JP2003232034A - Spacer for cage - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perfectly eliminate the mounting of a spacer on a cage by welding, enable the easy mounting of the spacer at any place in the cage, and allow sure prevention of deformation of a spacer protrusion, in the spacer for securing a thickness of cover concrete for a main reinforcement of the cage for a construction method for a cast-in- place pile and the like. <P>SOLUTION: This spacer 10 for being mounted on an outer side surface of the cage 1 comprises: the protrusion 11 which has an approximate U shape, etc., and protrudes outward in a direction perpendicular to the main reinforcement 2 along the axial direction of the main reinforcement 2; a locking part 12 which is integrally provided in an upper part of the protrusion 11, and composed of a pair of hook pieces 12b locked to a hoop 3 in such a manner as to sandwich the main reinforcement 2 in between; a fitting part 14 which is integrally provided in a lower part of the protrusion 11 and has a fitting groove 13 which is fitted into the main reinforcement 2 from a lateral direction; and a coupling member 15 for coupling both ends of the protrusion 11. A hook piece 12a is locked to the hoop 3; the fitting groove 13 is fitted into the main reinforcement 2 by pressing in the fitting part 14; the spacer 10 is easily fixed to a main reinforcement position of the cage 1 without the use of the welding; and the deformation of the protrusion 11 is prevented by the coupling member 15. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rebar 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, an earth drill method, after constructing a surface casing having a diameter larger than the designed pile diameter, the support layer is excavated, and after the excavation is completed, a rebar cage is incorporated. A spacer is provided on the outer side surface of the reinforcing bar cage in order to secure the concrete covering thickness (for example, about 10 to 15 cm) of the main reinforcing bar.

FIG. 3 shows an example of a conventional spacer 50. A straight plate material is formed and processed, and a convex portion having a substantially U-shape or a circular arc shape in a side view protruding toward the outside of the rebar cage at an intermediate portion. The upper and lower flat plate portions 52 are formed by forming the portion 51 and the flat plate portions 52 that are integrated at the upper and lower ends.
It is fixed by welding 53.

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

[0005]

In recent years, in assembling a rebar cage, it has been desired to eliminate welding which may cause a decrease in strength due to welding defects and the like, and the spacer is also attached to the main bar or the hoop bar by welding. Need to avoid. In the above-described conventional spacer 50 of FIG. 3, since it is fixed to the main bar 2 by welding 53, a spacer that is not attached to the main bar or the hoop bar by welding has been demanded.

FIG. 4 shows an example of this, and this spacer 6
0 is a convex portion 6 that is substantially U-shaped or arc-shaped in side view similar to FIG.
A hook portion 62 that is hooked from above to the hoop muscle 3 to be attached is integrally provided at the upper end portion of the first hose 1, and the flat plate portion 63 at the lower end portion of the convex portion 61 is welded to the outer surface of the reinforcing ring (flat bar) 4.
It is fixed at 4.

In the case of this spacer 60, since the reinforcing ring 4 is not a strength member, there is no problem in welding, but
It can be attached only where the reinforcing ring 4 is,
Problems such as the inability to place spacers at arbitrary positions, time and cost for installation due to welding work, and displacement due to large force due to installation on hoop reinforcement 3 and reinforcing ring 4 There is.

The present invention has been made in order to solve the above-mentioned conventional problems, and an object thereof is to completely eliminate welding attachment to a rebar cage and to place it anywhere in the rebar cage. Another object of the present invention is to provide a spacer for a reinforcing rod cage that can be easily attached and that can reliably prevent deformation of the spacer protrusion.

[0009]

According to a first aspect of the present invention, there is provided a spacer which is attached to an outer surface of a reinforcing bar cage, and which is a main bar of a convex portion projecting toward the outside of the reinforcing bar basket along the axial direction of the main bar of the reinforcing bar cage. A locking portion that is attached to the hoop muscle of the reinforcing bar cage at the main bar position is provided at one end in the axial direction, and a fitting groove that is fitted to the main bar from the direction perpendicular to the main bar at the other end in the axial direction of the main bar of the convex portion. Reinforcing bar, characterized in that a fitting portion having a ridge is provided, and a portion on the locking portion side of the convex portion and a portion on the fitting portion side are connected by a connecting member or an oblique connecting member along the main bar axial direction. It is a cage spacer (see FIGS. 1 and 2).

In the present invention, the material of the spacer may be hard plastic or metal.
The connecting member has a plate shape or a rod shape, and for example, both ends of the connecting member along the axial direction of the main bar are integrally connected to the joint portion of the convex portion and the locking portion and the joint portion of the convex portion and the fitting portion, respectively. (See Figure 2 (a)). The connecting position is not limited to this, and may be any portion at both ends of the convex portion, and the end portion of the convex portion and the corner portion are connected by an oblique connecting member (one diagonally or two diagonally X-shaped). Alternatively, the middles of the upper and lower sides of the protrusion may be connected to each other by a connecting member along the axial direction of the main bar. Also,
It is preferable that a connecting member is provided on both side surfaces of the convex portion and the pair of left and right connecting members are used for connection.

According to a second aspect of the present invention, in the spacer of the reinforcing bar cage according to the first aspect, the engaging portion has a pair of left and right hook pieces that are hooked on the hoop muscle so as to sandwich the main muscle. It is a spacer of the characteristic rebar cage (Fig. 1,
See FIG. 2).

That is, the engaging portion may have any shape as long as it can be engaged with the hoop muscle at the main muscle position, but it is preferable to use a pair of left and right hook pieces. As shown in FIG. 2 (a), the hook piece preferably has a shape to be hooked from the inside of the rebar cage, but it may be hooked from the outside.

According to a third aspect of the present invention, in the rebar cage spacer according to the first aspect, the fitting portion has a pair of left and right fitting pieces sandwiching the main bar. It is a spacer (see FIGS. 1 and 2).

That is, the fitting groove is formed by a pair of right and left fitting pieces, the fitting portion is pushed into the main bar from the direction perpendicular to the main bar, and the pair of left and right fitting pieces sandwich and fit. The fitting piece may be a plate-like piece, but as shown in FIG. 2, it is preferable that the fitting piece is a tubular fitting part having an arcuate cross section and long in the axial direction of the main muscle.

The spacer may be attached to the rebar cage with the engaging portion on the upper side and the fitting portion on the lower side. Conversely, the spacer may be attached on the lower side with the engaging portion on the upper side. Then, it may be attached.

The spacer having the above-mentioned structure is attached to the outer side surface of the reinforcing bar cage along the main bar before being installed. When installing, hook a pair of hook pieces of the locking part on the hoop muscle so as to sandwich the main bar, lock one end of the spacer to the hoop muscle at the main bar position, and push the fitting part against the main bar. The fitting groove is fitted to the main bar, and the other end of the spacer is fixed to the main bar.

It is possible to completely eliminate the welding attachment to the rebar cage, and to eliminate the decrease in strength due to welding defects and the like. Further, since the spacer can be fixed by simply pushing it in, the spacer can be easily attached in a short time. Moreover, since the spacers are attached to the intersections of the main bars and the hoop bars, which are arranged in a large number in the reinforcing bar cage, the spacers can be attached to arbitrary positions. Further, since it is attached to the position of the main bar, the spacer can be attached firmly. Further, the rigidity of the convex portion is increased by the connecting member that connects both end portions of the convex portion, and the convex portion is not deformed by external force.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described based on an illustrated embodiment. This embodiment is an example in which the present invention is applied to a reinforcing bar cage of a cast-in-place pile by an earth drill method using a surface layer casing. 1 and 2 show an example of the case where the spacer of the reinforcing bar cage of the present invention is made of plastic.

As shown in FIG. 1, a reinforcing bar cage 1 used for a cast-in-place pile is composed of a number of main bars 2 arranged in parallel at intervals in the circumferential direction, and an axis outside the main bars 2. Direction and a reinforcing ring 4 (see FIG. 4) arranged inside the main bar 2 at a pitch larger than the mounting pitch of the hoop bar 3 inside the main bar 2 without welding. In this case, the main bar 2 and the hoop bar 3 are fixed with a binding wire or a binding metal fitting, and the main bar 2 and the reinforcing ring 4 are fixed with a holding metal fitting or the like.

As shown in FIGS. 1 and 2, the spacer 10 attached to the outer surface of the rebar cage 1 is shaped like a U-shape or a circle that protrudes outward along the axis of the main bar and at right angles to the main bar. The arc-shaped convex portion 11, the locking portion 12 that is integrally provided on the upper portion of the convex portion 11 and is attached to the hoop muscle 3 from below in the axial direction of the main muscle at the main muscle position, and integrally on the lower portion of the convex portion 11. The engaging portion 14 is provided with a fitting portion 14 having a fitting groove 13 that fits into the main bar 2 in a direction perpendicular to the main bar, and a connecting member 15 that connects the locking section 12 and the fitting section 14.
The fitting portion 14 makes it possible to easily fix it along the main bar 2, and the connecting member 15 prevents the convex portion 11 from being deformed by an external force.

The engaging portion 12 is a flat plate portion 1 which integrally protrudes upward from the upper end portion of the convex portion 11 substantially parallel to the main bar 2.
2a and hooks 12b, 12b that are integrally projected from the flat plate portion 12a in a pair on the left and right sides and are curved outward (to the side of the anti-main muscles) and have a circular side view.

The hook pieces 12b, 12b are formed so that their facing intervals are slightly larger than the diameter of the main bar 2 and are inserted inward and upward from below the hoop muscle 3, so that the hook piece 12 can be caught on the hoop muscle 3 with the main bar 2 interposed therebetween. You can Since the center portion of the inner surface of the flat plate portion 12a hits the main bar 2 in the hooked state, it is prevented from moving inward by an external force. The side shape of the hook piece 12b is an arc having an inner diameter substantially equal to the outer diameter of the hoop muscle 3 and a central angle of 180 ° or more, and is fitted to the hoop muscle 3 so as not to come off. In addition, a folding piece 12c is provided at the tip of the hook piece 12b so that the hook piece 12b can be easily fitted to the hoop muscle 3.

The fitting portion 14 is a flat plate portion 1 which integrally projects from a lower end portion of the convex portion 11 and which extends downward substantially parallel to the main bar 2.
4a and a pair of left and right fitting pieces 14b, 1 that are integrally provided inside the flat plate portion 14a (on the side of the main bar) and sandwich the main bar 2 therebetween.
4b, and the fitting groove 13 is formed by the pair of left and right fitting pieces 14b, 14b.

The fitting piece 14b is a member that is long in the axial direction of the main bar 2 and has a circular arc with an inner diameter substantially equal to the outer diameter of the main bar 2 so as to form a pair of circular fitting grooves 13 in plan view. ,
It is fitted to the main bar 2 in a state of being sandwiched by a pair of cylindrical fitting pieces 14b, 14b so as not to come off by an external force.
In addition, the main bar 2 is usually a deformed steel bar with unevenness, and a locking projection 14c is formed along the axial direction of the main bar 2 on the tip end side (rebar cage side) of the inner surface of the fitting piece 14b. Two
I'm trying not to come off. Further, a folding piece 14d is provided at the tip of the fitting piece 14b so that the fitting piece 14b can be easily fitted to the main bar 2.

The connecting member 15 is parallel to the main shaft 2 and has a convex portion 11.
Is a plate-like member having a width in the uneven direction, and the upper and lower ends thereof are the connection corners of the convex portion 11 and the locking portion 12, and the convex portion 1
1 and the fitting portion 14 are integrally attached to the connection corner portions, and are also disposed on both left and right side surfaces of the convex portion 11. Therefore, the upper part and the lower part of the convex portion 11 are connected and reinforced by the pair of left and right connecting members 15, so that the convex portion 11 can be prevented from being deformed in the direction in which the engaging portion 12 and the fitting portion 14 are separated from each other. .

The spacer 10 of this embodiment is made of hard plastic and has a convex portion 11, a locking portion 12, a fitting portion 14,
The connecting member 15 is integrally molded. Since it is made of plastic, reinforcing ribs 11a are provided on both side surfaces of the concave portion 11, and vertical and horizontal reinforcing ribs (not shown) are provided on the inner surface (the surface on the main bar side).

The spacer 10 having the above-described structure is attached to the outer surface of the assembled rebar cage 1. In the circumferential direction of the rebar cage 1, the main bars 2 are arranged at appropriate intervals in the circumferential direction, and in the longitudinal direction of the rebar cage 1, the hoop bars 3 are arranged at appropriate intervals. To do. At the time of attachment, the hook pieces 12b, 12b are hooked on the hoop muscle 3 so as to sandwich the main muscle 2, and the pair of left and right fitting pieces 14b, 14 are attached.
The spacer 10 can be easily fixed to the main bar 2 only by pushing b into the main bar 2.

After the excavation is completed, such a reinforcing bar 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 rebar cage 1 is provided with the excavation hole A.
Set at the center of. Further, when the casing is pulled out after the concrete is poured, the unevenness of the reinforcing bar cage 1 is prevented by the positioning action of the convex portion 11 of the spacer 10. Convex part 1
Since 1 is reinforced by the pair of left and right connecting members 15 and 15, it does not deform and can reliably perform the function of the spacer.

In this embodiment, the spacer made of plastic is exemplified, but the spacer is not limited to this and may be made of metal. The locking portion 12 exemplifies a hook piece that is hooked from the inside, but is not limited to this, and a hook piece that is hooked from the outside may be used. It is also possible to use a one-piece method such as inserting into. The fitting portion 14 includes a pair of fitting pieces 14b, 14
Although a cylindrical shape made of b is illustrated, the shape is not limited to this, and a plate shape or the like may be used.

The connecting member 15 may be the upper and lower oblique side portions of the convex portion 11 as shown by the chain double-dashed line in FIG.
The ends of the protrusions 11 and the corners may be connected by diagonal connecting members 15 (one diagonally or two diagonally X-shaped), or the middle of the upper and lower hypotenuses of the convexes 11 may be the main line. You may connect with the connecting member 15 along an axial direction of.

Further, in the illustrated example, the locking portion 12 is mounted upward, but the invention is not limited to this, and the locking portion 12 may be mounted downward.

In the above, the example applied to the steel reinforcement cage of the cast-in-place pile method was described, but the present invention is not limited to this, and the spacer of the present invention can also be applied to underground continuous walls and other steel reinforcement cages. .

[0033]

[Effects of the Invention] (1) A locking portion is provided at one end of the convex portion of the spacer, and a fitting portion is provided at the other end, and the locking portion is attached to the hoop muscle at the main reinforcement position. Since it is fitted to the main bar by pushing it against, the welding attachment to the rebar cage can be completely eliminated, strength reduction due to welding defects, etc. can be eliminated, and sound cast-in-place piles without strength reduction Can be created.

(2) Since the time-consuming and costly welding work can be eliminated, and the spacer can be fixed by pushing the end portion of the spacer, the spacer can be easily attached in a short time. The cost can be reduced.

(3) Since it is attached to the intersection of the main bar and the hoop bar, which are arranged in a large number in the rebar cage, the spacer can be mounted at any place.

(4) Since it is attached to the position of the main bar, the spacer can be firmly attached, and even if a large force is applied,
There is no fear that the spacer will be displaced, and the intended purpose as a spacer can be achieved.

(5) The connecting member for connecting both ends of the convex portion increases the rigidity of the convex portion, and the convex portion is not deformed by an external force, so that the function of the spacer can be surely fulfilled.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a spacer of a reinforcing bar cage of the present invention.

2 is a spacer of FIG. 1, (a) is a side view, (b) is a rear view, and (c) is a sectional view taken along line cc.

FIG. 3 is a side view showing a spacer of a conventional reinforcing bar cage.

FIG. 4 is a perspective view showing another spacer of the conventional reinforcing bar cage.

[Explanation of symbols]

A ... Drilling hole 1 ... Rebar cage 2 ... Main story 3 ... Hoop muscle 4 ... Reinforcement ring 10 ... Spacer 11 ... convex part 12 ... Locking part 12a ... Flat plate part 12b ... Hook piece 12c ... folded piece 13 ... Mating groove 14 ... Fitting part 14a ... Flat plate part 14b ... Mating piece 14c ... ridge 14d ... folded piece 15 ... Connecting member

Claims (3)

[Claims] 1. A hoop bar of a reinforcing bar cage, which is a spacer attached to the outer side surface of the reinforcing bar cage, and which is located at one end in the axial direction of the main bar of the convex portion projecting toward the outside of the reinforcing bar cage along the axial direction of the reinforcing bar cage. And a fitting portion having a fitting groove for fitting the main bar from the direction perpendicular to the main bar is provided at the other end of the convex part in the main bar axial direction. 2. A spacer of a reinforcing bar cage, wherein a portion on the locking portion side and a portion on the fitting portion side of are connected by a connecting member or an oblique connecting member along the main muscle axial direction. 2. The rebar cage spacer according to claim 1, wherein the locking portion has a pair of left and right hook pieces that are hooked on the hoop muscle so as to sandwich the main muscle. Spacer. 3. The reinforced cage spacer according to claim 1, wherein the fitting portion has a pair of right and left fitting pieces sandwiching the main bar.