JP2002302943A - Spacer for cage - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a spacer for securing concrete covering depth of main reinforcement bars of a cage in a cast-in-place pile construction method or the like which completely dispenses with welding to the cage, and which can be easily installed to any position in the cage. SOLUTION: This spacer 10 to be installed on an outer side surface of the cage 1 is composed of a roughly U-shape or arc-shaped protruded part 11 protruded along a main reinforcing bar axis direction toward the outer side perpendicularly to a main reinforcing bar, a lock part 12 comprising a pair of insert pieces 12a integrally provided at an upper part of the protruded part 11 to be inserted from the underside to the inner side of a hoop bar 3 to hold the main reinforcing bar 2, and an engagement part 14 integrally provided with a lower part of the protruded part 11 and having an engagement groove 13 to be engaged with the main reinforcing bar from a lateral direction. The insert piece 12a is inserted inwardly of the hoop bar 3, and the engagement part 14 is caulked, so that the engagement groove 13 is engaged with the main reinforcing bar 2, thereby the spacer 10 can be easily fixed to the position of the main reinforcing bar of the cage 1 without welding at a main reinforcing bar position in the cage.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reinforced cage spacer used for cast-in-place pile construction.

[0002]

2. Description of the Related Art In the case of a cast-in-place pile, for example, in an earth drilling method, a surface casing having a diameter larger than a design pile diameter is built, and then a support layer is excavated. A spacer is provided on the outer surface of the reinforcing bar cage in order to secure a concrete cover thickness (about 10 to 15 cm) of the main reinforcing bar.

FIG. 5 shows an example of a conventional spacer 50, which is formed by forming a linear plate material and projecting toward the outside of a reinforcing bar cage at an intermediate portion in a substantially U-shaped or arcuate side view. A convex portion 51 is formed, and an integrated flat plate portion 52 is formed at the upper and lower ends, and the upper and lower flat plate portions 52 are connected to the main reinforcing bars 2 of the reinforcing bar cage 1.
Are fixed by welding 53.

A plurality of the spacers 50 are arranged at intervals in the circumferential direction of the reinforcing cage 1, and are arranged at a pitch of, for example, 3 m in the axial direction of the reinforcing cage 1. It also has the function of setting a steel cage in the center of the cross section of the borehole.

[0005]

In recent years, in assembling a reinforcing bar cage, it has been demanded to eliminate welding which may cause a reduction in strength due to welding defects and the like, and the spacer is also attached to a main bar or a hoop bar by welding. Need to be avoided. In the conventional spacer 50 of FIG. 5 described above, since the main bar 2 is fixed to the main bar 2 by welding 53, a spacer which is not attached to the main bar or the hoop bar by welding has been demanded.

FIG. 6 shows an example of such a structure.
0 is a substantially U-shaped or arc-shaped convex portion 6 in a side view similar to FIG.
A hook portion 62 for hooking and attaching to the hoop streak 3 from above is integrally provided at the upper end of the projection 1, and a flat plate portion 63 at the lower end of the projection 61 is welded to the outer surface of the reinforcing ring (flat bar) 4.
It is fixed at 4.

In the case of the spacer 60, since the reinforcing ring 4 is not a strength member, there is no problem with welding,
It can only be installed where there is a reinforcing ring 4,
There are problems such as the inability to dispose the spacer at any position, the time and cost required for installation due to the welding work, and the possibility of displacement when subjected to a large force due to the attachment to the hoop streak 3 and the reinforcing ring 4. There is.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to completely eliminate the need for welding to a reinforcing bar cage, and at any position of the reinforcing bar cage. It is an object of the present invention to provide a reinforcing rod cage which can be easily installed.

[0009]

A first aspect of the present invention is a spacer attached to the outer surface of a reinforcing rod cage, the main reinforcing rod having a convex portion protruding toward the outside of the reinforcing rod cage along the main reinforcing rod axial direction of the reinforcing rod cage. At one end in the axial direction, a locking portion is provided which is attached to the hoop bar of the reinforcing bar at the main bar position, and at the other end of the convex portion in the main bar axis direction, a fitting groove is fitted to the main bar from the main bar perpendicular direction. And a fitting portion having the following.

According to a second aspect of the present invention, in the spacer for a reinforcing rod cage according to the first aspect, the locking portion has a pair of left and right insertion pieces inserted into the inside of the hoop bar so as to sandwich the main bar. This is a spacer for a reinforcing rod cage (see FIGS. 1 and 2).

According to a third aspect of the present invention, in the reinforcing rod cage according to the first aspect, the locking portion has a pair of left and right hook pieces that are hooked to the hoop muscle so as to sandwich the main muscle. It is a spacer of the rebar basket which is a feature (Fig. 3,
(See FIG. 4).

The width of the fitting groove of the fitting portion is made slightly smaller than the diameter of the main reinforcement, and the fitting groove is fitted to the main reinforcement by tapping.
The fitting groove may be provided with a locking claw for preventing the fitting portion from being detached from the main muscle.

[0013] The spacer may be attached to the reinforcing bar cage with the engaging portion up and the fitting portion down, or conversely, the locking portion may be down and the fitting portion up. Then, it may be attached.

The spacer having the above configuration is attached to the outer side surface of the reinforcing bar cage along the main bar before being built. At the time of installation, insert a pair of insertion pieces of the locking part inside the hoop muscle so as to sandwich the main muscle, or hook a pair of hook pieces on the hoop muscle so as to sandwich the main muscle, and place one end of the spacer at the main muscle position The fitting groove is fitted to the main bar by hitting the fitting portion with a hammer or the like, and the other end of the spacer is fixed to the main bar.

[0015] Welding to the reinforcing bar can be completely eliminated, and a decrease in strength due to welding defects or the like can be eliminated. Further, since the spacer can be fixed only by striking the end of the spacer, the spacer can be easily attached in a short time. Further, since the spacer is attached to the intersection of the main bar and the hoop bar, which are arranged in a large number in the reinforcing bar cage, the spacer can be mounted at an arbitrary position. Further, since the spacer is attached at the position of the main bar, the spacer can be firmly attached.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on one embodiment shown in the drawings. This embodiment is an example in which the present invention is applied to a steel cage of a cast-in-place pile by an earth drill method using a surface casing. FIGS. 1 and 2 show a first embodiment of a spacer for a reinforcing rod cage according to the present invention. FIG. 3 and FIG. 4 show a second embodiment of the spacer of the reinforcing bar cage according to the present invention.

As shown in FIG. 1, a reinforcing cage 1 used for a cast-in-place pile has a plurality of main reinforcing bars 2 arranged in parallel at intervals in a circumferential direction, and a shaft outside the main reinforcing bars 2. And a reinforcing ring 4 (see FIG. 6) arranged at a pitch larger than the mounting pitch of the hoop bars 3 inside the main bar 2 and has no welding. In this case, the main bar 2 and the hoop bar 3 are fixed with a binding wire or a binding bracket, and the main bar 2 and the reinforcing ring 4 are fixed with a holding bracket or the like.

In the first embodiment shown in FIGS. 1 and 2, a spacer 10 attached to the outer surface of
A substantially U-shaped or arc-shaped convex portion 11 protruding outward in the direction perpendicular to the main muscle along the main muscle axis direction, and integrally provided on the upper part of the convex 11, and the hoop muscle 3 is provided at the main muscle position at the main muscle position. The main muscle comprises a locking portion 12 attached from below in the axial direction of the main muscle, and a fitting portion 14 provided integrally with a lower portion of the convex portion 11 and having a fitting groove 13 fitted to the main muscle 2 at right angles to the main muscle. 2 so that it can be easily fixed.

The locking portion 12 is a flat plate portion 1 integrated with the convex portion 11.
2a, and a pair of left and right insertion pieces 12b, 12b integrally projecting from the flat plate portion 12a. The distance between the insertion pieces 12b, 12b is slightly larger than the diameter of the main bar 2, so that the pair of left and right insertion pieces is formed. Piece 12b,
12b can be inserted inside the hoop muscle 3 with the main muscle 2 interposed therebetween.

Further, as shown in FIG.
a is formed so as to be parallel to the main bar 2,
"b" is composed of a tip portion 12b-1 and a bent portion 12b-2. The distal end portion 12b-1 has a linear shape that is slightly inclined inward, so that it can be easily inserted into the hoop muscle 3 from below. The bent portion 12b-2 is largely inclined inward so as to abut the lower part of the hoop muscle 3. Tip 1
2b-1 prevents the locking portion 12 from being detached from the main muscle 2 in the outward direction, and the bent portion 12b-2 prevents the locking portion 12 from slipping upward.

The fitting portion 14 is a flat plate portion 1 integrated with the projection 11.
4a and a pair of left and right fitting pieces 14b, 14b integrally projecting horizontally from the flat plate portion 14a, and a fitting groove 13 is formed by the pair of left and right fitting pieces 14b, 14b.
The flat plate portion 14 a is formed so as to be parallel to the main bar 2.

The inner width (groove width) of the pair of right and left fitting pieces 14b, 14b is slightly smaller than the diameter of the main bar 2, and the lower part of the spacer 10 is hit with a hammer or the like to be fitted to the main bar 2, and fitted. The joint 14 is prevented from coming off the main bar 2. Further, as shown in FIG. 2 (c), an arc-shaped chamfer 15 is formed on the inner side surface at the tip end of the fitting pieces 14b, 14b.
It can be easily attached to the main bar 2. In addition, the fitting groove 13 is not limited to a fixed width, and may have a tapered shape in which the width increases toward the main bar 2.

The main bar 2 is usually made of a deformed steel bar having irregularities on the surface, and the groove width of the fitting groove 13 is set to be slightly smaller than the diameter of the portion without the vertical and horizontal protrusions. Even if the pair of left and right fitting pieces 14b, 14b are located at the horizontal stitching position, they can be driven into a portion without the horizontal sting by being slightly displaced or deformed in the main muscle axis direction.

Further, a cut groove 16 is formed in the flat plate portion 14a so as to be continuous with the fitting groove 13, so that the fitting pieces 14b, 14b having an L-shaped side view and a bifurcated shape can be obtained. By providing the cut groove 16, the fitting pieces 14b, 14b having an L-shape in side view are easily opened and deformed in a direction away from each other, and can be attached to the main bar 2 having various diameters. For example, if the widths of the fitting groove 13 and the cut groove 16 are processed in accordance with the main bar 2 of 25 mm, the same spacer can be used.
It can be attached to 29mm main bar 2. Cut groove 1
As shown in FIG. 2 (b), the shape of No. 6 has a mountain-shaped upper portion and a semi-circular groove at the apex to facilitate opening.

For the spacer 10 as described above, a straight steel plate or the like is used. After processing the central grooves at both ends of the steel plate, the convex portion 11 is formed, and the locking portion 12 and the fitting portion 1 are formed.
4 can be easily obtained by bending.

The spacer 10 configured as described above is attached to the outer surface of the assembled reinforcing cage 1. In the circumferential direction of the rebar cage 1, it is arranged at a plurality of main bars 2 at appropriate intervals, and in the longitudinal direction of the rebar cage 1, at a plurality of hoop bars 3 at an appropriate interval. I do. At the time of attachment, the pair of left and right insertion pieces 12b, 12b
The spacer 10 can be easily fixed to the main bar 2 simply by inserting it into the inside of the hoop bar 3 so as to sandwich it, and hitting the pair of left and right fitting pieces 14b, 14b into the main bar 2.

After the excavation is completed, such a reinforcing rod cage 1 is inserted into the casing and then into the excavation hole. Due to the smooth guiding action of the convex portion 11 of the spacer 10, the reinforcing bar 1
Set at the center of the In addition, when the casing is pulled out after the concrete is cast, the positioning of the convex portion 11 of the spacer 10 prevents the rebar cage 1 from being biased.

In FIGS. 1 and 2, the locking portion 12 is mounted up, but the present invention is not limited to this, and the locking portion 12 may be mounted down. Even when the locking portion 12 is lowered, the fitting pieces 14b, 14b are firmly fitted to the main bar 2 and the vertical movement of the main bar 2 is restrained. Will not come off.

Next, in the second embodiment shown in FIGS. 3 and 4, the spacer 20 is formed as a substantially U-shaped or arc-shaped projection 21 projecting outward along the main muscle axis direction in the direction perpendicular to the main muscle.
A locking portion 22 integrally provided on the upper portion of the convex portion 21 and attached to the hoop muscle 3 from above in the main muscle axial direction at a main muscle position, and a locking portion 22 provided integrally on a lower portion of the convex portion 21 and provided on the main muscle 2. It is composed of a fitting portion 24 having a fitting groove 23 fitted from a direction perpendicular to the main bar, so that it can be easily fixed along the main bar 2.

The locking portion 22 is composed of a pair of left and right hook pieces 22a, 22a which protrude integrally from the upper part of the projection 21 and are curved downward.
Is formed to be slightly larger than the diameter of the main bar 2 so that the pair of left and right hook pieces 22a, 22a can be hooked on the hoop bar 3 with the main bar 2 interposed therebetween.

As shown in FIG. 4 (a), the hook piece 22a has a semicircular portion 22a-1 having an inner diameter slightly larger than the diameter of the hoop streak 3, and hangs down integrally from one end of the semicircular portion. It consists of a hanging part 22a-2, and this hanging part 22a-
By setting the length of the spacer 2 to an appropriate length, the spacer 2
0 is prevented from leaving the main muscle 2 in the outward direction or coming out upward.

The fitting portion 24, like the locking portion 22, is integrally formed of a pair of left and right fitting pieces 24a, 24a protruding upward from the lower part of the convex portion 21 and bent upward. The fitting groove 23 is formed by the mating pieces 24a, 24a.

The main reinforcement 2 of the pair of right and left fitting pieces 24a, 24a
The inner side surface which comes into contact with the surface may be linear or may be provided with a saw blade-shaped engaging claw 25. In any case, the inner width (groove width) of the pair of right and left fitting pieces 24a, 24a is slightly smaller than the diameter of the main bar 2, and the lower portion of the spacer 20 is fitted to the main bar 2 by hitting with a hammer or the like. , So that the fitting portion 24 does not come off the main bar 2. In addition, the fitting groove 23 is not limited to a fixed width, and may have a tapered shape in which the width increases toward the main bar 2.

The main bar 2 is usually made of a deformed steel bar having irregularities on its surface.
5) is a groove width that is slightly smaller than the diameter of the portion without the vertical and horizontal protrusions. Even if the pair of left and right fitting pieces 24a, 24a are located at the horizontal stitching position, they can be hammered into a portion without the horizontal sting by being slightly displaced or deformed in the main muscle axis direction.

As shown in FIG. 4C, a plurality of saw blade-shaped engaging claws 25 are provided on the inner surfaces of the pair of right and left fitting pieces 24a, 24a in the longitudinal direction of the groove (striking direction). The shape of the saw blade in a plan view is a right-angled triangle or the like, and the pair of oblique sides of the opposing saw blade are shaped to spread in the driving direction, so that the main blade 2 can be easily hit with a relatively small force, and After fixation, the main muscle 2 should not be easily detached.

As the spacer 20 as described above, a straight steel plate or the like is used. After forming a central groove at both ends of the steel plate, a convex portion 21 is formed, and a pair of left and right hook pieces 2 are formed.
It can be easily obtained by bending the 2a, 22a and the fitting pieces 24a, 24a.

The spacer 20 having the above-described structure is attached to the outer surface of the assembled reinforcing cage 1. In the circumferential direction of the rebar cage 1, it is arranged at a plurality of main bars 2 at appropriate intervals, and in the longitudinal direction of the rebar cage 1, at a plurality of hoop bars 3 at an appropriate interval. I do. At the time of attachment, a pair of left and right hook pieces 22a, 22a are hooked on the hoop muscle 3 so as to sandwich the main muscle 2, and a pair of right and left fitting pieces 2 are attached.
4a and 24a are simply slammed into the main bar 2 so that the spacer 10
Can be easily fixed to the main muscle 2.

After the excavation is completed, such a reinforcing rod cage 1 is inserted into the casing and then into the excavation hole. Due to the smooth guiding action of the convex portion 11 of the spacer 20, the reinforcing bar 1
Set at the center of the In addition, when the casing is pulled out after the concrete is cast, the positioning of the convex portion 21 of the spacer 20 prevents the rebar cage 1 from being biased.

Also in the second embodiment, the locking portion 22
Is attached with the upper side, but the present invention is not limited to this.
May be mounted on the bottom. Further, the hook piece 22a is shaped to be hooked from the outside, but may be shaped to be hooked from the inside.

Although the above description has been made of the example in which the present invention is applied to the steel cage of the cast-in-place pile method, the spacer of the present invention is not limited to this, and the spacer of the present invention can be applied to an underground continuous wall and other steel cages. .

[0041]

(1) A locking portion is provided at one end of the convex portion of the spacer, a fitting portion is provided at the other end, the locking portion is attached to the hoop muscle at a main bar position, and the fitting portion is a hammer or the like. To be fitted to the main bar, completely eliminating the welding attachment to the reinforcing bar cage, eliminating the drop in strength due to welding defects, etc., and creating a sound cast-in-place pile with no drop in strength. can do.

(2) Since the time-consuming and costly welding work can be eliminated and the spacer can be fixed simply by striking the end of the spacer, the spacer can be easily and quickly mounted. Cost can be reduced.

(3) The spacer can be attached to any location because it is attached to the intersection of the main bar and the hoop bar, which are arranged in a large number in the reinforcing bar cage.

(4) Since the spacer is attached at the position of the main bar, the spacer can be firmly attached.
There is no risk of the spacer being displaced, and the intended purpose of the spacer can be achieved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a first embodiment of a reinforced cage spacer according to the present invention.

2 (a) is a side view, FIG. 2 (b) is a rear view, and FIG. 2 (c) is a cross-sectional view taken along the line c-c.

FIG. 3 is a perspective view showing a second embodiment of a reinforcing cage basket of the present invention.

4 (a) is a side view, FIG. 4 (b) is a rear view, and FIG. 4 (c) is a cross-sectional view taken along the line c-c.

FIG. 5 is a side view showing a spacer of a conventional reinforcing cage.

FIG. 6 is a perspective view showing another spacer of the conventional reinforcing cage.

[Explanation of symbols]

 A: Excavation hole 1: Reinforcing cage 2: Main bar 3: Hoop bar 4: Reinforcement ring 10: Spacer 11: Convex portion 12: Locking portion 12a: Flat plate portion 12b: Insertion piece 12b-1: Tip portion 12b-2: Fold Curved portion 13 Fitting groove 14 Fitting portion 14a Flat plate portion 14b Fitting piece 15 Chamfer 16 Cut groove 20 Spacer 21 Convex portion 22 Locking portion 22a Hook piece 22a-1 Semicircle Part 22a-2: hanging part 23: fitting groove 24: fitting part 24a: fitting piece 25: locking claw

Claims (3)

[Claims] 1. A hoop bar of a reinforcing rod cage, which is a spacer attached to an outer surface of a reinforcing rod cage, and which is provided at one end in the main reinforcing rod axial direction of a protrusion projecting toward the outside of the reinforcing rod cage along the main reinforcing rod axial direction of the reinforcing rod cage. The main bar is provided with a fitting portion having a fitting groove that is fitted to the main bar from a direction perpendicular to the main bar, at the other end of the convex portion in the main bar axial direction. Reinforced basket spacer. 2. The reinforcing bar cage according to claim 1, wherein the locking portion has a pair of left and right insertion pieces inserted into the inside of the hoop bar so as to sandwich the main bar. Basket spacer. 3. The reinforcing bar cage according to claim 1, wherein the locking portion has a pair of left and right hook pieces hooked on the hoop bar so as to sandwich the main bar. Spacer.