shear reinforcement work for the ceiling portion of an existing concrete structure (from the ceiling surface upward). A case where a shear reinforcing bar or the like is inserted upward and fixed in the formed hole) has been described, but the method according to the present invention is in the hole formed downward from the floor surface of the skeleton or in the skeleton. It can also be suitably used when a shear reinforcing bar or other anchor is inserted and fixed in a hole formed laterally from the wall surface.

Further, in the present embodiment, as described above, clips 1, 1'that can stably sandwich the outer peripheral surface of the shear reinforcing reinforcing bar 11 by four contacts are used, but as shown in FIG. 4, two sandwiching portions are used. Of 4 and 4, a clip 1 (third embodiment of the present invention) in which a bulging portion 4a is formed only in one of the sandwiching portions 4 and the shear reinforcing reinforcing bar 11 is sandwiched by three contacts may be adopted. it can.

1,1': Anchor fixing clip,
2, 2': Legs,
3,3': Connecting part,
4, 4': Holding part,
4a: bulge,
4b, 4c: neck part,
11: Shear reinforcement rebar,
11a: rib,
12: Bundling material,
21: Skeleton,
22: Ceiling surface,
23: Drilling,
23a: Hole bottom,
23b: Opening,
24: Grout,
25: Mortar,

Claims (3)

A pair of legs that are configured to face each other at a predetermined interval and are configured so that the tip side expands, and a pair of sandwiches that are configured to face each other at a predetermined interval and sandwich the outer peripheral surface of the anchor. It has a portion and a connecting portion that elastically connects the pair of sandwiching portions.
The two sandwiching portions are a central bulging portion formed so as to bulge outward, a neck portion on the connecting portion side formed so as to be constricted inward on both sides thereof, and a neck on the leg side. Each has a part
The connecting portion is configured to project in the extension direction of the holding portion.
When the outer peripheral surface of the anchor is properly sandwiched between the sandwiched portions and attached to the anchor, the legs project in a direction inclined with respect to the axis of the anchor and are more than the connecting portion with reference to the axis of the anchor. Anchor fixing clip characterized by being configured to project outward. A method of fixing an anchor in a hole by using the anchor fixing clip according to claim 1.
Two anchor fixing clips with a size in which the tip of the leg expands larger than the diameter of the drilled hole so that they are oriented in opposite directions with respect to the axis of the anchor and the tip side of the leg is inclined toward one side. Attach it to the anchor in the correct orientation,
A method for fixing an anchor, wherein the leg is inserted into the drilling hole in a direction in which the leg portion is inclined toward the outside of the drilling hole. The leg of one anchor fixing clip attached to the anchor and the connecting part of the other anchor fixing clip are attached to the neck part of one anchor fixing clip on the leg side and the other anchor fixing clip. The method for fixing an anchor according to claim 2 , wherein the anchor is tied and bound with a binding material at a position of a neck portion on the connecting portion side.

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